Abstract: An optical packet network system of a ring type, capable of preventing degradation of an optical signal, can be implemented by providing a mechanism relatively simple in structure, capable of erasing light noise if the optical packet signal does not exists. In the optical packet network system made up by interconnecting respective nodes adjacent to each other, and connecting a sending source of an optical packet signal to a ring, a light noise removal function block is provided between the respective nodes adjacent to each other.

Abstract: An optical communication apparatus includes an erbium-doped optical fiber amplifier for amplifying a modulated optical signal, wherein a light which is not modulated is inputted to the erbium-doped optical fiber amplifier together with the optical signal.

Abstract: A fine vacuum tube element and other electronic elements are integrated and formed on a semiconductor substrate, and the fine vacuum tube element and the other electronic elements transmit signals to and from each other. When integrating the vacuum tube element with the other electronic elements, a quantum effect is realized in a room temperature environment by utilizing ballistic electrons (non-scattering electrons) traveling through the vacuum, and in the integrated circuit, an A/D converter is constructed by an interference system such as a Mach-Zehnder interferometer. Also an integrated circuit of an advanced function-integrated type is provided, comprising an interference system such as a Mach-Zehnder interferometer wherein weighting of the Mach-Zehnder interferometer is constituted for image processing and signal code conversion.

Abstract: A clock reproducing apparatus includes a clock reproducing circuit having: a gated oscillator having an oscillating circuit of two routes; and a frequency control circuit for comparing a phase of an output of the gated oscillator with a phase of a reference clock, and supplying a phase control signal to the gated oscillator based on the comparison result so as to set a delay time, input data is input to a reset input terminal of the gated oscillator, and different route of the two routes of the oscillating circuit operates depending on a case where the input data is “H” and a case where the input data is “L”.

Abstract: A clock reproducing apparatus includes a clock reproducing circuit having: a gated oscillator having an oscillating circuit of two routes; and a frequency control circuit for comparing a phase of an output of the gated oscillator with a phase of a reference clock, and supplying a phase control signal to the gated oscillator based on the comparison result so as to set a delay time, input data is input to a reset input terminal of the gated oscillator, and different route of the two routes of the oscillating circuit operates depending on a case where the input data is “H” and a case where the input data is “L”.

Abstract: An optical waveform shaping device includes a first waveguide portion, formed on a substrate, for transmitting the optical signal and simultaneously absorbing a portion of the optical signal, which has a signal level equal to or smaller than a predetermined value, so as to shape the optical signal; and a second waveguide portion, formed on the substrate, for transmitting the optical signal, which was transmitted through the first waveguide portion, and simultaneously amplifying the optical signal. The first waveguide portion may be formed using a saturable absorber. A first electrode for supplying electric current to the first waveguide portion so that the first waveguide portion is provided with a function of absorbing the optical signal; and a second electrode for supplying electric current to the second waveguide portion so that the second waveguide portion is provided with a function of amplifying the optical signal may also be provided.

Abstract: An optical switch changes over transmission paths of an optical signal by a refractive index change. The optical switch has an optical waveguide layer having an optical waveguide whose output path of an optical signal branches into two, and reflection diffusing ditches which are provided in a portion outside the optical waveguide in the optical waveguide layer, wherein the portion is closed to a branch portion of the optical waveguides. The reflection diffusing ditches extend in a direction crossing a traveling direction of the optical signal.

Abstract: An optical switch in which the adverse effect of heating can be restrained is realized.

Abstract: An optical sampling apparatus has an electron beam generating apparatus which generates an electron beam by irradiating a cathode with an optical signal, a deflection electrode which deflects the generated electron beam, a sampling slit which transmits a part of the deflected electron beam, and a charge detection section which detects the quantity of charges or accumulated current of the transmitted electron beam. It is possible to perform accurate sampling in a high band.

Abstract: A clock reproducing apparatus includes a clock reproducing circuit having: a gated oscillator having an oscillating circuit of two routes; and a frequency control circuit for comparing a phase of an output of the gated oscillator with a phase of a reference clock, and supplying a phase control signal to the gated oscillator based on the comparison result so as to set a delay time, input data is input to a reset input terminal of the gated oscillator, and different route of the two routes of the oscillating circuit operates depending on a case where the input data is “H” and a case where the input data is “L”.

Abstract: An optical communication apparatus includes: an erbium-doped optical fiber amplifier for amplifying a modulated optical signal, wherein a DC (direct current) light which is not modulated is inputted to the erbium-doped optical fiber amplifier together with the optical signal.

Abstract: An optical packet network system of a ring type, capable of preventing degradation of an optical signal, can be implemented by providing a mechanism relatively simple in structure, capable of erasing light noise if the optical packet signal does not exists. In the optical packet network system made up by interconnecting respective nodes adjacent to each other, and connecting a sending source of an optical packet signal to a ring, a light noise removal function block is provided between the respective nodes adjacent to each other.

Abstract: A photoelectric apparatus has a phototransistor which receives a light signal and in which a collector current thereof varies according to intensity of the received light signal, and a transistor in which a collector current thereof varies according to a base voltage thereof. The phototransistor and the transistor constitute a differential amplification circuit. At least one of the phototransistor and the transistor outputs an electric signal.

Abstract: An optical AND element includes a semiconductor laser having a plurality of saturable absorption regions on an optical waveguide, electrodes of the saturable absorption regions being separated from each other, and a light inputting section for inputting light into the respective saturable absorption regions.

Abstract: An optical waveform shaping device includes a first waveguide portion, formed on a substrate, for transmitting the optical signal and simultaneously absorbing a portion of the optical signal, which has a signal level equal to or smaller than a predetermined value, so as to shape the optical signal; and a second waveguide portion, formed on the substrate, for transmitting the optical signal, which was transmitted through the first waveguide portion, and simultaneously amplifying the optical signal. The first waveguide portion may be formed using a saturable absorber. A first electrode for supplying electric current to the first waveguide portion so that the first waveguide portion is provided with a function of absorbing the optical signal; and a second electrode for supplying electric current to the second waveguide portion so that the second waveguide portion is provided with a function of amplifying the optical signal may also be provided.

Abstract: A matrix optical switch that can switch the transmission path of an optical signal without requiring a driving unit for each optical switch is realized. A matrix optical switch for switching a transmission path of an optical signal by connecting plural input sides and plural output sides, respectively, comprises: a semiconductor optical waveguide substrate; a photo mask choosing system for selecting and arranging one photo mask from plural photo masks each of which has printed thereon a pattern connecting plural input sides to plural output sides; and a light source for casting output light having larger energy than a band gap of the semiconductor optical waveguide substrate onto a photon injection area between the plural input sides and the plural output sides on the semiconductor optical waveguide substrate via the selected photo mask.

Abstract: An optical router capable of efficiently allocating optimum optical paths to optical signals at optimum timings is provided in accordance with the present invention. The optical router is capable of delaying a plurality of the optical signals containing routing information attached to the header parts thereof. The optical router contains an optical switch which has a plurality of input and output ports; an optical-electrical converter for converting a plurality of the optical signals to electrical signals; memory wherein path control information and delay time information are stored; and a controller for generating an electrical routing control signal which can change the optical path of the optical signals by finding the path control information according to the routing information extracted from the output of the optical-electrical converter and which can delay the electrical routing control.

Abstract: An optical switch changes over transmission paths of an optical signal by a refractive index change. The optical switch has an optical waveguide layer having an optical waveguide whose output path of an optical signal branches into two, and reflection diffusing ditches which are provided in a portion outside the optical waveguide in the optical waveguide layer, wherein the portion is closed to a branch portion of the optical waveguides. The reflection diffusing ditches extend in a direction crossing a traveling direction of the optical signal.

Abstract: When a voltage is applied to plural spot electrodes selected from the spot electrodes arranged in the matrix form and the light incident on the two-dimensional plane waveguide is reflected by at least two parallel lines, the refractive index of the optical waveguide is partly changed so that the wavelength of the light, the angle of the two lines to the incident light and the distance between the lines satisfy the Bragg reflection condition.

Abstract: A microreactor has a plurality of flow channels, a joint flow channel where the plurality of flow channels are joined, a light applying section which applies light, that accelerates a reaction of fluids which flows through the plurality of flow channels to join in the joint flow channel, to the joint flow channel; and an applying section which applies a magnetic field and/or an electric field to a reaction production substance.