摘要:
An optical receiving apparatus is provided which is constructed to compensate for a rise in offset level attributable to low-frequency response of a light-receiving device. An offset detecting circuit detects a quantity of electricity indicative of an offset current quantity which corresponds to the zero level of an optical signal within the current quantity output from the light-receiving device, and a current subtracting circuit reproduces the offset current quantity based on the detected quantity of electricity, subtracts the reproduced offset current quantity from the current quantity output from the light-receiving device, and supplies the result to a preamplifier.
摘要:
An optical switch includes plural ports aligned; a spectroscopic element that divides a light input to one of the ports that is an input port; plural mirrors that are aligned in a spectral direction of the light divided, and reflect the light divided; and a control unit that changes an angle of each of the mirrors so that the light reflected is output to one of the ports that is an output port, and shifts the angle in the spectral direction and a direction perpendicular to the spectral direction to attenuate the light output from the output port.
摘要:
A method for controlling power in a computer system having a network device and a wakeup function is disclosed. A determination is made whether or not the network device is in an associated state at the time when the computer system moves into a power saving mode. In response to a determination that the network device is not in the associated state, power supply is turned off from a power source to the network device. In response to a determination that the network device is in the associated state, power supply is continually provided from the power source to the network device.
摘要:
An optical device includes: an optical component; a case air-sealed, and made of metal, the optical component being secured within the case; and a lens provided within the case, and positionally adjusted in consideration of a deformation of the case air-sealed, light emitted from the optical component passing through the lens or light traveling to the optical component passing through the lens.
摘要:
A protection IC connected to cell groups of a secondary battery assembly of a secondary battery connected in series and monitoring battery voltages of the cells in the cell groups, including terminals connected to connection points of the cells in the cell groups and both ends of the cell groups; a first alarm generating portion detecting an overvoltage by comparing voltages of the cells of the cell groups on both ends of the cells and generates the first alarm signal; and a second alarm generating portion detecting disconnection in connection points of the cells and disconnection between the connection points of the cell groups and the both ends and the terminals by detecting voltage drop or current decrement at the connection points of the cells of the cell groups and at one end of the cell groups in the cells, and generates a second alarm signal.
摘要:
A dispersion compensating apparatus compensates dispersion of an optical signal using reflection-type etalons. Each of the etalons reflects the optical signal and at least one etalon has, with respect to a group delay characteristic, a wavelength cycle and a finesse that are larger than those of the other etalons. Power supplies and temperature control units respectively shift, in terms of the wavelength, the group delay characteristics of the etalons.
摘要:
The present mirror device for suppressing PDL on the assumption of multiple modes of angles of input light and output light to movable mirrors with respect to the crystal axis of a crystal member at the time light passes through the crystal member. The mirror device includes a mirror system 2 and a flat-shaped crystal member 3 which is arranged in such a manner that a first angle is not larger than a second angle. The crystal member is constructed in such a manner that a third angle is substantially equal to a half of a fourth angle.
摘要:
An optical device used, for example, in an add/drop multiplexer, a dynamic gain equalizer or a optical power monitor. The optical device includes (a) a substrate; (b) a first slab waveguide formed on the substrate; (c) channel waveguides of differing lengths formed on the substrate, light output from the first slab waveguide being input to the channel waveguides; and (d) a second slab waveguide formed on the substrate, light output from the channel waveguides being input to the second slab waveguide. An end face of the second slab waveguide shares a face with an end face of the substrate. The optical device has low loss characteristics.
摘要:
A wavelength selective optical switch of the present invention separates a WDM light emitted from an input port of an input and output optical system, according to wavelengths, by a diffraction grating, and thereafter, condenses the lights of respective wavelengths on MEMS mirrors respectively corresponding to the respective wavelengths, in a mirror array, to reflect them by a condenser optical system, to thereby switch optical paths for the respective lights. The condenser optical system is configured by combining a plurality of lenses whose focal distances are different from each other, and positions in an optical axis direction of the lenses are adjustable by a slide mechanism. Thus, despite an error in the focal distances of the condenser lenses, in a mounting angle of a spectral element or the like, a beam pitch at the condensing positions of the lights of respective wavelengths can be coincident with a mirror pitch in the mirror array.
摘要:
A dispersion-slope compensator including a feedback-type optical filter constituted by a looped optical line; an input-and-output optical line which inputs and outputs optical signals; and optical couplers which couples the looped optical line and the input-and-output optical line at two or more positions so that a Mach-Zehnder interferometer is formed by a portion of the looped optical line and a portion of the input-and-output optical line which are located between two of the optical couplers. A portion of the optical path realizing an MZI arm which constitutes the Mach-Zehnder interferometer is spatially separated from the other portions of the optical path so that the optical length of the MZI arm can be variably adjusted, and an amount of compensation for dispersion slope can be variably set.