Abstract: The reflective display device includes: a cell having: a display surface; a rear surface; side surfaces; and an interior space; a partition in a shape having radial extension dividing the rear surface into N regions; N rear electrodes respectively provided for the N regions on the rear surface; first side electrodes disposed on a display surface side and second side electrodes disposed on a rear surface side; N display-side electrodes separated by a separator zone in a shape having radial extension; a dielectric layer covering the N rear electrodes; polar liquid portions of N colors respectively disposed in N portions in the interior space; and polarity fluid placed within the interior space. A center of the partition matches with a center of the separator zone. A direction of the radial extension of the partition is different from that of the separator zone.

Abstract: A capsule endoscope includes a capsule enclosure having an external wall surface; an image pickup device provided inside the capsule enclosure; a light source provided inside the capsule enclosure; a plurality of electrode structures each including an electrode, a water repellent layer, and a dielectric layer positioned between the electrode and the water repellent layer, the plurality of electrode structures being provided on the external wall surface of the capsule enclosure such that the electrode is positioned on an external wall surface side of the capsule enclosure; a power supply provided inside the capsule enclosure; at least one reference electrode provided on the external wall surface of the capsule enclosure and connected to reference potential of the power supply; and a drive circuit configured to apply a drive voltage to the plurality of electrode structures based on the power supply.

Abstract: The reflective display device includes: a cell having: a display surface; a rear surface; side surfaces; and an interior space; a partition in a shape having radial extension dividing the rear surface into N regions; N rear electrodes respectively provided for the N regions on the rear surface; first side electrodes disposed on a display surface side and second side electrodes disposed on a rear surface side; N display-side electrodes separated by a separator zone in a shape having radial extension; a dielectric layer covering the N rear electrodes; polar liquid portions of N colors respectively disposed in N portions in the interior space; and polarity fluid placed within the interior space. A center of the partition matches with a center of the separator zone. A direction of the radial extension of the partition is different from that of the separator zone.

Abstract: In a method for fabricating a semiconductor laser device, a plurality of grooves are formed in a surface of one conductive type of an InP layer. The InP layer is thermally treated in an atmosphere including at least a gas containing phosphorus and a gas containing arsenic in a mixed state, thereby forming a plurality of active regions made of InAsP in the plurality of grooves. An other conductive type of semiconductor layer is formed after the active regions are formed.

Abstract: A single wavelength laser module utilizes difference-frequency light and includes a first laser device for oscillating light having a first wavelength and a second laser device arranged parallel to the first laser device for oscillating light having a second wavelength, an optical waveguide device arranged next to the output ends of the first and the second laser device, and an output optical fiber arranged next to the output end of the optical waveguide device. The optical waveguide device includes a coupling waveguide region and an optical wavelength conversion region. The coupling waveguide region combines light having the first wavelength and the second wavelength into a single waveguide by being optically coupled directly to the first and the second laser device. The optical wavelength conversion region includes an optical waveguide for generating difference-frequency light between the first wavelength and the second wavelength.

Abstract: A semiconductor laser device includes an InP substrate and a multi-layered structure formed on the InP substrate, wherein the multi-layered structure includes at least a plurality of active regions for outputting a laser beam, and the plurality of active regions each are provided in each of a plurality of grooves dented toward the InP substrate.

Abstract: A semiconductor laser element including: a three-dimensional photonic crystal structure which has a light confining effect and includes alternating first and second refractive index changing layers, where refractive index of light periodically changes in a first direction in each first refractive index changing layer and periodically changes in a second direction in each second refractive index changing layer; and an active unit which is disposed in a portion having a predetermined refractive index inside the three-dimensional photonic crystal structure, and generates a laser beam in response to reception of electric power.

Abstract: A semiconductor laser element including: a three-dimensional photonic crystal structure which has a light confining effect and includes alternating first and second refractive index changing layers, where refractive index of light periodically changes in a first direction in each first refractive index changing layer and periodically changes in a second direction in each second refractive index changing layer; and an active unit which is disposed in a portion having a predetermined refractive index inside the three-dimensional photonic crystal structure, and generates a laser beam in response to reception of electric power.

Abstract: A semiconductor laser device includes a substrate, a p-type cladding layer and a n-type cladding layer provided on the substrate, and an active layer provided between the p-type cladding layer and the n-type cladding layer, having at least two barrier layers and at least two well layers, the barrier layers and the well layers being disposed alternately. Band offsets in a conduction band between the barrier layers and the well layers are provided so as to increase from the n-type cladding layer aide toward the p-type cladding layer side.

Abstract: A semiconductor laser device includes an InP substrate and a multi-layered structure formed on the InP substrate, wherein the multi-layered structure includes at least a plurality of active regions for outputting a laser beam, and the plurality of active regions each are provided in each of a plurality of grooves dented toward the InP substrate.

Abstract: A single wavelength laser module utilizes difference-frequency light and includes a first laser device for oscillating light having a first wavelength and a second laser device arranged parallel to the first laser device for oscillating light having a second wavelength, an optical waveguide device arranged next to the output ends of the first and the second laser device, and an output optical fiber arranged next to the output end of the optical waveguide device. The optical waveguide device includes a coupling waveguide region and an optical wavelength conversion region. The coupling waveguide region combines light having the first wavelength and the second wavelength into a single waveguide by being optically coupled directly to the first and the second laser device. The optical wavelength conversion region includes an optical waveguide for generating difference-frequency light between the first wavelength and the second wavelength.

Abstract: A semiconductor laser element including: a three-dimensional photonic crystal structure which has a light confining effect and includes alternating first and second refractive index changing layers, where refractive index of light periodically changes in a first direction in each first refractive index changing layer and periodically changes in a second direction in each second refractive index changing layer; and an active unit which is disposed in a portion having a predetermined refractive index inside the three-dimensional photonic crystal structure, and generates a laser beam in response to reception of electric power.

Abstract: An optical module includes a substrate, a waveguide body disposed on the substrate and including an optical waveguide for propagating light, and a photodetector. A curved portion for radiating light propagating through the optical waveguide from the optical waveguide is provided in a part of the optical waveguide, and the photodetector receives light radiated by the curved portion.

Abstract: The semiconductor laser device of the present invention includes a GaAs substrate and a multi-layer structure formed on the GaAs substrate. The multi-layer structure includes an active layer for emitting light. The active layer includes an InNxAsyP1−x−y (where 0<x<1 and 0≦y<1) layer that is lattice-matched with the GaAs substrate.

Abstract: In a distributed feedback semiconductor laser includes an InP substrate and a multiple layer structure formed on a main surface of the InP substrate, the multiple layer structure includes at least an active layer for emitting laser light and a periodical structure for distributed feedback of the laser light, and the periodical structure includes a plurality of semiconductor regions each having a triangular cross section in a direction perpendicular to the main surface of the InP substrate and parallel to a cavity length of the distributed feedback semiconductor laser, the triangular cross section projecting toward the InP substrate.

Abstract: The semiconductor laser of the invention includes: a semiconductor substrate of a first conductivity type; a stripe-shaped multilayer structure, formed on the semiconductor substrate, the stripe-shaped multilayer structure including an active layer; and a current blocking portion formed on the semiconductor substrate on both sides of the stripe-shaped multilayer structure, wherein the current blocking portion has a first current blocking layer of a second conductivity type, and a second current blocking layer of the first conductivity type formed on the first current blocking layer, the first current blocking layer includes a low-concentration region having a relatively low concentration of an impurity of the second conductivity type, and a high-concentration region having an impurity concentration which is higher than that of the low-concentration region, and the low-concentration region is provided at a position closer to the stripe-shaped multilayer structure than the high-concentration region.

Abstract: In a distributed feedback semiconductor laser includes an InP substrate and a multiple layer structure formed on a main surface of the InP substrate, the multiple layer structure includes at least an active layer for emitting laser light and a periodical structure for distributed feedback of the laser light, and the periodical structure includes a plurality of semiconductor regions each having a triangular cross section in a direction perpendicular to the main surface of the InP substrate and parallel to a cavity length of the distributed feedback semiconductor laser, the triangular cross section projecting toward the InP substrate.

Abstract: In a semiconductor laser device 100, an n-type InGaAsP light confinement layer 2, a multiple quantum well active layer 3, a p-type InGaAsP light confinement layer 4, and a p-type InP cladding layer 5 are formed on an n-type InP substrate 1 to be in a mesa structure extending in stripes along the cavity length direction. Moreover, regions on both sides of this striped mesa are buried with a p-type InP current blocking layer 6 and an n-type InP current blocking layer 7. Furthermore, a p-type InP burying layer 8 and a p-type InGaAsP contact layer 9 are formed thereon. The oscillation wavelength of the semiconductor laser device 100 is around 1.3 .mu.m. The stripe width of the active layer 3 is such that the width W1 at the front end face and the width W2 at the rear end face have a relationship of W1<W2, and the stripe width is continuously reduced from W2 to W1 along the cavity length direction.

Abstract: A distributed feedback semiconductor laser which includes a semiconductor substrate of a first conductive type; a semiconductor multi-layer structure provided on the semiconductor substrate and including an active layer for generating laser light; and a gain-coupled diffraction grating provided between the semiconductor substrate and the semiconductor multi-layer structure. The diffraction grating includes a plurality of curved projections periodically arranged at a surface of the semiconductor substrate and a quantum well light absorption layer for covering the plurality of curved projections. The quantum well light absorption layer includes a light absorption area having a first thickness at each border between two adjacent curved projections and a non-light absorption area having a second thickness which is smaller than the first thickness at a top of each of the curved projections.

Abstract: The semiconductor laser of the invention includes: a semiconductor substrate of a first conductivity type; a stripe-shaped multilayer structure, formed on the semiconductor substrate, the stripe-shaped multilayer structure including an active layer; and a current blocking portion formed on the semiconductor substrate on both sides of the stripe-shaped multilayer structure, wherein the current blocking portion has a first current blocking layer of a second conductivity type, and a second current blocking layer of the first conductivity type formed on the first current blocking layer, the first current blocking layer includes a low-concentration region having a relatively low concentration of an impurity of the second conductivity type, and a high-concentration region having an impurity concentration which is higher than that of the low-concentration region, and the low-concentration region is provided at a position closer to the stripe-shaped multilayer structure than the high-concentration region.