Abstract: [Object] To provide a technology capable of appropriately determining whether overcurrent has flowed in a light emitting element even in a case where the light emitting element is driven by the pulse driving method. [Solving Means] An overcurrent determination circuit according to the present technology includes: a sample-and-hold circuit that obtains a driving current value of a light emitting element in accordance with a timing of a light emitting interval of the light emitting element that emits pulsed light; and a comparator circuit that compares the obtained driving current value with a value of a predetermined determination level and determines whether overcurrent has flowed in the light emitting element.

Abstract: The invention relates to a laser device (100) comprising a substrate (10), on the surface of which an optical waveguide (11) is arranged, which has an optical resonator (12, 13) with such a resonator length that at least one resonator mode forms a stationary wave in the resonator (12, 13), and an amplification medium that is arranged on a surface of the optical waveguide (11), wherein the amplification medium comprises a photonic crystal (20) having a plurality of column- and/or wall-shaped semiconductor elements (21) which are arranged periodically on the surface of the optical waveguide (11) while protruding from the optical waveguide (11), and wherein the photonic crystal (20) is designed to optically interact with the at least one resonator mode of the optical resonator (12, 13) and to amplify light having a wavelength of the at least one resonator mode of the optical resonator (12, 13). The invention also relates to methods for the operation and production of the laser device.

Abstract: Various implementations disclosed herein relate to an integrated laser driver circuit for switching a pulse current (IP) for a laser diode having a plurality of sub-switching units for generating in each case a partial current (IT) using a switch for pulsing the partial current (IT), wherein the sub-switching units are connected to one another in parallel for generating the pulse current (IP), wherein an energy accumulator is integrated into each of the sub-switching units to provide the switching energy required for switching the switch. The disclosure further relates to a laser system having a laser diode and an integrated laser driver circuit.

Abstract: The present invention discloses a transverse mode switchable all-fiber high-order mode Brillouin laser. The laser comprises a narrow linewidth pump laser, an optical amplifier, a 1×N optical switch (N?2), a fiber mode selection coupler group, a first polarization controller, a fiber circulator, a fiber coupler, a second polarization controller, and a few-mode fiber. Based on the Brillouin nonlinear gain of a few-mode fiber in a ring cavity, the present invention realizes the resonance amplification of a specific order transverse mode in the cavity, and obtains the transverse mode switchable high-order mode laser beam output. The present invention, adopting an all-fiber structure, has the advantages of simple structure, low cost, easy fiber system integration, high stability and narrow linewidth of outputted laser beams, etc., and improves the practicality and reliability of high-order mode lasers.

Abstract: There are provided high power, high brightness solid-state laser systems that maintain initial beam properties, including power levels, and do not have degradation of performance or beam quality, for at least 10,000 hours of operation. There are provided high power, high brightness solid-state laser systems containing Oxygen in their internal environments and which are free from siloxanes.

Abstract: An optical module includes: a stem including a first surface and a second surface opposite to the first surface; a thermoelectric cooler including a heat-releasing substrate fixed to the first surface; a semiconductor laser element attached to the thermoelectric cooler; a cap fixed to the first surface and covering the thermoelectric cooler and the semiconductor laser element; a lens fixed to the cap; and a restriction body fixed to the second surface. The linear thermal expansion coefficients of the heat-releasing substrate and the restriction body are smaller than the linear thermal expansion coefficient of the stem.

Abstract: An optical sub-assembly includes a diode submount structure, a diode mounted to the diode submount, and a thermoelectric cooler (TEC). The TEC is in thermal contact with the diode, and the diode is positioned between the diode submount structure and the TEC.

Abstract: The present embodiment relates to a single semiconductor light-emitting element including a plurality of light-emitting portions each of which is capable of generating light of a desired beam projection pattern and a method for manufacturing the semiconductor light-emitting element. In the semiconductor light-emitting element, an active layer and a phase modulation layer are formed on a common substrate layer, and the phase modulation layer includes at least a plurality of phase modulation regions arranged along the common substrate layer. The plurality of phase modulation regions are obtained by separating the phase modulation layer into a plurality of places after manufacturing the phase modulation layer, and as a result, the semiconductor light-emitting element provided with a plurality of light-emitting portions that have been accurately aligned can be obtained through a simple manufacturing process as compared with the related art.

Abstract: A laser structure including a Si or Ge substrate, a III-V buffer layer formed on the substrate, a light emitting diode (LED) formed on the buffer layer configured to produce visible light, a lens disposed on the LED to focus light from the LED, a photonic crystal layer formed on the LED to receive the light focused by the lens, and a monolayer semiconductor nanocavity laser formed on the photonic crystal layer for receiving light through the photonic crystal layer from the LED. The LED and the laser are formed monolithically and the LED acts as an optical pump for the laser.

Abstract: A laser diode chip has a laser facet, which includes a coating. The coating includes an inorganic layer and an organic layer. In one example, the coating has a number of inorganic layers, including a heat-conductive layer. For example, the inorganic layers may form a reflection-increasing or reflection-decreasing layer sequence.

Abstract: An OLED (Organic Light Emitting Diode) device can include a red emission layer, a green emission layer, and a blue emission layer which are non-patterned and stacked as common layers configured such that a thickness of each of a hole transporting layer, the red emission layer, the green emission layer, and the blue emission layer is respectively less than those corresponding layers in a conventional OLED device having a red emission layer, a green emission layer, and a blue emission layer which are patterned.

Abstract: The present embodiment relates to a single semiconductor light-emitting element including a plurality of light-emitting portions each of which is capable of generating light of a desired beam projection pattern and a method for manufacturing the semiconductor light-emitting element. In the semiconductor light-emitting element, an active layer and a phase modulation layer are formed on a common substrate layer, and the phase modulation layer includes at least a plurality of phase modulation regions arranged along the common substrate layer. The plurality of phase modulation regions are obtained by separating the phase modulation layer into a plurality of places after manufacturing the phase modulation layer, and as a result, the semiconductor light-emitting element provided with a plurality of light-emitting portions that have been accurately aligned can be obtained through a simple manufacturing process as compared with the related art.

Abstract: A substrate treatment method of treating a substrate using a block copolymer containing a hydrophilic polymer and a hydrophobic polymer, includes: a resist pattern formation step of forming a predetermined resist pattern by a resist film on the substrate; a thin film formation step of forming a thin film for suppressing deformation of the resist pattern on a surface of the resist pattern; a block copolymer coating step of applying a block copolymer to the substrate after the formation of the thin film; and a polymer separation step of phase-separating the block copolymer into the hydrophilic polymer and the hydrophobic polymer.

Abstract: A laser-based light source includes a laser device configured to generate laser light of a predetermined laser wavelength and emit this laser light as a laser beam. A light-conversion device is configured to convert at least part of the laser light into converted light and a laser-output sensor is configured to determine a laser-output signal proportional to the output of laser light emitted by the laser device. Further, a converted-light sensor is configured to determine a converted-light signal proportional to the output of converted light emitted by the light-conversion device. A controller is configured to receive the laser-output signal and the converted-light signal, to determine a safe-to-operate parameter, based on the laser-output signal and the converted-light signal, and to control the operation of the laser-based light source based on a comparison of the safe-to-operate parameter with a at least one predefined threshold.

Abstract: An optoelectronic apparatus, such as a photodetector apparatus comprising a substrate (1), a dielectric layer (2), a transport layer, and a photosensitizing layer (5). The transport layer comprises at least a 2-dimensional semiconductor layer (3), such as MoS2, and the photosensitizing layer (5) comprises colloidal quantum dots. Enhanced responsivity and extended spectral coverage are achieved with the disclosed structures.

Abstract: Provided is a thermoelectric cooler built-in stem, including a first stem member on a top face of which a temperature controlled target device such as an optical module or the like is mounted, a second stem member which opposes to the first stem member each other, and a thermoelectric cooler being sandwiched between the first stem member and the second stem member, for controlling the temperature controlled target device, whereby a space between the first stem member and the second stem member is filled by an insulating resin whose thermal conductivity is low.

Abstract: A method for manufacturing an optical element is a method for manufacturing an optical element in which laser light is transmitted, reciprocated, or reflected, and the method includes a first step of obtaining a bonded element formed by subjecting a first element part and a second element part, both being transparent to laser light, to surface activated bonding with a non-crystalline layer interposed therebetween; and after the first step, a second step of crystallizing at least a portion of the non-crystalline layer by raising the temperature of the bonded element. In the second step, the temperature of the bonded element is raised to a predetermined temperature that is lower than the melting points of the first element part and the second element part.

Abstract: A novel stacked structure that is highly convenient or reliable is provided. A method for manufacturing a novel stacked structure that is highly convenient or reliable is also provided. Furthermore, a novel semiconductor device is provided. The stacked structure includes first to fifth regions in this order. Each of the first to fifth regions includes a first base and a second base. The first region, the third region, and the fifth region each include a spacer that makes a predetermined distance between the first base and the second base.

Abstract: The invention relates to a discoidal or cuboidal solid body for a laser amplification system of a solid-state laser, which solid body contains at least one laser-active material, has an upper side defining an upper side plane and a lower side defining a lower side plane, wherein the upper side plane and the lower side plane are inclined in relation to each other and enclose an angle of inclination, wherein the lower side is provided with a first reflective coating, wherein the upper side is provided with a second reflective coating, and wherein at least one of the upper side and the lower side has at least one optical input coupling opening for input coupling at least one of a seed laser radiation field and a pump laser radiation field into the solid body between the first and the second reflective coating.

Abstract: A wavelength beam combining device includes: a light source unit comprising a plurality of laser light sources, each being configured to emit a laser beam with a predetermined wavelength width; a light condensing member configured to condense the laser beams emitted from the light source unit; a diffraction grating on which the laser beams condensed by the light condensing member are incident; a resonator mirror disposed in an optical path of a diffracted beam from the diffraction grating; and an output control unit configured to turn off, among the plurality of laser light sources, at least laser light sources located farthest from an optical axis of the light condensing member, to reduce an output of the wavelength beam combining device relative to an output of the wavelength beam combining device when all the plurality of laser light sources are turned on.