Abstract: The present invention relates to a method of producing a pyrazole-4-carboxamide derivative including subjecting a pyrazole-4-carboxylic acid ester and an amine to an aminolysis reaction in a solvent in the presence of a base, provided that the reaction is completed without removing a by-produced alcohol or phenol outside the system. An industrial production method of a pyrazole-4-carboxamide derivative which is useful as an agricultural fungicide, simply and in high yield and high purity as compared with the conventional method, is provided.

Abstract: The core adjusting process includes a procedure of searching for the position in which the photocurrent of the light-receiving element reaches its peak in each of the X-, Y-, and Z-directions. In the searching procedure, the light emitted from a multimode fiber of a MCP is gathered by a lens and is transmitted to the light-receiving element. A check is then made to determine whether, at in both directions of the search direction, there exist a first and second attenuation positions in which the photocurrent shows a predetermined attenuation relative to a peak value in a search range. If there exist the attenuation positions, a peak position is determined to be a position located within a second predetermined range from the middle point between the attenuation positions, and the relative positions of the receptacle and the CAN package are adjusted to the peak position.

Abstract: An optical semiconductor module has: a semiconductor laser for radiating a laser beam; a lens for converging the laser beam; and an optical connector outputting the laser beam received from the lens to a transmission path. The optical connector has: a fiber ferrule including an optical fiber with an incident plane of the laser beam; and a light attenuator covering the incident plane. Transmittance of the laser beam through the light attenuator is varied according to rotation of the light attenuator on a plane perpendicular to an optical axis. The semiconductor laser, the lens and the optical connector are aligned such that a spot diameter of the laser beam on the incident plane is smaller than a diameter of a core of the optical fiber.

Abstract: There is provided a semiconductor optical receiver module that performs efficient heat dissipation, without incurring an increase in cost. The semiconductor optical receiver module includes a substrate provided on a package, a semiconductor photodetector provided on the substrate, a chip capacitor provided on the substrate, and a preamp IC provided on the package, without the intermediation of the substrate.

Abstract: A receptacle type semiconductor laser module (TOSA) includes a semiconductor laser, a lens, and a fiber stub. The fiber stub has a slantwise cut surface to which a emission light emitted from the semiconductor laser and passing through the lens is incident. The cut surface is arranged in a position deviated from the focus of the lens in the direction of the optical axis of the fiber stub. The semiconductor laser module further includes a fixed optical attenuator arranged on a path of an emission light of the semiconductor laser and having an incident surface being oblique to an optical axis of the semiconductor laser. By such a configuration, a coupling fluctuation caused by an eccentricity of the optical fiber cord connected to the fiber stub and a near-end reflection can be suppressed.

Abstract: A laser module comprises a laser diode secured on a semiconductor substrate for emission of a forward laser beam from its front end and a backward laser beam from a point source on its rear end in a horizontal direction. A photodiode, also secured on the substrate, has a light receiving surface extending in the horizontal direction by length L from an edge proximate to the laser diode for receiving a lower half of the backward laser beam, the light receiving surface being lower than the point source by a vertical distance Y, the edge being spaced a horizontal distance Z from the point source of the laser diode, wherein the horizontal distance Z is equal to or greater than (Y/tan &thgr;)−L, where &thgr; is a vertical angle in which the lower half of the backward laser beam radiates from the point source.