Abstract: When set values of a wavelength and a output level are input, the input set values (of the wavelength and the output level) are collated with data (A), and then, an approximate temperature of a DFB laser is calculated. The calculated approximate temperature is collated with data (B), and then, a output regulation value of the DFB laser is calculated. The input set value (the output level) is added to the power regulation value, and then, an optical output controlling value is calculated. The optical output level of the DFB laser is controlled. The optical output controlling value and the input set value (of the wavelength) are collated with the data (A), and then, a temperature controlling value of the DFB laser is calculated. Consequently, the temperature of the DFB laser is controlled.

Abstract: A light source 1 is connected to a first terminal of an optical branch coupler 2, and a first optical sensor 3 is connected to a second terminal. A second optical sensor 4 is connected to a fourth terminal, and a master optical connector 7 is connected to a third terminal. While a measured optical fiber 5 is connected to the master optical connector 7, the power of light received by the first optical sensor 3 and the power of light received by the second optical sensor 4 are detected. The insertion loss and return loss of the optical fiber 5 are computed from the power values of received light detected by a measurement unit 10.

Abstract: An apparatus for inspecting a multi-core optical fiber having a plurality of cores arranged in one plane includes a light source 10 having a plurality of optical output terminals which are connected to the incident ends of the respective cores of the multi-core optical fiber and used for putting optical signals into the respective cores thereof; optical signal taking means (12 and 14) for taking out the optical signal emitted from the emission end of each core of the multi-core optical fiber in a time series mode according to the alignment order of emission-side cores of the multi-core optical fiber; optical signal detecting means (16 and 18) for detecting the optical signal thus taken out by the optical signal taking means; and signal processing means 20 for verifying core numbers of the respective cores of the multi-core optical fiber on the basis of the signal patterns of detection outputs of the optical signal detecting means.

Abstract: When set values of a wavelength and a output level are input, the input set values (of the wavelength and the output level) are collated with data (A), and then, an approximate temperature of a DFB laser is calculated. The calculated approximate temperature is collated with data (B), and then, a output regulation value of the DFB laser is calculated. The input set value (the output level) is added to the power regulation value, and then, an optical output controlling value is calculated. The optical output level of the DFB laser is controlled. The optical output controlling value and the input set value (of the wavelength) are collated with the data (A), and then, a temperature controlling value of the DFB laser is calculated. Consequently, the temperature of the DFB laser is controlled.

Abstract: A light source 1 is connected to a first terminal of an optical branch coupler 2, and a first optical sensor 3 is connected to a second terminal. A second optical sensor 4 is connected to a fourth terminal, and a master optical connector 7 is connected to a third terminal. While a measured optical fiber 5 is connected to the master optical connector 7, the power of light received by the first optical sensor 3 and the power of light received by the second optical sensor 4 are detected. The insertion loss and return loss of the optical fiber 5 are computed from the power values of received light detected by a measurement unit 10.

Abstract: An apparatus for verifying the wire gauges of a multi-core optical fiber including a multi-output light source unit having a plurality of output terminals, and an integrated light receiving device having a plurality of light receiving elements which are integrated into one body. In the apparatus, outputs of the multi-output light source unit are inputted into the respective cores of the multi-core optical fiber, rays of output light from the multi-core optical fiber are collectively received by the integrated light receiving device, and a plurality of outputs of the integrated light receiving device are inputted into an operational processor circuit, so that the wire gauges are verified from the light receiving position of the integrated light receiving device.

Abstract: The object of the present invention is to provide an optical pulse generator which very stably generates for a long period of time a high cycling frequency optical pulse chain. In order to obtain this object, in a ring type resonator R, the present invention provides an optical path length regulator 14 which performs high precision optical path length adjustment and an optical path length regulator 60 which performs wide range optical path length adjustment, and extracts a clock signal by converting an optical pulse emitted from the ring type resonator R to an electrical signal by a clock extractor 42, detects the frequency difference between a base frequency signal output form a synthesizer 52 by a frequency difference detector 50, and controls said optical path length regulator 14 and said optical path length regulator 60.

Abstract: According to the present invention, damage to a photo-detector disposed in clock signal extractor by means of an optical pulse having an optical power exceeding a rated value is prevented. A ring resonator generates a repetitive, high-frequency optical pulse. Optical branching circuit branches a portion of the optical pulse circulating through ring resonator, while optical branching circuit further branches a portion thereof to protective device. Pumping source generates an excitation light for exciting a rare-earth doped optical fiber. Optical multiplexer couples the optical pulse branched by optical branching circuit, and the excitation light. Upon excitation by means of the excitation light, rare-earth doped optical fiber amplifies and emits the incoming optical pulse. The optical power of the excitation light is adjusted such that the output of rare-earth doped optical fiber reaches a saturation power.