Abstract: There is provided an apparatus capable of reducing a waveform distortion of an outgoing light when the light of an optical wavelength in a certain specific narrow range is incident upon an optical fiber.

Abstract: The object of the present invention is to provide an apparatus capable of measuring wavelength dispersion characteristic and other characteristics by using only a single fiber pair.

Abstract: A push-button switch comprising cases, a slide member disposed movably in the cases, a heart-shaped cam groove formed in the slide member, and a locking pin for locking the slide member in a depressed position in cooperation with the heart-shaped cam groove, wherein the slide member is provided with a movable member movable in a direction orthogonal to the moving direction of the slide member, part of the heart-shaped cam groove is formed on one end side of the movable member, a drive portion is formed on an opposite end side of the movable member, and by operating the drive portion the movable member is moved to release the locking pin from the locking position.

Abstract: A push switch including a rotatably supported movable contact member with a movable contact portion which comes into contact with and separates from a stationary contact; and a cam shaft rotatably disposed between the lower surface of a plunger and the movable contact member. The switching driver portion of the cam shaft slides on the movable contact member. The force used to push down the plunger is exerted on the movable contact member through the switching driver portion to tilt the movable contact member.

Abstract: A polarization state changing apparatus which can change the polarization state of an incident polarized light entering to an optical fiber to any direction and can output is provided. This polarization state changing apparatus, in an embodiment, comprises three polarization plane maintaining optical fibers 10, 20 and 300 which are serially connected at two polarization plane changing parts 30 and 30'. Those three polarization plane maintaining optical fibers are connected at the polarization plane changing parts 30 and 30'so that the optical axes X and Y of the adjacent optical fibers are mutually rotated at an angle of 45 degrees in terms of the fiber axis. Stress application parts for applying stress to each of the polarization plane maintaining optical fibers are provided.

Abstract: An optical FM characteristics measurement apparatus for measuring the light signal from a laser diode is capable of automatically and precisely determining a frequency discriminating point of the interferometer and maintain the discriminating point during the measurement. The measurement apparatus can distinguish an intensity modulation component from a frequency modulation component in the light signal from the laser diode, therefore, it can improve measurement accuracy and operation efficiency.

Abstract: A system for automatically correcting the position of the slide of a press comprises a position adjusting assembly for adjusting the up-down relative position relationship between the slide and a bolster while the press is in operation, a distance detecting unit for directly or indirectly detecting the relative distance between the bolster and the slide at the bottom dead center, and a control unit for controlling the position adjusting assembly based on the output of the distance detecting unit so that the relative distance between the bolster and the slide at the bottom dead center will be within a predetermined range during the operation of the press.