Fujitsu Corporation

Canon Kabushiki Kaisha

Takashi Tsuda

Kazuo Yamane

Yumiko Kawasaki

Satoru Okano

Yasunori Nagakubo

Kazuhiro Suzuki

Hiroshi Nishimoto

Masakazu Mori

Yoshinori Ohkuma

Shinya Inagaki

Tetsuo Ishizaka

Noriaki Mizuguchi

Setsuo Misaizu

Hisashi Takamatsu

Manabu Komiyama

Shunichi Sato

Toshio Ohya

Saeko Yokoi

Junya Fukumoto

Yuma Kudo

Tsukasa Takahashi

Yuji Tamura

Hiroyuki Itou

Michikazu Shima

Hisaya Sakamoto

Hiroyuki Iwaki

Yuji Miyaki

Sadao Ibukuro

Makoto Murakami

Sunao Itou

Tooru Matsumoto

Akihiko Hayashi

Keisuke Imai

Kazuto Imai

Michinao Kawano

Tomoko Anzai

Tooru Shima

According to one embodiment, an imaging apparatus includes an image sensor, image generation circuitry, calculation circuitry and superimposition circuitry. The image generation circuitry successively generates a first image and a second image. The calculation circuitry calculates a first parameter to allow brightness of the first image to be equal to or close to a predetermined value, and calculates a second parameter relating to brightness of the second image based on the first parameter and a predetermined ratio. The superimposition circuitry generates a composite image by superimposing the second image in which the brightness is adjusted using the second parameter onto the first image in which the brightness is adjusted using the first parameter.

Imaging apparatus and imaging method

An imaging device according to an embodiment includes an image sensor, and processing circuitry. The image sensor is a rolling-shutter type image sensor that includes a plurality of pixels that are arranged in a matrix and generate an electric signal due to light received and, on a frame-to-frame basis, repeatedly performs a process to sequentially start to conduct exposure on at least every line, starting from the first line of the pixels to the last line, and output the electric signal sequentially from the line for which exposure has been completed. The processing circuitry causes the pixels to receive light during only a period based on the blanking period that corresponds to the period from when the output of the electric signal from the last line is finished until the output of the electric signal from the first line is started. The processing circuitry generates images in accordance with the electric signal.

Imaging device and control method

Both wavelength dispersion and a dispersion slope of a line fiber are simultaneously compensated for by combining two types of dispersion compensators having different characteristics.

Apparatus and method of compensating for wavelength dispersion of optical transmission line

The invention provides a wavelength multiplexing transmission apparatus includes a plurality of optical signal outputting sections for outputting optical signals having different wavelengths from each other, and a wavelength multiplexing section for wavelength multiplexing the optical signals outputted from the optical signal outputting sections and sending out a resulting optical signal. Each of the optical signal outputting sections includes a transmission light source driven by an electric signal for outputting an optical signal of a predetermined wavelength, and a wavelength filter capable of passing therethrough and sending out only an optical signal of the predetermined wavelength to be outputted from the transmission light source to prevent a wavelength drift of the optical signal outputted from the transmission light source. A variation of the wavelength of the transmission light source is detected, and the transmission light source is shut down in order to prevent otherwise possible crosstalk with another channel and prevent a further influence of the same.

Wavelength multiplexing transmission apparatus and wavelength demultiplexing reception apparatus

An optical fiber transmission line composed of a plurality of segments each having a length falling within a predetermined range is provided. An optical transmitter for supplying an optical signal to the transmission line is provided at one end of the transmission line. An optical receiver for receiving the optical signal from the transmission line is provided at the other end of the transmission line. An optical amplifier is provided between any two adjacent ones of the segments. A dispersion compensator is provided in association with each of the optical transmitter, the optical receiver, and the optical amplifier. The dispersion compensator provides a dispersion selected from a plurality of stepwise varying dispersions determined according to the predetermined range.

Method and system for optical transmission adopting dispersion compensation

The invention, relates to a method for optical fiber communication. An optical signal having chirping determined by a chirp parameter is output to an optical fiber transmission line. The optical signal transmitted by the optical fiber transmission line is converted into an electrical signal. A bit error of the electrical signal is detected. Then, the chirp parameter is controlled so that the bit error detected above is reduced. According to this method, the chirp parameter is controlled so that the bit error detected is reduced. Accordingly, a chirping occurring in the optical fiber transmission line can be suppressed by the chirping of the optical signal to be output to the optical fiber transmission line, thereby compensating for chromatic dispersion and nonlinearity.

Method for optical fiber communication, and device and system for use in carrying out the method

The invention relates to a method of activating an optical communication system comprising a plurality of optical amplifiers having an optical amplifier, between optical transmission lines in which wavelength-division multiplex optical signals are transmitted. The method comprises steps of: generating a desired slope in a desired wavelength range of a gain wavelength curve of the optical amplifier; adjusting an output of the optical amplifier to a desired output level; performing the above two steps in a plurality of optical repeater stations, the steps being carried out in sequence from the first to the last optical repeater stations; and adjusting a level in each optical signal in the wavelength-division multiplex optical signal so as to have substantially constant optical signal-to-noise ratios in the optical signals to be received. Activating the optical communication system according to this procedure allows proper execution of gain slope compensation, output control, and pre-emphasis control.

Method of activating optical communication system, channel increasing/decreasing method, and computer-readable recording medium

The present invention relates to a method for optical fiber communication, and a terminal device and system for use in carrying out the method, and an object of the present invention is to compensate for chromatic dispersion and nonlinearity. A device for outputting an optical signal having a variable optical power into an optical fiber transmission line is provided. The optical signal transmitted by the transmission line is converted into an electrical signal by an optical receiver. A parameter related to waveform degradation of the electrical signal is detected by a monitor unit. A control unit controls the optical power of the optical signal to be output from the device so that the waveform degradation is improved.

Method for optical fiber communication, and terminal device and system for use in carrying out the method

The present invention relates to an optical transmission device and an optical communication system applied to wavelength division multiplexing (WDM). The optical transmission device includes an optical multiplexer for wavelength division multiplexing a plurality of optical signals to generate WDM signal light and outputting the WDM signal light to an optical transmission line, a detecting unit for detecting a break of each optical signal according to the power of each optical signal, and a compensator for adding light having a predetermined wavelength to the WDM signal light when at least one of the optical signals is cut off. Through the structure of the present invention it becomes possible to prevent a deterioration in transmission quality in the case that the number of WDM channels is changed.

Optical transmission device and optical communication system

The present invention relates to an optical amplifier and an optical communication system applied to WDM (wavelength division multiplexing). The optical amplifier includes an optical amplifying medium to which WDM signal light obtained by wavelength division multiplexing a plurality of optical signals having different wavelengths is supplied, a pumping unit for pumping the optical amplifying medium such that the medium gives a gain to the WDM signal light, a feedback loop for controlling the pumping unit so that the gain is maintained constant, and an optical attenuator for giving a variable attenuation to the WDM signal light. Through the structure of the present invention, it becomes possible to provide an optical amplifier which can maintain constant the optical output level per channel of WDM and can maintain the gain characteristic constant.

Optical amplifier and optical communication system having the optical amplifier

An optical amplifier relates to WDM (wavelength division multiplexing). The optical amplifier includes an optical amplifying unit, an ALC (automatic output level control) circuit for controlling the unit based on the output level thereof, and AGC (automatic gain control) circuit for controlling the unit based on the input and output levels thereof. A selecting circuit alternatively selects and operates the ALC and AGC circuits in accordance with a predetermined rule. Accordingly, the inconvenience occurring in the case of performing only one of ALC and AGC can be eliminated.

Optical amplifier and optical transmission system including the optical

A Peltier control circuit detects a temperature of a device combined with a Peltier device and controls a current flowing through the Peltier device so as to keep the temperature of the device at a predetermined value. The circuit has a temperature sensing section for detecting the temperature of a device, a comparing section for comparing a temperature detection value with a predetermined temperature reference value, a limiting section for providing a comparison output with the limitation of a current flowing through the Peltier device and providing the limitation with a predetermined temperature characteristics, and a driving section for providing the Peltier device with an input or output driving current in accordance with the comparison output via the limiting section.

Peltier control circuit and a peltier device structure

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Kawasaki, Japan

Takashi Tsuda