Abstract: A light source device is provided with a coherent light source for emitting the coherent light, and a pattern changer for changing an interference pattern of the coherent light on a surface of the illumination object. The pattern changer includes a photorefractive crystal which is arranged between the coherent light source and the illumination object and on an optical path of the coherent light and exhibits a photorefractive effect, and a changer for changing at least one of a light intensity distribution, a polarization direction, a wavelength and an intensity of coherent light incident on the photorefractive crystal. The illumination object is illuminated with the coherent light.

Abstract: The present invention relates to a polarized light emitting diode (LED) device and the method for manufacturing the same, in which the LED device comprises: a base, a light emitting diode (LED) chip, a polarizing waveguide and a packaging material. In an exemplary embodiment, the LED chip is disposed on the base and is configured with a first light-emitting surface for outputting light therefrom; and the waveguide, being comprised of a polarization layer, a reflection layer, a conversion layer and a light transmitting layer, is disposed at the optical path of the light emitted from the LED chip; and the packaging material is used for packaging the waveguide, the LED chip and the base into a package.

Abstract: The invention relates to a precision optical frequency tunable laser. The laser includes: a laser gain medium, an intracavity collimating lens, an active optical phase modulator, a tunable acousto-optic filter and an intracavity total reflection mirror all arranged sequentially in a laser cavity, and the tunable laser further includes an active polarization rotator, a polarization beam splitter, two etalons, a temperature control system attached to the etalons, two total reflection mirrors, a radio frequency signal source, a laser pumping source, an active optical phase modulator drive source, an active polarization rotator drive source and a laser drive control circuit. Through the temperature control system attached to the etalons, stable laser output and the precision optical frequency tuning less than 1 GHz within a wide spectrum range can be realized, thereby greatly reducing the bandwidth requirements in achieving narrowband filtering for the tunable acousto-optic filter.

Abstract: An extreme ultraviolet light generation system used with a laser apparatus may be provided, and the extreme ultraviolet light generation system may include: a chamber including at least one window for at least one laser beam and a target supply unit for supplying a target material into the chamber; and at least one polarization control unit, provided on a laser beam path, for controlling a polarization state of the at least one laser beam.

Abstract: The present invention relates to an apparatus for generating an ultra-short ultra-high intensity pulse laser, comprising: a pulse laser providing unit which generates an ultra-short ultra-high intensity pulse laser, stretches pulse width, then selects and provides only a pulse laser having a predetermined polarizing angle; a polarization characteristic adjusting unit which divides the pulse laser provided by the pulse laser providing unit into S-polarizing component light and P-polarizing component light, varies the phase difference and amplitude difference between the S-polarizing component light and the P-polarizing component light, and combines the two types of light to generate a pulse laser with varied polarization characteristics; and a pulse compression unit which compresses the pulse width of the pulse laser, the polarization characteristics of which are varied by the polarization characteristic adjusting unit, and outputs the pulse laser.

Abstract: An optical transmitter includes a laser configured to emit light, a power of the light increasing with temperature decreasing, a Faraday rotator configured to rotate a polarization direction of the light in accordance with the temperature, and a first polarizer that has a principal axis inclined at a given angle and inputs the light output from the Faraday rotator.

Abstract: An electro-optic waveguide polarization modulator includes cladding layers, and a waveguide core sandwiched between the cladding layers, wherein the waveguide core has a higher refractive index than the cladding layers. The modulator further includes primary electrodes arranged on the opposite side of one cladding layer to the core and a secondary electrode arranged on the opposite side of another cladding layer to the core. The electrodes are arranged to provide an electric field having field components in perpendicular directions within the waveguide core so as to modulate the refractive index such that electromagnetic radiation propagating through the core is converted from a first polarization state to a second polarization state. The modulator further includes a grading layer sandwiched between the cladding layers and the core, the grading layer having an effective refractive index intermediate between that of the waveguide core and the cladding layer.

Abstract: An optical amplifier receives a seed laser having a wavelength of 1064 nm. Amplification occurs in a segmented Nd:YVO4 gain medium pumped with a pump source. Each segment of the gain medium has a length and dopant concentration and together the segments enhance power absorption in the gain medium enabling use of a higher power end pump which increases pulse energy and average power of the laser. The first end of the gain medium includes a wedge surface which arranges a quad-pass optical amplifier to achieve high extraction efficiency.

Abstract: A degree of polarization control device includes: a calcium fluoride crystal substrate for transmitting a laser beam; a polarization monitor for measuring the degree of polarization of a laser beam transmitted through the calcium fluoride crystal substrate; and a controller for controlling the rotation angle of the calcium fluoride crystal substrate according to the degree of polarization measured by the polarization monitor; the calcium fluoride crystal substrate being formed by a flat plate having a laser beam entering surface and a laser beam exiting surface running in parallel with the (111) crystal face, the Brewster angle being selected for the incident angle, the rotation angle around the [111] axis operating as a central axis being controlled by the controller.

Abstract: A vertical-cavity surface-emitting laser array includes a substrate having an element forming area, multiple columnar structures formed in the element forming area on the substrate, and at least one metal wire formed adjacent to the multiple columnar structures. Each columnar structure includes a lower semiconductor reflector of a first conductivity type, an upper semiconductor reflector of a second conductivity type, and an active region formed between the lower semiconductor reflector and the upper semiconductor reflector. The columnar structure emits light in a direction perpendicular to the substrate. The at least one metal wire has a distortion applying segment that extends in the same direction relative to the multiple columnar structures.

Abstract: A patterned retarder is described that may be used with a laser source array to obtain a combined beam suitable for three-dimensional laser image projection using orthogonal polarization states and/or orthogonal color spaces.

Abstract: Materials, methods, structures and device including the same can provide a semiconductor device such as an LED using an active region corresponding to a non-polar face or surface of III-V semiconductor crystalline material. In some embodiments, an active diode region contains more non-polar III-V material oriented to a non-polar plane than III-V material oriented to a polar plane. In other embodiments, a bottom region contains more non-polar m-plane or a-plane surface area GaN than polar c-plane surface area GaN facing an active region.

Abstract: In a frequency-tripled fiber-MOPA, a pre-amplified plane-polarized seed-pulse having a fundamental frequency is divided into two pulse-components, plane-polarized in polarization-orientations at 90-degrees to each other. The fundamental-wavelength pulse-components are amplified in a common amplifier-fiber. The amplified components are separately propagated on different optical paths. One of the amplified components is frequency-doubled. The frequency-doubled component on one path and fundamental-frequency component on the other path are then combined on a common-path and sum-frequency mixed to provide a frequency-tripled pulse.

Abstract: laser devices described may emit a beam of electromagnetic radiation having a large wavelength (e.g., mid-infrared, far-infrared) and exhibiting a low angle of divergence. In some embodiments, the wavelength of the electromagnetic radiation is between 3 microns and 500 microns and the divergence angel is less than 15 degrees. Electromagnetic waves may be produced from a single monolithic laser device which includes a laser waveguide (e.g., quantum cascade laser waveguide) and a collimating element having at least one indented region (e.g., a plurality of periodically disposed grooved structures). A portion of the electromagnetic radiation may propagate as surface waves (e.g., surface plasmons) along the surface of the collimating element where indented regions in the collimating element may decrease the propagation velocity of the surface waves. A portion of the electromagnetic radiation may also be substantially convinced within a grooved structure of the collimating element (e.g., as channel polaritons).

Abstract: A laser anti-reflection device includes a polarizing beam splitter, a ?/4 wave plate and an absorber disposed in an outgoing light path of a laser emitting linearly polarized light with a wavelength of ?. The linearly polarized light from the laser passes through the polarizing beam splitter and the ?/4 wave plate in turn to become a circularly polarized light beam. Part of the circularly polarized light beam is then reflected by a workpiece to be processed along the original light path and passes the ?/4 wave plate to become a linearly polarized light beam with a polarization direction vertical to that of the outgoing linearly polarized light beam. The vertical polarized beam passes the polarizing beam splitter, deviates from the light path of the outgoing linearly polarized light beam and reaches the absorber. The laser anti-reflection device prevents reflected light from damaging the laser from high power lasers.

Abstract: An optical device may include: an optical module disposed in a beam delivery path of a laser beam; a beam adjusting unit disposed in the beam delivery path for adjusting the beam delivery path of the laser beam; a measuring unit disposed in the beam delivery path for detecting the beam delivery path; and a control unit for controlling the beam adjusting unit based on a detection result of the beam delivery path of the laser beam detected by the measuring unit.

Abstract: A gas discharge chamber that uses a calcium fluoride crystal which reduces a breakage due to mechanical stress (window holder and laser gas pressure), thermal stress from light absorption, and the like, increases the degree of linear polarization of output laser, and suppresses degradation due to strong ultraviolet (ArF, in particular) laser light irradiation. A first window (2) and a second window (3) of the gas discharge chamber have an incident plane and an emitting plane in parallel with a (111) crystal plane of their calcium fluoride crystal. With respect to an arrangement where laser light entering the calcium fluoride crystal passes through a plane including a <111> axis and a <001> axis of each of the first window (2) and the second window (3) as seen from inside the chamber (1), the first window (2) and the second window (3) are arranged in positions rotated in the same direction by the same angle about their <111> axis.

Abstract: In the case of a lens array type homogenizer optical system, the incident angle and intensity of a laser beam 1 entering a large-sized lens (long-axis condenser lens 22) of a long-axis condensing optical system, which is provided on the rear side, are changed for every shot by performing laser irradiation while long-axis lens arrays 20a and 20b are reciprocated in a direction corresponding to a long axial direction of a linear beam (X-direction). Therefore, vertical stripes are significantly reduced. Further, the incident angle and intensity of a laser beam 1 entering a large-sized lens (projection lens 30) of a short-axis condensing optical system, which is provided on the rear side, are changed for every shot by performing laser irradiation while short-axis lens arrays 26a and 26b are reciprocated in a direction corresponding to a short axial direction of a linear beam (Y-direction). Therefore, horizontal stripes are significantly reduced.

Abstract: A laser apparatus for generating extreme ultraviolet (EUV) light at a wavelength of approximately 13 nm is provided. The laser apparatus may be combined with a reduced projection reflective optical system. Systems and methods for generating EUV light are also provided.

Abstract: In at least one embodiment a laser system includes a fiber laser source, a polarization controller and a wavelength converter. The relative power distribution between a pump wavelength and a signal wavelength is controllable using the polarization controller. An optional phase compensator is used to control polarization state of the output laser beam. In various embodiments the relative power distribution among multiple wavelengths may be controlled over a range of at least about 100:1.

Abstract: Two pulsed lasers (14) or sets of lasers propagate beams of pulses (20) having orthogonally related polarization states. A beam combiner (24) combines the orthogonal beams to form a combined beam propagating along a common beam path (16) to intersect an optical modulator (30) that selectively changes the polarization state of selected pulses of either beam to provide a composite beam (18) including similarly polarized pulses from the orthogonal beams. The composite polarized beam has a composite average power and a composite repetition rate that are greater than those provided by either laser. The optical modulator can also selectively control the polarization states of pulses from either laser to pass through or be blocked by a downstream polarizer (32). Additional modulators may facilitate pulse shaping of the pulses. The system is scalable by addition of sets of single lasers or pairs of lasers with beam combiners and modulators.

Abstract: An EUV light generation system includes a driver laser comprising a master oscillator such as a semiconductor laser, a spatial filter, gas slab amplification devices, relay optical systems, and high-speed axial-flow amplifiers. The slab amplification devices include beam adjusting optical units disposed, respectively, at input and output sides of the slab amplifiers SA to convert the beam profile and/or polarization direction and/or an elongated direction of the beam profile with the slab amplifiers is parallel to a free space axis AF of the slab waveguides, i.e. parallel to the discharge electrodes.

Abstract: A system includes a chamber, a laser beam apparatus configured to generate a laser beam to be introduced into the chamber, a laser controller for the laser beam apparatus to control at least a beam intensity and an output timing of the laser beam, and a target supply unit configured to supply a target material into the chamber, the target material being irradiated with the laser beam for generating extreme ultraviolet light.

Abstract: An optical apparatus comprising a gain medium exhibiting polarisation dependent absorption along two axes, the gain medium having a weakly absorbing axis and a strongly absorbing axis, an optical pump source arranged to direct pump light towards a first face of the gain medium such that the pump light entering the gain medium has a component of its polarisation parallel to the weakly absorbing axis, a polarisation modifying apparatus and one or more reflectors which are together arranged to modify the polarisation of pump light which exits the gain medium through a second face of the gain medium, and to direct the pump light with modified polarisation back towards said second face of the gain medium.

Abstract: Described herein is a laser (1) having a cavity for supporting oscillation of an electromagnetic signal to provide lasing action. A gain element (5) provides a source of stimulated emission for amplifying the oscillating signal. The laser also includes a wavelength selective element (7), which includes a reflecting element and a polarization modifying element. The reflecting element selectively defines a predetermined wavelength and the polarization modifying element selectively modifies the polarization of the signal component at the predetermined wavelength so as to provide high selectivity. The wavelength selective element (7) rotates the signal polarization at the predetermined wavelength into an orthogonal state. A polarization filter (9) filters out the signal components having wavelengths not corresponding to the predetermined wavelength and a polarization rotation element (11) again rotates the polarization of the signal into an orthogonal state.

Abstract: The invention is directed to the provision of a wavelength conversion-type ultraviolet light source apparatus that can obtain a stable output. A light source apparatus according to one mode of the invention includes: a laser light source 1 which produces fundamental light L1; at least one nonlinear optical crystal 3 which takes the fundamental light L1 or a harmonic thereof as incident light and outputs wavelength-converted light L2; and polarization adjusting means 2 which is placed in an optical path of the incident light and causes an output of the wavelength-converted light L2 to change by changing its refractive index for a polarized component of the incident light. The polarization adjusting means 2 changes the amount of change of the refractive index in accordance with an electrical signal output from a photodetector 7.

Abstract: A control system and apparatus for use with an ultra-fast laser is provided. In another aspect of the present invention, the apparatus includes a laser, pulse shaper, detection device and control system. A multiphoton intrapulse interference method is used to characterize the spectral phase of laser pulses and to compensate any distortions in an additional aspect of the present invention. In another aspect of the present invention, a system employs multiphoton intrapulse interference phase scan. Furthermore, another aspect of the present invention locates a pulse shaper and/or MIIPS unit between a laser oscillator and an output of a laser amplifier.

Abstract: A master oscillator may include: a pumping laser that outputs pumping light; a seed laser that is oscillated by the pumping light; an amplifier that amplifies the pulsed laser light outputted by the seed laser using the pumping light; at least one optical shutter disposed in the optical path between the seed laser and the amplifier; and a controller that causes the pumping laser to oscillate continuously at a predetermined repetition rate and that controls the optical shutter to open and close.

Abstract: A system includes a chamber, a laser beam apparatus configured to generate a laser beam to be introduced into the chamber, a laser controller for the laser beam apparatus to control at least a beam intensity and an output timing of the laser beam, and a target supply unit configured to supply a target material into the chamber, the target material being irradiated with the laser beam for generating extreme ultraviolet light.

Abstract: A laser and monitoring system is provided. In another aspect of the present invention, the system includes a laser, pulse shaper and detection device. A further aspect of the present invention employs a femtosecond laser and binary pulse shaping (BPS). Still another aspect of the present invention uses a laser beam pulse, a pulse shaper and a SHG crystal. In yet another aspect of the present invention, a multiphoton intrapulse interference phase scan (hereinafter “MIIPS”) method is used to characterize the spectral phase of femtosecond laser pulses and to correct them. A further aspect of the system of the present invention is employed to monitor environmental chemicals and biological agents, including toxins, explosives, and diseases.

Abstract: A GaN-based semiconductor laser (1) emits first laser light of a single polarization and having a first wavelength. An optical resonator (30) includes a solid-state laser medium which is excited by incidence of the laser light and which oscillates second laser light having a second wavelength different from the first wavelength. A polarization switch (6) switches over at least one of polarization directions of the first laser light and the second laser light to thereby change the wavelength of laser light to be emitted from the optical resonator (30) or the intensity ratio between a plurality of laser light to be emitted from the optical resonator (30). With the above arrangement, a plurality of laser light can be used effectively.

Abstract: The invention relates to a device (1) for generating short pulses, said device being characterized in that it comprises: a polarized pulse laser (10, 2, 3) having a polarization direction; a bi-refringent optical fiber (6) having bi-refringence axes, wherein said polarization direction is not co-linear with said bi-refringence axes; an output polarizer (9) provided at the output of said fiber, said polarizer being capable of selecting a polarization at the output of said fiber; wherein said pulse laser in a longitudinally quasi-single mode laser.

Abstract: A degree of polarization control device includes: a calcium fluoride crystal substrate for transmitting a laser beam; a polarization monitor for measuring the degree of polarization of a laser beam transmitted through the calcium fluoride crystal substrate; and a controller for controlling the rotation angle of the calcium fluoride crystal substrate according to the degree of polarization measured by the polarization monitor; the calcium fluoride crystal substrate being formed by a flat plate having a laser beam entering surface and a laser beam exiting surface running in parallel with the (111) crystal face, the Brewster angle being selected for the incident angle, the rotation angle around the [111] axis operating as a central axis being controlled by the controller.

Abstract: Provided is a fiber laser including a mode filter for selectively attenuating, among modes included in laser light propagating through a multi-mode fiber, any mode other than a radially polarized mode. Among the modes included in the laser light propagating through the multi-mode fiber, the fiber laser causes the radially polarized mode to resonate, so as to emit radially polarized laser light. The mode filter includes a long-period fiber grating obtained by writing, to a multi-mode fiber capable of guiding the radially polarized mode, a grating for selectively attenuating any waveguide mode other than the radially polarized mode.

Abstract: In the case of a lens array type homogenizer optical system, the incident angle and intensity of a laser beam 1 entering a large-sized lens (long-axis condenser lens 22) of a long-axis condensing optical system, which is provided on the rear side, are changed for every shot by performing laser irradiation while long-axis lens arrays 20a and 20b are reciprocated in a direction corresponding to a long axial direction of a linear beam (X-direction). Therefore, vertical stripes are significantly reduced. Further, the incident angle and intensity of a laser beam 1 entering a large-sized lens (projection lens 30) of a short-axis condensing optical system, which is provided on the rear side, are changed for every shot by performing laser irradiation while short-axis lens arrays 26a and 26b are reciprocated in a direction corresponding to a short axial direction of a linear beam (Y-direction). Therefore, horizontal stripes are significantly reduced.

Abstract: A degree of polarization control device includes: a calcium fluoride crystal substrate for transmitting a laser beam; a polarization monitor for measuring the degree of polarization of a laser beam transmitted through the calcium fluoride crystal substrate; and a controller for controlling the rotation angle of the calcium fluoride crystal substrate according to the degree of polarization measured by the polarization monitor; the calcium fluoride crystal substrate being formed by a flat plate having a laser beam entering surface and a laser beam exiting surface running in parallel with the (111) crystal face, the Brewster angle being selected for the incident angle, the rotation angle around the [111] axis operating as a central axis being controlled by the controller.

Abstract: An ultra-short pulsed laser system comprises an optical combiner, optical amplifier, optical pulse compressor, and optical separator. The optical combiner is configured to combine a primary optical pulse with a secondary optical signal to generate a combined optical signal. The primary optical pulse and the secondary optical signal have a distinguishable characteristic. The optical amplifier is configured to optically amplify the combined optical signal. The optical pulse compressor is configured to compress at least the primary optical pulse contained within the optically amplified combined optical signal and output a compressed combined optical signal. The optical separator is configured to separate the compressed combined optical signal into an output primary optical pulse and an output secondary optical signal according to the distinguishable characteristic.

Abstract: A wavelength conversion laser light source, including a solid-state laser medium configured to generate fundamental light; a wavelength conversion element configured to convert the fundamental light into second harmonic light which has a higher frequency than the fundamental light; and a conductive material in contact with the wavelength conversion element, wherein the wavelength conversion element includes a polarization inverted structure formed with a polarization inversion region, and a first lateral surface which perpendicularly intersects with the polarization inversion region, and the conductive material is in contact with the first lateral surface.

Abstract: A laser source device includes: a light emission unit which emits laser beam having first wavelength; a first mirror which selectively reflects S-polarized light contained in the first wavelength laser beam emitted from the light emission unit in a direction different from the direction toward the light emission unit and transmits second wavelength laser beam; a second mirror which receives laser beam reflected by the first mirror and reflects laser beam having first wavelength and contained in the received laser beam toward the first mirror; and a wavelength conversion element disposed between the first mirror and the second mirror and converts at least a part of S-polarized light contained in the received first wavelength laser beam into laser beam having second wavelength.

Abstract: A driver laser for an extreme ultra violet light source device capable of suppressing self-oscillation light, amplifying a laser beam efficiently, and reducing a device size. The driver laser has an oscillator for generating a laser beam to output the generated laser beam, and at least one amplifier for amplifying the laser beam output from the oscillator to output the amplified laser beam. The amplifier includes a discharge unit which amplifies the laser beam by using energy of a laser medium excited by discharge, a feedback mirror which leads the laser beam output from the discharge unit to the discharge unit, a polarizer which leads the laser beam output from the oscillator into the discharge unit and also reflects the laser beam output from the discharge unit to a predetermined direction, and a self-oscillation light filter which attenuates self-oscillation light output from the discharge unit.

Abstract: A multi-beam laser beam control system includes a laser transmitter configured to emit light in a plurality of beamlets. A sensor is configured to receive light from the beamlets. A processor is communicably coupled to the sensor and configured to compute a relative phase of a wavefront of at least one beamlet based on output from the sensor. A controller is communicably coupled to the processor and to the laser transmitter. The controller is configured to adjust a phase of at least one of the beamlets.

Abstract: Techniques, devices and applications of polarization stable lasers to provide laser operations against changes, variations or fluctuations in optical polarization in a laser cavity.

Abstract: A mode-locked laser employs a coupled-polarization scheme for efficient longitudinal pumping by reshaped laser diode bars. One or more dielectric polarizers are configured to reflect a pumping wavelength having a first polarization and to reflect a lasing wavelength having a second polarization. An asymmetric cavity provides relatively large beam spot sizes in gain medium to permit efficient coupling to a volume pumped by a laser diode bar. The cavity can include a collimation region with a controlled beam spot size for insertion of a saturable absorber and dispersion components. Beam spot size is selected to provide stable mode locking based on Kerr lensing. Pulse durations of less than 100 fs can be achieved in Yb:KGW.

Abstract: Provided is a fiber laser including a mode filter for selectively attenuating, among modes included in laser light propagating through a multi-mode fiber, any mode other than a radially polarized mode. Among the modes included in the laser light propagating through the multi-mode fiber, the fiber laser causes the radially polarized mode to resonate, so as to emit radially polarized laser light. The mode filter includes a long-period fiber grating obtained by writing, to a multi-mode fiber capable of guiding the radially polarized mode, a grating for selectively attenuating any waveguide mode other than the radially polarized mode.

Abstract: Methods and systems for generating high energy, mode locked, femtosecond and picosecond laser pulses are disclosed, including generating electromagnetic radiation from a pump laser; coupling the electromagnetic radiation to a rare Earth doped fiber using a pump/signal coupler; coupling the output from the rare Earth doped fiber to a first fiber; coupling a bandpass filter to the first fiber output and to a second fiber; coupling a first in-line polarization controller to the second fiber output and an in-line polarization beam splitter comprising a non-polarization maintaining fiber output and a polarization maintaining fiber output configured to emit an output laser pulse; coupling a polarization insensitive isolator to the non-polarization maintaining fiber output of the in-line polarization beam splitter and to a second in-line polarization controller; coupling a third fiber output to the second in-line polarization controller and to the pump/signal coupler. Other embodiments are described and claimed.

Abstract: Methods and systems for generating high energy, mode locked, femtosecond and picosecond laser pulses are disclosed, including generating electromagnetic radiation from a pump laser; coupling the electromagnetic radiation to a rare Earth doped fiber using a pump/signal coupler; coupling the output from the rare Earth doped fiber to a first fiber; coupling a bandpass filter to the first fiber output and to a second fiber; coupling a first in-line polarization controller to the second fiber output and an in-line polarization beam splitter comprising a non-polarization maintaining fiber output and a polarization maintaining fiber output configured to emit an output laser pulse; coupling a polarization insensitive isolator to the non-polarization maintaining fiber output of the in-line polarization beam splitter and to a second in-line polarization controller; coupling a third fiber output to the second in-line polarization controller and to the pump/signal coupler. Other embodiments are described and claimed.

Abstract: An optical arrangement comprising first and second guided structures for providing first and second beams of electromagnetic energy and a node for coherently combining said first and second beams in free space, that is, with an unguided structure. In the illustrative embodiment, the first and second structures are first and second fiber oscillators. The first and second fiber oscillators may be of unequal lengths. The node may be implemented with a polarizing beam splitter or a semi-reflective surface. Beam shaping optics are included in the node to collimate the first and second beams and provide a flat profile mode thereof. The outputs of plural first and second fiber oscillators are combined via plural nodes to provide a single high energy output beam. Amplifying elements may be disposed between nodes. The plural nodes may be disposed in a single integrated structure along with an outcoupler mirror to coherently phase lock the outputs of the plural oscillators.

Abstract: An improved laser source for use in a distributed temperature sensing (DTS) system (and DTS systems employing the same) includes a laser device and drive circuitry that cooperate to emit an optical pulse train at a characteristic wavelength between 1050 nm and 1090 nm. An optical amplifier, which is operably coupled to the laser device, is adapted to amplify the optical pulse train for output over the optical fiber sensor of the DTS system. In the preferred embodiment, the laser device operates at 1064 nm and outputs the optical pulse train via an optical fiber pigtail that is integral to its housing. The optical power of the optical pulse train generated by the laser source is greater than 100 mW, and preferably greater than 1 W, at a preferred pulse repetition frequency range between 1 and 50 kHz, and at a preferred pulse width range between 2 and 100 ns.

Abstract: A process and a device is described to avoid the depolarization of linear-polarized light during the transmission of light through crystals exhibiting a {111} or {100} crystal plane, respectively, and a <100> or <111> crystal axis, respectively. The device is characterized in that the linear-polarized light meets the surface of the crystals in an angle of 45-75°, whereby the surface is formed by the {111} or the {100} plane. The crystal is arranged in such a way that upon entering the crystal, the light spreads along the <100> or <111> crystal axis, respectively, as parallel as possible, and/or that the device comprises a unit for temperature equalization to avoid a thermal gradient in the crystal.

Abstract: A laser irradiation apparatus is provided in which the occurrence of adverse effects on an object to be irradiated with a laser beam due to the difference in the polarization state between pulsed laser beams can be prevented or significantly reduced when the pulsed laser beams emitted from two laser light sources are guided to pass through the same optical path for irradiation of an object to be irradiated with the pulsed laser beams. The laser irradiation apparatus is provided with a first laser light source 3, a second laser light source 4, an optical path combining optical member 7 which guides the pulsed laser beams emitted from the first laser light source 3 and the second laser light source 4 to pass through the same optical path, and a polarization control member 9 which controls polarization state of the pulsed laser beam from the optical path combining optical member 7.