Abstract: A tunable external cavity laser with dual gain chips, including: a polarization beam splitter having a beam splitting surface arranged at an angle of 45° with respect to a first direction and a second direction perpendicular to the first direction; a first gain chip arranged in the first direction; a second gain chip arranged in the second direction; a feedback cavity arranged in the first direction, wherein the feedback cavity and the first gain chip are respectively arranged on two opposite sides of the polarization beam splitter, and the feedback cavity includes at least one independent Fabry-Perot etalon, at least one air gap Fabry-Perot cavity and a mirror that are arranged in the first direction. The polarization beam splitter and the two gain chips cooperate to share the feedback cavity, so that a wavelength and a phase may be adjusted, and a larger tuning range may be obtained.

Abstract: A vertical-external-cavity surface-emitting laser (VECSEL) and a method of forming the VECSEL is disclosed. The VECSEL includes a heat sink; a heat spreader or heat spreader formed on a top surface of the heat sink, where the heat spreader comprises a first material having a first refractive index; and a high contrast grating formed on a top surface of the heat spreader or active region, wherein the high contrast grating comprises an active region and the high contrast grating comprising a second material having a second refractive index, the second refractive index is greater than the first refractive index.

Abstract: Disclosed are an optical signal outputting device and method, and a storage medium. The device includes a pump laser, first fiber grating and target fiber grating connected seriatim, the pump laser being configured to emit a first optical signal to the first fiber grating upon receiving a target waveband optical signal transmission instruction, and convert a second waveband optical signal into a target waveband optical signal by resonance upon receiving an optical signal adjusting instruction, then output the same; the first fiber grating being configured to filter the first optical signal to obtain a first waveband optical signal and send it to the target fiber grating; and the target fiber grating being configured to filter the first waveband optical signal to obtain a second waveband optical signal and the target waveband optical signal to use one of them to deliver the optical signal adjusting instruction to the pump laser.

Abstract: A laser processing system includes a laser beam source that produces a raw laser beam; a beam expansion system that receives the raw laser beam and produces an expanded laser beam; a homogenization system that receives the expanded laser beam and produces a laser beam that is homogenized and has a line-shaped beam cross section in the processing plane, wherein the homogenization system includes a first homogenization arrangement that homogenizes along the short axis and a second homogenization arrangement for homogenization along the long axis, each of the homogenization arrangements includes optical elements that split the laser beam into a multiplicity of partial beams and a condenser system that superposes the partial beams in a superposition plane, and the first homogenization arrangement includes a first condenser system with at least one first mirror and the second homogenization arrangement includes a second condenser system with at least one second mirror.

Abstract: A radiation-emitting semiconductor chip includes a semiconductor layer sequence having an active layer for generating electromagnetic radiation. The semiconductor chip also includes a reflector at a side surface of the semiconductor layer sequence having a reflector surface facing the semiconductor layer sequence and extending obliquely with respect to the active layer. The semiconductor chip further includes a top surface extending transversely with respect to the reflector surface and having a first emission region. The semiconductor chip additionally includes a further reflector situated opposite the reflector. The semiconductor chip is configured such that electromagnetic radiation generated in the active layer during operation is reflected by the reflector and emerges from the semiconductor chip via the emission region of the top surface. A main emission direction of the emerging electromagnetic radiation together with the active layer form an emergence angle of between 30° and 80° inclusive.

Abstract: A laser device includes a gain medium, a zero-degree reflective mirror, a first retro-reflective mirror, a second retro-reflective mirror, and an output coupling mirror. The gain medium is used to generate radiation light; the zero-degree reflective mirror has a common optical axis with the gain medium, and the zero-degree reflective mirror is used to totally reflect second-direction radiation light that is incident on the zero-degree reflective mirror in an optical-axis direction; the first-direction radiation light and the first emitted light are spaced from and parallel to each other in opposite directions; the first emitted light and the second emitted light are spaced from and parallel to each other in opposite directions; a resonant cavity is formed between the zero-degree reflective mirror and the output coupling mirror; the output coupling mirror is used to transmit and output first partial radiation light, and reflect second partial radiation light.

Abstract: A laser processing system includes a laser beam source that produces a raw laser beam; a beam expansion system that receives the raw laser beam and produces an expanded laser beam; a homogenization system that receives the expanded laser beam and produces a laser beam that is homogenized and has a line-shaped beam cross section in the processing plane, wherein the homogenization system includes a first homogenization arrangement that homogenizes along the short axis and a second homogenization arrangement for homogenization along the long axis, each of the homogenization arrangements includes optical elements that split the laser beam into a multiplicity of partial beams and a condenser system that superposes the partial beams in a superposition plane, and the first homogenization arrangement includes a first condenser system with at least one first mirror and the second homogenization arrangement includes a second condenser system with at least one second mirror.

Abstract: A VCSEL can include: a substrate that passes light therethrough; a phase matching layer over a top mirror stack; a first metal layer over the phase matching layer; and an end metal region over the first metal layer. The phase matching layer and first metal layer have a cooperative thickness to provide reflectivity of at least a predetermined reflectivity threshold for the emission wavelength. A method of making a VCSEL can include: providing a substrate; forming a first mirror stack above the substrate; forming an active region above the first mirror stack; and forming a reflective end above the active region, the reflective end having a phase matching layer and a first metal layer. The phase matching layer and first metal layer have a combined thickness for the reflective end to have a reflectivity of at least a predetermined reflectivity threshold for an emission wavelength of the VCSEL.

Abstract: An optical lens, mold for optical lens and manufacturing method thereof are provided, wherein the optical lens includes a spiral surface spiraling around an axial direction and an intermediate structure around which the spiral surface spirals, the intermediate structure extends axially relative to a side of the spiral surface, and two ends of the spiral surface defines a stepped difference. The structure of the mold and the optical lens are correspondingly complementary. The manufacturing method of the mold includes following steps of: providing a base, the base including a processing surface; processing the processing surface to form the spiral surface, the intermediate structure and the stepped difference of the mold.

Abstract: A laser assembly (1710) for generating an assembly output beam (1712) includes a laser subassembly (1716) including a first laser module (1716A) and a second laser module (1716B), a transform assembly (1744), and a beam combiner (1746). The first laser module (1716A) emits a plurality of spaced apart first laser beams (1720A). The second laser module (1716B) emits a plurality of spaced apart second laser beams (1720B). The transform assembly (1744) is positioned in a path of the laser beams (1720A) (1720B). The transform assembly (1744) directs the laser beams (1720A) (1720B) to spatially overlap at a focal plane of the transform assembly (1744). The beam combiner (1746) is positioned at the focal plane that combines the lasers beams (1720A) (1720B) to provide a combination beam. The laser beams (1720A) (1720B) directed by the transform assembly (1744) impinge on the beam combiner (1746) at different angles.

Abstract: In a right-handed XYZ coordinate system, a dichroic-mirror array of the present disclosure includes a first group in which m (m?2) dichroic mirrors DA1 to DAm are arranged parallel to each other along a positive direction of an X axis and a second group in which n (n?2) dichroic mirrors DB1 to DBn are arranged parallel to each other along a negative direction of the X axis. Incident surfaces of the DA1 to DAm and incident surfaces of the DB1 to DBn are perpendicular to an XZ plane. A slope of straight lines with normal lines of the incident surfaces of the DA1 to DAm projected onto the XZ plane are negative, and a slope of straight lines with normal lines of incident surfaces of DB1 to DBn projected onto the XZ plane are positive.

Abstract: The light source unit includes a base provided with an opening, a support member fixed to the base at the opening, and a light source assembly fixed to the support member at the opening. The light source assembly includes a light source emitting laser light, a lens disposed on an optical axis of the laser light, and a holding member holding the light source and the lens. The support member has a convex receiving surface extending along the spherical surface so as to surround the optical axis when viewed from a direction parallel to the optical axis. The light source assembly is fixed to the support member by coupling the holding member to the receiving surface at a contact portion with the receiving surface. The receiving surface has a portion located on a side away from the optical axis with respect to a coupling part with the holding member.

Abstract: A fiber laser apparatus includes: a short-length type fiber to which an active element is added and that has a length of 300 mm or less: a ferrule attached to an end of the fiber; and a housing that accommodates the fiber and supports the fiber with the ferrule. Each of the housing and the ferrule is composed of a material having a first thermal expansion coefficient that is equal to or have a predetermined difference from a second thermal expansion coefficient of a raw material of the fiber. The predetermined difference between the first and second thermal expansion coefficients is within ?8.6×10?6 to 11.4×10?6/K.

Abstract: A surface emission laser formed of a group III nitride semiconductor includes a first conductivity type first clad layer; a first conductivity type first guide layer on the first clad layer; a light-emitting layer on the first guide layer; a second guide layer on the light-emitting layer; and a second conductivity type second clad layer on the second guide layer. The first or second guide layer internally includes voids periodically arranged at square lattice positions with two axes perpendicular to one another as arrangement directions in a surface parallel to the guide layer. The voids have a polygonal prism structure or an oval columnar structure with a long axis and a short axis perpendicular to the long axis in the parallel surface, and the long axis is inclined with respect to one axis among the arrangement directions of the voids.

Abstract: A method of removing a substrate from III-nitride based semiconductor layers with a cleaving technique. A growth restrict mask is formed on or above a substrate, and one or more III-nitride based semiconductor layers are grown on or above the substrate using the growth restrict mask. The III-nitride based semiconductor layers are bonded to a support substrate or film, and the III-nitride based semiconductor layers are removed from the substrate using a cleaving technique on a surface of the substrate. Stress may be applied to the III-nitride based semiconductor layers, due to differences in thermal expansion between the III-nitride substrate and the support substrate or film bonded to the III-nitride based semiconductor layers, before the III-nitride based semiconductor layers are removed from the substrate. Once removed, the substrate can be recycled, resulting in cost savings for device fabrication.

Abstract: Embodiments of the disclosure provide transmitters for light detection and ranging (LiDAR). The transmitter includes a laser source, a light collimator, and a beam shifter. The laser source is configured to provide a native laser beam. The light collimator is configured to collimate the native laser beam to form an input laser beam transmitting along a lateral direction. The beam shifter is configured to shift the input laser beam along a vertical direction perpendicular to the lateral direction by a displacement to form an output laser beam. The output laser beam and the input laser beam are parallel to each other.

Abstract: Methods and systems for crystallizing a thin film provide a laser beam spot that is continually advanced across the thin film to create a sustained complete or partial molten zone that is translated across the thin film, and crystallizes to form uniform, small-grained crystalline structures or grains.

Abstract: A semiconductor optical amplifier includes: a light source part that is formed on a substrate, the substrate including a substrate surface; and an optical amplification part that amplifies propagation light propagating in a predetermined direction from the light source part and that emits the propagation light amplified in an emission direction intersecting with the substrate surface, the optical amplification part including a conductive region extending in the predetermined direction from the light source part along the substrate surface and a non-conductive region formed on a periphery of the conductive region, the conductive region including a reflection part that reflects the propagation light in a direction intersecting with the predetermined direction when viewed from a direction vertical to the substrate surface.

Abstract: To realize a reservoir computing system with a small size and reduced learning cost, provided is a laser apparatus including a laser; a feedback waveguide that is operable to feed light output from the laser back to the laser; an optical splitter that is provided in a path of the feedback waveguide and is operable to output a portion of light propagated in the feedback waveguide to outside; and a first ring resonator that is operable to be optically connected to the feedback waveguide, as well as a reservoir computing system including this laser apparatus.

Abstract: A method of producing gallium-doped zinc oxide films with enhanced conductivity. The method includes depositing a gallium-doped zinc oxide film on a substrate using a pulsed laser and subjecting the deposited gallium-dope zinc oxide film to a post-treatment effecting recrystallization in the deposited film, wherein the recrystallization enhances the conductivity of the film. Another method of producing gallium-doped zinc oxide films with enhanced conductivity. The method includes the steps of depositing a gallium-doped zinc oxide film on a substrate using a pulsed laser and subjecting the deposited gallium-dope zinc oxide film to an ultraviolet laser beam resulting in recrystallization in the film, wherein the recrystallization enhances the conductivity of the film. A film comprising gallium-doped zinc oxide wherein the film contains a recrystallized grain structure on its surface.

Abstract: Physiological parameter detecting apparatuses and methods of detecting the physiological parameters are provided. A physiological parameter detecting apparatus includes: a light source configured to emit a light onto a region of an object; an optical path converter configured to receive the light returning from the object and convert an optical path of the received light; an optical detector configured to detect the light that has the converted optical path; and a controller configured to extract physiological information of the object from the detected light.

Abstract: A heating device is provided. The heating device includes a conveyance member that conveys a substrate between a heating position and a non-heating position, a support member that is provided on the conveyance member and that supports the substrate, a heater provided at the heating position and operable to heat a first surface of the substrate, and a heat reflecting plate attached to the conveyance member in facing relation to a second surface of the substrate opposite to the first surface.

Abstract: A light source device includes a package, one or more semiconductor lasers each having an emission surface, a light-transmissive cover, and an optical member. The package includes an inner bottom surface and inner lateral surfaces, and a recess defined by the inner bottom surface and the inner lateral surfaces and having an open end. The one or more semiconductor lasers are arranged on the inner bottom surface. The light-transmissive cover covers the open end of the recess. The optical member is arranged on an upper surface of the cover and is configured to mix light. The one or more semiconductor lasers are arranged so that their emission surfaces are respectively oblique to their adjacent inner lateral surface when viewed from above, and the inner lateral surface has a reflecting region arranged inclined with respect to the bottom surface.

Abstract: A two-dimensional photonic crystal surface emitting laser has, in a plate-shaped base body, a two-dimensional photonic crystal layer in which modified refractive index region pairs are periodically arranged and an active layer provided on one side of the base body, each of the modified refractive index region pairs including a first modified refractive index region and a second modified refractive index region having refractive indexes different from a refractive index of the base body, wherein an area of a planar shape of the first modified refractive index region is larger than or equal to an area of a planar shape of the second modified refractive index region, and a thickness of the first modified refractive index region is smaller than a thickness of the second modified refractive index region.

Abstract: A two-dimensional photonic-crystal surface-emitting laser 10 includes: a two-dimensional photonic crystal (two-dimensional photonic crystal layer 12) including a plate-shaped base body 121 having a predetermined size in which modified refractive index areas 122 whose refractive index differs from the base body are periodically arranged in a two-dimensional pattern; an active layer 11 provided on one side of the two-dimensional photonic crystal; and first and second electrodes 15 and 16 facing each other across the two-dimensional photonic crystal and the active layer 11, for supplying an electric current to the active layer 11. The modified refractive index areas 122 are provided in such a manner that the in-plane occupancy of those areas 122 in the base body 121 decreases, or the lattice constant for those areas 122 increases, in the direction from an outer edge toward the center of a current passage region 21 which is a region where the electric current passes through the two-dimensional photonic crystal.

Abstract: A laser apparatus including a pulsed laser radiation source is disclosed, wherein the laser radiation has spectral components in at least two wavelength ranges W1, W2 that differ from one another, and a dispersion control element including at least one dielectric multilayer mirror, wherein the laser radiation is reflected one or more times at the multilayer mirror. The multilayer mirror is reflective in the two wavelength ranges W1, W2, and the reflection of the spectral component in the second wavelength range W2 has a time delay relative to the reflection of the spectral component in the first wavelength range W1 such that the spectral components of the laser radiation reflected at the multilayer mirror in the two wavelength ranges W1, W2 coincide in time in an interaction center of the laser apparatus, and a nonlinear optical element is situated in the interaction center.

Abstract: A semiconductor laser diode (LD) having an optical grating is disclosed. The LD includes a lower cladding layer that buries the optical grating, an active layer, and an upper cladding layer. The active layer has a multi-quantum well (MQW) structure of barrier layers and well layers alternately arranged. The MQW structure further includes intermediate layers between the barrier layers and the well layers. The intermediate layers have a lattice constant between that of the barrier layers and that of the well layers. Each intermediate layer has a thickness thinner than 1 nm.

Abstract: An optical coherence tomography (OCT) system combining multiple wavelengths is generally described. In an example, the OCT system includes multiple wavelength swept light sources. The system further includes an interferometer into which light from the light sources is directed and a detector configured to produce an imaging sample signal based on light received from the interferometer. The system also includes a splitter configured to split light from at least one of light sources before the light reaches the interferometer. The system also includes a wavelength reference filter having an equal interval frequency comb and a signal processing circuit. The wavelength reference filter is configured to produce a sequential clock waveform from light received from the splitter, and the signal processing circuit is configured to resample the imaging sample signal based on the sequential clock waveform.

Abstract: An apparatus and method for laser-assisted machining (LAM) of bone without raising the temperature of the surrounding bone is discussed. The method of LAM of bone involves determining a target bone needing to be machined an then scanning a high power density laser beam along the bone at a machining rate that produces low-heat affected zones (HAZ) on the target bone. The process and apparatus is advantageous over conventional technologies because it provides a chemically clean, coherent, and monochromatic beam to the region to be machined.

Abstract: A laser resonator includes an active material, which amplifies light associated with an optical gain of the resonator, and passive materials disposed in proximity with the active material. The resonator oscillates over one or more optical modes, each of which corresponds to a particular spatial energy distribution and resonant frequency. Based on a characteristic of the passive materials, for the particular spatial energy distribution corresponding to at least one of the optical modes, a preponderant portion of optical energy is distributed apart from the active material. The passive materials may include a low loss material, which stores the preponderant optical energy portion distributed apart from the active material, and a buffer material disposed between the low loss material and the active material, which controls a ratio of the optical energy stored in the low loss material to a portion of the optical energy in the active material.

Abstract: A semiconductor laser device includes: a semiconductor laser array in which a plurality of active layers that emit laser lights with a divergence angle ?S (>4°) in a slow axis direction are arranged; a first optical element that reflects first partial lights by a first reflecting surface and returns the first partial lights to the active layers; and a second optical element that reflects partial mode lights of second partial lights by a second reflecting surface and returns the partial mode lights to the active layers, the first reflecting surface forms an angle equal to or greater than 2° and less than (?S/2) with a plane perpendicular to an optical axis direction of the active layers, and the second reflecting surface forms an angle greater than (??S/2) and equal to or less than ?2° with the plane perpendicular to the optical axis direction of the active layers.

Abstract: A carrier structure (100), particularly for optical components, includes a carrier body (10) which is formed from ceramic with hollows (11), and at least one cover layer (21, 22) which is formed from glass, arranged on at least one surface of the carrier body (10), and is connected to the carrier body (10) by means of at least one bond connection (23, 24) produced by means of anodic bonding. Methods for producing the carrier structure (100) and the use of the carrier structure as a mirror body, carrier for optical components and/or mechanical carrier for dynamically moved components are also described.

Abstract: One embodiment of the present invention is a unique engine hot section component having a coating system operative to reduce heat transfer to the hot section component. Another embodiment is a unique method for making a gas turbine engine hot section component with a coating system. Other embodiments include apparatuses, systems, devices, hardware, methods, and combinations for gas turbine engines, hot section components and coating systems. Further embodiments, forms, features, aspects, benefits, and advantages of the present application shall become apparent from the description and figures provided herewith.

Abstract: The present disclosure provide methods for forming nanowire structures with desired materials horizontal gate-all-around (hGAA) structures field effect transistor (FET) for semiconductor chips. In one example, a method of forming nanowire structures on a substrate includes supplying an oxygen containing gas mixture to a multi-material layer on a substrate in a processing chamber, wherein the multi-material layer includes repeating pairs of a first layer and a second layer, the first and the second layers having a first group and a second group of sidewalls respectively exposed through openings defined in the multi-material layer, and selectively forming an oxidation layer on the second group of sidewalls in the second layer.

Abstract: The invention relates to a laser resonator for generating frequency-converted laser radiation, comprising a laser-active solid-state medium and a wavelength conversion crystal. A transmissive optical element having a concavely curved surface for generating collimated laser radiation is arranged in the laser resonator.

Abstract: A light emitting device includes a first layer that generates light by an injection current, the first layer is provided with a first optical waveguide extending from a first light emitting section disposed on a first side surface to a first light reflecting section disposed on a second side surface, a second optical waveguide extending from the first light reflecting section to a second light reflecting section disposed on a third side surface, and a third optical waveguide extending from the second light reflecting section to a second light emitting section disposed on the first side surface, and an element of the group II or the group XII is diffused in the first light reflecting section and the second light reflecting section.

Abstract: An opto-electronic circuit board includes a substrate, a cavity, blind vias, metal layers, a first chip, a second chip, and the optical component. The substrate includes a first circuit layer, a second circuit layer, and a dielectric layer disposed between the first circuit layer and the second circuit layer. The cavity is disposed on the dielectric layer, in which the cavity extends from the first circuit layer to the second circuit layer. The blind vias are disposed at opposite sides of the cavity. The first chip is disposed on the second circuit layer with corresponding to one of the blind vias. The second chip is disposed on the second circuit layer with corresponding to the other one of the blind vias. The optical component is disposed in the cavity, in which the second surface of the optical component is connected to the first circuit layer.

Abstract: A laser includes a total reflective mirror, an output mirror, a discharge lamp, and an active laser medium. The total reflective mirror, the output mirror, and the discharge lamp define a resonant cavity. The active laser medium is filled in the resonant cavity. The total reflective mirror includes a microstructure. The microstructure is convex ring-shaped structure. The convex ring-shaped structure has a height and a width, and both the height and the width are in a range from about 0.5? to about 2?, while ? is a working wavelength of the laser.

Abstract: A laser includes a total reflective mirror, an output mirror, a discharge lamp, and an active laser medium. The total reflective mirror, the output mirror, and the discharge lamp define a resonant cavity. The active laser medium is filled in the resonant cavity. The total reflective mirror includes a microstructure. The microstructure is concave ring-shaped structure. The concave ring-shaped structure has a depth and a width, and both the depth and the width are in a range from about 0.5? to about 2?, while ? is a working wavelength of the laser.

Abstract: Disclosed is an ASE-free continuously tunable external resonator laser in which reduction in tuning range and decrease in output are suppressed. The external resonator laser comprises: a fixed support body which has a half mirror that partially reflects incident light and partially transmits incident light fixed therein; and a rotatory support body which is rotatably supported by the fixed support body by way of a shaft, and which has a laser chip that emits light, a collimator lens that collimates light emitted from the laser chip, and a diffraction grating that diffracts light emitted from the laser chip, fixed therein.

Abstract: A tunable laser source that includes multiple gain elements and uses a spatial light modulator in an external cavity to produce spectrally tunable output is claimed. Several designs of the external cavity are described, targeting different performance characteristics and different manufacturing costs for the device. Compared to existing devices, the tunable laser source produces high output power, wide tuning range, fast tuning rate, and high spectral resolution.

Abstract: An apparatus comprising an optical medium, a power splitter coupled to the optical medium, a first delay line coupled to the power splitter such that the power splitter is positioned between the first delay line and the optical medium, a first comb reflector coupled to the first delay line such that the first delay line is positioned between the first comb reflector and the power splitter, and a second comb reflector coupled to the power splitter but not the first comb reflector and not the first delay line. A method comprising receiving an optical signal, splitting the optical signal into a first split optical signal and a second split optical signal, delaying the first split optical signal, tuning the delayed first split optical signal, tuning the second split optical signal, and delaying the tuned second split optical signal.

Abstract: An optical gain architecture includes a pump source and a pump aperture. The architecture also includes a gain region including a gain element operable to amplify light at a laser wavelength. The gain region is characterized by a first side intersecting an optical path, a second side opposing the first side, a third side adjacent the first and second sides, and a fourth side opposing the third side. The architecture further includes a dichroic section disposed between the pump aperture and the first side of the gain region. The dichroic section is characterized by low reflectance at a pump wavelength and high reflectance at the laser wavelength. The architecture additionally includes a first cladding section proximate to the third side of the gain region and a second cladding section proximate to the fourth side of the gain region.

Abstract: The invention relates to an optical resonator, laser apparatus and a method of generating a laser beam inside an optical resonator. The optical resonator (100) includes an optical cavity (102) and an optical element (104.1, 104.2) at either end thereof, operable to sustain a light beam (108) therein, characterized in that each optical element (104.1, 104.2) is a phase-only optical element operable to alter a mode of the beam (108) as it propagates along the length of the optical resonator (100), such that in use the beam (108) at one end of the optical resonator (100) has a Gaussian profile while the beam (108) at the other end of the optical resonator (100) has a non-Gaussian profile.

Abstract: A ring resonator is connected to an optical amplifier. The ring resonator and optical amplifier are contained within the optical path of an optical resonator formed by a first and second reflector. The optical coupler branches part of the light conducting from the optical amplifier to the ring resonator within the optical resonator off to an output optical waveguide.

Abstract: A light emitting device includes a first semiconductor multilayer film mirror of a first conductivity type, a second semiconductor multilayer film mirror of a second conductivity type that is different from the first conductivity type, an active layer formed between the first semiconductor multilayer film mirror and the second semiconductor multilayer film mirror, a third semiconductor multilayer film mirror of a semi-insulating type formed between the first semiconductor multilayer film mirror and the active layer, and a contact layer of the first conductivity type formed between the third semiconductor multilayer film mirror and the active layer, and the third semiconductor multilayer film mirror is formed of a material having a bandgap energy higher than an energy of light generated in the active layer.

Abstract: A monolithic fixed optical delay generator includes an optical substrate having a front face and a back face. A front coating is on the front face and a back coating is on the back face. The front coating is (i) highly reflective to a first wavelength and highly transmissive to a second wavelength while the back coating is highly reflective to the second wavelength, or (ii) the front coating is highly reflective to the second wavelength and is highly transmissive to the first wavelength while the back coating is highly reflective to the first wavelength.

Abstract: A device for producing a coherent bi-color light source, including: an array substrate, a first laser tube driven by a first direct current signal, a second laser tube driven by a modulation signal coupled by a microwave signal and a second DC signal, a half wave plate, a birefringent crystal, a first quarter wave plate, a partially reflecting plane mirror, and a second quarter wave plate. The first laser tube and the second laser tube are fixed on the array substrate. The half wave plate, the birefringent crystal, the first quarter wave plate, the partially reflecting plane mirror, and the second quarter wave plate are disposed in sequence in an emission direction of a laser beam emitted by the first laser tube. The second laser tube is disposed opposite to the birefringent crystal.

Abstract: The present disclosure relates to a tunable laser module including a light gain area unit for outputting an optical signal; an optical distributor for separating the optical signal output from the light gain area unit; two comb reflection units for reflecting a part of optical signals separated by the optical distributor and allow a part of the optical signals to penetrate; two phase units for changing phases of the optical signals penetrating the two comb reflection units; an optical coupler for combining the optical signals of which the phases are changed by the two phase units; and an optical amplifier for amplifying the optical signal combined by the optical coupler, wherein the light gain area unit oscillates a laser by totally reflecting the optical signals reflected by the two comb reflection units.

Abstract: A tunable DBR laser including: an amplifier section, a part-reflecting optical output, a connection section connected to the amplifier section, and at least two wavelength-selective reflectors optically coupled to the amplifier section via the connection section. The connection section includes at least one MMI coupler and several waveguides, so that different optical paths lead from the amplifier section to the wavelength-selective reflectors and each of the different optical paths leads through the at least one MMI coupler and through one of the waveguides. The wavelength-selective reflectors differ from one another by having different reflection spectra and each of the wavelength-selective reflectors is connected to one of several outputs of the at least one MMI coupler. By activating a phase shifter, arranged in a course of at least one of the waveguides, the DBR laser can be switched between different resonators.