Abstract: A decrease in output power due to a foreign matter present on a base at the time of forming a thin film solid electrolyte layer is limited, and an increase in yield even when an area of a fuel battery cell is increased, is obtained. The fuel battery cell has a membrane electrode assembly including a lower electrode layer, first and second solid electrolyte layers, and an upper electrode layer formed on a support substrate. An interface between the first and second solid electrolyte layers is flat as compared with an interface between the lower electrode layer and the solid electrolyte layer, and the second solid electrolyte layer has a thickness at which a leakage current between the first solid electrolyte layer and the second solid electrolyte layer is less than an allowable value even when an output voltage of the fuel battery cell is generated.

Abstract: A formed body of Cu—Al—Mn-based shape-memory alloy may include a screw portion, wherein the screw portion is a form-rolled portion. A method for producing a formed body of Cu—Al—Mn-based shape-memory alloy may involve forming a screw portion having superelasticity by plastically working at least a portion of a material for the formed body with form-rolling in a state that a crystal structure is an A2-type structure and then, subjecting heat-treatment so as to convert the A2-type crystal structure into an L21-type crystal structure. The screw portion can be formed with good working property, and has excellent fatigue resistance and breaking resistance.

Abstract: Provided is a display device with extremely high resolution, a display device with higher display quality, a display device with improved viewing angle characteristics, or a flexible display device. Same-color subpixels are arranged in a zigzag pattern in a predetermined direction. In other words, when attention is paid to a subpixel, another two subpixels exhibiting the same color as the subpixel are preferably located upper right and lower right or upper left and lower left. Each pixel includes three subpixels arranged in an L shape. In addition, two pixels are combined so that pixel units including subpixel are arranged in matrix of 3×2.

Abstract: An optical power monitoring device that monitors power of input light reflected back into an optical fiber among output light output from the optical fiber, the optical power monitoring device includes: a photodetector disposed by the optical fiber that detects Rayleigh scattered light generated by the input light and the output light that are guided by the optical fiber; and a calculator that performs a calculation to exclude a component that corresponds to an output of the output light detected by the photodetector using first information that indicates a relationship between an output of the output light obtained in advance under a condition where the output light is not reflected and the output of the output light detected by the photodetector.

Abstract: An optical power monitoring device that monitors power of input light reflected back into an optical fiber among output light output from the optical fiber, the optical power monitoring device includes: a photodetector disposed by the optical fiber that detects Rayleigh scattered light generated by the input light and the output light that are guided by the optical fiber; and a calculator that performs a calculation to exclude a component that corresponds to an output of the output light detected by the photodetector using first information that indicates a relationship between an output of the output light obtained in advance under a condition where the output light is not reflected and the output of the output light detected by the photodetector.

Abstract: A gas detector includes: an infrared camera that images a gas; and a controller including at least an electronic component, wherein the controller determines a temperature range of the infrared camera in which the gas can be imaged, and detects the gas from moving infrared images taken for a predetermined period of time in the temperature range determined.

Abstract: A laser system 100 includes: a laser module 10 including: a DFB laser 12 that oscillates a laser beam 24; a heater 14 that adjusts a temperature of the DFB laser 12; and a harmonic generation element 18 that converts the laser beam 24 into a harmonic beam 34 of the laser beam 24; and a control unit 40 that modulates a wavelength of the laser beam 24, detects a detection signal synchronized with a modulation signal used for the modulation from an intensity of the harmonic beam 34, and controls a value of a heater current 28 to be injected to the heater 14 so as to reduce an amplitude of the detection signal.

Abstract: The present invention relates to controlling wavelength switching in a plurality of nodes that are provided to increase the distance of signal transmission in inverse MUX transmission in which a high-speed line is divided into a plurality of low-speed lines for transmission. A maximum skew occurring between adjacent nodes is measured, and switching of wavelength channels is performed in one or a plurality of nodes on the basis of the measured maximum skew to keep the skew of the entire inverse MUX transmission system at or below a prescribed value. The optical communication device is provided with an NNI functional block to which high-speed lines on the transmission channel side are connected, and a UNI functional block to which low-speed lines on the client side are connected.

Abstract: A small, low cost, low power-consumption optical receiver transmits signals at a high bit rate of approximately 10 Gbps over a long distance of 100 km or longer without chromatic dispersion compensation. An optical filter with a variable filtering wavelength is provided in the optical waveguide. A frequency-modulated signal light is inputted into the waveguide and transferred to the through port and the drop port thereof. The filter limits the frequency-modulated signal light to a predetermined frequency band and converts the said light to an intensity-modulated signal. The first and second converters provided at the through and drop ports to convert the first and second components of the intensity-modulated signal to electric signals, respectively. The filtering wavelength of the filter is controlled using the electric signals from the first and second converters. The input signal is regenerated from the electric signal of the second converter.

Abstract: In an optical wavelength control circuit, an activation control circuit outputs an optical output setting signal to a laser unit to set its optical output, and simultaneously outputs a temperature setting signal and a wavelength setting signal. A temperature error detection circuit outputs a temperature error signal. A wavelength error detection circuit outputs a wavelength error signal. A control switching circuit receives the temperature error signal and the wavelength error signal, selectively outputs the temperature error signal as a control error signal in the activation operation, and selectively outputs the wavelength error signal as the control error signal in a steady-state operation after the activation operation. A steady-state error removing circuit removes a steady-state error contained in the control error signal and outputs a temperature controller control signal.

Abstract: The present invention relates to controlling wavelength switching in a plurality of nodes that are provided to increase the distance of signal transmission in inverse MUX transmission in which a high-speed line is divided into a plurality of low-speed lines for transmission. A maximum skew occurring between adjacent nodes is measured, and switching of wavelength channels is performed in one or a plurality of nodes on the basis of the measured maximum skew to keep the skew of the entire inverse MUX transmission system at or below a prescribed value. The optical communication device is provided with an NNI functional block to which high-speed lines on the transmission channel side are connected, and a UNI functional block to which low-speed lines on the client side are connected.

Abstract: A small, low cost, low power-consumption optical receiver transmits signals at a high bit rate of approximately 10 Gbps over a long distance of 100 km or longer without chromatic dispersion compensation. An optical filter with a variable filtering wavelength is provided in the optical waveguide. A frequency-modulated signal light is inputted into the waveguide and transferred to the through port and the drop port thereof. The filter limits the frequency-modulated signal light to a predetermined frequency band and converts the said light to an intensity-modulated signal. The first and second converters provided at the through and drop ports to convert the first and second components of the intensity-modulated signal to electric signals, respectively. The filtering wavelength of the filter is controlled using the electric signals from the first and second converters. The input signal is regenerated from the electric signal of the second converter.

Abstract: An optical transmitting apparatus includes an optical filter, a port that monitor light transmitted through the optical filter, a port that monitor not light transmitted through the optical filter, an optical waveguide substrate on which the optical filter and an optical waveguide which includes a port that monitors the characteristic of the light which passes through the optical filter, a semiconductor laser and a heater that is capable of independently adjust the wavelength characteristic of any of the optical waveguide and the semiconductor laser, and the optical waveguide substrate and the semiconductor laser are integrated such that the temperature of the optical waveguide substrate and the semiconductor laser can be collectively adjusted.

Abstract: In a communication apparatus and the like, the line diagnosis using a test signal is conducted with higher precision. A test signal transmitter generates a test signal for a line diagnosis to feed the signal to a test signal multiplexer. The multiplexer multiplexes the test signal with a main signal to deliver the resultant signal to a clock and data regenerator (CDR) module, a main signal transmitter, a main signal receiver, a test signal separator, and a test signal receiver that are arranged on a communication line through which the main signal is transferred. In the operation, a controller accomplishes a control operation such that the bit rate of the test signal is more than that of signals for communication to thereby intentionally cause bit errors. This improves precision in the measurement of the bit error rate required for the line diagnosis.

Abstract: This invention provides a technique for realizing low-cost optical signal waveform monitoring with improved realtimeness to be applied to signal quality monitoring in an actual optical transmission system, and a technique for stably controlling an optical transmitter/receiver and various compensators by means of this waveform monitoring. Opening/closing of a optical gate is controlled by means of a clock signal synchronized with an optical signal input from a photocoupler and having a period equal to the bit interval of data or N (N: a positive integer) times longer than the bit interval to allow each pulse of the optical signal for one bit of data to pass through the optical gate for only part of the time width of the gate. A photoelectric conversion element to which the optical signal transmitted through the optical gate for only part of the time width obtains an average light intensity of the input optical signal. Information on this average light intensity is output to a monitoring output section.

Abstract: A wavelength stabilized laser module is provided which is so configured as to be simplified and smaller in size and is capable of emitting semiconductor laser light whose wavelength is stablized with high accuracy. The wavelength stablized laser module includes a semiconductor laser, a substrate, a lens to convert emitted semiconductor laser light to parallel luminous flux, a first photoelectric converter to receive a part of the parallel luminous flux and to convert it to electric signals, a filter to receive a part of the parallel luminous flux, a second photoelectric converter to receive light transmitted through the filter and to convert it to electric signals, wherein a control signal to be used for stabilization obtained by computations of electric signals fed from the converters is fed back to the semiconductor laser device and/or the substrate so that said semiconductor laser is able to stably emit laser light having a reference wavelength to be used as a target for stabilization.

Abstract: This invention provides a technique for realizing low-cost optical signal waveform monitoring with improved realtimeness to be applied to signal quality monitoring in an actual optical transmission system, and a technique for stably controlling an optical transmitter/receiver and various compensators by means of this waveform monitoring. Opening/closing of a optical gate is controlled by means of a clock signal synchronized with an optical signal input from a photocoupler and having a period equal to the bit interval of data or N (N: a positive integer) times longer than the bit interval to allow each pulse of the optical signal for one bit of data to pass through the optical gate for only part of the time width of the gate. A photoelectric conversion element to which the optical signal transmitted through the optical gate for only part of the time width obtains an average light intensity of the input optical signal. Information on this average light intensity is output to a monitoring output section.

Abstract: In a semiconductor laser diode module including a semiconductor laser diode having a front facet for emitting a light beam, a collimating lens for receiving the light beam to generate a collimated light beam and a coupling lens for receiving the collimated light beam and converging the collimated light beam to an optical fiber, a bandpass filter is provided for receiving a first part of the collimated light beam, and a light detector is provided to have a first portion for receiving the first part of the collimated light beam through the bandpass filter and a second portion for receiving a second part of the collimated light beam. Thus, a wavelength of the semiconductor laser diode is controlled in accordance with an output signal of the first portion of the light detector, and a light intensity of the semiconductor laser diode is controlled in accordance with an output signal of the second portion of the light detector.

Abstract: In a semiconductor laser diode module including a semiconductor laser diode having a front facet for emitting a light beam, a collimating lens for receiving the light beam to generate a collimated light beam and a coupling lens for receiving the collimated light beam and converging the collimated light beam to an optical fiber, a bandpass filter is provided for receiving a first part of the collimated light beam, and a light detector is provided to have a first portion for receiving the first part of the collimated light beam through the bandpass filter and a second portion for receiving a second part of the collimated light beam. Thus, a wavelength of the semiconductor laser diode is controlled in accordance with an output signal of the first portion of the light detector, and a light intensity of the semiconductor laser diode is controlled in accordance with an output signal of the second portion of the light detector.

Abstract: A semiconductor photonic element is provided, which realize low threshold current and satisfactory characteristics in the high temperatures and/or high output operating condition.