Abstract: A method for manufacturing a monolithically integrated semiconductor optical integrated element comprising a DFB laser, an EA modulator, and a SOA disposed in a light emitting direction, comprising the step of forming a semiconductor wafer on which the elements are two-dimensionally arrayed and aligned the optical axes; cleaving the semiconductor wafer along a plane orthogonal to the light emitting direction to form a semiconductor bar including a plurality of the elements arranged one-dimensionally along a direction orthogonal to the light emitting direction such that the elements adjacent to each other share an identical cleavage end face as a light emission surface; inspecting the semiconductor bar by driving the SOA and the DFB laser through a connection wiring part together; and separating out the semiconductor bar after the inspection to cut the connection wiring part connecting the electrode of the SOA and the DFB laser to isolate from each other.

Abstract: An optical transmitter capable of significantly suppressing a fluctuation in frequency response characteristics due to a fabrication error in internal wire length while reducing a subcarrier size of a module of the optical transmitter is provided. The optical transmitter includes: a subcarrier on which an RF wiring board, a modulated laser chip, and a terminating resistor are mounted and which has a ground pad on an upper surface thereof; and a wire for electrically connecting at least the RF wiring board and the modulated laser chip to each other, wherein the RF wiring board and the modulated laser chip are arranged in a width direction of the subcarrier, and a length of the wire in an electric path which starts at the RF wiring board, passes through the terminating resistor, and reaches the ground pad is 0.5 to 1.5 mm or an inductance of the wire is 0.4 to 1.2 nH.

Abstract: There is provided a high-power directly modulated laser in which oscillation of an SOA unit is suppressed. The high-power directly modulated laser includes a directly modulated laser driven by a drive signal to which a modulation signal is applied and a semiconductor optical amplifier (SOA). The high-power directly modulated laser has an optical absorption element between the directly modulated laser and the SOA. The directly modulated laser, the SOA, and the optical absorption element are monolithically integrated on one substrate.

Abstract: There is provided an optical transmitter having high optical feedback resistance even at the time of high-output operation and capable of suppressing deterioration of optical waveform quality and transmission characteristics. The optical transmitter includes a DBR laser, an EA modulator, a passive optical waveguide, and an SOA that are monolithically integrated on a same substrate, the DBR laser including an active region where current is injected and optical gain is obtained, and two DBR regions that are formed on opposite ends of the active region, the EA modulator optically modulating laser light from the DBR laser, the passive optical waveguide being for guiding modulated light from the EA modulator, the SOA optically amplifying the modulated light from the passive optical waveguide.

Abstract: A semiconductor device includes an electrode which is arranged on an organic material with an insulation film interposed therebetween and which does not easily peel away from the organic material along with the insulation film. An insulation film in a region including pad portions of a phase shift electrode and a modulation electrode has openings at the centers of the pad portions of the phase shift electrode and the modulation electrode, the edge portions of which are formed on the phase shift electrode and the modulation electrode. In this way, the adjoining edges of the phase shift electrode and modulation electrode and the insulation film are all covered by the insulation film so as not to be exposed to the atmosphere.

Abstract: A method for manufacturing a monolithically integrated semiconductor optical integrated element comprising a DFB laser, an EA modulator, and a SOA disposed in a light emitting direction, comprising the step of forming a semiconductor wafer on which the elements are two-dimensionally arrayed and aligned the optical axes; cleaving the semiconductor wafer along a plane orthogonal to the light emitting direction to form a semiconductor bar including a plurality of the elements arranged one-dimensionally along a direction orthogonal to the light emitting direction such that the elements adjacent to each other share an identical cleavage end face as a light emission surface; inspecting the semiconductor bar by driving the SOA and the DFB laser through a connection wiring part together; and separating out the semiconductor bar after the inspection to cut the connection wiring part connecting the electrode of the SOA and the DFB laser to isolate from each other.

Abstract: There is provided a semiconductor optical integrated device having a DFB laser, an EA modulator, and an SOA monolithically integrated, and an output light intensity of the semiconductor optical integrated device is maintained constant. The semiconductor optical integrated device includes: a DFB laser; an EA modulator connected to the DFB laser; an SOA monolithically integrated with the DFB laser and the EA modulator on a same substrate and connected to an output end of the EA modulator; and an optical receiver disposed on an output end side of the SOA and having a same composition as the SOA. The optical receiver is configured to monitor change in a detection value according to an intensity of input light to the optical receiver such that drive currents flowing in the DFB laser and the SOA are feedback controlled.

Abstract: The present invention is to provide an anisotropic porous material for a fluid filter which can perform a separation process of a large amount of fluid with high accuracy, which can achieve high flux, and which can improve detergent properties. The anisotropic porous material includes a plurality of pores. Each of the pores has an anisotropic shape in which a major axis and a minor axis can be defined. An arrangement of the pores has an orientation.

Abstract: A channel switching valve (A) of the present invention includes a discharge hole (14) which discharges water having a proper temperature and a drain hole (15) which drains water having an improper temperature. A part of a first channel (11) extending from a hot water supply port (24b) to the discharge hole and a part of a second channel (11) extending from the hot water supply port to the drain hole are common. Therefore, the channel switching valve can be compact.

Abstract: A friction welded joint structure includes friction welded dissimilar first and second metallic materials. The first metallic material has a rigidity greater than the second metallic material. The angle of the first metallic material to a free edge of the first metallic material, at an end portion of a joined surface between the first and second metallic materials, is greater than or equal to 120 degrees or in the range of from 55 degrees to 85 degrees. A reaction layer between the first and second metallic materials is more than zero and less than or equal to 20 &mgr;m. The first metallic material is copper. The second, which has the smaller rigidity, is aluminum.

Abstract: The present invention relates generally to a joined structure of dissimilar metallic materials having different characteristics. More specifically, the invention relates to a joined structure of a current-carrying contact or arching contact which are used for, e.g., a power breaker, or a coating end structure of a metal base and a coating material for improving conductivity and heat resistance.

Abstract: A friction welded joint structure includes friction welded dissimilar first and second metallic materials. The first metallic material has a rigidity greater than the second metallic material. The angle of the first metallic material to a free edge of the first metallic material, at an end portion of a joined surface between the first and second metallic materials, is greater than or equal to 120 degrees or in the range of from 55 degrees to 85 degrees. A reaction layer between the first and second metallic materials is more than zero and less than or equal to 20 &mgr;m. The first metallic material is copper. The second, which has the smaller rigidity, is aluminum.

Abstract: The present invention relates generally to a joined structure of dissimilar metallic materials having different characteristics. More specifically, the invention relates to a joined structure of a current-carrying contact or arching contact which are used for, e.g., a power breaker, or a coating end structure of a metal base and a coating material for improving conductivity and heat resistance.

Abstract: A voltage non-linear resistor unit is composed of at least one of voltage non-linear resistors which is composed of a columnar sintered body formed by molding and sintering a raw material, the sintered body having both end surfaces having a surface roughness in term of arithmetic average surface roughness Ra of 1 to 2 &mgr;m and being formed with an electrode film layer, a terminal metal fitting formed in a predetermined shape and attached to the voltage non-linear resistor, and a soldering material arranged between the voltage non-linear resistors and between joint surfaces of the voltage non-linear resistor and the terminal metal fitting, the joint surfaces being joined by heating the soldering material and applying a load vertically to the joint surfaces while giving a rotation motion thereto. Such voltage non-linear resistor is effectively assembled into an arrester.