Abstract: It is to prevent optical coupling of the light that makes incident on an optical film obliquely and a light-receiving part of a light-receiving element, in an optical system where the light-receiving element is disposed on an emission-face side of the optical film that is formed with a dielectric multilayer film. A light-shielding film layer is formed on the light-receiving element itself. That is, the light-shielding film layer is formed on the incident-face side of the light-receiving element, and an opening is formed on the light-shielding film layer at a position that corresponds to a p-region. The size of the opening is so set that only the parallel light or the light close to that state is optically coupled with the p-region, based on a distance from the incident face to the p-region of the light-receiving part region.

Abstract: A semiconductor laser diode, in which an active layer is formed close to a bottom surface thereof, is fixed to a top surface of a substrate by means of solder layers in such a condition that the bottom surface of the semiconductor laser diode faces the top surface of the substrate, which is covered with a SiO2 layer. The active layer is interposed between a pair of V grooves. The right and left solder layers partially fill a clearance formed between the bottom surface of the semiconductor laser diode and the top surface of the substrate, leaving a vacant space in the vicinity of the active layer and the V grooves. Accordingly, the distortion of and the residual stress exerted on the active layer can be decreed noticeably, so that the operation of an optical semiconductor module can be stabilized.

Abstract: A V-shaped profile is on both sides of a silicon substrate. A light emitting element is mounted on one side and a light receiving element is mounted on the opposite side. An optical connector is constituted by molding integrally an optical fiber for transmission coupled to the light emitting element with an optical fiber for light reception coupled to the light receiving element. The respective extreme end surfaces of the optical fibers on the molded sides of the optical fibers for transmission as well as for light reception are served for light transmitting and receiving ends. When a thickness of the substrate is equal to a distance between both the optical fibers for transmission and reception as well as to a thickness between both the optical fibers contained in an optical connector, no polymer light waveguide for adjusting a distance between fibers is required.

Abstract: A semiconductor laser diode, in which an active layer is formed close to a bottom surface thereof, is fixed to a top surface of a substrate by means of solder layers in such a condition that the bottom surface of the semiconductor laser diode faces the top surface of the substrate, which is covered with a SiO2 layer. The active layer is interposed between a pair of V grooves. The right and left solder layers partially fill a clearance formed between the bottom surface of the semiconductor laser diode and the top surface of the substrate, leaving a vacant space in the vicinity of the active layer and the V grooves. Accordingly, the distortion of and the residual stress exerted on the active layer can be decreed noticeably, so that the operation of an optical semiconductor module can be stabilized.

Abstract: An optical system unit for optical transceiver is fabricated integral with lenses by molding of a resin material for providing a desired level of the optical characteristics with no use of mirrors. The optical system unit for optical transceiver 201 for optically coupling with a connector 202 having a fiber optic cable 205 has a pair of convex lenses 212 and 213 thereof provided to face the coupling end of a transmission optical fiber 203 and the coupling end of a reception optical fiber 204 respectively. The two lenses 212 and 213 may be identical in the optical characteristics. A lead frame 215 having two steps is provided beneath the two lenses 212 and 213. A light emitting device 216 and a light receiving device 217 are mounted on the two, upper and lower, steps of the lead frame 215 respectively. The lead frame 215 is carefully bent at a certain angle, aligned with the axes of the optical fibers, and embedded in the resin material.

Abstract: A light receiving device including an optical waveguide medium (optical fiber) for emitting signal light from an outgoing end, and a light receiving element for receiving the signal light by a light receiving surface and converting the signal light into an electric signal. The outgoing end has a surface cut with a blade saw perpendicular to a traveling direction of the signal light, and an index-matching material exhibiting a refractive index larger than 1 but less than a refractive index of the light receiving element, fills between the outgoing end and the light receiving surface. The surface roughness Rz of the end surface of the optical fiber is preferably over 0.04 &mgr;m. The formation under this condition may involve the use of the blade saw having an abrasive grain specified by a grain number smaller than #2000. The light receiving element is disposed so that the light receiving surface is oblique to the traveling direction of the signal light.

Abstract: An optical system unit for optical transceiver is fabricated integral with lenses by molding of a resin material for providing a desired level of the optical characteristics with no use of mirrors. The optical system unit for optical transceiver 201 for optically coupling with a connector 202 having a fiber optic cable 205 has a pair of convex lenses 212 and 213 thereof provided to face the coupling end of a transmission optical fiber 203 and the coupling end of a reception optical fiber 204 respectively. The two lenses 212 and 213 may be identical in the optical characteristics. A lead frame 215 having two steps is provided beneath the two lenses 212 and 213. A light emitting device 216 and a light receiving device 217 are mounted on the two, upper and lower, steps of the lead frame 215 respectively. The lead frame 215 is carefully bent at a certain angle, aligned with the axes of the optical fibers, and embedded in the resin material.

Abstract: A photosemiconductor device mounted structure includes a plurality of tapered projections, a photosemiconductor device, second Au electrodes, and AuSn solder. The tapered projections are formed on a surface of an Si substrate. The photosemiconductor device has first Au electrodes. The second Au electrodes are formed on the tapered projections to correspond to the first Au electrodes. The AuSn solder bonds the first and second Au electrodes to each other.

Abstract: A DC motor pulse signal generating device comprising a DC motor including a rotor frame with a magnet for pulse generation and a substrate for supporting the rotor frame. A magnetic sensor is mounted on the substrate for detecting magnetic flux generated from the magnet and outputting a signal. A positioning groove is formed on the substrate to receive the magnetic sensor on a fixed position. Thereby, the gap between the magnetic sensor and the magnet is fixed so that stable pulses are generated, and the height of the center of the magnetic sensor is lowered to the level of the center of the magnet so that magnetic flux is detected most efficiently by the magnetic sensor.

Abstract: A frequency generator includes a frequency generating magnet, a plurality of generating coils arranged at the polar periphery of the frequency generating magnet, the coils each comprising linear elements located at a distance from the frequency generating magnet such that the linear elements of the coils detect the same magnetic signals at the same time, the coils being crossed with each other, and a plurality of canceling coils provided on one side of the direction in which the generating coils are arranged with respect to the frequency generating magnet, the canceling coils and the generating coils being alternately connected in series.