Abstract: In some implementations, a vertical cavity surface emitting laser (VCSEL) includes a substrate layer and epitaxial layers on the substrate layer. The epitaxial layers may include an active layer, a first mirror, a second mirror, and one or more oxidation layers. The active layer may be between the first mirror and the second mirror, and the one or more oxidation layers may be proximate to the active layer. The one or more oxidation layers may be configured to control beam divergence of a laser beam emitted by the VCSEL based on at least one of: a quantity of the one or more oxidation layers, a shape of the one or more oxidation layers, a thickness of the one or more oxidation layers, or a proximity of the one or more oxidation layers to the active layer.

Abstract: A gas laser apparatus may include: a laser chamber connected through a first control valve to a first laser gas supply source that supplies a first laser gas containing a halogen gas; a purification column that removes at least a part of the halogen gas and a halogen compound from at least a part of a gas exhausted from the laser chamber; a booster pump; and a controller that calculates, on a basis of a first amount of a gas supplied from the booster pump to the laser chamber, a second amount of the first laser gas that is to be supplied to the laser chamber and controls the first control valve on a basis of a result of the calculation of the second amount.

Abstract: A laser system's laser light energy control and resulting dose control is improved by creating and using a set of gain estimators, one for each of a set or range of laser light pulse repetition rates. When a new repetition rate is used, its corresponding gain estimator is retrieved, used to compute the voltage to fire the laser source, and updated. The resulting generated laser light thereby avoids the convergence delay inherent in prior laser systems and, further, can repeatedly do so with subsequent specified repetition rates.

Abstract: An optical transmitter module includes optical semiconductor devices including a first optical semiconductor device, a temperature adjustment means for collectively performing temperature adjustment on the optical semiconductor devices, and a first thermal resistor that is disposed between the first optical semiconductor device and the temperature adjustment means, in which, when the temperature adjustment means is driven, the temperature of the first optical semiconductor device is higher than temperatures of other optical semiconductor devices which are different from the first optical semiconductor device.

Abstract: A low voltage laser device having an active region configured for one or more selected wavelengths of light emissions.

Abstract: Disclosed herein are multi-layered optically active regions for semiconductor light-emitting devices (LEDs) that incorporate intermediate carrier blocking layers, the intermediate carrier blocking layers having design parameters for compositions and doping levels selected to provide efficient control over the carrier injection distribution across the active regions to achieve desired device injection characteristics. Examples of embodiments discussed herein include, among others: a multiple-quantum-well variable-color LED operating in visible optical range with full coverage of RGB gamut, a multiple-quantum-well variable-color LED operating in visible optical range with an extended color gamut beyond standard RGB gamut, a multiple-quantum-well light-white emitting LED with variable color temperature, and a multiple-quantum-well LED with uniformly populated active layers.

Abstract: A solid-state laser device includes an inner container, an outer container, a cooling medium supply unit, and a cover section. The inner container in which a laser medium is accommodated includes an inner light-transmitting unit. An outer light-transmitting unit of the outer container is provided at a part that faces the inner light-transmitting unit and is vacuum-insulated from the inner light-transmitting unit. The cooling medium supply unit supplies a cooling medium so that the cooling medium comes in contact with a surface other than a light input and output surface in the laser medium. The cover section partitions a light-passing area from a cooling medium supply area to which the cooling medium is supplied.

Abstract: An embodiment provides a beam projector module that includes: a light source configured to output light; a substrate configured to support the light source; an optical device configured to reduce the light in terms of intensity output to a predetermined space; a frame configured to space the optical device apart from the light source by a predetermined distance, the frame forming a closed space with the substrate and the optical device; a temperature sensor configured to measure a temperature of the frame; and a processor configured to control an output of the light source. The processor is configured to operate the light source in an eye-safety mode when a temperature drop rate of the frame exceeds a reference value.

Abstract: A laser device has a photonic crystal surface emitting laser (PCSEL) element. At a first lateral side of the PCSEL element, a reflector is arranged to reflect back into the PCSEL element at least a portion of light travelling out of the PCSEL element through the first lateral side of the PCSEL element. Between the first lateral side of the PCSEL element and the reflector there is interposed an electrically controllable light-transmission region configured to control the transmission of light from the PCSEL element to the reflector, based on an electrical input. Also disclosed is a method of operation of a corresponding laser device.

Abstract: In an ultrastable laser, using a large mode-volume optical resonator, which suppresses the resonator's fast thermal fluctuations, together with the stimulated Brillouin scattering (SBS) optical nonlinearity presents a powerful combination that enables the ability to lase with an ultra-narrow linewidth of 20 Hz. The laser's long-term temperature drift is compensated by using the narrow Brillouin line to sense minute changes in the resonator's temperature (e.g., changes of 85 nK). The precision of this temperature measurement enables the stabilization of resonators against environmental perturbations.

Abstract: A method of treating an ischemic event in tissue of a subject in need thereof, includes applying light to a tissue susceptible to ischemic reperfusion injury, the light having a wavelength selected from two wavelength ranges selected from 730-770 nm, 850-890 nm, 880-920 nm, and 930-970 nm, thereby to reduce ischemic reperfusion injury in the tissue of the subject.

Abstract: A nanolaser includes a silicon substrate and a III-V layer formed on the silicon substrate having a defect density due to differences in materials. A laser region is formed on or in the III-V layer, the laser region having a size based upon the defect density.

Abstract: Embodiments provide for selective-area growth of III-V materials for integration with silicon photonics. The resulting platform includes a substrate; an insulator, extending a first distance from the substrate, including a passive optical component at a second distance from the substrate less than the first distance, and defining a pit extending to the substrate; and a III-V component, extending from the substrate within in the pit defined in the insulator, the III-V component including a gain medium included at the second distance from the substrate and optically coupled with the passive optical component. The pit may define an Optical Coupling Interface between the III-V component and the passive optical component, or a slit defined between the III-V component and the passive optical component may define the Optical Coupling Interface.

Abstract: A radio-frequency, RF, slab laser 10 with a Z-fold resonator cavity defined by an output mirror 32, a first fold mirror 34, a second fold mirror 36 and a rear mirror 30. The second fold mirror 36 is rotated by an adjustment angle away from the angle it would have if the mirrors were all plane mirrors and directed the round trip beam path by direct reflection. Moreover, the rear mirror 30 is rotated by an adjustment angle that is approximately twice the adjustment angle of the second fold mirror 36. These rotations of the rear mirror 30 and second fold mirror 36 suppresses parasitic mode paths that would otherwise exist.

Abstract: An ultrafast electro-optic laser makes a stabilized comb and includes: a comb generator that produces a frequency comb; a dielectric resonant oscillator; a phase modulator in communication with the dielectric resonant oscillator; an intensity modulator in communication with the phase modulator; an optical tailor in communication with the comb generator and that produces tailored light; a filter cavity in communication with the intensity modulator; a pulse shaper in communication with the filter cavity; a highly nonlinear fiber and compressor in communication with the pulse shaper; an interferometer in communication with the optical tailor and that produces a difference frequency from the tailored light; and an electrical stabilizer in communication with the interferometer and the comb generator and that produces the stabilization signal with a stabilized local oscillator cavity that produces a stabilized local oscillator signal that is converted into the stabilization signal and communicated to the dielectric

Abstract: Systems and methods are described herein to grow a layered structure. The layered structure comprises a first germanium substrate layer having a first lattice constant, a second layer that has a second lattice constant and is epitaxially grown over the first germanium substrate layer, wherein the second layer has a composite of a first constituent and a second constituent, and has a first ratio between the first constituent and the second constituent, and a third layer that has a third lattice constant and is epitaxially grown over the second layer, wherein the third layer has a composite of a third constituent and a fourth constituent, and has a second ratio between the third constituent and the fourth constituent, wherein the first ratio and the second ratio are selected such that the first lattice constant is between the second lattice constant and the third lattice constant.

Abstract: A light source device includes a laser diode configured to emit a laser light used as an illumination light, a determination unit configured to determine one of a plurality of modes as an operation mode of the laser diode based on usage state of the light source device; and a driver configured to drive the laser diode in a condition that a bias current to the laser diode is applied depending on the operation mode determined by the determination unit.

Abstract: A laser system has a fiber cable, a pump enclosure connected to the fiber cable outside of the pump enclosure, and a laser-head enclosure connected to the fiber cable disposed outside of the laser-head enclosure. The pump enclosure houses a fiber-coupled laser diode configured to produce and convey pump light through the pump enclosure out to the fiber cable. The laser-head enclosure houses a crystal. The pump light, when produced by the laser diode, propagates out from the pump enclosure through the fiber cable into the laser-head enclosure and into the crystal. The crystal produces a laser beam in response to the pump light. The integrated fiber of the laser diode, the fiber cable, and internal fiber of the laser-head enclosure, through which the pump light propagates, may be single-mode fibers, to achieve superior laser system performance with lower frequency and intensity noise than pumping through multimode fibers.

Abstract: In an embodiment, a device includes: a first reflective structure including first doped layers of a semiconductive material, alternating ones of the first doped layers being doped with a p-type dopant; a second reflective structure including second doped layers of the semiconductive material, alternating ones of the second doped layers being doped with a n-type dopant; an emitting semiconductor region disposed between the first reflective structure and the second reflective structure; a contact pad on the second reflective structure, a work function of the contact pad being less than a work function of the second reflective structure; a bonding layer on the contact pad, a work function of the bonding layer being greater than the work function of the second reflective structure; and a conductive connector on the bonding layer.

Abstract: A package structure includes a carrier, a housing, an edge-emitting laser, first and second reflective members and a diffractive optical element. The housing disposed on a mounting surface of the carrier has a receiving space and a top surface, which has an opening and a center line perpendicular to the top surface and the mounting surface. The edge-emitting laser disposed in the receiving space and on the mounting surface has a light-emitting surface emitting a laser beam. The first reflective member is disposed in the receiving space and spaced apart from the light-emitting surface. The second reflective member is disposed in the receiving space and located on the center line above the edge-emitting laser. The diffractive optical element is disposed on the top surface. The laser beam reflected by the first and second reflective members passes through the diffractive optical element to emit out of the housing.