Abstract: To provide an optical cross-connect apparatus capable of, even in the case where a light switch becomes large-sized, supervising quality and management information of light signals passing through inside the apparatus with low-cost configuration. For each of the light signals inputted from n pieces of input port, path setting in a branch connection state is performed in order following a control signal from a control section by connecting any one of n pieces of output port with a predetermined supervising port at n×m light SW. Quality and management information are detected from light signals outputted from a supervising output port at a light signal detecting section, and the quality and the management information are supervised at a light signal supervising section.

Abstract: Provided are a high-quality and high-reliability rotary anode target for X-ray tubes, of which the mechanical strength at high temperatures is increased and which is applicable not only to low-speed rotation (at least 3,000 rpm) but also even to high-speed rotation at high temperatures, and also a method for producing it. The rotary anode has a two-layered structure to be formed by laminating an Mo alloy substrate that comprises from 0.2% by weight to 1.5% by weight of TiC with the balance of substantially Mo, and an X-ray generating layer of a W—Re alloy that overlies the substrate.

Abstract: Provided are a high-quality and high-reliability rotary anode target for X-ray tubes, of which the mechanical strength at high temperatures is increased and which is applicable not only to low-speed rotation (at least 3,000 rpm) but also even to high-speed rotation at high temperatures, and also a method for producing it. The rotary anode has a two-layered structure to be formed by laminating an Mo alloy substrate that comprises from 0.2% by weight to 1.5% by weight of TiC with the balance of substantially Mo, and an X-ray generating layer of a W—Re alloy that overlies the substrate.

Abstract: A device comprises a plurality of nodes and four optical transmission lines of clockwise and counter-clockwise working operation lines and clockwise and counter-clockwise stand-by lines which connect the nodes in form of a ring. Each node is provided with first and second terminal sections including a receiver and transmitter, with a first optical path switch for switching the optical path between four output terminals of the counter-clockwise working operation and stand-by optical transmission lines, the second terminal section, and output terminal of a first stand-by line, and four input terminals of the clockwise operation and stand-by optical transmission lines, first terminal sections, and a second stand-by line.

Abstract: A ring network is composed of an even-number of optical fibers wherein each pair of optical fibers forms a bidirectional transmission line and a plurality of nodes coupled through the optical fibers in ring topology. In this ring system, each of the nodes includes the even-number of Add/Drop circuits coupled to the optical fibers, respectively, and the even-number of optical transceivers each including an optical transmitter and an optical receiver. A switch changes a combination of an Add/Drop circuit and each of the optical transmitter and the optical receiver.

Abstract: The n.times.n light matrix switch of the present invention comprises a n:1 optical coupler for wavelength-multiplexing the n input light signals having different wavelengths, a 1:n optical divider for dividing the wavelength-multiplexed light signals to n light signals, n wavelength tunable light band pass filter for extracting only an arbitrary one wavelength component out of n-divided light signals, and a controlling circuit for controlling the pass center frequency of the n wavelength tunable light band pass filter. The n wavelength tunable light band pass filters connected to the n output terminals supply all the n input light signal components which are wavelength-division-multiplexed. Thereby, any output terminal can select an arbitrary light signal out of n inputs quite independently from other output terminals. Further, there are n objects to be controlled which prescribes the connecting condition between input signal and output signal, this number is less than that of the conventional n.times.

Abstract: In optical wavelength-division multiplex transmission equipment where a plurality of nodes are connected in the form of a ring, the nodes are connected by four optical fiber transmission lines consisting of a pair of working transmission lines and a pair of protection transmission lines which are capable of bidirectional optical transmission. Four different optical information signals are sent onto four transmission lines by the transmission wavelengths assigned individually to a plurality of nodes, and a desired single wavelength is separated and extracted from the optical signals that are received from the transmission line. The optical signals consisting of the other wavelength components are multiplexed with the aforementioned transmission wavelength and are sent onto the ring-shaped transmission line again. Since a single wavelength component is assigned to each node, there is no need to set protection wavelengths, and all wavelengths can be used as service wavelengths.

Abstract: The optical filter of the invention has a optical filter section for transmitting only the light having wavelength included in the transmission wavelength band prescribed by the wavelength control signal out of the input signal light and for supplying the transmission wavelength band signal light, a low frequency signal generator, an optical coupler, a photoelectric converter, a specific frequency signal component extractor, a wavelength controller, and a signal superposer. The low frequency signal generator generates a changing signal having a previously prescribed frequency. The optical coupler branches partially the transmission wavelength band signal light through the optical filter and outputs the branched signal light from one terminal. The photoelectric converter converts the branched signal light to an electric signal. The specific frequency signal component extractor extracts the signal component of the changing signal frequency, and outputs a specific frequency signal.

Abstract: A monitor control signal receiving apparatus for an optical fiber amplifier includes a laser diode, an optical coupler, a rare-earth-element-doped optical fiber, a pin photodiode, a controller, and a monitor signal extractor. The laser diode generates pump light. The optical coupler optically wavelength-multiplexes an input optical signal and the pump light from the laser diode. The rare-earth-element-doped optical fiber receives the optical signal and pump light from the optical coupler. The pin photodiode converts part of an optically amplified optical signal from the rare-earth-element-doped optical fiber into an electrical signal. The controller compares the electrical signal from the photoelectric converter with a reference voltage to control the laser diode such that an output level of the optical signal from the optical fiber is kept constant. The monitor signal extractor extracts a monitor control signal from an output from the controller.

Abstract: A process for producing L-lysine by fermentation, comprising the steps of aerobically cultivating a strain having the ability to produce L-lysine and derived from Nocardia alkanoglutinousa No. 223, in a culture medium containing an assimilable carbon source and an assimilable nitrogen source, to accumulate L-lysine in the culture medium and then recovering L-lysine.