Abstract: A transport device includes a transport path that includes an opening through which a developer flows into the transport path, an opening and closing portion that is provided to be movable along the transport path and that opens and closes the opening, and a transport body that is disposed in the transport path, that includes a blade formed in a spiral shape on an outer periphery of a shaft portion, that transports the developer flowing into the transport path through the opening and moves the opening and closing portion to an opening position with the blade by rotating forward, and that idly rotates with respect to the opening and closing portion moved to the opening position in a case of forward rotation.

Abstract: 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.

Abstract: An optical device includes a generator, a light emitter, a modulator, an optical amplifier, a current source, a storage, and a controller. The generator generates an electric signal of a multilevel amplitude modulation method. The light emitter emits laser light. The modulator modulates the laser light using the electric signal and outputs an optical signal. The optical amplifier optically amplifies the modulated optical signal according to a drive current. The current source adjusts the drive current to be supplied to the optical amplifier. The storage previously stores an information with respect to input-output characteristics of the optical signal in the optical amplifier relative to drive current value of the drive current. The controller acquires, from the storage, the input-output characteristics corresponding to the drive current value of the drive current supplied to the optical amplifier and controls the electric signal based on the acquired input-output characteristics.

Abstract: An optical transmission module includes a photonic integrated circuit, a processor that controls the power state of the photonic integrated circuit, and a current source circuit that supplies electric current to a light source used for the photonic integrated circuit. The photonic integrated circuit has an optical multiplexer block including a plurality of multiplexers connected in a n-level tree structure (n is an integer greater than 1), 2{circumflex over (?)}n optical modulators connected to inputs of the optical multiplexer block, and a photodetector connected to an input or an output of each of the plurality of the multiplexers. The light source emits a light beam to be incident onto a corresponding one of the 2{circumflex over (?)}n optical multiplexers. The processor controls the current source circuit for each of the plurality of the multiplexers, based on the monitored value acquired from the photodetector provided to each of the plurality of the multiplexers.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.