Nkk Corporation

Fujitsu Optical Components Limited

Hitachi Solutions, Ltd.

Fujitsu Corporation

Fuji Photo Film Company, Limited

Nec Corporation

Ricoh Company, Ltd.

Jfe Steel Corporation

Nippon Kokan Kabushiki Kaisha

Japan & Nippon Furnace Kogyo Kaisha, Ltd.

Toshio Ishii

Shunichi Sugiyama

Munehiro Ishioka

Nobuyuki Ishida

Seishi Hatakeyama

Kentaro Akashi

Teruhisa Kuwana

Yoichi Miyakawa

Kenji Araki

Naoki Kuwata

Shuzo Fukuda

Kazuo Kunioka

Akira Hiraya

Hitoshi Oishi

Toshihiko Ooi

Shinichi Tomonaga

Motoi Uesugi

Toshio Sato

Syu-ji Nomura

Yasunori Ohsaki

Tadashi Kawasaki

Kozo Hadada

Ryuji Nagayama

Keishi Yamashita

Kazumi Jiromaru

Hideyuki Suzuki

Takayuki Fukui

Hideyuki Takahashi

Makoto Ando

Hiroshi Ohmura

Hiroyuki Fukuda

Yuichi Watanabe

Hiroaki Sato

Yoshikazu Suzuki

Yoshihiko Kawai

Ryoichi Tanaka

Takashi Wada

Mamoru Matsuo

Michitaka Sakurai

Takefumi Adachi

Masayuki Nakada

Masaaki Tsuda

Naoki Nakata

Yoshiteru Kikuchi

Shinji Koseki

Akira Gamou

Yutaka Ohkubo

Akira Tonouchi

Takashi Maemori

Hidetoshi Matsuno

Makoto Miyata

Kazuhiko Imamura

Hoshihiko Toda

Masaru Sagiyama

Kenta Kannari

Masaru Akizawa

Katsuhiro Takebayashi

Toshikazu Akiyama

Yasuhisa Tajiri

Kazuhisa Kabeya

Kentaro Mori

Akira Yada

Kyohei Ishida

Eitaro Shidara

Shigeru Kano

Yoshiki Fujii

Shigeo Kurioka

Akinori Hokabori

Yutaka Okubo

Seiko Nara

Takashi Oosako

An optical transmission apparatus includes an emitter that emits an optical signal in accordance with a bias current, and a Mach-Zehnder optical modulator that optically modulates the optical signal in accordance with an electrical signal. The optical modulator includes a detector that detects a temperature inside the optical modulator, and a controller that, when detecting activation of a power supply, controls the temperature inside the optical modulator such that the temperature detected by the detector reaches a target temperature.

Optical transmission apparatus, optical modulator, and activation method

An optical receiver includes an optical amplifier that amplifies a received optical signal containing multiple wavelengths, a monitor circuit that monitors light intensities of the demultiplexed optical signal, a processor, and a memory having information representing a relationship between a total incident light intensity of the optical signal incident onto the optical amplifier and gains of the optical amplifier for the respective wavelengths. The processor repeats first calculation for determining the gains of the respective wavelengths from the memory, based on a drive current for driving the optical amplifier and an estimation value of the total incident light intensity of the optical signal, second calculation for calculating the incident light intensities of the respective wavelengths of the optical signal based on the gains and the monitored light intensities, and third calculation to calculate the total incident light intensity of the optical signal, until the total incident light intensity converges.

Optical receiver and optical transceiver module

An equalizer has a first tapped delay line in which N taps (N is a positive integer) are connected in cascade, a second tapped delay line having one tap and connected in parallel with the first tapped delay line, a first multiplier configured to multiply signals extracted from the N taps by corresponding coefficients, a second multiplier configured to multiply a signal output from the second tapped delay line by a second coefficient, and an adder configured to add products of the first multiplier and a product of the second multiplier. The first tapped delay line has a fixed delay, and the second tapped delay line has a variable delay changeable at a 1/M resolution of the fixed delay, where M is a number greater than 1.

Equalizer and communication module using the same

An optical communication apparatus includes a level detector, an FIR filter, and a adjustor. The level detector detects level information that discriminates a change in a multi-value level based on an input signal used in a multi-value amplitude modulation system. The FIR filter compensates a signal band of the input signal in accordance with tap coefficients of a plurality of multipliers. The adjustor corrects the tap coefficient of each of the multipliers included in the FIR filter based on the level information detected in the level detector.

Optical communication apparatus and correcting method

An optical module has an optical amplifier that amplifies an optical signal in which multiple wavelengths are multiplexed, an optical demultiplexer that separates the multiple wavelengths from the optical signal having been amplified by the optical amplifier, a first photodetector that monitors the optical signal at an input side of the optical amplifier, a second photodetector that monitors each of the multiple wavelengths at an output side of the optical demultiplexer, and a control circuit that controls a center wavelength of a filter of the optical demultiplexer based upon a first output from the first photodetector and a second output from the second photodetector.

Optical module and control method of controlling center wavelength of optical filter

An optical receiver includes photodetectors each provided on a corresponding channel of multiple channels and configured to detect an optical signal at the corresponding channel, a delay adjuster circuit provided before the photodetectors and configured to adjust a delay time of an optical waveform of an incoming signal on at least one channel, and a processor that controls the delay time such that a change point of a first optical waveform of a first channel is away from a data decision timing of a second optical waveform of a second channel, using information acquired from an electrical signal produced after photo-detection.

Optical receiver, optical transceiver using the same, and control method of reception of optical signals

An optical receiver includes a demultiplexer configured to demultiplex, for each channel, optical signals input through a plurality of channels, a photoelectric converter having a number of light receivers corresponding to the plurality of channels, the photoelectric converter being configured to convert an optical signal into an electric signal for each channel, a monitor circuit configured to monitor, for each channel, an amplitude characteristic of the optical signal converted into the electric signal by the photoelectric converter, and a control circuit configured to control, based on a monitored result of the monitor circuit, a bias voltage to be applied to the light receiver such that an amount of variability in the amplitude characteristic between the channels is minimum or falls within a predetermined range.

Optical receiver, optical transceiver, and optical signal reception control method

A batch annealing furnace includes a coil support base on which an end face of a coil is mounted and that supports the coil with an axis of the coil being upright, an inner cover that covers an entire body of the coil mounted on the coil support base, and a cooling pipe that extends downward from the upper part of the inner cover to a cavity of the inner peripheral part of the coil mounted on the coil support base and cools the coil from the inner surface side by passing a coolant through the inside of the cooling pipe.

Batch annealing furnace for coils

An optical transmitter includes an EA modulator, a photocurrent detection circuit, a modulator drive circuit, and a CPU. The EA modulator converts an input signal into an optical signal and outputs the optical signal. The photocurrent detection circuit detects an optical absorption current (a photocurrent) in the EA modulator. The modulator drive circuit controls the EA modulator. The CPU calculates a voltage to be applied to the modulator drive circuit based on the optical absorption current detected by the photocurrent detection circuit.

Optical transmitter and waveform compensation method

An optical transmitter includes: a modulator driver to generate a drive signal from an input signal; a modulator to generate a modulated optical signal according to the drive signal; an amplitude detector to detect an input amplitude representative of an amplitude of the input signal; and a controller to generate a waveform control signal according to the input amplitude detected by the amplitude detector. The modulator driver controls a waveform of the drive signal according to the waveform control signal.

Optical transmitter and method for optical signal waveform compensation

Digitizer for interactive white board

Reflective bar for interactive whiteboard

Digitizer for interactive whiteboard

Reflective pen for interactive white board

A housing in which a heat source for heating a member to be heated is disposable includes a first end and a second end in a longitudinal direction. Each of the first end and the second end is linked to a duct. A blowing unit is provided at the first end of the housing and causes an airflow in a space formed in a state in which the heat source is disposed in the housing. The duct linked to the second end of the housing is formed to extend from the second end. A length of the duct linked to the second end of the housing is longer than a hydraulic diameter by a predetermined number of times or more.

Heat exhausting structure and image forming apparatus

Growing community of inventors

Tokyo, Japan

Toshio Ishii