摘要:
An optical demultiplexer comprises a clock regenerating circuit for regenerating a clock signal for each optical signal channel from an optical multiplexed signal. An optical switch separates each optical signal channel from the optical multiplexed signal in accordance with the clock signal regenerated by the clock regenerating circuit. An identification information extraction circuit extracts identification information contained in each optical signal channel separated by the optical switch. A control circuit changes output destinations so that each optical signal channel is output to a designated destination in accordance with the identification information extracted by the identification information extraction circuit. The identification information is appended as identification data to a data signal represented by the optical signal, and the identification information extraction circuit extracts the identification data contained in the data signal reconstructed from each optical signal channel. A signal switching circuit is provided between outputs of the optical switch and output destinations, wherein the control circuit changes output destinations by changing connection relationships in the signal switching circuit between the outputs of the optical switch and the output destinations, for example, by changing the phase of the clock signal supplied to the optical switch.
摘要:
Disclosed is an optical control device which has a LiNbO3 or LiTaO3 crystalline substrate having electrooptic effect; a channel-type optical waveguide which is formed in the crystalline substrate by doping metal; an optically transparent film layer formed on the crystalline substrate; and electrodes formed on the optically transparent film layer; wherein the crystalline substrate has a surface except a region which waveguided-light through the channel-type optical waveguide propagates or an entire surface under which a layer doped by metal is formed.
摘要:
A supervisory and control signal transmitting system for use in an optically amplifying repeater system amplifies attenuated light and for transmitting data over a long distance between a transmitting station and a receiving station through a plurality of repeaters. The supervisory and control signal transmitting system comprises a sub signal superimposing portion for superimposing both a sub signal with a carrier frequency modulated by a supervisory and control signal and a modulation factor stabilizing signal with a different frequency thereof on an optical main signal modulated corresponding to transmission data, a transmitter sub signal superimposing portion for monitoring the output of the sub signal superimposing portion and for controlling the sub signal superimposing portion so as to stabilize the modulation factor of the sub signal to be superimposed, a modulating portion for receiving the output of the transmitter sub signal superimposing portion, and a stabilizing signal erasing portion for monitoring the output of the modulating portion, for extracting the frequency component of the modulation factor stabilizing signal, and for driving the modulating portion so as to erase the stabilizing signal from the output of the modulating portion.
摘要:
An optical transmitter operates on the DPSH-IM (direct phase-shift and self-homodyne intensity modulation) principle. The optical transmitter slightly amplitude-modulates the modulation current of a laser diode using a low frequency signal and detects the modulated component from the optical output. These features stabilize the operating point and improve the transmission waveform.
摘要:
An optical control device such as an optical switch includes two waveguides formed in an electrooptical substrate. Two control electrodes are preferably formed respectively above the two waveguides through a buffer layer. The optical control device is further provided with additional electrodes formed where there is no waveguide therebelow. The additional electrodes are connected with either of the two control electrodes, so that there generates an electric field not only in the direction vertical to the surface of the substrate but in the direction parallel to the surface thereof.
摘要:
A Mach-Zehnder interferometer type modulator, constructed of first and second optical waveguides, first and second electrodes cooperating with the same, and a driving voltage source, wherein a driving voltage source is constructed of first and second driving units which drive independently the first and second electrodes in accordance with a data input and wherein the first and second driving units apply first and second driving voltages, individually determined, to the first and second electrodes.
摘要:
An optical control device comprises optical waveguides provided on a substrate having an electrooptic effect, a buffer layer provided on the substrate to cover the optical waveguides, and control electrodes provided on the buffer layer for applying a predetermined voltage across the optical waveguides. The optical waveguides has a coupling portion, at which an interval of the optical waveguides is narrowed. In this optical control device, a distortion dispersing structure is provided in the vicinity of the control electrodes to disperse distortion locally accumulated in the vicinity of the control electrodes to the whole area of the substrate uniformly.
摘要:
An integrated circuit device including a stacked layer unit having a plurality of stacked layers each having an insulation layer and at least one conductive layer strip formed on a surface of the insulation layer, and at least one chip mounted on the top of the insulation layer and having a plurality of circuit elements. The IC device also includes at least one first conductive member formed in the stacked layer unit, having a low inductance for first signals applied thereto and operatively connecting the first signals to be transferred between the circuit elements. The IC device further includes at least one second conductive member formed in the stacked layer unit, having a higher inductance for the first signals than that of the first conductive member and operatively connecting second signals to be transferred between the circuit elements the stacked layer unit, the chip, and the first and second conductive members are enclosed by a package and sealed with a hermetic seal.