ЛАЗЕР С ВЕРТИКАЛЬНЫМ РЕЗОНАТОРОМ И ВЫВОДОМ ИЗЛУЧЕНИЯ ЧЕРЕЗ ПОВЕРХНОСТЬ, НАБОР ЛАЗЕРОВ И СПОСОБ ПОВЫШЕНИЯ КПД ЛАЗЕРНОГО УСТРОЙСТВА

Изобретение относится к лазерной технике. В устройстве и способе генерирования мощного лазерного излучения геометрия лазерного резонатора определяет основную пространственную или поперечную резонаторную моду. Внутри резонатора расположена усиливающая среда, и источник энергии активизирует усиливающую среду в пределах первого объема. Это вызывает спонтанное и вынужденное испускание энергии, распространяющееся в усиливающей среде в направлении, поперечном основной резонаторной моде. Это поперечное испускание энергии, в свою очередь, накачивает второй объем усиливающей среды, расположенный вокруг первого объема. Когда интенсивность испускания достаточно высока, во втором объеме создаются инверсия и усиление. За счет оптимизации геометрии резонатора таким образом, чтобы основная резонаторная мода проходила как через первый, так и через второй объемы, окружая первый накачиваемый объем, поперечно направленная энергия первого объема, которая иначе была бы потеряна, захватывается основным лучом ...

ТВЕРДОТЕЛЬНЫЙ ЛАЗЕРНЫЙ ПРИБОР С ОПТИЧЕСКОЙ НАКАЧКОЙ С САМОРЕГУЛИРУЮЩЕЙСЯ ОПТИКОЙ НАКАЧКИ И УЛУЧШЕННЫМ УСИЛЕНИЕМ

Изобретение относится к лазерной технике. Твердотельный лазерный прибор с оптической накачкой содержит лазерную среду в лазерном резонаторе. Резонатор образован первым зеркалом резонатора, расположенным с первой стороны лазерной среды, и вторым зеркалом резонатора, расположенным со второй стороны, противоположной первой стороне. Первое зеркало резонатора образовано из распределенного брэгговского отражателя, на котором расположена твердотельная лазерная среда. Первые и вторые зеркала резонатора выполнены и расположены с возможностью направлять лазерное излучение из резонатора по двум различным прямым путям через лазерную среду. Лазерный диод накачки выполнен и расположен с возможностью оптически накачивать упомянутую лазерную среду путем отражения излучения накачки на отражающем излучение накачки зеркале. Отражающее излучение накачки зеркало расположено на второй стороне и выполнено с возможностью отражать излучение накачки к лазерной среде. Отражающее излучение накачки зеркало и второе ...

ПОЛУПРОВОДНИКОВЫЙ ЛАЗЕР С ШИРОКИМ ПЕРИОДИЧЕСКИ СЕКЦИОНИРОВАННЫМ ПОЛОСКОВЫМ КОНТАКТОМ

Изобретение относится к области лазерной техники, в частности к системам диодной накачки, к медицинским лазерам, а также к лазерным системам, используемым в информатике, оргтехнике и индустрии развлечений. Полупроводниковый лазер содержит высокоотражающее зеркало, активный элемент, снабженный периодически секционированным электродом, коллимирующую линзу и волноводно-решеточное зеркало, установленное под углом θ к оси активного элемента. Высокоотражающее зеркало выполнено в виде многослойного диэлектрического покрытия, нанесенного на торец активного элемента. Волноводно-решеточное зеркало выполнено либо в виде пленочного волновода, нанесенного на гофрированную подложку, либо в виде гофрированного волноводного слоя, нанесенного на плоскую подложку, либо в виде слоя диэлектрика с периодической модуляцией показателя преломления, нанесенного на плоскую диэлектрическую подложку. Различные модификации полупроводниковых лазеров содержат активный элемент в виде линейки диодных лазеров, либо в виде ...

Перестраиваемый диодный лазер с внешним резонатором

Laserdiodenvorrichtung für Ramanspektroskopie

Light-emitting semiconductor array, has pumping lasers directing beams parallel to common plane, to excite surface-emitting semiconductor lasers

The array comprises surface-emitting semiconductor lasers (1) arranged in a plane, with an external resonator. Each pumping laser (2) emits a beam directed laterally, for optical pumping of the surface-emitting semiconductor lasers. Each beam is directed parallel to the common plane.

Vorrichtung zur Wellenleiterkopplung, Vorrichtung zur Strahlbündelung, und Gerät für optische Platten

VORRICHTUNG FÜR OPTISCHE ABBILDUNG UND MESSUNG

VORRICHTUNG FUER OPTISCHEN WELLENLAENGENMULTIPLEXER.

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.

INTEGRIERTER OPTISCHER BAUTEIL ZUR KOPPLUNG

Laser mit externem Resonator und verbessertem Einzelmodenbetrieb

SPEKTROSKOPISCHES KATHETERSYSTEM MIT BREIT ABSTIMMBARER QUELLE

HALBLEITERLASERMODUL MIT VERBESSERTER WELLENLÄNGENSTABILITÄT

Wellenlängenmesser und zugehöriges Verfahren

Allgemein werden ein Wellenlängenmesser, ein zugehöriges Verfahren und ein zugehöriges System beschrieben. Bei einem Beispiel weist eine Vorrichtung Folgendes auf: eine Fotodiode zum Empfangen eines optischen Signals und zum Erzeugen eines Fotostroms beim Empfangen des optischen Signals, wobei die Fotodiode eine Absorptionskante hat, die im Wesentlichen auf ein Band von Wellenlängen ausgerichtet ist, wobei sich die Absorptionskante zu längeren Wellenlängen hin verschiebt, wenn eine Sperrvorspannung an die Fotodiode angelegt wird; und mit der Fotodiode verbundene Steuerelektronik zum Anlegen mindestens einer ersten Sperrvorspannung und einer zweiten Sperrvorspannung an die Fotodiode, wobei ein Verhältnis eines ersten Messwerts des Fotostroms bei der ersten Sperrvorspannung zu einem zweiten Messwert des Fotostroms bei der zweiten Sperrvorspannung Informationen zu der Wellenlänge des optischen Signals liefert.

Oberflächenemittierendes Halbleiterlaser-Bauelement und optische Projektionsvorrichtung mit solch einem oberflächenemittierenden Halbleiterlaser-Bauelement

Es wird ein oberflächenemittierendes Halbleiterlaser-Bauelement offenbart, mit DOLLAR A - einem Resonator (3, 9), DOLLAR A - einem Halbleiterkörper (5), der eine zur Strahlungserzeugung vorgesehene Schichtenfolge (4) umfasst, DOLLAR A - einem transparenten, frequenzselektiven Wärmeleitelement (6), das sich mit einer Strahlungsdurchtrittsfläche (5a) des Halbleiterkörpers (5) in thermischem Kontakt befindet, und DOLLAR A - einem optischen Bandpassfilter (8), das geeignet ist, vorgebbare Resonatormoden zu unterdrücken. DOLLAR A Das beschriebene oberflächenemittierende Halbleiterlaser-Bauelement eignet sich besonders gut für die Verwendung in einer optischen Projektionsvorrichtung.

Moduseinrasthalbleiterlasersystem mit externem Resonator

Die vorliegende Erfindung betrifft ein optisches System mit einem Resonator, das eine lichtemittierende Halbleitervorrichtung und eine optische Faser aufweist, die ein erstes Ende hat, das mit der lichtemittierenden Halbleitervorrichtung gekoppelt ist, wobei der Resonator eine Resonatorlänge hat, die zwischen einer ersten Fläche der lichtemittierenden Halbleitervorrichtung und einem zweiten Ende der optischen Faser begrenzt ist, worin eine Länge der optischen Faser derart ausgelegt ist, dass eine Moduseinrastoszillationsfrequenz nicht größer als 1 GHz beträgt.

Optisch pumpbare oberflächenemittierende Halbleiterlaservorrichtung

Oberflächenemittierende Halbleiterlaservorrichtung mit einem mittels einer Pumpstrahlungsquelle optisch pumpbaren Vertikalemitter (20), der eine strahlungserzeugende Schicht (14) und einen externen Resonator aufweist, dadurch gekennzeichnet, daß zumindest eine Modulationsstrahlungsquelle (30) zur Modulation der Ausgangsleistung der oberflächenemittierenden Halbleiterlaservorrichtung vorgesehen ist, die eine kantenemittierende Halbleiterstruktur (15) mit einer strahlungserzeugenden aktiven Schicht umfaßt, und die so angeordnet ist, daß sie im Betrieb Strahlung emittiert, die in die strahlungserzeugende aktive Schicht (14) des Vertikalemitters (20) eingekoppelt wird und dort eine mittels der Pumpstrahlungsquelle erzeugte Besetzungsinversion zumindest teilweise abbaut.

Abstimmbares Lichtquellenmodul

Durch die Erfindung ist ein abstimmbares Lichtquellenmodul mit einem Lichtemissions-Halbleiterbauteil, einem abstimmbaren Fabry-Perot-Resonator zum Filtern des von diesem emittierten Lichts und einem Reflektor geschaffen. Durch den Reflektor läuft das vom Fabry-Perot-Resonator gefilterte Licht erneut durch diesen, und es kehrt dann zum Lichtemissions-Halbleiterbauteil zurück.

Diodenlaser mit einem externen frequenzselektiven Element

Die vorliegende Erfindung betrifft einen rauscharmen, wellenlängenstabilisierten Diodenlaser mit kollimierter Strahlung und geringem Strahldurchmesser. Es ist Aufgabe der vorliegenden Erfindung, inen Diodenlaser mit Wellenlängenstabilisierung und vergeben, der einen geringen Abstand des Volumen-Bragg-Gitters zur Emissionsfläche, einen kleinen vertikalen Durchmesser des kollimierten Strahls und außerdem einen Ausgleich von Fertigungstoleranzen bei der Form des Gitters und der Linse ermöglicht. Erfindungsgemäß weist der Diodenlaser ein externes frequenzselektives Element (14) zur Wellenlängenstabilisierung der Laserstrahlung auf, wobei das externe frequenzselektive Element (14) eine der Austrittsfacette (12) zugewandte Eintrittsfläche (16) und eine der Austrittsfacette (12) abgewandte Austrittsfläche (18) aufweist und durch ein Volumen-Bragg-Gitter ausgebildet ist; und wobei das externe frequenzselektive Element (14) derart ausgebildet ist, dass die Divergenz der aus der Austrittsfacette ...

LICHTQUELLE MIT VARIABLER WELLENLÄNGE

OPTISCH GEPUMPTER PASSIV MODENGEKOPPELTER OBERFLÄCHENEMITTIERENDER HALBLEITERLASER MIT EXTERNEM RESONATOR

Oberflächenemittierender Halbleiterlaser und Verfahren zu dessen Herstellung

Oberflächenemittierender Halbleiterlaser mit – einem Halbleiterchip (1), der ein Substrat (2) und eine auf dem Substrat (2) aufgewachsene Halbleiterschichtenfolge (19), die eine strahlungsemittierende aktive Zone (12) umfasst, enthält, und – einem externen Resonatorspiegel (5), dadurch gekennzeichnet, dass – das Substrat (2) eine Ausnehmung (3) aufweist und die emittierte Strahlung (6) durch die Ausnehmung (3) ausgekoppelt wird, und – zum optischen Pumpen des oberflächenemittierenden Halbleiterlasers eine außerhalb des Halbleiterchips (1) angeordnete Pumpstrahlungsquelle (8) vorgesehen ist, wobei die von der Pumpstrahlungsquelle (8) emittierte Pumpstrahlung (9) durch die Ausnehmung (3) des Substrats (9) in die aktive Zone (12) eingestrahlt wird.

Optical source

Tunable pumping light source for optical amplifiers

Multi-wavelengh diode laser array

APPARATUS FOR OPTICAL WAVELENGTH DIVISION MULTIPLEXING

A Laser System

A laser system has an input waveguide 4 which receives an optical input signal from an optical amplifier 3. Partial reflecting means 5 for example, a Bragg grating, receives an optical input signal from the input waveguide and reflects a portion of the optical input signal back along the input waveguide. The reflecting means 5 and the optical amplifier 3 define a resonant cavity. A reflection photodetector means 30 detects light reflected back by the partial reflecting means 5 and supplies an electrical output signal indicative of the reflected light. Phase modulation means modulates the phase of the optical input signal. Control means controls the phase modulation means in dependence on the electrical output signal from the reflection photodetector means in order to provide a stabilised optical output signal. Preferably, a transmission photodetector 6 detetcts the optical output signal and supplies an electrical output signal indicative of the output signal.

Tunable semiconductor laser

A tunable distributed Bragg reflector (DBR) semiconductor laser 100 is disclosed. In particular a DBR laser 100 with a branched optical waveguide within which a plurality of differently shaped lasing cavities is formed. An optical waveguide 118 is provided with an optical reflector 112 capable of providing a comb-like output. The waveguide 118 is optically coupled to at least two branch waveguides 108, 114 each provided with a tunable optical reflector 116 such as a chirped grating. The tunable optical reflectors 116 are tuned to different wavelength ranges. In operation, a laser cavity formed between the optical reflector 112 and at least one of the tunable optical reflectors 116 emits light at a wavelength within either of the tuned wavelengths of the branches 108, 114.

Apparatus for optical wavelength division multiplexing

PCT No. PCT/GB88/00191 Sec. 371 Date Nov. 9, 1988 Sec. 102(e) Date Nov. 9, 1988 PCT Filed Mar. 11, 1988 PCT Pub. No. WO88/07216 PCT Pub. Date Sep. 22, 1988.Apparatus of the type comprising an optical assembly and reflection grating-for collimating light emitted by a laser and for refocussing the same onto an output waveguide. The waveguide is modified to enhance reflection of the refocussed light, which in turn dominates the resonant response of the laser. Laser resonance thus depends on geometrical factors-the relative positions of laser and waveguide and the dispersion properties of the assembly. Wavelength selectivity is improved by confining reflection to the core of the waveguide e.g. by using an embedded reflector, or further still by using an etalon pair. The laser may be used in conjunction with other lasers and/or detectors, or with retroreflectors. A multi-laser input multiplexer and single channel drop-and-add devices are described.

Improvements to windows / doors

Optical Amplifiers

Improvements to windows / doors

WAVELENGTHTUNABLE SOURCE OF LIGHT

OPTICAL TRANSVERSE ELECTROMAGNETIC WAVE DEVICE, COHERENT SOURCE OF LIGHT AND OPTICAL EQUIPMENT, WHICH THE OPTICAL TRANSVERSE ELECTROMAGNETIC WAVE DEVICE MENTIONED USING

LASER SYSTEM WITH EXTERNAL OPTICAL FEEDBACK AND USE OF SUCH A SYSTEM IN THE GRAPHICS INDUSTRY

IMPROVEMENTS OF OPTICAL SEMICONDUCTOR DEVICES WITH VERTICAL RESONATOR

DIODE LASER WITH A SATURABLE BRAGG REFEKTORSPIEGEL

TUNABLE DEMULTIPLEXER AND TUNABLE LASER WITH OPTICAL DEFLECTOR

MONO MODE TUNABLE ONE SOURCE OF LASER

SURFACE-EMITTING LASER APPARATUS WITH EXTERNAL RESONATOR

OPTICAL ONE MULTIPLEXIERUNG.

TUNABLE LASER AND PROCEDURE FOR ITS VOTE

PROCEDURE FOR THE SICHERSTELLUNG OF A OF FASHION LEAPS FREE VOTE OF THE RESONANT FREQUENCY AND THE Q-FACTOR OF AN OPTICAL RESONATOR AS WELL AS DEVICE FOR THE EXECUTION OF THE PROCEDURE

CONTINUOUS REMOTE UV LASER SYSTEM WITH TWO ACTIVE RESONATORS

MORE RAMANVERSTÄRKER AND PROCEDURES FOR THE SUGGESTION OF A RAMANVERSTÄRKERS

WAVELENGTHTUNABLE SOURCE OF LIGHT

OPTICAL TRANSVERSE ELECTROMAGNETIC WAVE DEVICE, COHERENT SOURCE OF LIGHT AND OPTICAL EQUIPMENT, WHICH THE OPTICAL TRANSVERSE ELECTROMAGNETIC WAVE DEVICE MENTIONED USING

OPTICAL TRANSVERSE ELECTROMAGNETIC WAVE DEVICE, COHERENT SOURCE OF LIGHT AND OPTICAL EQUIPMENT, WHICH THE OPTICAL TRANSVERSE ELECTROMAGNETIC WAVE DEVICE MENTIONED USING

WAVELENGTHTUNABLE SOURCE OF LIGHT

WAVELENGTHTUNABLE SOURCE OF LIGHT

WAVELENGTHTUNABLE SOURCE OF LIGHT

OPTICAL TRANSVERSE ELECTROMAGNETIC WAVE DEVICE, COHERENT SOURCE OF LIGHT AND OPTICAL EQUIPMENT, WHICH THE OPTICAL TRANSVERSE ELECTROMAGNETIC WAVE DEVICE MENTIONED USING

WAVELENGTHTUNABLE SOURCE OF LIGHT

WAVELENGTHTUNABLE SOURCE OF LIGHT

OPTICAL TRANSVERSE ELECTROMAGNETIC WAVE DEVICE, COHERENT SOURCE OF LIGHT AND OPTICAL EQUIPMENT, WHICH THE OPTICAL TRANSVERSE ELECTROMAGNETIC WAVE DEVICE MENTIONED USING

OPTICAL TRANSVERSE ELECTROMAGNETIC WAVE DEVICE, COHERENT SOURCE OF LIGHT AND OPTICAL EQUIPMENT, WHICH THE OPTICAL TRANSVERSE ELECTROMAGNETIC WAVE DEVICE MENTIONED USING

WAVELENGTHTUNABLE SOURCE OF LIGHT

OPTICAL TRANSVERSE ELECTROMAGNETIC WAVE DEVICE, COHERENT SOURCE OF LIGHT AND OPTICAL EQUIPMENT, WHICH THE OPTICAL TRANSVERSE ELECTROMAGNETIC WAVE DEVICE MENTIONED USING

OPTICAL TRANSVERSE ELECTROMAGNETIC WAVE DEVICE, COHERENT SOURCE OF LIGHT AND OPTICAL EQUIPMENT, WHICH THE OPTICAL TRANSVERSE ELECTROMAGNETIC WAVE DEVICE MENTIONED USING

OPTICAL TRANSVERSE ELECTROMAGNETIC WAVE DEVICE, COHERENT SOURCE OF LIGHT AND OPTICAL EQUIPMENT, WHICH THE OPTICAL TRANSVERSE ELECTROMAGNETIC WAVE DEVICE MENTIONED USING

WAVELENGTHTUNABLE SOURCE OF LIGHT

OPTICAL TRANSVERSE ELECTROMAGNETIC WAVE DEVICE, COHERENT SOURCE OF LIGHT AND OPTICAL EQUIPMENT, WHICH THE OPTICAL TRANSVERSE ELECTROMAGNETIC WAVE DEVICE MENTIONED USING

WAVELENGTHTUNABLE SOURCE OF LIGHT

OPTICAL TRANSVERSE ELECTROMAGNETIC WAVE DEVICE, COHERENT SOURCE OF LIGHT AND OPTICAL EQUIPMENT, WHICH THE OPTICAL TRANSVERSE ELECTROMAGNETIC WAVE DEVICE MENTIONED USING

OPTICAL TRANSVERSE ELECTROMAGNETIC WAVE DEVICE, COHERENT SOURCE OF LIGHT AND OPTICAL EQUIPMENT, WHICH THE OPTICAL TRANSVERSE ELECTROMAGNETIC WAVE DEVICE MENTIONED USING

OPTICAL TRANSVERSE ELECTROMAGNETIC WAVE DEVICE, COHERENT SOURCE OF LIGHT AND OPTICAL EQUIPMENT, WHICH THE OPTICAL TRANSVERSE ELECTROMAGNETIC WAVE DEVICE MENTIONED USING

WAVELENGTHTUNABLE SOURCE OF LIGHT

OPTICAL TRANSVERSE ELECTROMAGNETIC WAVE DEVICE, COHERENT SOURCE OF LIGHT AND OPTICAL EQUIPMENT, WHICH THE OPTICAL TRANSVERSE ELECTROMAGNETIC WAVE DEVICE MENTIONED USING

Optical waveguide device, coherent light source using same and optical apparatus having same

Wavelength control of an external-cavity tuneable laser

FIBER OPTICS SYSTEM

Measuring device for determining tissue alcohol concentration

... - 13 Abstract The present invention relates to a measuring-device for determining the concentration of body tissue contents by reflection spectroscopy. In order, among other things, to increase the device's functional reliability when subjected to shocks, 5 the inventive measuring-device comprises: a diode laser (1) with at least one laser diode (Ia, I b); and a waveguide structure (2), with an external resonator (2a, 2b) for each laser diode (I a, I b). Each external resonator (2a, 2b) has a wavelength-selection element. The radiation produced by a laser diode (Ia, I b) can be coupled into the waveguide structure (2) and the corresponding resonator (2a, 2b), and can be coupled 10 out of the resonator (2a, 2b) and the waveguide structure (2) again. The present invention also relates to a corresponding method and to a vehicle equipped with the inventive measuring-device. (Figure 1) 06/09/11,19396 speci, 13 ...

External cavity laser with optically switched tuning mechanism

METHOD FOR ASCERTAINING MODE HOPPING FREE TUNING OF RESONANCE FREQUENCY AND THE Q-VALUE OF AN OPTICAL RESONATOR AND A DEVICE FOR CARRYING OUT THE METHOD

Frequency-narrowed high power diode laser system with external cavity

Tunable laser with microactuator

A TUNEABLE LASER AND A METHOD OF TUNING THE SAME

A tuneable laser that includes a gain section (11; 34) and a tuneable wavelength-selective filter (12; 27). The invention is characterised in that a reflection filter in the form of an external reflector (13) is adapted to give a number of fixed reflection maxima, where each maximum corresponds to a given wavelength. The reflection filter is adapted to coact with the tuneable filter and the laser is adapted to be tuned to lase at any selected one of said wavelengths, by tuning the tuneable filter (12; 27). The invention also relates to a method.

PROCESS AND APPARATUS FOR A WAVELENGTH TUNING SOURCE

NON-SPHERICAL WHISPERING-GALLERY-MODE MICROACTIVITY

Devices based on a non-spherical whispering-gallery-mode optical resonator.

QUANTUM DOT TUNABLE EXTERNAL CAVITY LASERS (QD-TEC LASERS)

A laser system includes a laser diode with a low dimensional nanostructure, such as quantum dots or quantum wires, for emitting light over a wide range of wavelengths. An external cavity is used to generate laser light at a wavelength selected by a wavelength--selective element. The system provides a compact and efficient laser tunable over a wide range of wavelengths.

ALTERNATING SEQUENTIAL HALF DUPLEX COMMUNICATION SYSTEM

ALTERNATING SEQUENTIAL HALF DUPLEX COMMUNICATION SYSTEM A message communication system employing one or more centralized communication stations transferring messages through Earth orbit repeater satellites to or from mobile terminals with at least one central communication station having a first transceiver for transmitting a first communication signal to one or more mobile terminals and at least one mobile terminal having a second transceiver for receiving the first communication signal and demodulating it, and for transmitting at a predetermined duty cycle of the second transceiver, a second communication signal to at least one of the central communication stations. The preferred duty cycle over which the second communication signal is transmitted is about fifty percent of the second transceiver duty cycle. The communication system uses Time Division Multiplexed (TDM) communication signals using number of channels as designated address channels with the remainder being used for data transfer ...

SEMICONDUCTEUR DEVICE ASSEMBLY

An external cavity laser assembly in which the laser chip is within a hermetically sealed package and the external cavity is outside the hermetic package. A collimating lens in a screw threaded mounting is disposed outside the hermetic package, the screw thread permitting focussing. The cavity is tuned by rotation and translation of a grating, the position of which is electrically controlled via piezoelectric stacks. Thermal expansion of the stacks is compensated by mounting the grating on a rod of suitable material (e.g. ceramic) which also serves to reduce the cavity length whilst allowing maximum piezoextension. In a second embodiment the assembly is a tunable laser amplifier, with a grating being driven in a similar manner to provide the tuning.

SELF-ADAPTED FILTERS FOR SHARPENING LASER EMISSION

L'invention concerne une source de rayonnement lumineux cohérent de type laser comportant une cavité résonante et un milieu amplificateur placé dans la cavité résonante, caractérisée en ce qu'un matériau photosensible dynamique est placé dans la cavité résonnante pour former un filtre spectral et/ou spatial auto-adaptable.

MEASUREMENT SYSTEM AND TEMPERATURE AND/OR SHAPE CHANGE SENSOR USING BRILLOUIN BACK-REFLECTION ANALYSIS

Système de mesure par analyse de rétroréflexion Brillouin, comprenant un dispositif d'émission laser (10) configuré pour émettre une onde incidente (v0) et une onde de référence (v0-vB), l'onde incidente présentant une fréquence incidente (v0) et l'onde de référence présentant une fréquence de référence (v0-vB), la fréquence de référence (v0-vB) étant décalée de la fréquence incidente (v0) d'une valeur prédéterminée (vB). Le système est configuré pour : - projeter l'onde incidente (v0) dans la fibre optique (25); - recevoir en retour une onde rétroréfléchie (v0-vS); - générer une onde composite (v0-S,0-B) combinant l'onde rétroréfléchie (v0-vS) et l'onde de référence (v0-vB); et - déterminer au moins une propriété relative à la fibre par analyse d'un spectre Brillouin de l'onde composite (v0-S,0-B). Avantageusement, l'onde incidente et l'onde de référence proviennent d'une source laser (12) bi-fréquence à cavité verticale émettant par la surface, faisant partie du dispositif d'émission ...

TUNABLE LASER SOURCE, AND METHOD FOR PREVENTING OCCURRENCE OF MODE HOPPING PHENOMENON IN TUNABLE LASER SOURCE

A tunable laser source for continually changing the wavelength of output light by means of changing the length of an external cavity of an external cavity-type semiconductor laser light source section includes laser diode current control section 7, 8 for controlling a drive current supplied to a laser diode 1 as section for changing the length of the external cavity for preventing occurrence of mode hopping which arises as a result of continual changes in the wavelength of output light.

PHASE-CONTROL IN AN EXTERNAL-CAVITY TUNEABLE LASER

The present invention relates to a single-mode external-cavity tuneable laser including a gain medium, a tuneable element and a channel allocation grid element. The channel allocation grid element is preferably a FP etalon, which is structured and configured to define a plurality of equally spaced transmission peaks corresponding to the ITU channel grid, e.g., 200, 100, 50 or 25 GHz. The tuneable element, preferably a tuneable mirror, serves as the coarse tuning element that discriminates between the peaks of the grid etalon. The tuneable laser of the invention has a relatively short cavity length of not more than 15 mm, preferably not larger than 12 mm. It has been found that the FP etalon introduces a phase non-linearity in the external cavity, which induces a compression of the cavity modes, i.e., a reduction in the cavity mode spacing, in correspondence to the etalon transmission peaks. Mode compression increases with the decrease of the FWHM bandwidth of the grid FP etalon, hereafter ...

MODE-LOCKING SEMICONDUCTOR DISK LASER (SDL)

The present invention describes a mode locking semiconductor disk laser (SDL). The laser comprises a resonator terminated by first and second mirrors (6,7) and folded by a third mirror. The third mirror comprising a semiconductor disk laser (8) suitable for generating a resonator field comprising a predetermined central wavelength AO while the second mirror comprising an intensity saturable mirror (7) suitable for mode locking the resonator field at the predetermined wavelength. The reflectivity of the of the resonator at the central wavelength AO is reduced by shifting the reflectivity profiles of the first and or second mirrors to wavelength shorter than the predetermined wavelength so as to suppress gain at wavelengths longer than the central wavelength AO. By mismatching the reflectivity profile (32) of the second mirror (7) to that of the desired output wavelength (3) provides a stable mode locked laser with significantly reduced noise. The SDL may comprise a DBR with a reflectivity ...

IMPROVED SELF MODE-LOCKING SEMICONDUCTOR DISK LASER (SDL)

A self mode locking laser and corresponding method is described. The laser comprises a resonator (2) terminated by first (3) and second (4) mirrors and folded by a third mirror (5). The third mirror comprises a reflector (15) surmounted by a multilayer semiconductor gain medium (16) that includes at least one quantum well layer and an optical Kerr lensing layer (20). A perturbator is also included that provides a means to induce a perturbation on an intensity of one or more cavity modes of the resonator. The pertubator is employed to induce a small perturbation on the intensity of the cavity modes of the resonator which is sufficient for the optical Kerr lensing layer to induce mode locking on the output field. The second mirror (4) comprises an intensity saturable mirror that provides a means for reducing the pulse widths of the generated output field e.g. to around 100 fs. A diamond heat spreader (20) is attached to the top of the half VCSEL gain medium (13) for improved cooling as well ...

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 ...

FIBER OPTICS SYSTEM

... 2084077 9120113 PCTABS00009 Means (30) for continuous waveband tuning of a laser (2) are disclosed, along with means (34) for relating such tuning to a reference wavelength, by maintaining any desired offset (35) from that reference wavelength. Multichannel fiber optics communications networks employing the above means (30) are disclosed, said networks being self organizing in terms of the wavelengths of their channels.

MULTI-STRIPE ARRAY GRATING INTEGRATED CAVITY LASER

CONTINUOUSLY TUNEABLE LASER

A multi-line continuous wideband tunable laser (1) utilizes a symmetric or asymmetric grating (5) and a plurality of optical fibers (3), each of which forms a part of a respective laser cavity optical axis. By simultaneously altering both the periodicity of the intersections of the grating (5) with the plurality of optical axes established by the plurality of optical fibers (3) and the effective cavity length of each laser (1), a single-line spectral output is achieved at any desired point in the operating band.

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.

Optically pumped, surface-emitting semiconductor laser and method for producing the same

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 ...

COMPONENT OF COUPLING CARRIED out IN OPTICS INTEGREE, READY TO ADAPT a SOURCELUMINEUSE HAS an ELEMENT Of OPTICS GUIDEE AND LASER OF POWER COMPRISING IT

Measuring Instrument for Determining the Tissue Alcohol Concentration

A measuring instrument for determining the concentration of components in the body tissue by reflection spectroscopy is disclosed. In order, inter alia, to increase the functional reliability in the case of vibrations, the measuring instrument includes a diode laser with at least one laser diode and a waveguide structure, which has an external resonator, with a wavelength selective element, for each laser diode. In the process, the radiation generated by a laser diode is coupleable into the waveguide structure and the corresponding resonator and once again decoupleable from the resonator and the waveguide structure. Moreover, a corresponding method and a motor vehicle equipped therewith are disclosed.

Multi-wavelength high output laser source assembly with precision output beam

A laser source assembly ( 210 ) for generating an assembly output beam ( 212 ) includes a first laser source ( 218 A), a second laser source ( 218 B), and a dispersive beam combiner ( 222 ). The first laser source ( 218 A) emits a first beam ( 220 A) having a first center wavelength, and the second laser source ( 218 B) emits a second beam ( 220 B) having a second center wavelength that is different than the first center wavelength. The dispersive beam combiner ( 222 ) includes a common area 224 that combines the first beam ( 220 A) and the second beam ( 220 B) to provide the assembly output beam ( 212 ). The first beam ( 220 A) impinges on the common area ( 224 ) at a first beam angle ( 226 A), and the second beam ( 220 B) impinges on the common area ( 224 ) at a second beam angle ( 226 B) that is different than the first beam angle ( 226 A). Further, the beams ( 220 A) ( 220 B) that exit from the dispersive beam combiner ( 222 ) are substantially coaxial, are fully overlapping, and are co-propagating.

Actively Mode Locked Laser Swept Source for OCT Medical Imaging

An optical coherence analysis system uses a laser swept source that is constrained to operate in a mode locked condition. This is accomplished by synchronously changing the laser cavity's gain and/or phase based on the round trip travel time of light in the cavity. This improves high speed tuning by taking advantage of frequency shifting mechanisms within the cavity and avoids chaotic laser behavior.

Diode laser

A diode laser is provided with wavelength stabilization and vertical collimation of the emitted radiation, which allows a small distance of the volume Bragg grating from the emitting surface, a small vertical diameter of the collimated beam and also compensation for manufacturing tolerances affecting the shape of the grating and the lens. The diode laser comprises an external frequency-selective element for wavelength stabilization of the laser radiation, wherein the external frequency-selective element comprises an entry surface facing the exit facet and an exit surface facing away from the exit facet and is designed as a volume Bragg grating; and wherein the external frequency-selective element is designed in such a manner that the divergence of the radiation emitting from the exit facet is reduced during passage through the external frequency-selective element.

Laser characterization system and process

A system and process for automatically characterizing a plurality of external cavity semiconductor laser chips on a semiconductor laser bar separated from a semiconductor wafer. The system includes a diffraction grating and a steering mirror mounted on a rotary stage for rotating the diffraction grating through a range of diffraction angles. A laser bar positioning stage for automatically aligning each laser chip in a laser bar with the diffraction grating. Reflecting a laser beam emitted from a laser chip in a laser bar with diffraction grating and steering mirror to the laser analyzer. Automatically rotating the diffraction grating through a range of diffraction angles relative to the laser beam and automatically characterizing the laser optical properties such as spectra, power, or spatial modes with the laser analyzer at each diffraction angle.

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.

Small packaged tunable laser assembly

A tunable laser configured in a small package coupled to a printed circuit board. The tunable laser includes a housing with a volume formed by exterior walls. An electrical input interface is positioned at the first end of the housing. An optical output interface is positioned at the second end of the housing and configured to transmit a continuous wave optical beam. A beam splitter and photodiode is disposed in the path of the laser beam for determining the emitted intensity of the laser beam, and an optical isolator is positioned downstream of the beam splitter to prevent the incoming light from the beam splitter from reflecting back though the beam splitter and into the cavity of the laser.

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.

Laser architectures

Disclosed herein are architectures for VCSEL systems. By using high power IR VCSEL element(s), a bulk doubling material can be used to double the IR light and generate visible light (red, green, blue, or UV light) in a cavity, in either continuous wave (CW) or pulsed mode. The reflectivity of the output distributed Bragg reflector (DBR) of these VCSELs can be designed to increase the power in the cavity, rather than the power in the VCSEL laser. By enabling the use of a bulk doubling material in the cavity and directly doubling the VCSEL the device can be inexpensive, simpler, high efficiency, better reliability, and vastly improved manufacturing and alignment tolerances. There are a number of cavity architectures that can be used to double the IR light from the VCSEL(s). The VCSEL(s) can be single elements, or arrays with high intensity elements.

EXTERNAL CAVITY LASER ARRAY SYSTEM AND WDM OPTICAL SYSTEM INCLUDING SAME

An external cavity laser array system may be used in a WDM optical system, such as a WDM-PON, for transmitting optical signals at multiple channel wavelengths. The system generally includes a plurality of laser emitters (e.g., gain chips) optically coupled to and separated from respective exit reflectors (e.g., tunable narrow-band reflectors), thereby forming an array of external cavity lasers with extended lasing cavities. The exit reflectors may be distributed Bragg reflectors (DBRs) located in the waveguides in an arrayed waveguide grating (AWG). The laser emitters emit a range of wavelengths including multiple channel wavelengths and the DBRs reflect a subset of channel wavelengths including at least a channel wavelength associated with the laser emitter such that lasing occurs at the subset of channel wavelengths. The AWG then filters the emitted laser light at the associated channel wavelengths. 1. An external cavity laser array system comprising:a plurality of laser emitters, each of the laser emitters including a gain region for emitting light across a range of wavelengths and a back reflector located at one end thereof; andan arrayed waveguide grating (AWG) including a plurality of input ports optically coupled to the laser emitters, respectively, an output port, and a plurality of optical waveguides extending from the input ports, respectively, to the output port, wherein the optical waveguides include distributed Bragg reflector (DBR) gratings, respectively, such that extended lasing cavities are formed between the back reflectors of the laser emitters and the DBR gratings, respectively.2. The external cavity laser array system of wherein the laser emitters include reflective-semiconductor-optical-amplifiers (R-SOAs).3. The external cavity laser array system of further comprising an optical assembly for optically coupling the emitted light into the respective waveguides of the AWG.4. The external cavity laser array system of wherein each of the DBR ...

Method and Apparatus for the Line Narrowing of Diode Lasers

A system for narrowing the spectral output of diode lasers through the use of dielectric stacks in the laser cavity comprising an alternating sequence of layers of dielectric material and air, which dielectric stacks are fabricated through the controlled laser ablation of the dielectric material.

Tunable Pumping Light Source for Optical Amplifiers

A tunable external cavity laser for use as a pump laser in an optical amplifier such as a Raman amplifier or erbium doped fibre amplifier comprising a semiconductor gain device ( 12 ) operable to provide light amplification, a diffraction grating ( 18 ) for selecting the wavelength of operation of the laser and a MEMs actuator for changing the selected wavelength. A plurality of gain devices can be coupled together to improve the bandwidth or gain of the optical amplifier.

Laser Swept Source with Controlled Mode Locking for OCT Medical Imaging

An optical coherence analysis system uses a laser swept source that is constrained to operate in a mode locked condition. This is accomplished by synchronously changing the laser cavity's gain and/or phase based on the round trip travel time of light in the cavity. Many high-speed wavelength swept laser sources emit pulses synchronized with the round trip time of the cavity as part of a nonlinear optical frequency red shifting process. Stable pulsation is associated with smooth tuning and low relative intensity noise. Addition of mode-locking methods to this class of lasers can control and stabilize these lasers to a low clock jitter and RIN state, and in specific cases allow long-to-short wavelength tuning in addition to the usual short-to-long (red shifting). The laser may comprise a SOA ( 410 ), a tunable Fabry-Perot-Filter ( 412 ) as one reflector and an Output coupler ( 405 ) in an optical fiber ( 406 ) to adjust the cavity length.

Light source, and optical coherence tomography module

An optical module includes a light source. The light source can be a swept wavelength light source, and optical module includes a wavemeter. The wavemeter includes a wavemeter tap capable of directing a wavemeter portion of light produced by the light source away from a main beam, a wavelength selective filter arranged to receive the wavemeter portion, a first wavemeter detector arranged to measure a transmitted radiation intensity of radiation transmitted through the filter, and a second wavemeter detector arranged to measure a non-transmitted radiation intensity of radiation not transmitted through but reflected by the filter. In addition, an optical coherence tomography apparatus includes the optical module.

Methods and Apparatus for Swept-Source Optical Coherence Tomography

In one embodiment of the invention, a semiconductor optical amplifier (SOA) in a laser ring is chosen to provide low polarization-dependent gain (PDG) and a booster semiconductor optical amplifier, outside of the ring, is chosen to provide high polarization-dependent gain. The use of a semiconductor optical amplifier with low polarization-dependent gain nearly eliminates variations in the polarization state of the light at the output of the laser, but does not eliminate the intra-sweep variations in the polarization state at the output of the laser, which can degrade the performance of the SS-OCT system. 120-. (canceled)21. An optical imaging system comprising: a first gain element,', 'a tunable filter in optical communication with the first gain element, the tunable filter comprising a drive waveform input, and', 'an output of the tunable laser in optical communication with the tunable filter;, 'a tunable laser comprising'}a first optical coupler in optical communication with the output of the tunable laser; and a source input in optical communication with the first optical coupler,', 'a sample arm in optical communication with the source input, wherein the sample arm is configured to transmit light to an optical probe and receive scattered light acquired by the optical probe, and', 'a first interferometer output., 'a first interferometer comprising'}22. The system of further comprisinga polarization controller in optical communication with the tunable laser output anda second gain element in optical communication with an output of the polarization controller, wherein the second gain element is a booster optical amplifier.23. The system of further comprising a display system comprising a computer in electrical communication with a display claim 21 , wherein the display system is configured to display images using the display claim 21 , the computer claim 21 , and data received thereby claim 21 , wherein the data is generated in response to interference signals ...

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 ...

WAVELENGTH LOCKER USING MULTIPLE FEEDBACK CURVES TO WAVELENGTH LOCK A BEAM

A device may include a first photodetector to generate a first current based on an optical power of an optical beam. The device may include a beam splitter to split a portion of the optical beam into a first beam and a second beam. The device may include a wavelength filter to filter the first beam and the second beam. The wavelength filter may filter the second beam differently than the first beam based on a difference between an optical path length of the first beam and an optical path length of the second beam through the wavelength filter. The device may include second and third photodetectors to respectively receive, after the wavelength filter, the first beam and the second beam and to generate respective second currents. 126-. (canceled)27. A device , comprising:a laser emitter to generate a laser beam to be wavelength locked to a target frequency based on an emission frequency to be measured by the device; 'the laser beam to be wavelength locked based on the first current;', 'a first photodetector to generate a first current based on a first optical power of the laser beam,'}a beam splitter to split a portion of the laser beam into a first beam and a second beam; the patterned etalon to have different optical path lengths for the first beam and the second beam, and', 'the patterned etalon to filter the first beam and the second beam to a second optical power and a third optical power, respectively, based on the different optical path lengths; and, 'a patterned etalon to filter the first beam and the second beam,'} 'a selected current, of the respective second currents, to be used to wavelength lock the laser beam.', 'second and third photodetectors to generate respective second currents,'}28. The device of claim 27 , wherethe beam splitter is further to split the portion of the laser beam into a third beam and a fourth beam, andthe third beam is received by the first photodetector without being filtered by the patterned etalon.29. The device of claim 27 , ...

MEMS BASED SWEPT LASER SOURCE

A MEMS-based swept laser source is formed from two coupled cavities. The first cavity includes a first mirror and a fully reflective moveable minor and operates to tune the output wavelength of the laser. The second cavity is optically coupled to the first cavity and includes an active gain medium, the first mirror and a second mirror. The second cavity further has a length substantially greater than the first cavity such that there are multiple longitudinal modes of the second cavity within a transmission bandwidth of the first cavity output. 1. A swept laser source , comprising:a first cavity formed between a first mirror and a moveable mirror that is fully reflective, the first cavity being operable to select at least one longitudinal mode of the first cavity as a first cavity output;a second cavity optically coupled to the first cavity to receive the first cavity output, the second cavity including an active gain medium operating as an optical amplifier and being formed between the first minor and a second minor, the second cavity having a length substantially greater than the first cavity such that there are multiple longitudinal modes of the second cavity within a transmission bandwidth of the first cavity output, the second cavity producing a laser output including at least one longitudinal mode of the second cavity that has a line width within the first cavity output; anda Micro-Electro-Mechanical Systems (MEMS) actuator coupled to the moveable minor to cause a displacement thereof to select the at least one longitudinal mode of the first cavity for the first cavity output, thereby tuning an output wavelength of the laser output;wherein the first cavity, the second cavity and the MEMS actuator are fabricated on a silicon substrate.2. The swept laser source of claim 1 , wherein the first cavity operates as a notch rejection filter in the optical domain and as a selective notch reflection filter in the presence of the active gain medium in the second cavity to ...

CHIRPED BRAGG GRATING ELEMENTS

Apparatus and methods for altering one or more spectral, spatial, or temporal characteristics of a light-emitting device are disclosed. Generally, such apparatus may include a volume Bragg grating (VBG) element that receives input light generated by a light-emitting device, conditions one or more characteristics of the input light, and causes the light-emitting device to generate light having the one or more characteristics of the conditioned light. 1. Apparatus for compressing laser pulses , the apparatus comprising:an optical amplifier; anda volume Bragg grating element comprising a three-dimensional bulk of optical material having a Bragg grating formed therein, the Bragg grating defining a Bragg grating vector and having a grating period that varies as a function of position along the Bragg grating vector,wherein the Bragg grating element is configured to compress chirped laser pulses received from the optical amplifier.2. The apparatus of claim 1 , wherein the Bragg grating element is configured to receive the chirped laser pulses from the optical amplifier.3. The apparatus of claim 1 , wherein the Bragg grating defines an entrance aperture of the Bragg grating element and an exit aperture of the Bragg grating element claim 1 , and wherein the entrance aperture and exit aperture coincide.4. The apparatus of claim 3 , wherein the entrance aperture defines a plane claim 3 , and the Bragg grating vector is normal to the plane defined by the entrance aperture.5. The apparatus of claim 3 , wherein the Bragg grating element is configured such that an incident chirped laser pulse that is incident on the entrance aperture is compressed and reflected through the exit aperture as a compressed laser pulse.6. The apparatus of claim 5 , wherein the incident chirped laser pulse has first pulse width before incidence on the entrance aperture claim 5 , and the compressed laser pulse has a second pulse width after reflection through the exit aperture claim 5 , and wherein the ...

Wavelength Stabilized Diode Laser

A hybrid external cavity laser and a method for configuring the laser having a stabilized wavelength is disclosed. The laser comprises a semiconductor gain section and a volume Bragg grating, wherein a laser emission from the semiconductor gain section is based on a combination of a reflectivity of a front facet of the semiconductor gain section and a reflectivity of the volume Bragg grating and the reflectivity of the semiconductor gain section and the volume Brag grating are insufficient by themselves to support the laser emission. The hybrid cavity laser further comprises an etalon that provides further wavelength stability. 1. A device configured to generate at least one laser emission , the device comprising:a semiconductor gain section generating a light emission, said semiconductor gain section comprising:a rear facet having a first reflectivity; anda front facet having a second reflectivity, said rear facet and said front facet forming a first resonant cavity having a first plurality of non-lasing resonance, and receive said light emission; and', 'reflect a portion of the received light emission back into the semiconductor gain section, wherein the rear facet of the semiconductor gain section and the volume Bragg grating form a second resonant cavity, overlapping the first resonant cavity, said second resonant cavity generating a second plurality of non-lasing resonances, wherein at least one of said first plurality of non-lasing resonances and a corresponding at least one of said second plurality of non-lasing is substantially coincident, said substantially at least one coincident resonance having a modal gain sufficient to generate corresponding ones of said at least one laser emission., 'a volume Bragg grating, having a known reflectivity, configured to2. The device of claim 1 , wherein the rear facet reflectivity is fixed and the front facet reflectivity is chosen such that the modal gain of the first plurality of resonances is less than said lasing ...

WAVELENGTH-TUNABLE TYPE ETALON COMPRISING LCD-LAYER AND PREPARATION METHOD THEREOF

The present invention relates to a wavelength-tunable type etalon comprising a liquid crystal layer, which comprises: a first substrate; a second substrate; a reflective coating film; a transparent electrode; an alignment layer, which is independently formed while covering the opposing surface of the transparent electrode; a liquid crystal layer, which is disposed in a space between each of the alignment layer s; and a sealing member, which is provided for sealing of the liquid crystal layer; and a method for manufacturing the same. 1. A wavelength-tunable type etalon comprising a liquid crystal layer , comprising:a first substrate;a second substrate;a pair of reflective coating films, which is provided at inner surface side of the first and second substrate, respectively;a pair of transparent electrodes, which is provided at intermediate of the first and second substrate;a pair of alignment layers, which is provided at intermediate of the first and second substrate;a liquid crystal layer, which is disposed in a cavity between each of the alignment layers; anda sealing member, which is provided for sealing of the liquid crystal layer.2. The wavelength-tunable type etalon of claim 1 , wherein the first and second substrates comprise at least one selected from glass claim 1 , quartz claim 1 , and silicon wafer so as to be substantially transparent in the band of 1300 nm to 1700 nm.3. The wavelength-tunable type etalon of claim 2 , wherein the alignment layer comprises an inorganic insulating film.4. The wavelength-tunable type etalon of claim 3 , wherein the inorganic insulating film comprises SiOor SiN.5. The wavelength-tunable type etalon of claim 3 , wherein the inorganic insulating film has a thickness in the range of 30 nm to 200 nm claim 3 , respectively.6. The wavelength-tunable type etalon of claim 3 , wherein the sealing member is provided along the periphery of the liquid crystal layer between the first and second substrates claim 3 , and is provided in ...

WAVELENGTH DETERMINATION FOR WIDELY TUNABLE LASERS AND LASER SYSTEMS THEREOF

Methods for wavelength determination of widely tunable lasers and systems thereof may be implemented with solid-state laser based photonic systems based on photonic integrated circuit technology as well as discrete table top systems such as widely-tunable external cavity lasers and systems. The methods allow integrated wavelength control enabling immediate system wavelength calibration without the need for external wavelength monitoring instruments. Wavelength determination is achieved using a monolithic solid-state based optical cavity with a well-defined transmission or reflection function acting as a wavelength etalon. The solid-state etalon may be used with a wavelength shift tracking component, e.g., a non-balanced interferometer, to calibrate the entire laser emission tuning curve within one wavelength sweep. The method is particularly useful for integrated photonic systems based on Vernier-filter mechanism where the starting wavelength is not known a-priori, or for compact widely tunable external cavity lasers eliminating the need for calibration of wavelength via external instruments. 1. A solid-state laser-based device comprising:a solid-state gain medium based widely tunable laser for emitting light;a wavelength shift tracking device for tracking a wavelength shift of the emitted light; anda solid-state based etalon comprising an optical element having at least one of an unambiguous transmission spectrum or an unambiguous reflection spectrum,wherein, during a wavelength sweep of the widely tunable laser, the solid-state based etalon and wavelength shift tracking device are configured to cooperate to provide absolute wavelength determination and control of the widely tunable laser.2. The solid-state laser-based device of claim 1 , wherein during the wavelength sweep claim 1 , the wavelength shift tracking device provides an output of wavelength shift as a function of time claim 1 , and the solid state etalon provides an output of a signal with information ...

EXTERAL CAVITY LASER INCORPORATING A RESETABLE PHASE SHIFTER

An apparatus including an external cavity laser with an optical cavity, the optical cavity bounded by optical reflectors. The optical cavity can include an optical gain module capable of amplifying light, a tunable endless optical phase shifter and a wavelength-tunable optical filter. The apparatus can also include an electronic control module connected to enable adjustment of a phase shift accumulated by the light propagating through the tunable endless optical phase shifter and connected to enable adjustment of a passband wavelength of the wavelength tunable optical filter. Another apparatus as described above with no wavelength-tunable optical filter present. 1. An apparatus comprising: an optical gain module capable of amplifying light,', 'a tunable endless optical phase shifter, and', 'a wavelength-tunable optical filter; and, 'an external cavity laser with an optical cavity, the optical cavity bounded by optical reflectors, wherein the optical cavity includesan electronic control module connected to enable adjustment of a phase shift accumulated by the light propagating through the tunable endless optical phase shifter and connected to enable adjustment of a passband wavelength of the wavelength tunable optical filter.2. The apparatus of claim 1 , wherein the electronic control module is capable of adjusting the accumulated phase shift and the passband wavelength in parallel.3. The apparatus of claim 1 , wherein the electronic control module is able to cause a phase shift accumulated by the light propagating through the tunable endless optical phase shifter to vary with an amount of a multiple of 2π radians without causing a substantial change in lasing optical power.4. The apparatus of claim 1 , wherein the tunable endless optical phase shifter includes:a first optical switch;a second optical switch; andfirst and second optical waveguide paths, each optical waveguide path optically connecting a corresponding optical output of the first optical switch to a ...

Stabilized diode laser

A process for creating a stabilized diode laser device is disclosed, where the stabilized diode laser device includes a unibody mounting plate and several chambers aligned along a transmission axis. Various optic components are placed in the chambers, and based on a transmission through the chambers, the optic components are aligned and secured within the chambers.

RAPIDLY TUNABLE LASER ASSEMBLY

A laser assembly for generating an output beam includes a first module assembly, a second module assembly, and a module fastener assembly. The second module assembly is selectively movable relative to the first module assembly to selectively adjust a cavity length, and a pivot axis of a grating in the laser. Further, an arm assembly that retains the grating can be adjusted to adjust the cavity length, and to adjust the plane of the grating face. Moreover, the grating is movable relative to the arm assembly to align the grating. 117-. (canceled)18. A laser assembly for emitting an output beam , the laser assembly comprising:a first module assembly that includes (i) a rigid first frame; and (ii) a gain medium coupled to the first frame, the gain medium having a facet, the gain medium generating a beam that exits the facet along a lasing axis when sufficient current is directed to the gain medium;a second module assembly that includes (i) a rigid second frame; (ii) a diffraction grating positioned in the path of the beam exiting the facet to form an external cavity having a cavity length; (iii) an arm assembly that retains the diffraction grating; and (iv) a pivot assembly that secures the arm assembly to the second frame in a fashion that allows the arm assembly and the grating to effectively pivot about a pivot axis; anda module fastener assembly that is moveable between (i) an unlocked position in which the second frame can be selectively moved relative to the first frame to selectively adjust at least one of the cavity length, and the position of the pivot axis relative to the lasing axis; and (ii) a locked position in which the second module assembly is fixedly secured to the first module assembly to inhibit relative movement between the first frame and the second frame.19. The laser assembly of wherein in the unlocked position claim 18 , the second frame can be selectively moved relative to the first frame to selectively adjust the cavity length.20. The laser ...

Broadband Tunable External-Cavity Laser Using Small Mems Mirror

A Raman pump laser control apparatus comprises a wavelength division multiplexer, a tap coupler, a photoelectric detector, an analogue amplification processing circuit, an analogue-to-digital converter, a fast Raman pump control unit, an digital-analog converter, and a Raman pump laser. The fast Raman pump control unit, after having known anticipated output light power of the Raman pump laser, based on a direct relationship between a current anticipated output light power of the Raman pump laser and input digital quantity that is needed by the digital-analog converter, uses a feedforward control mechanism so that actual output light power of the Raman pump laser fastly approximates the anticipated output light power thereof, and then synchronously combines with a feedback control mechanism so that the actual output light power of the Raman pump laser is precisely locked on the anticipated output light power, thereby achieving fast and precise control of the Raman pump laser.

EXTERNAL CAVITY LASER BASED WAVELENGTH DIVISION MULTIPLEXING SUPERCHANNEL TRANSCEIVERS

A technique relates to a superchannel. Laser cavities include a first laser cavity, a next laser cavity, through a last laser cavity. Modulators include a first modulator, a next modulator, through a last modulator, each having a direct input, an add port, and an output. A concatenated arrangement of the laser cavities is configured to form the superchannel, which includes the last laser cavity coupled to the direct input of the last modulator, and the output of the last modulator coupled to the add port of the next modulator. The arrangement includes the next laser cavity coupled to direct input of the next modulator, and the output of the next modulator coupled to add port of first modulator, along with the first laser cavity coupled to direct input of the first modulator, and the output of first modulator coupled to input of a multiplexer, thus forming the superchannel into multiplexer. 1. A semiconductor chip configured as a receiver to receive a superchannel , the semiconductor chip comprising:a polarization splitter rotator configured to receive and split received light of the superchannel;wavelength division multiplexing (WDM) demultiplexers configured to demultiplex the received light; andcounter propagating drop filters configured to capture the received light at a particular target wavelength and generate an electrical signal;wherein each of the counter propagating drop filters is coupled to an electrical receiver, the electrical receiver receives the electrical signal corresponding to the particular target wavelength.2. The semiconductor chip of claim 1 , wherein the counter propagating drop filters comprise a ring resonator configured to capture the received light at the particular target wavelength from a waveguide.3. The semiconductor chip of claim 2 , wherein the counter propagating drop filters each comprise a photodiode that converts the received light at the particular wavelength into the electrical signal that is sent to the electrical receiver.4. ...

LASER DEVICE

The invention relates to a laser device, comprising a laser configured to generate laser light and a laser control module configured to receive at least a portion of the laser light generated by the laser, to generate a control signal and to feed the control signal back to the laser for stabilizing the frequency, wherein the laser control module comprises a tunable frequency discriminating element which is preferably continuously frequency tunable, and where the laser control module is placed outside the laser cavity. 139.-. (canceled)40. A sensor comprising a laser device , comprising:a tunable laser configured to generate laser light and a laser control module configured to receive at least a portion of the laser light generated by the laser to generate a control signal and to feed the control signal back to the laser for stabilizing the frequency,wherein the laser comprises a laser cavity and the laser control module comprises a tunable frequency discriminating element which is preferably continuously frequency tunable, and where the laser control module is placed outside the laser cavity,wherein the laser control module is encapsulated inside a hermetically sealed housing.41. The sensor according claim 40 , wherein the tunable laser operates in a single longitudinal mode42. The sensor according to claim 40 , wherein the tunable laser is a fiber laser claim 40 , a diode laser or a solid-state laser43. The sensor according to claim 40 , wherein the frequency discriminating element comprises solid silica44. The sensor according to claim 40 , wherein the laser control module is fiber coupled to the tunable laser.45. The sensor according to claim 40 , wherein the laser control module is temperature controlled46. The sensor according to claim 40 , wherein the frequency discriminating element is an interferometer.47. The sensor according to claim 46 , wherein the interferometer is a Fabry-Perot interferometer.48. The sensor according to claim 46 , wherein the ...

EFFICIENT GENERATION OF SPATIALLY-RESTRUCTURABLE HIGH-ORDER HG-MODES IN A LASER CAVITY

A vertical external cavity surface emitting laser (VECSEL) based system in a linear single cavity configuration is configured to deliver light in higher-order Hermite-Gaussian transverse modes with Watt-level output power. Simultaneous and independent lasing of spatially-restructurable multiple high-order transverse modes that are collinearly-propagating at the output of such laser cavity is facilitated with the use of an optical pumping scheme devised to control positions of location at which the gain medium of the system is pumped (e.g., locations of focal spots of multiple pump beams on the gain-medium chip). An external astigmatic mode converter is utilized to convert such high-order Hermite-Gaussian modes into corresponding Laguerre-Gaussian modes. 1. A laser system , comprising:a linear laser cavity having a laser cavity axis and defined by first and second reflectors;a laser gain medium chip containing said first reflector;the second reflector dimensioned to have a center of curvature of the second reflector at an axial point of the first reflector;multiple pump channels configured to deliver pumping energy to the laser gain medium chip at respectively-corresponding multiple initial locations of a surface of the laser gain medium chip in a fashion that allows for spatially-varying said multiple initial locations; anda mechanism configured to cause, during the operation of the laser system, a change of first and second of said multiple initial locations to respectively-corresponding third and fourth locations.2. The laser system according to claim 1 , further comprising an astigmatic mode converter (AMC) system outside of the laser cavity on the laser cavity axis.3. The laser system according to claim 2 , wherein the AMC system is configured to have at least one of optical elements of the AMC system to be rotated about the laser cavity axis.4. (canceled)5. The laser system according to claim 1 , wherein at least one of the following conditions is satisfied:a) ...

Optical device and manufacturing method thereof

Provided is an optical device including a first optical waveguide on one side of a substrate; a laser separated from the first optical waveguide and disposed on the other side of the substrate; and a first coupled waveguide between the laser and the first optical waveguide. The laser may be monolithically integrated on the substrate.

GALLIUM NITRIDE CROSS-GAP LIGHT EMITTERS BASED ON UNIPOLAR-DOPED TUNNELING STRUCTURES

Gallium nitride based devices and, more particularly to the generation of holes in gallium nitride based devices lacking p-type doping, and their use in light emitting diodes and lasers, both edge emitting and vertical emitting. By tailoring the intrinsic design, a wide range of wavelengths can be emitted from near-infrared to mid ultraviolet, depending upon the design of the adjacent cross-gap recombination zone. The innovation also provides for novel circuits and unique applications, particularly for water sterilization. 1. A solid-state device , comprising:a bottom n-type layer;a top n-type layer;a middle layer inserted between the top layer and bottom layer, where the middle layer comprises at least two materials provided between the top and bottom layers which serve as heterojunction tunnel barriers;and where the top layer and the middle layer form an interband tunnel barrier to generate holes by Zener tunneling across the potential barrier of the forbidden energy gap, and where the middle layer forms at least one intraband tunnel barrier to control electron flow.2. The device of claim 1 , wherein the top claim 1 , middle and bottom layers are comprised of gallium nitride claim 1 , aluminum nitride claim 1 , indium nitride or alloys and combinations of III-nitride semiconductors or III-nitride compatible semiconductors.3. The device of claim 2 , wherein the heterojunction interband tunnel barrier is formed by the polarization effects at III-nitride heterojunctions.4. The device of claim 1 , wherein the middle layer forms at least two intraband tunnel barriers claim 1 , wherein the at least two intraband tunnel barriers form a quantum well within the middle layer.5. The device of claim 1 , wherein the middle layer forms at least two intraband tunnel barriers claim 1 , wherein the at least two intraband tunnel barriers form a double barrier resonant tunneling diode.6. The device of claim 1 , wherein the middle layer is either undoped or doped less than the top ...

Quantum Cascade Laser with Serially Configured Gain Sections

An apparatus that includes a gain chip assembly, an external cavity, and a controller is disclosed. The gain chip assembly includes first and second gain chips that are coupled optically such that light travels serially between the first gain chip and the second gain chip, each gain chip is electrically biased. The electrical bias of the first gain chip is independent of the electrical bias of the second gain chip. The external cavity has a tunable wavelength selective filter that is changed in response to a control signal. Light in the external cavity passes through the gain chip assembly. The controller determines the tunable wavelength selective filter, and the electrical bias of each of the gain chips so as to cause the apparatus to lase at a wavelength specified by a control signal to the controller. 1. An apparatus comprising:a gain chip assembly comprising first and second gain chips that are coupled optically such that light travels serially between said first gain chip and said second gain chip, each gain chip being electrically biased, said electrical bias of said first gain chip being independent of said electrical bias of said second gain chip;an external cavity having a tunable wavelength selective filter that selectively passes light in a pass band that is changed in response to a control signal, light in said external cavity passing through said gain chip assembly; anda controller that generates said control signal, and said electrical bias of each of said gain chips,wherein said first gain chip comprises an active layer comprising a first sub-layer having a plurality of quantum well layers characterized by a first quantum well thickness, said second gain chip comprises an active layer having second and third sub-layers, said second sub-laver comprising a plurality of quantum well layers characterized by a second quantum well thickness, and said third sub-layer comprising a plurality of quantum well layers Characterized by a third quantum well ...

SEMICONDUCTOR LASER DEVICE

A semiconductor laser device includes: a semiconductor laser array in which a plurality of active layers that emit laser lights with a divergence angle θ(>4°) in a slow axis direction are arranged; a first optical element that reflects first partial lights by a first reflecting surface and returns the first partial lights to the active layers; and a second optical element that reflects partial mode lights of second partial lights by a second reflecting surface and returns the partial mode lights to the active layers, the first reflecting surface forms an angle equal to or greater than 2° and less than (θ/2) with a plane perpendicular to an optical axis direction of the active layers, and the second reflecting surface forms an angle greater than (−θ/2) and equal to or less than −2° with the plane perpendicular to the optical axis direction of the active layers. 1. A semiconductor laser device comprising:{'sub': 'S', 'a semiconductor laser array in which a plurality of active layers that emit laser lights with a divergence angle θ(>4°) in a slow axis direction are arranged in the slow axis direction;'}a collimating lens that collimates the laser lights emitted from each of the active layers in a plane perpendicular to the slow axis direction;a first optical element that reflects first partial lights advancing to one side in the slow axis direction from among each of the laser lights emitted from the collimating lens by a first reflecting surface and returns the first partial lights to each of the active layers via the collimating lens; anda second optical element that reflects a part of the mode lights of a plurality of mode lights of second partial lights advancing to the other side in the slow axis direction from among each of the laser lights emitted from the collimating lens by a second reflecting surface and returns the part of the mode lights to each of the active layers via the collimating lens,{'sub': 'S', 'wherein the first optical element is disposed such ...

SINGLE LONGITUDINAL MODE LASER DIODE SYSTEM

A semiconductor laser diode system may include a single longitudinal mode laser diode and a feedback system that monitors and controls the emission characteristics of the laser diode. The laser diode may include a gain medium and an optical feedback device. The feedback system may include a wavelength discriminator, an optical detector, a microprocessor, and a laser controller. Such a semiconductor laser diode system may be used to produce laser light having coherence length, wavelength precision, and wavelength stability that is equivalent to that of a gas laser. Accordingly, such a semiconductor laser diode system may be used in place of a traditional gas laser. 1. A semiconductor laser diode system , comprising:a semiconductor laser source having a laser cavity;an optical feedback device, wherein the optical feedback device is a three-dimensional optical element having a Bragg grating recorded therein, and wherein the Bragg grating causes a narrowband portion of radiation emitted from the laser source to be fed back into the laser cavity, the optical feedback device being configured to cause the laser diode to achieve single longitudinal mode at a desired wavelength; anda feedback system that monitors emission characteristics of the laser diode, the feedback system comprising a processor that is configured to adjust one or more control characteristics of the laser diode to cause the laser diode to achieve and maintain a single longitudinal mode condition using only output power characteristics of the laser diode.2. The semiconductor laser diode system of claim 1 , wherein the Bragg grating causes the narrowband portion of the radiation emitted from the laser source to be fed back into the laser cavity as seed light at the desired wavelength.3. The semiconductor laser diode system of claim 1 , wherein the Bragg grating causes the narrowband portion of the radiation emitted from the laser source to be reflected back into the laser cavity as seed light at the ...

Laser component and laser generating apparatus

A laser component includes multiple laser devices arranged in an array to include different emission wavelengths, and a driving unit that, while switching each of the laser devices along the array into a turn-ON-enabled state that enables the laser device to turn to an ON state, brings one of the laser devices that has an emission wavelength corresponding to a predetermined wavelength into an ON state and maintains the ON state.

Dual output laser diode

A dual output laser diode may include first and second end facets and an active section. The first and second end facets have low reflectivity. The active section is positioned between the first end facet and the second end facet. The active section is configured to generate light that propagates toward each of the first and second end facets. The first end facet is configured to transmit a majority of the light that reaches the first end facet through the first end facet. The second end facet is configured to transmit a majority of the light that reaches the second end facet through the second end facet.

NARROW LINEWIDTH EXTERNAL CAVITY LASER AND OPTICAL MODULE

A narrow linewidth external cavity laser includes a sealed housing, an external resonant cavity disposed in the sealed housing, and a gain chip and a tunable wavelength selective component disposed in the external resonant cavity. An electrical interface of the sealed housing is configured to receive an electrical signal such as a drive signal, a wave selection signal, a cavity length control signal, and a dither control signal. The cavity length control signal is configured to adjust an optical cavity length of the external resonant cavity so that a laser mode produced in the external resonant cavity aligns with a wavelength selected by the wavelength selective component. The dither control signal is configured to control the optical cavity length of the external resonant cavity to produce dither by adjusting an optical length of the gain chip in order to lock a center wavelength of an output light beam. 1. A narrow linewidth external cavity laser comprising:a sealed housing having disposed thereon an optical interface and an electrical interface;an external resonant cavity disposed in the sealed housing; anda gain chip and a tunable wavelength selective component that are disposed in the external resonant cavity,whereinthe electrical interface is configured to receive an electrical signal comprising a drive signal, a wave selection signal, a cavity length control signal, and a dither control signal,the drive signal is configured to drive the gain chip to emit a light beam, the light beam resonating in the external resonant cavity to produce a laser mode;the wave selection signal is configured to tune the wavelength selective component to select a wavelength;the cavity length control signal is configured to adjust an optical cavity length of the external resonant cavity so that the laser mode aligns with the wavelength selected by the wavelength selective component;the dither control signal is configured to control the optical cavity length of the external resonant ...

Tunable laser source, optical transmitter, and optical transmitter and receiver module

A tunable laser source includes a mirror, a tunable filter, and a semiconductor optical amplifier integrated device including first, second, and third semiconductor optical amplifiers between a first end face facing toward the tunable filter and a second end face facing away from the first end face. The first amplifier is closer to the first end face than the second and third amplifiers. The semiconductor optical amplifier integrated device further includes a partially reflecting mirror and an optical divider that are disposed between the first amplifier and the second and third amplifiers. The partially reflecting mirror is closer to the first amplifier than the optical divider. The optical divider includes first and second branches connected to the second and third semiconductor optical amplifiers, respectively. The tunable filter and the first amplifier are disposed in an optical path between the partially reflecting mirror and the mirror that form a laser resonator.

Distributed reflector laser

A distributed reflector (DR) laser may include a distributed feedback (DFB) region and a distributed Bragg reflector (DBR). The DFB region may have a length in a range from 30 micrometers (μm) to 100 μm and may include a DFB grating with a first kappa in a range from 100 cm−1 to 150 cm−1. The DBR region may be coupled end to end with the DFB region and may have a length in a range from 30-300 μm. The DBR region may include a DBR grating with a second kappa in a range from 150 cm−1 to 200 cm−1. The DR laser may additionally include a lasing mode and a p-p resonance frequency. The lasing mode may be at a long wavelength side of a peak of a DBR reflection profile of the DBR region. The p-p resonance frequency may be less than or equal to 70 GHz.

EXTERNAL CAVITY LASER

Embodiments of systems and methods are provided for a tunable laser device. The tunable laser device may include a diffraction grating connected to a pivot arm that pivots the diffraction grating about a pivot point to tune the laser device. In pivoting the diffraction grating about the pivot point, both the wavelength to which the diffraction grating is tuned and the length of the optical cavity may be changed. The length of the pivot arm may be selected to reduce the number of mode hops of the tunable laser device when tuning the laser device over its tuning range. 1. A laser system comprising:a laser cavity including a first end and a second end;a light source (i) residing within the laser cavity, (ii) providing a coherent light beam, and (iii) including a reflective surface disposed at the first end of the laser cavity;a lens disposed between the light source and the second end of the laser cavity, the lens being configured to collimate the coherent light beam to provide a collimated coherent light beam;a diffraction grating disposed at the second end of the laser cavity, the diffraction grating having an angular position relative to the collimated light beam that results in the diffraction grating reflecting a selected wavelength of the collimated coherent light beam through the lens toward the reflective surface; anda pivot arm connected to the diffraction grating, the pivot arm and the diffraction grating being configured to change the angular position of the diffraction grating relative to the collimated coherent light beam upon rotation of the pivot arm about a rotational axis; the reflective surface reflects the selected wavelength of the collimated coherent light beam through the lens toward the diffraction grating;', {'sup': 'th', 'a 0order grating transmission of the collimated coherent light beam is transmitted by the diffraction grating to provide a collimated output beam disposed at an output angle relative to the collimated coherent light beam; and ...

GRATING ELEMENT AND EXTERNAL RESONATOR TYPE LIGHT EMITTING DEVICE

A grating element includes: a support substrate; an optical material layer; a ridge optical waveguide having an incidence surface on which a laser light is incident and an emission end from which an emission light with a desired wavelength is emitted; and a Bragg grating including concave and convex portions formed within the optical waveguide. The optical waveguide includes an incident portion between the incidence surface and the Bragg grating, and a tapered portion between the incident portion and the Bragg grating. In the Bragg grating, a propagation light propagates in single mode. The width Wof the optical waveguide in the incident portion is larger than the width Wof the optical waveguide in the Bragg grating. The width Wof the optical waveguide in the tapered portion is decreased from the incident portion toward the Bragg grating. The relationships represented by formulas (1) to (3) are satisfied. 1. A grating element comprising:a support substrate;an optical material layer disposed over said support substrate;a ridge optical waveguide disposed in said optical material layer, said ridge optical waveguide having an incidence surface to which a laser light is incident and an emission end from which an emission light with a desired wavelength is emitted; anda Bragg grating comprising concave and convex portions formed within said ridge optical waveguide,wherein said ridge optical waveguide comprises an incident portion disposed between said incidence surface and said Bragg grating, and a tapered portion disposed between said incident portion and said Bragg grating,wherein a propagating light propagates at least in said Bragg grating in a single mode,wherein a width of said ridge optical waveguide in said incident portion is larger than a width of said ridge optical waveguide in said Bragg grating,wherein a width of said ridge optical waveguide in said tapered portion is decreased from said incident portion toward said Bragg grating, and [{'br': None, 'sub': 'G ...

Optical Coherence Tomography Laser with Integrated Clock

A frequency swept laser source for TEFD-OCT imaging includes an integrated clock subsystem on the optical bench with the laser source. The clock subsystem generates frequency clock signals as the optical signal is tuned over the scan band. Preferably the laser source further includes a cavity extender in its optical cavity between a tunable filter and gain medium to increase an optical distance between the tunable filter and the gain medium in order to control the location of laser intensity pattern noise. The laser also includes a fiber stub that allows for control over the cavity length while also controlling birefringence in the cavity. 1. A sampling clock system for an optical coherence analysis system including a swept source generating a tunable optical signal , an interferometer that receives the tunable optical signal from the swept source via an optical fiber and conveys the optical signal on a reference arm and a sample arm and combines the optical signal returning from the reference arm and the sample arm to generate a combined signal , a detector system that detects the combined signal , and a sampling system that samples an output of the detector system and receives an electronic clock , the sampling clock system comprising:an optical detector for detecting an optical clock signal generated by optically filtering the tunable optical signal from the swept source to generate the electronic clock; andan electronic time delay circuit for delaying the electronic clock by an amount corresponding to the propagation time of the light from the swept source in the optical coherence analysis system that includes the optical fiber, the interferometer arms and path to the detector system to improve delay matching between the electronic clock and the combined signal.2. A system as claimed in claim 1 , wherein the electronic time delay circuit imparts a programmable delay to the electronic clock.3. A system as claimed in claim 1 , further comprising a high pass filter ...

METHODS AND SYSTEM FOR WAVELENGTH TUNABLE OPTICAL COMPONENTS AND SUB-SYSTEMS

Wavelength division multiplexing (WDM) has enabled telecommunication service providers to provide multiple independent multi-gigabit channels on one optical fiber.-To meet demands for improved performance, increased integration, reduced footprint, reduced power consumption, increased flexibility, re-configurability, and lower cost monolithic optical circuit technologies and microelectromechanical systems (MEMS) have become increasingly important. However, further integration via microoptoelectromechanical systems (MOEMS) of monolithically integrated optical waveguides upon a MEMS provide further integration opportunities and functionality options. Such MOEMS may include MOEMS mirrors and optical waveguides capable of deflection under electronic control. In contrast to MEMS devices where the MEMS is simply used to switch between two positions the state of MOEMS becomes important in all transition positions. Improvements to the design and implementation of such MOEMS mirrors, deformable MOEMS waveguides, and optical waveguide technologies supporting MOEMS devices are presented where monolithically integrated optical waveguides are directly supported, moved and/or deformed by a MEMS. 1. A device comprising:an optical waveguide structure comprising a first predetermined portion formed from a plurality of three-dimensional (3D) optical waveguides for routing an optical signal upon a substrate and a second predetermined portion comprising an input 3D optical waveguide for routing the optical signals from a first subset of the plurality of 3D optical waveguides to or from the input 3D optical waveguide; anda rotational microoptoelectromechanical (MOEMS) element comprising a pivot and an actuator supporting the input 3D optical waveguide; whereina predetermined rotation of the MOEMS element under the motion of the actuator results in an alignment of the input 3D optical waveguide with a predetermined 3D optical waveguide of the first subset of the plurality of 3D optical ...

METHODS AND SYSTEM FOR WAVELENGTH TUNABLE OPTICAL COMPONENTS AND SUB-SYSTEMS

Wavelength division multiplexing (WDM) has enabled telecommunication service providers to provide multiple independent multi-gigabit channels on one optical fiber.-To meet demands for improved performance, increased integration, reduced footprint, reduced power consumption, increased flexibility, re-configurability, and lower cost monolithic optical circuit technologies and microelectromechanical systems (MEMS) have become increasingly important. However, further integration via microoptoelectromechanical systems (MOEMS) of monolithically integrated optical waveguides upon a MEMS provide further integration opportunities and functionality options. Such MOEMS may include MOEMS mirrors and optical waveguides capable of deflection under electronic control. In contrast to MEMS devices where the MEMS is simply used to switch between two positions the state of MOEMS becomes important in all transition positions. Improvements to the design and implementation of such MOEMS mirrors, deformable MOEMS waveguides, and optical waveguide technologies supporting MOEMS devices are presented where monolithically integrated optical waveguides are directly supported, moved and/or deformed by a MEMS. 1. An optical device comprising:a substrate; a rotatable microelectromechanical systems (MEMS) element; and', 'a first optical waveguide formed upon the rotatable MEMS element rotating under action of the rotatable MEMS element; and', 'a grating formed upon the rotatable MEMS element optically coupled to a facet of the first optical waveguide;, 'a rotational microoptoelectromechanical systems (MOEMS) element integrated upon the substrate in a first predetermined position comprisinga second optical waveguide integrated upon the substrate having a first end disposed at a first predetermined position with respect to the rotational MOEMS element; whereinrotation of the grating under action of the rotatable MEMS element reflects a predetermined portion of optical signals coupled to it from the ...

METHODS AND SYSTEM FOR WAVELENGTH TUNABLE OPTICAL COMPONENTS AND SUB-SYSTEMS

Wavelength division multiplexing (WDM) has enabled telecommunication service providers to provide multiple independent multi-gigabit channels on one optical fiber. To meet demands for improved performance, increased integration, reduced footprint, reduced power consumption, increased flexibility, re-configurability, and lower cost monolithic optical circuit technologies and microelectromechanical systems (MEMS) have become increasingly important. However, further integration via microoptoelectromechanical systems (MOEMS) of monolithically integrated optical waveguides upon a MEMS provide further integration opportunities and functionality options. Such MOEMS may include MOEMS mirrors and optical waveguides capable of deflection under electronic control. In contrast to MEMS devices where the MEMS is simply used to switch between two positions the state of MOEMS becomes important in all transition positions. Improvements to the design and implementation of such MOEMS mirrors, deformable MOEMS waveguides, and optical waveguide technologies supporting MOEMS devices are presented where monolithically integrated optical waveguides are directly supported, moved and/or deformed by a MEMS. 1. An optical source comprising:a substrate;an optical cavity comprising a first high reflectivity facet, a second high reflectivity facet, and a semiconductor optical amplifier (SOA) disposed between the first high reflectivity facet and the second high reflectivity facet; whereinthe first high reflectivity facet comprises at least a tunable optical wavelength filter employing a rotational microoptoelectromechanical (MOEMS) element integrated upon the substrate;the first high reflectivity facet has a high reflectivity over a predetermined bandwidth determined by the tunable optical wavelength filter; anda center wavelength of the optical source can be set to one of a plurality of predetermined wavelengths within a predetermined wavelength range based upon setting the tunable optical ...

EXTERNAL RESONANCE TYPE LASER MODULE, ANALYSIS APPARATUS, METHOD OF DRIVING EXTERNAL RESONANCE TYPE LASER MODULE, AND NON-TRANSITORY COMPUTER READABLE MEDIUM

An external resonance type laser module includes a quantum cascade laser, a MEMS diffraction grating configured to include a diffraction/reflection portion configured to diffract and reflect light emitted from the quantum cascade laser and return a part of the light to the quantum cascade laser by swinging the diffraction/reflection portion, and a controller configured to control driving of the quantum cascade laser. The controller is configured to pulse-drive the quantum cascade laser such that pulsed light of a second frequency higher than a first frequency at which the diffraction/reflection portion swings is emitted from the quantum cascade laser and a phase of the pulsed light changes each time the diffraction/reflection portion reciprocates m times (m: an integer of 1 or more). 1. An external resonance type laser module comprising:a quantum cascade laser;a MEMS diffraction grating configured to include a diffraction/reflection portion that diffracts and reflects light emitted from the quantum cascade laser and to return a part of the light to the quantum cascade laser by swinging the diffraction/reflection portion; anda controller configured to control driving of the quantum cascade laser,wherein the controller is configured to pulse-drive the quantum cascade laser such that pulsed light of a second frequency higher than a first frequency at which the diffraction/reflection portion swings is emitted from the quantum cascade laser and a phase of the pulsed light changes each time the diffraction/reflection portion reciprocates m times (m: an integer of 1 or more).2. The external resonance type laser module according to claim 1 , wherein the controller is configured to pulse-drive the quantum cascade laser such that the phase of the pulsed light changes by a predetermined value each time the diffraction/reflection portion reciprocates m times.3. The external resonance type laser module according to claim 2 , wherein the predetermined value is equal to a pulse ...

Self mode-locking semiconductor disk laser

The present invention describes a self mode locking laser and a method for self mode locking a laser. The laser ( 1 ) comprises a resonator terminated by first ( 3 ) and second ( 4 ) mirrors and folded by a third mirror ( 5 ). The third mirror comprises a single distributed Bragg reflector ( 17 ) upon which is mounted a multilayer semiconductor gain medium ( 18 ) and which includes at least one quantum well layer and an optical Kerr lensing layer ( 22 ). Self mode locking may be achieved by configuring the laser resonator such that the lensing effect of the Kerr lensing layer acts to reduce an astigmatism deliberately introduced to the cavity mode. The self mode locking of the laser may be further enhanced by selecting the length of the resonator such that a round trip time of a cavity mode is matched with an upper-state lifetime of one or more semiconductor carriers located within the gain medium.

Radiation output device and method thereof

The present application provides a radiation output device and a method. The radiation output device includes a radiation generating module configured to generate initial radiation; a filter module configured to reflect a portion of a first preset wavelength of the initial radiation to the radiation generating module and transmit a portion of a second preset wavelength of the initial radiation, the transmitted radiation is therefore used as an output radiation of the radiation output device; a detection feedback module, using a portion of or all of the output radiation as a feedback radiation, configured to instruct a modulating module to modulate the filter module according to the feedback radiation. The modulating module is connected to the filter module and configured to modulate a position and/or an angle of the filter module according to the instruction of the detection feedback module.

DIODE LASER PACKAGES WITH FLARED LASER OSCILLATOR WAVEGUIDES

A high brightness diode laser package includes a plurality of flared laser oscillator waveguides arranged on a stepped surface to emit respective laser beams in one or more emission directions, a plurality of optical components situated to receive the laser beams from the plurality of flared laser oscillator waveguides and to provide the beams in a closely packed relationship, and an optical fiber optically coupled to the closely packed beams for coupling the laser beams out of the diode laser package. 1. A high brightness diode laser package , comprising:a plurality of flared laser oscillator waveguides arranged on a stepped surface to emit respective laser beams in one or more emission directions;a plurality of optical components situated to receive the laser beams from said plurality of flared laser oscillator waveguides and to provide the beams in a closely packed relationship; andan optical fiber optically coupled to the closely packed beams for coupling the laser beams out of the diode laser package.2. The package of wherein said plurality of flared laser oscillator waveguides includes a first set of three or more of said flared laser oscillator waveguides arranged on a first stepped surface portion of said stepped surface at successive heights thereof such that a first set of beams is emitted parallel to each other and said first stepped surface portion in a first stepped configuration in a first emission direction;wherein said plurality of optical components includes a first set of optical components associated with said first set of three or more flared laser oscillator waveguides, said first set of optical components including fast-axis collimation optics and slow-axis collimation optics for collimating the respective fast and slow axes of the first set of beams and beam-turning optics coupled to each first set beam so as to provide each first set beam in a first set turn direction such that the first stepped configuration of beams becomes a first stacked ...

OPTICAL CROSS-COUPLING MITIGATION SYSTEMS FOR WAVELENGTH BEAM COMBINING LASER SYSTEMS

In various embodiments, wavelength beam combining laser systems incorporate optical cross-coupling mitigation systems and/or engineered partially reflective output couplers in order to reduce or substantially eliminate unwanted back-reflection of stray light. 130.-. (canceled)31. A laser system comprising:an array of beam emitters each emitting a beam having a different wavelength;focusing optics for focusing the beams toward a dispersive element;a dispersive element for receiving and dispersing the focused beams, thereby forming a multi-wavelength beam; andan output coupler comprising (i) a beam-receiving portion for receiving the multi-wavelength beam, reflecting a first portion thereof back to the array of beam emitters via the dispersive element, and transmitting a second portion thereof as an output beam composed of multiple wavelengths, and (ii) a non-reflective portion.32. The laser system of claim 31 , wherein the beam-receiving portion of the output coupler is at least as large as a diameter of the multi-wavelength beam.33. The laser system of claim 31 , wherein the beam-receiving portion of the output coupler protrudes above the non-reflective portion.34. The laser system of claim 31 , wherein the non-reflective portion at least partially surrounds the beam-receiving portion.35. The laser system of claim 31 , wherein a reflectivity to the multi-wavelength beam of the non-reflective portion is less than 1%.36. The laser system of claim 31 , wherein a reflectivity to the multi-wavelength beam of the beam-receiving portion is less than approximately 15%.37. The laser system of claim 31 , wherein a reflectivity to the multi-wavelength beam of the beam-receiving portion ranges from approximately 2% to approximately 10%.38. The laser system of claim 31 , further comprising a non-reflective coating disposed over the non-reflective portion of the output coupler.39. The laser system of claim 31 , further comprising an end cap over the beam-receiving portion of the ...

TWO-DIMENSIONAL MULTI-BEAM STABILIZER AND COMBINING SYSTEMS AND METHODS

A system and method for stabilizing and combining multiple emitted beams into a single system using both WBC and WDM techniques. 120.-. (canceled)21. A method of forming a multi-wavelength beam output , the method comprising:stabilizing beams emitted by a plurality of emitters each to a unique wavelength by introducing each beam to a stabilizing dispersive element that (i) reflects a portion of the beam back to its emitter to stabilize the beam and (ii) transmits the stabilized beam; andtransmitting the stabilized beams to a combining dispersive element, the combining dispersive element combining the stabilized beams into the multi-wavelength beam output.22. The method of claim 21 , wherein claim 21 , for each emitted beam claim 21 , the stabilizing dispersive element comprises a grating claim 21 , a chirped grating claim 21 , a surface grating claim 21 , a volume grating claim 21 , a transmission grating claim 21 , or a prism.23. The method of claim 21 , wherein claim 21 , for each emitted beam claim 21 , the stabilizing dispersive element comprises a diffraction grating.24. The method of claim 21 , wherein the combining dispersive element comprises a grating claim 21 , a chirped grating claim 21 , a surface grating claim 21 , a volume grating claim 21 , a transmission grating claim 21 , or a prism.25. The method of claim 21 , wherein the combining dispersive element comprises a diffraction grating.26. The method of claim 21 , wherein each of the beam emitters comprises a diode laser.27. The method of claim 21 , further comprising collimating each beam after emission thereof by its beam emitter.28. The method of claim 21 , wherein transmitting the stabilized beams to the combining dispersive element comprises converging the stabilized beams toward the combining dispersive element.29. The method of claim 21 , wherein the multi-wavelength beam output is transmitted away from the beam emitters.30. A system for forming a multi-wavelength beam output claim 21 , the ...

MOVABLE DIFFRACTION GRATING, METHOD OF MANUFACTURING THE SAME, AND EXTERNAL RESONATOR TYPE LASER MODULE

A movable diffraction grating includes: a support portion; a movable portion swingably connected to the support portion; a coil buried in the movable portion; a magnetic field generator configured to apply a magnetic field to the coil; an insulation layer provided on a surface of the movable portion; a resin layer provided on the insulation layer and provided with a diffraction grating pattern; and a reflection layer formed of a metal and provided on the resin layer to follow the diffraction grating pattern. 1. A movable diffraction grating comprising:a support portion;a movable portion swingably connected to the support portion;a coil buried in the movable portion;a magnetic field generator configured to apply a magnetic field to the coil;an insulation layer provided on a surface of the movable portion;a resin layer provided on the insulation layer and provided with a diffraction grating pattern; anda reflection layer formed of a metal and provided on the resin layer to follow the diffraction grating pattern.2. The movable diffraction grating according to claim 1 ,wherein the coil is disposed inside a groove formed in the surface of the movable portion.3. The movable diffraction grating according to claim 1 ,wherein the diffraction grating pattern is disposed in an area overlapping the coil when viewed in a direction perpendicular to the surface of the movable portion.4. The movable diffraction grating according to claim 1 ,wherein the diffraction grating pattern is a blazed grating pattern diffracting light having a wavelength in a mid-infrared region.5. A method of manufacturing the movable diffraction grating according to claim 1 , comprising:a first step of preparing a substrate including a portion corresponding to the support portion and the movable portion and forming the coil to be buried in the movable portion;a second step of forming the insulation layer on the surface of the movable portion after the first step;a third step of disposing a resin material ...

Quantum dot soa-silicon external cavity multi-wavelength laser

A hybrid external cavity multi-wavelength laser using a QD RSOA and a silicon photonics chip is demonstrated. Four lasing modes at 2 nm spacing and less than 3 dB power non-uniformity were 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.

QUANTUM CASCADE LASER

A quantum cascade laser is configured with a semiconductor substrate, and an active layer provided on a first surface of the substrate and having a multistage lamination of unit laminate structures each of which includes an emission layer and an injection layer. The active layer is configured to be capable of generating first pump light of a frequency ωand second pump light of a frequency ω, and to generate output light of a difference frequency ω by difference frequency generation. An external diffraction grating is provided constituting an external cavity for generating the first pump light and configured to be capable of changing the frequency ω, outside an element structure portion including the active layer. Grooves respectively formed in a direction intersecting with a resonating direction are provided on a second surface of the substrate. 1. A quantum cascade laser comprising:a semiconductor substrate; andan active layer provided on a first surface of the semiconductor substrate and having a cascade structure in which quantum well emission layers and injection layers are alternately stacked in the form of a multistage lamination of unit laminate structures each of which comprises the quantum well emission layer and the injection layer, wherein{'sub': 1', '2', '1', '2, 'the active layer is configured to be capable of generating first pump light of a first frequency ωand second pump light of a second frequency ωby intersubband emission transitions of electrons, and to generate output light of a difference frequency ω between the first frequency ωand the second frequency ωby difference frequency generation from the first pump light and the second pump light,'}{'sub': 1', '1, 'an external diffraction grating is provided constituting an external cavity for generating the first pump light by feeding the light of the first frequency ωback to an element structure portion and configured to be capable of changing the first frequency ω, outside the element structure ...

Wavelength beam combining laser systems utilizing etalons

In various embodiments, wavelength beam combining laser systems incorporate etalons to establish external lasing cavities and/or to combine multiple input beams into a single output beam.

Semiconductor laser beam combining device

A semiconductor laser beam combining device includes at least two modular laser input equipments, a second diffraction grating, and an output coupler. The modular laser input equipment includes a semiconductor laser, a beam shaping component, a transformation lens, and a first diffraction grating arranged along an optical path in sequence. The semiconductor laser generates a beam. The semiconductor laser is located at a front focal point of the transformation lens. The first diffraction grating is located in front of a back focal point of the transformation lens. Each beam is gathered by the transformation lens and diffracted by the first diffraction grating to the second diffraction grating. Each beam is combined at an identical position and an identical diffraction angle on the second diffraction grating to generate a combined beam. The combined beam from the second diffraction grating enters the output coupler vertically and is outputted by the output coupler.

STABILIZED DIODE LASER

A stabilized diode laser device is disclosed, which includes a unibody mounting plate that is mated mechanically to a thermoelectric cooler. The unibody mounting plate comprises chambers in which components, including a laser diode, are aligned and secured. A combination of the secured components within the unibody mounting plate, along with the thermoelectric cooler, provides stabilization of the laser diode. 1. A stabilized diode laser device comprising: a laser diode that is controlled to emit an output comprising light;', 'a collimating lens; and', 'a volume Bragg grating;, 'a housing containing a set of components, comprisingwherein:the laser diode, collimating lens, and volume Bragg grating are optically aligned such that the collimating lens causes an axis of light emitted by the laser diode to diverge at a controlled angle so that light that reaches the volume Bragg grating is spatially extended to match the laser diode;the volume Bragg grating is positioned to reflect a fraction of the light emitted by the laser diode over a narrow spectral range that interacts with the laser diode and stabilizes a laser diode output to match a reflection spectrum of the volume Bragg grating; andthe emitted output of the laser diode lases over a rectangular surface.3. The stabilized diode laser device of claim 1 , wherein the volume Bragg grating is optically aligned with the laser diode to reduce the laser diode spectral width by an order of magnitude of at least two.4. The stabilized diode laser device of claim 1 , wherein the collimating lens is a spherical lens.5. The stabilized diode laser device of claim 1 , wherein the housing comprises a stack up of single-axis translation and rotation stages associated with the set of components; 'a clamp that holds each component of the set of components in position.', 'further comprising6. The stabilized diode laser device of claim 5 , wherein the stack up of single-axis translation and rotation stages comprise five additional ...

EXTERNAL CAVITY LASER

Practical silicon-based light sources are still missing, despite the progress in germanium lasers, because both silicon and germanium are indirect-band semiconductors and inefficient at light generation. A tunable and single mode external cavity laser comprising: a gain medium for generating light between a reflective surface at one end of the gain medium; and a wavelength selective reflector at the other end of a laser cavity. A splitter disposed in the laser cavity includes an input port optically coupled to the gain medium, an input/output port optically coupled to the wavelength selective reflector, and an output port for outputting laser light at selected wavelengths. The wavelength selective reflector reflects light of one or more selected periodic wavelengths back to the gain medium via the input/output port, and passes light of non-selected wavelengths out of the laser cavity. 120-. (canceled)21. An external cavity laser comprising:a gain medium for generating light;a first reflector at one end of the gain medium with greater than 90% reflectivity;a coupler including an input port, an input/output port, and an output port, the input port optically coupled to the gain medium, wherein the coupler is configured to split the light from the gain medium into input laser light directed to the input/output port, and output laser light directed to the output port;a wavelength selective reflector optically coupled to the input/output port forming a laser cavity with the first reflector, and configured for returning the input laser light at a selected wavelength back to the gain medium via the input/output port, and passing non-selected light at non-selected wavelengths, wherein the coupler is also configured for directing the input laser light at the selected wavelength returning from the wavelength selective reflector to the gain medium;a first phase tuner between the coupler and the wavelength selective reflector configured for tuning an optical cavity length of the ...

Low cost external cavity diode lasers

External cavity diode laser (ECDL) devices and methods for producing the same are described that allows ECDLs to be readily produced and configured to operate at a desired range of wavelengths, while allowing tunability of the output wavelength. One ECDL includes a laser gain chip including a gain medium, a first reflective surface at a first end of the gain medium, and a second surface at a second end of the gain medium opposite to the first reflective surface. The second surface has a facet that forms an angle approximately equal to Brewster's angle for light having a first wavelength. The ECDL further includes a diffraction grating positioned to receive light that passes through the second surface, to operate as a mirror in the external cavity diode laser, and to allow a portion of the light to be directed outside of the external cavity diode laser as output light.

INHOMOGENEOUS FOCUSING AND BROADBAND METASURFACE QUANTUM-CASCADE LASERS

A reflectarray metasurface for quantum-cascade lasing includes: (1) a substrate; and (2) an array of subcavities disposed on the substrate. Each subcavity in the array of subcavities includes (a) a first metallic layer disposed on the substrate; (b) a layer of a quantum-cascade laser active material disposed on the first metallic layer; and (c) a second metallic layer disposed on the layer of the quantum-cascade laser active material. At least some subcavities in the array of subcavities have inhomogeneous widths, and the array of subcavities is configured to reflect an incident light of at least one resonant frequency with amplification. 1. A metasurface for quantum-cascade lasing , comprising:a substrate; and a first metallic layer disposed on the substrate;', 'a layer of a quantum-cascade laser active material disposed on the first metallic layer; and', 'a second metallic layer disposed on the layer of the quantum-cascade laser active material,, 'an array of subcavities disposed on the substrate, wherein each subcavity in the array of subcavities includeswherein at least some subcavities in the array of subcavities have inhomogeneous widths, and the array of subcavities is configured to reflect an incident light of at least one resonant frequency with amplification.2. The metasurface of claim 1 , wherein widths of subcavities at respective positions in the array of subcavities vary according to distances from a reference point of the metasurface to the respective positions.3. The metasurface of claim 1 , wherein a width of at least one subcavity varies along its lengthwise direction.4. The metasurface of claim 1 , wherein a width of at least one subcavity at respective positions along its lengthwise direction varies according to distances from a reference point of the metasurface to the respective positions.5. The metasurface of claim 1 , wherein widths of subcavities in the array of subcavities are spatially modulated so that a reflected light from the ...

HORIZONTAL EXTERNAL-CAVITY LASER GEOMETRY

An optoelectronic device includes a semiconductor substrate and a vertical-cavity surface-emitting laser (VCSEL) light source formed on the substrate and configured to emit coherent light at a predefined wavelength along a beam axis perpendicular to a surface of the substrate. A block of a transparent material is mounted on the surface of the substrate and forms, with the VCSEL, a resonant cavity at the predefined wavelength having an entrance face that is aligned with the beam axis and an exit face that is laterally displaced with respect to the entrance face along a cavity axis running parallel to the surface of the substrate. 1. An optoelectronic device , comprising:a semiconductor substrate;a vertical-cavity surface-emitting laser (VCSEL) light source formed on the substrate and configured to emit coherent light at a predefined wavelength along a beam axis perpendicular to a surface of the substrate; anda block of a transparent material comprising opposing first and second sides that are parallel to the surface of the substrate, such that the first side is adjacent to and mounted on the surface of the substrate, and the block of the transparent material forms, with the VCSEL, a resonant cavity at the predefined wavelength having an entrance face on the first side of the block of the transparent material that is aligned with the beam axis and an exit face on the second side of the block of the transparent material that is laterally displaced with respect to the entrance face along a cavity axis running between the first and second sides of the block of the transparent material in a direction parallel to the surface of the substrate.2. (canceled)3. The optoelectronic device of claim 1 , wherein the block of the transparent material comprises third and fourth sides claim 1 , not parallel to the first and second sides claim 1 , wherein the third side is configured to receive the emitted light through the entrance face and to reflect the received light along the ...

EXTERNAL RESONATOR TYPE LASER DEVICE

An external resonator type laser device has an optical element that forms an external resonator with a semiconductor device by selecting and reflecting light of a specific wavelength range from light outputted from the semiconductor device; a supporting member formed of a material having a larger coefficient of linear expansion than the optical element; and a first mount interposed between the optical element and the supporting member, formed of a material having a coefficient of linear expansion closer to that of the optical element compared with that of the supporting member. The optical element is adhered to the first mount. The first mount is adhered to the supporting member by an adhesive having a Shore hardness of less than or equal to 65. 1. An external resonator type laser device comprising:an optical element that forms an external resonator with a semiconductor device by selecting and reflecting light of a specific wavelength range from light outputted from the semiconductor device;a supporting member formed of a material having a larger coefficient of linear expansion than that of the optical element; anda first mount interposed between the optical element and the supporting member, formed of a material having a coefficient of linear expansion closer to that of the optical element compared with that of the supporting member, whereinthe optical element is adhered to the first mount, andthe first mount is adhered to the supporting member by an adhesive having a Shore hardness of less than or equal to 65.2. The external resonator type laser device according to claim 1 , whereinthe first mount is adhered to the supporting member by a thermosetting adhesive, andthe optical element is adhered to the first mount by a photocurable adhesive.3. The external resonator type laser device according to claim 2 , whereinthe optical element includes:a wavelength selection element that selects and reflects light of the specific wavelength range; anda second mount interposed ...

EXTERNAL CAVITY LASER WITH A PHASE SHIFTER

Systems and methods described herein are directed to optical light sources, such as an external cavity laser (ECL) with an active phase shifter. The system may include control circuity for controlling one or more parameters associated with the active phase shifter. The phase shifter may be a p-i-n phase shifter. The control circuitry may cause variation in a refractive index associated with the phase shifter, thereby varying a lasing frequency of the ECL. The ECL may be configured to operate as a light source for a light detection and ranging (LIDAR) system based on generating frequency modulated light signals. In some embodiments, the ECL may generate an output LIDAR signal with alternating segments of increasing and decreasing chirp frequencies. The ECL may exhibit increased stability and improved chirp linearities with less dependence on ambient temperature fluctuations. 1. A method for chirping a laser output wavelength , comprising:controlling, by a computing device, a laser drive current;selecting, by the computing device and based on the laser drive current, an initial voltage bias associated with a phase shifter element;analyzing, by the computing device, a chirp linearity associated with the laser output wavelength; andvarying, by the computing device and based on the chirp linearity, the initial voltage bias associated with the phase shifter element.2. The method of claim 1 , wherein the varying the initial voltage bias is based on:determining a linearity correction factor associated with the chirp linearity; andapplying the linearity correction factor to a waveform of the initial voltage bias.3. The method of claim 1 , further comprising:periodically monitoring the chirp linearity associated with the laser output wavelength;determining that the chirp linearity has satisfied a threshold linearity value;determining a modified voltage bias waveform based on the threshold linearity value; andapplying the modified voltage bias waveform to the phase shifter ...

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 , ...

Photonic circuit with hybrid iii-v on silicon active section with inverted silicon taper

A photonic circuit with a hybrid III-V on silicon or silicon-germanium active section, that comprises an amplifying medium with a III-V heterostructure ( 1 , QW, 2 ) and an optical wave guide. The wave guide comprises a coupling section ( 31 ) facing a central portion of the amplifying medium, a propagation section ( 34, 35 ) and a modal transition section ( 32, 33 ) arranged between the coupling section and the propagation section. In the modal transition section, the optical wave guide widens progressively from the propagation section towards the coupling section.

TWO-DIMENSIONAL MULTI-BEAM STABILIZER AND COMBINING SYSTEMS AND METHODS

A system and method for stabilizing and combining multiple emitted beams into a single system using both WBC and WDM techniques. 120-. (canceled)21. A method of stabilizing and combining an array of emitters each emitting a beam , the method comprising:forming a stabilizer cavity wherein each emitter forms a resonator with an external reflective surface to thereby stabilize the beam emitted by each emitter to a unique wavelength, wherein each beam emitted by the array of emitters is introduced to a dispersive element disposed within the resonator, wherein the dispersive element comprises a grating, a chirped grating, a surface grating, a volume grating, a transmission grating, or a prism;transmitting the beams of the stabilizer from the dispersive element into a wavelength combiner; andcombining the beams, within the wavelength combiner, along one dimension to form a multi-wavelength beam output.22. The method of claim 21 , wherein the beams of the stabilizer are transmitted into the wavelength combiner through back facets of the emitters.23. The method of claim 21 , wherein the beams of the stabilizer transmitted into the wavelength combiner do not pass through the emitters before entering the wavelength combiner.24. The method of claim 21 , wherein the wavelength combiner comprises at least one combining optical element.25. The method of claim 21 , wherein the multi-wavelength beam output is transmitted away from the array of emitters.26. The method of claim 21 , wherein the beams of the stabilizer transmitted into the wavelength combiner comprise the zero-order dispersion of the dispersive element.27. The method of claim 21 , wherein the dispersive element disperses the beams along only a single optical axis.28. The method of claim 21 , wherein the dispersive element is the external reflective surface.29. The method of claim 21 , wherein the external reflective surface receives a portion of the beams from the dispersive element to form the resonator.30. The ...

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.

DISTRIBUTED FEEDBACK SEMICONDUCTOR LASER

A distributed feedback semiconductor laser of includes a semiconductor stacked body and a first electrode. The semiconductor stacked body includes a first layer, an active layer that is provided on the first layer and is configured to emit laser light by an intersubband optical transition, and a second layer that is provided on the active layer. The semiconductor stacked body has a first surface including a flat portion and a trench portion; the flat portion includes a front surface of the second layer; the trench portion reaches the first layer from the front surface; the flat portion includes a first region and a second region; the first region extends along a first straight line; the second region extends to be orthogonal to the first straight line; and the trench portion and the second region outside the first region form a diffraction grating having a prescribed pitch along the first straight line. The first electrode is provided in the first region. 1. A distributed feedback semiconductor laser , comprising:a semiconductor stacked body including a first layer, an active layer, and a second layer, the active layer being provided on the first layer and being configured to emit laser light by an intersubband optical transition, the second layer being provided on the active layer; anda first electrode,the semiconductor stacked body having a first surface including a flat portion and a trench portion, the flat portion including a front surface of the second layer, the trench portion reaching the first layer from the front surface, the flat portion including a first region and a second region, the first region extending along a first straight line, the second region extending to be orthogonal to the first straight line, the trench portion and the second region outside the first region forming a diffraction grating having a prescribed pitch along the first straight line, andthe first electrode being provided in the first region.2. The distributed feedback ...

External Resonator-Type Light Emitting Device

An external resonator type light emitting system includes a light source oscillating a semiconductor laser light and a grating device providing an external resonator with the light source. The light source includes an active layer oscillating the semiconductor laser light. The grating device includes an optical waveguide having an incident face to which the semiconductor laser is incident and an emitting face of emitting an emitting light of a desired wavelength, a Bragg grating formed in the optical waveguide, and a propagating portion provided between the incident face and the Bragg grating. Formulas (1) to (4) are satisfied. 1. An external resonator type light emitting system comprising a light source oscillating a semiconductor laser light and a grating device providing an external resonator with said light source;wherein said light source comprises an active layer oscillating said semiconductor laser light;wherein said grating device comprises an optical waveguide comprising an incident face to which said semiconductor laser light is incident and an emitting face of emitting an emitting light having a desired wavelength, a Bragg grating formed in said optical waveguide, and a propagating portion provided between said incident face and said Bragg grating;wherein said optical waveguide comprises a core; [{'br': None, 'sub': 'G', 'Δλ≧0.8 nm\u2003\u2003(1)'}, {'br': None, 'i': 'L', 'sub': 'b', '≦500 μm\u2003\u2003(2)'}, {'br': None, 'i': 'L', 'sub': 'a', '≦500 μm\u2003\u2003(3)'}, {'br': None, 'i': 'n', 'sub': 'b', '≧1.8\u2003\u2003(4)'}], 'wherein the following formulas (1) to (4) are satisfied.'}, 'wherein a cross section of said core is of a convex shape; and'}{'sub': 'G', 'claim-text': [{'sub': 'b', 'Lrepresents a length of said Bragg grating in said formula (2).'}, {'sub': 'a', 'Lrepresents a length of said active layer in said formula (3).'}, {'sub': 'b', 'nrepresents a refractive index of a material forming said Bragg grating in said formula (4).)'}], '(Δλ ...

GENERATION OF HIGH-POWER SPATIALLY-RESTRUCTURABLE SPECTRALLY-TUNABLE BEAMS IN A MULTI-ARM-CAVITY VECSEL-BASED LASER SYSTEM

A collinear T-cavity VECSEL system generating intracavity Hermite-Gaussian modes at multiple wavelengths, configured to vary each of these wavelengths individually and independently. A mode converter element and/or an astigmatic mode converter is/are aligned intracavity to reversibly convert the Gaussian modes to HG modes to Laguerre-Gaussian modes, the latter forming the system output having any of the wavelengths provided by the spectrum resulting from nonlinear frequency-mixing intracavity (including generation of UV, visible, mid-IR light). The laser system delivers Watt-level output power in tunable high-order transverse mode distribution. 1. A laser source comprising:a laser cavity network including first and second spatially-distinct cavity arms and a collinear portion, wherein the first and second spatially-distinct cavity arms share the collinear portion, a corresponding gain medium that includes one of (i) a VECSEL-based laser gain medium, (ii) a solid-state gain medium, and (iii) a fiber amplifier and that is configured to provide amplification of light at a corresponding wavelength;', 'and', 'at least one of a first optical system, disposed across an axis of the at least one of the first and second cavity arms to either refract or reflect light incident thereon while transforming a transverse distribution of said light that has traversed it, and', 'a second optical system, disposed across said axis between the corresponding gain medium and the collinear portion and characterized by optical losses at the corresponding wavelength;, 'at least one of the first and second cavity arms containing, intracavity,'} a first transverse mode distribution in a first portion of the laser cavity network between the corresponding gain medium and the second optical system,', 'a second transverse mode distribution in a second portion of the laser cavity network between the second optical system and the collinear portion, and', 'a third transverse mode distribution in a ...

Optical measurement device, optical measurement method, and rotary machine

The present invention includes: a laser that can change the emission wavelength of light; a light-emitting fiber that emits light output from the laser onto a rotor; a concave surface that is provided in a recessed manner in the rotor and reflects the light emitted from the light-emitting fiber; a light-receiving fiber that receives the light reflected by the concave surface; a photodetector that detects the intensity of the light received by the light-receiving fiber; and a control device that controls the laser and performs optical measurement. The intensity is detected by the photodetector while changing the emission wavelength of the laser; the emission wavelength at which the intensity is largest is selected; and optical measurement is performed by detecting the intensity of light reflected by the concave surface by using light having an emission angle determined by the selected emission wavelength.

VARIABLE CONFINEMENT HYBRID OSCILLATOR POWER AMPLIFIER

Described herein is a two chip photonic device (e.g., a hybrid master oscillator power amplifier (MOPA)) where a gain region and optical amplifier region are formed on a III-V chip and a variable reflector (which in combination with the gain region forms a laser cavity) is formed on a different semiconductor chip that includes silicon, silicon nitride, lithium niobate, or the like. Sides of the two chips are disposed in a facing relationship so that optical signals can transfer between the gain region, the variable reflector, and the optical amplifier. 1. A photonic device , comprising: a gain region configured to generate an optical signal;', 'an optical amplifier configured to amplify the optical signal;, 'a III-V semiconductor chip comprisinga substrate separate from the III-V semiconductor, the substrate comprising a variable reflector, wherein an input of the variable reflector is optically coupled to an output of the gain region and an output of the variable reflector is optically coupled to an input of the optical amplifier.2. The photonic device of claim 1 , further comprising a high reflective (HR) element disposed at a first end of the gain region that is opposite a second end of the gain region that is optically coupled to the variable reflector.3. The photonic device of claim 2 , wherein the HR element claim 2 , the gain region claim 2 , and the variable reflector form a cavity for a laser.4. The photonic device of claim 1 , wherein the output of the gain region and the input of the optical amplifier are optically coupled to a same facet of the III-V semiconductor chip claim 1 , and wherein the input and the output of the variable reflector are coupled to a same facet of the substrate.5. The photonic device of claim 1 , further comprising:a first supermode filtering waveguide (SFW) disposed in the gain region; anda second SFW disposed in the optical amplifier, wherein the first and second SFWs comprises a first optical waveguide formed in a ridge that is ...

Hybrid Silicon Lasers on Bulk Silicon Substrates

Hybrid silicon lasers are provided including a bulk silicon substrate, a localized insulating layer that extends on at least a portion of the bulk silicon substrate, an optical waveguide structure on an upper surface of the localized insulating layer. The optical waveguide structure includes an optical waveguide including a silicon layer. A lasing structure is provided on the optical waveguide structure.

DFB WITH WEAK OPTICAL FEEDBACK

A distributed feedback plus reflection (DFB+R) laser includes an active section, a passive section, a low reflection (LR) mirror, and an etalon. The active section includes a distributed feedback (DFB) grating and is configured to operate in a lasing mode. The passive section is coupled end to end with the active section. The LR mirror is formed on or in the passive section. The etalon includes a portion of the DFB grating, the passive section, and the LR mirror. The lasing mode of the active section is aligned to a long wavelength edge of a reflection peak of the etalon.

TUNABLE LASER FOR COHERENT TRANSMISSION SYSTEM

A tunable laser device is described. In one example, the tunable laser device includes an adaptive ring mirror, a gain waveguide, a loop mirror waveguide, and a booster amplifier waveguide. The gain waveguide and the boost amplifier waveguide can be formed in a semiconductor optical amplifier (SOA) region of the tunable laser device, and the adaptive ring mirror and the loop mirror waveguide can be formed in a silicon photonics region of the tunable laser device. The adaptive ring mirror includes a phase shifter optically coupled between a number of MMI couplers. By inducing a phase shift using the phase shifter, the wavelength of the output of the tunable laser device can be altered or adjusted for use in coherent fiber-optic communications, for example, among other applications. 1. A tunable laser device , comprising:an adaptive ring mirror;a gain waveguide optically coupled to the adaptive ring mirror;a loop mirror optically coupled to the gain waveguide; anda booster amplifier optically coupled to the loop mirror at one end and adapted to provide a laser output of the tunable laser device at another end, wherein:the gain waveguide and the boost amplifier are formed in a semiconductor optical amplifier (SOA) region of the tunable laser device; andthe adaptive ring mirror and the loop mirror are formed in a silicon photonics region of the tunable laser device.2. The tunable laser device of claim 1 , wherein the adaptive ring mirror comprises:a number of multimode interference (MMI) couplers each comprising a single input, double output MMI coupler, wherein:a first output of a first MMI coupler among the MMI couplers is optically coupled to an input of a second MMI coupler among the MMI couplers; anda second output of the first MMI coupler is optically coupled to an input of a third MMI coupler among the MMI couplers.3. The tunable laser device of claim 2 , wherein the adaptive ring mirror further comprises:a number of linear waveguides optically coupled to outputs ...

EXTERNAL CAVITY TYPE TUNABLE WAVELENGTH LASER MODULE FOR TO-CAN PACKAGING

Provided is a tunable wavelength laser module including: an external cavity type light source generating broadband light; an optical waveguide; a Bragg grating formed in the optical waveguide; a heater provided above the optical waveguide in which the Bragg grating is formed and adjusting a reflection band of the Bragg grating by a thermo-optic effect; a direction change waveguide region changing direction of optical signals obtained by the adjusted reflection band of the Bragg grating, by a predetermined angle; a -degree reflection part transmitting some of the optical signals direction-changed by the direction change waveguide region and escaping from the optical waveguide therethrough and reflecting the others of the optical signals in a vertical upward direction thereby; and a lens making the optical signals reflected in the vertical upward direction by the -degree reflection part collimated light or convergent light. 1. An external cavity type tunable wavelength laser module comprising:an external cavity type light source generating broadband light;an optical waveguide to which the broadband light output from the light source is input;a Bragg grating formed in the optical waveguide;a heater provided above the optical waveguide in which the Bragg grating is formed and adjusting a reflection band of the Bragg grating by a thermo-optic effect;a direction change waveguide region changing direction of optical signals obtained by the adjusted reflection band of the Bragg grating, by a predetermined angle, to output direction-changed optical signals;a 45-degree reflection part transmitting some of the direction-changed optical signals escaping from the optical waveguide therethrough and reflecting a remainder of the direction-changed optical signals in a vertical upward direction thereby; anda lens making the direction-changed optical signals reflected in the vertical upward direction by the 45-degree reflection part collimated light or convergent light.2. The ...

EXTERNAL-RESONATOR-TYPE LIGHT-EMITTING DEVICE

An external resonator type light-emitting device includes a light source oscillating a semiconductor laser light and a grating element configuring an external resonator together with the light source. The light source includes an active layer oscillating the semiconductor laser light. The grating element includes an optical waveguide and a plurality of Bragg gratings formed in the optical waveguide. The optical waveguide includes an incident face on which the semiconductor laser light is incident and an emitting face from which an emitting light having a desired wavelength is emitted. 1. An external resonator type light-emitting device comprising a light source oscillating a semiconductor laser light and a grating element configuring an external resonator together with said light source:wherein said light source comprises an active layer oscillating said semiconductor laser light; andwherein said grating element comprises an optical waveguide and a plurality of Bragg gratings formed in said optical waveguide,said optical waveguide comprising an incident face to which said semiconductor laser light is incident and an emitting face from which an emitting light having a desired wavelength is emitted,2. The device of claim 1 ,wherein said Bragg gratings have wavelength regions, respectively, in which reflectances of said Bragg gratings are higher than a reflectance at an emitting end of said light source, respectively; andwherein said wavelength regions of said Bragg gratings having central wavelengths adjacent to each other are continuous.3. The device of claim 2 ,wherein said reflectances of said Bragg gratings having said central wavelengths adjacent to each other are equal to each other at predetermined wavelengths, respectively, andwherein a minimum value of a grating reflectance necessary for laser oscillation in an external resonator mode is not less than said reflectance at said emitting end of said light source, and is not more than each of said reflectances of ...

EXTERNAL-RESONATOR-TYPE LIGHT-EMITTING DEVICE

An external resonator type light-emitting device includes a light source oscillating a semiconductor laser light and a grating element configuring an external resonator together with the light source. The light source includes an active layer oscillating said semiconductor laser light. The grating element includes an optical waveguide and a plurality of Bragg gratings formed in the optical waveguide. The optical waveguide includes an incident face to which the semiconductor laser light is incident and an emitting face from which an emitting light having a desired wavelength is emitted. A half value reflectance Ris larger than a reflectance Rat an emitting end of the light source. A half value reflectance Ris 3% or larger. A combined reflectance is not less than the half value reflectance Rin a wavelength region Δλ. The wavelength region Δλis continuous over 10 nm or more and 30 nm or less, provided that a half value reflectance is defined as 50 percent of a maximum value Rmax of the combined reflectance of the Bragg gratings. 1. An external resonator type light-emitting device comprising a light source oscillating a semiconductor laser light and a grating element configuring an external resonator together with said light source:wherein said light source comprises an active layer oscillating said semiconductor laser light;wherein said grating element comprises an optical waveguide and a plurality of Bragg gratings formed in said optical waveguide, said optical waveguide comprising an incident face to which said semiconductor laser light is incident and an emitting face from which an emitting light having a desired wavelength is emitted, and said Bragg gratings having periods different from each other;{'sub': 50', '2, 'wherein a half value reflectance Ris larger than a reflectance Rat an emitting end of said light source;'}{'sub': '50', 'wherein said half value reflectance Ris 3% or larger; and'}{'sub': 50', '50', '50', '50, 'wherein a combined reflectance of said ...

External cavity with a pair of two Fiber Bragg gratings at the front and back facet of a laser diode

A semiconductor laser chip is placed in between two Fiber Bragg gratings (FBGs), which are used as external cavities for the laser, to stabilize its center wavelength and to reduce its bandwidth. The first FBG is placed at the front facet of the laser chip, while the second FBG is placed on the back facet of the chip. The two FBGs are used to form an external cavity. Both FBGs can have same central wavelengths, different reflectivities and different bandwidths. The distance between the laser chip and the FBGs can varies from few millimeters to several meters. Since the FBGs have a very small wavelength drift with temperature fluctuations, the semiconductor laser has a stable center wavelength output. Another benefit of this setup is that the bandwidth of laser diode is also reduced.

THERMO-OPTICALLY TUNABLE LASER SYSTEM

A tunable laser has a solid state laser medium having an optical gain region and generates coherent radiation through a facet. A lens collects the coherent radiation and generates a collimated light beam. Components of an external cavity include a reflective surface and an optical filter, the reflective surface reflecting the collimated beam back to the lens and the laser medium, the optical filter positioned between the reflective surface and the lens and having two surfaces with a thermally tunable optical transmission band within the optical gain region of the laser medium. The optical filter (1) transmits a predominant portion of the collimated beam at a desired wavelength of operation, and (2) specularly reflects a remaining portion of the collimated beam from each surface, the collimated beam being incident on the optical filter such that the reflected collimated beams propagate at a non-zero angle with respect to the incident collimated beam. 2. The tunable laser of claim 1 , wherein the pulse of the laser medium coherent optical signal is created by an electronic pulse with a low duty cycle and optical power of the tunable laser output increases following the pulse.3. The tunable laser of claim 1 , wherein the optical gain region of the solid state laser medium has a wavelength region of lower optical gain interspersed between wavelength regions of higher optical gain.4. The tunable laser of wherein the wavelength selection device is an etalon with a free spectral range and a width of the wavelength region of higher optical gain is less than the free spectral range.5. A method of tuning an external cavity semiconductor laser claim 3 , comprising:(1) setting a first operating condition of a wavelength selection device within the external cavity to select a first optical feedback selection wavelength and a first lasing wavelength of continuous wave laser operation,(2) changing to a second operating condition of the wavelength selection device within the ...

DFB WITH WEAK OPTICAL FEEDBACK

A distributed feedback plus reflection (DFB+R) laser includes an active section, a passive section, a low reflection (LR) mirror, and an etalon. The active section includes a distributed feedback (DFB) grating and is configured to operate in a lasing mode. The passive section is coupled end to end with the active section. The LR mirror is formed on or in the passive section. The etalon includes a portion of the DFB grating, the passive section, and the LR mirror. The lasing mode of the active section is aligned to a long wavelength edge of a reflection peak of the etalon. 1. A distributed feedback plus reflection (DFB+R) laser , comprising:a distributed feedback (DFB) section configured to operate in a lasing mode;a high reflection (HR) mirror coupled to a rear of the DFB section;a passive section coupled to a front of the DFB section; anda low reflection (LR) mirror formed at a front of the passive section;wherein the passive section, a portion of the DFB section at the front of the DFB section, and the LR mirror form an etalon having a reflection profile with periodic peaks and valleys, and wherein the lasing mode of the DFB section is aligned to a long wavelength edge of one of the periodic peaks of the reflection profile of the etalon.2. The DFB+R laser of claim 1 , wherein the LR mirror has a reflectivity of 15% or less.3. The DFB+R laser of claim 1 , wherein the LR mirror has a reflectivity of 10% or less.4. The DFB+R laser of claim 1 , wherein the passive section is configured to impart a phase shift of about 20 degrees to light propagating in the DFB+R laser.5. The DFB+R laser of claim 1 , wherein the HR mirror has a reflectivity of 30% or more.6. The DFB+R laser of claim 1 , further comprising a modulation contact coupled to the DFB section and configured to provide a modulation signal to the DFB section to modulate the DFB section claim 1 , wherein modulation of the DFB section modulates cavity loss of the DFB+R laser and increases carrier-photon resonance ...

ISOLATOR-FREE LASER

An isolator-free laser includes an etalon, an active section, and a low reflection (LR) mirror. The etalon includes a passive section of the isolator-free laser and a reflection profile. The active section is coupled end to end with the passive section. The active section has a distributed feedback (DFB) grating and a lasing mode at a long wavelength side of a reflection peak of the reflection profile. The LR mirror is formed on a front facet of the passive section. The long wavelength edge of the reflection peak of the reflection profile may have a slope greater than 0.006 GHz. A RIN of the isolator-free laser under −20 decibels (dB) external cavity optical feedback may be less than or equal to −130 dBc/Hz. 1. An isolator-free laser , comprising:an etalon, the etalon comprising a passive section of the isolator-free laser and a reflection profile;{'sup': −1', '−1, 'an active section coupled end to end with the passive section, the active section having a distributed feedback (DFB) grating and a lasing mode at a long wavelength edge of a reflection peak of the reflection profile, the long wavelength edge of the reflection peak of the reflection profile having a slope greater than 0.006 gigahertz(GHz) at the lasing mode; and'}a low reflection (LR) mirror formed on a front facet of the passive section;wherein a relative intensity noise (RIN) of the isolator-free laser under −20 decibels (dB) external cavity optical feedback is less than or equal to −130 dBc/Hz.2. The isolator-free laser of claim 1 , wherein the RIN of the isolator-free laser under −10 dB external cavity optical feedback is less than or equal to −130 dBc/Hz.3. The isolator-free laser of claim 1 , wherein the RIN of the isolator-free laser under −5 dB external cavity optical feedback is less than or equal to −130 dBc/Hz.4. The isolator-free laser of claim 1 , wherein the RIN of the isolator-free laser under −20 dB external cavity optical feedback is less than or equal to −155 dBc/Hz.5. The isolator-free ...

WAVELENGTH BEAM COMBINING LASER SYSTEMS UTILIZING ETALONS

In various embodiments, wavelength beam combining laser systems incorporate etalons to establish external lasing cavities and/or to combine multiple input beams into a single output beam. 114.-. (canceled)15. A laser system comprising:an array of beam emitters each emitting a beam, the beams being emitted substantially parallel to each other in a propagation direction;an etalon for receiving the beams and combining the beams into a multi-wavelength beam, the etalon having an optical axis, a front surface, and a back surface optically downstream of the front surface;disposed optically downstream of the beam emitters and optically upstream of the etalon, focusing optics for focusing the beams toward the etalon; anda partially reflective output coupler for receiving the multi-wavelength beam, reflecting a first portion thereof back toward the etalon, and transmitting a second portion thereof as an output beam composed of multiple wavelengths.16. The laser system of claim 15 , further comprising collimation optics disposed optically downstream of the etalon and optically upstream of the partially reflective output coupler.17. The laser system of claim 15 , wherein the front surface of the etalon is substantially parallel to the back surface of the etalon.18. The laser system of claim 15 , wherein the etalon comprises at least one of glass claim 15 , sapphire claim 15 , or fused silica.19. The laser system of claim 15 , wherein the output coupler comprises at least one of a mirror claim 15 , a volume Bragg grating claim 15 , or a fiber Bragg grating.20. The laser system of claim 15 , wherein the optical axis of the etalon is tilted at a non-zero angle with respect to the propagation direction.21. The laser system of claim 15 , wherein the front surface of the etalon is partially reflective to the beams.22. The laser system of claim 21 , wherein a reflectivity of the front surface of the etalon to the beams is greater than approximately 75% but less than 100%.23. The ...

LASER DIODE ENHANCEMENT DEVICE

The subject invention includes a semiconductor laser with the laser having a DBR mirror on a substrate, a quantum well on the DBR mirror, and an interior CGH with a back propagated output for emitting a large sized Gaussian and encircling high energy. The DBR mirror has a plurality of GaAs/AlGaAs layers, while the quantum well is composed of AlGaAs/InOaAs. The CGH is composed of AlGaAs. 1. The laser of claim 15 , the laser further including a DBR mirror and at least one quantum well in the DBR mirror.2. The laser of claim 1 , including a laser beam output that is back propagated for emitting a large sized Gaussian beam with high encircled energy.3. The laser of claim 1 , wherein the DBR mirror has a plurality of GaAs/AlGaAs layers.4. The laser of wherein the quantum well is composed of AlGaAs/InGaAs.5. The laser of wherein the CGH comprises GaAs/AlGaAs.6. (canceled)7. The laser of wherein there are at least 20 cascaded CGHs.8. The laser of wherein there are more than 20 cascaded CGHs.9. The laser of where each CGH comprises GaAs/AlGaAs.10. (canceled)11. The laser of having a laser gain medium that is semiconductor.12. The laser of having a laser gain medium that is crystal.13. The laser of having a laser gain medium that is gas.14. A vertical cavity surface emitting semiconductor laser claim 15 , with an intra-cavity wavefront shaping device comprising a plurality of CGHs at one end of the cavity claim 15 , with each CGH having a plurality of cascaded layers with a buffer layer between each cascaded layer.15. A vertical cavity surface emitting semiconductor laser claim 15 , comprising a plurality of wavefront shaping devices claim 15 , within a cavity said wavefront shaping devices being diffractive elements consisting of a plurality of interior CGHs at an end of the cavity; said CGHs each having a plurality of cascaded layers with a buffer layer between each layer.16. The device of wherein the diffractive elements comprises 2-20 layers of AlGaAs with buffer layers ...

ADJUSTMENT IMAGE GENERATING DEVICE, ADJUSTMENT IMAGE GENERATING METHOD, AND STORAGE MEDIUM HAVING PROGRAM STORED THEREIN

An adjustment image for facilitating adjustment is generated. An image display device according to an embodiment of the invention includes a semiconductor laser, a wheel, an adjustment image generating unit, and a projection unit. The semiconductor laser emits light. The wheel includes a first area and a second area as areas for adjusting color components of the light emitted from the semiconductor laser. The adjustment image generating unit generates an adjustment image in which a first color formed using a section adjacent to a boundary between the first area and the second area and a second color formed not using the section adjacent to the boundary and having color components close to the first color are arranged adjacent to each other. The projection unit projects the adjustment image generated by the adjustment image generating unit. 2. The adjustment image generating device according to claim 1 , wherein the processor is configured to:select colors which are different by one gradation in color components adjusted in the first area and the second area respectively, as the first color and the second color and generates the adjustment image.3. The adjustment image generating device according to claim 1 , wherein the processor is configured to:generate an adjustment image in which the first color on the first area side using a section on the first area side adjacent to the boundary and the second color on the first area side not using a section on the first area side adjacent to the boundary are arranged as a first color set andthe first color on the second area side using a section on the second area side adjacent to the boundary and the second color on the second area side not using a section on the second area side adjacent to the boundary are arranged as a second color set to be closer to the first color set.4. The adjustment image generating device according to claim 2 , wherein the processor is configured to:generate an adjustment image in which the first ...

MODULATING SPECTROSCOPIC IMAGING SYSTEM USING SUBSTANTIALLY COHERENT ILLUMINATION

A spectral imaging device () for generating an image (A) of a sample () includes (i) an image sensor (); (ii) a tunable light source () that generates an illumination beam () that is directed at the sample (); (iii) an optical assembly () that collects light from the sample () and forms an image of the sample () on the image sensor (); and (iv) a control system () that controls the tunable light source () and the image sensor (). During a time segment, the control system () (i) controls the tunable light source () so that the illumination beam () has a center wavenumber that is modulated through a first target wavenumber with a first modulation rate; and (ii) controls the image sensor () to capture at least one first image at a first frame rate. Further, the first modulation rate is equal to or greater than the first frame rate. 1. A spectral imaging device for generating an image of a sample , the spectral imaging device comprising:an image sensor that captures information of the image;a tunable light source that generates an illumination beam that is directed at the sample;an optical assembly that collects light from the sample and images the light on the image sensor; anda control system that controls the tunable light source and the image sensor; wherein, during a first time segment, the control system (i) controls the tunable light source so that the illumination beam includes a first beam set in which a center wavenumber of the illumination beam is modulated through a first target wavenumber with a first modulation rate; and (ii) controls the image sensor to capture at least one first image at a first frame rate; wherein the first modulation rate is equal to or greater than the first frame rate.2. The spectral imaging device of wherein the first modulation rate is approximately an integer multiple of the first frame rate.3. The spectral imaging device of wherein claim 2 , during a second time segment that is different from the first time segment claim 2 , the ...

Optical transmission device

An optical transmission device includes a semiconductor laser chip in which a semiconductor laser array having a plurality of distributed feedback semiconductor lasers formed on a first semiconductor substrate is formed, a semiconductor waveguide chip in which a semiconductor modulator array formed on a second semiconductor substrate and having the same number of semiconductor modulators as the semiconductor lasers is formed. In the optical transmission device, a waveguide and a waveguide are butt-joined such that a distance between an end face of the waveguide on a side to the semiconductor modulator array in each of the semiconductor lasers of the semiconductor laser array and an end face of the waveguide on a side to the semiconductor laser array in each of the semiconductor modulators of the semiconductor modulator array is 10 μm or less.

Silicon-On-Insulator Platform for Integration of Tunable Laser Arrays

An apparatus comprising a silicon-on-insulator (SOI) platform comprising an optical component network. An apparatus comprising an optical component network monolithically grown on a SOI platform, and an optical device coupled to the optical component network. A method comprising generating an optical signal using a silicon-based optical component, applying an electrical signal to the optical component, and tuning a wavelength of the optical signal based on the electrical signal.

SINGLE-MODE REFLECTOR USING A NANOBEAM CAVITY

An integrated circuit includes an optical reflector with one or two bus optical waveguides and a one-dimensional, photonic crystal nanobeam cavity to provide single-mode reflection with a narrow bandwidth. In particular, the nanobeam cavity may be implemented on a nanobeam-cavity optical waveguide (such as a channel or ridge optical waveguide), which is optically coupled to the one or two bus optical waveguides. The nanobeam-cavity optical waveguide may include notches along a symmetry axis of the nanobeam-cavity optical waveguide that are partially etched from edges of the nanobeam-cavity optical waveguide toward a center of the nanobeam-cavity optical waveguide. Furthermore, a fill factor of the notches may vary as a function of location along the symmetry axis, while a pitch of the notches is unchanged, to define the nanobeam cavity. 1. An integrated circuit , comprising:a substrate;a buried-oxide (BOX) layer disposed on the substrate; and a nanobeam-cavity optical waveguide optically coupled to the first bus optical waveguide, wherein the nanobeam-cavity optical waveguide includes notches along a symmetry axis of the nanobeam-cavity optical waveguide that are partially etched from edges of the nanobeam-cavity optical waveguide toward a center of the nanobeam-cavity optical waveguide; and', 'wherein a fill factor of the notches varies as a function of location along the symmetry axis, while a pitch of the notches is unchanged, to define a nanobeam cavity., 'a first bus optical waveguide; and'}, 'a semiconductor layer disposed on the BOX layer, wherein the semiconductor layer includes an optical reflector, and wherein the optical reflector includes2. The integrated circuit of claim 1 , wherein the nanobeam-cavity optical waveguide includes one of: a ridge optical waveguide claim 1 , and a channel optical waveguide.3. The integrated circuit of claim 1 , wherein the first bus optical waveguide is curved.4. The integrated circuit of claim 1 , wherein tapering of the ...

Optical reflector based on a directional coupler and a coupled optical loop

An optical device includes an optical reflector based on a coupled-loopback optical waveguide. In particular, an input port, an output port and an optical loop in arms of the optical reflector are optically coupled to a directional coupler. The directional coupler evanescently couples an optical signal between the arms. For example, the directional coupler may include: a multimode interference coupler and/or a Mach-Zehnder Interferometer (MZI). Moreover, destructive interference during the evanescent coupling determines the reflection and transmission power coefficients of the optical reflector.

OPTICAL KIT AND OPTICAL DEVICE

An optical kit includes a base including a main surface; and a holding unit provided on the main surface to hold an optical system. The holding unit includes a lens holding unit that holds a lens, a reflector holding unit that holds a corner reflector, a first aperture member holding unit that holds a first aperture member, a second aperture member holding unit that holds a second aperture member, and a third aperture member holding unit that holds a third aperture member. The reflector holding unit includes a first mechanism that holds an entirety of the corner reflector so as to be rotatable along the main surface, and a second mechanism configured to adjust an optical axis of a diffracted light in each of a reflective diffraction grating and a mirror. 1. An optical kit forming an optical system including an external resonator of a laser light source that outputs a laser light , the kit comprising:a base including a main surface; anda holding unit provided on the main surface and configured to hold the optical system,wherein the optical system includes a lens into which the laser light is input in a first direction,a corner reflector including a reflective diffraction grating configured to reflect a diffracted light of the laser light, which has passed through the lens, in a second direction intersecting the first direction, and a mirror configured to reflect the diffracted light from the reflective diffraction grating in a third direction opposite to the first direction,a first aperture member disposed to form an optical aperture through which the laser light which has passed through the lens passes when the corner reflector is not installed, anda second aperture member and a third aperture member arranged in the third direction to form optical apertures through which the diffracted light from the corner reflector passes in order,the holding unit includes a lens holding unit configured to hold the lens,a reflector holding unit configured to hold the corner ...

Semiconductor optical device and method for producing semiconductor optical device

A semiconductor optical device includes a substrate containing silicon and having a waveguide, a first semiconductor element including a core layer formed of III-V group compound semiconductors and being bonded to the substrate, and a second semiconductor element including a diffraction grating and being bonded to the substrate, wherein the diffraction grating has a first semiconductor layer and a second semiconductor layer burying the first semiconductor layer, the first semiconductor layer and the second semiconductor layer are formed of III-V group compound semiconductors, and the diffraction grating reflects light propagating through the waveguide.

Broadband wavelength-swept light source system and apparatus employing the same

A light source system includes: a plurality of gain mediums configured to output a corresponding plurality of lights having different center wavelengths from each other; a first light source part configured to connect the plurality of gain mediums to each other in parallel and emit the plurality of lights; a wavelength-swept filter unit configured to sweep wavelengths of the plurality of lights output by the plurality of gain mediums and compensate for spectroscopic optical paths of the plurality of lights; a second light source part configured to connect the first light source part to the wavelength-swept filter unit in series and feed the wavelength-swept lights back to the plurality of gain mediums; a combiner configured to combine the wavelength-swept lights and output a combined wavelength-swept; and a controller configured to control an output magnitude and a wavelength region of the wavelength-swept lights.

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 ...

External resonance-type laser module

An external resonance-type laser module includes: a quantum cascade laser; a MEMS diffraction grating including a movable portion capable of swinging around an axis and a diffraction grating portion formed on the movable portion; a lens; a magnet; and a yoke. The MEMS diffraction grating includes a pair of coils respectively disposed on one side and the other side with respect to the axis when viewed in a normal direction parallel to a normal line of the diffraction grating portion, and each of the pair of coils includes an inside part extending along the axis. A recess portion is formed in the magnet, and at least a part of the recess portion overlaps the inside part when viewed in the normal direction.

BEAM COMBINING DEVICE AND BEAM COMBINING METHOD FOR BRAGG GRATING EXTERNAL-CAVITY LASER MODULE

A beam combining device and method for a Bragg grating external-cavity laser module has a plurality of side by side light-emitting modules that use a Bragg grating to perform wavelength locking. Output light of the modules is incident to a beam combining element after passing through a focusing optical element for beam combining, and light subjected to beam combining is reflected partially and transmitted partially under the effect of a light splitting element. A part is incident into a dispersion element at a diffraction angle of the element. Parallel light is formed under the effect of a conversion optical element. Spots of the light beams of corresponding wavelengths of the light-emitting modules are formed on an image acquisition mechanism. Whether the wavelengths of the corresponding light-emitting modules are locked is determined by whether there is a deviation between preset spots and spots formed by the module on the acquisition mechanism. 1. A beam combining device for a Bragg grating external-cavity laser module , comprising: at least two light-emitting modules arranged side by side at intervals , wherein any one of the light-emitting modules comprises a laser unit and a Bragg grating configured to receive laser emitted by the laser unit , and one light-emitting module serves as a reference light-emitting module; a focusing optical element arranged on an output optical path of all the light-emitting modules; and a beam combining element arranged on the focusing position of the output optical path of the focusing optical element; and further comprising:a light splitting element, arranged on an output optical path of the beam combining element;a dispersion element, arranged on any one of the output optical paths of the light splitting element, and configured to disperse beam combining light into dispersed light consistent with a relative positional relationship of the laser of each wavelength between the focusing optical element and the beam combining ...

External resonant laser module

The laser module includes a QCL element, a MEMS diffraction grating, a lens holder for holding a lens disposed between the QCL element and the MEMS diffraction grating, and a package. The package includes a bottom wall, a side wall erected on the bottom wall and formed in an annular shape so as to surround a region in which the QCL element is accommodated, and a top wall closing an opening of the side wall on a side opposite to a side where the bottom wall is disposed. The top wall faces the bottom wall in a direction orthogonal to the optical axis direction of the lens, and the distance between the top wall and a surface of the lens holder on a side where the top wall is disposed is smaller than a thickness of the lens holder along the optical axis direction of the lens.

External resonant laser module

The laser module includes a QCL element, a MEMS diffraction grating, a lens holder holding a lens disposed between the QCL element and the MEMS diffraction grating, a package, an electrode terminal disposed along an inner wall surface of the package, and a wire for electrically connecting the electrode terminal and a coil. The top wall of the package faces the bottom wall of the package in a direction orthogonal to the optical axis direction of the lens. The MEMS diffraction grating includes an electrode pad electrically connected to the coil. The electrode pad is connected to the electrode terminal via the wire. A height position of the electrode pad with respect to the bottom wall is equal to or higher than a height position of the electrode terminal with respect to the bottom wall.

METHOD AND SYSTEM FOR HYBRID INTEGRATION OF A TUNABLE LASER

A cable television transmitter includes a substrate including a silicon material, control electronics disposed in the substrate, and a gain medium coupled to the substrate. The gain medium includes a compound semiconductor material. The cable television transmitter also includes an optical modulator optically coupled to the gain medium and electrically coupled to the control electronics, a waveguide disposed in the substrate and optically coupled to the gain medium, a first wavelength selective element characterized by a first reflectance spectrum and disposed in the substrate, and a second wavelength selective element characterized by a second reflectance spectrum and disposed in the substrate. The cable television transmitter further includes an optical coupler disposed in the substrate and joining the first wavelength selective element, the second wavelength selective element, and the waveguide and an output mirror. 1. (canceled)2. A tunable laser comprising:a gain medium comprising a compound semiconductor material; anda substrate comprising a silicon material, defining a waveguide, and supporting the gain medium;a first tunable wavelength selective element disposed in the substrate and characterized by a first reflectance spectrum having a first plurality of reflectance peaks separated by a first spacing interval; anda second tunable wavelength selective element disposed in the substrate and characterized by a second reflectance spectrum having a second plurality of reflectance peaks separated by a second spacing interval that is different from the first spacing interval.3. The tunable laser of claim 2 , wherein a surface of the compound semiconductor material forms an output mirror claim 2 , and wherein the first and second tunable wavelength selective elements are optically coupled with the gain medium through the waveguide claim 2 , such that the first and second reflectance spectra constructively interfere at a single one of each of the first and second ...

VCSEL Narrow Divergence Proximity Sensor

A proximity sensor which uses very narrow divergent beams from Vertical Cavity Surface Emitting Laser (VCSEL) for the illumination source is disclosed. Narrow divergent beams in the range 0.5 to 10 degrees can be achieved to provide high proximity sensing accuracy in a small footprint assembly. One approach to reducing the beam divergence is to increase the length of the VCSEL resonant cavity using external third mirror. A second embodiment extends the length of the VCSEL cavity by modifying the DBR mirrors and the gain region. Optical microlenses can be coupled with the VCSEL to collimate the output beam and reduce the beam divergence. These can be separate optical elements or integrated with the VCEL by modifying the substrate output surface profile or an added a transparent layer. These methods of beam divergence reduction are incorporated into various embodiment configurations to produce a miniature proximity sensor suitable for cell phones and tablets. 1. An optical sensor module comprising:an optical source including a VCSEL device operable to generate a narrow divergence source beam directed through a window toward an object, the narrow divergence source beam having a full-width half-maximum beam divergence of no more than 10 degrees;an optical detector to sense light reflected back from the object illuminated by the narrow divergence source beam; anda computation device operable to determine a distance to the object or a physical characteristic of the object based at least in part on a signal from the optical detector.2. The optical sensor module of wherein the optical detector is disposed such that light specularly reflected from the window is not incident on the optical detector.3. The optical sensor module of further including a baffle disposed between the VCSEL devices and the optical detector.4. The optical sensor module of wherein the VCSEL device includes a gain section having multiple gain sections separated from each other by respective tunnel ...