ЛАЗЕРНАЯ СИСТЕМА

Изобретение относится к лазерной технике. Дальномер содержит лазерную систему, содержащую импульсный задающий диодный генератор и по меньшей мере один накачиваемый активный оптоволоконный усилитель мощности, стоящий после упомянутого импульсного задающего диодного генератора. По существу все каналы лазерного света являются оптическими волокнами. Дополнительно система содержит оптическое волокно, один конец которого функционально подключен к выходу упомянутого накачиваемого активного оптоволоконного усилителя, а другой конец функционально подключен к оптике передатчика для излучения лазерного света, зависимого от лазерного света, выводимого из упомянутого активного усилителя. Причем упомянутый другой конец адаптирует диаметр поля моды к упомянутой оптике передатчика, и таким образом определяет расхождение излучаемого лазерного пучка. Технический результат заключается в повышении компактности устройства. 3 н. и 25 з.п. ф-лы, 16 ил.

Halbleiterlaser und Modulationsverfahren

Verfahren zur Erzeugung ultrakurzer optischer Impulse

Laserdioden-Anordnung mit externem Resonator

Laserdioden-Anordnung (10) zur Erzeugung von einmodiger, durchstimmbarer Laserstrahlung (15), mit einer Laserdiode (11), die eine Rückfacette (16) und eine Frontfacette (17) aufweist und einen ersten Resonator (R1) bildet, und mit einem daran angekoppelten externen Resonator (R2), der wenigstens eine optische Transmissionskomponente (30) und wenigstens ein wellenlängenselektives optisches Reflexionselement (40, 50) aufweist und von der Laserdiode (11) emittiertes Laserlicht (13) in den ersten Resonator (R1) zurückkoppelt, dadurch gekennzeichnet, daß die Laserstrahlung (15) über die Rückfacette (16) der Laserdiode (11) auskoppelbar ist, wobei das Verhältnis der Reflektivität der Rückfacette (16) zur Reflektivität des optischen Reflexionselements (40) sehr viel kleiner als 1 ist.

LICHTQUELLE FÜR FASEROPTISCHEN KREISEL MIT WELLENLÄNGENREGELUNG

Optical amplification control apparatus, method for controlling semiconductor optical amplifier, and optical transmission equipment

Optical amplifier

The emission wavelength of the pump laser (5) of an erbium doped fibre amplifier is locked to the peak in the absorption characteristic of its amplifier fibre (4) by means of a feedback loop employing a photodiode (8) to monitor the proportion of the pump power transmitted through the amplifier fibre while the wavelength of the laser is being dithered by means of a tone generator 11. The output of the photodiode 8 is applied to a phase sensitive detector 12. The output of the latter is smoothed by an integrator 13 and is then used to regulate the temperature of the pump laser 5. ...

Temperature compensated optoelectronic device having a laser diode and an electro-absorption modulator

A temperature compensated optoelectronic device 100 has a laser diode 3 and an Electro-absorption Modulator (EAM) device 6 to modulate the output of the laser. A method of forming such a device, which may more particularly be a monolithically integrated optoelectronic component is also disclosed. The optoelectronic device 100 comprises a Distributed Bragg Reflector (DBR) device 4 with an electrically-tuneable input 57 for wavelength-tuning of optical radiation 50 generated by the laser 3. The laser diode 3 has an operating wavelength that varies at a different rate than the band edges of the EAM device 6 as temperature changes. The device employs the DBR device 4 to make compensating changes to the laser wavelength in order to extend the operating temperature range of the optoelectronic device 100 without the need for thermoelectric cooling.

Optimisation of the laser operating point in a laser absorption spectrometer

An operating value of a first laser parameter of a laser device in a laser absorption spectrometer is optimised. The wavelength of laser device emitted light is adjusted by the first or a second laser parameter. The laser absorption spectrometer 100 comprises a lightintensity detector 120 measuring the laser light intensity from the laser device 110. For each of multiple values of the first laser parameter 112: the light intensity detector measures light intensity obtained across a range of second laser parameter values 114, and an extremum in the light intensity measure and a peak position for the extremum are identified. A range of first laser parameter values is identified within the values of the first laser parameter forwhich there is a continuous trend in changes to the identified peak position with changes to the first laser parameter. The first laser parameter operating value is set to be within the identified range. The laser parameters may comprise the laser diode temperature ...

FASHION-COUPLED SOURCE OF DIODE LASER PULSE

PROCEDURE FOR THE WAVELENGTH VOTE OF AN OPTO-ELECTRONIC ELEMENT ARRANGEMENT

Tunable laser

Variable light controlling device and variable light controlling method

Wavelength tunable laser

Optoelectronic component

Laser optics integrated control system and method of operation

Transmitter photonic integrated circuit

DIGITAL OPTICAL NETWORK ARCHITECTURE

A digital optical network (DON) is a new approach to low-cost, more compact optical transmitter modules and optical receiver modules for deployment in optical transport networks (OTNs). One important aspect of a digital optical network is the incorporation in these modules of transmitter photonic integrated circuit (TxPIC) chips and receiver photonic integrated circuit (TxPIC) chips in lieu of discrete modulated sources and detector sources with discrete multiplexers or demultiplexers.

ELECTRICALLY PUMPED VERTICAL CAVITY LASER

Disclosed is an electrically pumped vertical cavity laser structure operating in the mid-infrared region, which has demonstrated room-temperature continuous wave operation. This structure uses an interband cascade gain region, two distributed mirrors, and a low-loss refractive index waveguide. A preferred embodiment includes at least one wafer bonded GaAs-based mirror.

SEMICONDUCTOR LASER DEVICE

External resonator-type lasers as configurations for narrowing the spectral line widths of semiconductor lasers to approximately 10 kHz suffer from the problem that a large number of components are required and need to be assembled with high accuracy, and thus, control circuits become complicated. Wavelength variable lasers based on DFB lasers have also been known, but even wavelength variable lasers based on DFB lasers have limits in narrowing of spectrum line widths because it is difficult to uniformly form long resonators due to production variation. The semiconductor laser device according to the present invention has a semiconductor laser that oscillates in a single mode and has a low-loss optical wave circuit using quartz glass arranged on a common substrate. The optical wave circuit is configured such that a part of light outputted from the semiconductor laser propagates a certain length of an optical path, is reflected by a reflector, and returns to the semiconductor laser. Alternatively ...

SYSTEM AND METHOD FOR CONTROLLING COLLOCATED MULTIPLE WAVELENGTH TUNED LASERS

Systems and methods are disclosed herein for controlling laser beams for a plurality of collocated laser assemblies. The laser beams are optimized by controlling outputs of a primary power source (current for generating a laser beam) and a secondary power source (heating device) for each of the respective laser assemblies. The states of the power supply may be cycled and modulated to provide optimal performance.

PHASE CONTROL BY ACTIVE THERMAL ADJUSTMENTS IN AN EXTERNAL CAVITY LASER

The present invention relates to a wavelength tuneable external-cavity laser module, the laser being tuneable across a predetermined wavelength range and comprising: a thermally stabilised substrate; a gain medium for emitting an optical beam passing through the external cavity along an optical axis, said gain medium being placed in thermal contact with the thermally stabilised substrate; an end mirror for receiving and reflecting the optical beam within the external cavity, and a phase element for controlling the phase of the optical beam and being positioned within the external cavity between the gain medium and the end mirror, wherein said phase element comprises a material having a refractive index that varies in response to changes in temperature and has a transmissivity substantially independent of wavelength across said predetermined wavelength range. The thermally-controllable phase element in the laser external cavity is configured so as to induce a phase variation that compensates ...

Method for the Generation of Ultra-Short Optical Pulses

TUNABLE EXTERNAL CAVITY DIODE LASER

An external cavity laser system composed of a semiconductor diode laser (10), a temperature control (30) and injection current control (40) means the diode laser, an external cavity (60) with a wavelength selector and means for controlling the laser temperature (20), laser injection current and the wavelength selector (110) to obtain arbitrary frequencies within the tuning range of the laser.

PRODUCING LASER LIGHT OF DIFFERENT WAVELENGTHS

In a tunable laser device a plurality of basically identical lasers (3, 3') are arranged adjacent to each other in a line or row on a common substrate (1). The lasers (3, 3') can be DFB-type and they have different emission wavelengths, obtained from e.g. different pitches of gratings (5) which define the wavelengths of the respective lasers. The lasers can be activated to emit light independently of each other by supplying electrical current to contacts (11) located on the top sides of the lasers. When a laser is activated, the other lasers are biased, so that lasers located at one side of the active laser will be transparent to the emitted light, which can then travel from the lasers through an electrooptic modulator (17), and the lasers located at the other side will absorb the light. By controlling the temperature, the wavelength of emitted light can be finely adjusted. Such a laser device has a compact structure, is fairly insensitive to variations of the used drive currents and can ...

Wdm laser wavelength control

Semiconductor light emitting element and variable wavelength laser light source

The present invention provides a semiconductor light emitting element that can obtain oscillation at desired wavelengths. The semiconductor light emitting element comprises a semiconductor substrate 11, an active layer 12 for emitting and propagating light, which is formed in a stripe shape above the semiconductor substrate 11, buried layers 13a, 13b formed on both lateral sides of the active layer 12, a cladding layer 16 formed above the active layer 12 and the buried layers 13a, 13b, a first electrode 17a formed above the cladding layer 16, and a second electrode 17b formed below the semiconductor substrate 11. The active layer 12 opens on one end facet 14a among the two end facets formed by cleavage so that the active layer 12 makes a predetermined angle to the normal direction of the one end facet 14a. A partially heating means 15 for heating a predetermined length portion of the active layer 12 along the direction of light propagation is formed on a first electrode at a position thermally ...

Method for tuning semiconductor laser

A method for controlling a semiconductor laser, which has a plurality of wavelength selection regions respectively having cyclic wavelength characteristics, includes: a step of controlling the refractive indexes of the wavelength selection regions; a step of confirming that the wavelength characteristics achieved by the refractive index control in each wavelength selection region change by one cycle or more compared with the wavelength characteristics achieved with a predetermined value of the refractive index in a state where the refractive index is not controlled; and a step of shifting the confirmed refractive index of the wavelength selection region by the unit of one cycle to the predetermined value.

METHOD AND MEANS FOR CONTROLLING THE FREQUENCY AND POWER OUTPUT OF A TUNABLE LASER DIODE.

Tunable laser

SEMICONDUCTOR OPTICAL ELEMENT, INTEGRATED SEMICONDUCTOR OPTICAL ELEMENT AND SEMICONDUCTOR OPTICAL ELEMENT MODULE

This semiconductor optical element is provided with an optical waveguide formed on a semiconductor substrate. The optical waveguide is provided with: a single mode waveguide section for guiding inputted light in a single mode; a bent section positioned in the latter part of the single mode waveguide section with respect to the waveguide direction of the light; and a flared section that is positioned in the latter part of the bent section with respect to the waveguide direction, is formed in such a manner that the waveguide width widens in the waveguide direction, guides the light in a single mode on the side on which the light is incident, and has a waveguide width that enables the light to be guided in multiple modes on the side on which the light exits.

INTEGRATED MONITORING AND FEEDBACK DESIGNS FOR EXTERNAL CAVITY TUNABLE LASERS

An integrated structure includes front and rear facets (201, 203) optically- coupled by a waveguide (220) passing through the integrated structure. The integrated structure includes a gain section (202) and a reflector (208) optically coupled to the gain section by the waveguide, the reflector to emit an optical output. A modulator (214) is optically coupled to the reflector by the waveguide, the modulator to modulate the optical output. And a control section (216) disposed along the waveguide.

METHODS OF DRIVING LASER DIODES, OPTICAL WAVELENGTH SWEEPING APPARATUS, AND OPTICAL MEASUREMENT SYSTEMS

An optical wavelength sweeping apparatus having a laser diode (100) with an active region (102), and a coupled pulse generator is disclosed. The pulse generator is configured and operable to provide current drive pulses of relatively short duration and high amplitude to the laser diode to selectively and rapidly heat the active region and the immediate vicinity and produce a rapid wavelength sweep of emitted optical radiation. Methods of driving a laser diode, and measurement systems are disclosed, as are other aspects. Even a standard telecommunication DFB laser diode may be used and upon pumping with an electrical current pulse with sub-microsecond duration and amplitude on the order of ampere, a wavelength sweep results from transient heating of the active region with subsequent cooling, determining the duty cycle.

METHOF FOR STABILIZING OPTICAL OUTPUT POWER OF FIBER LASER

A high power fiber laser system is configured with a pump including at least one laser diode module which radiates a pump light coupled into a gain medium of active fiber as a temperature rises from a relatively low temperature to a relatively high temperature. The pump operates at a uniform diode current and configured so that while a pump output power decreases within the predetermined temperature range, absorption of the pump light in the gain medium increases so that the output of the fiber laser system remains substantially uniform.

APPARATUS AND METHODS FOR OPTICAL AMPLIFICATION IN SEMICONDUCTORS

Methods and corresponding apparatus for optical amplification in semiconductors, particularly indirect band-gap semiconductors, and most particularly in silicon. A first aspect of the invention employs certain doping elements to provide inter-band-gap energy levels in combination with optical or current-injection pumping- The doping element, preferably a noble metal and most preferably Gold, is chosen to provide an energy level which enables an energy transition corresponding to a photon of wavelength equal to the signal wavelength to be amplified. The energy transition may be finely “adjusted” by use of standard doping techniques (such as n-type or p-type doping) to alter the conduction and valence band energy levels and thereby also the magnitude of the energy transition. A second aspect of the invention relates to the use of a non-homogeneous heat distribution which has been found to lead to optical amplification effects.

CHANNEL-SWITCHED TUNABLE LASER FOR DWDM COMMUNICATIONS

Source laser (100) qui comprend des matières (122, 124) à dépendance négative de l'indice de réfraction par rapport à la température et à coïncidence indépendante de la température entre les modes de la cavité, et une série de fréquences spécifiées telles que des voies à multiplexage en longueur d'onde dense dans des applications de télécommunications. La gamme spectrale libre peut être réglée pour être égale à une fraction rationnelle de l'intervalle des fréquences spécifiées. La fréquence de fonctionnement peut être définie par un élément de rétroaction (130, 132) à sélectivité de fréquence qui est accordé de manière thermo-optique par application de chaleur provenant d'un actionneur sans accordage substantiel des modes de la cavité. La fréquence de fonctionnement peut être induite de manière à effectuer des sauts numériques entre les fréquences spécifiées. Dans un mode de réalisation particulier, un amplificateur (110) à semi-conducteur et des segments (122, 124) de guide d'ondes polymère ...

OPTICAL TRANSMITTERS

External cavity optical transmitters are disclosed which include a gain chip and a mirror that define an optical cavity. The transmitters further include a modulator operated at or near the same temperature as the gain chip. In some examples, the optical transmitters are temperature controlled to optimize the efficiency and wavelength stability thereof, while maintaining acceptable chirp performance of the modulator. In some examples, the optical transmitters include an electro-optic module disposed within the optical cavity to change the path length thereof so that the efficiency and wavelength stability of the transmitter is optimized.

Tunable resonator, tunable light source using the same, and method for tuning wavelength of multiple resonator

The object is to provide a highly reliable, high-performance, and low-price tunable light source and the like. The present invention comprises: a multiple resonator that oscillates with a wavelength where frequencies of three or more resonant elements with shifted cycles intersect; and a tunable device for controlling the resonant wavelength of the multiple resonator by simultaneously changing the respective optical path lengths of the plurality of resonant elements constituting the multiple resonator. The multiple resonator has a structure in which three resonant elements are connected in series; and provided that the optical path lengths of the resonant elements are L0, L1, L2, Vernier orders are M1>1, M2>1, the optical path lengths are defined as L 1 = M 1 M 1 - 1 ⁢ L 0 , ⁢ L 2 = M 2 M 2 - 1 , phase amount “Phase” is the changed optical path length standardized by one-wavelength of the optical path length, and the respective phase amount “Phase” of the two ring resonant elements whose ...

Light-emitting module

A light-emitting module according to the present invention contains a Peltier element driver, and a signal processor for controlling the Peltier element driver. The Peltier element driver is mounted on a first substrate, which directly attaches to the inner bottom surface of the housing, while the signal processor is mounted on the other substrate spaced to the first substrate. The first substrate and the other substrate are vertically integrated within the housing. This arrangement enables to encase the Peltier element driver and the signal processor in the housing with effective thermal dissipation.

Wavelength selectable laser with inherent and single-mode stability

A single-mode stabilized laser comprises a laser cavity having a round trip time tau r and a linewidth enhancement parameter alpha ; and a frequency routing device formed in the laser cavity comprising controllable frequency selective pathways such that selective gating of the frequency selective pathways causes selected lasing frequencies to be supported in the laser cavity separated by a frequency spacing DELTA FC, DELTA FC=1/ tau r. The frequency routing device has an optical grating having unequal length waveguides to form paths. The optical grating has arms, a time delay tau f between the longest path and the shortest path, and a grating bandwidth DELTA FF, DELTA FF=1/ tau f, at least one of (1) alpha and (2) tau r and tau f having sufficient value to stabilize the laser in single-mode operation. A method of turning on a laser having a waveguide grating to a stable operating condition comprises the steps of applying an initial current to a first amplifier and maintaining a second amplifier ...

Variable wavelength semiconductor laser

A semiconductor laser device has an active layer, a cladding layer, and a contact layer successively disposed on a semiconductor substrate. A pair of electrodes for passing a current parallel to the cladding and contact layers and perpendicular to the resonator direction of the active layer for heating the active layer are disposed opposite the stripe-shaped active layer. The pair of electrodes are disposed on the contact layer and the contact layer between the pair of electrodes is missing. One of the pair of electrodes may be disposed directly on the cladding layer. An improved wavelength change response property as a function of the active layer temperature controlling current flowing between the two electrodes is obtained. Further, the production of the laser is easy.

Method of tuning optical components integrated on a monolithic chip

A method of tuning optical components integrated on a monolithic chip, such as an optical transmitter photonic integrated circuit (TxPIC), is disclosed where a group of first optical components are each fabricated to have an operating wavelength approximating a wavelength on a standardized or predetermined wavelength grid and are each included with a local wavelength tuning component also integrated in the chip. Each of the first optical components is wavelength tuned through their local wavelength tuning component to achieve a closer wavelength response that approximates their wavelength on the wavelength grid.

Current control device and laser device

A current control device supplies a current to a semiconductor laser in order to output laser light to the semiconductor laser, and includes a current commander and a supplier. The current commander outputs a command value corresponding to a current value by increasing the command value with a lapse of time until reaching a target command value corresponding to a current value for outputting the laser light with a predetermined strength. The supplier supplies a current with a size corresponding to the command value output by the current commander to the semiconductor laser.

METHOD TO TUNE EMISSION WAVELENGTH OF LASER APPARATUS

A method includes steps of: acquiring a target wavelength; acquiring a drive condition of a wavelength tunable laser diode; driving the wavelength tunable laser diode based on the drive condition; acquiring a measured value of the first current measured by a first photodetector, a measured value of a second current measured by a second photodetector and a measured value of the drive condition; determining the measured value of the first current as a first target value; calculating a second target value of the second current from the measured value of the drive condition and the target value of the first current; and coinciding a ratio of the measured value of the first current with respect to the measured value of the second current, to a ratio of the first target of the first current with respect to the second target of the second current, by changing the drive condition.

MONITORING AND CONTROLLING TEMPERATURE ACROSS A LASER ARRAY IN A TRANSMITTER OPTICAL SUBASSEMBLY (TOSA) PACKAGE

The temperature at different locations along a multiplexed laser array may be monitored by sensing temperature at two locations within a transmitter optical subassembly (TOSA) package housing the laser array. The temperature at the two locations is used to determine a temperature tilt across the laser array. Estimated temperatures may then be determined at one or more other locations along the laser array from the temperature tilt. The estimated temperature(s) may then be used to adjust the temperature proximate the other locations, for example, for purposes of tuning lasers at those locations along the laser array to emit a desired channel wavelength. The TOSA package may be used in an optical transceiver in a wavelength division multiplexed (WDM) optical system, for example, in an optical line terminal (OLT) in a WDM passive optical network (PON).

INJECTION LOCKING OF GAIN SWITCHED DIODES FOR SPECTRAL NARROWING AND JITTER STABILIZATION

Pulse power can be stabilized by applying spectrally narrow pulses to a laser diode during gain switching. An injection locking laser with a narrow emission bandwidth is tuned to a gain bandwidth of a laser diode to be gain switched. The injection locking emission is pulsed to provide locking pulses that are attenuated and then coupled to a laser diode. A gain switching pulse drive is applied to the laser diode in the presence of the attenuated locking pulses. The gain switched output is then stabilized with respect to pulse energy and pulse amplitude, and is suitable as a seed pulse for lasers to be used in materials processing.

Thermally-controlled fiber optic tuning and isolating device

A tunable fiber optic component providing environmental isolation, thermal tuning, and mechanical tuning and a method of tuning a fiber optic component using application of substantially simultaneous varying of temperature and mechanical strain is disclosed. A method of using a tunable fiber optic component, for example, a distributed feedback fiber laser, to compensate variations in an optical system, and a method of making a tunable fiber optic component are also disclosed.

Methods of driving laser diodes, optical wavelength sweeping apparatus, and optical measurement systems

An optical wavelength sweeping apparatus is disclosed. The optical wavelength sweeping apparatus includes a laser diode having an active region including a thickness of less than 1 μm, a cross-section of less than 7 μm2, and a ratio of active region volume to total laser diode volume of less than 1/300, and a pulse generator coupled to the laser diode. The pulse generator is configured and operable to provide a current drive pulse to the laser diode to selectively and rapidly heat the active region and immediate vicinity to provide a peak increase in temperature of 30° C. or more at an end of the current pulse and to perform a wavelength sweep of emitted optical radiation which is greater than 5 nm. Methods of driving a laser diode and optical systems are disclosed, as are other aspects.

Control circuit for optoelectronic module with integrated temperature control

A microprocessor is used to control the temperature of a laser emitter and thereby regulate the wavelength of optical signals from the laser. A serial interface in the microprocessor provides input and output lines to a host device, and temperature lookup tables are stored in nonvolatile memory. Control logic processes information stored in the memory as well as information on operating conditions of the laser emitter to precisely control the temperature of the laser emitter. A thermo-electric cooler adjusts the temperature of the laser emitter.

Highly stable semiconductor lasers and sensors for III-V and silicon photonic integrated circuits

Building blocks are provided for on-chip chemical sensors and other highly-compact photonic integrated circuits combining interband or quantum cascade lasers and detectors with passive waveguides and other components integrated on a III-V or silicon. A MWIR or LWIR laser source is evanescently coupled into a passive extended or resonant-cavity waveguide that provides evanescent coupling to a sample gas (or liquid) for spectroscopic chemical sensing. In the case of an ICL, the uppermost layer of this passive waveguide has a relatively high index of refraction that enables it to form the core of the waveguide, while the ambient air, consisting of the sample gas, functions as the top cladding layer. A fraction of the propagating light beam is absorbed by the sample gas if it contains a chemical species having a fingerprint absorption feature within the spectral linewidth of the laser emission.

Optical transmitter operating burst mode and control method of optical transmitter operating burst mode

The present invention provides an optical transmitter including a semiconductor laser and a control method thereof for preventing crosstalk between channels in an NG-PON2 with a 100 GHz channel spacing by reducing a wavelength drift of the semiconductor laser. The wavelength drift occurs between a few nanoseconds and a few hundreds of nanoseconds from the beginning of a burst when the semiconductor laser is operated in a burst-mode.

TUNABLE LASER WITH ACTIVE MATERIAL ON AT LEAST ONE END FOR MONITORING PERFORMANCE

A laser comprising a laser cavity formed by a first optical reflector, a gain region, a second optical reflector having a plurality of reflection peaks, and at least one optically active region. The first mirror may be a DBR or comb mirror and the second mirror may be a comb mirror. The spectral reflectance of the second optical reflector is adjusted at least partially based on an electric signal received form the optically active region such that only one reflection peak is aligned with a cavity mode formed by the first and second reflector.

Tunable laser with multiple ring resonator and wavelength selective reflector

A tunable laser (10,50) has a multiple ring resonator (20,60) comprising a plurality of ring resonators (21,22,21,61,62) having respective ring-shaped waveguides and respective different optical path lengths, an input/output side optical waveguide (12,52) coupled to the multiple ring resonator, an optical input/output device (17,57) such as a laser diode coupled to the input/output side optical waveguide, a reflection side optical waveguide (14,54) coupled to the multiple ring resonator, an optical reflector (16,56) coupled to the reflection side optical waveguide for removing light at an unwanted wavelength and reflecting light at a required wavelength, and a wavelength varying mechanism (22h,23h,62h) for changing the resonant wavelength of the multiple ring resonator.

Method of controlling semiconductor laser

A semiconductor laser has a wavelength-selection portion whose refractive index is controllable with a heater (14). The starting sequence has a first step for adjusting the heat value of the heater (14) until it reaches a given value. Once this is established, a wavelength control sequence includes a second step (S4) for correcting the wavelength of the semiconductor laser according to the detection result of the oscillation wavelength of the semiconductor laser after the starting sequence. This allows an accurate restart even if the heater has deteriorated.

SEMICONDUCTOR LASER, LASER MODULE, OPTICAL COMPONENT, LASER DEVICE, AND MANUFACTURING METHOD AND CONTROL METHOD OF SEMICONDUCTOR LASER

PROBLEM TO BE SOLVED: To provide a tunable semiconductor laser capable of stabilizing a mode of a laser oscillation with a newly structured SG-DR waveguide. SOLUTION: The semiconductor laser (200) comprises a first region having a diffraction grating (2), and a first diffraction grating region (3) having a plurality of segments having a second region connected to the first region and becoming a space part. At least two optical lengths out of the plurality of second regions are different each other and refraction factors of each segment are respectively variable. The difference of at least two optical lengths out of the plurality of second regions makes a peak reflection intensity of a longitudinal mode in the first diffraction grating region have a wavelength dependence. This can provide a stable laser oscillation in the wavelength range with the peak reflection insensity of the longitudinal mode in the first diffraction grating region relatively large. COPYRIGHT: (C)2007,JPO&INPIT ...

ЛАЗЕРНАЯ СИСТЕМА

... 1. Лазерная система в установке задающего генератора/усилителя мощности (МОРА), содержащая импульсный задающий диодный генератор и накачиваемый активный оптоволоконный усилитель мощности, стоящий после задающего генератора, причем, по существу, все каналы лазерного света являются оптическими волокнами. 2. Лазерная система по п.1, дополнительно содержащая блок детектора для входящего импульсного лазерного света, функционально подключенный к блоку оценки, осуществляющему оценку множества входящих лазерных импульсов. 3. Система по п.1, в которой активный оптоволоконный усилитель мощности накачивается диодом накачки. 4. Система по п.1, в которой активный оптоволоконный усилитель мощности модулируется по коэффициенту усиления. 5. Система по п.1, в которой активный оптоволоконный усилитель мощности модулируется по коэффициенту усиления посредством, по меньшей мере, одного из: изменения интенсивности света накачки, изменения спектра света накачки, изменения ширины импульса накачки, длины активного ...

HYDRIDLASER FUER OPTISCHES NACHRICHTENWESEN.

Semiconductor diode laser

In the case of a semiconductor diode laser having a reinforced active part (6) and a passive part (7) on which the light of the active part acts, it is provided that the thermal balances resulting from heating by the current source and cooling by the couplings to the heat sink (cooling base) (4) produce different temperature changes in the passive part (7) and active part (6) when the laser is being tuned by varying the supply current at the operating point, such that the current tuning rate of the DBR resonant frequency is equal to or less than the current tuning rate of the modes in the case of a passive part (7) in the form of a DBR reflector, and such that the current tuning rate of the modes of the overall resonator is approximately equal to the current tuning rate of the reinforcement in the case of a broadband passive part. ...

Optoelectronic device and method of manufacture thereof

The silicon-on-insulator wafer platform includes a waveguide 104 formed in the silicon layer and a thermal isolation cavity 102 in the surface of the SOI wafer for mounting a micro transfer printed III-V semiconductor optoelectronic device coupon 112. The III-V semiconductor device has a waveguide which is coupled to the silicon waveguide. A region of a bed of the cavity, located between the III-V semiconductor device and the substrate, includes a patterned surface 103, which is configured to interact with an optical signal within the III-V semiconductor waveguide of the III-V semiconductor device. The patterned surface is used to form a grating 103 for a III-V distributed Bragg reflector laser. The thermally isolated cavity may incorporate a heater 701 and a heatsink 801 for temperature control of the optoelectronic device.

Lockerless tuneable DBR laser

A distributed Bragg reflector (DBR) laser has a phase section 502 in a cavity, a DBR section 501 comprising a frequency tuning system having a resistance heater, and a photodetector 509. A controller 510 is configured to cause the phase section 502 to apply a dither to the optical path length of the cavity, or cause the frequency tuning system to apply a dither to a Bragg frequency of the DBR section; to use the detector 509 to monitor light intensity transmitted from the laser cavity via the DBR section 501 during the dither; determine deviation from longitudinal mode centre operation based on monitored intensity; reduce the deviation by causing phase section 502 to adjust the optical path length of the cavity; and control laser output frequency by adjusting the power of the resistance heater. The laser is tuned without a frequency locker. Laser drifts are prevented, reducing mode hops.

Active mode centre control

A distributed Bragg reflector (DBR) laser has a phase section 502 in a cavity, a DBR section 501, and a detector 509, such as a photodiode. A controller 510 is configured to cause the phase section 502 to apply a dither to the optical path length of the cavity, or cause a frequency tuning system (may be thermal or electronic) of the DBR section 501 to apply a dither to a Bragg frequency; to use the detector 509 to monitor light intensity transmitted from the laser cavity via the DBR section 501, during the dither; determine deviation from longitudinal mode centre operation, based on the monitored intensity; and reduce the deviation by causing the phase section 502 to adjust the optical path length of the cavity, or causing the frequency tuning system to adjust the Bragg frequency. Laser drifts are prevented, reducing risk of mode jumps, and extending laser lifetime.

Thin film resistors for tuning semiconductor lasers

A thin film resistor for optoelectronic integrated circuits is described. A stable low resistance, thin film resistor comprising a bilayer of platinum on titanium is provided. Advantageously, the resistive layer is protected by a layer of dielectric, e.g. silicon dioxide or silicon nitride to reduce degradation from humidity an under high temperature operation at 300 DEG C. or more. The resistor may be formed on various substrates, including silicon dioxide, silicon nitride and semiconductor substrates. Applications for optoelectronic integrated circuits include integrated resistive heaters for wavelength fine tuning of a semiconductor laser array.

Waveguide Structure

Optoelectronic device and method of manufacture thereof

Laser

A laser comprising a photonic component comprising a gain medium and a waveguide platform comprising a distributed Bragg reflector, (DBR) section. The photonic component is optically coupled to the waveguide platform. One or more thermal heaters are positioned at the DBR section of the waveguide platform, and/or at the phase section of the waveguide platform located between the gain medium and the DBR section.

WAVELENGTHVARIABLE DIODE LASER ELEMENT, AND DEVICE AND PROCEDURE FOR ITS CONTROL

A LASER DIODE WITH AN AMPLIFICATION SECTION THAT HAS A VARYING INDEX OF REFRACTION

FREQUENCY LOCKER

Pump wavelength tuning of optical amplifiers and use of same in wavelength division multiplexed systems

Optical transmitter comprising a stepwise tunable laser

WAVELENGTH TUNABLE LASER

A wavelength tunable laser comprises a multiple ring resonator, an input/output side waveguide coupled to a ring resonator, a reflection side waveguide coupled to a ring resonator, a multiple ring resonator, a PLC substrate where the input/output side waveguide and the reflection side waveguide are formed, a high reflection film set on the reflection side waveguide, a SOA connected to the input/output side waveguide through a anti-reflection film, a film heater which is placed above a ring waveguide for wavelength tuning in the PLC substrate and provides heat to the ring waveguide for wavelength tuning, and a adiabatic groove, which restrain conducting heat provided by the film heater to the PLC substrate except the ring waveguide for wavelength tuning.

THERMAL COMPENSATION FOR BURST-MODE LASER WAVELENGTH DRIFT

An apparatus comprising a burst-mode laser(610) comprising an active layer(720) and configured to emit an optical signal during a burst period, wherein a temperature change of the burst-mode laser(610) causes the optical signal to shift in wavelength, and a heater(620) thermally coupled to the active layer(720) and configured to reduce a wavelength shift of the optical signal during the burst period by applying heat to the active layer(720) based on timing of the burst period.

METHOD AND DEVICE FOR GAS ANALYSIS USING AN INTERFEROMETRIC LASER

The invention relates to design of an interferometric laser and a method for analyzing gas with this, preferably methane, ethane, propane, butane, pentane, hexane, heptane, ethylene, dichloromethane, isooctane, benzene, xylenes, hydrazine, formaldehyde, N2O, NO2, CO2, CO, HF, O3, HI, NH3, SO, HBr, H2S, HCN, preferably a tunable interferometric laser which can sweep a spectrum.

MULTIWAVELENGTH QUANTUM CASCADE LASER VIA GROWTH OF DIFFERENT ACTIVE AND PASSIVE CORES

Disclosed is a method of forming a laser source capable of producing mid-IR laser radiation comprises growing a first core structure on a substrate, etching away the first core structure in one or more locations, and growing a second core structure on the substrate. At least one of the core structures comprises a quantum cascade gain medium emitting at a frequency within the range from 3-14 µm. Also disclosed is a laser source capable of producing mid-IR laser radiation comprising a quantum- cascade core positioned on a substrate for emitting within the range from 3-14 µm and a second core on the substrate positioned in-plane relative to the first core. The second core is one of a) a passive waveguide core b) a second quantum-cascade core and c) a semiconductor active core region.

MULTI-BEAM SEMICONDUCTOR LASER AND METHOD FOR PRODUCING THE SAME

This is disclosed a multi-beam semiconductor laser comprising: an active layer; a first and second cladding layer sandwiching the active layer,the second cladding layer being made of a first material; a contact layer provided on the second cladding layer; a current block layer provided in the second cladding layer, the current block layer being made of a second material and being spaced from the active layer with a predetermined distance; a dividing part provided above the current block for physically dividing the contact layer into two areas; and electrodes respectively provided on the divided areas of the contact layer.

FIBER-OPTIC AMPLIFIER WITH CONTROL OF THE PUMP LIGHT WAVELENGTH

FIBER-OPTIC AMPLIFIER WITH CONTROL OF THE PUMP LIGHT WAVELENGTH In fiber-optic amplifiers, for example those including a light waveguide piece (1) doped with Er3+, the wavelength of the pump light generated by the pump light source (2) must lie as precisely as possible at that wavelength that is desired as the pump light wavelength for the amplifying light waveguide piece (1). Deviations from this wavelength considerably adversely influence the performance of the optical amplifier. According to the invention, the fiberoptic amplifier includes a control device which regulates the wavelength of the pump light generated by the pump light source (2) to the absorption maximum lying at the desired wavelength. Preferably this is done in that part of the pump light is coupled into a reference light waveguide piece (10) which has its maximum absorption at the same wavelength as the amplifying light waveguide piece (1) and in that the absorption in the reference light waveguide piece (10) is used ...

METHOD AND MEANS FOR CONTROLLING THE FREQUENCY AND POWER OUTPUT OF A TUNABLE DIODE LASER

METHOD AND MEANS FOR CONTROLLING THE FREQUENCY AND POWER OUTPUT OF A TUNABLE DIODE LASER In a laser emitter-receiver system, a tunable diode laser provides a beam of coherent light having a selected frequency. An infrared detector spaced from the source detects the light transmitted along the beam path between the source and the detector and produces a corresponding output in response thereto. A heating laser provides radiation to the diode laser to heat, and thereby to change the frequency of, the latter laser. The radiation from the heating laser is varied periodically to modulate the intensity of the radiation incident on the diode laser thereby to frequency-modulate the diode laser output over a selected tuning range. A controller responsive to the detector output regulates the current to the diode laser to minimize selected frequency components of the modulated light beam from that laser so that the power output of the diode laser varies minimally when that laser is tuned over the ...

FIBER OPTIC GYROSCOPE SOURCE WAVELENGTH CONTROL

A pumped rare-earth fiber source wavelength control device, having source wavelength control effected by pump source wavelength and power control. The maintaining of pump wavelength and power control can be attained several ways such as by use of a wavelength sensitive coupler, a short length of fiber having an embedded grating, and a modulated grating embedded fiber.

PRODUCING LASER LIGHT OF DIFFERENT WAVELENGTHS

In a tunable laser device a plurality of basically identical lasers are arranged adjacent to each other in a line or row on a common substrate. The lasers can be DFB--type and they have different emission wavelengths, obtained from e.g. different pitches of gratings which define the wavelengths of the respective lasers. The lasers can be activated to emit light independently of each other by supplying electrical current to contacts located on the top sides of the lasers. When a laser is activated, the other lasers are biased, so that lasers located at one side of the active laser will be transparent to the emitted light, which can then travel from the lasers through an electrooptic modulator, and the lasers located at the other side will absorb the light. By controlling the temperature, the wavelength of emitted light can be finely adjusted. Such a laser device has a compact structure, is fairly insensitive to variations of the used drive currents and can in a simple way be adjusted to ...

Method of evaluating initial parameters and target values for feedback control loop of wavelength tunable system

Tunable laser

A tunable laser includes an optical cavity comprising a first and second mirror. A gain medium is positioned in the optical cavity that generates stimulated emission in the optical cavity when biased. A thermally tunable optical filter is positioned in the optical cavity that is heated to a temperature that selects a desired optical mode of the optical cavity. A thermally tunable optical phase retarder is positioned in the optical cavity that is heated to a temperature which changes an optical path length in the optical cavity by an amount corresponding to a resonant frequency of the tunable optical filter so that a phase-matching condition of the optical cavity is shifted to the desired optical mode of the optical cavity selected by the thermally tunable optical filter.

Variable light controlling device and variable light controlling method

A variable light controlling device comprising a substrate, an optical waveguide disposed on the substrate, a first heater and a second heater to change the optical waveguide's temperature is fabricated. And a total amount of the power supplied to the first and the second heater, or a total amount of heat emitted from both of the first and second heater, is maintained substantially constant. Then, the substrate is protected from temperature changes, thereby, stable and quick wavelength tuning operations are realized.

DEVICE HAS SELECTIVE COUPLER IN WAVELENGTH FOR COLLECTION OF the LIGHT EMITTED BY a LASER SOURCE.

L'invention concerne un dispositif de collection de la lumière émise par une source laser (1), comprenant un guide d'onde optique (2) disposé de façon à recueillir par couplage un signal lumineux émis par la source laser. Le guide d'onde (2) comprend une boucle couplée à la source laser (1) en deux points de couplage et permettant de récupérer des modes optiques circulant en sens inverse du sens désiré pour le signal de sortie du dispositif.

VARIABLE LIGHT CONTROL DEVICE AND A VARIABLE LIGHT CONTROL METHOD FOR SHORTENING THE TIME TAKEN UNTIL OPTICAL CHARACTERISTICS ARE STABLIZED IF A WAVELENGTH IS CHANGED ON THE BASIS OF A THERMO-OPTIC EFFECT

PURPOSE: A variable light control device and a variable light control method are provided to realize a quick wavelength tuning operation by preventing the temperature change of a substrate even if power supplied to a first heater is changed during tuning. CONSTITUTION: A variable light control device is composed of a substrate(11); optical waveguides(13-1,13-2,13-3) disposed on the substrate; first heaters(15-1,15-2) disposed near the optical waveguide; and second heaters(16-1,16-2) separated from the first heater. The sum of power supplied to both the first and second heaters is constantly maintained. The first heater is disposed on a first clad having a core formed inside and the second heater is disposed on a second clad in which the core is not formed. © KIPO 2007 ...

Avstämbar optisk parametrisk oscillator

A METHOD AND A COUPLING TO CHANGE THE WAVELENGTH OF AN OPTICAL TRANSMITTER IN A SYSTEM USING WAVELENGTH DIVISION MULTIPLEXING

Cette invention repose sur l'idée que la longueur d'onde d'un émetteur laser, dans un système à multiplexage par répartition en longueur d'onde, peut être modifiée de manière commandée en induisant une modification prédéterminée et précise dans le signal de commande (TEC) du courant de commande de l'unité de refroidissement. Cela se traduit par une modification commandée de l'action réfrigérante ou chauffante de l'unité de refroidissement. Il en découle une modification prédéterminée de la longueur d'onde de la lumière qui est émise par le laser. Le circuit de régulation de température permet de maintenir la température du laser et, partant, la longueur d'onde exactement à la nouvelle valeur. Pour chaque longueur d'onde voulue, un ensemble de paramètres comprenant une valeur de température du laser, une valeur de puissance du laser et des valeurs de polarisation pour la modulation du laser prédéterminées, est préalablement sauvegardé et stocké. Lorsque la longueur d'onde du laser doit être ...

MODULAR FIBER-BASED CHIRPED PULSE AMPLIFICATION SYSTEM

A modular ultrafast pulse laser system is constructed of individually pre-tested components manufactured as modules. The individual modules include an oscillator, pre-amplifier and power amplifier stages, a non-linear amplifier, and a stretcher and compressor. The individual modules can typically be connected by means of simple fiber splices.

METHOD FOR SYNTONIZING THE WAVE LENGTHS OF AN ARRANGEMENT OF OPTOELECTRONIC COMPONENTS

The invention relates to a method for syntonizing an arrangement of optoelectronic components, said arrangement consisting of at least two optoelectronic components. The aim of the invention is to minimise the cost. According to the inventive method, the characteristic wave length for each optoelectronic component is set by selectively adjusting the amount of resistance of the conductor of the resistance heating (H) or the amount of resistance of a resistance mechanism (RM) connected upstream of the resistance heating (H). The inventive method is suitable for syntonizing the wave lengths of semiconductor lasers, optical amplifiers, filters, wavelength multiplexers and wave guides.

OPTICAL TRANSMITTER OPERATING BURST MODE AND CONTROL METHOD OF OPTICAL TRANSMITTER OPERATING BURST MODE

The present invention provides an optical transmitter including a semiconductor laser and a control method thereof for preventing crosstalk between channels in an NG-PON2 with a 100 GHz channel spacing by reducing a wavelength drift of the semiconductor laser. The wavelength drift occurs between a few nanoseconds and a few hundreds of nanoseconds from the beginning of a burst when the semiconductor laser is operated in a burst-mode.

VARIABLE LIGHT CONTROLLING DEVICE AND VARIABLE LIGHT CONTROLLING METHOD

A variable light controlling device comprising a substrate, an optical waveguide disposed on the substrate, a first heater and a second heater to change the optical waveguide's temperature is fabricated. And a total amount of the power supplied to the first and the second heater, or a total amount of heat emitted from both of the first and second heater, is maintained substantially constant. Then, the substrate is protected from temperature changes, thereby, stable and quick wavelength tuning operations are realized.

Laser diode pump wavelength sensing and control apparatus and method

A laser diode pumped laser has a laser diode wavelength sensing and control apparatus. A laser medium is mounted in a laser cavity and has a laser diode pump having a laser diode or laser diode array having an output of a predetermined wavelength for exciting the laser medium. An optical radiation detector is coupled to the output of the laser medium to receive and measure the radiation from the laser diode transmitted through the laser medium and a detector bias and signal measurement circuit is coupled to the optical radiation detector to receive signals therefrom and generate an output signal responsive to the optical radiation detector signals and to apply the generated signals to the laser diode power supply (or to diode heaters) to vary the power supply output to vary the laser diode wavelength to maintain the laser diode wavelength at the absorption peak of the laser medium. A method of sensing and controlling the laser diode pump wavelength for a laser includes selecting a laser ...

Monolithic array of independently addressable diode lasers

A monolithic array of two or more independently addressable, closely spaced diode lasers having low thermal, electrical, and optical crosstalk. An isolation groove is formed between the adjacent laser elements, which are defined by rib loaded waveguides created by etching mesas above a planar active multilayer waveguide. Separate electrical connections to the ribs, and a common electrical connection to the substrate, enable individual addressing of each laser element. Selectively added blocking layers and/or insulating layers are added to the structure to provide improved electrical and/or thermal isolation.

SEMICONDUCTOR LASER

A hybrid single or multi-wavelength laser using an optical gain element, such as a semiconductor optical amplifier (SOA), for example a QD RSOA, and a semiconductor, e.g. silicon, photonics chip is demonstrated. A plurality, e.g. four, lasing modes at a predetermined, e.g. 2 nm, spacing and less than 3 dB power non-uniformity may be observed, with over 20 mW of total output power. Each lasing peak can be successfully modulated at 10 Gb/s. At 10−9 BER, the receiver power penalty is less than 2.6 dB compared to a conventional commercial laser. An expected application is the provision of a comb laser source for WDM transmission in optical interconnection systems.

Method and apparatus for suppressing stimulated brillouin scattering in fiber links

Method and apparatus for producing a laser output having stimulated Brillouin scattering (SBS) suppression characteristics. An excitation signal is provided to an optical path length adjustment element in an external cavity laser to modulate the optical path length of the cavity. This produces a laser output having a wavelength modulation frequency and line width that are a function of the frequency and amplitude of the excitation signal. Under appropriate modulation frequency and line width combinations, the laser output comprises an optical signal with SBS suppression characteristics, thus enabling a higher power signal to be launched into a fiber link since the SBS suppression characteristics raise the SBS threshold of the link. The optical path length modulation also produces an intensity (amplitude) modulation in the laser output. A detector is employed to produce a feedback signal indicative of the intensity modulation that is used for tuning the laser in accordance with a wavelength ...

Highly stable semiconductor lasers and sensors for III-V and silicon photonic integrated circuits

Building blocks are provided for on-chip chemical sensors and other highly-compact photonic integrated circuits combining interband or quantum cascade lasers and detectors with passive waveguides and other components integrated on a III-V or silicon. A MWIR or LWIR laser source is evanescently coupled into a passive extended or resonant-cavity waveguide that provides evanescent coupling to a sample gas (or liquid) for spectroscopic chemical sensing. In the case of an ICL, the uppermost layer of this passive waveguide has a relatively high index of refraction that enables it to form the core of the waveguide, while the ambient air, consisting of the sample gas, functions as the top cladding layer. A fraction of the propagating light beam is absorbed by the sample gas if it contains a chemical species having a fingerprint absorption feature within the spectral linewidth of the laser emission.

METHOD FOR SYNTONIZING THE WAVE LENGTHS OF AN ARRANGEMENT OF OPTOELECTRONIC COMPONENTS

Frequency tunable terahertz transceivers and method of manufacturing dual wavelength laser

Provided are a frequency tunable terahertz transceiver and a method of manufacturing a dual wavelength laser. The frequency tunable terahertz transceiver includes: a dual wavelength laser including two distributed feedback lasers that are manufactured in one substrate and output optical signals of respectively different wavelengths; and an optical device receiving the outputted optical signals to generate a terahertz wave.

Wavelength tunable laser diode

A wavelength tunable laser diode (LD) is disclosed. The LD provides a SG-DFB region and a CSG-DBR region. The SG-DFB region shows a gain spectrum with a plurality of gain peaks, while, the CSG-DBR region shows a reflection spectrum with a plurality of reflection peaks. The LD may emit light with a wavelength at which the one of the gain peaks and one of the reflection peaks coincides. In the present LD, both the gain spectrum and the reflection spectrum are modified by adjusting the temperature of the SG-DFB region and that of the CSG-DBR region independently.

Semiconductor optical integrated device

A semiconductor optical integrated device includes a substrate having a main surface with a first and second regions arranged along a waveguiding direction; a gain region including a first cladding layer, an active layer, and a second cladding layer arranged on the first region of the main surface; and a wavelength control region including a third cladding layer, an optical waveguide layer, and a fourth cladding layer arranged on the second region of the main surface and including a heater arranged along the optical waveguide layer. The substrate includes a through hole extending from a back surface of the substrate in the thickness direction and reaching the first region. A metal member is arranged in the through hole. The metal member extends from the back surface of the substrate in the thickness direction and is in contact with the first cladding layer.

Method to switch emission wavelength of tunable laser diode

The method to change the emission wavelength of a tunable LD is disclosed. In an ordinary state, the method monitors conditions not only relating to determine the emission wavelength but conditions independent of the emission wavelength by an ordinary A/D-C implemented within the controller. Responding to an instruction to switch the emission wavelength, the controller only monitors the former conditions affecting the determination of the emission wavelength. The sampling rate of the ordinary A/D-C is equivalently enhanced without installing an additional A/D-C.

METHODS AND APPARATUS FOR TEMPERATURE TUNING OF SEMICONDUCTOR LASERS

The present technology relates to a fast and efficient heating element based on a thick heterostructure which is monolithically integrated in close proximity to one or more components of a photonic or an electronic circuit. Inventive embodiments also relate to methods of use illustrative heating elements to control or tune the characteristics of the electronic or photonic component(s). Inventive embodiments may be particularly useful in the fast spectral tuning of the emission wavelength of single mode QCLs. 1. An apparatus , comprising:a substrate;a semiconductor device integrated onto the substrate, the semiconductor device having at least one temperature-tunable property; anda heterostructure heater, integrated onto the substrate and in thermal communication with the semiconductor device, to heat the semiconductor device so as to vary the at least one temperature-tunable property of the semiconductor device.2. The apparatus of claim 1 , wherein the heterostructure heater is configured to transform electrical power into heat claim 1 , via the Joule effect claim 1 , with an efficiency of more than about 25%.3. The apparatus of claim 1 , wherein the semiconductor device comprises at least one of a quantum cascade laser (QCL) claim 1 , an interband cascade laser claim 1 , a quantum well laser claim 1 , a distributed feedback (DFB) laser claim 1 , and a distributed Bragg reflector (DBR) laser claim 1 , and wherein the at least one temperature-tunable property comprises an output wavelength of the at least one of the QCL claim 1 , the interband cascade laser claim 1 , the quantum well laser claim 1 , the DFB laser claim 1 , and the DBR laser.4. The apparatus of claim 3 , wherein the heterostructure heater is configured to heat the at least one of the QCL claim 3 , the interband cascade laser claim 3 , the quantum well laser claim 3 , the DFB laser claim 3 , and the DBR laser so as to vary the output wavelength of the at least one of the QCL claim 3 , the interband ...

Directly-coupled wavelength-tunable external cavity laser

Disclosed is a directly-coupled wavelength-tunable external cavity laser including a gain medium that generates an optical signal by an applied bias current; an optical waveguide structure that is coupled to the gain medium to form a minor surface and causes lasing in the mirror surface when the applied bias current has a threshold or higher; and a radio frequency transmission medium that adds a radio frequency signal to the applied bias current to adjust an operating speed of the optical signal.

Slot waveguide structure for wavelength tunable laser

Exemplary embodiments provide a wavelength tunable laser device and methods using the wavelength tunable laser device for a laser tuning. An exemplary wavelength tunable laser device can include an active gain element, a slot waveguide structure, and a wavelength tuning structure including heating elements disposed around the grating structure for a wavelength selection.

Optical Amplifier and Optical Transmission System

An optical amplifying apparatus that amplifies an optical signal, including an input section whereto the optical signal is inputted, a laser light source that generates laser light, the laser light source including an uncooled semiconductor laser device, an optical fiber that amplifies the optical signal by a stimulated emission based on the laser light from the laser light source, an output section that outputs the optical signal amplified by the optical fiber, and a passive optical component disposed between the optical fiber and the output section. The laser light source is thermally coupled to the optical fiber and/or the passive optical component via a thermally conductive medium. An oscillating wavelength of the laser light source is varied by increasing a temperature of the laser light source with heat generated by the optical fiber and/or the passive optical component. 1. An optical amplifying apparatus that amplifies an optical signal , comprising:an input section whereto the optical signal is inputted;a laser light source that generates laser light, the laser light source including an uncooled semiconductor laser device;an optical fiber that amplifies the optical signal by a stimulated emission based on the laser light from the laser light source;an output section that outputs the optical signal amplified by the optical fiber; anda passive optical component disposed between the optical fiber and the output section,the laser light source being thermally coupled to the optical fiber and/or the passive optical component via a thermally conductive medium,an oscillating wavelength of the laser light source being varied by increasing a temperature of the laser light source with heat generated by the optical fiber and/or the passive optical component.2. The optical amplifying apparatus according to claim 1 , wherein the heat generated by the optical fiber and/or the passive optical component is transferred to the laser light source claim 1 , and a wavelength band ...

Self-Injection Locking Using Resonator On Silicon Based Chip

Disclosed are devices, methods, and systems for controlling output of a laser. An example device can comprise a first portion comprising a gain element and a second portion comprising a silicon material. The second portion can comprise a waveguide configured to receive light from the gain element, an optical resonator configured to at least partially reflect light back to the gain element via the waveguide, and a first tuning element configured to tune a resonant frequency of the optical resonator. 1. A device , comprising:a first portion comprising a gain element; and a waveguide configured to receive light from the gain element;', 'an optical resonator configured to at least partially reflect light back to the gain element via the waveguide; and', 'a first tuning element configured to tune a resonant frequency of the optical resonator., 'a second portion comprising a silicon material, wherein the second portion comprises2. The device of claim 1 , wherein the optical resonator is tuned by the first tuning element to cause one or more of: (1) output of a single longitudinal mode by the gain element claim 1 , (2) output of a single transversal mode by the gain element claim 1 , (3) narrowing of a linewidth of a lasing mode of the gain element claim 1 , or (4) tuning a frequency of the gain element.3. The device of claim 1 , wherein the optical resonator comprises a ring resonator.4. The device of claim 1 , wherein the gain element comprises one or more of a Fabry-Perot laser claim 1 , a multimodal laser claim 1 , or a multimodal Fabry-Perot laser.5. The device of claim 1 , wherein one or more of the waveguide or the optical resonator comprises a dielectric material disposed on the silicon material claim 1 , and wherein the dielectric material comprises silicon nitride.6. The device of claim 1 , wherein the second portion comprises one or more of a chip claim 1 , an integrated circuit claim 1 , or a monolithically integrated portion.7. The device of claim 1 , wherein ...

WAVELENGTH-TUNABLE III-V/Si HYBRID OPTICAL TRANSMITTER

An optical transmitter includes a reflective semiconductor optical amplifier (RSOA) coupled to an input end of a first optical waveguide. An end of the first optical waveguide provides a transmitter output for the optical transmitter. Moreover, a section of the first optical waveguide between the input end and the output end is optically coupled to a ring modulator that modulates an optical signal based on an electrical input signal. A passive ring filter (or a 1×N silicon-photonic switch and a bank of band reflectors) is connected to provide a mirror that reflects light received from the second optical waveguide back toward the RSOA to form a lasing cavity. Moreover, the ring modulator and the passive ring filter have different sizes, which causes a Vernier effect that provides a large wavelength tuning range for the lasing cavity in response to tuning the ring modulator and the passive ring filter. 1. An optical transmitter , comprising:a reflective semiconductor optical amplifier (RSOA);a ring modulator that modulates an optical signal based on an electrical input signal;a first optical waveguide with an input end and an output end, wherein the input end is coupled to the RSOA, wherein the output end provides a transmitter output for the optical transmitter, and wherein a section of the first optical waveguide between the input end and the output end is optically coupled to the ring modulator;an array of N narrow-band reflectors, wherein each narrow-band reflector has a different center wavelength;a 1×N silicon-photonic switch, having an input port and N output ports, wherein each output port is coupled to a different narrow-band reflector in the array of N narrow-band reflectors;a second optical waveguide with a first end optically coupled to the ring modulator and a second end coupled to the input port of the 1×N silicon-photonic switch; andan adjustment mechanism that facilitates adjusting a frequency of the optical transmitter in discrete increments by ...

COMPACT TUNABLE LASER DEVICE

The present invention relates to a compact tunable laser device that can change the oscillation laser wavelength. The laser device includes: a laser diode chip that emits laser light; an optical feedback-partial reflective mirror that feeds some of light emitted from the laser diode chip back to the laser diode chip by reflecting it; a collimating lens that is disposed in a light path between the laser diode chip and the optical feedback-partial reflective mirror and collimates light emitted from the laser diode chip a tunable-selective filter of which the transmissive wavelength changes in accordance with temperature; and a 45°-reflective mirror that changes laser light traveling horizontally to a package bottom into laser light traveling perpendicular to the package bottom, wherein the laser diode chip or the tunable-selective filter is disposed on a thermoelectric element and has an oscillation wavelength changing in accordance with a change in temperature of the thermoelectric element 1. A semiconductor laser device comprising:{'b': '100', 'a laser diode chip () that emits laser light;'}{'b': 500', '100', '100, 'an optical feedback-partial reflective mirror () that feeds some of light emitted from the laser diode chip () back to the laser diode chip () by reflecting it;'}{'b': 200', '100', '500', '100, 'a collimating lens () that is disposed in a light path between the laser diode chip () and the optical feedback-partial reflective mirror () and collimates light emitted from the laser diode chip ();'}{'b': '300', 'a tunable-selective filter () of which the transmissive wavelength changes in accordance with temperature; and'}{'b': '400', 'a 45°-reflective mirror () that changes laser light traveling horizontally to a package bottom into laser light traveling perpendicular to the package bottom,'}{'b': 100', '300', '900', '900, 'wherein the laser diode chip () or the tunable-selective filter () is disposed on a thermoelectric element () and has an oscillation ...

TRANSIENT WAVELENGTH DRIFT REDUCTION IN SEMICONDUCTOR LASERS

This application relates to a laser assembly displaying self-heating mitigation. The laser assembly comprises a semiconductor laser and a drive unit for driving the semiconductor laser. The semiconductor laser includes a first semiconductor region for generating or modulating an optical signal in response to a first drive current that is applied to the first semiconductor region, and a heating region that is arranged in proximity to the first semiconductor region and electrically insulated from the first semiconductor region. The drive unit is configured to generate the first drive current and a second drive current, apply the first drive current to the first semiconductor region during respective transmission periods of the semiconductor laser, and apply the second drive current to the heating region in intervals between successive transmission periods. 1. A laser assembly comprising a semiconductor laser and a drive unit for driving the semiconductor laser , a first semiconductor region for generating or modulating an optical signal in response to a first drive current that is applied to the first semiconductor region;', 'a heating region that is arranged in proximity to the first semiconductor region and electrically insulated from the first semiconductor region,, 'wherein the semiconductor laser compriseswherein the drive unit is configured to generate the first drive current and a second drive current, apply the first drive current to the first semiconductor region during respective transmission periods of the semiconductor laser, and apply the second drive current to the heating region in intervals between successive transmission periods.wherein the drive unit is configured to generate the first drive current on the basis of an input signal comprising a data signal indicative of data to be transmitted by means of the optical signal; and a drive circuit for generating the first drive current based on the data signal;', 'an averaging circuit for generating an ...

METHOD FOR TUNING EMISSION WAVELENGTH OF LASER DEVICE

A method for tuning an emission wavelength of a laser device, including: acquiring a drive condition of a wavelength tunable laser diode to make the wavelength tunable laser diode oscillate at a wavelength from a memory; driving a first thermo-cooler and a first heater based on the drive condition of the wavelength tunable laser diode; determining whether respective control values of the first thermo-cooler and the first heater are reached within a first range of target values; and driving a gain region after the control values have been reached within the first range. 1. A method for tuning an emission wavelength of a laser device including:a wavelength tunable laser diode including a gain region, and a first wavelength selection region integrated with a gain region, and a first heater;a first thermo-cooler on which the wavelength tunable laser diode is mounted, the first thermo-cooler being configured to control a temperature of the wavelength tunable laser diode, the method comprising:acquiring a drive condition of the wavelength tunable laser diode to make the wavelength tunable laser diode oscillate at a wavelength from a memory;driving the first thermo-cooler and the first heater based on the drive condition of the wavelength tunable laser diode;determining whether respective control values of the first thermo-cooler and the first heater are reached within a first range of target values; anddriving the gain region after the control values have been reached within the first range.2. The method of claim 1 ,wherein the first heater includes a plurality of heaters, andwherein the driving the gain region is performed after all the control values of the plurality of heaters are reached.3. The method of claim 1 , acquiring a drive condition of the second heater from the memory;', 'driving the second heater based on the drive condition of the second heater; and, 'wherein the wavelength tunable laser diode further includes a second wavelength selection region and a ...

METHOD OF EVALUATING INITIAL PARAMETERS AND TARGET VALUES FOR FEEDBACK CONTROL LOOP OF WAVELENGTH TUNABLE SYSTEM

A method of determining initial parameters and target values for tuning an emission wavelength of a wavelength tunable laser capable of emitting laser light in a substantial wavelength range is disclosed. The method iterates an evaluation of initial parameters and target values at target wavelengths in a preset order. The evaluation includes steps of supplying empirically obtained parameters to the t-LD, confirming whether the t-LD generates an optical beams, determining the initial parameters and the target values by carrying out feedback loops of the AFC and the APC when the t-LD generates the optical beam, or shifting the wavelength range so as to exclude the current target wavelength when the t-LD generates no optical beam. 1. A method of ranking a wavelength tunable laser (t-LD) that provides a sampled grating distributed feedback (SG-DFB) region , a chirped sampled grating distributed feedback reflector (CSG-DBR) region , and a semiconductor optical amplifier (SOA) region , the t-LD being mounted on a thermo-electric cooler (TEC) that varies a temperature of the t-LD , the CSG-DBR region providing a heater that varies a temperature of the CSG-DBR region , the t-LD emitting laser light whose wavelength being to be discretely tunable within a wavelength range by setting parameters in the t-LD , the SG-DFB region having an optical gain that shows a maximum in a center of the wavelength range and becomes relatively smaller in peripheries of the wavelength range , the method comprising steps of:driving the t-LD nearby a shortest wavelength and nearby a longest wavelength within the wavelength range by setting parameters that are empirically determined;confirming whether the t-LD generates an optical beam whose wavelength is around the shortest wavelength and the longest wavelength in the wavelength range with and power is around a designed power, degrading a rank of the t-LD, and', 'iterating a step of driving the t-LD at a wavelength next to the shortest ...

OPTICAL ELEMENT AND LIGHT GENERATING DEVICE

An optical element includes a first optical waveguide that extends from a first end portion toward a second end portion, and has a first active layer, a second optical waveguide that has a second active layer, and is disposed side by side with the first optical waveguide and extends from the first end portion toward the second end portion, a reflective film disposed on an end face of the first optical waveguide at a side of the first end portion, and an anti-reflection film disposed on an end face of the second optical waveguide at the side of the first end portion, wherein the anti-reflection film extends from a side of the second optical waveguide to the first optical waveguide at the first end portion, and the reflective film includes the anti-reflection film as one of constituent elements. 1. An optical element comprising:a first optical waveguide that extends from a first end portion toward a second end portion, and has a first active layer;a second optical waveguide that has a second active layer, and is disposed side by side with the first optical waveguide and extends from the first end portion toward the second end portion;a reflective film disposed on an end face of the first optical waveguide at a side of the first end portion; andan anti-reflection film disposed on an end face of the second optical waveguide at the side of the first end portion,wherein the anti-reflection film extends from a side of the second optical waveguide to the first optical waveguide at the first end portion, and the reflective film includes the anti-reflection film as one of constituent elements.2. The optical element according to claim 1 , wherein the anti-reflection film is made of a dielectric material claim 1 , andthe reflective film is formed by laminating the anti-reflection film, and another dielectric material different from the dielectric material or a metal film.3. The optical element according to claim 1 , wherein a plurality of first optical waveguides is provided.4. ...

Method of evaluating initial parameters and target values for feedback control loop of wavelength tunable system

A method of determining initial parameters and target values for tuning an emission wavelength of a wavelength tunable laser capable of emitting laser light in a substantial wavelength range is disclosed. The method iterates an evaluation of initial parameters and target values at target wavelengths in a preset order. The evaluation includes steps of supplying empirically obtained parameters to the t-LD, confirming whether the t-LD generates an optical beams, determining the initial parameters and the target values by carrying out feedback loops of the AFC and the APC when the t-LD generates the optical beam, or shifting the wavelength range so as to exclude the current target wavelength when the t-LD generates no optical beam.

Highly Stable Semiconductor Lasers and Sensors for III-V and Silicon Photonic Integrated Circuits

Building blocks are provided for on-chip chemical sensors and other highly-compact photonic integrated circuits combining interband or quantum cascade lasers and detectors with passive waveguides and other components integrated on a III-V or silicon. A MWIR or LWIR laser source is evanescently coupled into a passive extended or resonant-cavity waveguide that provides evanescent coupling to a sample gas (or liquid) for spectroscopic chemical sensing. In the case of an ICL, the uppermost layer of this passive waveguide has a relatively high index of refraction that enables it to form the core of the waveguide, while the ambient air, consisting of the sample gas, functions as the top cladding layer. A fraction of the propagating light beam is absorbed by the sample gas if it contains a chemical species having a fingerprint absorption feature within the spectral linewidth of the laser emission. 1.A highly stable semiconductor laser , comprising:a laser cavity comprising a narrow-ridge waveguide and having a first highly reflective end thereof and a second highly reflective end thereof, the reflectivity of the first and second ends thereof being configured to prevent light emitted from the laser cavity from being fed back into the laser cavity as a result of interactions with external optical elements; anda passive waveguide that runs parallel to the narrow ridge of the laser cavity over a predefined portion of the laser cavity so as to allow the passive waveguide to controllably receive a predetermined fraction of the light emitted from the laser cavity;wherein the predetermined fraction of light from the laser is evanescently coupled to the passive waveguide for output from the highly stable laser.21. The highly stable semiconductor laser according to claim , wherein the first and second ends of the laser cavity comprise a first end facet which is coated for high reflection at the first end thereof and a second end facet which is coated for high reflection at the ...

OPTICAL MODULE

An optical module includes an LD that emits laser beam; a carrier that mounts the LD and thermistor thereon; a photodetector detecting the laser beam output from the LD; a TEC that mounts the carrier and the photodetector thereon; a chassis having a box-shape demarcated by walls that form a space for enclosing the LD, the TEC, and the photodetector therein, wherein at least of the walls has a window, and the thermistor arranged between the LD and the photodetector. 1. An optical module , comprising:an LD that emits laser beam;a carrier that mounts the LD and thermistor thereon;a photodetector detecting the laser beam output from the LD;a TEC that mounts the carrier and the photodetector thereon;a chassis having a box-shape demarcated by walls that form a space for enclosing the LD, the TEC, and the photodetector therein,wherein at least of the walls has a window, and the thermistor arranged between the LD and the photodetector.2. The optical module ofwherein the photodetector composed of a material including a silicon3. The optical module offurther comprising a beam splitter input the laser beam, and output a first output beam and a second output beam opposite to the first output beam.4. The optical module offurther comprising an isolator arranged between the LD and the beam splitter.5. The optical module ofwherein the photodetector includes a 90-degree hybrid, a first light receiving element, a second light receiving element, a third light receiving element.6. The optical module ofwherein the LD being a wavelength tunable laser.7. The optical module ofwherein the wavelength tunable laser includes a Sampled Grating Distributed FeedBack, a Chirped Sampled Grating Distributed Bragg Reflector, and a Semiconductor Optical Amplifier.8. The optical module ofwherein at least of the Sampled Grating Distributed FeedBack and the Chirped Sampled Orating Distributed Bragg Reflector being a heater. The present disclosure relates to an optical module.Japanese Unexamined Patent ...

Bulk direct gap mos2 by plasma induced layer decoupling

Bulk direct transition metal dichalcogenide (TMDC) may have an increased interlayer separation of at least 0.5, 1, or 3 angstroms more than its bulk value. The TMDC may be a bulk direct band gap molybdenum disulfide (MoS2) or a bulk direct band gap tungsten diselenide (WSe 2 ). Oxygen may be between the interlayers. A device may include the TMDC, such as an optoelectronic device, such as an LED, solid state laser, a photodetector, a solar cell, a FET, a thermoelectric generator, or a thermoelectric cooler. A method of making bulk direct transition metal dichalcogenide (TMDC) with increased interlayer separation may include exposing bulk direct TMDC to a remote (aka downstream) oxygen plasma. The plasma exposure may cause an increase in the photoluminescence efficiency of the TMDC, more charge neutral doping, or longer photo-excited carrier lifetimes, as compared to the TMDC without the plasma exposure.

Semiconductor laser oscillator

A semiconductor laser oscillator includes laser diode modules. A temperature sensor directly or indirectly detects a temperature of at least one of the laser diode modules. A collimating lens collimates respective lasers emitted from the laser diode modules. A grating performs spectrum beam coupling for the lasers emitted from the collimating lens. An incident angle varying mechanism changes incident angles of the respective lasers, at which the lasers emitted from the collimating lens are incident onto the grating in response to the temperature detected by the temperature sensor.

Wavelength tunable laser device and laser module

A wavelength tunable laser device includes: a laser cavity formed of a grating and a reflecting mirror including a ring resonator filter; a gain portion; and a phase adjusting portion. The grating creates a first comb-shaped reflection spectrum. The ring resonator filter includes a ring-shaped waveguide and two arms and creates a second comb-shaped reflection spectrum having peaks of a narrower full width than peaks in the first comb-shaped reflection spectrum at a wavelength interval different from that of the first comb-shaped reflection spectrum. One of the peaks in the first comb-shaped reflection spectrum and one of the peaks in the second comb-shaped reflection spectrum are overlapped on a wavelength axis, and a spacing between cavity modes is narrower than the full width at half maximum of the peaks in the first comb-shaped reflection spectrum.

IMPROVEMENTS IN OR RELATING TO A DISTRIBUTED FEEDBACK LASER DEVICE FOR PHOTONICS INTEGRATED CIRTUIT AND A METHOD OF MANUFACTURE

A distributed feedback laser integrated on silicon comprising a combination of a waveguide of a first material and a laser diode a second material, different from the first material, wherein the laser diode comprises a plurality of regularly spaced metalized grating elements which form a single longitudinal mode; wherein the waveguide comprises a plurality of waveguide elements separated by metalized regions; and wherein the metalized grating elements and the metalized regions are adapted to be coupled to one another to form the distributed feedback laser. 1. A distributed feedback laser integrated on silicon comprising a combination of a waveguide of a first material and a laser diode a second material , different from the first material , wherein the laser diode comprises a plurality of regularly spaced metalized grating elements which form a single longitudinal mode; wherein the waveguide comprises a plurality of waveguide elements separated by metalized regions; andwherein the metalized grating elements and the metalized regions are adapted to be coupled to one another to form the distributed feedback laser.2. The distributed feedback laser according to claim 1 , wherein the first material is silicon and the second material comprises a III-V material.3. The distributed feedback laser according to or claim 1 , wherein the metalized grating elements and the metalized regions are adapted to be bonded to one another to form an internal bonded metal layer.4. The distributed feedback laser according to claim 3 , wherein bonding comprises butt coupling.5. The distributed feedback laser according to or claim 3 , wherein the bonding is achieved by applying force to the push together the waveguide and laser diode in an atmosphere of nitrogen at a predetermined temperature for a predetermined time.6. The distributed feedback laser according to claim 5 , wherein the force is between about 0.5 and 3 N.7. The distributed feedback laser according to or claim 5 , wherein the ...

TUNABLE LASER AND MANUFACTURING METHOD FOR TUNABLE LASER

A wavelength tunable laser includes: a heating layer, a dielectric layer, reflectors, a transport layer, a support layer, and a substrate layer. The heating layer is located above the transport layer; the transport layer is located above the support layer, and the transport layer includes an upper cladding layer, a waveguide layer, and a lower cladding layer from top to bottom; the reflector is located in the transport layer; the support layer has a protection structure, where the protection structure forms a hollow structure together with the transport layer and the substrate layer, and the hollow structure has a support structure; and the substrate layer is located below the support layer. The heating layer, the reflector, and a part of the transport layer form a suspended structure to prevent heat dissipation. Thus thermal tuning efficiency can be improved, and power consumption can be lowered. 1. A wavelength tunable laser , comprising:a substrate layer;a support layer disposed above the substrate layer and having a protection structure;a transport layer disposed above the support layer and comprising a lower cladding layer, a waveguide layer and an upper cladding layer, wherein the protection structure forms a hollow structure together with the transport layer and the substrate layer, and the hollow structure includes a support structure;a heating layer disposed above the transport layer; anda reflector disposed in the transport layer.2. The laser according to claim 1 , further comprising:in a first direction, a gap between the support structure and the protection structure, wherein the first direction is a transmission direction of light in the waveguide layer.3. The laser according to claim 1 , further comprising:in a second direction, a gap between the support structure and the protection structure, wherein the second direction is perpendicular to the transmission direction of light in the waveguide layer.4. The laser according to claim 1 , wherein the ...

Method to determine operating conditions of wavelength tunable laser diode and to control optical transmitter providing wavelength tunable laser diode

A method to control a wavelength tunable laser diode (tunable LD) is disclosed. The tunable LD includes a SG-DFB region and a CSG-DBR region to tune the emission wavelength thereof. The CSG-DBR region includes three segments, where the refractive indices of respective segments are variable by heaters provided therein. When the electrical power supplied to two segments is optionally selected, the power supplied to the rest segment is corrected by an offset from a value reflecting physical dimensions of the heaters. The offset is determined such that the tunable LD shows the best side mode suppression ratio (SMSR).

TUNABLE EMITTING DEVICE WITH A DIRECTLY MODULATED LASER COUPLED TO A RING RESONATOR

An emitting device () is intended for delivering photons with a chosen wavelength. This emitting device () comprises an InP substrate () with a directly modulated laser () arranged for generating photons modulated by a non-return-to-zero modulation to produce data to be transmitted, a passive ring resonator () monolithically integrated with the directly modulated laser () and having a resonance amongst several ones that is used for filtering a zero level induced by the data modulation, and a tuning means () arranged along the directly modulated laser () and/or around the ring resonator () to tune the photon wavelength and/or the ring resonator resonance used for filtering. 1. Emitting device for delivering photons with a chosen wavelength , said emitting device comprising:i) an InP substrate with a directly modulated laser arranged for generating photons modulated by a non-return-to-zero modulation to produce data to be transmitted, the active structure of the directly modulated laser being epitaxially grown on the InP substrate,ii) a passive ring resonator being defined in a passive section of the InP substrate, said passive ring resonator being monolithically integrated with said directly modulated laser by carrying out a p-doped re-growth both in the active and passive sections of the InP substrate followed by a hydrogenation of the passive section of the InP substrate for rendering the p-doping of the re-growth inactive, said passive ring resonator having a resonance amongst several ones that is used for filtering a zero level induced by said data modulation, andiii) a tuning means arranged along said directly modulated laser and/or around said ring resonator to tune the photon wavelength and/or said ring resonator resonance used for filtering.2. Emitting device according to claim 1 , wherein said ring resonator is butt-joined to said directly modulated laser to reduce insertion losses.3. Emitting device according to one of claim 1 , wherein said tuning means ...

TEMPERATURE CONTROL CIRCUIT, TRANSMITTER, AND TEMPERATURE CONTROL METHOD

A temperature control circuit includes a temperature detector to detect temperature of an LD, a TEC to control temperature of the LD, a current calculation circuit to calculate an amount of current caused to flow through the TEC on the basis of a temperature of the LD and a target temperature, a current control circuit to control current to flow through the TEC on the basis of the amount of current, and a target temperature calculation circuit to set a first target temperature as the target temperature during LD shutdown cancellation, to set the target temperature to monotonously decrease from the first target temperature to a second target temperature lower than the first target temperature until a certain time elapses since an LD shutdown start, and to set the second target temperature as the target temperature when the certain time elapses since the LD shutdown start. 1: A temperature control circuit comprising:a temperature detector to detect temperature of a laser diode;a thermoelectric element to control temperature of the laser diode by performing heat absorption and radiation in accordance with an amount of current flowing therethrough;a current calculation circuit to calculate an amount of current caused to flow through the thermoelectric element on a basis of a temperature of the laser diode detected by the temperature detector and a target temperature;a current control circuit to control a current caused to flow through the thermoelectric element on a basis of an amount of current calculated by the current calculation circuit; anda target temperature calculation circuit to set a first target temperature as the target temperature, during a time period in which the light emission stop state of the laser diode is cancelled on a basis of a light emission stop signal that indicates whether to cause the laser diode to be in a light emission stop state, to set the target temperature so as to monotonously decrease from the first target temperature to a second ...

LIGHT EMITTING MODULE INCLUDING ENHANCED EYE-SAFETY FEATURE

Illuminator modules having improved safety features are described. In some implementations, light to be emitted from a module is produced by a light source, and light reflected by an optical component disposed over the light source is detected by a photodetectors. A distribution of the reflected light detected by the photodetectors is monitored, and an optical output power of the light source is regulated if it is determined, based on the monitored distribution of light, that an unsafe level of light may be emitted from the module.

Semiconductor laser element

A semiconductor laser element includes a semiconductor laminated structure that has a substrate, an n type cladding layer disposed at a front surface side of the substrate, an active layer disposed at an opposite side of the n type cladding layer to the substrate, and p type cladding layers disposed at an opposite side of the active layer to the n type cladding layer. The active layer includes a quantum well layer having a tensile strain for generating TM mode oscillation and the n type cladding layer and the p type cladding layers are respectively constituted of AlGaAs layers.

Integrated wavelength locker

Described are various configurations of integrated wavelength lockers including asymmetric Mach-Zehnder interferometers (AMZIs) and associated detectors. Various embodiments provide improved wavelength-locking accuracy by using an active tuning element in the AMZI to achieve an operational position with high locking sensitivity, a coherent receiver to reduce the frequency-dependence of the locking sensitivity, and/or a temperature sensor and/or strain gauge to computationally correct for the effect of temperature or strain changes.

Semiconductor laser apparatus

According to the present invention, in a time wavelength division multiplexing-passive optical network (TWDM-PON) such as the next generation passive optical network 2 (NG-PON2) requiring a burst mode operation, in a process of manufacturing a semiconductor laser requiring selection of a very narrow wavelength, two laser waveguides having different oscillation wavelengths are formed in one laser diode chip, thereby making it possible to improve a wavelength yield of the chip. In addition, when any one laser waveguide participates in communication, a current applied to a waveguide laser that does not participate in the communication is modulated and applied to the waveguide laser, with respect to a wavelength change generated by a change in a current applied to a burst mode operation waveguide laser participating in the communication, to stabilize a wavelength of laser light oscillated from the laser waveguide participating in the communication, thereby enabling burst mode communication at a dense wavelength division multiplexing (DWDM) level.

ULTRA-LOW NOISE, HIGHLY STABLE SINGLE-MODE OPERATION, HIGH POWER, BRAGG GRATING BASED SEMICONDUCTOR LASER

A laser including: a gain chip; an external cavity incorporating a Bragg grating; and a baseplate; wherein a first end of the gain chip has a high reflectivity facet forming a first end of the laser cavity; a second end of the gain chip has a low reflectivity facet; and a second part of the external cavity comprises a Bragg grating, supported by the baseplate, the temperature of the baseplate being maintained through a feedback loop; wherein the optical length of the external cavity is at least an order of magnitude greater than the optical length of the gain chip; wherein the Bragg grating is physically long and occupies a majority of the length of the external cavity and is apodized to control the sidemodes of the grating reflection. 1. A laser comprising:a semiconductor gain chip;an external cavity; anda first thermally conductive baseplate;wherein a first end of the gain chip has a high reflectivity facet forming a first end of the laser cavity; a second end of the gain chip has a low reflectivity facet, allowing light generated from the gain chip to be coupled with a first end of the external cavity;and a second part of the external cavity comprises a Bragg grating forming a second end of the laser cavity;wherein the external cavity comprising the Bragg grating is supported by the first thermally conductive baseplate;wherein the optical length of the external cavity is at least an order of magnitude greater than the optical length of the gain chip;wherein the physical length of the Bragg grating is greater than 20 mm and occupies at least 75% of the physical length of the external cavity; andwherein the Bragg grating is apodized to control the sidemodes of the grating reflection.2. The laser of claim 1 , wherein the external cavity comprises an optical fiber.3. The laser of claim 2 , wherein the Bragg grating is a fiber Bragg grating (FBG) within the optical fiber.4. The laser of claim 1 , wherein the external cavity comprises a waveguide.5. The laser of claim ...

LASER CONTROL

The description relates to laser control. One example can include a laser that has a laser emitter configured to generate a laser beam for intervals of time (e.g., pixel times). The laser can have a compensation and control component configured to receive a predicted laser emitter temperature of the laser emitter, obtain a desired optical power for an interval, and compute a compensated electrical current for the interval utilizing multiple light to current look up tables. Individual light to current look up tables can relate to specific laser emitter temperatures. 1. A system , comprising:a laser that comprises a laser emitter configured to generate a laser beam;a sensor configured to sense a temperature of a case of the laser;a laser emitter temperature prediction model that can model thermal impedance of the laser from the laser emitter to the case to predict laser emitter temperature from the sensed temperature of the case of the laser; and,a compensation and control component configured to receive a desired optical power and to compute a compensated electrical current to drive the laser based upon the predicted laser emitter temperature, the compensated electrical current computed for the predicted laser emitter temperature to cause the laser emitter to generate the laser beam having an actual optical power that matches the desired optical power.23-. (canceled)4. The system of claim 1 , wherein the thermal impedance reflects elements that have a thermal relationship with the laser emitter.5. The system of claim 4 , wherein the elements include another laser emitter.6. The system of claim 1 , wherein the laser emitter temperature prediction model can model thermal characteristics and internal temperature of the laser over time.7. The system of claim 6 , wherein the laser emitter temperature prediction model can model a particular point on the laser as a function of time and power.8. The system of claim 7 , wherein the laser emitter temperature prediction model ...

Packaging structure and method of packaging tunable laser device, and tunable laser device

The present disclosure provides a packaging structure and a method of packaging an tunable laser device, and an tunable laser device. The packaging structure of the tunable laser device may include a TO tube base and a TO tube cap, wherein a first thermal sink is disposed on the TO tube base, a semiconductor laser chip is disposed on a vertical side of the first thermal sink, an aspheric lens is disposed on the TO tube cap, and the semiconductor laser chip is disposed on a central axis of the aspheric lens; and wherein the vertical side of the first thermal sink is a side of the first thermal sink perpendicular to the TO tube base. The tunable laser device according to the present disclosure may be applicable to communication over an optical fiber.

Optical Amplifier and Optical Transmission System

An optical amplifying apparatus that amplifies an optical signal, including an input section whereto the optical signal is inputted, a laser light source that generates laser light, the laser light source including an uncooled semiconductor laser device, an optical fiber that amplifies the optical signal by a stimulated emission based on the laser light from the laser light source, an output section that outputs the optical signal amplified by the optical fiber, and a passive optical component disposed between the optical fiber and the output section. The laser light source is thermally coupled to the optical fiber and/or the passive optical component via a thermally conductive medium. An oscillating wavelength of the laser light source is varied by increasing a temperature of the laser light source with heat generated by the optical fiber and/or the passive optical component. 1. An optical amplifying apparatus that amplifies an optical signal , comprising:an input section whereto the optical signal is inputted;a laser light source that generates multimode laser light propagating in a multimode, the laser light source including a multimode semiconductor laser device with no electronic cooling element;a double-clad optical fiber that amplifies the optical signal by a stimulated emission based on the multimode laser light from the laser light source;an output section that outputs the optical signal amplified by the double-clad optical fiber;a passive optical component disposed between the double-clad optical fiber and the output section; anda thermally conductive medium,the double-clad optical fiber being mounted on the thermally conductive medium, the double-clad optical fiber being configured to heat the thermally conductive medium by propagation of the multimode laser light,the laser light source being mounted on the thermally conductive medium so as to be heated by the double-clad optical fiber via the thermally conductive medium,an oscillating wavelength of the ...

Light-emitting element module, atomic oscillator, and electronic apparatus

A light-emitting element module includes: a Peltier device that includes a first substrate, and a second substrate causing a temperature difference from the first substrate, and a power terminal disposed on the first substrate; a light-emitting element that is disposed on a side of the second substrate of the Peltier device and of which temperature is adjusted by the Peltier device; a temperature sensor that is disposed on the side of the second substrate of the Peltier device; a package that includes a base and a lid; a first external electrode that is electrically connected to the power terminal; a second external electrode that is electrically connected to the temperature sensor; and a third external electrode that is electrically connected to the light-emitting element. The third external electrode is disposed between the first and second external electrodes.

Light-emitting element module, atomic oscillator, and electronic apparatus

A light-emitting element module includes a light-emitting element that emits light, a base that has a depression portion in which the light-emitting element is accommodated, and a lid that covers an opening of the depression portion and is joined to the base. The lid includes a protrusion portion that protrudes on an opposite side to the base and has a hole through which the light passes and a window that is installed in the protrusion portion to block the hole and transmits the light. A surface of the window on a side of the light-emitting element is inclined with respect to a surface perpendicular to an optical axis of the light.

SMALL FORM FACTOR TRANSMITTING DEVICE

A packaged transmitter device includes a base member comprising a planar part mounted with a thermoelectric cooler, a transmitter, and a coupling lens assembly, and an assembling part connected to one side of the planar part. The device further includes a circuit board bended to have a first end region and a second end region being raised to a higher level. The first end region disposed on a top surface of the planar part includes multiple electrical connection patches respectively connected to the thermoelectric and the transmitter. The second end region includes an electrical port for external connection. Additionally, the device includes a cover member disposed over the planar part. Furthermore, the device includes a cylindrical member installed to the assembling part for enclosing an isolator aligned to the coupling lens assembly along its axis and connected to a fiber to couple optical signal from the transmitter to the fiber. 1. A method of implementing a photonic transceiver in a network system comprising:packaging a photonic transceiver in a case with two transmitter devices mounted side-by-side on a PCB board and respectively coupled to a silicon photonics chip, the case comprising a first opening at a front end of the PCB board for mounting an optical input port and an optical output port respectively connected to the silicon photonics chip via optical fibers, and a second opening at a back end for the PCB board with multiple metallic stripes formed thereof as an electrical connector;plugging the electrical connector to an electrical node of a communication network; andconnecting a pair of external optical fibers respectively to the optical input port and the optical output port, the pair of external optical fibers being connected respectively to an input path for providing incoming optical signals and output path for transmitting optical signals in the communication network.2. The method of wherein packaging the photonic transceiver comprises:providing a ...

Thermal Compensation for Burst-Mode Laser Wavelength Drift

An apparatus comprising a laser comprising an active layer and configured to emit an optical signal, wherein a temperature change of the laser causes the optical signal to shift in wavelength, and a heater thermally coupled to the active layer and configured to reduce a wavelength shift of the optical signal by applying heat to the active layer. 1. An apparatus comprising:a laser configured to emit an optical signal during a burst period;a heater thermally coupled to the laser and configured to apply heat the laser; anda driver of an electric current for generating the heat,wherein the electric current is at a first level during a first period before a start of the burst period and at a second level during a second period after the start,wherein the first level is greater than the second level, andwherein the heat is applied to the laser before the start of the burst period to substantially stabilize a temperature of the laser during the burst period.2. The apparatus of claim 1 , wherein the electric current is dedicated to the heater.3. The apparatus of claim 1 , wherein a duration of the heater applying the heat is about 125 microseconds (μs) claim 1 , wherein the temperature varies no more than about 0.2 degrees Celsius (° C.) when the heater applies the heat claim 1 , and wherein the wavelength shift is no more than about 0.02 nanometers (nm) when the heater applies the heat.4. The apparatus of claim 1 , further comprising a driving circuit coupled to the heater and comprising a constant current source configured to generate the electric current.5. The apparatus of claim 4 , wherein the constant current source comprises:a transistor comprising a base; anda diode coupled to the base, andwherein the transistor and the diode have similar voltage-temperature characteristics such that the transistor and the diode are configured to create a constant voltage difference that is substantially independent of an ambient temperature of the driving circuit.6. The apparatus ...

SEMICONDUCTOR LASER EXCITED SOLID STATE LASER DEVICE AND LASER LIGHT OUTPUT METHOD

A semiconductor laser excited solid state laser device and method. The device including a semiconductor laser; a driving device; a solid state laser module which has maximum output efficiency at the set temperature and which generates, from excitation light, an output light of a predetermined output level when the optical noise is at or below a fixed level and the output level of the excitation light is the set output level; a single temperature adjustment device which adjusts the temperature of the semiconductor laser and the temperature of the solid state laser module; and a control device which controls the driving device such that the output light will be at the predetermined output level and controls the temperature adjustment device such that the temperature of the semiconductor laser and the solid state laser module will be the set temperature. 1. A semiconductor laser excited solid state laser device , comprising:a semiconductor laser which outputs a single transverse mode excitation light of fixed wavelength at a set output level, without undergoing mode hopping, at a set temperature;a driving device which drives said semiconductor laser;a solid state laser module which has maximum output efficiency at said set temperature and which generates, from said excitation light, an output light of a predetermined output level when the optical noise is at or below a fixed level and the output level of said excitation light is said set output level;a single temperature adjustment device which adjusts the temperature of said semiconductor laser and the temperature of said solid state laser module; anda control device which controls said driving device such that said output light will be at said predetermined output level and controls said temperature adjustment device such that the temperature of said semiconductor laser and said solid state laser module will be said set temperature.2. The semiconductor laser excited solid state laser device described in claim 1 , ...

LASER LIGHT SOURCE APPARATUS, AND METHOD FOR CONTROLLING TEMPERATURE OF WAVELENGTH CONVERSION ELEMENT IN LASER LIGHT SOURCE APPARATUS

The wavelength of fundamental wave light emitted from a semiconductor laser is converted by a wavelength conversion element, and the wavelength-converted light is emitted. A power supply circuit feeds electric power to the semiconductor laser. A control part controls an amount of electric power to be fed to a heater such that the wavelength conversion element becomes a temperature that optimizes the wavelength conversion efficiency. Temperatures detected by an element temperature detector and a light source part temperature detector are introduced to the control part, and the control part takes a wavelength conversion element temperature, at which a temperature detected by the light source part temperature detector is minimum, as a set temperature that makes the wavelength conversion efficiency optimal, and feedback-controls the wavelength conversion element temperature such that the wavelength conversion element temperature is at the set temperature by controlling the heating quantity of the heater. 1. A laser light source apparatus comprising:a light source part having a semiconductor laser, a wavelength conversion element configured to convert a wavelength of a laser beam emitted from the semiconductor laser, and an external resonator configured to select that laser beam which has a prescribed wavelength from the laser beam released from the wavelength conversion element and reflect the selected laser beam toward the semiconductor laser;a power supply circuit configured to feed electric power to the semiconductor laser;an element temperature detecting unit configured to detect temperature of the wavelength conversion element;a heating unit configured to heat the wavelength conversion element;a control part configured to control the power supply circuit and the heating unit; anda light source part temperature detecting unit configured to detect temperature of the light source part,the control part having:a temperature controller configured to control an amount of ...

Method of manufacturing frequency tunable terahertz transceiver

A method of manufacturing a frequency tunable terahertz transceiver including two separate distributed feedback lasers manufactured in one substrate, includes forming a lower clad layer on the substrate, forming an active layer on the lower clad layer, forming an upper clad layer on the active layer. And interposing first and second diffraction grating layers between the upper clad layers. A diffraction grating is manufactured by etching the first and second diffraction grating layers. The active layer is integrated into a passive waveguide. An electrode is formed on the upper clad layer.

TUNABLE LASER WITH DIRECTIONAL COUPLER

A tunable laser has a first mirror, a second mirror, a gain medium, and a directional coupler. The first mirror and the second mirror form an optical resonator. The gain medium and the directional coupler are, at least partially, in an optical path of the optical resonator. The first mirror and the second mirror comprise binary super gratings. Both the first mirror and the second mirror have high reflectivity. The directional coupler provides an output coupler for the tunable laser. 1. (canceled)2. A device for a laser comprising:a first mirror having a first plurality of reflectance peaks;a second mirror having a second plurality of reflectance peaks, wherein the first mirror and the second mirror are configured to form a resonator;a gain medium within the resonator; anda coupler between the first mirror and the second mirror, the coupler configured to guide a selected percentage of light directly, not evanescently, out of the resonator through a port of the coupler, such that the selected percentage of light coupled out of the resonator is independent of spectral properties of the first mirror and the second mirror, and wherein the coupler is a waveguide coupler.3. The device of claim 2 , wherein:wherein a maximum reflectance of the first plurality of reflectance peaks is greater than 90%; andwherein a maximum reflectance of the second plurality of reflectance peaks is greater than 90%.4. The device of claim 2 , wherein:the coupler comprises a ridge portion having a width at a waist of the coupler, wherein the waist is at a center of the coupler; andthe selected percentage of light guided out of the resonator through the port of the coupler is based on the width of the ridge portion at the waist of the coupler.5. The device of claim 2 , wherein:the coupler comprises a first ridge and a second ridge;a gap separates the first ridge from the second ridge; andthe gap is equal to or greater than 0.75 microns.6. The device of claim 2 , wherein the first mirror claim 2 , ...

REFLECTOR STRUCTURE FOR TUNABLE LASER AND TUNABLE LASER

A reflector structure for a tunable laser and a tunable laser. A super structure grating is used as a reflector structure, and a suspended structure is formed around a region in which the super structure grating is located, to implement, using the suspended structure, thermal isolation around the region in which the super structure grating is located, and increase thermal resistance, such that less heat is lost, and heat is concentrated in the region in which the super structure grating is located, thereby improving thermal tuning efficiency of the reflector structure. Moreover, lateral support structures are disposed on two sides of the suspended structure, to provide a mechanical support for the suspended structure. In addition, regions in the super structure grating that correspond to any two lateral support structures on a same side of the suspended structure fall at different locations in a spatial period of the super structure grating. 1. A reflector structure for a tunable laser , comprising:a substrate layer, a support layer, a lower cladding layer, a waveguide layer, an upper cladding layer, and a heating layer that are stacked in sequence from bottom to top, whereinthe reflector structure further comprises a super structure grating, the super structure grating is disposed between the upper cladding layer and the lower cladding layer along a propagation direction of light in the waveguide layer, and the heating layer is located in a region that is on an upper surface of the upper cladding layer opposite from the super structure grating and that is right opposite the super structure grating;the support layer comprises a first support sublayer and a second support sublayer, the first support sublayer and the second support sublayer are located respectively on two sides of an upper surface of the substrate layer along the propagation direction of light in the waveguide layer, and a space extending along the propagation direction of light in the waveguide layer ...

SMALL FORM FACTOR TRANSMITTING DEVICE

A packaged transmitter device includes a base member comprising a planar part mounted with a thermoelectric cooler, a transmitter, and a coupling lens assembly, and an assembling part connected to one side of the planar part. The device further includes a circuit board bended to have a first end region and a second end region being raised to a higher level. The first end region disposed on a top surface of the planar part includes multiple electrical connection patches respectively connected to the thermoelectric and the transmitter. The second end region includes an electrical port for external connection. Additionally, the device includes a cover member disposed over the planar part. Furthermore, the device includes a cylindrical member installed to the assembling part for enclosing an isolator aligned to the coupling lens assembly along its axis and connected to a fiber to couple optical signal from the transmitter to the fiber. 1. A method of implementing a photonic transceiver in a network system comprising:packaging a first transmitter device and a second transmitter device separately in a TEC-TOSA package;coupling the first transmitter device and a second transmitter device respectively to a silicon photonics chip and mounting two TEC-TOSA packages respectively for the first transmitter device and a second transmitter device side-by-side on a PCB board, the PCB board being configured with a front end for mounting an optical input port and an optical output port respectively connected to the silicon photonics chip via optical fibers and a back end for forming multiple metallic stripes configured as an electrical connector;plugging the electrical connector to the network system; andconnecting a pair of external optical fibers respectively to the optical input port and the optical output port for respectively providing incoming optical signals and outgoing optical signals.2. The method of wherein packaging the first transmitter device comprises:providing a base ...

Independent control of emission wavelength and output power of a semiconductor laser

Methods for driving a tunable laser with integrated tuning elements are disclosed. The methods can include modulating the tuning current and laser injection current such that the laser emission wavelength and output power are independently controllable. In some examples, the tuning current and laser injection current are modulated simultaneously and a wider tuning range can result. In some examples, one or both of these currents is sinusoidally modulated. In some examples, a constant output power can be achieved while tuning the emission wavelength. In some examples, the output power and tuning can follow a linear relationship. In some examples, injection current and tuning element drive waveforms necessary to achieve targeted output power and tuning waveforms can be achieved through optimization based on goodness of fit values between the targeted and actual output power and tuning waveforms.

HEAT ASSISTED MEDIA RECORDING DEVICE WITH REDUCED LIKELIHOOD OF LASER MODE HOPPING

An apparatus includes a laser diode, a heater arrangement, and a circuit. The laser diode is configured to facilitate heat assisted magnetic recording during a lasing state. The heater arrangement is positioned proximate the laser diode. The circuit electrically couples the laser diode and the heater arrangement in a parallel relationship. The circuit is configured to alternately operate the laser diode in a lasing state and a non-lasing state, and to activate the heater arrangement during the non-lasing state to warm a junction of the laser diode. 1. An apparatus , comprising:a laser diode configured to facilitate heat assisted magnetic recording during a lasing state;a heater arrangement proximate the laser diode; anda circuit electrically coupling the laser diode and the heater arrangement in a parallel relationship, the circuit configured to alternately operate the laser diode in the lasing state and a non-lasing state, and to activate the heater arrangement during the non-lasing state to warm a junction of the laser diode.2. The apparatus of claim 1 , wherein the heater arrangement comprises a temperature sensor configured to measure a temperature of the junction of the laser diode in one or both of the lasing state and the non-lasing state.3. The apparatus of claim 2 , further comprising:an analyzer configured to determine a temperature at a junction of a laser diode when the laser diode is operated in the lasing state, wherein the analyzer compares the junction temperature and an injection current supplied during the lasing state to stored combinations of junction temperature and injection current to determine a likelihood of mode hopping occurring for the laser diode during the lasing state; anda controller in communication with the analyzer and configured to vary a current supplied to the heater arrangement for varying a temperature of the junction to reduce the likelihood of mode hopping occurring during the lasing state.4. The apparatus of claim 1 , ...

THERMAL MANAGEMENT OF LASER DIODE MODE HOPPING FOR HEAT ASSISTED MEDIA RECORDING

A method and apparatus provide for determining a temperature at a junction of a laser diode when the laser diode is operated in a lasing state that facilitates heat-assisted magnetic recording, comparing the junction temperature and an injection current supplied during the lasing state to stored combinations of junction temperature and injection current, and determining a likelihood of mode hopping occurring for the laser diode during the lasing state based on the comparison to stored combinations of junction temperature and injection current. 1. A method , comprising:determining a temperature at a junction of a laser diode when the laser diode is operated in a lasing state that facilitates heat-assisted magnetic recording;comparing the junction temperature and an injection current supplied to the laser diode during the lasing state to stored combinations of junction temperature and injection current;determining a likelihood of mode hopping occurring for the laser diode during the lasing state based on the comparison to stored combinations of junction temperature and injection current; and measuring a temperature of the junction of the laser diode when in the lasing state and in the non-lasing state; and', 'applying a drive signal to a heating arrangement coupled in a parallel relationship with the laser diode, wherein the heating arrangement comprises at least a diode configured to be reverse biased during the lasing state and forward biased during the non-lasing state., 'heating the laser diode during the non-lasing state, wherein heating the laser diode comprises2. The method of claim 1 , wherein the step of determining the temperature at the junction comprises:determining a voltage differential between a non-steady lasing state of the laser diode and a steady state lasing state of the laser diode; andcalculating the temperature based on the voltage differential.34-. (canceled)5. The method of claim 1 , further comprising heating the laser diode during at least a ...

Photoacoustic Apparatus and Methods

A photoacoustic apparatus including circuitry configured to generate a frequency comb of light including a plurality of wavelengths; circuitry configured to modulate the light of the frequency comb at a modulation frequency; circuitry configured to change at least a subset of the plurality of wavelengths of the frequency comb of light; and at least one acoustic sensor configured to detect sound produced by analyte illuminated by the frequency comb of light.

SMALL FORM FACTOR TRANSMITTING DEVICE

A packaged transmitter device includes a base member comprising a planar part mounted with a thermoelectric cooler, a transmitter, and a coupling lens assembly, and an assembling part connected to one side of the planar part. The device further includes a circuit board bended to have a first end region and a second end region being raised to a higher level. The first end region disposed on a top surface of the planar part includes multiple electrical connection patches respectively connected to the thermoelectric and the transmitter. The second end region includes an electrical port for external connection. Additionally, the device includes a cover member disposed over the planar part. Furthermore, the device includes a cylindrical member installed to the assembling part for enclosing an isolator aligned to the coupling lens assembly along its axis and connected to a fiber to couple optical signal from the transmitter to the fiber. 1. A packaged transmitter device comprising:a base member comprising a planar part mounted with a thermoelectric cooler module, a transmitter module, and an optical coupling lens, and an assembling part connected to one side of the planar part;a circuit board bended to have a first end region being disposed on a top surface of the planar part and a second end region being raised to a higher level, the first end region comprising multiple electrical connection patches respectively connected to the thermoelectric module and the transmitter module, the second end region comprising an electrical port for external connection;a cover member disposed to a fixed position over the planar part to at least cover the thermoelectric module, the transmitter module, the optical coupling lens, and the first end region of the circuit board; anda cylindrical member installed to the assembling part for enclosing an isolator aligned to the optical coupling lens on the base member and a second lens along its axial line for coupling optical signal from the ...

SMALL FORM FACTOR TRANSMITTING DEVICE

A packaged transmitter device includes a base member comprising a planar part mounted with a thermoelectric cooler, a transmitter, and a coupling lens assembly, and an assembling part connected to one side of the planar part. The device further includes a circuit board bended to have a first end region and a second end region being raised to a higher level. The first end region disposed on a top surface of the planar part includes multiple electrical connection patches respectively connected to the thermoelectric and the transmitter. The second end region includes an electrical port for external connection. Additionally, the device includes a cover member disposed over the planar part. Furthermore, the device includes a cylindrical member installed to the assembling part for enclosing an isolator aligned to the coupling lens assembly along its axis and connected to a fiber to couple optical signal from the transmitter to the fiber. 1. A photonic transceiver packaged in a case with two transmitter devices side-by-side mounted on a PCB board and respectively coupled to a silicon photonics chip , each transmitter device comprising:a base member comprising a planar part mounted with a thermoelectric cooler module, a transmitter module, and an optical coupling lens assembly, and an assembling part connected to one side of the planar part;a circuit board bended to have a first end region being disposed on a top surface of the planar part and a second end region being raised to a higher level, the first end region comprising multiple electrical connection patches respectively connected to the thermoelectric module and the transmitter module, the second end region comprising an electrical port for external connection;a cover member disposed to a fixed position over the planar part to at least cover the thermoelectric module, the transmitter module, the optical coupling lens assembly, and the first end region of the circuit board; anda cylindrical member installed to the ...

DENSELY ARRAYED WAVEGUIDES WITH LOW CROSS-COUPLING

Described herein are lasers comprising an output port to output an optical signal, a plurality of waveguide segments forming an optical cavity length, and a resonant optical cavity comprising the optical cavity length, a gain medium included in the resonant optical cavity to amplify the optical signal, and a heating element disposed near at least two of the plurality of waveguide segments, the heating element controllable to adjust the phase of the optical signal by heating the waveguide segments. Described herein are optical devices comprising a first plurality of ports to output a plurality of optical signals, a second plurality of ports to receive the plurality of optical signals, and a plurality of coupling waveguides. The plurality of waveguide may comprise a pair of adjacent waveguides separated by a first distance, each of the pair of adjacent waveguides comprising a different width. 1. A laser comprising:an output port to output an optical signal;a plurality of waveguide segments forming an optical cavity length; anda resonant optical cavity comprising the optical cavity length;a gain medium included in the resonant optical cavity to amplify the optical signal; anda heating element disposed near at least two of the plurality of waveguide segments, the heating element controllable to adjust the phase of the optical signal by heating the at least two waveguide segments.2. The laser of claim 1 , wherein at least some of the adjacent waveguide segments of the plurality of waveguide segments comprise different widths.3. The laser of claim 1 , wherein the plurality of waveguide segments comprises:a first pair of adjacent waveguide segments comprising different widths and separated by a first distance; anda second pair of adjacent waveguide segments comprising a same width and separated by a second distance greater than the first distance.4. The laser of claim 1 , wherein the plurality of waveguide segments are parallel to each other.5. The laser of claim 4 , ...

Cooling device and semiconductor laser device

There is provided a semiconductor laser device including a plurality of members constituting a first group and a second group in each of which a semiconductor laser element is incorporated, a cooling jacket having, on a surface of the cooling jacket, a first region in which the member of the first group is disposed and a second region in which the member of the second group is disposed, and a cooling medium channel which is disposed in a portion close to the first region and separate from the second region inside the cooling jacket and through which a cooling medium passes.

System and method for controlling collocated multiple wavelength tuned lasers

Systems and methods are disclosed herein for controlling laser beams for a plurality of collocated laser assemblies. The laser beams are optimized by controlling outputs of a primary power source (current for generating a laser beam) and a secondary power source (heating device) for each of the respective laser assemblies. The states of the power supply may be cycled and modulated to provide optimal performance.

Wavelength tunable laser device and method for manufacturing the same

A wavelength tunable laser device includes a substrate including silicon, the substrate having a waveguide, a first semiconductor element bonded to the substrate, the first semiconductor element including an active layer of a group III-V compound semiconductor, and a second semiconductor element bonded to the substrate, the second semiconductor element facing to the first semiconductor element in a direction along which light emitted from the first semiconductor element propagates, the second semiconductor element including a grating formed of a group III-V compound semiconductor. The grating selects a wavelength of light.

LASER LIGHT SOURCE DEVICE

A laser light source device has a light source unit including a semiconductor laser element that emits laser light having a predetermined wavelength band at a temperature from an allowable lower limit temperature to an allowable upper limit temperature, a cooler, an element temperature measurement section, a cooler temperature measurement section, and a controller that controls the cooler. The controller controls the cooler such that the cooler temperature approaches a set temperature. The controller lowers the set temperature as long as the element temperature exceeds the allowable upper limit temperature, and the controller increases the set temperature as long as the element temperature falls below the allowable lower limit temperature. 1. A laser light source device comprising:a light source unit including a semiconductor laser element that emits laser light having a predetermined wavelength band at a temperature from an allowable lower limit temperature to an allowable upper limit temperature;a cooler connected to the light source unit;an element temperature measurement section that measures an element temperature which is a temperature of the semiconductor laser element;a cooler temperature measurement section that measures a cooler temperature which is a temperature of the cooler and is a temperature at a position away from the element temperature; anda controller that controls the cooler,wherein the controller controls the cooler such that the cooler temperature approaches a set temperature,the controller lowers the set temperature as long as the element temperature exceeds the allowable upper limit temperature, andthe controller increases the set temperature as long as the element temperature falls below the allowable lower limit temperature.2. The laser light source device according to claim 1 ,wherein the controller lowers the set temperature as long as the element temperature exceeds the allowable upper limit temperature for a certain time, andthe ...

Integrated wavelength locker

Described are various configurations of integrated wavelength lockers including asymmetric Mach-Zehnder interferometers (AMZIs) and associated detectors. Various embodiments provide improved wavelength-locking accuracy by using an active tuning element in the AMZI to achieve an operational position with high locking sensitivity, a coherent receiver to reduce the frequency-dependence of the locking sensitivity, and/or a temperature sensor and/or strain gauge to computationally correct for the effect of temperature or strain changes.

INTEGRATED WAVELENGTH LOCKER

Described are various configurations of integrated wavelength lockers including asymmetric Mach-Zehnder interferometers (AMZIs) and associated detectors. Various embodiments provide improved wavelength-locking accuracy by using an active tuning element in the AMZI to achieve an operational position with high locking sensitivity, a coherent receiver to reduce the frequency-dependence of the locking sensitivity, and/or a temperature sensor and/or strain gauge to computationally correct for the effect of temperature or strain changes. 1. A wavelength locker comprising:an athermal asymmetric Mach-Zehnder interferometer (AMZI) comprising an input coupler, two waveguide arms, and an output coupler having at least two output ports;placed at the at least two output ports, at least two respective photodetectors for measuring at least two respective optical interference signals exiting the at least two output ports;a temperature sensor to measure a temperature of the AMZI and a strain gauge to measure a strain in the AMZI; andcircuitry configured to adjust a locking condition based on the measured temperature and strain, and to tune a frequency of light coupled into the AMZI, based on a feedback parameter derived from the measured optical interference signals, to satisfy the adjusted locking condition.2. The wavelength locker of claim 1 , wherein the output coupler and the at least two photodetectors are configured as a coherent receiver in which relative phase shifts imparted between two signals being interfered to form the optical interference signals differ between at least two of the output ports by a value that is not a multiple of 180° claim 1 , and wherein the feedback parameter is a filter phase and the locking condition is satisfied if the filter phase matches a target filter phase associated with a specified locking frequency claim 1 , the target filter phase being adjusted based on the measured temperature and strain.3. The wavelength locker of claim 1 , wherein ...

THERMAL-MECHANICAL ADJUSTMENT FOR LASER SYSTEM

Provided is a laser system that includes a laser head having a laser holder configured to house a laser beam and a lens for reflecting the laser beam at a predetermined wavelength, and a thermal-mechanical adjustment device disposed on the laser head and configured to adjust a temperature and an alignment of the laser beam, to maintain the predetermined wavelength of the laser beam. 1. A laser system comprising:a laser head including a laser holder configured to house a laser beam and a lens for reflecting the laser beam at a predetermined wavelength; anda thermal-mechanical adjustment device (i) disposed on the laser head and configured to adjust a temperature and an alignment of the laser beam and (ii) to maintain the predetermined wavelength of the laser beam.2. The laser system of claim 1 , further comprising:a chamfered opening formed at one end of the laser head opposite the emitting end of the laser beam;a pivot bar disposed within the chamfered opening and configured to pivot the laser beam about its circumference at a pivot point and to sway at an angle to the rotation thereof within the chamfered opening.3. The laser system of claim 2 , wherein the angle is approximately 90°.4. The laser system of claim 2 , wherein the thermal-mechanical adjustment device comprises:a plurality of first thermally conductive portions disposed at opposite sides of the laser head adjacent to respective ends of the pivot bar and configured to apply a resistive force to the laser head.5. The laser system of claim 4 , wherein the first thermally conductive portions comprise a thermally conductive foam material.6. The laser system of claim 4 , wherein the thermal-mechanical adjustment device further comprises:a spring device disposed at another end of the laser head opposite the end housing the pivot bar and configured to apply a pulling force to the laser head; anda plurality of second thermally conductive portions disposed adjacent to the spring device and configured to apply a ...

WAVELENGTH-TUNABLE LASER

This application describes a wavelength-tunable laser apparatus, which reduces complexity of wavelength tuning of a laser. The laser includes a reflective gain unit, an optical phase shifter, a coupler, and a passive filter unit array. Furthermore, an output port of the reflective gain unit is connected to an input port of the optical phase shifter, an output port of the optical phase shifter is connected to an input port of the coupler, a first output port of the coupler is connected to an input port of the passive filter unit array, and a second output port of the coupler is an output port of the laser. The passive filter unit array includes a plurality of passive filter units, where any two of the plurality of passive filter units have different wavelength tuning ranges, and each filter unit has a linearly tunable wavelength. 1. A wavelength-tunable laser , comprising:a reflective gain unit;an optical phase shifter;a coupler; and an output port of the reflective gain unit is connected to an input port of the optical phase shifter, and the reflective gain unit is configured to reflect light in a resonant cavity of the laser and provide a gain of the laser,', 'an output port of the optical phase shifter is connected to an input port of the coupler, and the optical phase shifter is configured to adjust a cavity length of the resonant cavity of the laser, so that a cavity mode of the laser matches a center wavelength of a passive filter unit,', 'a first output port of the coupler is connected to an input port of the passive filter unit array, to input, to the passive filter unit array, light to be filtered, and a second output port of the coupler is an output port of the laser, and', 'the passive filter unit array comprises a plurality of passive filter units, wavelength tuning ranges of any two of the plurality of passive filter units are different, and only one of the plurality of passive filter units performs filtering at a of time., 'a passive filter unit array, ...

Spectrometer including tunable on-chip laser and spectrum measurement method

A spectrometer may include: a tunable on-chip laser source configured to irradiate a biological tissue with laser radiation; a photodetector configured to receive the laser radiation reflected from the biological tissue; and at least one processor. The tunable on-chip laser source may include: a semiconductor gain chip having a gain bandwidth for operating the tunable on-chip laser source in a predetermined wavelength range; and a plurality of resonator cavities connected between the semiconductor gain chip and the at least one processor, and configured to perform a coarse high-speed measurement and a fine measurement to measure a spectrum of the laser radiation reflected from the biological tissue.

Thermal Compensation for Burst-Mode Laser Wavelength Drift

An apparatus comprising a burst-mode laser comprising an active layer and configured to emit an optical signal during a burst period, wherein a temperature change of the burst-mode laser causes the optical signal to shift in wavelength, and a heater thermally coupled to the active layer and configured to reduce a wavelength shift of the optical signal during the burst period by applying heat to the active layer based on timing of the burst period.

Semiconductor optical device

A semiconductor optical device includes an SOI substrate having a waveguide of silicon, and at least one gain region of a group III-V compound semiconductor having an optical gain bonded to the SOI substrate. The waveguide has a bent portion and multiple linear portions extending linearly and connected to each other through the bent portion. The gain region is disposed on each of the multiple linear portions.

VARIABLE WAVELENGTH LIGHT SOURCE AND METHOD FOR CONTROLLING WAVELENGTH SWITCHING OF VARIABLE WAVELENGTH LIGHT SOURCE

A wavelength tunable light source includes a wavelength tunable laser device and a control device. The wavelength tunable laser device includes: M laser diodes configured to generate laser oscillation to output beams; a multiplexer/demultiplexer configured to multiplex the beams output from the M laser diodes to bifurcate the beams for output; a first semiconductor optical amplifier configured to amplify one output beam of the bifurcated beams to output a first emitted beam; and a second semiconductor optical amplifier configured to amplify another output beam of the bifurcated beams to output a second emitted beam. The control device is configured to perform wavelength switching control on wavelengths of the first emitted beam and the second emitted beam by switching an electric power input to the second semiconductor optical amplifier. 1. A wavelength tunable light source , comprising:a wavelength tunable laser device configured to output a first emitted beam and a second emitted beam from M beams, M being 2 or more; anda control device configured to perform control so as to switch wavelengths of the first emitted beam and the second emitted beam to a desired value by controlling the wavelength tunable laser device, M laser diodes configured to generate laser oscillation to output beams;', 'a multiplexer/demultiplexer configured to multiplex the beams output from the M laser diodes to bifurcate the beams into a first output beam and a second output beam for output;', 'a first semiconductor optical amplifier configured to amplify the first output beam output from the multiplexer/demultiplexer to output the first emitted beam; and', 'a second semiconductor optical amplifier configured to amplify the second output beam output from the multiplexer/demultiplexer to output the second emitted beam, and, 'wherein the wavelength tunable laser device includeswherein the control device is configured to perform wavelength switching control on the wavelengths of the first ...

Tunable laser with high thermal wavelength tuning efficiency

A monolithically integrated thermal tunable laser comprising a layered substrate comprising an upper surface and a lower surface, and a thermal tuning assembly comprising a heating element positioned on the upper surface, a waveguide layer positioned between the upper surface and the lower surface, and a thermal insulation layer positioned between the waveguide layer and the lower surface, wherein the thermal insulation layer is at least partially etched out of an Indium Phosphide (InP) sacrificial layer, and wherein the thermal insulation layer is positioned between Indium Gallium Arsenide (InGaAs) etch stop layers.

ELECTRICALLY PUMPED VERTICAL CAVITY LASER

Disclosed is an electrically pumped vertical cavity laser structure operating in the mid-infrared region, which has demonstrated room-temperature continuous wave operation. This structure uses an interband cascade gain region, two distributed mirrors, and a low-loss refractive index waveguide. A preferred embodiment includes at least one wafer bonded GaAs-based mirror. 1. An electrically pumped vertical cavity laser (VCL) having an optical cavity and emitting at an emission wavelength , said VCL comprising a plurality of layers , a multi-layer first mirror , a multi-layer second mirror , an interband cascade gain region , a first injection contact , a second injection contact , and a refractive index waveguide comprising an inner region of a higher distributed refractive index and an outer region of lower distributed refractive , wherein said higher distributed refractive index exceeds said lower distributed refractive index by less than about 0.12.2. The VCL of claim 1 , wherein a percentage of injected current overlapping with the optical mode is greater than about 25%.3. The VCL of claim 1 , wherein said VCL emits in a single transverse and longitudinal mode.4. The VCL of claim 1 , wherein said refractive index waveguide comprises an undercut layer with an undercut thickness.5. The VCL of claim 4 , wherein said undercut layer comprises at least one material from the group consisting of InAsSb and InAs.6. The VCL of claim 4 , wherein said undercut thickness is less than about a quarter of said emission wavelength divided by refractive index of undercut material.7. The VCL of claim 1 , wherein said refractive index waveguide comprises an oxidized layer of AlGaAs having an oxide thickness.8. The VCL of claim 7 , wherein said oxide thickness is less than about a quarter of said emission wavelength divided by the unoxidized region refractive index.9. The VCL of claim 7 , wherein said oxidized layer comprises a tapered thickness.10. The VCL of claim 1 , wherein said ...

SMALL FORM FACTOR TRANSMITTING DEVICE

A packaged transmitter device includes a base member comprising a planar part mounted with a thermoelectric cooler, a transmitter, and a coupling lens assembly, and an assembling part connected to one side of the planar part. The device further includes a circuit board bended to have a first end region and a second end region being raised to a higher level. 1. A method of packaging a photonic transceiver comprising:providing a base member comprising a planar part extended to an assembling part;mounting a thermoelectric cooler module, a transmitter module, and an optical coupling lens assembly on a top surface of the planar part;disposing a circuit board bended in step-shape with a first end region sitting on a top surface of the planar part and a second end region being a raised level, the first end region comprising multiple electrical connection patches respectively connected to the thermoelectric module and the transmitter module, the second end region comprising an electrical port for external connection;disposing a cover member to a fixed position over the planar part to at least cover the thermoelectric module, the transmitter module, the optical coupling lens assembly, and the first end region of the circuit board;assembling a cylindrical member to the assembling part, the cylindrical member enclosing an isolator aligned to the optical coupling lens assembly along its axial line and connected to a first optical fiber to output optical signal from the transmitter module; andmounting the base member on a PCB board.2. The method of wherein the mounting the thermoelectric cooler module comprises disposing a plurality of single-stage thermoelectric units sandwiched between a hot side surface and a cold side surface;attaching the hot side surface to a first submount inside a semi-hollow region recessed from the top surface of the planar part; andattaching the cold side surface partially with a second submount.3. The method of wherein the mounting the transmitter ...

TUNABLE LASER WITH DIRECTIONAL COUPLER

A tunable laser has a first mirror, a second mirror, a gain medium, and a directional coupler. The first mirror and the second mirror form an optical resonator. The gain medium and the directional coupler are, at least partially, in an optical path of the optical resonator. The first mirror and the second mirror comprise binary super gratings. Both the first mirror and the second mirror have high reflectivity. The directional coupler provides an output coupler for the tunable laser. 1. (canceled)2. A method for coupling silicon waveguides , the method comprising: the directional coupler has a shoulder;', 'the directional coupler has a first ridge extending from the first input to a first output disposed on the shoulder; and', 'the directional coupler has a second ridge extending from a second input to a second output disposed on the shoulder;, 'guiding light into a first input of a directional coupler, whereinguiding light from the first input to the first ridge;guiding light from the first ridge, through the shoulder to the second ridge, wherein the first ridge tapers to direct at least a portion of light, from the first input, out of the first ridge toward the second ridge; andguiding light from the second ridge to the second output.3. The method as recited in claim 2 , wherein the first ridge claim 2 , the second ridge claim 2 , and the shoulder are made of silicon.4. The method as recited in claim 3 , wherein:the first ridge, the second ridge, and the shoulder are made of crystalline silicon; andthe shoulder is disposed on a silicon substrate.5. The method as recited in claim 2 , wherein:the shoulder tapers in a first region;the first ridge and the second ridge taper in a second region;the first ridge and the second ridge taper in an opposite direction in a third region than in the second region;the shoulder tapers in an opposite direction in a fourth region than in the first region;the second region is between the first region and the third region; andthe third ...

THERMAL MANAGEMENT OF LASER DIODE MODE HOPPING FOR HEAT ASSISTED MEDIA RECORDING

A method and apparatus provide for determining a temperature at a junction of a laser diode when the laser diode is operated in a lasing state that facilitates heat-assisted magnetic recording, comparing the junction temperature and an injection current supplied during the lasing state to stored combinations of junction temperature and injection current, and determining a likelihood of mode hopping occurring for the laser diode during the lasing state based on the comparison to stored combinations of junction temperature and injection current. 1. An apparatus , comprising: a read element and a write element respectively situated at an air bearing surface (ABS) of the slider;', 'a near-field transducer (NFT) situated at the ABS proximate the write element;', 'an optical waveguide configured to couple light from the laser diode to the NFT;', 'a temperature sensing arrangement configured to calculate a temperature of the laser diode junction based on a voltage differential between a non-steady lasing state of the laser diode and a steady state lasing state of the laser diode; and', 'a heater arrangement disposed on the slider and configured to heat the junction of the laser diode during least a portion of the non-lasing state and at least a portion of the lasing state of the laser diode., 'a slider and a laser diode configured to facilitate heat assisted magnetic recording (HAMR), the slider comprising2. The apparatus of claim 1 , wherein the heater arrangement and the laser diode define independent circuits.3. The apparatus of claim 1 , wherein the heater arrangement and the laser diode are configured to be independently controllable.4. The apparatus of claim 1 , comprising:a heater control coupled to the heater arrangement; anda laser control coupled to the laser diode;wherein the heater control and the laser control define independently controllable circuits.5. The apparatus of claim 1 , wherein the heater arrangement is electrically coupled to the laser diode.6. ...

TUNABLE SEMICONDUCTOR LASER BASED ON RECONSTRUCTION-EQUIVALENT CHIRP AND SERIES MODE OR SERIES AND PARALLEL HYBRID INTEGRATION, AND PREPARATION THEREOF

A tunable distributed feedback (DFB) semiconductor laser based on a series mode or a series and parallel hybrid mode. A grating structure of the laser is a sampling Bragg grating based on the reconstruction-equivalent chirp technology. DFB lasers with different operating wavelengths based on the reconstruction-equivalent chirp technology are integrated together by a sampling series combination mode or a series/parallel hybrid mode, one of the lasers is selected to operate via a current, and the operating wavelength of the laser can be controlled by adjusting the current or the temperature, so that the continuous tuning of the operating wavelengths of the lasers can be realized. Various wavelength signals in parallel channels are coupled and then output from the same waveguide. An electrical isolation area (-) is adopted between lasers connected in series or lasers connected in series and connected in parallel to reduce the crosstalk between adjacent lasers. 1. A tunable distributed feedback (DFB) semiconductor laser in series or series/parallel hybrid configurations , and the grating of each DFB section being sampled Bragg grating based on reconstruction-equivalent chirp (REC) technique , wherein the DFB laser sections with different wavelengths are designed based on the REC technique , and integrated together as a tunable device in series or series/parallel hybrid configuration , the laser section is chosen by current injection , and the wavelength tuning is realized by changing temperature , so the tunable laser has continuous wavelength tuning all of the wavelengths from the parallel branches are coupled together by a wavelength multiplexer and output from a single output waveguide.2. The tunable DFB semiconductor laser in series or series/parallel hybrid configuration according to claim 1 , wherein the laser sections are electrically isolated from each other by an isolation gap claim 1 , so that each laser section can be controlled independently.3. The tunable ...

Tunable Waveguide Devices

Methods, systems, and apparatus, including a laser including a layer having first and second regions, the first region including a void; a mirror section provided on the layer, the mirror section including a waveguide core, at least part of the waveguide core is provided over at least a portion of the void; a first grating provided on the waveguide core; a first cladding layer provided between the layer and the waveguide core and supported by the second region of the layer; a second cladding layer provided on the waveguide core; and a heat source configured to change a temperature of at least one of the waveguide core and the grating, where an optical mode propagating in the waveguide core of the mirror section does not incur substantial loss due to interaction with portions of the mirror section above and below the waveguide core. 1. A laser comprising:a layer having first and second regions, the first region including a void, the layer being provided over a substrate; a waveguide core, at least part of the waveguide core is provided over at least a portion of the void;', 'a grating having a plurality of grating groups provided along at least a portion of a length of the mirror;', 'a first cladding provided between the layer and the waveguide core, wherein at least a portion of the first cladding is provided over at least a portion of the second region of the layer;', 'a second cladding provided on the waveguide core; and', 'a heat source configured to change a temperature of at least one of the waveguide core or the grating; and, 'a mirror section provided on the layer, the mirror section comprisinga plurality of support legs being provided between the waveguide core and the substrate,wherein the mirror section has a substantially uniform thermal distribution along the mirror section, andwherein at least part of one of the plurality of support structures is misaligned relative to at least a portion of one of the plurality of grating groups.2. The laser of claim 1 ...

Tunable Waveguide Devices

Methods, systems, and apparatus, including a laser including a layer having first and second regions, the first region including a void; a mirror section provided on the layer, the mirror section including a waveguide core, at least part of the waveguide core is provided over at least a portion of the void; a first grating provided on the waveguide core; a first cladding layer provided between the layer and the waveguide core and supported by the second region of the layer; a second cladding layer provided on the waveguide core; and a heat source configured to change a temperature of at least one of the waveguide core and the grating, where an optical mode propagating in the waveguide core of the mirror section does not incur substantial loss due to interaction with portions of the mirror section above and below the waveguide core. 1. A semiconductor laser , comprising:a substrate;a layer formed on the substrate, the layer having first and second regions, the first region of the layer including one or more voids; a first waveguide core;', 'a p-type region and an n-type region that form a p-n junction; and', 'a contact layer configured to apply a voltage to forward bias the p-n junction of the gain section;, 'a gain section provided on the layer, the gain section comprising a second waveguide core, wherein at least part of the second waveguide core is provided over a first void;', 'a first grating; and', 'a first heat source configured to change a temperature of the second waveguide core or the first grating;, 'a first mirror section provided on the layer, the first mirror section comprising a third waveguide core; and', 'a second heat source configured to change a temperature of the third waveguide core;, 'a phase section provided on the layer, the phase section comprising a fourth waveguide core, wherein at least part of the fourth waveguide core is provided over a second void;', 'a second grating; and', 'a third heat source configured to change a temperature of ...

Tunable Waveguide Devices

Methods, systems, and apparatus, including a laser including a layer having first and second regions, the first region including a void; a mirror section provided on the layer, the mirror section including a waveguide core, at least part of the waveguide core is provided over at least a portion of the void; a first grating provided on the waveguide core; a first cladding layer provided between the layer and the waveguide core and supported by the second region of the layer; a second cladding layer provided on the waveguide core; and a heat source configured to change a temperature of at least one of the waveguide core and the grating, where an optical mode propagating in the waveguide core of the mirror section does not incur substantial loss due to interaction with portions of the mirror section above and below the waveguide core.

LIGHTING DEVICE

Provided is a lighting device using semiconductor laser elements that can be safely used even in a cold region etc. The present invention includes: a plurality of semiconductor laser elements; a temperature sensor that measures an ambient temperature of the plurality of semiconductor laser elements; and a current controller that controls current supply to the semiconductor laser elements, wherein, when a measured value from the temperature sensor is equal to or less than a predetermined first threshold temperature, the current controller does not supply a current equal to or greater than a threshold current, which is required to emit laser light, to the semiconductor laser elements until the measured value exceeds the first threshold temperature, and when the measured value exceeds the first threshold temperature, the current controller supplies a current equal to or greater than the threshold current to the semiconductor laser elements. 1. A lighting device comprising:a plurality of semiconductor laser elements;a temperature sensor that measures an ambient temperature of the plurality of semiconductor laser elements; anda current control unit that controls current supply to the semiconductor laser elements, wherein,when a measured value from the temperature sensor is equal to or less than a predetermined first threshold temperature, the current control unit does not supply a current equal to or greater than a threshold current, which is required to emit laser light, to the semiconductor laser elements until the measured value exceeds the first threshold temperature, andwhen the measured value exceeds the first threshold temperature, the current control unit supplies a current equal to or greater than the threshold current to the semiconductor laser elements.2. The lighting device according to claim 1 , wherein the first threshold temperature is equal to or greater than 0° C.3. The lighting device according to claim 1 , comprising a heater claim 1 , wherein claim 1 ...

THERMAL MANAGEMENT OF LASER DIODE MODE HOPPING FOR HEAT ASSISTED MEDIA RECORDING

A method and apparatus provide for determining a temperature at a junction of a laser diode when the laser diode is operated in a lasing state that facilitates heat-assisted magnetic recording, comparing the junction temperature and an injection current supplied during the lasing state to stored combinations of junction temperature and injection current, and determining a likelihood of mode hopping occurring for the laser diode during the lasing state based on the comparison to stored combinations of junction temperature and injection current. 1. An apparatus , comprising:a slider configured to facilitate heat assisted magnetic recording (HAMR);a laser diode disposed in the slider;a read element and a write element respectively situated at an air bearing surface (ABS) of the slider;a near-field transducer (NFT) situated at the ABS proximate the write element;an optical waveguide configured to couple light from the laser diode to the NFT; anda heater arrangement disposed in, along, or adjacent the laser diode and configured to heat a junction of the laser diode during one or both of at least a portion of the non-lasing state and at least a portion of the lasing state of the laser diode.2. The apparatus of claim 1 , wherein the heater arrangement is configured to heat the junction of the laser diode during at least the portion of the non-lasing state and at least the portion of the lasing state of the laser diode.3. The apparatus of claim 1 , wherein the heater arrangement is disposed in the laser diode.4. The apparatus of claim 1 , wherein the slider has a laser-in-slider (LIS) configuration.5. The apparatus of claim 1 , comprising a temperature sensing arrangement configured to determine a temperature of a junction of the laser diode.6. The apparatus of claim 1 , comprising:a temperature sensing arrangement coupled to the laser diode and configured to determine a temperature of a junction of the laser diode;wherein the temperature sensing arrangement is configured ...

TUNABLE LASER WITH INTEGRATED WAVELENGTH REFERENCE

In the prior art, tunable lasers utilizing silicon-based tunable ring filters and III-V semiconductor-based gain regions required the heterogeneous integration of independently formed silicon and III-V semiconductor based optical elements, resulting in large optical devices requiring a complex manufacturing process (e.g., airtight packaging to couple the devices formed on different substrates, precise alignment for the elements, etc.). Embodiments of the invention eliminate the need for bulk optical elements and hermetic packaging, via the use of hybridized III-V/silicon gain regions and silicon optical components, such as silicon wavelength filters and stabilized wavelength references, thereby reducing the size and manufacturing complexity of tunable lasing devices. 1. (canceled)2. A method for producing wavelength-stabilized light , the method comprising:propagating light in a waveguide through a gain region of a silicon substrate and through a tunable ring filter defined by the silicon substrate to form amplified, wavelength-filtered light in the waveguide;extracting a portion of the amplified, wavelength-filtered light from the waveguide;propagating the extracted light through a stabilized wavelength reference positioned exterior to the waveguide; andheating at least a portion of the stabilized wavelength reference to stabilize a temperature of the stabilized wavelength reference and thereby stabilize a wavelength filtered by the tunable ring filter.3. The method of claim 2 , wherein the stabilized wavelength reference includes at least one of an etalon claim 2 , an interference filter claim 2 , or an optical grating.4. The method of claim 2 , wherein the waveguide forms a laser cavity that includes the gain region and the tunable ring filter claim 2 , and extends to an output coupler that extracts the portion of the amplified claim 2 , wavelength-filtered light from the waveguide.5. The method of claim 4 , wherein the stabilized wavelength reference is ...

SMALL FORM FACTOR TRANSMITTING DEVICE

A packaged transmitter device includes a base member comprising a planar part mounted with a thermoelectric cooler, a transmitter, and a coupling lens assembly, and an assembling part connected to one side of the planar part. The device further includes a circuit board bended to have a first end region and a second end region being raised to a higher level. The first end region disposed on a top surface of the planar part includes multiple electrical connection patches respectively connected to the thermoelectric and the transmitter. The second end region includes an electrical port for external connection. Additionally, the device includes a cover member disposed over the planar part. Furthermore, the device includes a cylindrical member installed to the assembling part for enclosing an isolator aligned to the coupling lens assembly along its axis and connected to a fiber to couple optical signal from the transmitter to the fiber. 1. A pluggable optical communication device comprising:a circuit substrate having a connector pluggable into a network system; and receive optical signals from an optical port coupled to the silicon photonics chip;', 'convert the optical signals into electrical signals; and', 'extract from the electrical signals communications data and output the communications data to the network system via the connector., 'a silicon photonics chip coupled to the circuit substrate, the silicon photonics chip configured to2. The pluggable optical communication device of wherein the circuit substrate is a printed circuit board.3. The pluggable optical communication device of wherein the pluggable connector is integrally formed in the circuit substrate.4. The pluggable optical communication device of wherein the silicon photonics chip is mounted on the circuit substrate.5. The pluggable optical communication device of wherein the silicon photonics chip comprises a fiber-to-silicon attachment claim 1 , wherein the optical port is coupled to the silicon ...

WAVELENGTH-TUNABLE III-V/Si HYBRID OPTICAL TRANSMITTER

An optical transmitter includes a reflective semiconductor optical amplifier (RSOA) coupled to an input end of a first optical waveguide. An end of the first optical waveguide provides a transmitter output for the optical transmitter. Moreover, a section of the first optical waveguide between the input end and the output end is optically coupled to a ring modulator that modulates an optical signal based on an electrical input signal. A passive ring filter (or a 1×N silicon-photonic switch and a bank of band reflectors) is connected to provide a mirror that reflects light received from the second optical waveguide back toward the RSOA to form a lasing cavity. Moreover, the ring modulator and the passive ring filter have different sizes, which causes a Vernier effect that provides a large wavelength tuning range for the lasing cavity in response to tuning the ring modulator and the passive ring filter. 1. An optical transmitter , comprising:a reflective semiconductor optical amplifier (RSOA);a ring modulator that modulates an optical signal based on an electrical input signal;a first optical waveguide with an input end and an output end, wherein the input end is coupled to the RSOA, the output end provides a transmitter output for the optical transmitter, and a section of the first optical waveguide between the input end and the output end is optically coupled to the ring modulator;a second optical waveguide optically coupled to the ring modulator; anda passive ring filter optically coupled to the second optical waveguide;wherein the passive ring filter is connected to provide a mirror that reflects light received from the second optical waveguide back toward the RSOA to form a lasing cavity, wherein the lasing cavity includes the RSOA, the first optical waveguide, the ring modulator, the second optical waveguide and the passive ring filter; andwherein the ring modulator and the passive ring filter have different sizes, which causes a Vernier effect that provides a ...

TUNING A MULTI-CHANNEL OPTICAL TRANSMISSION SYSTEM

An optical transmission system includes a laser module generating a modulated optical waveform, including both amplitude and frequency modulation, at center frequencies corresponding to different operating temperatures; and an optical shaping filter, with passbands corresponding to the different center frequencies, that converts at least part of the frequency modulation to additional amplitude modulation. The optical transmission system is tuned by: determining a range of temperatures at which the laser module center frequencies are within a passband of the optical shaping filter; setting the laser module to a temperature, within the range of temperatures, at which the modulated optical waveform is within the passband; measuring an average output power of the optical shaping filter; and adjusting the temperature of the laser module to a target temperature, within the range of temperatures, at which an output condition is achieved, based on the average output power and/or extinction ratio of the filtered waveform. 1. An optical transmission system comprising:a laser module configured to generate a modulated optical waveform at any one of a plurality of center frequencies corresponding to a plurality of operating temperatures of the laser module, the modulated optical waveform comprising both amplitude modulation and frequency modulation;an optical shaping filter that is configured to implement a plurality of passbands corresponding to the center frequencies of the modulated optical waveform, and that is configured to convert at least part of the frequency modulation in the modulated optical waveform to additional amplitude modulation for the modulated optical waveform; and for a first passband among the plurality of passbands of the optical shaping filter, determining a first range of temperatures at which the laser module generates the modulated optical waveform at center frequencies that are within the first passband;', 'setting the laser module to a first ...

Underwater lidar

The disclosure relates in some aspects to Light Detection and Ranging (LIDAR) for underwater applications. An exemplary LIDAR system described herein uses a green and/or blue semiconductor laser, which is self-injection locked using a high-quality factor micro-resonator, such as a whispering gallery mode (WGM) resonator. The self-injection locking results in a single mode operation of the laser and reduction of its linewidth. The self-injection allows transferring frequency modulation from the optical micro-resonator to the laser frequency without significant impact on the power of the laser. In some examples, the LIDAR operates in a continuous wave frequency modulated (CWFM) mode. The CWFM LIDAR may be used for ranging, velocity determination, etc., particularly for underwater applications and may be mounted to watercraft or to aircraft designed to fly over water to take underwater measurements.

SILICON PHOTONICS BASED TUNABLE LASER

A tunable laser device based on silicon photonics includes a substrate configured with a patterned region comprising one or more vertical stoppers, an edge stopper facing a first direction, a first alignment feature structure formed in the patterned region along the first direction, and a bond pad disposed between the vertical stoppers. Additionally, the tunable laser includes an integrated coupler built in the substrate located at the edge stopper and a laser diode chip including a gain region covered by a P-type electrode and a second alignment feature structure formed beyond the P-type electrode. The laser diode chip is flipped to rest against the one or more vertical stoppers with the P-type electrode attached to the bond pad and the gain region coupled to the integrated coupler. Moreover, the tunable laser includes a tuning filter fabricated in the substrate and coupled via a wire waveguide to the integrated coupler. 1. A tunable laser device based on silicon photonics comprising:a substrate configured with a patterned region comprising one or more vertical stoppers, an edge stopper facing a first direction, a first alignment feature structure formed in the patterned region along the first direction, and a bond pad disposed between the vertical stoppers;an integrated coupler built in the substrate located at the edge stopper;a laser diode chip including a gain region covered by a P-type electrode and a second alignment feature structure formed beyond the P-type electrode, the laser diode chip being flipped to rest against the one or more vertical stoppers with the P-type electrode attached to the bond pad and the gain region coupled to the integrated coupler; anda tuning filter fabricated in the substrate and coupled via a wire waveguide to the integrated coupler;wherein the tunable filter comprises a wire waveguide having a straight section coupled to at least two ring resonators followed by a reflector section, the strain section being directly coupled to the ...

Systems and Methods for Reducing Adjacent Channel Leakage Ratio

An analog radio over fiber (AROF) wavelength division multiplexing (WDM) system and method for reducing adjacent channel leakage ratio (ACLR) in a radio frequency signal provided by an AROF WDM system are provided. The AROF WDM system comprises a plurality of transmitters, a multiplexer, a demultiplexer, a plurality of receivers and a controller. Each transmitter is for receiving a radio frequency input signal and for modulating the radio frequency input signal onto an optical signal to obtain a modulated optical signal. The multiplexer is for receiving each modulated optical signal from the plurality of transmitters and for combining the modulated optical signals into a combined optical signal to be sent a distance over an optical fiber. The multiplexer has a pluralities of passbands with each passband having a center wavelength. The demultiplexer is for receiving the combined optical signal and for separating the combined optical signal back into the individual modulated optical signals. Each receiver is for receiving one of the modulated optical signals from the demultiplexer and for converting the received modulated optical signal into a radio frequency output signal. The controller is configured to detune, for each transmitter, one of that transmitter and the multiplexer relative to the other such that a wavelength of the modulated optical signal transmitted by that transmitter is longer than the center wavelength of a corresponding one of the plurality of passbands of the multiplexer. 1. An analog radio over fiber (AROF) wavelength division multiplexing (WDM) system comprising:a plurality of transmitters, each transmitter configured to modulate a respective radio frequency input signal onto an optical signal to generate a corresponding modulated optical signal;a multiplexer configured to combine the modulated optical signals into a combined optical signal the multiplexer having a plurality of passbands corresponding to channels of the AROF WDM system, each ...

LASER LIGHT SOURCE DEVICE

Provided is a laser light source device stably operating, stably emitting laser light having a predetermined wavelength, and ensuring lower power consumption than that of the related art. The laser light source device includes a semiconductor laser element, a heat radiation part provided on one surface side of the semiconductor laser element, a heat conductive part having heat conductive characteristics, provided in contact with the one surface of the semiconductor laser element and the heat radiation part, configured to conduct heat generated in the semiconductor laser element to the heat radiation part, a wavelength measuring part configured to measure a wavelength of laser light, and a heat conductive characteristic control part configured to change the heat conductive characteristics of the heat conductive part based on the wavelength of the laser light, and control the wavelength of the laser light to fall within a predetermined wavelength range. 1. A laser light source device , comprising:a semiconductor laser element configured to emit laser light;a heat radiation part provided on a side of one surface of the semiconductor laser element;a heat conductive part having heat conductive characteristics, provided in contact with the one surface of the semiconductor laser element and the heat radiation part, configured to conduct heat generated in the semiconductor laser element to the heat radiation part;a wavelength measuring part configured to measure a wavelength of the laser light; anda heat conductive characteristic control part configured to change the heat conductive characteristics of the heat conductive part based on the wavelength of the laser light measured by the wavelength measuring part, and control the wavelength of the laser light to fall within a predetermined wavelength range.2. The laser light source device according to claim 1 ,wherein the heat conductive part is held between the semiconductor laser element and the heat radiation part,the heat ...

ULTRA-LOW NOISE, HIGHLY STABLE SINGLE-MODE OPERATION, HIGH POWER, BRAGG GRATING BASED SEMICONDUCTOR LASER

A laser including: a gain chip; an external cavity incorporating a Bragg grating; and a baseplate; wherein a first end of the gain chip has a high reflectivity facet forming a first end of the laser cavity; a second end of the gain chip has a low reflectivity facet; and a second part of the external cavity comprises a Bragg grating, supported by the baseplate, the temperature of the baseplate being maintained through a feedback loop; wherein the optical length of the external cavity is at least an order of magnitude greater than the optical length of the gain chip; wherein the Bragg grating is physically long and occupies a majority of the length of the external cavity and is apodized to control the sidemodes of the grating reflection. 121-. (canceled)22. A laser comprising:a semiconductor gain chip to generate light; and wherein a first end of the gain chip has a high reflectivity facet forming a first end of a laser cavity; a second end of the gain chip has a low reflectivity facet, allowing light generated from the gain chip to be coupled to the first end of the waveguide external cavity,', 'wherein the physical length of the Bragg grating is greater than 20 mm and occupies at least 75% of the physical length of the waveguide external cavity., 'a waveguide external cavity having a first end and a second end and including an integrated Bragg grating to reflect at least a portion of the light'}23. The laser of claim 22 , wherein the Bragg grating is apodized to control the sidemodes of the grating reflection.24. The laser of claim 22 , wherein the physical length of the Bragg grating is greater than 40 mm and occupies at least 75% of the physical length of the external cavity.25. The laser of claim 22 , wherein the optical length of the external cavity is at least an order of magnitude greater than the optical length of the gain chip.26. The laser of claim 22 , wherein the optical length of the external cavity is at least about twenty times the optical length of ...

ULTRA-LOW NOISE, HIGHLY STABLE SINGLE-MODE OPERATION, HIGH POWER, BRAGG GRATING BASED SEMICONDUCTOR LASER

A laser including: a gain chip; an external cavity incorporating a Bragg grating; and a baseplate; wherein a first end of the gain chip has a high reflectivity facet forming a first end of the laser cavity; a second end of the gain chip has a low reflectivity facet; and a second part of the external cavity comprises a Bragg grating, supported by the baseplate, the temperature of the baseplate being maintained through a feedback loop; wherein the optical length of the external cavity is at least an order of magnitude greater than the optical length of the gain chip; wherein the Bragg grating is physically long and occupies a majority of the length of the external cavity and is apodized to control the sidemodes of the grating reflection. 121-. (canceled)22. A laser comprising:a semiconductor gain element to generate light;an external cavity with integrated Bragg grating monolithically integrated with the gain element;wherein a first end of the gain element has a high reflectivity forming a first end of a laser cavity; a second end of the gain element has a low reflectivity, allowing light generated from the gain element to be coupled with a first end of the external cavity, and the Bragg grating forming a second end of the laser cavity;wherein the physical length of the Bragg grating is greater than 20 mm and occupies at least 75% of the physical length of the external cavity.23. The laser of claim 22 , wherein the Bragg grating is apodized to control the sidemodes of the grating reflection.24. The laser of claim 22 , wherein the physical length of the Bragg grating is greater than 40 mm and occupies at least 75% of the physical length of the external cavity.25. The laser of claim 22 , wherein the optical length of the external cavity is at least an order of magnitude greater than the optical length of the gain element.26. The laser of claim 22 , wherein the external cavity comprises a low loss waveguide material.27. The laser of claim 22 , further comprising a ...

Independent Control of Emission Wavelength and Output Power of a Semiconductor Laser

Methods for driving a tunable laser with integrated tuning elements are disclosed. The methods can include modulating the tuning current and laser injection current such that the laser emission wavelength and output power are independently controllable. In some examples, the tuning current and laser injection current are modulated simultaneously and a wider tuning range can result. In some examples, one or both of these currents is sinusoidally modulated. In some examples, a constant output power can be achieved while tuning the emission wavelength. In some examples, the output power and tuning can follow a linear relationship. In some examples, injection current and tuning element drive waveforms necessary to achieve targeted output power and tuning waveforms can be achieved through optimization based on goodness of fit values between the targeted and actual output power and tuning waveforms. 120-. (canceled)21. A method of driving a semiconductor laser , comprising:applying a laser injection current to the semiconductor laser to generate a laser output power targeting a predetermined output power; andapplying a tuning current to a tuning element to generate a laser emission wavelength targeting a predetermined laser emission wavelength; wherein the semiconductor laser and the tuning element are configured to control the laser emission wavelength and the laser output power of the semiconductor laser independently of one another.22. The method of claim 21 , further comprising:varying the laser injection current while maintaining an approximately consistent submount temperature such that the laser output power is linearly dependent on the laser injection current.23. The method of claim 22 , wherein the laser output power is linearly dependent on the laser injection current when the laser injection current exceeds a laser threshold current.24. The method of claim 23 , further comprising:determining a laser slope efficiency based at least in part on the linear ...

WAVELENGTH TUNABLE SEMICONDUCTOR LASER HAVING TWO DIFRACTIVE GRATING AREAS

A semiconductor laser has a first diffractive grating area. The first diffractive grating area has a plurality of segments. Each segment has a first area including a diffractive grating and a second area that is space area combined to the first area. Optical lengths of at least two of the second areas are different from each other. A refractive-index of each of the segments are changeable. 1. A semiconductor laser comprising:a first diffractive grating area that has a plurality of segments; anda second diffractive grating area that has another plurality of segments,wherein each of the plurality of segments of said first diffractive grating area has a first area including a diffractive grating and a second area that is a space area combined to the first area, optical lengths of at least two of the second areas being different from each other, and a refractive-index of each of the segments being changeable,wherein each of the plurality of segments of said second diffractive grating area has a first area including a diffractive grating and a second area that is a space area combined to the first area, optical lengths of at least two of the second areas being different from each other, and a refractive-index of each of the segments being changeable, andwherein a length of the first area is shorter than a length of the second area.2. The semiconductor laser as claimed in claim 1 , wherein the first diffractive grating area or the second diffractive grating area has a gain region.3. The semiconductor laser as claimed in further comprising a gain region between the first diffractive grating area and the second diffractive grating area.4. The semiconductor laser as claimed in claim 1 , wherein a minimum difference between the optical lengths of the second areas is within 1 to 6% of an average optical length of the second areas in the first diffractive grating area or/and the second diffractive grating area.5. The semiconductor laser as claimed in wherein minimum differences ...

LASER DEVICE

To provide a laser device capable of detecting overheating (abnormality) of a heat-generating part by detecting a temperature of a cooling member for cooling the heat-generating part. A laser device includes one or a plurality of heat-generating part(s), one or a plurality of cooling member(s) respectively disposed in contact with the one or plurality of heat-generating part(s), the one or plurality of cooling member(s) containing a refrigerant flowing inside, one or a plurality of first temperature detection part(s) respectively disposed on the one or plurality of cooling member(s) to respectively detect temperatures of the one or plurality of cooling member(s), and a monitoring part capable of detecting an abnormality respectively in the one or plurality of cooling member(s) based on temperature information including information on the temperatures detected by the one or plurality of first temperature detection part(s). 1. A laser device comprising:one or a plurality of heat-generating part(s);one or a plurality of cooling member(s) respectively disposed in contact with the one or plurality of heat-generating part(s), the one or plurality of cooling member(s) containing a refrigerant flowing inside;one or a plurality of first temperature detection part(s) respectively disposed on the one or plurality of cooling member(s) to respectively detect the temperatures of the one or plurality of cooling member(s); anda monitoring part capable of detecting abnormalities respectively in the one or plurality of cooling member(s) based on temperature information including information on the temperatures detected by the one or plurality of first temperature detection part(s).2. The laser device according to claim 1 , the laser device further comprising:a refrigerant passage connecting a cooling device disposed externally and the one or plurality of cooling member(s) so as to allow the refrigerant to circulate inside, the refrigerant passage including:a supply passage for ...

Quantum cascade laser

A quantum cascade laser includes a semiconductor substrate, an optical waveguide formed on a first surface of the semiconductor substrate, and a temperature adjusting member. The optical waveguide includes a first region and a second region located on one side with respect to the first region in the optical waveguide direction of the optical waveguide. The first region generates a first light having a first wavelength, and the second region generates a second light having a second wavelength. The optical waveguide generates an output light having a frequency corresponding to a difference between the first wavelength and the second wavelength by difference-frequency generation. A recess for suppressing heat transfer between the first region and the second region is formed at a second surface of the semiconductor substrate. The temperature adjusting member includes a first temperature adjusting member for adjusting the temperature of the second region.

Temperature Control Of An Optical Device

The present disclosure is directed to an optical device including at least one temperature-dependent tunable element for controlling a wavelength of an optical signal, a first temperature control circuit for controlling a temperature of a first region of the optical device; and a second temperature control circuit for controlling a temperature of a second region of the optical device. The second region may include a portion of the first region. The second region may be smaller than the first region. The tunable element may be positioned in the second region such that a temperature of the tunable element is controlled based on the second temperature control circuit controlling the temperature of the second region. The tunable element may be one of (i) a laser for transmitting an outgoing optical signal and (ii) an optical filter coupled to a photodetector for receiving an incoming optical signal. 1. An optical device comprising:at least one temperature-dependent tunable element for controlling a wavelength of an optical signal, wherein the tunable element is one of (i) a laser for transmitting an outgoing optical signal and (ii) an optical filter coupled to a photodetector for receiving an incoming optical signal;a first temperature control circuit for controlling a temperature of a first region of the optical device; anda second temperature control circuit for controlling a temperature of a second region of the optical device, wherein the second region includes a portion of the first region, wherein the second region is smaller than the first region, and wherein the tunable element is positioned in the second region such that a temperature of the tunable element is controlled based on the second temperature control circuit controlling the temperature of the second region.2. The optical device of claim 1 , wherein at least one of the first and second temperature control circuits is a thermoelectric cooler.3. The optical device of claim 1 , wherein the second ...

Semiconductor Optical Module

A semiconductor optical module includes a semiconductor laser element region having an active layer, a first cladding layer which is formed such that the active layer is embedded therein, a second cladding layer which is formed underneath the active layer and the first cladding layer, and a heater unit which produces a temperature change in a waveguide; an optical waveguide element region including a spot-size converter which converts a spot size of incident laser light, and an optical waveguide core layer which is formed such that the spot-size converter is embedded therein, the first cladding layer contains InP, the second cladding layer is made of a material lower in refractive index and higher in thermal conductivity than the first cladding layer, and a third cladding layer which is made of a material lower in refractive index and lower in thermal conductivity than the second cladding layer is formed underneath the spot-size converter and the heater unit.

MULTIWAVELENGTH QUANTUM CASCADE LASER VIA GROWTH OF DIFFERENT ACTIVE AND PASSIVE CORES

Disclosed is a laser source capable of producing mid-IR laser radiation comprises growing a first core structure on a substrate, etching away the first core structure in one or more locations, and growing a second core structure on the substrate. At least one of the core structures comprises a quantum cascade gain medium emitting at a frequency within the range from 3-14 μm. Also disclosed is a laser source capable of producing mid-IR laser radiation comprising a quantum-cascade core positioned on a substrate for emitting within the range from 3-14 μm and a second core on the substrate positioned in-plane relative to the first core. The second core is one of a) a passive waveguide core b) a second quantum-cascade core and c) a semiconductor active core region. 1. A laser source capable of producing mid-IR laser radiation , the source comprising:a quantum-cascade core positioned on a substrate and structured for generating intersubband transitions emitting at a first center frequency within the range from 3-14 μm; anda second core on the substrate and positioned in-plane relative to the first core, wherein the second core is one of:a) a passive waveguide core made comprising one of AlInAs, InGaAs, GaInAsP, or AlGaInAs, and structured to guide wavelengths having said first center frequency,b) a second quantum-cascade core structured for generating intersubband transitions emitting at a second center frequency within the range from 3-14 μm different from said first center frequency, andc) a semiconductor active core region structured for generating interband transitions emitting at a second center frequency, said second center frequency being different from said first center frequency.2. The laser source according to wherein the second core is a second quantum-cascade core structured for generating intersubband transitions emitting at a second center frequency within the range from 3-14 μm different from said first center frequency.3. The laser source according to ...

SEMICONDUCTOR LASER DIODE LIGHT SOURCE PACKAGE

A semiconductor laser diode light source package includes: a seed light source for outputting signal beams; a pump beam source for outputting pump beams; and at least one mirror for transmitting the signal beams to a core of an output optical fiber and transmitting the pump beams to first cladding of the output optical fiber, wherein the seed light source, the pump beam source, and the at least one mirror are realized in a semiconductor chip, and the output optical fiber is connected to an end terminal of the semiconductor laser diode light source package. 1. A semiconductor laser diode light source package comprising:a seed light source for outputting signal beams;a pump beam source for outputting pump beams; andat least one mirror for transmitting the signal beams to a core of an output optical fiber and transmitting the pump beams to a first cladding of the output optical fiber,wherein the seed light source, the pump beam source, and the at least one mirror are realized in a semiconductor chip, and the output optical fiber is connected to an end terminal of the semiconductor laser diode light source package.2. The semiconductor laser diode light source package of claim 1 , whereinthe output optical fiber is a double clad fiber configured with the core, the first cladding, and secondary cladding.3. The semiconductor laser diode light source package of claim 1 , whereina gain medium is doped to the core of the output optical fiber.4. The semiconductor laser diode light source package of claim 1 , further comprisinga first collimation lens for transforming the signal beams into parallel beams and transmitting the same to the at least one mirror.5. The semiconductor laser diode light source package of claim 1 , whereinthe at least one mirror transmits one of the signal beams and the pump beams and reflects the other thereof to transmit the signal beams to the core of the output optical fiber and transmit the pump beams to the first cladding of the output optical ...

SEMICONDUCTOR LASER

A hybrid single or multi-wavelength laser using an optical gain element, such as a semiconductor optical amplifier (SOA), for example a QD RSOA, and a semiconductor, e.g. silicon, photonics chip is demonstrated. A plurality, e.g. four, lasing modes at a predetermined, e.g. 2 nm, spacing and less than 3 dB power non-uniformity may be observed, with over 20 mW of total output power. Each lasing peak can be successfully modulated at 10 Gb/s. At 10BER, the receiver power penalty is less than 2.6 dB compared to a conventional commercial laser. An expected application is the provision of a comb laser source for WDM transmission in optical interconnection systems. 120-. (canceled)21. A semiconductor laser , comprising:an optical port configured to provide an optical output beam comprising one or more selected optical wavelengths; a first reflector at a first end of the optical cavity, said first reflector comprising a first reflectivity; and', 'a second reflector at a second end of the optical cavity, the second reflector comprising a second reflectivity;, 'an optical cavity, in optical communication with the optical port, comprisingan optical gain medium in the optical cavity for amplifying light at the one or more selected wavelengths;a filter element in the optical cavity between the optical gain medium and the optical port configured to pass light of the one or more selected optical wavelengths therethrough to and from the optical gain medium and deflect wavelengths not of interest away from said optical gain medium and the optical port to suppress stimulated emission of those wavelengths; anda phase tuner capable of adjusting and controlling operating conditions of the laser.22. The laser according to claim 21 , wherein the phase tuner is capable of tuning the laser cavity to at least partially compensate for changing conditions.23. The laser according to claim 21 , wherein the phase tuner is capable of tuning the laser cavity to at least partially compensate for ...

External Cavity Tunable Laser And Cavity Mode Locking Method Thereof

The present invention relates to an external cavity tunable laser and a cavity mode locking method thereof. In an embodiment, an external cavity tunable laser comprises a semiconductor amplifier having a partial reflective film provided on one end and an anti-reflective film provided on the other end, a cavity mirror provided at the anti-reflective end to define an external cavity therebetween, a large-range phasing assembly and a quick phasing assembly provided to adjust the optical length of the external cavity independently, an optical power detector provided to detect the optical power of the light output from the semiconductor amplifier, and a control unit in communication with the optical power detector, the large-range phasing assembly, and the quick phasing assembly. 1. An external cavity tunable laser comprising:a semiconductor amplifier having a partial reflective film provided on one end and an anti-reflective film provided on the other end;a cavity mirror provided at the anti-reflective end of the semiconductor amplifier to define an external cavity therebetween;a large-range phasing assembly and a quick phasing assembly provided to adjust the optical length of the external cavity independently;an optical power detector provided at the partial reflective end of the semiconductor amplifier to detect the optical power of the light output from the semiconductor amplifier; and [{'b': '1', 'sub': 'Max', 'monitoring whether a difference between the output optical power value received from the optical power detector and a previous maximum output optical power value (P) in a cavity mode locking state is higher than a threshold;'}, {'sub': f', 'Max, 'b': '2', 'if yes, changing the driving input (D) of the quick phasing assembly to obtain a present maximum output optical power value (P);'}, {'sub': f', 'f', 'L, 'converting the driving input change (D−CD) of the quick phasing assembly to a driving input change (ΔD) of the large-range phasing assembly; and'}, ' ...

Laser temperature compensation system and driving method thereof

An optical transmitter and a method for driving the optical transmitter include emitting an optical signal using a laser having a lasing cavity with a first section and a second section, performing, using a first heater thermally coupled to the first section, a first temperature control on the first section using a first control signal, and performing, using a second heater thermally coupled to the second section, a second temperature control on the second section using a second control signal. The first temperature control is independent from the second temperature control.

Thermoelectric Cooler, Optical Sub-Assembly, and Optical Module

A thermoelectric cooler (TEC) configured to support a heat source device and perform temperature control on the heat source device. The TEC includes a first base plate, a second base plate disposed opposite to the first base plate, and first elements. The first base plate is configured to support the heat source device. An accommodation space is formed between the first base plate and the second base plate. The first elements are arranged at intervals within the accommodation space, and are all connected to the first base plate and the second base plate. 1. A thermoelectric cooler (TEC) configured to support a heat source device and perform temperature control on the heat source device , wherein the TEC comprises:a first base plate configured to support the heat source device;a second base plate disposed opposite to the first base plate;an accommodation space formed between the first base plate and the second base plate, the accommodation space comprising a first area and a second area adjacent to the first area; anda plurality of first elements arranged at intervals within the accommodation space, connected to the first base plate and the second base plate, and connected to an external power source to adjust a temperature difference between the first base plate and the second base plate by changing a voltage or a current to implement temperature control on the heat source device.2. The TEC of claim 1 , wherein the first elements are all arranged in the first area.3. The TEC of claim 2 , wherein the second area is a vacant area.4. The TEC of claim 1 , wherein the first area is connected to the second area claim 1 , the first elements are arranged in the first area and the second area claim 1 , and the first elements are arranged in such a manner that a density of the first elements gradually decreases in a direction from the first area to the second area.5. The TEC of claim 1 , wherein the first area is connected to the second area claim 1 , the first elements are ...

Semiconductor Structure Having Group III-V Chiplet on Group IV Substrate and Cavity in Proximity to Heating Element

A semiconductor structure includes a group III-V chiplet over a group IV substrate. A group IV optoelectronic device is situated in the group IV substrate. A patterned group III-V optoelectronic device is situated in the group III-V chiplet. A heating element is near the group IV optoelectronic device, or alternatively, near the patterned group III-V optoelectronic device. A dielectric layer is over the patterned group III-V optoelectronic device. A venting hole is in the dielectric layer in proximity of the heating element. A cavity is in the group IV substrate in proximity to the heating element. 1. A semiconductor structure comprising:a group III-V chiplet over a group IV substrate;a group IV optoelectronic device situated in said group IV substrate;a heating element near said group IV optoelectronic device;a patterned group III-V optoelectronic device in said group III-V chiplet;a dielectric layer over said patterned group III-V optoelectronic device;a venting hole in said dielectric layer in proximity of said heating element;a cavity in said group IV substrate in proximity to said heating element.2. The semiconductor structure of claim 1 , wherein said heating element is situated over said cavity.3. The semiconductor structure of claim 1 , wherein said heating element is situated over said group IV optoelectronic device.4. The semiconductor structure of claim 1 , wherein said heating element is situated laterally adjacent to said group IV optoelectronic device.5. The semiconductor structure of claim 1 , wherein said heating element is situated in said group IV substrate.6. The semiconductor structure of claim 1 , wherein said heating element is situated in said group III-V chiplet.7. The semiconductor structure of claim 1 , wherein:said group IV substrate is a semiconductor-on-insulator (SOI) substrate;said cavity is situated in a handle wafer of said SOI substrate.8. The semiconductor structure of claim 1 , wherein said patterned group III-V optoelectronic ...

LASER WAVELENGTH CONTROL DEVICE AND METHOD FOR CONTROLLING LASER WAVELENGTH

A laser wavelength control device, includes a memory; and a processor coupled to the memory and configured to: measure a wavelength of a laser beam emitted by a light source, when the measured wavelength is not in a target wavelength band, adjust a voltage to be applied to the light source such that a wavelength of the laser beam falls within the target wavelength band, and when a wavelength measured after the adjustment of the voltage is not in the target wavelength band, adjust a temperature of the light source such that the wavelength of the laser beam falls within the target wavelength band. 1. A laser wavelength control device , comprising:a memory; and measure a wavelength of a laser beam emitted by a light source,', 'when the measured wavelength is not in a target wavelength band, adjust a voltage to be applied to the light source such that the wavelength of the laser beam falls within the target wavelength band, and', 'when a wavelength measured after the adjustment of the voltage is not in the target wavelength band, adjust a temperature of the light source such that the wavelength of the laser beam falls within the target wavelength band., 'a processor coupled to the memory and configured to2. The laser wavelength control device according to claim 1 , wherein the processor is configured to:receive data which includes the voltage to be applied to the light source, the temperature of the light source, and the wavelength of the laser beam to be emitted by the light source, andadjust the voltage in a first setting range included in the data such that the wavelength of the laser beam becomes a center wavelength of the target wavelength band.3. The laser wavelength control device according to claim 2 , wherein the processor is configured toheat or cool the light source so as to adjust the temperature in a second setting range included in the data such that the wavelength of the laser beam becomes the center wavelength of the target wavelength band.4. The laser ...

Light-Emitting Device Having III-V Semiconductor Gain Section Coupled to Whistle-Geometry Tunable Filter

The invention concerns a wavelength tunable semiconductor laser comprising a laser gain section () optically coupled to an underlying optical waveguide (). According to an embodiment of the invention, a first and a second passive microring resonators () having a whistle geometry, are arranged on both sides of the laser gain section and evanescently coupled with the optical waveguide (). Highly reflective broadband mirrors () are provided at the free ends of optical waveguide branches () tangentially connected to the microring resonators. The first and second passive microrings resonators provide an optical feedback to the laser gain section and allow to select the desired wavelength. The laser structure can be implemented according to a III-V/Si technology. 1510610710520620720521621721522622722530630730. A wavelength tunable semiconductor laser comprising a laser gain section ( , ,) , the laser gain section being optically coupled to an optical waveguide ( , ,) having a first end ( , ,) and a second end ( , ,) , a first passive microring resonator ( , ,) being arranged between said first end and said laser gain section , characterized in that:{'b': 540', '640', '740', '541', '641', '741, 'the first passive microring resonator is extended by a first optical waveguide branch (,,) tangentially connected thereto according to a whistle geometry, the first optical waveguide branch being provided with a first highly reflective broadband mirror (,,) at its free end,'}{'b': 523', '623', '723', '524', '624', '724, 'the optical waveguide is provided with a first mirror (,,) at its first end and with a second mirror (,,) at its second end;'}the first microring resonator is evanescently coupled with the optical waveguide on a first side of the laser gain section to provide an optical feedback to the laser gain section.2580680780. A wavelength tunable semiconductor laser according to claim 1 , characterized in that the first passive microring resonator is provided with a ...

HEATER-ON-HEATSPREADER

Systems and methods are described herein to thermally regulate laser diodes. During operation, the structure of a laser diode may generate heat, which will affect the stability and accuracy of the output wavelength of the laser diode. During an OFF stage, the structure of the laser diode will then lose heat, creating a thermal gradient as the laser diode is switched between operation and an OFF state. The systems and methods provide constant average heat and a stable thermal gradient by integrating a laser diode power-coupled supply and a heater onto a heatspreader, such that the output wavelength of a coupled laser diode may be stabilized. 1. A heater-on-heatspreader system comprising:a heatspreader;a first power-coupled source integrated into the heatspreader and in electrical connection and thermal connection with a heat generating device;a second power-coupled source integrated into the heatspreader; anda thermal generator in electrical connection with the second power-coupled source and integrated into the heatspreader;wherein:the first power-coupled source and the second power-coupled source are cycled in an OFF state and an ON state such that an average thermal transfer to the heat spreading device remains constant.2. The system of claim 1 , wherein the thermal generator is a resistive heater.3. The system of claim 2 , wherein the heat generating device is a laser diode operating at a single wavelength.4. The system of claim 3 , wherein a first thermal output from the laser diode during an ON state of the laser diode is compensated by a second thermal output from the thermal generator during an OFF state of the laser diode.5. The system of claim 4 , wherein the laser diode is preheated by the thermal generator.6. The system of claim 5 , wherein an output wavelength of the laser diode is tuned to a target wavelength by adjusting the second thermal output.7. The system of claim 6 , wherein the heater-on-heatspreader is mounted to a temperature control plate ...