Abstract: A control system configured to reduce the number of terminals of a connector in an electronic control unit and reduce the insertion/extraction force of the connector includes an ECU having a first connector unit, and a wire harness unit having a second connector unit to be connected to the first connector unit. The ECU includes a multiplexing control circuit and a first signal line serving as a transmission path for a multiplexed signal. The second connector unit is provided with a second signal line serving as a transmission path for the multiplexed signal transmitted via the first signal line, and a multiplexing control circuit. The multiplexing control circuit performs at least one of a process of separating signals from the multiplexed signal transmitted via the second signal line and a process of multiplexing a plurality of signals and transmitting a multiplexed signal to the second signal line.

Abstract: A control system configured to reduce the number of terminals of a connector in an electronic control unit and reduce the insertion/extraction force of the connector includes an ECU having a first connector unit, and a wire harness unit having a second connector unit to be connected to the first connector unit. The ECU includes a multiplexing control circuit and a first signal line serving as a transmission path for a multiplexed signal. The second connector unit is provided with a second signal line serving as a transmission path for the multiplexed signal transmitted via the first signal line, and a multiplexing control circuit. The multiplexing control circuit performs at least one of a process of separating signals from the multiplexed signal transmitted via the second signal line and a process of multiplexing a plurality of signals and transmitting a multiplexed signal to the second signal line.

Abstract: An optical assembly is disclosed where the optical assembly provides an optical device and a holder including a sleeve, a skirt, and a lens. The sleeve has a bore, into which an external optical fiber is set to couple with the optical device, providing a target surface in an end thereof. The target surface includes an aiming index to indicate the axis of the lens.

Abstract: A method of manufacturing an optical module includes the steps of applying the invisible light onto the resin member and the optical device, observing, with use of a camera, a part of the resin member located at the optical fiber coupling plane and an image formed at the optical fiber coupling plane by the optical device active layer while applying the invisible light onto the resin member and the optical device, aligning positions of the resin member and the circuit board with respect to each other while observing the part of the resin member located at the optical fiber coupling plane and the image formed at the optical fiber coupling plane, and fixing the resin member to the circuit board while maintaining the aligned positions of the resin member and the circuit board.

Abstract: A method of manufacturing an optical module includes the steps of applying the invisible light onto the resin member and the optical device, observing, with use of a camera, a part of the resin member located at the optical fiber coupling plane and an image formed at the optical fiber coupling plane by the optical device active layer while applying the invisible light onto the resin member and the optical device, aligning positions of the resin member and the circuit board with respect to each other while observing the part of the resin member located at the optical fiber coupling plane and the image formed at the optical fiber coupling plane, and fixing the resin member to the circuit board while maintaining the aligned positions of the resin member and the circuit board.

Abstract: An optical data link includes a circuit board and an optical module component. The circuit board includes first and second mounting sections on a principal plane thereof. A step is formed between the first mounting section and the second mounting section. The first mounting section has the optical module component, and the second mounting section has an electron device. The optical module component includes a mounting component, a semiconductor optical device, and an optical transmission medium. The semiconductor optical device of the optical module component is electrically connected to the electron device, and is mounted on a first region of the mounting component. The optical transmission medium is supported by a second region of the mounting component, and is optically coupled with the semiconductor optical device.

Abstract: An optical receiver includes a light-receiving part and a control part. The light-receiving part includes an APD, a PIN-PD, and a branching optical device. First signal light is incident on the light-receiving part and is divided into second signal light and third signal light which are incident on the APD and the PIN-PD, respectively, by the branching optical device. Due to this structure, the third signal light is incident on the PIN-PD without the quantity thereof being varied depending on the polarization state of the first signal light. The control part generates a supply voltage at which a desired avalanche multiplication factor is obtained in the APD on the basis of the output current from the PIN-PD. According to the above-described structure, the avalanche multiplication factor of the APD is accurately controlled on the basis of the output current of the PIN-PD.

Abstract: An optical receiver is provided with an optical-signal-receiving section and a controlling section. The optical-signal-receiving section incorporates a photodetector. The photodetector has an APD. Through a passivation film, a photoconductor is placed on a portion of a surface of the APD which remains unoccupied by an optical-signal-receiving area of the APD. When this structure is employed, the signal for controlling the avalanche multiplication factor of the APD can be obtained from the photoconductor. Consequently, the signal can be obtained with a simple structure. Furthermore, the photoconductor has a good linearity of the output current even to a weak lightwave. As a result, the output current I for controlling the avalanche multiplication factor of the APD can be obtained with high accuracy.

Abstract: The present invention provides an optical receiver that uses an avalanche photodiode (APD) whose multiplication factor m is controlled to compensate the temperature dependence thereof. An optical module of the present invention includes a light-receiving device in addition to the APD. The light-receiving device may be a semiconductor thin film or a PIN photodiode, and is disposed in front of the APD. Accordingly, the light-receiving device receives a portion of signal light, and transmits a rest portion thereof. The APD receives the rest portion of the signal light. The bias voltage applied to the APD is so controlled that a first photocurrent generated in the light-receiving device and a second photocurrent generated in the APD maintain a constant ratio.

Abstract: An optical receiver includes a PIN photodiode (PIN-PD) having an incident surface for receiving signal light, the PIN-PD transmitting a part of the signal light to the surface opposite to the incident surface, and an avalanche photodiode (APD) having an incident surface for receiving light transmitted through the PIN-PD. In the optical receiver, the ratio of the quantity of signal light detected by the PIN-PD and the ratio of the quantity of signal light detected by the APD are not affected by the polarization state of the signal light incident on the optical receiver, and accordingly the avalanche multiplication factor of the APD is suitably controlled on the basis of the signal light detected by the PIN-PD.

Abstract: An optical module includes a semiconductor optical device, an optical fiber, a ferrule, and a mounting component. The optical fiber is optically coupled to the semiconductor optical device. The ferrule holds the optical fiber. The mounting component includes a first support groove for supporting the ferrule and a second support groove for supporting the optical fiber. The semiconductor optical device is mounted on the mounting component. The first and second support grooves are sequentially arranged in a direction of a predetermined axis. The second support groove has one end and the other end. The depth of the second support groove decreases from the one end toward the other end. With such a structure, the optical module allows the optical fiber to be positioned with high accuracy onto the mounting component.

Abstract: An optical module 11a comprises an optical-receptacle housing 13, an optical-communication subassembly 15, and a holder 17. The flange portion 13b has a plurality of first portions 13c, which extend along a reference plane perpendicular to a predetermined axis, Ax, and a plurality of second portions 13d, each of which is positioned between the first portions 13c. The outer periphery of the first portions 13c is positioned at the outside of a reference cylinder whose center is coincident with the predetermined axis Ax. The outer periphery of the second portions 13d is positioned at the inside of the reference cylinder. The optical-receptacle housing 13 and the holder 17 are temporarily fixed to each other at the second portions 13d of the flange portion 13b through second bonding members 27a to 27d. The optical-receptacle housing 13 and the holder 17 are further fixed with increased strength to each other at the first portions 13c of the flange portion 13b through first bonding members 25a to 25d.

Abstract: An optical transmission and receiver module suitable for a single-fiber bi-directional communication includes a light emitting device, a photodiode, an optical path routing element which allows light emitted from the light emitting device and light directed to the photodiode to pass through the element and which changes their optical paths, as required, and a lens transparent to both light emitted from light emitting device and light directed to the photodiode.

Abstract: An optical module 11a comprises an optical-receptacle housing 13, an optical-communication subassembly 15, and a holder 17. The flange portion 13b has a plurality of first portions 13c, which extend along a reference plane perpendicular to a predetermined axis, Ax, and a plurality of second portions 13d, each of which is positioned between the first portions 13c. The outer periphery of the first portions 13c is positioned at the outside of a reference cylinder whose center is coincident with the predetermined axis Ax. The outer periphery of the second portions 13d is positioned at the inside of the reference cylinder. The optical-receptacle housing 13 and the holder 17 are temporarily fixed to each other at the second portions 13d of the flange portion 13b through second bonding members 27a to 27d. The optical-receptacle housing 13 and the holder 17 are further fixed with increased strength to each other at the first portions 13c of the flange portion 13b through first bonding members 25a to 25d.

Abstract: An optical receiver includes an avalanche photodiode (APD) having a light-receiving area provided on a face of a first substrate, the light-receiving area receiving a part of signal light; a photodetector having a light-receiving area provided on a face of a second substrate, the light-receiving area receiving the other part of the signal light; and a mounting member having a principal plane on which the APD and the photodetector are mounted. Due to this structure, crosstalk between the APD and the photodetector does not occur and an avalanche multiplication factor of the APD can be controlled on the basis of the output current of the photodetector.

Abstract: An optical receiver comprises a PD for receiving an incident light from an optical fiber, a preamplifier IC for amplifying an electrical signal from the PD, a submount on which the PD and the preamplifier IC are mounted on the same plane, and a package on which the submount is mounted. The PD and the preamplifier IC are directly connected to each other by a wire, and these components are both mounted on the same submount. Therefore, the distance between the PD and the preamplifier IC can be reduced, and parasitic inductance, parasitic capacitance, etc. can be greatly reduced. As a result, an optical receiver is provided which has reduced parasitic inductance and parasitic capacitance, and which is optimum for high speed response.

Abstract: An optical receiver comprises (a) an optical fiber, (b) a rear-illuminated type PD for receiving incoming light emerging from the optical fiber, (c) a submount supporting the PD, (d) a coaxial type package housing the submount, and (e) a preamplifier IC for amplifying electric signals from the PD. In particular, the submount is provided with a reflecting face for reflecting the incoming light so that the light can enter the PD. The submount may be provided with an optical path-forming groove having at least one reflecting face for introducing and reflecting the incoming light so that the light can enter the light-receiving portion of the PD mounted on the submount. This structure enables the production of an optical receiver most suitable for high-speed response and excellent in productivity. A method of producing the optical receiver is also offered.

Abstract: An optical data link includes a circuit board and an optical module component. The circuit board includes first and second mounting sections on a principal plane thereof. A step is formed between the first mounting section and the second mounting section. The first mounting section has the optical module component, and the second mounting section has an electron device. The optical module component includes a mounting component, a semiconductor optical device, and an optical transmission medium. The semiconductor optical device of the optical module component is electrically connected to the electron device, and is mounted on a first region of the mounting component. The optical transmission medium is supported by a second region of the mounting component, and is optically coupled with the semiconductor optical device.

Abstract: It is an object of the present invention to provide a driving circuit which can drive a light emitting element in spite of a reduced power supply voltage and which is thus suitable for size reduction. The present invention provides a driving circuit which supplies a bias current to a light emitting element and which carries out modulation on the basis of voltage driving, the driving circuit comprising a boosting circuit that increases a power supply voltage Vcc, a resistance element connected between an output of the boosting circuit and an anode terminal of the light emitting element, and a capacitive element connected to the anode terminal of the light emitting element to supply a modulation signal to the light emitting element for voltage driving.

Abstract: An optical receiver is provided with an optical-signal-receiving section and a controlling section. The optical-signal-receiving section incorporates a photodetector. The photodetector has an APD. Through a passivation film, a photoconductor is placed on a portion of a surface of the APD which remains unoccupied by an optical-signal-receiving area of the APD. When this structure is employed, the signal for controlling the avalanche multiplication factor of the APD can be obtained from the photoconductor. Consequently, the signal can be obtained with a simple structure. Furthermore, the photoconductor has a good linearity of the output current even to a weak lightwave. As a result, the output current I for controlling the avalanche multiplication factor of the APD can be obtained with high accuracy.