Твердотельный лазер

Полезная модель относится к лазерной технике. Твердотельный лазер содержит корпус, активный элемент, лампу накачки и резонатор, состоящий из оптически связанных устройства для излома оси резонатора в оправе и концевого элемента в оправе, включающего выходное и глухое зеркала. Устройство для излома оси резонатора выполнено в виде трехгранной призмы БкР - 180°, концевой элемент выполнен в виде стеклянной подложки с нанесенными выходным и глухим зеркалами. Резонатор содержит электрооптический затвор и поляризатор, а оправа с концевым элементом и оправа с устройством для излома оси имеют плоскую опорную поверхность, опирающуюся на соответствующую торцевую грань корпуса. Корпус имеет две противоположные плоские боковые грани, параллельные оптической оси резонатора, причем в корпусе выполнена сквозная полость прямоугольной формы, проходящая через указанные противоположные плоские боковые грани. На боковых гранях корпуса напротив полости установлены две платформы, на первой платформе закреплен первый отражатель, а на второй платформе закреплен второй отражатель, лампа накачки, лазерный электрооптический затвор и поляризатор. Платформы установлены так, что закрепленные на них элементы обращены внутрь сквозной полости, при этом первый и второй отражатели, имеющие внутреннюю рабочую поверхность в виде части цилиндра с диффузно отражающим покрытием, совместно образуют цилиндрическую поверхность, охватывающую активный элемент и лампу накачки, при этом поляризатор и лазерный электрооптический затвор расположены между глухим зеркалом и трехгранной призмой БкР - 180°. Заявляемая полезная модель обеспечивает стабилизацию энергетических и пространственных параметров излучения в широком диапазоне температур окружающей среды и при воздействии ударов и вибрации в широком диапазоне частот и ускорений. 4 ил. РОССИЙСКАЯ ФЕДЕРАЦИЯ (19) RU (11) (13) 170 707 U1 (51) МПК H01S 3/02 (2006.01) H01S 3/115 (2006.01) ФЕДЕРАЛЬНАЯ СЛУЖБА ПО ИНТЕЛЛЕКТУАЛЬНОЙ СОБСТВЕННОСТИ (12) ФОРМУЛА ПОЛЕЗНОЙ МОДЕЛИ ...

Modular aufgebauter, gepulster Mehrwellenlängen-Festkörperlaser für medizinische Therapieverfahren

LASERPUMPKAVITAET HOHER REFLEKTANZ.

Pockelszellentreiberschaltung und Verfahren zum Betrieb einer Pockelszelle

Eine Pockelszellentreiberschaltung (1) mit einem ersten Schaltungsknoten (41), der mit einem ersten Anschluss einer Pockelszelle (30) verbindbar ist, und einem zweiten Schaltungsknoten (42), der mit einem zweiten Anschluss einer Pockelszelle (30) verbindbar ist, wobei der erste Schaltungsknoten (41) über einen ersten Schalter (11) mit einem positiven Potential (21) verbunden ist und ein zweiter Schalter (12) an den zweiten Schaltungsknoten (42) angeschlossen ist, ist dadurch gekennzeichnet, dass der zweite Schaltungsknoten (42) über den zweiten Schalter (12) mit einem negativen Potential (22) verbunden ist und der erste mit dem zweiten Schaltungsknoten (41, 42) über einen zur Entladung einer angeschlossenen Pockelszelle (30) angesteuerten Kurzschlussschalter (13) verbunden ist.

Quality-switched amplifier arrangement, has pockel-cell, delay plate and polarizing component for quality circuit and uncoupling is obtained by polarizing component, which is made from double refracting crystal

The arrangement has a pockel-cell (21), a delay plate (22) and a polarizing component (31) for a quality circuit and uncoupling is obtained by a polarizing component. The polarizing component is a thin section polarizer made from a double refracting crystal and also a beam displacer. The necessary high voltage is adjusted by the phase lag value of the delay plate. The desired uncoupling degree or resonator quality is varied over the phase lag value of the delay plate and also adjusted over the high voltage value.

Verwendung eines Scheibenlasers zur Kristallisation von Siliziumschichten

Optischer Molekularverstaerker

METHOD AND APPARATUS FOR PRODUCING ISOLATED LASER PULSES HAVING A FAST RISE TIME

... 1423321 Lasers UNITED STATES ATOMIC ENERGY COMMISSION 22 Jan 1974 [9 Feb 1973] 2999/74 Heading H1C To terminate prematurely a giant pulse from an optically pumped Q-switched laser, a secondary laser output directed by mirrors 28, 30 triggers a spark gap 38 to de-energise an electro-optical modulator (EOM) 24, the consequential change of polarisation conditions within the laser resonator enabling the main laser output to be obtained by way of a polarising element 22. In both arrangements the resonator includes two polarisers 20, 22, which are crossed to suppress stimulated emission build-up in Fig. 1 and are arranged in Fig. 5 such that multiple reflections between mirrors 14, 42 can normally occur. The cycle of operations is started by energising the EOM. As applied to the Q- switched laser, Fig. 1, the secondary output becomes effective to trigger the spark gap only when the EOM cell voltage effectively uncrosses the polarisers and causes a giant pulse to be emitted. In the case of the ...

Method and device for producing high-power light pulses of short duration

... 1,166,922. Lasers. COMMISSARIAT A L'ENERGIE ATOMIQUE. 13 March, 1967 [25 March, 1966], No. 11709/67. Heading H1C. Coherent light generated in a laser resonant cavity is concentrated into a wave packet having a length which is less than the length of the cavity and is then extracted from the cavity. The active medium 9 is initially pumped while cavity reflector 2 is non-parallel to reflector 13. With the reflectors parallel, electro-optical modulator M, consisting of a Pockels cell 12 and a Glan prism 10, is energized with A.C. so that its instant of maximum transmission recurs with a period equal to the time taken for light to travel from the modulator to reflector 2 and back to the modulator. As a result photons emitted from the active medium tend to concentrate in a wave packet which is transmitted by the modulator at the instant of maximum transmission. When this wave packet has formed a D.C. voltage is applied to electrooptical switch C, also consisting of a Pockels cell and Glan prism ...

PULSED LASERS SYSTEMS

... 1333892 Lasers SIEMENS AG 7 Jan 1972 [5 Feb 1971] 770/72 Heading H1C In a Q-switched laser, a photo-diode 5 detects the onset of laser emission by monitoring the radiation reflected from a Brewster angle surface of an electro-optic crystal 2 mounted in the laser resonator 3, 4, the photo-diode output being applied through a matching network 6 to a high voltage generator 7 which switches the crystal 2 into an optically transmissive state. The laser comprises a YAG bar 1 and a LiNO 3 electro-optic crystal 2, surfaces of the bar and crystal being inclined at the Brewster angle to the optical axis to polarize the laser beam and to avoid the formation of Fabry Perot resonators. The mirror 4 may be formed by a dielectric layer on the squared-off end of the crystal 2. The laser may be pumped by a flash lamp and its primary emission may be either pulsating or continuous.

Ion source by matrix-assisted laser desorption/ionization

Semiconductor lasers

SELFACTIVATING A FREQUENCY SOLID RING LASER, LASER SHOCK IRRADIATION PROCEDURE AND THIS USING SYSTEM

LASERVORRICHTUNG

Q-switched solid-state laser

Bei einem gütegeschalteten Festkörperlaser mit einem Resonator (3, 30) in Form eines linearen Resonators oder Ringresonators, der ein aktives Lasermaterial (1) und zumindest einen ersten und einen zweiten Spiegel (4, 5) aufweist und der eine Resonatorlänge (a) im Fall der Ausbildung als linearer Resonator von weniger als 50 mm, vorzugsweise weniger als 25 mm, und im Fall der Ausbildung als Ringresonator von weniger als 100 mm, vorzugsweise weniger als 50 mm aufweist schwingt im Resonator (3) zumindest im Wesentlichen nur ein einziger longitudinaler Mode an. Der Resonator (3, 30) ist als instabiler Resonator ausgebildet, wobei einer der Spiegel (4, 5) ein Gradientenspiegel ist.

DENTALLASERANORDNUNG

A dental laser arrangement switchable between different modes of operation, the arrangement including a laser device operable as a laser oscillator and as a laser amplifier. The laser device includes a laser resonator having a pump unit and an active modelocker as well as an optic loss element that introduces selective losses in the resonator. The laser arrangement further includes a laser beam-out-coupling unit. The modelocker is connected to a control circuit for switching between a CW-mode of operation for coagulating soft tissue, in which the modelocker is switched off, and two short-pulse modes of operation in which high frequency signals of equal frequencies, but different powers are applied by the control circuit to the modelocker so as to generate laser pulses of a pre-determined duration. One of the two short-pulse modes of operation is provided for ablation of hard tooth tissue, and the other short-pulse mode of operation, in which the laser radiation has a lower peak power in ...

Pumpeinrichtung zum Pumpen eines verstärkenden Lasermediums

The invention relates to a pump device for pumping an amplifying laser medium (1), comprising a radiation source (13) with a plurality of laser diodes (15, 16) that emit laser beams (17) which have parallel beam axes (a) running in the direction of a z axis and which diverge at least twice as much in the direction of an x axis perpendicular to the z axis as in the direction of a y axis perpendicular to the z axis and to the x axis. The pump device also comprises at least one optical component (22, 22', 22") with at least one cylinder surface (23), with which at least some of the laser beams (17) emitted by the laser diodes (15, 16) interact. The cylinder surface (23) lies parallel to the x axis and is curved on a plane perpendicular to the x axis.

Gütegeschalteter Festkörperlaser

A Q-switched solid-state laser having a peak power of more than 1 MW comprises a resonator, which has a first and a second end mirror (6, 7) and optical elements which interact with the laser beam between the first and the second end mirrors (6, 7) and which comprise a pumped laser medium (1), wherein the laser beam is reflected from the first end mirror (6) in a direction which is at least substantially parallel to and equidirectional with the direction in which the laser beam is reflected from the second end mirror (7). The optical elements which interact with the laser beam between the first and the second end mirrors (6, 7) are designed in such a way that, upon propagation of an image (F) proceeding from the first end mirror (6), they have the effect that the image (F), after propagation via the optical elements lying between the first and the second end mirrors (6, 7) and reflection at the second end mirror (7), as viewed in the direction of propagation, is rotated about the beam axis ...

Gütegeschalteter Festkörperlaser

A Q-switched solid-state laser having a peak power of more than 1 MW comprises a resonator, which has a first and a second end mirror (6, 7) and optical elements which interact with the laser beam between the first and the second end mirrors (6, 7) and which comprise a pumped laser medium (1), wherein the laser beam is reflected from the first end mirror (6) in a direction which is at least substantially parallel to and equidirectional with the direction in which the laser beam is reflected from the second end mirror (7). The optical elements which interact with the laser beam between the first and the second end mirrors (6, 7) are designed in such a way that, upon propagation of an image (F) proceeding from the first end mirror (6), they have the effect that the image (F), after propagation via the optical elements lying between the first and the second end mirrors (6, 7) and reflection at the second end mirror (7), as viewed in the direction of propagation, is rotated about the beam axis ...

ELECTROOPTICAL QUALITY SWITCH WITH SINGLE CRYSTAL OF THE TYPE LANGASIT

Laser device

DIODE PUMPED SLAB LASER

This invention relates to a diode pumped slab laser in the form of a slab (1 ) where two opposite faces (2, 3) are adapted to receive pumping radiation with the faces being cut at the Brewsters angle at one sad (6, 7) to provide entrance/exit faces for the lasing radiation. The laser radiation beam follows a zig-zag path in the slab (1) and is contained within the slab by total internal resection. The laser slab (1) is contained within an optical cavity which results in the laser beam completing a double zig-zag beam path. The design results in good pump/mode matching, mitigates thermally induced birefringence problems, overcomes amplified spontaneous emission problems, requires no coatings or curved surfaces, and is easy and relatively inexpensive to make. The slab (1) can be used within both Quasi-CW and CW modes.

Laser

Dispositif de contrôle de l'émission laser d'un cristal

Anordnung zur Aussendung modulierter, nach dem Laserprinzip erzeugter Strahlung

Laser allo stato solido

Verfahren zum Bohren von Uhrensteinen mittels Laserstrahlen und Anordnung zur Durchführung des Verfahrens

Laser-Oszillator mit Auskopplungsmodulator

VERFAHREN ZUM EINSTELLEN DER LEISTUNG VON LASER-RIESENIMPULSEN.

Procédé et dispositif de production d'impulsions lumineuses brèves de grande puissance

Einrichtung mit einem Laser

Dispositif destiné à envoyer dans l'oeil une radiation monochromatique dans un but thérapeutique

Functional composite electro-optic Q switch

Laser annealing device and laser annealing method

The present invention is a laser annealing device which anneals an amorphous silicon film (5) by irradiating the amorphous silicon film (5) with laser light. The laser annealing device comprises: a first pulse laser (6) for generating first laser light (L1) with a prescribed pulse width and a prescribed wavelength; a second pulse laser (7) for generating second laser light (L2) with a pulse width and a wavelength that are longer than those of said first laser light (L1); a synthesizing means (8) for synthesizing said first laser light (L1) and said second laser light (L2) into light having the same optical axis; and a control means (3) for controlling the timing for the emission of the first and second laser light (L1, L2) by operating said first and second pulse lasers (6, 7). The control means (3) controls said first pulse laser (6) such that said first laser light (L1) is emitted at a prescribed timing within the pulse width of said second laser light (L2).

SOLID-STATE LASER DEVICE, SOLID-STATE LASER SYSTEM, AND LASER DEVICE FOR LIGHT EXPOSURE DEVICE

The elimination of the mass spectrometer used for LDI pulse laser pulses in the

LASER EQUIPMENT

High power pulsed laser generator - has facial plane of electro=optical cell at 90 degrees to axis of crystal

optical Stroboscope-oscilloscope of sampling

LASER OSCILLATOR PULSATES HAS VARIABLE DURATION Of IMPULSE

La présente invention concerne le domaine des oscillateurs laser pulsés. Elle se rapporte à un oscillateur laser pulsé (15) comprenant une cavité laser (15), ladite cavité laser (15) comprenant un milieu laser (4) apte à être pompé par un rayonnement de pompe émis par au moins une source de rayonnement de pompe (5) et à émettre un rayonnement laser, ladite cavité laser (15) comprenant des moyens d'obturation (7) aptes à obturer ladite cavité pendant une durée d'obturation, dans lequel lesdits moyens d'obturation sont des moyens d'obturation électro-optiques, dans lequel lesdits moyens d'obturation sont aptes à être alimentés par une tension d'alimentation variable.

MICROLASER SOILDE, HAS OPTICAL PUMPING BY SEMICONDUCTOR LASER HAS SURGES VERTICAL

PROCESS AND DEVICE FOR the REMOVAL OF MATTERS USING LASER BEAMS

MONOLITHIC SOLID MICROLASER HAS ACTIVE RELEASE BY WEAK TENSION OF ORDER

Microlaser comportant un milieu constitué d'un matériau actif laser, formant une première cavité résonnante entre un miroir d'entrée et un miroir intermédiaire, un second matériau formant une seconde cavité résonnante entre le miroir intermédiaire et un miroir de sortie, caractérisé en ce que des moyens de réduction du faisceau laser sont disposés en entrée de la première cavité résonante, l'ensemble des deux cavités et des moyens de réduction du faisceau laser étant monolithiques ...

PROCESS Of ASSEMBLY OF TWO STRUCTURES AND DEVICE OBTAINED BY the PROCESS. APPLICATIONS TO THE MICROLASERS

LASER AT THE SOLID STATE HAS OPTICAL PUMPING

Improvements with the systems releases for lasers

VELOCIMETER AND METHOD OF MANUFACTURING ARTICLE

Short pulse laser system

OPTICAL MODULATOR AND METHOD OF PROVIDING THE SAME

An optical modulator comprises a Q-switch comprising a first pyroelectric crystal having opposing end faces disposed along a first pyroelectric axis, and a charge dissipating device comprising a second pyroelectric crystal having opposing end faces disposed along a second pyroelectric axis. The charge dissipating device is configured to provide pyroelectric charge from the opposing end faces of the second pyroelectric crystal to neutralize pyroelectric charge on opposing end faces of the first pyroelectric crystal.

QUALITY-SWITCHED LASER WITH SEED AND ACTIVE FREQUENCY STABILIZATION

The invention relates to a method for frequency stabilization of quality-switched lasers, with the resonator length being varied over at least half the wavelength of the laser and pulse resolution being set as a function of this measurement; the resonator length is varied (11) over at least two half wavelengths of the laser, and the pulse resolution is set with or after the time of occurrence of a further resonance, referred to as the initiation resonance, corresponding to the resonance condition. The laser (1) includes a seed laser (7), an isolator (8) and a mirror (2) containing a resonator, a quality switch (3) and a device for setting the initiation time (17) of the quality switch (3).

PULSE LASER OSCILLATOR AND METHOD FOR CONTROLLING PULSE LASER OSCILLATION

This pulse laser oscillator is provided with: a first electro-optical element that polarizes light corresponding to an applied voltage; and a voltage control apparatus, which applies a voltage to the first electro-optical element, and controls the voltage. The value of a voltage to be applied to the first electro-optical element is changed with time by means of the voltage control apparatus, and the pulse width of a laser beam is controlled.

PULSED LASER

A Q-switched pulsed laser in which the Q-factor of the laser cavity is switched between a low value enabling storage of supplied energy in the cavity and a high value enabling a pulse emission of the stored energy. The cavity is filled with a mixture of iodide vapour and a buffer gas, the buffer gas being selected to minimise quenching of the excited state of the iodide vapour. The partial pressures of the iodide vapour and the buffer gas are selected to maintain the single pass small signal gain of the laser smaller than the extinction of the switching means.

OPTICAL DEVICE

An optical device of this invention is such that complicated adjustment of the arrangement is not needed unlike a conventional optical device for outputting light having a frequency different from that of the input light by means of a nonlinear optical crystal. Electrodes (12A and 12B) for Q-switching, electrodes (9A and 9B) for phase adjustment and a periodical domain inversion portion (15) are disposed at predetermined positions in path (2) inside an optical crystal body (1) having nonlinear optical properties, electro-optical properties and laser activity. Oscillation light (P1) is produced by inputting light (P0) given from the input side (3), and output light (P2) having a frequency different from the frequency of the input light (P0) is outputted from the output side (4) by the nonlinear optical property and by the generation of harmonic or by optical parametric oscillation by use of the periodical domain inversion portion (15). The refractive index of the part of nonlinear crystal ...

Operating a Pockels Cell

A Pockels cell driver circuit has a first circuit node that can be connected to a first terminal of a Pockels cell and a second circuit node that can be connected to a second terminal of the Pockels cell. The first circuit node is connected via a first switch to a positive potential and the second circuit node is connected via a second switch to a negative potential. The first circuit node is connected to the second circuit node via a short-circuit switch which is controlled for discharge of a linked Pockels cell. 1. A driver circuit for a Pockels cell , the driver circuit comprising:a first circuit node configured to be connected to a first terminal of the Pockels cell, the first circuit node being connected via a first switch to a positive potential; anda second circuit node configured to be connected to a second terminal of the Pockels cell, the second circuit node being connected via a second switch to a negative potential,wherein the first circuit node is connected to the second circuit node via a short-circuit switch configured to be activated for discharge of the Pockels cell,wherein the first, second, and short-circuit switches each comprise a respective serial connection of one or more individual switches, and each of the individual switches comprises at least one of a turn-on driver circuit or a turn-off driver circuit, and the turn-on driver circuits of the first and second switches and the turn-off driver circuits of the short-circuit switch connected in a first serial connection at respective input terminals of the turn-on driver circuits of the first and second switches and the turn-off driver circuits of the short-circuit switch, or', 'the turn-off driver circuits of the first and second switches and the turn-on driver circuits of the short-circuit switch connected in a second serial connection at respective input terminals of the turn-off driver circuits of the first and second switches and the turn-on driver circuits of the short-circuit switch., ' ...

Solid-state laser device, solid-state laser system, and laser device for exposure device

A solid state laser device includes a seed laser that outputs continuous wave laser seed light, a light intensity changeable unit that changes a light intensity thereof and outputs seed pulse light, a CW excitation laser that outputs continuous wave excitation light, an amplifier that amplifies the seed pulse light and outputs amplified light based on an amplification gain increased by the excitation light, a wavelength conversion unit that converts a wavelength of the amplified light and outputs harmonic light, and a light intensity control unit that allows the light intensity changeable unit to output the seed pulse light after a certain time elapsed from an input of an external trigger signal each time the signal is input and output suppression light that suppresses an increase of the amplification gain in a period after an output of the seed pulse light until an input of a next external trigger signal.

Pulse transmission or reflection mode laser

A Q-switched laser in which the laser cavity contains on one side of the laser rod (1) a mirror (2) and on the other side of the laser rod (1) in sequence a polarizer (4) and an electro-optical cell (5) and first fold-back reflector means (3) to fold-back the beam to a second reflector (6) arranged to direct the beam back to the polarizer (4) to form a loop around the electro-optical cell (5). The mirror (2) is a partial reflector to allow output from the laser rod (1) through the mirror in pulse reflection mode or is a total reflector to allow output from the polarizer (4) in pulse transmission mode.

POLARIZATION INDEPENDENT LIGHT MODULATION MEANS USING BIREFRINGENT CRYSTALS

A first optically birefringent crystal divides an incident randomly polarized light beam into two linearly polarized orthogonal components, namely, an ordinary ray and an extraordinary ray. The incident light beam is so related to the optic axis of the birefringent crystal that ordinary ray is undeviated but the exgraordinary ray is deviated by a selected amount, both of the rays emerging from the birefringent crystal parallel to each other. The amount of deviation is a function of the index of refraction and the length of the path through the crystal. The spaced rays are then directed through an electro-optical polarization modulator which electronically converts the linearly polarized components to elliptically polarized beams with the eccentricity dependent upon the magnitude of an applied electric field. For a particular magnitude of applied electric field, the polarization modulator will cause a 90 DEG rotation of the orthogonal components. The two emerging rays are then passed through ...

Laser

PCT No. PCT/GB94/00554 Sec. 371 Date Dec. 1, 1995 Sec. 102(e) Date Dec. 1, 1995 PCT Filed Mar. 18, 1994 PCT Pub. No. WO94/22189 PCT Pub. Date Sep. 29, 1994A pulsed laser comprises a laser rod (6), and is pumped by diode array (3) selected such that with additional components (7, 9) only a maximum of two longitudinal modes are generated between mirror (1) and output coupler (2). By slow Q-switching Q-switch (9) hoped to get a single longitudinal mode output pulse. However if on the onset of the relaxation pulse mode beating is detected by detector (28), indicating that two longitudinal modes are present, then the optical path length of the resonator is changed by quarter of one wave length, by applying an electrical signal to a pulse length control means (10), such that one of the modes is suppressed prior to the Q-switch being fully opened. The output may be amplified by amplifier arrangement (24).

Picosecond laser apparatus and methods for its operation and use

Apparatuses and methods are disclosed for applying laser energy having desired pulse characteristics, including a sufficiently short duration and/or a sufficiently high energy for the photomechanical treatment of skin pigmentations and pigmented lesions, both naturally-occurring (e.g., birthmarks), as well as artificial (e.g., tattoos). The laser energy may be generated with an apparatus having a resonator with the capability of switching between a modelocked pulse operating mode and an amplification operating mode. The operating modes are carried out through the application of a time-dependent bias voltage, having waveforms as described herein, to an electro-optical device (e.g., a Pockels cell) positioned along the optical axis of the resonator.

Electrooptic Q-switch element made of crystal

This invention is a kind of electrooptic Q-switch element made of a single crystal and belongs to the application of crystal in electrooptic technology field. The invention consists of electrooptic Q-switch which is made of La₃Ga₅SiO₁₄ or Nd:La₃Ga₅SiO₁₄ or the other related crystal materials such as La₃Ga_5-xAl_xSiO₁₄, Sr₃Ga₂Ge₄SiO₁₄, Na₂CaGe₆O₁₄, Ca₃Ga₂Ge₄O₁₄, La₃Ga_5.5Nb_0.5O₁₄ and La₃Ga_5.5Ta_0.5O₁₄ with the common shape or a specific shape containing Brewster angle as shown in figure. This kind of electrooptic Q-switch can be used in YAG laser and other laser. It overcomes the shortages of the commercial Q-switches, such as the high, un-adjustable, low stable half-wave voltage ...

Q-SWITCHED LASER WITH STABILIZED OUTPUT ENERGY

The present disclosure relates a laser arrangement () and a method of the laser arrangement, arranged to output energy in the form of laser emission, for emitting controlled Q-switched laser emission. The laser arrangement comprises a gain medium () arranged to be excited when pumped, an optical resonator (), an active Q-switch () arranged in the optical resonator, said active Q-switch () being controllable between at least a high loss state and a low loss state, and being arranged to introduce loss in the optical resonator to prevent lasing in the high loss state and to affect lasing minimally in the low loss state, a photo detector () arranged to detect the presence of a free running pulse (′) generated by the optical resonator and which occurs when a lasing threshold is reached and a processing circuitry () arranged to control (S) of the state of the active Q-switch based on the detection of the free running pulse. 116-. (canceled)171. A laser arrangement () , arranged to output energy in the form of laser emission , for emitting controlled Q-switched laser emission , the arrangement comprising:{'b': '2', 'a gain medium () arranged to be excited when pumped;'}{'b': '3', 'an optical resonator ();'}{'b': 4', '4, 'an active Q-switch () arranged in the optical resonator, said active Q-switch () being controllable between at least a high loss state and a low loss state, and being configured to introduce loss in the optical resonator to prevent lasing in the high loss state and to affect lasing minimally in the low loss state;'}{'b': 5', '1, 'a photodetector () configured to detect the presence of a free running pulse (′) generated by the optical resonator and which occurs when a lasing threshold is reached; and'}{'b': 6', '4, 'a processing circuitry () configured to control (S) of the state of the active Q-switch based on the detection of the free running pulse.'}184. The laser arrangement according to claim 17 , wherein the active Q-switch () is either an acousto- ...

Q-SWITCHED OSCILLATOR SEED-SOURCE FOR MOPA LASER ILLUMINATOR APPARATUS AND METHOD

An apparatus, method and system that uses a Q-switched laser or a Q-seed source for a seed pulse signal having a controlled high-dynamic-range amplitude that avoids and/or compensates for pulse steepening in high-gain optical-fiber and/or optical-rod amplification of optical pulses. Optionally, the optical output is used for LIDAR or illumination purposes (e.g., for image acquisition). In some embodiments, well-controlled pulse shapes are obtained having a wide dynamic range, long duration, and not-too-narrow linewidth. In some embodiments, upon the opening of a Q-switch in an optical cavity having a gain medium, the amplification builds relatively slowly, wherein each round trip through the gain medium increases the amplitude of the optical pulse. Other embodiments use quasi-Q-switch devices or a plurality of amplitude modulators to obtain Q-seed pulses. These configurations provide optical pulses having wide dynamic ranges that ameliorate problems of pulse steepening, non-linear spectral broadening and the like in very-high-power MOPA devices. 120.-. (canceled)21. An apparatus comprising: a first optical pump source,', 'a first optical-gain waveguide optically coupled to receive pump light from the first optical pump source and configured to amplify signal light that propagates through the first optical-gain waveguide, and', 'a solid-state optical amplifier configured to receive the amplified signal light from the first optical-gain waveguide and, in a first mode, configured to attenuate the amplified signal light, and in a second mode, configured to enable generation of a Q-switched pulsed-laser seed signal., 'a Q-switched seed laser, wherein the Q-switched seed laser includes22. The apparatus of claim 21 , wherein the first optical-gain waveguide and the solid-state optical amplifier are configured as a Q-switched ring laser claim 21 , the ring laser further comprising an optical isolator configured to force unidirectional light travel around the ring laser.23. ...

PULSE SLICER IN LASER SYSTEMS

An apparatus (such as a laser-based system) and method for providing optical pulses in a broad range of pulse widths and pulse energies uses a pulse slicer which is configured to slice a predefined portion having a desired pulse width of each of the one or more output optical pulses from a laser oscillator, in which timings of a rising edge and a falling edge of each sliced optical pulse relative to a time instance of a maximum of the corresponding each of the one or more output optical pulses from the laser oscillator, are chosen at least to maximize amplification efficiency of the optical amplifier, which may be located after the pulse slicer, and to provide the one or more amplified output optical pulses each having the desired pulse energy and pulse width. 121-. (canceled)22. A system comprising:a laser oscillator having a lasing medium and a back reflection mirror;an output mirror, configured to provide one or more output optical pulses;a pulse forming element between the back reflection mirror and the output mirror, the pulse forming element configured to provide formation of the one or more output optical pulses;a pulse slicer downstream of the laser oscillator and configured to slice a portion having a desired pulse width of each of the one or more output optical pulses;an optical amplifier downstream of the pulse slicer and configured to amplify the sliced portion of each of the one or more output optical pulses to a desired pulse energy to provide one or more amplified output optical pulses;wherein timings of a rising edge and a falling edge of each sliced optical pulse, relative to a time instance of a maximum of the corresponding each of the one or more output optical pulses, is chosen at least to maximize amplification efficiency of the optical amplifier and to provide the one or more amplified output optical pulses each having the desired pulse energy and pulse width;wherein the pulse forming element is a Q-switch component;wherein the Q-switch ...

PICOSECOND LASER APPARATUS AND METHODS FOR ITS OPERATION AND USE

MID-IR MICROCHIP LASER: ZnS:Cr-2+ LASER WITH SATURABLE ABSORBER MATERIAL

A method of fabrication of laser gain material and utilization of such media includes the steps of introducing a transitional metal, preferably Cr2+ thin film of controllable thickness on the ZnS crystal facets after crystal growth by means of pulse laser deposition or plasma sputtering, thermal annealing of the crystals for effective thermal diffusion of the dopant into the crystal volume with a temperature and exposition time providing the highest concentration of the dopant in the volume without degrading laser performance due to scattering and concentration quenching, and formation of a microchip laser either by means of direct deposition of mirrors on flat and parallel polished facets of a thin Cr:ZnS wafer or by relying on the internal reflectance of such facets. The gain material is susceptible to utilization of direct diode or fiber laser pumping of a microchip laser with a level of power density providing formation of positive lens and corresponding cavity stabilization as well ...

Laser assembly

Eine bekannte Laseranordnung weist folgende Merkmale auf: a) die Laseranordnung umfasst mindestens folgende Elemente, die nacheinander entlang der optischen Achse angeordnet sind: • einen Auskoppelspiegel (10), • ein Lasermedium (20), • einen phasenkonjugierenden Spiegel (30, PKS) auf der Basis einer stimulierten Brillouin-Streuung (SBS), • einen Endspiegel (50), b) der Auskoppelspiegel (10) und der Endspiegel (50) bilden einen Startresonator (A), c) der Auskoppelspiegel (10) und der phasenkonjugierende Spiegel (30) bilden einen Hauptresonator (B). Die neue Laseranordnung soll so ausgebildet sein, dass ein Laserpuls variabler und einstellbarer Energie hinsichtlich seines Zeitpunktes mit einer hohen Genauigkeit vorher bestimmbar ist. Hierzu ist zwischen dem phasenkonjugierenden Spiegel (30) und dem Endspiegel (50) ein steuerbarer Modulator (40) angeordnet.

Frequency doubling device using an electrically driven optical index grating

The present invention provides a frequency doubler comprising an optical index grating which can be driven electrically by means of two continuous electrodes, the grating being created by the presence of polarisation domains (+P) which are periodically separated by polarisation domains (-P), the electrodes making it possible to compensate for the index variations between the domains (+P) and the domains (-P) electrooptically. ...

Импульсный твердотельный лазер

Полезная модель относится к лазерной технике. Импульсный твердотельный лазер содержит в резонаторе глухое зеркало, две 90-градусные призмы-крыши, активный и электрооптический элементы, поляризатор. Первая призма-крыша расположена по одну сторону от активного элемента таким образом, что ее ребро при вершине перпендикулярно геометрической оси активного элемента и лежит в вертикальной плоскости, проходящей через эту ось. Вторая призма-крыша расположена по другую сторону от активного элемента таким образом, что ее ребро при вершине перпендикулярно геометрической оси активного элемента и лежит в горизонтальной плоскости, проходящей через эту ось. Нерабочая торцевая грань второй призмы-крыши лежит в вертикальной плоскости, проходящей через геометрическую ось активного элемента. Между активным элементом и поляризатором дополнительно установлена четвертьволновая пластина. Зеркало, рядом с которым расположены электрооптический элемент и поляризатор, находится по ту же сторону от активного элемента ...

Giant pulse laser with narrow bandwidth emission line - has main resonator bounded by two reflectors, containing system components

The auxiliary resonator is bounded by the two reflectors of the main resonator and by third reflector located outside the main resonator. The polariser is so arranged in the main resonator, w.r.t. the polarisation rotator and the laser medium, that radiation in a first polarisation direction is passed without substantial influence. The radiation in the second polarisation direction is reflected out from the main resonator and to the third reflector over an auxiliary radiation path, containing a restrictor of the optical bandwidth of the auxiliary radiation. From the third reflector the radiation is projected back to the polariser, deflecting it to one reflector of the main resonator.

LASER

LASER UNTER VERWENDUNG EINES INSTABILEN HOHLRAUMRESONATORS MIT NEGATIVEM ZWEIG.

Chemically reduced lithium compound-based q-switch

A method 100 suitable for manufacturing Q-switches includes coating 120 a first Z-surface and second Z-surface of an oriented slab of a chemically reducible electro-optic lithium compound crystal (LC slab) with a condensed material including an active chemical operable once activated to chemically reduce the LC; the LC slab with condensed material thereon is heated 130 in a non-oxidizing atmosphere at a temperature above an activating temperature of the condensed material; the LC slab is cooled 140 to a temperature below a quenching temperature below which re-oxidization of the LC slab is inhibited; a finishing process is performed 150 including cutting the LC slab into a plurality of Q-switch devices each having a chemically reduced LC substrate, and forming metal electrodes on opposing sides of the LC substrates that are orthogonal to the Z-surfaces, and coating the Z-surfaces with an antireflective (AR) coating material. The reduction process increases the electrical conductivity of ...

Laser resonator architecture

The invention relates to a laser resonator 5 comprises at least one output coupler 10 a; at least one end reflector 10b; a retroreflector 15; a telescope 20; a gain medium 25 and the telescope 20 is a common telescope 20 provided in a beam path between the retroreflector 15 and both the end reflector 10b and the output coupler 10a. The end reflector 10b may comprise an end mirror or Porro prism. The retro reflector may be a corner cube. Resonator telescope geometry may be optimised for low boresight sensitivity to telescope focus. The arrangement may also be end pumped via a polariser beam splitter which is operable as a Q-switch (Figure 2).

OPTICAL MODULATORS

PULSED LASER

Improvements in or relating to lasers or masers

... 1,068,052. Modulating laser and maser radiation. SIEMENS A.G. April 13, 1964 [April 11, 1963; April 16, 1963; May 22, 1963], No. 15099/64. Heading H1C. The oscillatory radiation path in a laser or maser extends through a modulator which is controllable so that variable proportions of the laser or maser radiation may be retained in the radiation path and picked off from the path. In Fig. 1, laser element 1 lies in a resonant cavity 2, 21, partial reflector 2 forming with a partial reflector 4 a further cavity containing a control element 5, the refractive index is varied by means of a modulating electric field. The assembly 2, 4, 5 forms a variable reflectivity interference mirror allowing the proportions of radiation picked off and retained to be varied. The assembly is adjusted so that a mean beam intensity is picked off in the absence of a modulating field, or element 5 is D.C. biased. In a push-pull system (Fig. 3, not shown) a similar interference mirror is arranged at the ...

Solid laser oscillator

LIGHT BEAM POLARIZATION MODULATOR

... 1368598 Modulating light WESTINGHOUSE ELECTRIC CORP 12 July 1971 [17 Aug 1970] 9139/74 Divided out of 1363885 Heading H4F [Also in Division H1] In the parent Specification 1,363,885 a birefringent crystal 2 divides an incident plane, circularly or elliptically polarized beam 1 into parallel E and O rays 8, 7, which are passed through respective birefringent crystals 11, 10, a #/2 plate 9 and are recombined by a birefringent crystal 3 complementary to crystal 2. Plate 9 serves to render the two path lengths equal so that the recombined beam 11 normally has the same polarization as beam 1. When an electric field is applied along the Z axis of at least one of the crystals 10, 11 (i.e. orthogonal to the optical path and at 0 or 90 degrees to the incident polarization vector) the optical path lengths become unequal due to the changes in refractive index and the polarization of beam 11 is altered. As particularly described in the parent, a beam 1 plane polarized at 45 degrees ...

SURGICAL SOURCE OF SHORT PULSE LASER WITHIN THE MIDDLE INFRARED RANGE

Festkörperlaser

A solid-state laser has an amplifying laser medium (1) for producing a laser beam (4) and a pump device (13, 14) that has at least one laser diode (16) and that produces a pump radiation (5) that impinges on a first lateral face (6) of the laser medium (1), which lateral face is parallel to a z axis and parallel to a y axis that is at right angles to the z axis. On a second lateral face (23), which is opposite the first lateral face (6), the laser medium (1) is cooled by a heat sink (22). The length of a y-1 /e2 region (33) of the pump radiation (5) is shorter than the length of the first lateral face (6) of the laser medium (1) in the direction of the y axis, wherein the y-1/e2 region (33) of the pump radiation (5) denotes a section of the y axis over which the intensity of the pump radiation (5) on the first lateral face (6) of the laser medium (1) has a value that is more than the maximum intensity of the pump radiation (5) on the first lateral face (6) of the laser medium (1) divided ...

DENTALLASERANORDNUNG

PASSIVELY Q-SWITCHED SOLID STATE LASER

Ein passiv gütegeschalteter Festkörperlaser umfasst einen Resonator (1), in dem ein aktives Lasermaterial (2) angeordnet ist und der einen Auskoppel-Endspiegel (6) zur Auskopplung von Laserpulsen aus dem Resonator (1) aufweist, welche eine Pulsdauer von weniger als 1 ns aufweisen, eine optische Faser (13), in welche die aus dem Auskoppel-Endspiegel (6) ausgekoppelten Laserpulse eingekoppelt werden, und ein gechirptes Volumen Bragg-Gitter (17), an welchem eine Reflektion der Laserpulse nach ihrem Durchlauf durch die optische Faser (13) zur Verkürzung der Pulsdauer erfolgt. Die Pulsdauer nach der Reflektion am gechirpten Volumen BraggGitter (17) beträgt weniger als 30 ps. Das im Resonator (1) angeordnete aktive Lasermaterial (2) ist Nd:YAG und im Resonator ist im Weiteren ein von Cr.VAG gebildeter sättigbarer Absorber (3) angeordnet ist, der eine Transmission im ungesättigten Zustand von weniger als 50% aufweist. Die Länge (a) des Resonators (1) liegt im Bereich von 1 mm bis 10mm und die ...

OPTICAL SYSTEM FOR THE SUPPLY OF SHORT LASER IMPULSES

QUALITY-SWITCHED CO2 LASER FOR MATERIAL PROCESSING

DENTALLASERANORDNUNG

LASER DEVICE

LASER AMPLIFIER BUFFER

Q-switched laser

LASER AMPLIFIER BUFFER

SUPPRESSION OF MODE-BEATING NOISE IN A Q-SWITCHED PULSED LASER USING NOVEL Q-SWITCH DEVICE

A novel Q-switch device enables significant quality and value improvement for a Q-switched laser system by achieving a significant reduction of mode-beating noise during the pulsed output. The origin of mode-beating noise in a Q- switched laser is a result of high gain availability and amplification of competing standing-waves in formation, whose optical frequency is a product of natural selection via spatial hole burning in the gain medium. The novel Q- switch device employs an active, electro-optics or acousto-optics, Q-switch in combination with a saturable absorber device, to provide an optimized soft opening of the optical path and a controlled timing of a Q-switched laser. This novel combination offers larger modulation loss than otherwise possible with the active modulator alone, and it allows for higher gain build-up energy extraction efficiency. Specifically, it will enable a low-voltage modulator (< 100 V) for high gain (small-signal gain > 10) and Q-switched operation at high ...

DEEP RED LASER

Incoherent beam combination-based high-energy nanosecond pulse all-fiber laser

Laser device

Disclosed is a laser device. The laser device includes a pulse generator which irradiates a laser beam between a high reflector mirror and an output coupler mirror to amplify and resonate the laser beam, a pulse output section which receives a laser beam pulse amplified and resonated through the output coupler mirror to output the laser beam pulse, and a Q switch which moves backward or forward in a direction perpendicular to a path of the laser beam formed between the pulse generator and the high reflector mirror. The output coupler mirror includes first and second mirrors provided on a base plate. Positions of the first and second mirrors are selectively changed as the Q switch moves backward or forward.

Laser apparatus and photoacoustic apparatus

A laser apparatus that allows selection of a wavelength of output light from a plurality of options. The laser apparatus includes: a resonator made up from an output mirror and reflection means having a plurality of reflective surfaces fixed in position; a laser medium disposed on an optical axis inside the resonator; branch means branching an optical path of a light beam formed on the optical axis when light oscillates in the laser medium into a plurality of optical paths having an end at one reflective surface of the reflection means, the branch means forming a first optical path coinciding with the optical axis when located out of the optical axis, and forming a branch path by moving the light of the optical axis parallel when located on the optical axis.

OBJECT INFORMATION ACQUIRING APPARATUS AND LASER APPARATUS

There is used an object information acquiring apparatus including a laser resonator configured to include two reflection bodies and a Q switch provided between the two reflection bodies and determining a Q value based on a voltage to be applied, an excitation section configured to optically excite a laser medium, a detector configured to detect light output from one of the reflection bodies, a controller configured to control the laser resonator and determine a value of the voltage based on a detection result of the detector and applies the voltage to the Q switch, a receiver configured to receive an acoustic wave propagating from an object based on irradiation of the object with laser light output from one of the reflection bodies, and an acquisition section configured to acquire information on the object based on a reception result of the receiver. 1. An object information acquiring apparatus comprising:a laser resonator configured to include two reflection bodies and a Q switch provided between the two reflection bodies and determining a Q value based on a voltage to be applied;an excitation section configured to optically excite a laser medium;a detector configured to detect light output from one of the reflection bodies;a controller configured to control the laser resonator and determine a value of the voltage based on a detection result of the detector and applies the voltage to the Q switch;a receiver configured to receive an acoustic wave propagating from an object based on irradiation of the object with laser light output from one of the reflection bodies; andan acquisition section configured to acquire information relate to the object based on a reception result of the receiver.2. The object information acquiring apparatus according to claim 1 , further comprising a branch optical element configured to be provided at a stage prior to the detector and guides part of the laser light output from one of the reflection bodies to the detector claim 1 , ...

APPARATUS

Provided is an apparatus for acquiring object information, the apparatus including: first and second laser output unit outputting first and second pulsed laser; a laser controlling unit configured to control each laser output unit; a first or second detecting unit configured to detect an emission timing of laser and output a first or second detection signal; a probe configured to receive an acoustic wave from an object being irradiated with the laser; and a signal processing unit configured to acquire specific information of the object, based on the acoustic wave. The laser controlling unit controls output of at least one of the laser output units so as to decrease a time difference between subsequent first and second pulsed lasers to be output. 1. An apparatus , comprising:a first and a second laser output unit configured to output a first and a second pulsed laser respectively;a laser controlling unit configured to control the first and the second laser output unit;a first detecting unit configured to detect an emission timing of the first pulsed laser and output a first detection signal; anda second detecting unit configured to detect an emission timing of the second pulsed laser and output a second detection signal, whereinthe laser controlling unit controls output of at least one of the first and the second laser output unit, based on a time difference between the first and the second detection signals.2. The apparatus according to claim 1 , whereinthe laser controlling unit controls output of at least one of the first and the second laser output unit so as to decrease a time difference between subsequent first and second pulsed lasers to be irradiated to the object.3. The apparatus according to claim 1 , whereinthe laser controlling unit controls a temperature of a laser medium of the first laser output unit or the second laser output unit.4. The apparatus according to claim 1 , whereinthe laser controlling unit controls the emission timings of the first and ...

LASER SYSTEM

A laser system includes a first laser source with a laser resonator for generating a first pulsed laser beam. The resonator has a back mirror, an outcoupling mirror and an active lasing medium in between. The system includes a second laser source for generating a second pulsed laser beam and an optical block. The optical block includes a coupling polarizer and a first polarization rotator. The optical block is movable back and forth between an active position and a passive position. In its active position the optical block is located between the outcoupling mirror and the active lasing medium such that the coupling polarizer couples the second beam into the laser resonator of the first laser source while the first rotator is positioned between the outcoupling mirror and the coupling polarizer. In the active position of the optical block a second polarization rotator is between it and the back mirror. 1. A laser system comprising:a first laser source having a laser resonator for generating a first pulsed laser beam;said laser resonator having a back mirror, an outcoupling mirror and an active lasing medium disposed between said back mirror and said outcoupling mirror;a second laser source for generating a second pulsed laser beam;a first optical block including a coupling polarizer and a first polarization rotator;said first optical block being movable back and forth between an active position and a passive position;said first optical block, in said active position, being disposed between said outcoupling mirror and said active lasing medium such that said coupling polarizer couples said second pulsed laser beam into said laser resonator of said first laser source while said first polarization rotator is positioned between said outcoupling mirror and said coupling polarizer;said first optical block, in said passive position, being disposed such that said first optical block is not interfering with said laser resonator; and,a second polarization rotator configured to ...

SOLID-STATE LASER DEVICE, SOLID-STATE LASER SYSTEM, AND LASER DEVICE FOR EXPOSURE DEVICE

A solid state laser device includes a seed laser that outputs continuous wave laser seed light, a light intensity changeable unit that changes a light intensity thereof and outputs seed pulse light, a CW excitation laser that outputs continuous wave excitation light, an amplifier that amplifies the seed pulse light and outputs amplified light based on an amplification gain increased by the excitation light, a wavelength conversion unit that converts a wavelength of the amplified light and outputs harmonic light, and a light intensity control unit that allows the light intensity changeable unit to output the seed pulse light after a certain time elapsed from an input of an external trigger signal each time the signal is input and output suppression light that suppresses an increase of the amplification gain in a period after an output of the seed pulse light until an input of a next external trigger signal. 1. A solid state laser device comprising:a seed laser configured to output seed light that is continuous wave laser light;a light intensity changeable unit configured to change a light intensity of the seed light to make the seed light pulsed and output the pulsed seed light as seed pulse light;a CW excitation laser configured to output continuous wave excitation light;an amplifier configured to amplify the seed pulse light and output the amplified seed pulse light as amplified light, based on an amplification gain increased by light excitation by the continuous wave excitation light;a wavelength conversion unit configured to convert a wavelength of the amplified light and output harmonic light; anda light intensity control unit configured to control the light intensity changeable unit according to an input of an external trigger signal, the light intensity control unit allowing the light intensity changeable unit to output the seed pulse light after a certain time elapsed from an input of the external trigger signal each time the external trigger signal is input, ...

High Energy Broadband Laser System, Methods, and Applications

The present invention demonstrates a technique for achieving milli-joule level and higher energy, broad bandwidth laser pulses centered around 2.4 micrometer with a kilohertz and other repetition rate. The key to such technique is to start with a broadband micro-joule level seed laser at around 2.4 micrometer, which could be generated through difference frequency generation, four-wave mixing process and other methods. This micro-joule level seed laser could then be amplified to above one milli-joule through chirped pulse amplification in a Cr2+:ZnSe or Cr2+:ZnS crystal pumped by a commercially available Ho:YAG or other appropriate suitable lasers. Due to the high seed energy, fewer gain passes are needed to achieve a milli-joule level output thus significantly simplifies laser architectures. Furthermore, gain narrowing effect in a typical chirped pulse amplifier is also mitigated and thus enable a broadband output. 1. A method for creating broadband high energy laser pulses centered around 2.4 μm , comprising:a. generating broadband laser seed pulses having a bandwidth of at least 350 nm centered around 2.4 μm and an energy level of at least 10 μJ;b. amplifying the laser seed pulses to an energy greater than one milli-joule; andc. producing laser output pulses having a bandwidth as close as the input and with an energy of at least one milli-joule.2. The method of claim 1 , comprising amplifying the micro-joule level laser seed pulses to an energy of at least one milli-joule by chirped pulse amplification in a Cr:ZnSe or Cr:ZnS crystal.3. The method of claim 2 , comprising pumping the Cr:ZnSe or Cr:ZnS crystal by a pump laser having a spectral output from 1.3 μm to 2.2 μm.4. The method of claim 3 , wherein the pump laser is a Ho:YAG pump laser.5. The method of claim 1 , comprising amplifying the laser seed pulses in a single amplifier stage having a gain equal to or less than 10.6. The method of claim 1 , comprising generating the broadband laser seed pulses by one ...

SINUSOIDAL PHASE MODULATION OF MODE-LOCKED LASERS

An ultrafast mode-locked laser comprising circuitry configured to drive an electro-optic modulator (EOM) in the mode-locked laser with a drive waveform, the drive waveform being a phase-coherent sinusoidal waveform at a frequency equal to a repetition rate of the mode-locked laser, a phase-coherent pulsed waveform at a frequency equal to the repetition rate of the mode-locked laser, or a phase-coherent sinusoidal waveform at a frequency equal to half of the repetition rate of the mode-locked laser. 1. An ultrafast mode-locked laser comprising:a mode-locked laser source configured to output laser pulses having a repetition rate; a half wave plate;', 'a first polarizing beam splitter or polarizer;', 'an electro-optic modulator (EOM);', 'circuitry configured to drive the SEOM with a drive waveform, the drive waveform being a phase-coherent sinusoidal waveform at a frequency equal to half of the repetition rate of the mode-locked laser source; and', 'a second polarizing beam splitter;, 'a synchronous electro-optic modulator (SEOM), comprisingwherein the SEOM is arranged to direct the laser pulses from the laser source through the half wave plate, the first polarizing beam splitter, the EOM, and then to the second polarizing beam splitter;wherein the second polarizing beam splitter is configured to split the light pulses from the EOM into a first pulse train in a first direction having a first polarization state and a second pulse train in a second direction having a second polarization state.2. The ultrafast mode-locked laser of claim 1 , the SEOM is configured to generate a phase modulated output.3. The ultrafast mode-locked laser of claim 1 , the SEOM is configured to generate an amplitude modulated output.4. The ultrafast mode-locked laser of claim 1 , wherein the SEOM comprises a Pockels cell.5. The ultrafast mode-locked laser of claim 1 , further comprising one or more optical elements configured to feed the second pulse train back to the SEOM.6. The ultrafast mode ...

LASER DEVICE AND PHOTOACOUSTIC MEASUREMENT APPARATUS

In a laser device that emits pulsed laser light by emitting excitation light to a laser medium in a state in which a first voltage is applied to a Q switch and changing the voltage applied to the Q switch from a first voltage to a second voltage after the emission of the excitation light, the application start timing of the first voltage during a normal operation is set to a timing at which the intensity of the pulsed laser light periodically changing due to the vibration of the Q switch is maximized. 1. A laser device , comprising:an excitation light source that emits excitation light;a laser medium that receives the excitation light emitted from the excitation light source and emits laser light;a resonator that includes a pair of mirrors with the laser medium interposed therebetween and that emits pulsed laser light by resonating the laser light between the pair of mirrors;a Q switch that is disposed on an optical path of the resonator to change a Q value of the resonator according to an applied voltage and that makes a Q value of the resonator in a case where a first voltage is applied lower than a Q value of the resonator in a case where a second voltage different from the first voltage is applied;a Q switch driving unit that drives the Q switch by applying the first voltage and the second voltage to the Q switch; anda controller that controls the excitation light source and the Q switch driving unit to emit the excitation light to the laser medium in a state in which the first voltage is applied to the Q switch and change a voltage applied to the Q switch from the first voltage to the second voltage after the emission of the excitation light such that the pulsed laser light is emitted,wherein, during a normal operation, the controller applies the first voltage to vibrate the Q switch and applies the second voltage to the Q switch at a timing at which a preset delay time has passed from start of the emission of the excitation light, andan application start ...

LASER DEVICE AND PHOTOACOUSTIC MEASUREMENT APPARATUS

A Q switch is vibrated by applying a first voltage, and pulsed laser light is emitted by applying a second voltage to the Q switch at a point in time at which a preset delay time has passed from the start of emission of excitation light. Then, in this case, a time which is within a period, for which the vibration of the Q switch continues, and at which the intensity of the pulsed laser light periodically changing due to the vibration of the Q switch is maximized in a case where a point in time of application of the second voltage to the Q switch is changed is set as the delay time. 1. A laser device comprising:an excitation light source that emits excitation light;a laser medium that receives the excitation light emitted from the excitation light source and emits laser light;a resonator that includes a pair of mirrors with the laser medium interposed therebetween and that emits pulsed laser light by resonating the laser light between the pair of mirrors;a Q switch that is disposed in an optical path of the resonator to change a Q value of the resonator according to an applied voltage and that makes a Q value of the resonator in a case where a first voltage is applied lower than a Q value of the resonator in a case where a second voltage different from the first voltage is applied;a Q switch driving unit that drives the Q switch by applying the first voltage and the second voltage to the Q switch; anda controller that controls the excitation light source and the Q switch driving unit to emit the excitation light to the laser medium in a case where a voltage applied to the Q switch is the first voltage and change the voltage applied to the Q switch from the first voltage to the second voltage after the emission of the excitation light such that the pulsed laser light is emitted from the resonator,wherein the controller vibrates the Q switch by applying the first voltage, and applies the second voltage to the Q switch at a point in time at which a preset delay time has ...

LASER SYSTEM FOR GENERATING LASER PULSE OF SUB-NANOSECOND DURATION

A laser system for generating a series of laser pulses comprising a laser generator that supplies an injection pulse to an amplifier; said amplifier comprising: a gain medium enclosed between a first mirror and a second, output, mirror opposite to said first mirror; and an optical switch set in the proximity of said first mirror; said laser system being characterized in that said amplifier is an unstable laser resonator and said injection pulse is supplied to said laser resonator in synchronism with opening of said optical switch; said series of laser pulses comprises at least one pulse having a duration shorter than or equal to 2 ns and an energy higher than 100 mJ and at least three times higher than the energy of any other pulse of said series of pulses. 1. A laser system for generating a series of laser pulses comprising a laser generator that supplies an injection pulse to an amplifier; said amplifier comprising: a gain medium enclosed between a first mirror and a second , output , mirror opposite to said first mirror; and an optical switch set in the proximity of said first mirror; said system being characterized in that: said amplifier is an unstable laser resonator , and said injection pulse is supplied to said laser resonator in synchronism with opening of said optical switch; and said series of laser pulses comprises at least one pulse having a duration shorter than or equal to 2 ns and an energy higher than 100 mJ and at least three times higher than the energy of any other pulse of said series of pulses.2. The system according to claim 1 , IS characterized in that said at least one pulse has an energy higher than 500 mJ.3. The system according to claim 1 , characterized in that said at least one pulse has an energy higher than 1 J.4. The system according to claim 1 , characterized in that said series of laser pulses comprises at least one pulse having an energy at least five times higher than the energy of any other pulse of said series of pulses.5. The ...

OPTICAL OSCILLATOR

An optical oscillator according to an embodiment includes a first reflecting portion that transmits light having a first wavelength and reflects light having a second wavelength different from the first wavelength, a second reflecting portion that forms an unstable resonator together with the first reflecting portion and reflect light having the second wavelength, a laser medium that is disposed between the first reflecting portion and the second reflecting portion and emits light having the second wavelength due to incidence of light having the first wavelength, and a saturable absorption portion disposed on a side opposite to the first reflecting portion when viewed from the laser medium in the one direction, the first reflecting portion includes an incidence surface on which light having the first wavelength is incident, on a side opposite to the laser medium, a size of the second reflecting portion is smaller than a size of the first reflecting portion when viewed in the one direction, at least a part of a surface of the saturable absorption body on the side opposite to the laser medium includes a curved region curved toward the laser medium side, and the second reflecting portion is a dielectric multilayer film provided in the curved region. 1: An optical oscillator comprising:a first reflecting portion configured to transmit light having a first wavelength and reflect light having a second wavelength different from the first wavelength;a second reflecting portion configured to form an unstable resonator together with the first reflecting portion, be disposed apart from the first reflecting portion in one direction, and reflect light having the second wavelength;a laser medium disposed between the first reflecting portion and the second reflecting portion and configured to emit light having the second wavelength due to incidence of light having the first wavelength; anda saturable absorption portion disposed on a side opposite to the first reflecting portion ...

LASER APPARATUS FOR GENERATING EXTREME ULTRAVIOLET LIGHT

A system for generating extreme ultraviolet light, in which a target material inside a chamber is irradiated with a laser beam to be turned into plasma, includes a first laser apparatus configured to output a first laser beam, a second laser apparatus configured to output a pedestal and a second laser beam, and a controller connected to the first and second laser apparatuses and configured to cause the first laser beam to be outputted first, the pedestal to be outputted after the first laser beam, and the second laser beam having higher energy than the pedestal to be outputted after the pedestal. 1. A system for an extreme ultraviolet (EUV) light source , the system comprising a pre-pulse laser apparatus and a main pulse laser apparatus ,the pre-pulse laser apparatus configured to output a pre-pulse laser beam so as to turn a target into a diffused target, and a light generator configured to output an optical pulse;', 'an optical element configured to transform a waveform of the optical pulse;', 'a controller configured to determine a characteristic of the transformed waveform, the transformed waveform including a first portion and a second portion, the second portion having a temporal energy profile based on a temporal profile of the optical pulse and the first portion having a temporal energy profile that is different from the temporal energy profile of the optical pulse; and', 'an amplifier including a gain medium, the amplifier configured to amplify the first portion and the second portion to form a main pulse laser beam including an amplified first portion and an amplified second portion, the amplified first portion and the amplified second portion containing sufficient energy to turn the diffused target into a plasma that emits EUV light., 'the main pulse laser apparatus including2. The system according to claim 1 , wherein the diffused target has one of a disc-shape and a torus-shape.3. The system according to claim 1 , wherein the target has a droplet shape. ...

Pulse slicer in laser systems

An apparatus (such as a laser-based system) and method for providing optical pulses in a broad range of pulse widths and pulse energies uses a pulse slicer which is configured to slice a predefined portion having a desired pulse width of each of the one or more output optical pulses from a laser oscillator, in which timings of a rising edge and a falling edge of each sliced optical pulse relative to a time instance of a maximum of the corresponding each of the one or more output optical pulses from the laser oscillator, are chosen at least to maximize amplification efficiency of the optical amplifier, which may be located after the pulse slicer, and to provide the one or more amplified output optical pulses each having the desired pulse energy and pulse width.

LASER ASSEMBLY FOR AN OPTOACOUSTIC PROBE

A laser assembly is provided that includes a laser resonator that emits a first light having a first pulse width, and a trigger assembly electrically coupled to the laser resonator to actuate the laser resonator. The laser assembly also includes a sensor configured to detect the first light as the light emits from the laser resonator, and one or more processors coupled to the trigger assembly. The one or more processors are configured to obtain a first time delay interval from when the trigger assembly is actuated to when the sensor detects the first light, and actuate the laser resonator to emit a second light having a second pulse width based on the time delay interval determined. 1. A laser assembly comprising:a laser resonator that emits a first light having a first pulse width;a trigger assembly electrically coupled to the laser resonator to actuate the laser resonator;a sensor configured to detect the first light as the light emits from the laser resonator; obtain a first time delay interval from when the trigger assembly is actuated to when the sensor detects the first light; and', 'actuate the laser resonator to emit a second light having a second pulse width based on the time delay interval determined., 'one or more processors coupled to the trigger assembly and configured to2. The laser assembly of claim 1 , wherein the one or more processors are further configured to:obtain a first full width half max pulse width of the first light; andactuate the laser resonator to emit the second light having the second pulse width based on the first full width half max pulse width.3. The laser assembly of claim 2 , wherein the one or more processors actuate the laser resonator to emit the second light based on a proportion between the time delay and the first full width half max pulse width.4. The laser assembly of claim 2 , wherein the one or more processors are further configured to:determine a first pulse-width controller input based on the first full width half max ...

HIGH ENERGY NANOSECOND PULSED FIBER LASER BASED ON INCOHERENT BEAM COMBINATION

An incoherent beam combination based high energy nanosecond pulsed fiber laser includes a nanosecond pulsed seed, a fiber splitter, fiber amplifiers, synchronization fibers, a fiber laser combiner and a laser output head. The output fiber of the pulsed seed is fusion spliced to the input fiber of the splitter; the output fibers of the splitter are fusion spliced to the fiber amplifiers separately; synchronization fibers are fusion spliced between the amplifiers and the input fibers of the fiber laser combiner. The nanosecond pulsed seed is split by the fiber splitter and amplified in the later fiber amplifiers; synchronization fibers make sure the optical time-domain synchronization; the fiber laser combiner allows for the incoherent combination of high energy pulsed laser. 1. An incoherent beam combination based nanosecond pulsed fiber laser , comprising: a nanosecond pulsed seed , a fiber splitter , fiber amplifiers , synchronization fibers , a fiber laser combiner and a laser output head; wherein an output fiber of the pulsed seed is fusion spliced to the input fiber of the splitter , output fibers of the splitter are fusion spliced to the fiber amplifiers separately; synchronization fibers are fusion spliced between the amplifiers and an input fibers of the fiber laser combiner , the nanosecond pulsed seed is split by the fiber splitter and amplified in the later fiber amplifiers; synchronization fibers are configured for optical time-domain synchronization; and the fiber laser combiner allows the incoherent combination of high energy pulsed laser.2. The fiber laser of claim 1 , wherein said nanosecond pulsed seed is an actively Q-switch fiber laser claim 1 , including a pump diode claim 1 , a signal pump fiber combiner claim 1 , double cladding Yb doped fiber claim 1 , high-reflection (HR) fiber grating claim 1 , fiber coupled acousto-optic modulator (AOM) claim 1 , partial-reflection (PR) fiber grating and fiber optic isolator claim 1 , the pump diode is ...

LASER APPARATUS AND METHOD FOR GENERATING OPTICAL PULSES BASED ON Q-SWITCHING MODULATED WITH A 2-D SPATIAL LIGHT MODULATOR

A laser apparatus and method are provided for generating optical pulses based on Q-switching controllable with a fast and reliable two-dimensional (2-D) spatial light modulator, such as a digital micro-mirror device (DMD). Temporal and spatial modulation may be applied to selectively control the Q-switching provided by the spatial light modulator. The apparatus and method may be optionally optimized with straightforward optical components to increase angular magnification of a beam incident on the spatial light modulator and thus effectively reduce the Q-switching time. 1. A laser apparatus for generating optical pulses comprising:a laser cavity;a spatial light modulator comprising a two-dimensional array of pixels arranged to provide Q-switching at a pixel level in the laser cavity; anda controller connected to the spatial light modulator to temporally and spatially modulate the two-dimensional array of pixels to selectively control the Q-switching provided by the spatial light modulator.2. The laser apparatus of claim 1 , wherein the two-dimensional array of pixels comprises a two-dimensional array of rotatable micro-mirrors.3. The laser apparatus of claim 2 , further comprising at least one optical element arranged to provide angular magnification to beams incident on the two-dimensional array of micro-mirrors claim 2 , the angular magnification effectively increasing a switching speed of the two-dimensional array of micro-mirrors.4. The laser apparatus of claim 3 , wherein said least one optical element comprises a non-curved optical element selected from the group consisting of a mirror claim 3 , a prism and a combination of two or more of said non-curved optical elements.5. The laser apparatus of claim 2 , further comprising a telescope arranged to provide angular magnification and spread a cross-section of beams incident on the two-dimensional array of micro-mirrors claim 2 , the angular magnification effectively increasing a switching speed of the two- ...

Solid-state laser

A solid-state laser has an amplifying laser medium for producing a laser beam and a pump device that has at least one laser diode and that produces a pump radiation that impinges on a first side face of the laser medium, which side face is parallel to a z axis and parallel to a y axis that is at right angles to the z axis. On a second side face, which is opposite the first side face, the laser medium is cooled by a heat sink. The length of a y−1/e2 region of the pump radiation is shorter than the length of the first side face of the laser medium in the direction of the y axis, wherein the y−1/e2 region of the pump radiation denotes a section of the y axis over which the intensity of the pump radiation on the first side face of the laser medium has a value that is more than the maximum intensity of the pump radiation on the first side face of the laser medium divided by e2. The length of a y cooling region, which length denotes a section of the y axis, over which a cooling strip extends is less than 70% and greater than 50% of the length of a y pump region of the laser medium, wherein the y pump region denotes a section of the y axis over which 80% of the total power of the pump radiation that is absorbed by the laser medium is absorbed and at the two ends of which the intensity of the pump radiation is of equal magnitude.

OBJECT INFORMATION ACQUIRING APPARATUS AND LASER APPARATUS

An object information acquiring apparatus is used which includes: a laser medium; a temperature controlling unit for controlling a temperature of the laser medium; an excitation unit for exciting the laser medium; a control unit for controlling the temperature controlling unit and the excitation unit; a probe for receiving acoustic waves that are generated when an object is irradiated with a laser beam from the laser medium; and a processing unit for acquiring characteristic information relating to the object from the acoustic waves, wherein the control unit does not operate the excitation unit until the temperature of the laser medium falls within a predetermined range. 18.-. (canceled)9. A laser apparatus , comprising:a laser medium;temperature controlling means configured to control a temperature of the laser medium;excitation means configured to excite the laser medium;control means configured to control the temperature controlling means and the excitation means;first temperature measuring means configured to measure a first temperature of the laser medium; andsecond temperature measuring means configured to measure a second temperature of a substance which is circulated near the laser medium for heating the laser medium,wherein the control means is configured to control the excitation means based on the first temperature and the second temperature.10. The laser apparatus according to claim 9 , wherein the control means is configured not to activate the excitation means until the first temperature reaches a first predetermined value.11. The laser apparatus according to claim 10 , wherein the first predetermined value is 80 degrees Celsius.12. The laser apparatus according to claim 9 , wherein the control means is configured not to activate the excitation means until the second temperature reaches a second predetermined value.13. The laser apparatus according to claim 12 , wherein the second predetermined value is larger than 20 degrees Celsius and smaller than ...

SIGNAL TO NOISE RATIO MANAGEMENT

The subject matter of this specification can be embodied in, among other things, a method for remotely sensing vibration includes transmitting a collection of optical pulses through an optical fiber at a predetermined frequency, detecting a collection of backscattered Rayleigh traces from the optical fiber based on a vibration of the optical fiber at a vibration frequency at a location along the optical fiber, determining a normalized differential trace based on the collection of Rayleigh traces, determining, based on the normalized differential trace, the location in the optical fiber of the vibration, and determining, based on the raw Rayleigh traces, the vibration frequency. 1. A method for remotely sensing vibration , comprising:transmitting a plurality of optical pulses through an optical fiber at a predetermined frequency;detecting a plurality of backscattered Rayleigh traces from the optical fiber based on a vibration of the optical fiber at a vibration frequency at a location along the optical fiber;determining a normalized differential trace based on the collection of Rayleigh traces;determining, based on the normalized differential trace, the location in the optical fiber of the vibration; anddetermining, based on the raw Rayleigh traces, the vibration frequency.2. The method of claim 1 , wherein the collection of optical pulses is transmitted at a predetermined frequency claim 1 , and the vibration frequency is determined up to substantially the Nyquist frequency of the predetermined frequency.3. The method of claim 1 , wherein determining the normalized differential trace based on the plurality of Rayleigh traces further comprises determining the normalized differential trace (ΔR) based on a predetermined number (N) of Rayleigh traces (R) as ΔR=(R−R)/R claim 1 ,i ∈[1 claim 1 , N−1].4. The method of claim 1 , wherein transmitting a plurality of optical pulses through an optical fiber at a predetermined frequency comprises:generating, by a light source, ...

Method and system for mutliline mir-ir laser

A method of performing spatial separation of different wavelengths in a single laser cavity includes generating, from a pump radiation source, pump radiations in spatially separate channels and focusing the generated pump radiations in the spatially separate channels towards an active gain medium having amplification spectra. The method also includes emitting from the active gain medium, amplified radiations of the spatially separate channels, each channel of the spatially separate channels representing a corresponding wavelength and focusing the emitted amplified radiations of the spatially separated channels towards an aperture. The method further includes suppressing, at the aperture, an off-axis mode of the amplified radiations of the spatially separate channels, diffracting the amplified radiations of the spatially separate channels received through the aperture to provide diffracted radiations and returning a portion of the diffracted radiations back to the aperture, and collimating the diffracted radiations of the spatially separate channel.

Solid-state laser device and photoacoustic measurement device

Disclosed are a solid-state laser device having an advantage of achieving simplification of a configuration and reduction in size, and a photoacoustic measurement device. In a solid-state laser device which accommodates a solid-state laser medium and an excitation light source having a rod-shaped portion, the excitation light source is provided to be pulled out of a laser chamber. An optical element which bends light is provided at a position separated from the rod-shaped portion such that at least a part of the optical element and at least a part of the rod-shaped portion are at the same position in the longitudinal direction of the rod-shaped portion. One resonator mirror is disposed at a position where bent light is incident. Optical components between the optical element and the resonator mirror are provided at positions separated from a path along which the excitation light source is pulled out.

LASER APPARATUS USING CAVITY DUMPING AND ACTIVE MODE LOCKING

This invention provides a solution for operating a mode-locking and cavity dumping laser apparatus using a single electro-optical switch or modulator, such as a Pockels cell, without the need of multiplexing between two sources of voltage. The complex waveform of electrical signal, which controls the Pockels Cell is achieved by employing the phenomena, called LC circuit ringing, where the LC circuit is formed from an inductive element and a capacitor, where the Pockels Cell works as a capacitor itself. The ringing frequency should be calculated such that the period of oscillations is preferably two times longer than the round-trip time of a light pulse inside the optical cavity. As a result, optical losses are created inside the cavity with a period, which coincides with the travel of a light pulse, thus the pulse build-up is consistent and stable. 1. A laser apparatus comprising:an optical cavity;a gain medium; andat least one of an electro-optical switch and a modulator configured to change a polarization state of a beam inside the optical cavity, wherein the at least one of the electro-optical switch and the modulator is configured to be controlled by means of an electrical signal having at least two states of bias voltage, wherein at least one of the two states comprises voltage oscillations, and wherein the voltage oscillations are configured to be initiated at a moment of switching between the at least two states and are determined and supported by means of a passive LC circuit configured to generate the voltage oscillations through a ringing phenomena at a frequency corresponding to a resonance frequency of the LC circuit.2. The laser apparatus according to claim 1 , wherein the at least one of the electro-optical switch and the modulator comprises a Pockels Cell combined with a polarizer claim 1 , and wherein the Pockels Cell is configured to act as a capacitor in the LC circuit claim 1 , to create the voltage oscillations.3. The laser apparatus according to ...

Q-SWITCHED SOLID-STATE LASER

In a Q-switched solid-state laser having a resonator () in the form of a linear resonator or a ring resonator having an active laser material () and at least one first and one second mirror () and a resonator length (a) of less than 50 mm, preferably less than 25 mm, in the case of the configuration as a linear resonator and of less than 100 mm, preferably less than 50 mm, in the case of the configuration as a ring resonator, at least substantially only one longitudinal mode oscillates in the resonator (). The resonator () is in the form of an unstable resonator, with one of the mirrors () being a gradient mirror. 1330145333045. A Q-switched solid-state laser comprising a resonator ( , ) form as a linear resonator or a ring resonator having an active laser material () and at least one first and one second mirror ( , ) and a resonator length (a) of less than 50 mm in case of the linear resonator and of less than 100 mm in case of the ring resonator , with at least substantially only one longitudinal mode oscillating in the resonator () , wherein the resonator ( , ) is an unstable resonator , with one of the first or second mirrors ( , ) being a gradient mirror.23303333030. The solid-state laser as claimed in claim 1 , wherein a total refractive power of the resonator ( claim 1 , ) claim 1 , which is obtained claim 1 , in the case of the linear resonator () claim 1 , from a sum of refractive powers of optical elements of the resonator () over a path in one direction and a return path of the resonator () and claim 1 , in the case of the ring resonator claim 1 , from a sum of refractive powers of optical elements of the resonator () through a round-trip around the resonator () claim 1 , is less than −2 dpt.31330. The solid-state laser as claimed in claim 2 , wherein an absolute value of a refractive power of a thermal lens that is formed by the active laser material () during operation is less than 10% of an absolute value of the total refractive power of the resonator ...

FIBER-BASED OPTICAL MODULATOR

Methods, apparatus, and systems for modulation of a laser beam. An optical modulator may comprise an optical input to receive an optical beam, and one or more lengths of fiber between the optical input and an optical output. At least one of the lengths of fiber comprises a confinement region that is optically coupled to the output. The optical modulator may further comprise a perturbation device to modulate, through action upon the one or more lengths of fiber, a transmittance of the beam through the confinement region from a first transmittance level at a first time instance to a second transmittance level at a second time instance. The optical modulator may further comprise a controller input coupled to the perturbation device, wherein the perturbation device is to act upon the one or more lengths of fiber in response to a control signal received through the controller input. 1. An optical modulator , comprising:an optical input to receive an optical beam;one or more lengths of fiber between the optical input and an optical output, wherein at least one of the lengths of fiber comprises a confinement region that is optically coupled to the output;a perturbation device to modulate, through action upon the one or more lengths of fiber, a transmittance of the beam through the confinement region from a first transmittance level at a first time instance to a second transmittance level at a second time instance; anda controller input coupled to the perturbation device, wherein the perturbation device is to act upon the one or more lengths of fiber in response to a control signal received through the controller input.2. The optical modulator of claim 1 , wherein an optical power transmitted by the confinement region to the optical output at the first time is at least 10% greater than the optical power transmitted through the confinement region to the optical output at the second time.3. The optical modulator of claim 1 , wherein the action upon the one or more lengths of ...

METHODS OF MODULATING MICROLASERS AT ULTRALOW POWER LEVELS, AND SYSTEMS THEREOF

A microlaser system includes an optical source, a microlaser, an actuator switch, and a photovoltaic power source. The microlaser, which includes a control element, is optically pumped by at least a portion of light emitted by the optical source. The actuator switch is configured to be activated by a triggering event. Furthermore, the photovoltaic power source is coupled in a series connection with the actuator switch and the control element, the series connection configured to connect the photovoltaic power source to the control element of the microlaser when the actuator switch is activated by the triggering event. 1. A method of operation comprising:directing light upon a microlaser for optically pumping the microlaser; anddetecting the occurrence of a triggering event based on a change in an optical output of the microlaser, the change in optical output occurring in response to connecting a photovoltaic power source to the microlaser only upon occurrence of the triggering event.2. The method of claim 1 , further comprising:reducing power consumption by disconnecting the photovoltaic power source from the microlaser during an absence of the triggering event.3. The method of claim 2 , wherein directing light upon the microlaser comprises using a light source to direct a first portion of light upon the microlaser and a second portion of light upon the photovoltaic power source.4. The method of claim 3 , wherein connecting the photovoltaic power source to the microlaser comprises connecting the photovoltaic power source to one of: a) a heater element located in the microlaser claim 3 , b) a diode assembly located in the microlaser claim 3 , c) a piezoelectric assembly located in the microlaser claim 3 , or d) a capacitive assembly located in the microlaser.5. A method of operation comprising:directing light upon a microlaser for optically pumping the microlaser; andconnecting a photovoltaic power source to modify an operational condition of the microlaser only upon ...

APPARATUS AND METHOD FOR MEASURING CONCENTRATION OF POLLUTANTS IN WATER

The present disclosure provides an apparatus and a method for measuring a concentration of pollutants in water. A passive Q-switched fiber laser outputs an evanescent wave to a to-be-tested water sample after emitting a Q-switched pulse laser signal and transmitting it via an evanescent field fiber, and based on an evanescent wave change caused by an absorption effect of the pollutants in the to-be-tested water sample to the evanescent wave and an output repetition frequency change of the passive Q-switched fiber laser due to the evanescent wave change, outputs an output repetition frequency result of the passive Q-switched fiber laser. The method is simple; and the apparatus based on the method is simple in structure and low in cost. 1. An apparatus for measuring a concentration of pollutants in water , comprising a passive Q-switched fiber laser , an evanescent field fiber and a spectrum apparatus;wherein the evanescent field fiber is disposed in a laser resonant cavity of the passive Q-switched fiber laser, and the passive Q-switched fiber laser is connected with the spectrum apparatus;the passive Q-switched fiber laser is configured to output an evanescent wave to a to-be-tested water sample after emitting a Q-switched pulse laser signal and transmitting the Q-switched pulse laser signal via an evanescent field fiber;the passive Q-switched fiber laser is further configured to output an output repetition frequency result of the passive Q-switched fiber laser based on an evanescent wave change caused by an absorption effect of the pollutants in the to-be-tested water sample to the evanescent wave and an output repetition frequency change of the passive Q-switched fiber laser due to the evanescent wave change; andthe spectrum apparatus is configured to display the output repetition frequency result of the passive Q-switched fiber laser.2. The apparatus according to claim 1 , wherein the spectrum apparatus is further configured to determine the concentration of the ...

Fiber-based saturable absorber

Methods, apparatus, and systems for active saturable absorbance of an optical beam. An active saturable absorber may comprise an optical input to receive an optical beam, and one or more lengths of fiber between the optical input and an optical output. At least one of the lengths of fiber comprises a confinement region that is optically coupled to the output. The active saturable absorber may further comprise an optical detector to sense a characteristic of the optical beam, such as power. The active saturable absorber may further comprise a perturbation device to modulate, through action upon the one or more lengths of fiber, a transmittance of the beam through a fiber confinement region from a lower transmittance level to a higher transmittance level based on an indication of the characteristic sensed while the transmittance level is low.

Picosecond Laser Apparatus And Methods For Its Operation and Use

Apparatuses and methods are disclosed for applying laser energy having desired pulse characteristics, including a sufficiently short duration and/or a sufficiently high energy for the photomechanical treatment of skin pigmentations and pigmented lesions, both naturally-occurring (e.g., birthmarks), as well as artificial (e.g., tattoos). The laser energy may be generated with an apparatus having a resonator with the capability of switching between a modelocked pulse operating mode and an amplification operating mode. The operating modes are carried out through the application of a time-dependent bias voltage, having waveforms as described herein, to an electro-optical device (e.g., a Pockels cell) positioned along the optical axis of the resonator. 1. (canceled)2. A method for treating a skin pigmentation comprising pigment particles using a photomechanical process , the method comprising exposing at least one pigment particle to pulsed laser energy generated using Nd:YAG , titanium doped sapphire (TIS) crystal , or alexandrite as a lasing medium and with pulses having a duration that is a multiple of the acoustic transit time across said pigment particle to photomechanically disrupt the pigment particle.3. The method of wherein said pulses have an energy of at least 100 mj.4. The method of wherein said duration is less than 1 nanosecond.5. The method of wherein said duration is at most 500 ps.6. The method of wherein said pulses have a duration of between 100 ps and 300 ps.7. The method of wherein said pulses have a duration of between 100 ps and 500 ps.8. The method of wherein the duration is below twice the acoustic transit time across said pigment particle.9. The method of wherein the duration is below five times the acoustic transit time across said pigment particle.10. The method of wherein the duration is from two times to five times the acoustic transit time across the pigment particle.11. The method of wherein the pigment particle is in one of a tattoo claim ...

LASER DEVICE AND PHOTOACOUSTIC MEASUREMENT DEVICE

Disclosed are a laser device which uses alexandrite crystal and is capable of suppressing abnormal oscillation even if the size thereof is reduced and suppressing damage to an AR coating on a Q switch or alexandrite crystal, and a photoacoustic measurement device. A laser rod includes alexandrite crystal. A flash lamp irradiates the laser rod with excitation light. A resonator includes a pair of mirrors and with the laser rod sandwiched therebetween. A Q switch is inserted into the optical path of the resonator and controls the Q value of the resonator. A polarizer is inserted into the resonator and is a non-coated Brewster polarizer which selectively transmits light in a predetermined polarization direction among light emitted from the laser rod. 1. A laser device comprising:a laser rod which includes alexandrite crystal;an excitation light source which irradiates the laser rod with excitation light;a resonator which includes a pair of mirrors with the laser rod sandwiched therebetween;a Q switch which is inserted into the optical path of the resonator and controls the Q value of the resonator; anda non-coated Brewster polarizer which is inserted at least between the laser rod and the Q switch or between the laser rod and one of the pair of mirrors and selectively transmits light in a predetermined polarization direction among light emitted from the laser rod.2. The laser device according to claim 1 ,wherein the optical path of the resonator is sealed within the range of the resonator.3. The laser device according to claim 1 ,wherein at least one of the laser rod or the Q switch has an anti-reflection film at a light incidence end thereof.4. The laser device according to claim 2 ,wherein at least one of the laser rod or the Q switch has an anti-reflection film at a light incidence end thereof.5. The laser device according to claim 1 ,wherein the Q switch includes a Pockels cell, in a case in which an applied voltage to the Pockels cell is a first voltage, the Q ...

Voltage-controllable laser output coupler for integrated photonic devices

A voltage-controllable output coupler for a laser, comprising: a liquid crystal cell that provides a change in birefringence in response to an applied voltage; and a polariser oriented with respect to the liquid crystal cell to collectively form a variable reflectance mirror for the laser; wherein output coupling of the laser is controllable by applying voltage to the liquid crystal cell for a switching interval to switch the variable reflectance mirror from high reflectance to low reflectance, and vice versa, thus actively Q-switching or cavity dumping the laser.

DIODE-PUMPED SOLID-STATE LASER APPARATUS FOR LASER ANNEALING

Laser annealing apparatus includes a plurality of frequency-tripled solid-state lasers, each delivering an output beam of radiation at a wavelength between 340 nm and 360 nm. Each output beam has a beam-quality factor (M) greater of than 50 in one transverse axis and greater than 20 in another transverse axis. The output beams are combined and formed into a line-beam that is projected on a substrate being annealed. Each output beam contributes to the length of the line-beam. 1. Optical apparatus for annealing a layer on a substrate , comprising:{'sup': 2', '2, 'a plurality of frequency-converted repetitively-pulsed solid-state lasers, each thereof delivering an output beam having a wavelength in the ultraviolet region of the electromagnetic spectrum, each output beam having a cross-section characterized by mutually-orthogonal first and second transverse axes, a beam-quality factor Min the first transverse axis greater than about 50, a beam-quality factor Min the second transverse axis greater than about 20, laser pulses having a pulse-energy greater than about 100 millijoules, and a pulse-repetition frequency greater than about 100 hertz; and'}a line-projector arranged to receive the output beams, form the output beams into a line-beam, and project the line-beam onto the layer, the line-beam having a length and a width on the layer.2. The apparatus of claim 1 , wherein the beam-quality factor Min the first transverse axis is greater than about 200.3. The apparatus of claim 1 , wherein each output beam contributes to the entire length of the line-beam.4. The apparatus of claim 1 , wherein each of the frequency-converted repetitively-pulsed solid-state lasers includes a laser-resonator having a gain-element optically pumped by one or more diode-laser arrays arranged to provide a gain volume in the gain-element having first and second dimensions in respectively the first and second transverse axes.5. The apparatus of claim 4 , wherein the first transverse axis ...

LASER DEVICE AND EXTREME ULTRAVIOLET LIGHT GENERATION DEVICE

A laser device includes: a master oscillator () configured to output a pulse laser beam (L) based on a light emission trigger signal (S); a delay circuit () configured to generate a switching signal (S) after a predetermined delay time has elapsed since reception of the light emission trigger signal (S); a high voltage switch () configured to generate a high voltage pulse based on the switching signal (S); an optical shutter () positioned on the optical path of the pulse laser beam (L) and driven based on the high voltage pulse; and a high voltage monitor () configured to detect the high voltage pulse and transmit a high voltage pulse sensing signal (S) to the delay circuit (). The delay circuit () determines the delay time based on the light emission trigger signal (S) and the high voltage pulse sensing signal (S). 1. A laser device comprising:a laser control unit configured to generate a light emission trigger signal;a master oscillator configured to output a pulse laser beam based on the light emission trigger signal transmitted from the laser control unit;a delay circuit configured to receive the light emission trigger signal transmitted from the laser control unit and generate a switching signal after a predetermined delay time has elapsed since the reception;a high voltage switch configured to generate a high voltage pulse based on the switching signal transmitted from the delay circuit;an optical shutter positioned on an optical path of the pulse laser beam output from the master oscillator and driven based on the high voltage pulse output from the high voltage switch; anda high voltage monitor configured to detect the high voltage pulse output from the high voltage switch and transmit a high voltage pulse sensing signal to the delay circuit,the delay circuit determining the delay time based on the light emission trigger signal and the high voltage pulse sensing signal.2. The laser device according to claim 1 , wherein claim 1 , when B represents a target ...

REGENERATIVE OPTICAL AMPLIFIER FOR SHORT PULSED LASERS, A LASER SOURCE AND A LASER WORKSTATION

This invention provides a solution for operating a regenerative amplifier using a single electro-optical device, such as a Pockels cell. An efficient cavity geometry of a regenerative amplifier is provided for enabling pulse selection, coupling and releasing to an output by operating a single Pockels cell unit placed essentially in the middle of the optical cavity, between two polarizers, whereas a first polarizer is used for release of an amplified pulse and a second polarizer is used for injection of seed pulses and release of at least one of waste amplified pulses and seed pulses. One side of the cavity, with respect to the location of said Pockels cell, includes an empty space, whereas the other side is provided with a gain medium, which is pumped by a pump source. The regenerative amplifier of such optical design is both efficient and cost effective. The single electro-optical unit works both as the control unit for operating the regenerative amplifier and as an output pulse picker unit. 1. A regenerative optical amplifier comprising:an optical cavity defined by two end mirrors, andan electro-optical unit arranged to change a polarization state of an incident beam upon application of an electric signal,wherein the electro-optical unit is located essentially in the middle of the optical cavitywherein a length of each of a first and a second optical path, extending from the electro-optical unit towards the end mirrors is long enough so that the electro optical unit is able to fully transition from one state to another while a pulse of light is propagating in either of the first and the second optical paths, andwherein the regenerative optical amplifier is arranged in such a manner that, depending on a timing of a control signal of the electro-optical unit, amplified pulses are directed towards one of two outputs of the regenerative optical amplifier, located on opposite sides with respect to the electro-optical unit.2. The regenerative optical amplifier according ...

Method for Operating a Laser System

In a method for operating a laser system in a Q-switched mode, the laser system provided with a laser resonator with a laser medium and an electro-optical modulator, wherein the electro-optical modulator has an EOM crystal, wherein the EOM crystal has a characteristic ringing time (t) when subjected to acoustic ringing, the EOM crystal is driven by modulator voltage pulses (p) having a modulator voltage pulse duration (t). A train of at least two subsequent laser pulses (p) is generated. The modulator voltage pulse duration (t)is selected to be at least approximately equal to the characteristic ringing time (t) of the EOM crystal multiplied by an integer factor. 1. A method for operating a laser system in a Q-switched mode , the laser system comprising a laser resonator with a laser medium and an electro-optical modulator , wherein the electro-optical modulator comprises an EOM crystal , wherein the EOM crystal has a characteristic ringing time (t) when subjected to acoustic ringing , the method comprising:{'sub': m', 'ml, 'driving the EOM crystal by modulator voltage pulses (p) having a modulator voltage pulse duration (t);'}{'sub': 'l', 'generating a train of at least two subsequent laser pulses (p);'}{'sub': ml', '0, 'selecting the modulator voltage pulse duration (t) to be at least approximately equal to the characteristic ringing time (t) of the EOM crystal multiplied by an integer factor.'}2. The method according to claim 1 , wherein the modulator voltage pulses (p) are at least approximately square shaped.3. The method according to claim 1 , selecting the integer factor for multiplying the characteristic ringing time (t) of the EOM crystal to be 1.4. The method according to claim 1 , wherein an initial slope of a single modulator voltage pulse (p) excites ringing of the EOM crystal at amplitudes (a) claim 1 , including an initial amplitude at a starting time (t)and a dampened limit amplitude at a limit time (t); the method further comprising:{'sub': '0.8', ' ...

Q-SWITCHED ALL-FIBER LASER

A Q-switched all-fiber laser has a long period fiber grating (LPFG) switch with optical spectral characteristics that are controlled by application of stress. An actuator applies stress to selected sections of the LPFG in order to switch a fiber laser cavity at a specified wavelength. A controller controls the application of stress in the time domain, thereby switching the Q-factor of the fiber laser cavity. 1. A fiber laser apparatus configured to generate Q switched optical pulses , comprising:a first fiber Bragg grating having a first reflective center wavelength;a second fiber Bragg grating having a second reflective center wavelength, the second reflective center wavelength being in a reflective wavelength bandwidth of the first fiber Bragg grating, the first and second fiber Bragg gratings configured to provide optical feedback for laser oscillation and to confine laser oscillation wavelength;at least one long period fiber grating disposed between the first fiber Bragg grating and the second fiber Bragg grating, the long period fiber grating having a switching wavelength in which switching wavelength bandwidth fully covers the wavelength bandwidth of the first fiber Bragg grating and the second fiber Bragg grating;a gain fiber disposed between the first fiber Bragg grating and the second fiber Bragg grating, the gain fiber configured to provide optical gain; andat least one actuator configured to apply stress to the long period fiber grating to cause switching of Q factor of the laser cavity and generation of Q switched optical pulses.2. The fiber laser of wherein the actuator causes temporary deformation of the long period fiber grating claim 1 , resulting in a change of effective refractive index.3. The fiber laser of further comprising a controller which controls the actuator such that the stress is applied in a periodic time varying manner.4. The fiber laser of wherein the actuator applies the stress acoustically.5. The fiber laser apparatus of further ...

EXCITING A CRYSTAL OF A POCKELS CELL

A Pockels cell utilizes high-voltage pulses for a polarization adjustment of electromagnetic radiation passing through the crystal, in particular laser radiation. The polarization adjustment involves applying a sequence of useful voltage pulses (N) to the crystal, each having a useful period duration (TP, N) and a useful pulse width (TN), and induces birefringence of the crystal via electric polarization in the crystal for polarization adjustment of the electromagnetic radiation. A sequence of compensation pulses (K, K1, K2) are applied to the crystal, each having a voltage curve, wherein the sequence is temporally overlaid by the sequence of useful voltage pulses (N) so that the voltage curves of the compensation pulses (K, K1, K2) counteract the inducing of a mechanical vibration in the crystal of the Pockels cell by the useful voltage pulses (N). 1. A method for exciting a crystal of a Pockels cell with high-voltage pulses for polarization setting of laser radiation passing through the crystal , comprising:{'sub': P', 'N, 'applying a sequence of use voltage pulses (N) to the crystal which each have a use period duration (T, N) and a use pulse width (T) and are configured to induce birefringence of the crystal via an electrical polarization in the crystal for the polarization setting of the laser radiation, and'}applying a sequence of compensation pulses (K, K1, K2), which each have a voltage profile, to the crystal, the sequence of compensation pulses (K, K1, K2) being overlaid in time with the sequence of use voltage pulses (N) such that the voltage profiles of the compensation pulses (K, K1, K2) counteract an excitation of a mechanical oscillation in the crystal of the Pockels cell by the use voltage pulses (N).2. The method of claim 1 , whereinswitching edges of the voltage profiles of the compensation pulses (K, K1, K2) are configured as mechanically acting portions of the voltage profiles of the compensation pulses (K, K1, K2) such that their temporal ...

Solid-state laser system

A method of operating a q-switch RE,XAB laser includes: providing a pump bias current to a pump source, the pump source directed to an RE:XAB gain medium, the RE:XAB gain medium within a resonator cavity, where X is selected from Ca, Lu, Yb, Nd, Sm, Eu, Gd, Ga, Tb, Dy, Ho, Er, and where RE is selected from Lu, Y, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Pr, Tm, Cr, Ho, with a bias current level below a lasing threshold of the RE:XAB gain medium; providing a pump pulse to the gain medium, the pump pulse of the lasing threshold of the RE:XAB gain medium, the pump pulse causing the RE:XAB gain medium to emit a laser pulse; and reducing the pump bias current to at least below the gain medium lasing threshold, the combination of the pump bias, the pump pulse, and the pump reduction having a current profile.

PHOTOACOUSTIC MEASUREMENT DEVICE AND LASER LIGHT SOURCE

A flash lamp excites a laser rod A Q switch which changes the loss of the optical resonator according to the voltage applied is inserted on the optical path of a pair of mirrors and forming the optical resonator. An optical path shutter is provided on the optical path of laser emission light. In a first operation mode in which laser emission is performed, the optical path shutter is opened and the voltage applied to the Q switch is changed from a high voltage to, for example, 0 V to emit pulsed laser light after the flash lamp excites the laser rod In a second operation mode in which the laser emission is interrupted and waited for, the optical path shutter is closed and the voltage applied to the Q switch is, for example, 0 V. 1. A photoacoustic measurement device comprising:a laser medium;an excitation unit that excites the laser medium;an optical resonator including a pair of mirrors that face each other with the laser medium interposed therebetween;a Q switch that is provided on an optical path of the optical resonator and changes optical loss of the optical resonator, according to a voltage applied, such that the optical loss of the optical resonator when a first voltage is applied to the Q switch is more than the optical loss of the optical resonator when a second voltage lower than the first voltage is applied to the Q switch;a laser light source that is provided on an optical path of laser emission light and has an optical path shutter which switches the transmission and blocking of the laser emission light;an acoustic wave detection unit that, after light is emitted from the laser light source to a subject, detects a photoacoustic wave generated by the emission of the light;a photoacoustic signal processing unit that performs signal processing for the photoacoustic wave; anda control unit that performs control such that, in a first operation mode in which laser emission is performed, the optical path shutter transmits the light from the laser light source ...

SOLID-STATE LASER DEVICE, SOLID-STATE LASER SYSTEM, AND LASER DEVICE FOR EXPOSURE DEVICE

A solid state laser device includes a seed laser that outputs continuous wave laser seed light, a light intensity changeable unit that changes a light intensity thereof and outputs seed pulse light, a CW excitation laser that outputs continuous wave excitation light, an amplifier that amplifies the seed pulse light and outputs amplified light based on an amplification gain increased by the excitation light, a wavelength conversion unit that converts a wavelength of the amplified light and outputs harmonic light, and a light intensity control unit that allows the light intensity changeable unit to output the seed pulse light after a certain time elapsed from an input of an external trigger signal each time the signal is input and output suppression light that suppresses an increase of the amplification gain in a period after an output of the seed pulse light until an input of a next external trigger signal. 1. A method for generating pulse laser light including:amplifying first seed pulse laser light based on an amplification gain increased with continuous wave excitation light after a first delay time elapsed from an input of a first trigger signal to generate first amplified light;after generation of the first seed pulse laser light, amplifying second seed pulse laser light based on the amplification gain after a second delay time elapsed from an input of a second trigger signal to generate second amplified light;generating first suppression light that suppresses an increase of the amplification gain in a period after the first delay time until the input of the second trigger signal;converting a wavelength of the first amplified light to generate first harmonic light; andconverting a wavelength of the second amplified light to generate second harmonic light.2. The method according to claim 1 , further includinggenerating the first seed pulse laser light and the second seed pulse laser light by changing a light intensity of continuous wave laser light.3. The method ...

PHOTOACOUSTIC MEASUREMENT DEVICE AND LASER LIGHT SOURCE

A flash lamp excites a laser rod . A Q switch which changes the loss of the optical resonator according to the voltage applied is inserted on the optical path of a pair of mirrors and forming the optical resonator. An optical path shutter is provided on the optical path of laser emission light. In a first operation mode in which laser emission is performed, the optical path shutter is opened and the voltage applied to the Q switch is changed from a high voltage to, for example, 0 V to emit pulsed laser light after the flash lamp excites the laser rod . In a second operation mode in which the laser emission is interrupted and waited for, the optical path shutter is closed and the voltage applied to the Q switch is, for example, 0 V. 1. A photoacoustic measurement device comprising:a laser medium;an excitation unit that excites the laser medium;an optical resonator including a pair of mirrors that face each other with the laser medium interposed therebetween;a Q switch that is provided on an optical path of the optical resonator and changes optical loss of the optical resonator, according to a voltage applied, such that the optical loss of the optical resonator when a first voltage level is applied to the Q switch is more than the optical loss of the optical resonator when a second voltage level lower than the first voltage level is applied to the Q switch;a laser light source that is provided on an optical path of laser emission light and has an optical path shutter;an acoustic wave detection unit that, after light is emitted from the laser light source to a subject, detects a photoacoustic wave generated by the emission of the light;a photoacoustic signal processing unit that performs signal processing for the photoacoustic wave; anda control unit that performs control such that, in a first operation mode in which laser emission is performed, the optical path shutter transmits the light from the laser light source and the voltage applied to the Q switch is changed ...

SINGLE PULSE LASER APPARATUS

Disclosed herein is a single pulse laser apparatus that includes: a resonator having a first mirror, a second mirror, a gain medium, an electro-optic modulator (EOM) configured to perform single pulse switching, and an acousto-optic modulator (AOM) configured to perform mode-locking; a photodiode configured to measure a laser beam oscillated in the resonator; a synchronizer configured to convert an electrical signal, which is generated by measuring the laser beam, into a transistor-transistor logic (TTL) signal; a delay unit configured to set a delay time for the TTL signal to synchronize the EOM and the AOM and output a trigger TTL signal according to the delay time; an AOM driver configured to input the trigger TTL signal to the AOM that performs mode-locking and drive the AOM; and an EOM driver configured to input the trigger TTL signal to the EOM that performs single pulse switching and drive the EOM. 1. A single pulse laser apparatus including a resonator having a first mirror , a second mirror , a gain medium , an electro-optic modulator (EOM) configured to perform single pulse switching , and an acousto-optic modulator (AOM) configured to perform mode-locking , the single pulse laser apparatus comprising:a photodiode configured to measure a laser beam oscillated in the resonator;a synchronizer configured to convert an electrical signal, which is generated by measuring the laser beam, into a transistor-transistor logic (TTL) signal;a delay unit configured to set a delay time for the TTL signal to synchronize the EOM and the AOM and output a trigger TTL signal according to the delay time;an AOM driver configured to input the trigger TTL signal to the AOM that performs mode-locking and drive the AOM; andan EOM driver configured to input the trigger TTL signal to the EOM that performs single pulse switching and drive the EOM,wherein:when the AOM performs Q-switching, the AOM performs mode-locking and performs the Q-switching by outputting energy stored due to ...

HIGH PULSE ENERGY AND HIGH BEAM QUALITY MINI LASER

A laser including a solid state laser gain medium having a D-shaped cross section and an unstable resonator laser cavity including the solid state laser gain medium configured with a geometric magnification in a range of 1 to 5 under the intended operating conditions, including the effects of thermal lensing in the gain medium. An optical switching device in the unstable resonator laser cavity generates a pulse duration in the range of 0.05 to 100 nanoseconds. A diode-pump source is configured to inject pump light through the curved or barrel surface of the D-shaped gain medium. 1. A laser comprising:a laser cavity configured as an unstable resonator with a geometric magnification in the range of 1 to 5 in at least one transverse plane;a solid state laser gain medium with a D-shaped cross section in the laser cavity; andan optical pumping source disposed to inject optical pump energy into the gain medium.2. The laser of in which the resonator cavity is configured as a non-confocal unstable resonator.3. The laser of in which the laser cavity is configured as a confocal or near-confocal unstable resonator.4. The laser of in which the solid state laser gain medium includes at least one Brewster-angled end face.5. The laser of in which the laser gain medium includes two Brewster-angled end faces.6. The laser of further including a passive or active optical switching device configured to generate a pulse duration in the range of 0.05-100 nanoseconds.7. The laser of in which the optical switching device is a Cr:YAG passive Q-switch.8. The laser of in which the optical switching device is an electro-optic Pockels cell configured as a Q-switch.9. The laser of in which the optical switching device is an electro-optic Pockels cell configured as a cavity dumper.10. The laser of in which the optical switching device is an acousto-optic Q-switch.11. The laser of in which the optical pumping source includes at least one laser diode configured to side pump the D-shaped laser rod. ...

SINGLE PULSE LASER APPARATUS

Provided is a single pulse laser apparatus. The apparatus including a resonator having a first mirror, a second mirror, a gain medium, and electro-optic modulators (EOMs) which perform each mode-locking and Q-switching, the apparatus includes a photodiode which measures laser light that oscillates from the resonator, a synchronizer which converts an electrical signal generated by measuring the laser light into a transistor-transistor logic (TTL) signal, a delay unit which sets a latency determined in order to synchronize a mode-locked pulse with a Q-switched pulse to the TTL signal, and outputs a trigger TTL signal according to the latency, and a Q-driver which inputs the trigger TTL signal to the EOM which performs Q-switching, and causes the EOM to operates. 1. A single pulse laser apparatus including a resonator having a first mirror , a second mirror , a gain medium , and electro-optic modulators (EOMs) configured to perform each mode-locking and Q-switching , the apparatus comprising:a photodiode configured to measure laser light that oscillates from the resonator;a synchronizer configured to convert an electrical signal generated by measuring the laser light into a transistor-transistor logic (TTL) signal;a delay unit configured to set a latency determined in order to synchronize a mode-locked pulse with a Q-switched pulse to the TTL signal, and output a trigger TTL signal according to the latency; anda Q-driver configured to input the trigger TTL signal to the EOM which performs Q-switching, and cause the EOM to operate.2. The apparatus of claim 1 , further comprising a controller configured to monitor a pulse width and pulse energy of laser light output from the resonator claim 1 , and determine the latency.3. The apparatus of claim 2 , wherein the controller determines a duration time in which the trigger TTL signal is continued.4. The apparatus of claim 1 , further comprising a power supply configured to supply energy to the gain medium claim 1 , and input ...

LASER DEVICE, MULTI-WAVELENGTH LASER DEVICE, AND PHOTOACOUSTIC MEASUREMENT APPARATUS

The laser device includes a laser crystal, a resonator including a pair of mirrors between which the laser crystal is interposed, a Q switch that is disposed on an optical path of the resonator and controls a Q value of the resonator, and a Brewster thin-film polarizer that is disposed on the optical path of the resonator and transmits selectively p-polarized light. The thin-film polarizer has wavelength selectivity in which a p-polarized light transmittance at a first wavelength exhibiting a maximum gain of the laser crystal is 5% or more to 25% or less, the p-polarized light transmittance monotonically increases as a wavelength becomes longer than the first wavelength, and a maximum transmittance is exhibited at a third wavelength. The laser device oscillates laser light at a second wavelength that is a wavelength longer than the first wavelength and shorter than or equal to the third wavelength. 1. A laser device comprising:a laser crystal;a resonator including a pair of mirrors between which the laser crystal is interposed;a Q switch that is disposed on an optical path of the resonator and controls a Q value of the resonator; anda Brewster thin-film polarizer that is disposed on the optical path of the resonator and transmits selectively p-polarized light,wherein the thin-film polarizer has wavelength selectivity in which a p-polarized light transmittance at a first wavelength exhibiting a maximum gain of the laser crystal is 5% or more to 25% or less, the p-polarized light transmittance monotonically increases as a wavelength becomes longer than the first wavelength, and a maximum transmittance is exhibited at a third wavelength, andwherein the laser device oscillates laser light at a second wavelength that is a wavelength longer than the first wavelength and shorter than or equal to the third wavelength and that has a p-polarized light transmittance of 90% or more in the thin-film polarizer.2. The laser device according to claim 1 ,wherein the p-polarized ...

PASSIVELY Q-SWITCHED LASER AND LASER SYSTEM FOR RANGING APPLICATIONS

A passively, Q-switched laser operating at an eye safe wavelength of between 1.2 and 1.4 microns is described. The laser may operate at a lasing wavelength of 1.34 microns and use a gain element of Nd:YVOand a saturable absorber element of V:YAG. The position of the resonator axial mode spectrum relative to a gain peak of the gain element is controlled to yield desired characteristics in the laser output. 1. A passively Q-switched laser configured to output a series of pulses at a lasing wavelength between 1.2 and 1.4 microns comprising:a gain element having a first and a second surface, the first surface having a highly reflective coating at the lasing wavelength between 1.2 and 1.4 microns to form a first end of the resonator;a saturable absorber element;a second end of the resonator formed by a second surface having a partially transmitting optical coating at the lasing wavelength between 1.2 and 1.4 microns; anda pump source having a pump beam directed to the first surface of the gain element; wherein an axial mode spectrum of a resonator formed between the first surface of the gain element and the second end of the resonator is controlled relative to a gain peak of the gain element.2. A passively Q-switched laser as recited in claim 1 , wherein a peak in the axial mode spectrum is aligned with the gain peak of the gain element.3. A passively Q-switched laser as recited in claim 2 , wherein the passively q-switched laser emits more than 90% of the pulses in the series of emitted pulses on a single axial mode.4. A passively Q-switched laser as recited in claim 1 , wherein two peaks in the axial mode spectrum straddle the gain peak of the gain element such that the gain peak is centered between the two peaks in the axial mode spectrum.5. A passively Q-switched laser as recited in claim 4 , wherein the passively Q-switched laser emits two axial modes with a first pulse operating on a first axial mode and a second pulse that immediately follows the first pulse ...

Q-switched Cavity Dumped Sub-nanosecond Laser

Apparatuses and methods are disclosed for applying laser energy having desired pulse characteristics, including a sufficiently short duration and/or a sufficiently high energy for the photomechanical treatment of skin pigmentations and pigmented lesions, both naturally-occurring (e.g., birthmarks), as well as artificial (e.g., tattoos). The laser energy may be generated with an apparatus having a resonator with a sub-nanosecond round trip time. 1. A laser oscillator for generating laser energy having a pulse duration of less than 1 nanosecond comprising:(a) a first mirror and a second mirror within a housing, with the first mirror and the second mirror providing a sub-nanosecond round trip time for laser radiation along an axis between the first mirror and the second mirror;(b) an electro-optic device, a polarizer and a lasing medium positioned between the first mirror and the second mirror along the axis; and(c) a pump source operatively coupled to the lasing medium,(d) wherein the laser oscillator is capable of proceeding through at least three consecutive states comprising hold-off, buildup and cavity dumping.2. The laser oscillator of claim 1 , wherein the cavity dumping state has a range of acceptable transient times that are greater than the ideal step function transient time.3. The laser oscillator of claim 1 , wherein the cavity dumping state has a range of acceptable transient times that are greater than the ideal step function transient time claim 1 , wherein a range of acceptable transient times includes from 0.5 round trip times to 5 round trip times which generates output pulse durations that range from 1 round trip time to 2.5 round trip times claim 1 , the round trip time being sub-nanosecond.4. The laser oscillator of claim 1 , wherein the first mirror and the second mirror are fixed within the housing to define a static resonator chamber having a sub-nanosecond round trip time.5. The laser oscillator of claim 1 , wherein the lasing medium comprises ...

Q-switched cavity dumped CO2 laser for material processing

This disclosure discusses techniques for obtaining wavelength selected simultaneously super pulsed Q-switched and cavity dumped laser pulses utilizing high optical damage threshold electro-optic modulators, maintaining a zero DC voltage bias on the CdTe electro-optic modulator (EOM) so as to minimize polarization variations depending on the location of the laser beam propagating through the CdSe EOM crystal, as well as the addition of one or more laser amplifiers in a compact package and the use of simultaneous gain switched, Q-switched and cavity dumped operation of CO 2 lasers for generating shorter pulses and higher peak power for the hole drilling, engraving and perforation applications.

Electromagnetically pumped alkali metal vapor cell system

An electromagnetic pumped alkali metal vapor cell system is provided. The system comprises a vapor cell and windings. The vapor cell contains alkali metal and a buffer. The windings are positioned around the vapor cell and are configured to create an electromagnet field in the vapor cell when an AC signal is applied to the windings. The electromagnetic field pumps unexcited alkali vapor into unionized D 1 and D 2 states.

METHOD FOR ASSEMBLING TWO STRUCTURES AND DEVICE OBTAINED BY THE METHOD. MICROLASER APPLICATIONS

LASER APPARATUS HAVING MULTIPLE-PASS ELECTRO-OPTIC MODULATORS

A laser apparatus includes at least one electro-optic (EO) medium through which a polarized laser beam passes for N times, forming a plurality of first-pass to Nth-pass beams, by reflecting the polarized laser beam from at least one reflection mirror, and a power supplier configured to alternately provide a 1/N of a half-wave (λ/2) or quarter-wave (λ/4) voltage and remove the voltage to the EO medium, λ being a wavelength of the polarized laser beam. The at least one EO medium is tilted at angle θ and/or angle di with respect to one of the plurality of first-pass to Nth-pass beams. The at least one EO medium comprises a M number of EO mediums, and the power supplier is configured to alternately provide a 1/M*N of a half-wave (λ/2) or quarter-wave (λ/4) voltage and remove the voltage to each of the M number of EO mediums. 1. A laser apparatus with a multi-pass configuration , comprising:an electro-optic (EO) medium through which a polarized laser beam passes;at least one reflection mirror configured to reflect the polarized laser beam so that the polarized laser beam passes through the EO medium for N times, forming a plurality of first-pass to Nth-pass beams, an optical axis of the EO medium being tilted with respect to at least one of the plurality of first-pass to Nth-pass beams; anda power supply configured to alternatingly provide a 1/N of a half-wave or quarter-wave voltage and remove the 1/N of the half-wave or quarter-wave voltage to the EO medium, λ being the wavelength of the polarized laser beam.2. The laser apparatus according to claim 1 , whereinthe optical axis of the EO medium is tilted at a first angle on a first plane and/or a second angle on a second plane with respect to the at least one of the plurality of first-pass to Nth-pass beams.3. The laser apparatus according to claim 1 , whereinone of the EO medium or the at least one reflection mirror is tilted in multiple directions.4. The laser apparatus according to claim 1 , whereinthe plurality of ...

CO2 laser with rapid power control and material processing device with CO2 laser

Laser annealing apparatus and laser annealing method

Pulse laser device

高活性化イオン濃度を有するレーザ材料およびマイクロレーザキャビティならびにそれらの製造方法

(57)【要約】 【課題】 高濃度の活性化イオン、より具体的には少な くとも２％以上の濃度でドープした活性レーザ材料、お よびそれからマイクロレーザ（マイクロレーザキャビテ ィ）およびその製造方法を提供する。 【解決手段】 基板上で液相エピタキシャル成長法によ り活性媒質を生成し、次いで基板を除去してマイクロレ ーザを製造する。マイクロレーザあるいはマイクロレー ザキャビティは、反射鏡を備える。キャビティは、ポン ピングビームを介して励起される。

Laser annealing device and laser annealing method

본 발명은, 아몰퍼스 실리콘막(5)에 레이저 광을 조사하여 어닐 처리하는 레이저 어닐 장치이며, 일정한 펄스 폭을 갖는 일정 파장의 제1 레이저 광 L 1 을 발생하는 제1 펄스 레이저(6)와, 상기 제1 레이저 광 L 1 보다도 펄스 폭 및 파장이 긴 제2 레이저 광 L 2 를 발생하는 제2 펄스 레이저(7)와, 상기 제1 레이저 광 L 1 과 상기 제2 레이저 광 L 2 를 동일한 광축에 합성하는 합성 수단(8)과, 상기 제1 및 제2 펄스 레이저(6, 7)에 작용하여 상기 제1 및 제2 레이저 광 L 1 , L 2 의 발생 타이밍을 제어하는 제어 수단(3)을 구비하고, 상기 제어 수단(3)은 상기 제1 레이저 광 L 1 이 상기 제2 레이저 광 L 2 의 펄스 폭 내의 미리 정해진 타이밍에서 발생하도록 상기 제1 펄스 레이저(6)를 제어하는 것이다.

Short pulse laser system

A laser system which generates short duration pulses, such as under five nanoseconds at an energy level of up to a few milli-Joules per pulse (mJ/p) with near diffraction limited beam quality. A laser crystal is pumped (excited) by diode lasers. A resonator having at least two mirror surfaces defines a beam path passing through the laser crystal. The beam path in the resonator is periodically blocked by a first optical shutter permitting pump energy to build up in the laser crystal, except for a short period near the end of each pumping period. While the first optical shutter is open a second optical shutter blocks the light in the resonator except for periodic short intervals, the intervals being spaced such that at least one light pulse traveling at the speed of light in the resonator is able to make a plurality of transits through the resonator, increasing in intensity by extracting energy from the excited laser crystal on each transit. After the light pulse has built up in intensity, an optical release mechanism releases the pulse from resonator.

Short-pulse laser system

(57)【要約】 【課題】 必要十分なエネルギーで短パルスのレーザビ ームを発生させるレーザシステムを提供する。 【解決手段】レーザクリスタルがダイオードレーザによ り励起され、少なくとも２つの鏡面を有する共振器によ り光路が定義される。共振器内の光路は、ポンプ周期の 最後に近い短期間を除いて、第１の光学シャッタにより 周期的に遮断され、レーザクリスタル内にポンプエネル ギーが蓄積される。第１の光学シャッタが開いている 間、周期的な所定期間を除いて、第２の光学シャッタが 共振器内の光を遮断する。この期間は、光パルスが共振 器内を光速で複数回通過し、通過毎に励起されたレーザ クリスタルからエネルギーを抽出することで強度を高め るように設定されている。強化された光パルスは、光学 解放機構により共振器から解放される。

Multi-pulse regenerative amplified laser system

本发明提供了一种多脉冲再生放大的激光器系统，包括：种子源、脉冲选择器、多脉冲再生放大模块、控制器；其中：种子源，用于产生种子光脉冲序列；脉冲选择器，用于在控制器的控制下，从种子光脉冲序列中可控地选择1个或N个种子光脉冲，N≥2；多脉冲再生放大模块，用于对脉冲选择器所选择的1个或多个种子光脉冲进行再生放大。本发明通过设计多脉冲选择器，改进再生放大谐振腔，解决了以往的再生放大器激光器系统中仅导入一个种子光脉冲放大的问题，能够实现高重复频率多脉冲串输出，极大地提升了输出激光的能量。

Single-frequency laser peening method

단일 주파수의 출력 펄스를 얻는 레이저 동작 방법은 레이저 공진기에 펌프 소스로부터 발생되는 에너지가 이득 매질에 축적되는 시간 동안 발진을 방지하는 양의 캐비티내 손실을 유도하는 것을 포함하여 구성된다. 상기 공진기 내에 단일 주파수의 이완 발진 펄스가 형성될 때까지 펌프 소스로부터 발생되는 에너지로 이득 매질에 이득이 누적된다. 이완 발진 펄스의 개시를 감지하면 Q-스위칭 등에 의해 상기 캐비티내 손실이 감소되어 이득 매질에 축적된 누적 이득이 단일 주파수의 출력 펄스의 형태로 공진기로부터 출력된다. 전자적으로 제어가능한 출력 결합기를 제어하여 출력 펄스 특성을 변화시킨다. 상기 레이저는 마스터 오실레이터 전력 증폭기 구조에서 마스터 오실레이터로서 작용한다. 상기 레이저는 레이저 피닝에 사용된다.

Satellite-borne high-energy dual-wavelength all-solid-state pulse laser

本发明提供一种星载大能量双波长全固体脉冲激光器，包括依次主动调Q振荡器、预功率放大器、主功率放大器和倍频模块，主动调Q振荡器为U型谐振腔，包括第一保罗棱镜、第一光楔、第一波片、板条晶体、第一偏振分光棱镜、第二偏振分光棱镜、电光Q开关、第二波片、第二光楔、第二保罗棱镜和设置在板条晶体上的泵浦二极管阵列，预功率放大器、主功率放大器均包含光束整形镜组。本发明可以实现大能量高稳定高可靠性的脉冲激光输出，减小激光器的体积和重量，适用于多平台应用，尤其是星载平台，可作为星载气溶胶探测激光雷达、星载测距激光雷达等探测光源。

Controlling laser polarization

레이저 편광 제어 장치는 액정 가변 지연기와 같은 편광 변형 디바이스(24) 및 제어기(18)를 포함한다. 상기 편광 변형 디바이스는 레이저 빔(12)을 받아들여 그 빔의 편광을 변형시킨다. 상기 제어기는 그 레이저 빔에 의해 가공대상 구조물의 배열에 근거하여 레이저 빔의 편광의 변형을 제어하고자, 상기 편광 변형 디바이스로의 입력을 조정한다. 상기 편광 변형 디바이스는, 상기 편광 변형 디바이스에 의해 받아들여질 레이저 빔을 생성하고 변형된 레이저 빔을 그 레이저 빔에 의해 가공대상 구조물을 포함하는 워크피스 상에 집속하는 레이저 가공 시스템내로 통합되도록 되어 있다. The laser polarization control device includes a polarization modifying device 24 and a controller 18 such as a liquid crystal variable retarder. The polarization modifying device accepts a laser beam 12 to modify the polarization of the beam. The controller adjusts the input to the polarization modifying device to control the deformation of the polarization of the laser beam based on the arrangement of the workpiece to be processed by the laser beam. The polarization modifying device is adapted to be integrated into a laser processing system that generates a laser beam to be received by the polarization modifying device and focuses the modified laser beam on the workpiece including the structure to be processed by the laser beam.

Q-switching laser device

Dual-wavelength laser cross frequency hopping and frequency modulation Q output laser and laser output method

本发明公开了一种双波长激光交叉跳频调Q输出激光器及激光输出方法，其特征在于，所述激光器包括第二泵浦源、第二光纤、第二耦合透镜组、第二激光全反射镜、第二激光增益介质、第二起偏器、四分之一波片、第二45°反射镜、第二激光输出镜、电光调Q晶体、第一激光输出镜、第一45°反射镜、第一起偏器、第一激光增益介质、第一激光全反射镜、第一耦合透镜组、第一光纤和第一泵浦源。本发明通过随时间变化跳跃式地对两激光增益介质进行脉冲泵浦，实现双波长激光交叉跳频调Q输出。

Drive laser for EUV light source

Devices and methods for generating EUV light are disclosed. The device comprises an oscillator having an oscillator cavity length, L o , and defining an oscillator path and a multi-pass optical amplifier coupled with the oscillator to establish a combined optical cavity including the oscillator path, the combined cavity having a length, L combined , where L combined =(N+x)*L o , where “N” is an integer and “x” is a number between 0.4 and 0.6. The amplifier comprises a polarization discriminating optic inputting light traveling along a first beam path from the oscillator and having substantially a first linear polarization into the amplifier and outputting light having substantially a linear polarization orthogonal to the first polarization out of the amplifier along a second beam path.

Drive laser for EUV light source

A device is described herein which may comprise an oscillator having an oscillator cavity length, L o , and defining an oscillator path; and a multi-pass optical amplifier coupled with the oscillator to establish a combined optical cavity including the oscillator path, the combined cavity having a length, L combined , where L combined =(N+x)*L o , where “N” is an integer and “x” is a number between 0.4 and 0.6.

Drive laser for EUV light source

A device is described herein which may comprise an oscillator having an oscillator cavity length, L o , and defining an oscillator path; and a multi-pass optical amplifier coupled with the oscillator to establish a combined optical cavity including the oscillator path, the combined cavity having a length, L combined , where L combined =(N+x)*L o , where “N” is an integer and “x” is a number between 0.4 and 0.6.

Drive laser for EUV light source

A device comprising a laser source producing a continuous output on a beam path and an amplifier is disclosed. The device further includes a partially transmissive, partially reflective optic disposed on said beam path between said laser source and said amplifier. The device further includes a droplet generator positioned to deliver a droplet moving on a path intersecting said beam path, the droplet reflecting light to establish an optical cavity with said optic.

Drive laser for EUV light source

A device is described herein which may comprise an oscillator having an oscillator cavity length, L 0 , and defining an oscillator path; and a multi-pass optical amplifier coupled with the oscillator to establish a combined optical cavity including the oscillator path, the combined cavity having a length, L combined , where L combined =(N+x)*L 0 , where “N” is an integer and “x” is a number between 0.4 and 0.6.

Passive Q-switched solid laser

本发明涉及被动调Q固体激光器，其包括：谐振器，在其中布置有主动激光材料，并且所述谐振器具有用于将具有小于1ns的脉冲持续时间的激光脉冲从谐振器中耦合输出的耦合输出端面镜；光导纤维，从耦合输出端面镜耦合输出的激光脉冲被耦合输入到所述光导纤维中；和啁啾体布拉格光栅，激光脉冲在其穿过光导纤维之后在所述啁啾体布拉格光栅上反射。在啁啾体布拉格光栅上反射之后的脉冲持续时间小于30ps。布置在谐振器中的主动激光材料是Nd:YAG，并且在谐振器中还布置有由Cr:YAG形成的可饱和的吸收体，其具有在不饱和的状态中为小于50%的透射率。谐振器的长度在1mm至10mm的范围中，并且在耦合输出端面镜上耦合输出的激光脉冲具有在1μJ至200μJ的范围中的脉冲能量。

Short pulse laser system with switchable polarization

本申请提供的一种偏振可切换的短脉冲激光系统，属于激光器技术领域，包括：激光振荡模块、激光放大模块和激光倍频偏振切换模块，所述激光放大模块的光输入端连接所述激光振荡模块，所述激光放大模块的光输出端连接所述激光倍频偏振切换模块，所述激光振荡模块用于产生波长为1064 nm的纳秒脉冲激光，所述激光放大模块用于纳秒脉冲激光的能量放大，所述激光倍频偏振切换模块输出双波长偏振态可切换的激光。本申请提供的偏振可切换的短脉冲激光系统，更加适用于激光测距、光电对抗、大气探测等领域对激光器的更高要求。

High repetition frequency large energy nanosecond pulse laser and use method thereof

本发明公开了一种高重频大能量纳秒级脉冲激光器及其使用方法,包括：泵浦激光器、激光增益池、非稳定谐振腔和电光调Q装置。泵浦激光器输出的泵浦激光光束从激光增益池的增益介质端面泵浦，透射至激光增益介质内，向所述谐振腔提供能量；激光在由凹面反射镜、凸面反射镜和刮刀镜组成的非稳定谐振腔中振荡，并通过电光调Q装置进行脉冲调制，最后脉冲激光从刮刀镜输出。本发明提供了一种单腔振荡实现高重频(≥200Hz)、大能量(≥20J)、窄脉宽的激光器。该激光器将具有效率高、结构简单、可放大性好、使用可靠、环境适应能力较强等特点。可以被广泛地使用在工业加工，特别是熔覆冲击强化领域。

A kind of double half anti-gauss hollow Q-switched lasers of the adjustable polarization based on electro-optic crystal

本发明公开了一种基于电光晶体的可调偏振双半反高斯空心调Q激光器，包括从左至右依次设置的泵浦源(1)、耦合光学系统(2)、激光增益介质(3)、电光晶体圆锥镜(5)和玻璃圆锥镜(6)，所述电光晶体圆锥镜(5)的上方设置有正电极(7)，电光晶体圆锥镜(5)的下方设置有负电极(4)；所述激光增益介质(3)的左端面作为激光器谐振腔输入镜，玻璃圆锥镜(6)作为谐振腔的输出镜，激光增益介质(3)的左端面与玻璃圆锥镜(6)的负圆锥镜面构成激光谐振腔。本发明能够实现空心激光器的调Q，以及两个正交偏振态的双半反高斯空心激光束交替输出。

Q-switched cavity dumped CO2 laser for material processing

This disclosure discusses techniques for obtaining wavelength selected simultaneously super pulsed Q-switched and cavity dumped laser pulses utilizing high optical damage threshold electro-optic modulators, maintaining a zero DC voltage bias on the CdTe electro-optic modulator (EOM) so as to minimize polarization variations depending on the location of the laser beam propagating through the CdSe EOM crystal, as well as the addition of one or more laser amplifiers in a compact package and the use of simultaneous gain switched, Q-switched and cavity dumped operation of CO 2 lasers for generating shorter pulses and higher peak power for the hole drilling, engraving and perforation applications.

Short pulse laser equipment

Q-switched, cavity dumped laser systems for material processing

This disclosure discusses techniques for obtaining wavelength selected simultaneously super pulsed Q-switched and cavity dumped laser pulses utilizing high optical damage threshold electro-optic modulators, maintaining a zero DC voltage bias on the CdTe electro-optic modulator (EOM) so as to minimize polarization variations depending on the location of the laser beam propagating through the CdSe EOM crystal, as well as the addition of one or more laser amplifiers in a compact package and the use of simultaneous gain switched, Q-switched and cavity dumped operation of CO 2 lasers for generating shorter pulses and higher peak power for the hole drilling, engraving and perforation applications.

Q-switched cavity dumped co2 laser for material processing

This disclosure discusses techniques for obtaining wavelength selected simultaneously super pulsed Q-switched and cavity dumped laser pulses utilizing high optical damage threshold electro-optic modulators, maintaining a zero DC voltage bias on the CdTe electro-optic modulator (142) (EOM) so as to minimize polarization variations depending on the location of the laser beam (402) propagating through the CdSe EOM crystal (142), as well as the addition of one or more laser amplifiers in a compact package and the use of simultaneous gain switched, Q-switched and cavity dumped operation of CO2 lasers for generating shorter pulses and higher peak power for the hole drilling, engraving and perforation applications.

Q-switched CO2 laser for material processing

A simultaneously super pulsed Q-switched CO 2 laser system for material processing is disclosed. The system comprises sealed-off folded waveguides with folded mirrors that are thin film coated to select the output wavelength of the laser. The system also comprises a plurality of reflective devices defining a cavity; a gain medium positioned within the cavity for generating a laser beam; a cavity loss modulator for modulating the laser beam, generating thereby one or more laser pulses; a pulsed signal generation system connected to the cavity loss modulator for delivering pulsed signals to the cavity loss modulator thereby controlling the state of optical loss within the cavity; a control unit connected to the pulsed signal generation system for controlling the pulsed signal generation system; and a pulse clipping circuit receptive of a portion of the laser beam and connected to the pulsed signal generation system for truncating a part of the laser pulses.

Q-switched, cavity dumped laser systems for material processing

This disclosure discusses techniques for obtaining wavelength selected simultaneously super pulsed Q-switched and cavity dumped laser pulses utilizing high optical damage threshold electro-optic modulators, maintaining a zero DC voltage bias on the CdTe electro-optic modulator (EOM) so as to minimize polarization variations depending on the location of the laser beam propagating through the CdSe EOM crystal, as well as the addition of one or more laser amplifiers in a compact package and the use of simultaneous gain switched, Q-switched and cavity dumped operation of CO 2 lasers for generating shorter pulses and higher peak power for the hole drilling, engraving and perforation applications.

Pulsed CO2 laser including an optical damage resistant electro-optical switching arrangement

A laser includes a gain medium located in a laser resonator. The gain medium generates plane polarized radiation plane polarized in a first polarization orientation. An electro-optical switch is located in the resonator. When the switch is activated the polarization plane of the laser radiation is rotated to a second orientation after making a forward and a reverse pass through the optical switch. When the switch is deactivated, the polarization orientation of the forward and reverse transmitted laser radiation remains about the same. A polarization selective device is located in the resonator between the electro-optical switch and the gain medium. The polarization selective device is arranged to permit circulation in the resonator of laser radiation in the first polarization orientation, and to restrict circulation of laser radiation in the second polarization orientation. The Gain medium is energized and the switch activated to allow energy to build in the gain medium. The switch is then deactivated to allow laser radiation to circulate in the resonator and deliver a laser pulse. A method of activating the switch by a sequence of DC pulses is disclosed.

Electro-optical modulator module for CO2 laser Q-switching, mode-locking, and cavity dumping

Various electro-optical modulator module designs are presented, which can provide for uniform, symmetric, and efficient heat removal for mode-locking, Q-switching, and/or cavity dumping operations. Heat can be uniformly extracted from an EO crystal without imposing undue stress, thereby preventing birefringence and laser beam degradation. A liquid-cooling approach can be used for high-duty operations, such as mode-locking operations. Efficient heat removal can prevent thermal run-away from electrical heating of the crystal due to the large drop in the electrical resistance of CdTe with increasing temperature when operated above 50° C. RF or video arcing and subsequent damage to the EO crystal can be prevented by surrounding the crystal with a low dielectric constant material that lowers the capacitance coupling to ground, while still maintaining good thermal cooling.

Injection locking Q-switched and Q-switched cavity dumped CO2 lasers for extreme UV generation

A CO 2 laser reference oscillator (RO) can provide injection seeding to a Q-switched (QS) or Q-switched cavity dumped (QSCD) CO 2 laser, where the output frequency of the RO laser is locked to the peak of the laser line by the use of appropriate electronics to dither one of the resonator mirrors of the reference oscillator. This injected radiation seeds the radiation building up within the Q-switched laser cavity, such that the oscillating frequency favors the wavelength of the injected radiation. An electronic feedback control circuit can be used to lock an axial mode of the Q-switched laser to line center. The change in build-up time of the pulses within the QS laser can be used to maintain cavity length at a value that enables oscillating at the peak of the same laser line that is injected into QS laser.

High damage threshold Q-switched CO2 laser

A thin film polarizer (TFP) and a half-wave CdTe electro-optical crystal are utilized to achieve a higher damage threshold in Q-switching CO 2 lasers for material processing applications. Half-wave CdTe electro-optical modulators can be used without the arcing and corona problems typically associated with the higher drive voltage by placing low dielectric constant insulators (such as BeO) around the CdTe crystal. Doubling the voltage placed across a CdTe crystal enables the crystal to function as a half-wave phase retarder EO switch with the same dimensions as a crystal functioning as a quarter-wave EO modulator. These half-wave EO switches can be used with TFPs to shape the output pulses, as well as to direct alternate pulses of repetitively pulsed super pulsed slab lasers to alternate scanners, thereby doubling the output of laser hole drilling systems.

Actively Q-switched laser system using quasi-phase-matched electro-optic Q-switch

A Q-switched laser system is disclosed. The laser system employs a quasi-phase-matched electro-optic (QPM EO) crystal as the laser Q-switch. When applied with a certain modulating electric field, the QPM EO crystal can function as a polarization rotator to rotate the polarization direction of the resonant laser beam in a polarization-dependent laser resonator, thereby switching the laser resonator between high-loss and low-loss cavity states to achieve laser Q-switching. Compared with traditional electro-optic Q-switched laser system, the disclosed laser system is characterized by a low switching-voltage, reduced cost, and compactness. A quasi-phase-matched electro-optically Q-switched wavelength-conversion and wavelength-tunable laser system is also disclosed. The disclosed laser system integrates a QPM electro-optic Q-switch and a QPM nonlinear wavelength converter in a single crystal substrate to perform a high-efficiency intracavity wavelength conversion. The disclosed laser system is therefore simple and compact and has lower system requirements on wall-plug power and higher overall conversion efficiency.

CO2 laser with fast power control

Gegenstand der Erfindung ist ein CO2-Laser, der eine schnelle Leistungsmodulation, insbesondere eine hocheffiziente Güteschaltung ermöglicht. Kerngedanke ist dabei die Unterteilung des Resonators in einen Hochleistungszweig, der u. a. das aktive Medium (1) enthält, sowie einen Niederleistungs-Rückkoppelzweig (14), in dem die leistungsempfindlichen Elemente zur Strahlformung, insbesondere die Modulatoren, angeordnet sind. Ermöglicht wird dies durch eine geeignete Anordnung eines Polarisationsstrahlteilers (5) und eines λ/4-Phasenschiebers (2). Die freie Einstellbarkeit eines Winkels φ zwischen diesen beiden Bauelementen gestattet die außerordentlich flexible Realisierung verschiedener Betriebsarten, insbesondere die Optimierung des Rückkoppelgrades bei der Impulserzeugung. The subject matter of the invention is a CO2 laser which enables a fast power modulation, in particular a high-efficiency Q-switching. Core idea is the subdivision of the resonator in a high-performance branch, the u. a. contains the active medium (1), and a low-power feedback branch (14), in which the power-sensitive elements for beam shaping, in particular the modulators, are arranged. This is made possible by a suitable arrangement of a polarization beam splitter (5) and a λ / 4-phase shifter (2). The free adjustability of an angle φ between these two components allows the extremely flexible realization of different operating modes, in particular the optimization of the feedback in the pulse generation.

Laser machining apparatus and laser machining method

Method for operating a laser system

Single pulse laser apparatus

A single pulse laser apparatus comprises: a first mirror and a second mirror disposed at both ends and having a reflectance of a predetermined level or higher; a gain medium which is rotated at a predetermined angle to oscillate a laser beam in a passive mode locking state; a linear polarizer for outputting light having a specific polarization in the oscillated laser beam; an etalon for adjusting the pulse width of the oscillated laser light; and an electro-optic modulator which performs Q-switching and single pulse switching. It is possible to perform mode locking.

Q-switched cavity dumped sub-nanosecond laser

Apparatuses and methods are disclosed for applying laser energy having desired pulse characteristics, including a sufficiently short duration and/or a sufficiently high energy for the photomechanical treatment of skin pigmentations and pigmented lesions, both naturally-occurring (e.g., birthmarks), as well as artificial (e.g., tattoos). The laser energy may be generated with an apparatus having a resonator with a sub-nanosecond round trip time.

Passively cavity-dumped laser apparatus, system and methods

Systems and methods for employing an electro-optic and photoconductive optical element operating in combination with a polarizer and 100% reflective mirrors to passively control dumping of power from a resonator. The optical element may be constructed of electro-optic material (e.g., Bismuth Silicon Oxide (BSO), Bismuth Germanium Oxide (BGO)), the refractive index of which may be altered by the application of an externally applied electric field. The presence of incident light changes the photoconductivity of the optical element and, therefore, also changes the polarization state of the light passing through the optical element. When combined with a conventional polarizer, the device acts as a self-triggering optical valve to suddenly divert the path of light within a laser to outside of the normal resonator path. Optical power that has been stored inside the laser resonator is then dumped out of the laser in a single, very-high power pulse.

Laser with combined q-switch and synchronized cavity dump circuit

A laser employing a single modulator in the form of a Pockels cell in the laser cavity and a polarizer. The polarizer in the cavity passes radiation having one polarization direction coming from one direction and diverts radiation having another polarization direction into an absorber. The polarizer passes radiation having one polarization direction coming from an opposite direction and diverts radiation having the other polarization direction into an output path. The modulator in the cavity rotates the polarization direction of radiation to establish the other polarization direction when energized and permits passage of radiation when it is deenergized. A high voltage electrical waveform generator circuit is provided which generates a voltage waveform having a positive DC voltage leading edge and a negative DC voltage trailing edge to the modulator. A gas trigger tube is provided in the circuit which generates a positive DC voltage leading edge in its plate circuit when it is independently triggered by a trigger signal. Another gas trigger tube generates a positive voltage when it is triggered by another trigger signal from a photodiode positioned to intercept radiation leaking from laser cavity. A coupling circuit which couples the plate circuits of the trigger tubes includes a capacitor which converts the positive voltage generated by the other trigger tube into the negative DC voltage trailing edge of the voltage waveform. The coupling circuit may also include a differentiator which allows the voltage levels on the trigger tube plates to be independently varied without affecting each other.

Method and apparatus for producing isolated laser pulses having a fast rise time

Disclosed herein is a laser oscillator system which provides laser pulses having a characteristically short rise time and high energy content. A laser oscillator is Q-switched to produce short duration pulses of radiation and a small amount of each pulse is tapped off to trigger a spark gap discharge in an electro-optic modulator. A pair of polarizing elements and the modulator are located along the axis of the optical cavity in the oscillator. With selective activation of the modulator, the polarizer elements interrupt the resonant reflections of the optical flux between the mirrors defining the oscillator and the Q-switched pulse energy is rapidly dumped from the cavity as fast rise time pulses.

Method for cavity dumping a Q-switched laser

A method for cavity dumping a Q-switched laser having a gaseous gain medium to obtain submicrosecond output pulses, typically controllably variable between ten and three hundred nanoseconds at a high pulse repetition frequency typically up to at least twenty-five thousand pulses per second is disclosed. In a laser adapted for continuous wave operation, a combination of a retardation element and an electrooptic modulator provides a first polarization state to intracavity radiation incident onto an intracavity polarization coupler oriented to couple out of the cavity radiation having the first polarization state to provide a high loss condition to the cavity to maintain the laser below threshold. A voltage applied quickly to the modulator converts the first polarization state to a second polarization state to provide a low loss condition to the cavity to Q-switch the laser. Terminating the voltage near the maximum Q-switch buildup converts the polarization to the first polarization state which is cavity dumped by the polarization coupler to provide an output pulse. Controlling the fall time of the voltage termination controls the pulse width of the output pulse while controlling the duration of the voltage controls the energy of the output pulse.

Driver unit for a laser Q-switch

A Q-switch driver for controlling laser output pulses, so that the laser output pulses are of an approximately equal amplitude. Sequences of light request pulses, each such light request pulse for causing the laser to produce a laser output pulse, are input to the Q-switch driver. The Q-switch is controlled by an RF oscillating signal produced by the Q-switch driver such that when the RF signal is present there is no output signal from the laser, and when the RF signal is zero a laser output pulse is produced. If the time between sequences of light request pulses is greater than a predetermined value, the RF signal from the Q-switch driver is modified by leaving the RF partially on so that there is some Q-spoiling present. The amount of RF produced during each light request pulse is gradually diminished exponentially over a predetermined time so that eventually the RF goes to zero during each light request pulse. Modifying the RF produced by the Q-switch driver prevents the generation of a giant first pulse by the laser.