Abstract: An optical device according to an embodiment includes a laser light source, a first optical waveguide that propagates light being output from the laser light source, a first distribution device that distribute the light into n lights, n second optical waveguides that propagates the n lights being output from the first distribution device, n second distribution devices that distribute each of the n lights into m lights, n×m third optical waveguides arranged in a matrix form and propagates the n×m lights being output from the m second distribution devices, a control electrode that apply a voltage or current to each of the third optical waveguides, and control phase of the light propagating through the third optical waveguides, and an output end surface that output the n×m lights.

Abstract: An internal-combustion engine includes a cylinder, a piston, a spark plug, and a fuel injection device. The piston includes a top surface, a guiding protrusion, and a cavity. The cavity is provided at a position closer to the fuel injection device than the guiding protrusion when viewed from above the top surface of the piston. The guiding protrusion includes a guiding surface to guide the fuel mist toward the spark plug when the fuel mist is injected from the fuel injection device at a first predetermined timing in a compression stroke. The cavity includes a guiding wall portion to guide the fuel mist toward the spark plug when the fuel mist is injected from the fuel injection device at a timing in the compression stroke between the first predetermined timing and a second predetermined timing.

Abstract: A liquid level detector may include a float; an arm attached to the float and configured to convert a linear motion of the float in an up-and-down direction to a rotary motion; a sensor configured to detect the rotary motion; and a supporting member supporting the arm to be rotatable relative to the sensor. The supporting member may include: a body fixed to the sensor; a holder rotatably attached to the body; and a cover arranged on an opposite side from the body with the holder intervened in between, and covering the holder from the opposite side. The arm may be supported by the supporting member between the holder and the cover.

Abstract: A liquid level detector may comprise an arm attached to a float, a holder fixed to the arm, and a body rotatably supporting the holder. The body may comprise a first rotation regulator and a second rotation regulator. The first rotation regulator may regulate a rotation angle range of the arm to a first range. The second rotation regulator may regulate the rotation angle range of the arm to a second range. The first range and the second range may not overlap each other in a rotation direction of the arm. Each of the plurality of rotation regulators may comprise a pair of stoppers disposed separately from each other in the rotation direction of the arm. At least a part of area between the pair of stoppers of the each of the plurality of rotation regulators may be open to outside of the body.

Abstract: A semiconductor laser device in an embodiment includes a compound semiconductor layer and a silicon layer. The compound semiconductor layer includes an active layer emitting laser light and has a first mesa structure. The silicon layer is bonded with the compound semiconductor layer. A diffraction grating is provided on a surface of the silicon layer which faces the compound semiconductor layer, and includes a main diffraction grating and two sub-diffraction gratings. The main diffraction grating extends in a longitudinal direction of the first mesa structure; the sub-diffraction gratings are disposed on both sides of the main diffraction grating.

Abstract: An optical device according to an embodiment includes a laser light source, a first optical waveguide that propagates light being output from the laser light source, a first distribution device that distribute the light into n lights, n second optical waveguides that propagates the n lights being output from the first distribution device, n second distribution devices that distribute each of the n lights into m lights, n×m third optical waveguides arranged in a matrix form and propagates the n×m lights being output from the m second distribution devices, a control electrode that apply a voltage or current to each of the third optical waveguides, and control phase of the light propagating through the third optical waveguides, and an output end surface that output the n×m lights.

Abstract: A specimen rack can be used for specimen containers irrespective of kinds thereof and irrespective of whether or not the specimen containers are rotated. An adapter is used for an automatic analyzer and a specimen pre-processing device and is adapted for a specimen rack capable of holding specimen containers. The adapter is provided with a specimen rack mounting section inserted and fixed to an adapter insertion section of a specimen rack body, a specimen container positioning section for holding the specimen containers, and a sleeve.

Abstract: An optical modulation device of an embodiment includes: a first p-type semiconductor region; a first n-type semiconductor region; a first low-impurity-density semiconductor region formed between the first p-type semiconductor region and the first n-type semiconductor region; a second n-type semiconductor region formed on an outer side of the first p-type semiconductor region via a second low-impurity-density semiconductor region; and a second p-type semiconductor region formed on an outer side of the first n-type semiconductor region via a third low-impurity-density semiconductor region. The carrier density in the first low-impurity-density semiconductor region is changed by current injection. The phase of light propagated through an optical waveguide structure that includes at least part of the first low-impurity-density semiconductor region is modulated.

Abstract: An athermal ring optical modulator includes a first clad layer, a ring optical resonator, a second clad layer, an input-output optical waveguide, a first conduction type region, and a second conduction type region. The ring optical resonator has a rib optical waveguide with a convex portion formed on a semiconductor slab layer. The semiconductor slab layer is formed on the first clad layer. The second clad layer covers an upper side of the rib optical waveguide. The input-output optical waveguide couples optically with the ring optical resonator. The first and second conduction type regions are formed in the semiconductor slab layer inside and outside the ring optical resonator, respectively. In addition, the second clad layer includes a material having a negative thermo-optical coefficient. The semiconductor slab layer outside the convex portion is thinner than the semiconductor slab layer inside the convex portion.

Abstract: A semiconductor laser of an embodiment includes: an optical resonator having a first cladding layer, a ring-shaped active layer on the first cladding layer, a ring-shaped second cladding layer on the active layer, a first electrode inside the ring shape on the first cladding layer, a ring-shaped second electrode on the second cladding layer, a first insulating layer between the first cladding layer and the active layer, formed from an inside wall toward an outside wall of the ring shape, where an outside wall side edge thereof is on an inner side than the outside wall, and a second insulating layer between the active layer and the second cladding layer, formed from the inside wall toward the outside wall, where an outside wall side edge thereof is on an inner side than the outside wall; and an optical waveguide optically coupled to the optical resonator.

Abstract: A semiconductor laser of an embodiment includes: an optical resonator having a first cladding layer, a ring-shaped active layer on the first cladding layer, a ring-shaped second cladding layer on the active layer, a first electrode inside the ring shape on the first cladding layer, a ring-shaped second electrode on the second cladding layer, a first insulating layer between the first cladding layer and the active layer, formed from an inside wall toward an outside wall of the ring shape, where an outside wall side edge thereof is on an inner side than the outside wall, and a second insulating layer between the active layer and the second cladding layer, formed from the inside wall toward the outside wall, where an outside wall side edge thereof is on an inner side than the outside wall; and an optical waveguide optically coupled to the optical resonator.

Abstract: An athermal ring optical modulator includes a first clad layer, a ring optical resonator, a second clad layer, an input-output optical waveguide, a first conduction type region, and a second conduction type region. The ring optical resonator has a rib optical waveguide with a convex portion formed on a semiconductor slab layer. The semiconductor slab layer is formed on the first clad layer. The second clad layer covers an upper side of the rib optical waveguide. The input-output optical waveguide couples optically with the ring optical resonator. The first and second conduction type regions are formed in the semiconductor slab layer inside and outside the ring optical resonator, respectively. In addition, the second clad layer includes a material having a negative thermo-optical coefficient. The semiconductor slab layer outside the convex portion is thinner than the semiconductor slab layer inside the convex portion.

Abstract: Provided is an optical device that includes a ring-shaped optical waveguide and an input/output optical waveguide, and that changes a resonant wavelength of the ring-shaped optical waveguide, in which the ring-shaped optical waveguide includes in part a refractive index control section for controlling a refractive index at a guided wavelength, and the refractive index control section is formed of an optical material having a thermo-optic effect with its sign different from that of an optical material that forms a section of the ring-shaped optical waveguide other than the refractive index control section.

Abstract: A power transmission device is installed in a vehicle and connected to a power generation source that is capable of outputting power for driving. The power transmission device includes a belt-type continuously variable transmission; a working fluid accumulation portion; a friction engagement element; a first pump; a pressure regulating valve; a friction engagement element pressure regulating valve; a second pump; and a switching valve.

Abstract: The overall material constant of a composite material is computed where the composite material includes multiple kinds of material components in a matrix phase, each of the material constants of the material components and the matrix phase being known. First, for the composite material, an equation, having the material constant of a virtual composite material as an unknown, is prepared by defining the virtual composite material in which each of the material components is dispersed in a form of spherical particles in the matrix phase at a known volume fractions. Next, the overall material constant of the virtual composite material is found as the overall material constant of the composite material by solving the equation. In this case, the equation is a recursive equation which is obtained using the self-consistent method. The volume fraction of a material component in the composite material is computed using the equation.

Abstract: A specimen preprocessing system includes a determination section for determining with respect to a height of a specimen container; a specimen container lifting mechanism for lifting an opening portion of the specimen container held in a specimen rack to a same predetermined level based on determination information data of the determination section; and a plug opening mechanism for opening a plug of the specimen container lifted to the same predetermined level by the specimen container lifting mechanism.

Abstract: An upper end 3 of a nozzle tip 2 is adapted to have an inside diameter dimension smaller than an outside diameter of a lower portion of a barrel 4, so that nozzle tips 2 are not piled up. An upper curved surface 11, which is curved in an outer direction of the nozzle tip 2 starting with a boundary portion between the barrel 4 and a leading end opening 5 of the nozzle tip 2 and the leading end opening 5, is formed. A lower curved surface 12 is formed continuously from the upper curved surface 11 to be curved in an inner direction. An angle formed between a line tangent to a boundary portion 13 between the upper curved surface 11 and the lower curved surface 12 and a center axis of the nozzle tip 2 is adapted to fall within a range between 45° and 20°.

Abstract: A ring optical modulator according to an embodiment, includes a ring resonator and an input/output optical waveguide. The ring resonator is configured to have a closed loop optical waveguide in a p-i-n diode structure. A portion of the closed loop optical waveguide and a portion of the input/output optical waveguide positioned close to each other function as an optical coupler. Relationships of Formula (2) to Formula (8) are satisfied by a loss x [%] per revolution of the resonator when the current is turned off and a power coupling ratio y [%] of the optical coupler for the light of the resonant wavelength ?r revolving around the ring resonator from output to input of the optical coupler.