Abstract: A wavelength division multiplexing optical monitor has optical fiber connectors disposed at opposite ends thereof, an optical fiber that extends between the optical fiber connectors at the opposite ends and on which a fiber grating is formed that disperses part of the light transmitted in the optical fiber, a ferrule that covers the optical fiber and is optically transparent at least in a part facing the fiber grating, a photodiode array that has an array of multiple photodiodes that receive light of wavelengths dispersed by the fiber grating and transmitted through the ferrule, and a light-emitting diode array that has an array of multiple light-emitting diodes that emit light depending on the intensities of light received at the respective photodiodes.

Abstract: In an optical spectrum analyzer comprising a spectrograph and a photodevice array, and an optical spectrum detecting method, a wavelength deviation, from an assigned wavelength, of a light detected by a photodevice array which detects a wavelength of a diffraction light or a non-diffraction light from an acoustooptic device, is detected and a feedback control to a diffraction angle of the acoustooptic device is performed. Also, without using a feedback control, an exit light and a diffraction light from the acoustooptic device are respectively received by two photodevice arrays and the photodevices are arranged in order to mutually compensate gaps between the photodevices, whereby a center of each photodevice is similarly made coincide with a peak of an optical beam to be received.

Abstract: In an optical spectrum analyzer comprising a spectrograph and a photodevice array, and an optical spectrum detecting method, a wavelength deviation, from an assigned wavelength, of a light detected by a photodevice array which detects a wavelength of a diffraction light or a non-diffraction light from an acoustooptic device, is detected and a feedback control to a diffraction angle of the acoustooptic device is performed. Also, without using a feedback control, an exit light and a diffraction light from the acoustooptic device are respectively received by two photodevice arrays and the photodevices are arranged in order to mutually compensate gaps between the photodevices, whereby a center of each photodevice is similarly made coincide with a peak of an optical beam to be received.

Abstract: In an optical spectrum analyzer comprising a spectrograph and a photodevice array, and an optical spectrum detecting method, a wavelength deviation, from an assigned wavelength, of a light detected by a photodevice array which detects a wavelength of a diffraction light or a non-diffraction light from an acoustooptic device, is detected and a feedback control to a diffraction angle of the acoustooptic device is performed. Also, without using a feedback control, an exit light and a diffraction light from the acoustooptic device are respectively received by two photodevice arrays and the photodevices are arranged in order to mutually compensate gaps between the photodevices, whereby a center of each photodevice is similarly made coincide with a peak of an optical beam to be received.

Abstract: In an optical spectrum analyzer comprising a spectrograph and a photodevice array, and an optical spectrum detecting method, a wavelength deviation, from an assigned wavelength, of a light detected by a photodevice array which detects a wavelength of a diffraction light or a non-diffraction light from an acoustooptic device, is detected and a feedback control to a diffraction angle of the acoustooptic device is performed. Also, without using a feedback control, an exit light and a diffraction light from the acoustooptic device are respectively received by two photodevice arrays and the photodevices are arranged in order to mutually compensate gaps between the photodevices, whereby a center of each photodevice is similarly made coincide with a peak of an optical beam to be received.

Abstract: An optical parallel receiving module receives optical signals transmitted in parallel in a plurality of channels by using optical fibers. The optical parallel receiving module includes photo-electric conversion elements for converting received signals which are electric signals as received signals, limiter amplifiers for comparing the received signals and a threshold level, and data decision circuits for recognizing data at a timing in every period of received data using a reference clock.

Abstract: A multicore optical connector comprising: a first connector part comprising a fiber array, a refractive index matching plate for preventing the diffusion of beams, and a lens array, in order mentioned thereabove, and a second connector part comprising a fiber array and a lens array, and wherein the diameter of each of the parallel beams that may be emitted outwardly from the lens array of the second connector part is relatively larger than that of the parallel beams that may be emmited outwardly from the lens array of the first connector part, and the first connector part and the second connector part are optically coupled such that both lens array are opposed to each other.

Abstract: A fiber-optic gyro includes a laser diode, a light detector, first and second lenses arranged on both sides of a half mirror, and a coil-like optical fiber which is arranged so that the two ends of the optical fiber confront the first and second lenses, respectively. Light from the laser diode is incident on the half mirror through the first lens, the light reflected from the half mirror is incident from one end of the coil-like optical fiber through the first lens, and the light transmitted through the half mirror is incident from the other end of the coil-like optical fiber through the second lens. Therefore the light is propagated through the coil-like optical fiber in opposite directions, light from the coil-like optical fiber is synthesized and is incident on the light detector, and the speed of the rotation angle is detected by the output of the light detector.