Abstract: A system for generating a shaped optical pulse is disclosed. The system includes a master oscillator for generating an initial optical pulse, which is then directed to a semiconductor optical amplifier to amplify a portion of the initial optical pulse. The amplified pulse is reflected from a fiber Bragg grating to spectrally clean the amplified pulse and the reflected portion is returned back through the semiconductor optical amplifier. The semiconductor optical amplifier is activated a second time to amplify the reflected portion of the pulse. The time delay between the two activations of the semiconductor optical amplifier is selected to generate an output pulse with desired duration and/or amplitude profile over time.

Abstract: An optical semiconductor device includes: an active region which includes an active layer which produces light when current is injected therein, a first diffraction grating layer having a first diffraction grating with a prescribed grating period, and a phase shift portion formed within the first diffraction grating layer, wherein the phase shift portion provides a phase shift not smaller than 1.5? but not larger than 1.83?; and a distributed reflection mirror region which is optically coupled to a first end of the active region as viewed along a direction of an optical axis, and which includes a second diffraction grating which reflects the light produced by the active region back into the active region.

Abstract: A semiconductor laser device assembly includes (A) a semiconductor laser element and (B) a diffraction grating that configures an external resonator, returns diffraction light other than zero-th order diffraction light to the semiconductor laser element, and outputs the zero-th order diffraction light to the outside. An extension direction of a diffraction surface of the diffraction grating and a main vibration direction of a field of a laser beam incident on the diffraction grating are substantially parallel to each other.

Abstract: A method of manufacturing a surface-emitting laser that allows precise alignment of the center position of a surface relief structure and that of a current confinement structure and formation of the relief structure by means of which a sufficient loss difference can be introduced between the fundamental transverse and higher order transverse mode. Removing the dielectric film on the semiconductor layers and the first-etch stop layer along the second pattern, using a second- and third-etch stop layer are conducted in single step after forming the confinement structure. The relief structure is formed by three layers including a lower, middle and upper layer, and total thickness of three layers is equal to the optical thickness of an odd multiple of ¼ wavelength (?: oscillation wavelength, n: refractive index of the semiconductor layer). The layer right under the lower layer is the second-etch stop layer and the first-etch stop layer is laid right on this etch stop layer.

Abstract: Laser device comprising: a laser source including a light emitting structure; a guide structure to deliver light generated by the emitting structure, this guide structure comprising at least a first portion and a second portion, the first portion housing a diffraction grating that forms a reflector of the laser source and cooperates with the emitting structure, the second portion being a waveguide that delivers light generated by the emitting structure and propagated in the first portion. The emitting structure is made using the III-V technology or II-VI technology, and the guide structure is made using the silicon technology.

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

Abstract: In the semiconductor laser including a diffraction grating in which a first diffraction grating region with a first pitch, a second diffraction grating region with a second pitch and a third diffraction grating region with the first pitch, an anti-reflection film coated on an end facet to the light-emitting side, and a reflection film coated on an opposite end facet, the first diffraction grating region is greater than the third diffraction grating region, and the second diffraction grating region is formed, in such a manner that phases of the first and third diffraction grating regions are shifted in a range of equal to or more than 0.6 ? to equal to or less than 0.9 ?, phases are successive on a boundary between the first and second diffraction grating regions and the phases are successive on a boundary between the second and third diffraction grating regions.

Abstract: Light emitting elements, and methods of producing the same, the light emitting elements including: a laminated structure, the laminated structure including a first compound semiconductor layer that includes a first surface and a second surface facing the first surface, an active layer that is in contact with the second surface of the first compound semiconductor layer, and a second compound semiconductor layer; where the first surface of the first compound semiconductor layer has a first surface area and a second surface area, the first and second surface areas being different in at least one of a height or a roughness, a first light reflection layer is formed on at least a portion of the first surface area, and a first electrode is formed on at least a portion of the second surface area.

Abstract: A light-emitting element includes a mesa structure in which a first compound semiconductor layer of a first conductivity type, an active layer, and a second compound semiconductor layer of a second conductivity type are disposed in that order, wherein at least one of the first compound semiconductor layer and the second compound semiconductor layer has a current constriction region surrounded by an insulation region extending inward from a sidewall portion of the mesa structure; a wall structure disposed so as to surround the mesa structure; at least one bridge structure connecting the mesa structure and the wall structure, the wall structure and the bridge structure each having the same layer structure as the portion of the mesa structure in which the insulation region is provided; a first electrode; and a second electrode disposed on a top face of the wall structure.

Abstract: The present invention provides a light source for light circuits on a silicon platform. A vertical laser cavity is formed by a gain region arranged between a first mirror structure and a second mirror structure, both acting as mirrors, by forming a grating region including an active material in a silicon layer in a semiconductor structure or wafer structure. A waveguide for receiving light from the region of the mirrors is formed within or to be connected to the region of the mirrors, and functions as an output coupler for the VCL. Thereby, vertical lasing modes are coupled to lateral in-plane modes of the in-plane waveguide formed in the silicon layer, and light can be provided to e.g. photonic circuits on a SOI or CMOS substrate in the silicon.

Abstract: Distributed feedback-laser diodes are provided. The distributed feedback-laser diode may include a substrate, a lower cladding layer having a grating on the substrate, an active layer disposed on the lower cladding layer, a first upper cladding layer disposed on the active layer, a phase-shift region extending in a first direction on the first upper cladding layer, and a ridge waveguide layer extending in a second direction crossing the first direction on the phase-shift region.

Abstract: A vertical cavity surface emitting laser (VCSEL) configured to operate in a gain switching regime includes a cavity that is terminated by reflectors at both ends for enabling a standing wave of optical radiation therebetween. The cavity comprises at least one quantum well, each of the quantum wells located at a position where a value of a standing wave factor for each quantum well is between zero and one, 0<?<1.

Abstract: An external cavity semiconductor laser light source comprises includes a semiconductor gain device operable to provide light amplification; a wavelength selection element including a diffraction grating; and light re-directors. The gain device, light re-directors and grating are arranged so that an optical resonator is established for light portions emitted by the gain device and diffracted by the diffraction grating. The resonator is an external cavity laser resonator. The light source is capable of varying an angle of incidence of radiation circulating in the resonator onto wavelength selection element to select a resonator radiation wavelength dependent on the angle of incidence.

Abstract: A monolithically integrated, tunable semiconductor laser with an optical waveguide, comprising a laser chip having epitaxial layers on a substrate and having first and second reflectors bounding an optical gain section and a passive section, wherein at least one of the reflectors is a distributed Bragg reflector section comprising a grating and configured to have a tunable reflection spectrum, wherein the laser is provided with a common earth electrode, wherein control electrodes are provided on the optical waveguide in at least the optical gain section and the at least one distributed Bragg reflector section, wherein the passive section is provided with an electrode or electrical tracking on the optical waveguide, the passive section is configured not to be drivable by an electrical control signal, and no grating is present within the passive section.

Abstract: A semiconductor laser is provided with one or more rear ports and one front port and with a multi-mode interference optical waveguide that has an active layer (light emitting layer) in all regions in plan view. The front port corresponds to an imaging point at which fundamental mode light forms an image in the active layer (light emitting layer) perpendicular to the waveguide direction of the multi-mode interference optical waveguide, and in plan view the front port is disposed along a central line, off center with respect to a central line, along the waveguide direction of the multi-mode interference optical waveguide.

Abstract: The invention relates to vertical cavity lasers (VCL) incorporating a reflectivity-modulated grating mirror (1) for modulating the laser output. A cavity is formed by a bottom mirror (4), an active region (3), and an outcoupling top grating mirror (1) formed by a periodic refractive index grating region in a layer structure comprising a p- and a n-doped semiconductor layer with an electrooptic material layer (12) arranged there between. The grating region comprises a grating structure formed by periodic perforations to change the refractive index periodically in directions normal to the oscillation axis. A modulated voltage (91) is applied in reverse bias between the n- and p-doped layers to modulate the refractive index of the electrooptic material layer (12) and thereby the reflectivity spectrum of the grating mirror (1).

Abstract: Tensile strained germanium is provided that can be sufficiently strained to provide a nearly direct band gap material or a direct band gap material. Compressively stressed or tensile stressed stressor materials in contact with germanium regions induce uniaxial or biaxial tensile strain in the germanium regions. Stressor materials may include silicon nitride or silicon germanium. The resulting strained germanium structure can be used to emit or detect photons including, for example, generating photons within a resonant cavity to provide a laser.

Abstract: In an embodiment, a distributed Bragg reflector (DBR) laser includes a gain section and a passive section. The gain section includes an active region, an upper separate confinement heterostructure (SCH), and a lower SCH. The upper SCH is above the active region and has a thickness of at least 60 nanometers (nm). The lower SCH is below the active region and has a thickness of at least 60 nm. The passive section is coupled to the gain section, the passive section having a DBR in optical communication with the active region.

Abstract: An Environmentally stable optical fiber mode-locked laser generating device having an achromatic quarter wave plate is disclosed. An optical fiber unit is formed of a polarization maintaining (PM) optical fiber, and a Bragg grating is formed on a first region from one end in direction to the other end, a gain material is doped on a core of a remaining second region. An optical coupling unit provides a pump laser input to one end of the optical fiber unit, and outputs a laser input from the optical fiber unit. A lens unit converts a laser output from the other end of the optical fiber unit and focuses the laser on a certain regime.

Abstract: Disclosed is a surface-emitting laser element including a semiconductor substrate and plural surface-emitting lasers configured to emit light mutually different wavelengths, each surface-emitting laser including a lower Bragg reflector provided on the semiconductor substrate, a resonator provided on the lower Bragg reflector, an upper Bragg reflector provided on the resonator, and a wavelength adjustment layer provided in the upper Bragg reflector or lower Bragg reflector, the wavelength adjustment layers included in the surface-emitting lasers having mutually different thicknesses, at least one of the wavelength adjustment layers including adjustment layers made of two kinds of materials, and numbers of the adjustment layers included in the wavelength adjustment layers being mutually different.

Abstract: A surface emitting laser element includes plural surface emitting lasers provided on a substrate. Each of the plural surface emitting lasers includes a first reflection mirror provided on the substrate; an active layer provided on the first reflection mirror; a wavelength adjustment region provided on the active layer; and a second reflection mirror provided on the wavelength adjustment region. The wavelength adjustment region includes a phase adjustment layer and a wavelength adjustment layer provided on the phase adjustment layer. A thickness of the wavelength adjustment region is approximately an odd multiple of a wavelength of emitted light divided by four. A thickness of the phase adjustment layer is approximately an even multiple of the wavelength of the emitted light divided by four. A thickness of the wavelength adjustment layer is different from a thickness of a wavelength adjustment layer of at least one of the other surface emitting lasers.

Abstract: The present disclosure relates to a compact external cavity tunable laser apparatus. The laser apparatus includes a substrate, an external cavity tunable reflecting unit that reflects laser light entering from the outside on the substrate and selects and varies a wavelength of the reflected laser light, an optical fiber that outputs the laser light on the substrate; and an highly integrated light source that integrates the laser light input from the external cavity tunable reflecting unit using inclined input and output waveguides, a curved waveguide, and a straight waveguide to output the integrated laser light to the optical fiber in order to match an optical axis formed with the external cavity tunable reflecting unit with an optical axis formed with an optical fiber.

Abstract: A photonic-crystal surface-emitting laser (PCSEL) includes a gain medium electromagnetically coupled to a photonic crystal whose energy band structure exhibits a Dirac cone of linear dispersion at the center of the photonic crystal's Brillouin zone. This Dirac cone's vertex is called a Dirac point; because it is at the Brillouin zone center, it is called an accidental Dirac point. Tuning the photonic crystal's band structure (e.g., by changing the photonic crystal's dimensions or refractive index) to exhibit an accidental Dirac point increases the photonic crystal's mode spacing by orders of magnitudes and reduces or eliminates the photonic crystal's distributed in-plane feedback. Thus, the photonic crystal can act as a resonator that supports single-mode output from the PCSEL over a larger area than is possible with conventional PCSELs, which have quadratic band edge dispersion. Because output power generally scales with output area, this increase in output area results in higher possible output powers.

Abstract: The present invention provides a surface emitting laser that provides a sufficient optical output and is suitable as a light source intended for electrophotographic apparatuses, and a surface-emitting-laser array and an image forming apparatus each including the surface emitting laser. The surface emitting laser includes a first stepped structure on a front surface of a front mirror. In the first stepped structure, a difference L between an optical path length in a first area and an optical path length in a second area satisfies the following expression: (¼+N)?<|L|<(¾+N)? where N is an integer.

Abstract: Use of semiconductor materials having a lattice constant of within +/?1.6% of 6.1 angstroms facilitates improved semiconductor device performance and new semiconductor structures, for example integration of field-effect devices and optoelectronic devices on a single wafer. High-mobility channels are enabled, improving device performance.

Abstract: An optical semiconductor element includes: a grating base layer including a projection-recess structure disposed over a substrate; and a grating cover layer including a group III-V semiconductor having three or more elements, wherein the grating cover layer includes a first region which is disposed over recessed portions of the grating base layer and which has a compositional ratio of a group III-V semiconductor having a first refractive index, and a second region which is disposed over projecting portions of the grating base layer and which has a compositional ratio of a group III-V semiconductor having a second refractive index that is smaller than the first refractive index, wherein the grating base layer includes a group III-V semiconductor having a third refractive index that is smaller than the first refractive index.

Abstract: A surface emitting laser array element is disclosed that includes a lower distributed bragg reflector (DBR) that is formed on a substrate, an active layer that is formed on the lower DBR, and an upper DBR that is formed on the active layer. A mesa and a dummy mesa that is arranged at a periphery of the mesa are created by removing a portion of the upper DBR. The mesa forms a surface emitting laser, and a wiring is connected to an electrode that is formed on an upper face of the mesa. The wiring includes a portion that is arranged over an upper face of the dummy mesa, a side face of the dummy mesa, and a bottom face at a peripheral region of the dummy mesa extending along a longitudinal direction of the wiring.

Abstract: Provided is a multi-wavelength laser diode module including a plurality of laser diodes having different consecutive light emission wavelength regions, a plurality of filters respectively corresponding to the plurality of laser diodes, and an optical waveguide path that transmits light emitted from the plurality of laser diodes to the plurality of filters and collects light reflected or transmitted by the plurality of filters to transmit the collected light to the outside.

Abstract: An optical semiconductor device, includes: a plurality of first diffraction grating layers disposed at a spacing from each other along first direction above first semiconductor layer, length of a lower surface of each of a plurality of first diffraction gratings along first direction being longer than a length of an upper surface of first diffraction grating; second diffraction grating layer disposed along first direction above first semiconductor layer, first and second diffraction grating layers being alternately disposed at a spacing from each other, a length of an upper surface of second diffraction grating layer along first direction being longer than the length of a lower surface of second diffraction layer; a diffraction grating including first and second diffraction grating layers; a second semiconductor layer disposed between first and second diffraction grating layers and under second diffraction grating layer; and third semiconductor layer disposed on first and second diffraction grating layers.

Abstract: Techniques and devices for using a chirped fiber Bragg grating to compress amplified laser pulses.

Abstract: A laser device (100) includes a laser (110; 210; 310; 410; 510) in turn including at least one Distributed Bragg Reflector (DBR) section (111), at least one phase section (112) and at least one gain section (113), further including a laser control element (150), a feedback control element (140) and a frequency noise discriminator (130,131), which feedback control element is arranged to feed a variable feedback signal to at least one of the at least one DBR section and the at least one phase section of the laser, so that the output laser frequency is altered in response to a variation in the feedback signal or the combination of respective feedback signals, whereby the feedback signal or combination of respective feedback signals is varied as a function of the detected frequency fluctuation so as to counteract the detected frequency fluctuation.

Abstract: A cable television transmitter includes a substrate including a silicon material, control electronics disposed in the substrate, and a gain medium coupled to the substrate. The gain medium includes a compound semiconductor material. The cable television transmitter also includes an optical modulator optically coupled to the gain medium and electrically coupled to the control electronics, a waveguide disposed in the substrate and optically coupled to the gain medium, a first wavelength selective element characterized by a first reflectance spectrum and disposed in the substrate, and a second wavelength selective element characterized by a second reflectance spectrum and disposed in the substrate. The cable television transmitter further includes an optical coupler disposed in the substrate and joining the first wavelength selective element, the second wavelength selective element, and the waveguide and an output mirror.

Abstract: A wavelength-tunable light source includes light sources having differing variable wavelength regions, where light sources having adjacent wavelength regions are distributed to different systems. The light sources are each set such that an end portion of the variable wavelength region of the light source overlaps an end portion of the variable wavelength region of another light source. A control unit selects and drives a first light source of a first system, varies a wavelength of the first light source, selects a second light source that is of a second system among the different systems and that has a wavelength region overlapping the variable wavelength region of the first light source, drives the second light source concurrently with the first light source and subsequently switches to the output light of the second light source, causing wavelength variation and executing continuous wavelength variation over a wide range.

Abstract: Provided is a vertical light emitting device comprising an upper multilayer reflective film and a lower multilayer reflective film that are formed facing each other and oscillate light; an intermediate layer that is formed below the upper multilayer reflective film and includes a layer having a different composition than the upper multilayer reflective film; and an electrode portion that is formed to sandwich the intermediate layer in a cross-sectional plane parallel to an oscillation direction of the light and to have a top end that is higher than a top surface of the intermediate layer. After the electrode portion is formed to sandwich the intermediate layer, the upper multilayer reflective film is layered on the intermediate layer.

Abstract: A spatially modulated waveguide Bragg grating mirror is suspended over a substrate by plurality of fingers extending laterally away from the waveguide centerline. The positions of the fingers are coordinated with the positions of crests and valleys of amplitude or phase modulation of the Bragg grating, to avoid disturbing the Bragg grating when it is tuned by heating. When the Bragg grating is heated, the heat flows through the fingers creating a quasi-periodic refractive index variation along the Bragg grating due to quasi-periodic temperature variation created by the heat flow from the grating through the supporting fingers. Due to coordination of the positions of supporting fingers with positions of the crests and valleys of modulation, the optical phase coherence is maintained along the Bragg grating, so that the spectral lineshape or filtering property of the Bragg grating is substantially preserved.

Abstract: A photonic crystal surface emitting laser array reduces the occurrence of reflected feedback light while also reducing input of leaking light. The photonic crystal surface emitting laser array includes a plurality of first photonic crystal regions that cause laser oscillation, a second photonic crystal region that causes light diffraction to occur in an out-of-plane direction, and a light absorber that is provided above the second photonic crystal region and that absorbs light having a wavelength ?. A radiation coefficient of each first photonic crystal region is smaller than a radiation coefficient of the second photonic crystal region.

Abstract: The protective film that covers the top distributed Bragg reflecting mirror has a central region and a peripheral region. The central region has a protrusion that projects relative to the peripheral region in a direction in which the laser light is emitted. The VCSEL satisfies relations below: dp×n=(N/2)×?, and dc×n=dp×n+(1/4+M/2)×?, where ? is a wavelength of the laser light in vacuum; dc is a film thickness of the protective film in the central region; dp is a film thickness of the protective film in the peripheral region; n is a refractive index of the protective film (wherein a refractive index of air<the refractive index n of the protective film<a refractive index of the top distributed Bragg reflecting mirror); and N is a natural number.

Abstract: An optical device includes an active layer disposed over a semiconductor substrate, a diffraction grating disposed over the active layer, a clad layer partly disposed over the diffraction grating, at least one first burying material layer disposed beside side surfaces of end portions of the clad layer over the diffraction grating, and at least one second burying material layer disposed beside side surfaces of a center portion of the clad layer over the diffraction grating. A refractive index of the at least one first burying material layer is different from a refractive index of the at least are second burying material layer.

Abstract: A surface emitting semiconductor laser includes a first semiconductor multilayer reflector of a first conductivity type, an active area, a second semiconductor multilayer reflector of a second conductivity type, a current confinement layer having a conductive area and a surrounding high-resistance area, each provided on a substrate, and a higher-order transverse mode suppressing layer formed on an emission surface from which laser light is emitted and in an area in which higher-order transverse mode is induced. The higher-order transverse mode suppressing layer includes first to third insulation films having first to third refractive indices, respectively, formed on each other, and capable of transmitting an oscillation wavelength. The second refractive index is lower than the first refractive index. The third refractive index is higher than the second refractive index. The optical film thickness of the first to third insulation films is an odd number times one-fourth of the oscillation wavelength.

Abstract: Embodiments of the invention describe an illuminator having a light source to originate an illumination beam, wherein the light source further comprises a set of vertical-cavity surface emitting lasers (VCSELs), including a first VCSEL having a first laser emission wavelength, and a second VCSEL having a second laser emission wavelength different than the first laser emission wavelength. Thus, by varying laser emission wavelengths of VCSELs in a VCSEL array, embodiments of the invention produce low-contrast speckle, and do not limit the imaging capabilities of the host illumination system. In some embodiments of the invention, vertical external cavity surface emitting lasers (VECSELs) are utilized to produce the above described varying laser emission wavelengths.

Abstract: Two or more first reflectors are formed on a substrate. Each of the first reflectors reflects the light input to its input port and returns it there, while exhibiting a reflection spectrum featuring a peak at the target wavelength. A first optical coupler is formed on the substrate to divide the light output from an optical amplifier and output the divided lights to the input ports of the two or more first reflectors, as well as combining the reflected lights from the first reflector and re-inputting the combined light to the optical amplifier. Each of the first reflectors contains a ring resonator of the same size, and the delay for the light input to the input port of a first reflector to return there after being reflected is the same for all first reflectors.

Abstract: Implementing a layered hyperbolic metamaterial in a vertical cavity surface emitting laser (VCSEL) to improve thermal conductivity and thermal dissipation thereby stabilizing optical performance. Improvement in the thermal management and power is expected by replacing the distributed Bragg reflector (DBR) mirrors in the VCSEL. The layered metamaterial structure performs the dual function of the DBR and the heat spreader at the same time.

Abstract: The thermal processing device includes a stage, a continuous wave electromagnetic radiation source, a series of lenses, a translation mechanism, a detection module, a three-dimensional auto-focus, and a computer system. The stage is configured to receive a substrate thereon. The continuous wave electromagnetic radiation source is disposed adjacent the stage, and is configured to emit continuous wave electromagnetic radiation along a path towards the substrate. The series of lenses is disposed between the continuous wave electromagnetic radiation source and the stage, and are configured to condense the continuous wave electromagnetic radiation into a line of continuous wave electromagnetic radiation on a surface of the substrate. The translation mechanism is configured to translate the stage and the line of continuous wave electromagnetic radiation relative to one another. The detection module is positioned within the path, and is configured to detect continuous wave electromagnetic radiation.

Abstract: A semiconductor laser has a first diffractive grating area. The first diffractive grating area has a plurality of segments. Each segment has a first area including a diffractive grating and a second area that is space area combined to the first area. Optical lengths of at least two of the second areas are different from each other. A refractive-index of each of the segments are changeable.

Abstract: A composite light source includes a substrate having a top surface, and a first vertical light source formed in the substrate. The first light source includes least a lower mirror, a first active region above the lower mirror, wherein the first active region has a thickness sufficient when electrically pumped to emit predominantly a spontaneous vertical emission from the first active region towards the top surface having an angular range of at least (?) 30°. A second light source is formed in the substrate above the first active region including a second active region. The spontaneous vertical emission is at a first wavelength ?1 that optically drives said second active region to provide an emission at a second wavelength ?2, wherein ?2>?1.

Abstract: A surface-emission laser device comprises an active layer, cavity spacer layers provided at both sides of the active layer, reflection layers provided at respective sides of the cavity spacer layers, the reflection layers reflecting an oscillation light oscillated in the active layer and a selective oxidation layer. The selective oxidation layer is provided between a location in the reflection layer corresponding to a fourth period node of the standing wave distribution of the electric field of the oscillating light and a location in the reflection layer adjacent to the foregoing fourth period node in the direction away from the active layer and corresponding to an anti-node of the standing wave distribution of the electric field of the oscillation light.

Abstract: A the vertical-cavity surface-emitting laser includes a stripe-shaped active medium (10) having an emission maximum at a first wavelength (?1), wherein a first reflector (18) is arranged below the stripe-shaped active medium (10) and a second reflector (20) is arranged above the stripe-shaped active medium (10), with the first reflector (18) facing the second reflector (20), wherein the first reflector (18) and a second reflector (20) have a reflectivity maximum in the region of the first wavelength (?1), wherein a third reflector (12) and a fourth reflector (13) are each arranged on a side above or next to the stripe-shaped active medium (10), wherein the third reflector (12) faces the fourth reflector (13), and wherein the third reflector (12) and the fourth reflector (13) have a reflectivity maximum in the region of a second wavelength (?2), wherein the first wavelength (?1) is greater than the second wavelength (?2).

Abstract: A multi-wavelength laser array of a plurality of emitters in a diode bar or stack where each beam is deflected by a different angle to be incident upon a uniform volume holographic grating with a portion of the beam being deflected as a feedback portion while a further portion provides a wavelength tuned output unique to each emitter. The arrangement of a uniform volume holographic grating with deflectors such as phaseplates eliminates the need to use expensive wavelength chirped gratings.

Abstract: A surface-emitting laser that can prevent delamination at the interface of a selective oxidation layer and a spacer layer, while suppressing any rise of voltage, to improve the reliability of operation.

Abstract: A combined laser light source includes a substrate, a waveguide, a first laser source, a second laser source, and a Bragg grating. The substrate includes a top surface, a first side surface, and a second side surface. The waveguide is formed in the top surface and includes a first branch and a second branch connecting with the first branch. The first laser source connects with an entrance of the first entrance and emits a first laser beam into the first branch. The second laser source connects with an entrance of the second entrance and emits a second laser beam into the second branch. The Bragg grating is formed at an interaction of the first branch and the second branch and is configured to reflect the second laser beam into the first branch.