摘要:
An optical communication module includes: a laser light emitting unit that emits laser light; a temperature control unit that controls the temperature of the laser light emitting unit; a power intensity control unit that controls the power intensity of the laser light emitted from the laser light emitting unit; and a setting value storage unit that stores a setting value determined from an optimum power intensity that maintains a predetermined wavelength and satisfies predetermined temperature conditions and predetermined power intensity conditions, and from an optimum temperature that maintains the predetermined wavelength and satisfies the predetermined temperature conditions and the predetermined power intensity conditions. In this optical communication module, the temperature control unit and the power intensity control unit control the temperature and the power intensity of the laser light emitting unit, based on the setting value stored in the setting value storage unit.
摘要:
An optical semiconductor device includes an element in which a laser diode and an optical modulator are integrated, and a circuit that sets a common node of the laser diode and the optical modulator at a reference potential different from a ground potential and drives the laser diode and the optical modulator in opposite directions with respect to the reference potential.
摘要:
A device includes a transistor, and two interdigital capacitors. The transistor is located on an imaginary extension line aligned with a common electrode of the two interdigital capacitors.
摘要:
An optical device includes a rigid pipe provided to cover the outer peripheries of a fixing joint portion and an optical fiber. The tip portion of the rigid pipe has a gap for providing flexibility between the optical fiber and the tip portion. Therefore, the rigid pipe suppresses bending of the optical fiber to avoid concentration of stress in the fixing joint portion for fixing the optical fiber to an optical unit section, thereby avoiding breakage of the optical fiber in the fixing joint portion.
摘要:
A semiconductor device includes a SAW device chip. The SAW device chip is provided on a passive element chip in which a passive element circuit including a transmission line is formed on a semi-insulating compound substrate having one surface set to have a ground potential electrode. In the semiconductor device, even when the width of the transmission line is increased, a high characteristic impedance can be maintained by increasing the thickness of the substrate. This can reduce the resistance of the transmission line and can facilitate matching with the SAW device.
摘要:
A semiconductor amplifier circuit comprises a transimpedance amplifier for amplifying an input signal; a by-pass transistor connected between an input terminal of the transimpedance amplifier and the ground potential; a first resistor, one end of the first resistor being connected to an output terminal of the transimpedance amplifier; a capacitor connected between the other end of the first resistor and the ground potential; a second resistor connected between the other end of the first resistor and the gate of the by-pass transistor via an inverter; and a differential amplifier having a signal input terminal connected to the output terminal of the transimpedance amplifier and a reference-voltage input terminal connected to the other end of the first resistor.
摘要:
In the semiconductor laser module testing device, a temperature control power source changes a temperature of a wavelength locker module, and a wavelength monitoring bias circuit detects an output of a wavelength monitor in the changed temperature range and computes a correlation between a temperature of a semiconductor laser and a wavelength of light output therefrom. Moreover, the wavelength of the output light is locked by controlling the temperature of the wavelength locker module while feeding back the output of the wavelength monitor by a wavelength feedback circuit based on the obtained correlation between the temperature and the wavelength.
摘要:
A semiconductor integrated circuit has a 3-dimmensional interconnection line structure for high-speed operation. One aspect of the present invention, there is provided a monolithic microwave integrated circuit (MMIC) having a 3-dimmensional tournament tree shaped multilayer interconnection lines, wherein a single electric feeding point on a top surface of the MMIC is divided, layer by layer, into plural electrodes on the semiconductor substrate of the MMIC via a plurality of laminated interconnection layers and vertical interconnection layers therebetween shaped like a tournament tree.
摘要:
A protective pattern is formed on a semiconductor substrate in a shape covering a circuit region and exposing an air bridge connecting portion, a metallic film and an insulating film are formed to cover the protective pattern, the metallic film and the insulating film are patterned to form air bridge wiring and an air bridge protective film covering the air bridge wiring, and thereafter, the protective pattern is removed to form a hollow between the air bridge wiring and the circuit region.
摘要:
In a high frequency semiconductor device, a shield plate which is connected to the ground potential is provided above an MMIC structure including line conductors, with an insulating interlayer provided therebetween. By using the shield plate to shield the MMIC, interference caused by external electromagnetic waves or leakage of electromagnetic waves to the exterior can be reduced in a chip alone.