FUJITSU OPTICAL COMPONENTS LIMITED Patent applications |
Patent application number | Title | Published |
20160142131 | OPTICAL TRANSMITTER MODULE - An optical transmission device includes a light source, a driver, and a light receiving element. In accordance with electronic signals supplied from a signal line, the light source emits forward a signal light and emits back a monitor light for monitoring the signal light. The driver is disposed behind the light source and supplies the electronic signals to the signal line. The driver has a reflection area that reflects the monitor light in a direction different from a direction in which the monitor light, which is emitted back from the light source in accordance with the electronic signal, travels. The light receiving element receives the monitor light that is reflected on the reflection area of the driver. | 05-19-2016 |
20160141832 | LASER APPARATUS AND OPTICAL TRANSMITTER - A laser apparatus includes a semiconductor laser of which a drive condition is controlled according to a plurality of types of drive currents and a controller which controls the drive condition such that a sum of the drive currents is equal to or less than a predetermined threshold value. | 05-19-2016 |
20160065310 | OPTICAL COMMUNICATION APPARATUS AND METHOD OF CONTROLLING OPTICAL MODULATOR - An optical communication apparatus includes an optical modulator having a Mach-Zehnder interferometer with a pair of waveguides and configured to modulate a phase of light emitted from a light source, a first controller configured to control a first substrate bias voltage or an amplitude of a first drive signal applied to a first waveguide of the waveguide pair of the optical modulator based upon an output of the optical modulator or a wavelength of the light source; and a second controller configured to control a second substrate bias voltage or an amplitude of a second drive signal applied to a second waveguide of the waveguide pair of the optical modulator independently from the first controller, based upon the output of the optical modulator or the wavelength of the light source. | 03-03-2016 |
20160064897 | SEMICONDUCTOR LASER - A semiconductor laser includes a semiconductor substrate, an active region provided over the semiconductor substrate and having an active layer and a first diffraction grating, and a guiding region provided over the semiconductor substrate and having a guiding layer continuously extending from the active layer in an optical axis direction and a second diffraction grating continuously extending from the first diffraction grating in the optical axis direction. A grating period of the second diffraction grating is uniform, the first diffraction grating has a first part in which a grating period becomes uneven, and a grating formation density of the first diffraction grating is smaller than the grating formation density of the second diffraction grating. | 03-03-2016 |
20160056897 | OPTICAL COMMUNICATION DEVICE AND METHOD OF CONTROLLING OPTICAL MODULATOR - An optical communication device has a Mach-Zehnder optical modulator; a monitor configured to monitor a modulated light output from the optical modulator; a first controller configured to set a substrate bias voltage or an amplitude of a drive signal applied to the first waveguide of a waveguide pair of the optical modulator to a desired level that provides a first modulation index; and a second controller configured to control a substrate bias voltage or an amplitude of the drive signal applied to the second waveguide of the waveguide pair based upon an output signal from the monitor such that a second modulation index for the second waveguide becomes the same or closer to the first modulation index set for the first waveguide. | 02-25-2016 |
20160056896 | OPTICAL COMMUNICATION DEVICE AND METHOD OF CONTROLLING OPTICAL MODULATOR - An optical communication device includes an optical modulator of a Mach-Zehnder type, a low frequency superimposing circuit configured to superimpose a low frequency signal on a substrate bias voltage applied to the optical modulator, a monitor configured to monitor a modulated light output from the optical modulator, and a substrate bias controller configured to control the substrate bias voltage based upon a low frequency component contained in a monitor signal output from the monitor. | 02-25-2016 |
20150362823 | OPTICAL MODULE AND TRANSMITTING DEVICE - An optical module includes an optical modulator that modulates light by using an electrical signal input from a first surface to a plurality of electrodes; and a flexible substrate that has a plurality of wiring patterns electrically connected to the plurality of electrodes, respectively, on the first surface. The optical modulator has a bulging part that bulges out from the first surface opposed to the flexible substrate toward the flexible substrate and is in contact with the flexible substrate. | 12-17-2015 |
20150349911 | OPTICAL RECEIVER - An optical receiver includes a semiconductor optical amplifier configured to amplify an optical signal in which an optical signal with a first wavelength and an optical signal with a second wavelength are multiplexed. The receiver includes an optical demultiplexer configured to receive the optical signal amplified by the semiconductor optical amplifier and include a first filter configured to transmit the optical signal with the first wavelength with a transmission rate T | 12-03-2015 |
20150311976 | LIGHT SOURCE MODULE AND OPTICAL TRANSCEIVER - A light source module includes a single light source with two opposite light outputting faces, a first optical amplifier and a second optical amplifier provided on opposite sides of the light source adjacent to the corresponding light outputting faces, and a first monitor configured to monitor an output of the first optical amplifier, wherein a power output level of the first optical amplifier is controlled independently from the second optical amplifier based upon a monitoring result of the first monitor. | 10-29-2015 |
20150261063 | OPTICAL MODULE - An optical module includes a first substrate and a second substrate. The first substrate includes a first electrode and a first mark. The second substrate includes a second electrode and a second mark. The second substrate is formed so that at least part of the first mark is exposed in the vicinity of the second mark when the second electrode is electrically connected to the first electrode. | 09-17-2015 |
20150261062 | OPTICAL MODULE - An optical module includes: a substrate; a wiring pattern; and a cover material. The wiring pattern includes, on the substrate, an electrode portion having a predetermined width and a signal line having a width smaller than the predetermined width and connected to the electrode portion. The cover material covers a part of the electrode portion and the signal line. | 09-17-2015 |
20150261019 | OPTICAL MODULATOR - An optical modulator includes a substrate, an electrode, and an optical waveguide. The substrate includes a flat portion and a protruding portion protruded from the flat portion. The electrode is supported by the protruding portion. The optical waveguide is formed inside the protruding portion and waveguides light to be modulated with a voltage applied to the electrode. The protruding portion contains a part, present on the side of the electrode, of a light distribution region over which the light waveguided by the optical waveguide is distributed. A height of a tip of the protruding portion from the flat portion is smaller than a width of the light distribution region along a protruding direction of the protruding portion. A width of the tip of the protruding portion is smaller than a width of the light distribution region along a direction perpendicular to the protruding direction of the protruding portion. | 09-17-2015 |
20150261017 | OPTICAL TRANSMISSION DEVICE - A substrate is a substrate on which a first optical modulator and a second optical modulator are arranged in parallel along a width direction. A first prism moves, to a side opposite to the second optical modulator along the width direction of the substrate, an optical path of the first output light and the second output light that are obtained by light of the first wavelength being modulated by the first optical modulator. A second prism is arranged at a position away from the first prism along a longitudinal direction of the substrate and moves, to a side opposite to the first modulator along the width direction of the substrate, an optical path of the third output light and the fourth output light that are obtained by the light of the second wavelength being modulated by the second optical modulator. | 09-17-2015 |
20150253595 | OPTICAL MODULE AND OPTICAL MODULATION DEVICE - An optical module connected to an optical fiber for transmitting light includes: a substrate; a ferrule that is formed from a material capable of transmitting therethrough light having a predetermined wavelength, accommodates an end of the optical fiber, and is fixed on the substrate with a fixing agent cured by being irradiated with the light capable of passing through the material; and a semiconductor chip that is disposed on the substrate and modulates light emitted from the end of the optical fiber accommodated in the ferrule. | 09-10-2015 |
20150253593 | OPTICAL MODULE - An optical module includes: a substrate; a first terminal; a plurality of second terminals; a plurality of third terminals; and a plurality of wirings. The plurality of second terminals are on the substrate. The plurality of third terminals are disposed closer to an electrode than the plurality of second terminals on the substrate. The plurality of wirings extend from the plurality of second terminals through a side opposite to the first terminal and reach the electrode. | 09-10-2015 |
20150253592 | OPTICAL MODULE - An optical module includes a circuit substrate and a terminal. The circuit substrate includes a first pattern, a second pattern, a first cover material, and a second cover material. The first pattern electrically is connected to the terminal and formed in a predetermined shape on a first surface of the circuit substrate. The second pattern is formed in a predetermined shape at a position corresponding to the first pattern on a surface opposite to the first surface. The first cover material covers at least a portion of the first pattern to be bent along with bending of the circuit substrate. The second cover material covers at least an end of the second pattern. | 09-10-2015 |
20150253582 | POLARIZATION COMBINER AND OPTICAL MODULATION DEVICE - A polarization combiner includes: a base member that includes a body portion, an arm portion extending from the body portion, and a notch portion surrounded with the body portion and the arm portion; a polarization rotating element that is fixed to the arm portion of the base member and that rotates a polarization direction of a first polarized wave; and a polarization combining element that is fixed to the base member so as to face the notch portion of the base member and the polarization rotating element, the polarization combining element combining two polarized waves entering from a surface facing the notch portion and the polarization rotating element, the two polarized waves including the first polarized wave whose polarization direction is rotated by the polarization rotating element and a second polarized wave passing the notch portion. | 09-10-2015 |
20150253521 | OPTICAL TRANSMITTING APPARATUS - An optical transmitting apparatus includes: a substrate; optical modulators that are arranged in parallel to one another on the substrate and modulate light; waveguides that are formed on the substrate and guide signal light represented by at least one of modulated light beams obtained by the light being modulated by the plurality of optical modulators and monitor light represented by at least another one of the modulated light beams other than the signal light; lenses that collimate the signal light and the monitor light emitted from the waveguides; and a holding member that causes the signal light and the monitor light to be emitted from the lenses in mutually-different directions, by holding the lenses in such a manner that the optical axis of at least one of the lenses is out of alignment in a predetermined direction with the optical axis of at least one of the waveguides. | 09-10-2015 |
20150253506 | OPTICAL TRANSMITTER - A first lens transmits a beam of light having a vertical cross-sectional diameter made closer to a horizontal cross-sectional diameter. The beam of light is emitted from an optical waveguide on a substrate and configured such that the vertical cross-sectional diameter which is the diameter of a vertical cross section along the direction of the thickness of the substrate is greater than the horizontal cross-sectional diameter which is the diameter of a horizontal cross section along the direction of the width of the substrate. A second lens is disposed at a position, at which the vertical cross-sectional diameter and the horizontal cross-sectional diameter coincide with each other, so as to focus the beam of light on the optical fiber. The position is closer to the optical fiber than the first lens along the direction of travel of the beam of light transmitted by the first lens. | 09-10-2015 |
20150234252 | OPTICAL MODULATOR - An optical modulator includes a first coupler that branches an input light into two and outputs a first output light and a second output light; a first Mach-Zehnder interferometer (MZI) that modulates the intensity of the first output light from the first coupler and outputs a third output light; a second MZI that modulates the intensity of the second output light from the first coupler and outputs a fourth output light; a second coupler that combines the third output light from the first MZI and the fourth output light from the second MZI, branches a combined light into two, and outputs a fifth output light and a sixth output light. The interaction length of a branch of the first coupler and that of the second coupler are set such that the wavelength dependence of the splitting ratio of the first coupler is inversely related to that of the second coupler. | 08-20-2015 |
20150229411 | OPTICAL RECEPTION APPARATUS, AND CONTROL APPARATUS AND CONTROL METHOD OF OPTICAL RECEPTION APPARATUS - An optical reception apparatus may include a variable optical attenuator, a detector, and a controller. The variable optical attenuator may adjust a loss of an output optical power of a received light. The detector may detect that the output optical power is equal to or lower than a first level. The first level may be used to determine whether the output optical power is in a light interruption state. The controller may increase, in response to the detection made by the detector, the loss of the variable optical attenuator to a loss according to a second level. The second level may be used to determine whether the light interruption state is recovered. | 08-13-2015 |
20150188639 | OPTICAL TRANSMITTER AND CONTROL APPARATUS OF OPTICAL MODULATOR - An optical transmitter includes an optical modulator to modulate light output from a light source with a drive signal, a monitor to detect an average value and an alternating-current (AC) component of output light intensity of the optical modulator, and a controller to select one of a first bias control and a second bias control in accordance with an amplitude of the drive signal. The first bias control controls a bias voltage of the drive signal based on the average value, and the second bias control controls the bias voltage of the drive signal based on the AC component. | 07-02-2015 |
20150139667 | OPTICAL RECEIVER CIRCUIT - An optical receiver circuit includes a polarization beam splitter configured to split input signal light into two different polarized wave components; two variable optical attenuators configured to respectively adjust attenuation of and output the signal light split by the polarization beam splitter according to polarization state; and a single planar optical waveguide on which the polarization beam splitter and the two variable optical attenuators are disposed. | 05-21-2015 |
20150124313 | OPTICAL COMMUNICATION APPARATUS AND CONTROL METHOD OF OPTICAL COMMUNICATION APPARATUS - Provided are an optical amplifier, a light reception element, and a controller configured to decrease a gain of the optical amplifier according to an optical signal power input to the optical amplifier in response to a detection of a recovery of the optical signal input to the optical amplifier from an interruption of the optical signal and to increase the gain of the optical amplifier so that an input optical power to the light reception element approaches a target value after the decreasing of the gain. | 05-07-2015 |
20150117867 | OPTICAL MODULATOR AND OPTICAL TRANSMITTER - An optical modulator includes: a substrate that having an optical waveguide that includes a split section that splits light into two light waves, a pair of arms through which the light waves propagate, and a combining section that combines the light waves from the pair of arms with each other; and an electrode that overlaps part of the optical waveguide and generates an electric field by a voltage applied to the electrode. The optical waveguide has a narrow portion that is narrower than another portion of the optical waveguide and is arranged so that the electrode does not overlap with the narrow portion. | 04-30-2015 |
20150117865 | OPTICAL RECEIVING APPARATUS, OPTICAL TRANSMITTER AND RECEIVER MODULE, AND OPTICAL TRANSMITTING AND RECEIVING APPARATUS - A housing accommodates an optical waveguide substrate, plural signal light receiving elements, and a signal-light-level monitoring light receiving element. Signal light and locally oscillated light are input into optical waveguides in the optical waveguide substrate from a first end face of the optical waveguide substrate. The plural signal light receiving elements are disposed aligned on a side of a second end face opposite to a side of the first end face of the optical waveguide substrate. The signal-light-level monitoring light receiving element is disposed on a side of a third end face or a fourth end face between the first end face and the second end face of the optical waveguide substrate and at a position closer to the first end face than to the second end face. | 04-30-2015 |
20150117863 | OPTICAL RECEIVING DEVICE AND TRANSMISSION DEVICE - An optical receiving device includes: a conversion device that converts an input burst optical signal into a positive phase electrical signal and a negative phase electrical signal; an amplification device that amplifies the positive phase electrical signal and the negative phase electrical signal; a first output terminal that outputs the positive phase electrical signal; a second output terminal that outputs the negative electrical signal; a first transmission line that couples the amplification device with the first output terminal and transmits the positive phase electrical signal; a second transmission line that couples the amplification device with the second output terminal and transmits the negative phase electrical signal; and a control device that reduces a potential difference between the first transmission line and the second transmission line in a no-signal period that is provided between burst optical signals. | 04-30-2015 |
20150095871 | CIRCUIT DESIGN SUPPORT METHOD, COMPUTER PRODUCT, CIRCUIT DESIGN SUPPORT APPARATUS, AND SEMICONDUCTOR INTEGRATED CIRCUIT - A circuit design support method includes obtaining layout data that indicates positions of a plurality of clock receivers disposed in a circuit and positions of first clock wires disposed in the circuit; and calculating, by a computer, a value corresponding to lengths of wires respectively connecting the clock receivers to second clock wires on the basis of the obtained layout data, the value being calculated for each of a plurality of combinations of a count of the second clock wires and positions of the second clock wires, the second clock wires being disposed in a wiring layer of the circuit and being perpendicular to the first clock wires. | 04-02-2015 |
20150078763 | OPTICAL MODULE AND OPTICAL TRANSMITTER - An optical module includes a waveguide substrate including an optical waveguide and electrodes that apply electronic signals to the optical waveguide; a relay substrate disposed adjacent to the waveguide substrate; a terminal substrate disposed adjacent to the waveguide substrate and opposite to the relay substrate across the waveguide substrate; and a carrier substrate on which the waveguide substrate, the relay substrate, and the terminal substrate are mounted. The electrodes have a first interconnect unit from the relay substrate to the terminal substrate via the waveguide substrate and second interconnect units from the first interconnect unit and branching on the terminal substrate. Among the second interconnect units, a first interconnect branch includes a capacitor and a terminal resistor; and a second interconnect branch is connected to an interconnect of the carrier substrate via a bias resistor, passes under the waveguide substrate to a DC electrode for bias-adjusting on the relay substrate. | 03-19-2015 |
20150071582 | OPTICAL MODULATOR AND OPTICAL MODULATION CONTROL METHOD - An optical modulator includes: a modulator including an optical waveguide provided in a semiconductor substrate having an electro-optical effect and an electrode to apply an electric field depending on a bias voltage and a modulation signal to the optical waveguide; a driver circuit to generate a modulation signal in accordance with an input signal; a superimposer to superimpose a reference signal on the bias voltage, the reference signal having lower frequency than the modulation signal; and a controller to control a bias voltage in a direction orthogonal to a modulation direction of the modulator based on the frequency component of the reference signal extracted from a modulated optical signal generated by the modulator. | 03-12-2015 |
20150063809 | OPTICAL MODULE AND OPTICAL TRANSMITTER - An optical module includes a waveguide substrate having an optical waveguide and electrodes that apply electronic signals to the optical waveguide; a relay substrate disposed adjacently to the waveguide substrate; and a termination substrate disposed sandwiching the waveguide substrate with the relay substrate. The electrodes respectively have a first wiring portion connected from the relay substrate through the waveguide substrate to the termination substrate and a second wiring portion extending from the first wiring portion and branching on the termination substrate. In the second wiring portion, one branched wiring portion has a capacitor and a termination resistor, and another branched wiring portion extends through a bias resistor to a DC electrode on the relay substrate. The second wiring portion is divided into a first group extending in a first direction along the optical waveguide and a second group extending in a direction opposite to the first direction. | 03-05-2015 |
20150016771 | OPTICAL DEVICE AND FABRICATION METHOD OF OPTICAL DEVICE - An optical device includes a substrate having an electrooptical effect, and including an optical waveguide that guides light and a reflection groove having a bottom face that reflects light output from the optical waveguide; and a light-receiving element positioned above the reflection groove and fixed to the substrate. The light output from the optical waveguide into the reflection groove is reflected by the bottom face of the reflection groove while traveling through a space inside the reflection groove and is incident to the light-receiving element. | 01-15-2015 |
20140362874 | OPTICAL TRANSMITTER, OPTICAL RECEIVER AND OPTICAL TRANSCEIVER - An optical receiver includes: an optical receiving device configured to generate an analog received signal that represents a received modulated optical signal; an A/D converter configured to generate a digital received signal from the analog received signal; an E/O circuit configured to generate an optical digital signal from the digital received signal; an O/E circuit configured to generate an electric digital signal from the optical digital signal; and a digital signal processor configured to recover a data signal from the electric digital signal. | 12-11-2014 |
20140355924 | OPTICAL MODULATOR - An optical modulator includes: a substrate that has electrooptical effect and has a Mach-Zehnder modulator that has a 2×2 coupler acting as a splitter, two intermediate waveguides coupled to outputting waveguides of the splitter and another 2×2 coupler acting as a combiner coupled to the two intermediate waveguides; and a suppresser that suppresses a power of an output light from an uncoupled waveguide and an input light into the uncoupled waveguide of at least one of the 2×2 couplers in an extending direction of the Mach-Zehnder modulator. | 12-04-2014 |
20140348517 | OPTICAL RECEIVER - An optical receiver including a waveguide substrate including a first waveguide that transmits a main signal beam, a second waveguide that transmits a monitoring beam that has branched from the main signal beam, and a third waveguide that transmits an amplification beam to amplify the main signal beam; a light receiving device array including, integrally formed to the same substrate, a first light receiving device that detects the main signal beam and a second light receiving device that detects the monitoring beam; and a case that houses the waveguide substrate and the light receiving device array. The first light receiving device faces toward an end of the first waveguide, and the second light receiving device faces toward an end of the second waveguide. | 11-27-2014 |
20140348500 | OPTICAL RECEIVER AND SLICE LEVEL CONTROL METHOD - An optical receiver includes a first discriminator in which an optimal point of a slice level is set and that compares a received signal to the slice level and discriminately outputs the received signal; a second discriminator that is connected in parallel to the first discriminator, compares the received signal to a slice level, and discriminately outputs the received signal; and a computing device that variably controls the slice level of the first and the second discriminators, respectively. The computing device executes a first process of setting the slice level of the first discriminator to be a predetermined slice level, calculating a pseudo error rate obtained when the slice level of the second discriminator is caused to variably scan, and setting the slice level of the first discriminator within a range in which the error rate does not vary. | 11-27-2014 |
20140341240 | METHOD OF CONTROLLING TEMPERATURE OF SEMICONDUCTOR LASER, TEMPERATURE CONTROL DEVICE OF SEMICONDUCTOR LASER AND NON-TRANSITORY COMPUTER-READABLE MEDIUM - A method of controlling a temperature of a semiconductor laser includes: controlling a supply current so that a temperature of a temperature control element is changed to a target temperature, the temperature control element controlling a temperature of the semiconductor laser by a temperature changing according to the supply current supplied to the temperature control element; and performing a control for maintaining a calculated value calculated by a digital filter at a threshold when it is detected that the calculated value reaches the threshold, the calculated value being the supply current for achieving the target temperature, the threshold being equal to or less than an output limit of the digital filter. | 11-20-2014 |
20140334831 | OPTICAL RECEIVER AND LIGHT RECEIVING METHOD - An optical receiver receives coherent light. The optical receiver includes an amplitude adjuster, a signal processor, and a controller. The amplitude adjuster adjusts amplitude of an input signal to output an analog signal. The signal processor receives a digital signal generated from the analog signal output from the amplitude adjuster, extracts clock components from the digital signal, and after establishing synchronization between the clock components and data components, extracts the data components from the digital signal to process the data components. The controller sets amplitude of the analog signal to first amplitude before establishment of synchronization by the digital signal, and changes the set amplitude to second amplitude that is smaller than the first amplitude after the establishment of synchronization. | 11-13-2014 |
20140328588 | OPTICAL COMMUNICATION SYSTEM, OPTICAL TRANSMITTER, AND OPTICAL RECEIVER - An optical communication system includes an optical transmitter, and an optical receiver connected via a transmission line to the optical transmitter, in which system the optical transmitter transmits a continuous-wave light signal that enables beat detection when combined with a local oscillator signal in the optical receiver, and the optical receiver acquires a beat waveform through digital sampling by detecting the light signal using the local oscillator signal, performs frequency analysis on digitally sampled data having the beat waveform prior to demodulation, and controls the local oscillator frequency based upon the beat frequency. | 11-06-2014 |
20140294380 | OPTICAL DEVICE AND TRANSMITTER - An optical device includes an optical waveguide that includes an incident waveguide, parallel waveguides along an electrode, and emission waveguides, formed on a substrate having an electro-optical effect, a first emission waveguide among the emission waveguides is set as an output waveguide of signal light, for output to an external destination and a second emission waveguide among the emission waveguides is set as a monitoring optical waveguide for the signal light; a photodetector that is disposed over the monitoring optical waveguide; and a groove formed on a portion of the substrate, where the photodetector of the monitoring optical waveguide is disposed. The monitoring optical waveguide has a width that, as compared with the width at a starting point side, is formed to increase as the monitoring optical waveguide approaches the groove. | 10-02-2014 |
20140286614 | OPTICAL MODULE - An optical module includes: a flexible board having a first surface on which a component is mounted and a second surface opposite to the first surface; a bottom electrode part having a bottom surface on which a heat release electrode is provided, the bottom electrode part mounted on the first surface of the flexible board; and a heat release member configured to absorb heat from the bottom electrode part and release the heat to outside. The heat release member is arranged close to said second surface of the flexible board at a position where the bottom electrode part is mounted. | 09-25-2014 |
20140161408 | OPTICAL MODULE - An optical module includes a wiring board on which a first opening and a second opening are provided having, between the first and second openings, a traversing portion on which a signal wire is arranged, an optical component that is mounted on a first plane side of the first opening and the second opening of the wiring board and that generates heat, a heat sink arranged on a second plane side, which is on a reverse of the first plane side, of the first opening and the second opening of the wiring board, and an anisotropic heat dissipation sheet that is provided between the traversing portion and the heat sink, and the optical component, and that has a thermal conductivity higher in second directions, which cross the traversing portion in a plane orthogonal to first directions, than in the first directions, which are thickness directions of the wiring board. | 06-12-2014 |
20140153934 | OPTICAL MODULATOR AND OPTICAL TRANSMITTER - An optical modulator includes a Mach-Zehnder optical waveguide that includes a pair of parallel waveguides, and a two-input-one-output optical coupler that couples light output from the parallel waveguides; a branching waveguide that branches a portion of light output from the optical coupler; and a light receiving unit that receives the light output from the branching waveguide. Orientation of an output end of the branching waveguide is angled toward the light receiving unit, to be oblique with respect to the parallel waveguides, and orientation of an output end of the optical coupler is angled toward a side opposite to that of the output end of the branching waveguide, to be oblique with respect to the parallel waveguides. | 06-05-2014 |
20140126913 | MODULATING APPARATUS - A modulating apparatus includes a branch that branches input light; a first modulating unit that modulates the phase of a first branch obtained by the branch; a second modulating unit that modulates a second branch obtained by the branch; a third modulating unit that is connected in series to the first modulating unit, transmits the first branch without branching the first branch, modulates the phase of light transmitted by controlling a refractive index of the light transmitted; a fourth modulating unit that is connected in series to the second modulating unit, transmits the second branch without branching the second branch, and modulates the phase of a light transmitted by controlling a refractive index of the light transmitted; and a coupler that couples the first branch modulated by the first and the third modulating units and the second branch modulated by the second and the fourth modulating units, at different intensities. | 05-08-2014 |
20140119686 | OPTICAL MODULATOR AND OPTICAL TRANSMITTER - An optical modulator includes a package | 05-01-2014 |
20140078508 | OPTICAL MODULE - An optical module includes an interferometer having at least two optical exit ends; an optoelectronic converting element having at least two light-receiving surfaces; and plural lenses that are disposed between the interferometer and the optoelectronic converting element, that optically couple light exiting from the interferometer with two light-receiving surfaces of the optoelectronic converting element. The lenses are disposed having focal distances and a distance therebetween that reduce positional displacement on the two light-receiving surfaces of the optoelectronic converting element, the positional displacement being generated at each of the two optical exit ends of the interferometer. | 03-20-2014 |
20140072313 | OPTICAL TRANSMISSION APPARATUS - A first clock modulator branches a light beam, varies a phase difference of the resulting light beams according to a first clock, and causes interference of the light beams. A second clock modulator branches a light beam from the first clock modulator and synchronized with the first clock, varies a phase difference of the resulting light beams according to a second clock, and causes interference of the light beams. A third clock modulator branches a light beam from the first clock modulator and inversely synchronized with the first clock, varies a phase difference of the resulting light beams according to a third clock, and causes interference of the light beams. The second clock and the first clock have identical cycles and differing phases. The third clock and the second clock have phases that differ by a 1/2 cycle. Four data modulators modulate the light beams from the clock modulators. | 03-13-2014 |
20140029958 | DETECTING APPARATUS, OPTICAL RECEIVING APPARATUS, DETECTING METHOD, AND OPTICAL RECEIVING METHOD - A detecting apparatus includes a threshold detection circuit that detects by a switchable time constant, a threshold of a level of an input optical burst signal; an input detection circuit that detects input of the optical burst signal; a level detection circuit that detects a level of the optical burst signal; a switching circuit that switches the time constant when a period that corresponds to the level detected by the level detection circuit has elapsed after the input is detected by the input detection circuit; and an output circuit that outputs the threshold detected by the threshold detection circuit. | 01-30-2014 |
20140029895 | OPTICAL MODULE - An optical module includes a rotating bail disposed on a front part of a case that is inserted into and removed from a cage; a slide plate that slides along a longitudinal direction of the case in conjunction with rotation of the bail; and an engagement member is disposed on the slide plate, freely engages with an engagement member of the cage, and is released from an engaged state by a sliding of the slide plate in conjunction with the rotation of the bail. The bail and the slide plate are formed by an integrated metal plate in a folded state. | 01-30-2014 |
20130251303 | OPTICAL DEVICE HAVING OPTICAL MODULATORS - An optical device includes first and second optical modulators formed on a substrate having electro-optical effect. The first optical modulator includes a first optical waveguide; a first signal electrode configured to provide a first data signal for the first optical waveguide; and a first DC electrode, arranged at an output side of the first signal electrode, and configured to provide first DC voltage for the first optical waveguide. The second optical modulator includes a second optical waveguide; a second signal electrode configured to provide a second data signal for the second optical waveguide; and a second DC electrode provided, arranged at an input side of the second signal electrode, and configured to provide second DC voltage for the second optical waveguide. Input portions of the first and second signal electrodes are arranged at a same side edge of the substrate. | 09-26-2013 |
20130243363 | OPTICAL MODULATOR - An optical modulator includes a first coupler that branches an input light into two and outputs a first output light and a second output light; a first Mach-Zehnder interferometer (MZI) that modulates the intensity of the first output light from the first coupler and outputs a third output light; a second MZI that modulates the intensity of the second output light from the first coupler and outputs a fourth output light; a second coupler that combines the third output light from the first MZI and the fourth output light from the second MZI, branches a combined light into two, and outputs a fifth output light and a sixth output light. The interaction length of a branch of the first coupler and that of the second coupler are set such that the wavelength dependence of the splitting ratio of the first coupler is inversely related to that of the second coupler. | 09-19-2013 |
20130223838 | TRANSMITTING APPARATUS AND TRANSMITTING METHOD - A transmitting apparatus connected via an optical branching apparatus to an optical communication device group includes a control unit that for each periodic transmission period including a first transmission period with a test period in which the optical communication device group is not allowed to transmit optical signals and a second transmission period without the test period, allows the optical communication device group to transmit the optical signals during a period different from the test period; a test light sending unit that sends test light to the optical branching apparatus during the test period; a light receiving unit that receives optical signals transmitted from the optical communication device group, and reflected light of the sent test light; a measuring unit that measures intensity of the reflected light received at different elapsed times after the test light is sent; and an output unit that outputs information based on the measured intensity. | 08-29-2013 |
20130194657 | OPTICAL AMPLIFIER AND MANUFACTURING METHOD OF OPTICAL AMPLIFIER - An optical amplifier includes multiple semiconductor optical amplifiers (SOAs) provided on a semiconductor substrate and having different wavelength bands to be amplified; multiple branching paths that branch an input optical signal and input the branched optical signals into the parallel SOAs, respectively; and multiple combining paths that combine and output the optical signals after amplification by the SOAs. | 08-01-2013 |
20130156444 | OPTICAL MODULATION DEVICE AND CONTROL METHOD IN OPTICAL MODULATION DEVICE - In an optical modulation device, a driver applies a drive signal based on a data signal to a modulation unit, the modulation unit modulates the light input from an LD by the drive signal, and a bias control unit calculates a bias voltage value so as to make the f0 element closer to “0,” according to a detection result in a synchronization detection unit, and supplies a bias voltage of the calculated voltage value to the modulation unit. The bias control unit stops ABC control when the data signal is in a state different from a predefined state during the ABC control, and, after the stop of the ABC control, restarts the ABC control using, as an initial value, a bias voltage value calculated before the stop of the ABC control. | 06-20-2013 |
20130156441 | OPTICAL TRANSCEIVER AND PRODUCTION METHOD THEREOF - An optical transceiver includes a single-fiber bidirectional optical transmission/reception device, a circuit board, a transmission-side FPC, a reception-side FPC and a separation wall. The optical transceiver includes a single-fiber bidirectional optical transmission/reception device includes an LD stem that converts an electric signal into an optical signal and transmits it, and a PD stem that receives the optical signal and converts it into an electric signal. The transmission-side FPC electrically connects the LD stem and the circuit board. The reception-side FPC electrically connects the PD stem and the circuit board. The separation wall is formed between the transmission-side FPC and the reception-side FPC, and grounded to the chassis of the optical transceiver. The reception-side FPC is folded and set between the chassis and the separation wall such that the board front surface is an inner side, where the micro-strip line is formed on the above board front surface. | 06-20-2013 |
20130155482 | OPTICAL MODULATION DEVICE AND OPTICAL MODULATION METHOD - In an optical modulation device, a first drive signal and a first bias signal are applied to a phase modulation unit, a second drive signal and a second bias signal are applied to a phase modulation unit, and a third bias signal is applied to a π/2 phase shift unit. A control unit adjusts the third bias signal in a first adjustment period, adjusts the first drive signal and the first bias signal in a second adjustment period next to the first adjustment period, and adjusts the second drive signal and the second bias signal in a third adjustment period next to the second adjustment period. The control unit starts the second adjustment period before a gap between the current value of an adjustment reference signal and a target value is filled, and starts the third adjustment period before a gap in the second adjustment period is filled. | 06-20-2013 |
20130148981 | OPTICAL TRANSMITTER - After a startup of an optical transmitter, a control is started in such a way that a modulation amplitude of a driving signal of a phase modulator is set as 0, and that an operational point of a bias voltage is set as the lowest point of light transmission characteristics of the phase modulator. When the operational point of the bias voltage reaches the lowest point, the modulation amplitude of the driving signal is gradually increased from 0 to 2Vπ. | 06-13-2013 |
20130142472 | OPTICAL TRANSMITTER AND OPTICAL TRANSMISSION METHOD - An optical transmitter includes a first Mach-Zehnder, second Mach-Zehnders, a plurality of electrodes and a shift circuit. The first Mach-Zehnder is formed in an LN substrate. The second Mach-Zehnders are formed in branch waveguides of the first Mach-Zehnder. The plurality of electrodes are set in the second Mach-Zehnders and modulate lights input in the second Mach-Zehnders using an electric potential of the electrodes. The shift circuit causes a phase difference between the lights modulated in the above plurality of electrodes and output from the second Mach-Zehnders. The Mach-Zehnder synthesizes the above lights of different phases and generates an output signal. | 06-06-2013 |
20130101296 | OPTICAL TRANSMITTER, OPTICAL TRANSMISSION METHOD, AND OPTICAL TRANSMISSION/RECEPTION SYSTEM - An optical transmitter includes: a selection circuit; a signal processing circuit; an optical modulator; and a control circuit. The selection circuit selects signal components on the sides of the maximum and minimum values in a multivalued electrical signal for modulation of a transmitting signal. The signal processing circuit generates a multivalued electrical signal into which the transmitting signal is converted by a combination of a superimposed signal that a low-frequency wave is superimposed on the signal components and a signal having a plurality of intermediate amplitude values on which the low-frequency wave is not superimposed. The optical modulator modulates a carrier light on the basis of the multivalued electrical signal. The control circuit controls the reference amplitude value or amplitude of the multivalued electrical signal on the basis of the low-frequency components contained in a modulated optical signal. | 04-25-2013 |
20130084065 | OPTICAL TRANSMITTER AND WAVEFORM COMPENSATION METHOD - 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. | 04-04-2013 |
20130039612 | OPTICAL MODULATOR - An optical modulator comprises a substrate having an electro-optical effect, an optical waveguide formed in the substrate, a buffer layer provided above the optical waveguide, a semiconductor film provided above the buffer layer and having an aperture at a top of the optical waveguide, and an electrode provided above the buffer layer and electrically coupled to the semiconductor film. | 02-14-2013 |
20130027762 | CIRCUIT BOARD AND OPTICAL MODULATOR - A printed circuit board (PCB) has a connection ground pattern and a wiring ground pattern. The connection ground pattern is a pattern for soldered connection formed on a first wiring layer. The wiring ground pattern is formed to be spaced from the connection ground pattern on the first wiring layer. The connection ground pattern and the wiring ground pattern are electrically coupled via a second wiring layer. When the wiring ground pattern is covered with an insulating layer, such as a solder resist, even if the position of an end of the insulating layer varies among wiring ground patterns, an influence on an exposed area of the connection ground pattern is eliminated. | 01-31-2013 |
20130010350 | PLC-TYPE DELAY DEMODULATION CIRCUIT AND PLC-TYPE OPTICAL INTERFEROMETER - Disclosed are a PLC-type delay demodulation circuit and a PLC-type optical interferometer capable of reducing the size of a PLC chip with respect to the arrangement of various kinds of light output waveguides. In a PLC-type delay demodulation circuit, arm waveguides of a first MZI and arm waveguides of a second MZI are formed so as to overlap each other in the same region of a planar lightwave circuit. The optical paths of the MZIs are arranged such that the propagation directions of two DQPSK signals branched by a Y-branch waveguide are opposite to each other. | 01-10-2013 |
20120269508 | OPTICAL TRANSMITTER AND OPTICAL TRANSMISSION APPARATUS - An optical transmitter includes a laser configured to emit light, a power of the light increasing with temperature decreasing, a Faraday rotator configured to rotate a polarization direction of the light in accordance with the temperature, and a first polarizer that has a principal axis inclined at a given angle and inputs the light output from the Faraday rotator. | 10-25-2012 |
20120251128 | OPTICAL TRANSMITTER AND METHOD FOR OPTICAL SIGNAL WAVEFORM COMPENSATION - 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. | 10-04-2012 |
20120155880 | OPTICAL MODULATOR AND OPTICAL MODULATION CONTROL METHOD - An optical modulator includes: a modulator including an optical waveguide provided in a semiconductor substrate having an electro-optical effect and an electrode to apply an electric field depending on a bias voltage and a modulation signal to the optical waveguide; a driver circuit to generate a modulation signal in accordance with an input signal; a superimposer to superimpose a reference signal on the bias voltage, the reference signal having lower frequency than the modulation signal; and a controller to control a bias voltage in a direction orthogonal to a modulation direction of the modulator based on the frequency component of the reference signal extracted from a modulated optical signal generated by the modulator. | 06-21-2012 |
20120128289 | OPTICAL MODULATOR AND OPTICAL MODULATION CONTROL METHOD - An optical modulator includes: a modulator including an optical waveguide provided in a semiconductor substrate having an electro-optical effect and an electrode for applying an electric field depending on a bias voltage and a modulation signal to the optical waveguide; a modulation signal generator to generate the modulation signal of a first frequency; a superimposer to superimpose a signal of a second frequency different from the first frequency on the bias voltage; and a bias controller to control the bias voltage in a modulation direction of the modulator and the bias voltage in an orthogonal direction which is orthogonal to the modulation direction based on a phase of the second frequency component extracted from a modulated optical signal generated by the modulator. | 05-24-2012 |
20120121259 | OPTICAL TRANSMISSION DEVICE AND OPTICAL TRANSMISSION METHOD - An optical transmission device includes a first power monitor to monitor a first signal into which second signals with respectively different wavelengths are multiplexed so as to measure received power of the first signal; an amplifier to amplify the first signal, to generate a third signal; a driver to drive the amplifier; a demultiplexer to separate the third signal into fourth signals with the different respectively wavelengths; second power monitors each to monitor each of the fourth signals so as to measure received power of each of the fourth signals; a memory to store therein data related to gain in the amplifier, the data corresponding to each of wavelengths of the second signals, with respect to parameters which are the received power measured by the first power monitor and driving condition; and a processor to calculate power of each of the second signals. | 05-17-2012 |
20120120619 | COMMUNICATION DEVICE AND METHOD OF COUPLING ELECTRICALLY CIRCUIT BOARDS - There is provided a communication device that includes a first circuit board which includes a first ground pattern (GND) and a first signal line formed on a substrate, a ground pin electrically coupled with the first GND, where the ground pin protrudes from an end of the substrate, and a signal pin formed in the substrate and electrically coupled with the first signal line, where the signal pin protrudes from the end. The communication device further includes a send circuit board which includes a second GND and a second signal line, wherein when an end of the circuit board is inserted into a space between the ground pin and the signal pin, the first signal line and the second signal line are electrically coupled with each other via the signal pin and the first GND and the second GND are electrically coupled with each other via the ground pin. | 05-17-2012 |
20120114340 | OPTICAL TRANSMITTER AND INTERCONNECTING CIRCUIT BOARD - An optical transmitter including: an optical module; an interconnecting circuit board configured to be electrically coupled to the optical module; and a printed circuit board configured to be electrically coupled to the interconnecting circuit board; wherein the interconnecting circuit board includes: a coplanar waveguide; and a microstrip line including a signal wiring line extended from an end of the coplanar waveguide and a ground wiring line, wherein the width of the signal wiring line is narrower than the width of a signal wiring line of the coplanar waveguide, and the spacing between the signal wiring line extended from the end of the coplanar waveguide and the ground wiring line is smaller than the spacing between the signal wiring line of the coplanar waveguide and the ground wiring line. | 05-10-2012 |
20120113596 | ELECTRONIC APPARATUS, METHOD FOR MOUNTING A DEVICE, AND OPTICAL COMMUNICATION APPARATUS - An electronic apparatus includes a substrate, a device including a flange, the device being mounted at a first side of the substrate, a plate arranged at a position corresponding to the device at a second side of the substrate, the second side being opposite to the first side, and a securing member that secures the device to the substrate. | 05-10-2012 |
20120106979 | OPTICAL TRANSMITTER AND OPTICAL TRANSMISSION APPARATUS - An optical transmitter is disclosed. An optical modulator outputs an optical signal by modulating light being input, and has an optical absorption characteristic which changes a degree of optical absorption depending on a bias voltage being applied and includes a first characteristic region and a second characteristic region in which the degree of the optical absorption is greater than the first characteristic region. An power source applies an electric field generated by applying a predetermined shutdown bias voltage corresponding to the second characteristic region to electrodes provided in two interference optical guides formed in the optical modulator, when an output of the optical signal from the optical modulator is shut down to be less than or equal to a desired amount. | 05-03-2012 |
20120087652 | OPTICAL COMMUNICATION DEVICE AND POWER-SAVING CONTROL METHOD OF OPTICAL COMMUNICATION DEVICE - A power-saving mode flag generating unit | 04-12-2012 |
20120087617 | OPTICAL MODULATOR AND OPTICAL MODULATING METHOD - An optical modulator includes a modulator that modulates an input light of light by using an input signal. The optical modulator further includes a compensation circuit that compensates the phase of a signal light in accordance with an input current, the signal light being the input light modulated by the modulator. The optical modulator further includes a detector that detects the difference between the phase of the signal light compensated by the compensation circuit and the phase of an input signal that is input to the modulator. The optical modulator further includes an adjustment circuit that adjusts, in accordance with the phase difference detected by the detector, the input current that is input to the compensation circuit. | 04-12-2012 |
20120082467 | OPTICAL TRANSMITTER, OPTICAL TRANSMISSION DEVICE, AND METHOD OF CONTROLLING OPTICAL TRANSMITTER - An optical transmitter includes a driver outputting data; an optical modulator outputting an optical modulation signal by modulating light from a light source based on the data output from the driver; a detector detecting at least one of a signal intensity of the optical modulation signal from the optical modulator and a signal intensity of the data from the driver and outputs a detection result; and an adjustor adjusting a signal parameter of the data based on the detection result. | 04-05-2012 |
20120074992 | CIRCUIT MODULE - A circuit module includes: control object circuits which start operations when a power supply voltage reaches a target value; a current sink circuit which consumes a current supplied thereto; and a power supply activation control unit which increases the current flowing into the current sink circuit at a predetermined rate before starting the operations of the control object circuits and which starts the operations of the control object circuits and simultaneously blocks the supply of the current to the current sink circuit in a case where an amount of the current flowing into the current sink circuit is equivalent to an amount of current to be increased by starting the operations of the control object circuits when the power supply voltage reaches the target value. | 03-29-2012 |
20120069542 | Communication module - A communication module includes a communication circuit, a connector coupled to the communication circuit, a housing having a space for arranging the communication circuit and an aperture for arranging the connector, and a projection provided at facing inside wall surface of the housing and attenuating an electromagnetic wave within a frequency range transmitted in the space. | 03-22-2012 |
20120020658 | Optical device - An optical device includes a light source, a controller that supplies control information to the light source and controls an output level of the light source, a monitor that outputs an operation state of the optical output as a monitor output, and an auxiliary controller that records the monitor output and the control information. When the controller stops supplying the control information, the auxiliary controller outputs the control information to the light source in accordance with the relation between the recorded monitor output and the recorded control information. | 01-26-2012 |
20120008303 | Communication module - An electromagnetic wave suppression material is fixed to a case of a communication module. The electromagnetic wave suppression material suppresses radiation of electromagnetic waves by coming into contact with a cage that is a module insertion portion of a chassis when the communication module is inserted into the cage. A piezoelectric element is provided on the case, and located between the case and the electromagnetic wave suppression material. When the communication module is inserted into the cage, the controller applies a voltage to the piezoelectric element to stretch it by the applied voltage, thereby increasing contact pressure between the cage and the electromagnetic wave suppression material. | 01-12-2012 |
20110305412 | OPTICAL WAVEGUIDE, OPTICAL MODULATOR AND OPTICAL COUPLER - An optical waveguide formed in a substrate including: a curved waveguide; and a splitter that is coupled to the curved waveguide and branches, wherein a low refraction index portion having an effective refraction index that is lower than that of a start point of the curved waveguide on an opposite side of the splitter is provided in a waveguide extending from the start point of the curved waveguide to the splitter. | 12-15-2011 |
20110299559 | OPTICAL DEVICE - When environmental temperature becomes low, the quantity of light of the backward output light irradiated onto a light absorber formed on a mount over which a chip is mounted, is increased by a light quantity adjuster, to increase the optical absorption by the light absorber, thereby raising its temperature. As a result, the temperature of the chip on the mount rises, thereby enabling to substantially narrow a temperature range on a low temperature side. Accordingly, an optical device with low power consumption that can satisfy characteristics required for signal transmission at a required rate over a wide temperature range can be provided. | 12-08-2011 |
20110262149 | LIGHT RECEPTION DEVICE AND METHOD FOR CONTROLLING THE SAME - A light reception device includes: an interferometer that outputs a signal obtained by making an optical phase modulated signal interfere with a reference signal after shifting an optical phase of the optical phase modulated signal by a given amount; a light reception element that receives an output signal from the interferometer and converts the output signal into a light reception current; and a phase controller that controls a control amount in controlling the given amount so that a value of a function, which is calculated based on an amount relating to the light reception current and a change amount of an amount relating to the light reception current against the control amount, becomes an extreme value or 0. | 10-27-2011 |
20110243572 | OPTICAL RECEIVER AND COMMUNICATION SYSTEM - There is provided an optical receiver including a variable-ratio splitter to split an input signal light into a plurality of signal lights, based on a variable ratio, a plurality of photo detectors to receive the plurality of signal lights respectively, an operation circuit to output a reception electrical signal, based on a reception processing on one of the plurality of signal lights, a calculation circuit to calculate a total power of the plurality of signal lights received by the plurality of photo detectors, and an output unit to output a signal regarding the total power. | 10-06-2011 |
20110217048 | Delayed interferometer and optical receiver - A delayed interferometer includes a branching unit that branches an optical signal into a first optical signal and a second optical signal; a guiding unit that guides the first optical signal in a first optical path to delay the first optical signal when a polarization direction of the first optical signal is the first direction, and guides the first optical signal in a second optical path when the polarization direction of the first optical signal is the second direction perpendicular to the first direction; a demodulating unit that causes the first optical signal guided in the first optical path or the second optical path and the second optical signal branched by the branching unit to interfere with each other, thereby demodulating the optical signal; and a polarization direction adjusting unit to adjust the polarization direction of the first optical signal in the first direction or the second direction. | 09-08-2011 |
20110204215 | OPTICAL DEVICE AND METHOD OF MANUFACTURING THE SAME - 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. | 08-25-2011 |
20110194802 | MACH-ZEHNDER MODULATOR - A mach-zehnder optical modulator includes a substrate having electrooptical effect, wherein: the substrate has an inputting waveguide portion, two intermediate waveguide portions, an outputting waveguide portion and a sub optical waveguide portion, the inputting waveguide portion being branched and coupled to the two intermediate waveguide portions, the two intermediate waveguide portions being combined and coupled to the outputting waveguide portion, the sub optical waveguide being provided on at least one side of the outputting optical waveguide portion and having a given distance from the outputting optical waveguide portion, the sub optical waveguide portion guiding an off-light emitted from a combining portion of the two intermediate waveguide portions; and a width of a starting point of the sub optical waveguide portion is larger than the outputting waveguide portion. | 08-11-2011 |
20110188799 | OPTICAL DEVICE AND OPTICAL TRANSMITTER - An optical device includes a substrate having an electro-optical effect; a main waveguide provided on the substrate; a first Mach-Zehnder part having first waveguides provided on the substrate and coupled with the main waveguide, and first DC electrodes provided between the first waveguides and on the first waveguides and used to generate DC electric fields in the first waveguides; and second Mach-Zehnder parts respectively associated with the first waveguides and comprising second waveguides coupled with each of the first waveguides and second DC electrodes used to generate DC electric fields in the second waveguides, at least one of the second Mach-Zehnder parts being configured to have no second DC electrode provided between the second waveguides and have the second DC electrodes on the second waveguides. | 08-04-2011 |
20110186954 | PHOTORECEIVING DEVICE - The wiring arrangement length in a photoreceiving device is shortened. The photoreceiving device includes an amplifier for amplifying an output of the photoreceiving element and a photoreceiving element and they are mounted at a base member. A plurality of first bonding pads and a plurality of second bonding pads for connection to power supply are provided at both sides of a transmission path of an input or output signal of a photoreceiving element. Furthermore, at a position other than the parts arrangement surface of the base member, a plurality of first bonding pads are electrically connected to a plurality of second bonding pads. | 08-04-2011 |
20110182591 | OPTICAL RECEIVER - An optical receiver includes: an optical amplifier amplifying an optical signal fed thereinto according to an operating current fed thereinto, the optical signal being a wavelength-multiplexed optical signal, a demultiplexer demultiplexing an optical signal output from the optical amplifier; and an operating-current control circuit selecting a monitoring target from a plurality of wavelength signals output from the demultiplexer and controlling the operating current of the optical amplifier so that optical power of the monitoring target is controlled to be a predetermined value. | 07-28-2011 |
20110170874 | Method, system, and apparatus for optical communication - An optical communication method includes outputting an optical data signal in which a signal amplitude of a non-data area that is an area other than a data area is made higher than a signal amplitude of the data area, to a predetermined receiver, receiving an optical input including the optical data signal with the predetermined receiver, detecting each of the signal amplitude of the non-data area and the signal amplitude of the data area of the optical input, creating a threshold for encoding the data area based on the signal amplitude of the data area, determining whether the optical data signal is received, based on the signal amplitude of the non-data area, and outputting a data signal in which the data area is encoded by using the threshold of the optical data signal, when it is determined that the optical data signal is received. | 07-14-2011 |
20110170863 | PHASE MODULATED SIGNAL RECEIVER - A phase modulated signal receiver includes an operation part and a control part. An input power of a received light signal is measured based on current monitored by a monitor circuit. The operation part is configured to correct, on the basis of a ratio of the input power measured when a delay of a phase reference light output from a delay interferometer is a first delay and the input power when the delay of the phase reference light is a second delay, a value of the current monitored by the monitor circuit when the delay is the first delay to a corrected value that depends on the input power of the received light signal obtained when the delay is the first delay. The control part is configured to control the delay of the phase reference light of the delay interferometer by comparing the current monitored when the delay is the first delay and the corrected value of the current monitored when the delay is the second delay and maximizing or minimizing the current monitored by the monitor circuit. | 07-14-2011 |
20110170856 | Optical transmission device - An optical transmission device includes a first optical output unit including a chip and outputting an optical signal having a predetermined wavelength according to a temperature, a second optical output unit including a chip of which a temperature is controlled independently of the chip of the first optical output unit and outputting an optical signal having a predetermined wavelength according to a temperature, a failure detecting unit detecting a failure of the chip in operation of the first optical output unit, a switching unit switching its operation to the chip of the second optical output unit whose output optical signal has a same wavelength as that of the optical signal of the chip in operation of the first optical output unit when the failure detecting unit detects the failure, and a transmitting unit transmitting the optical signal output from the chip of the second optical output unit. | 07-14-2011 |
20110158643 | Optical transmission module and wavelength control method of optical transmission module - An optical transmission module includes a variable wavelength light source; an alternating current adding unit that adds an alternating current to a drive current to the variable wavelength light source; a first detector to detect optical power of an output light; a filter to input the output light from the variable wavelength light source in which transmission wavelength periodically increases and decreases; a second detector to detect optical power of transmitted light transmitted through the filter; an extraction unit to extract a wavelength fluctuation component of the output light based on the optical power of the output light and the optical power of the transmitted light; a phase comparison unit to compare a phase of the wavelength fluctuation component with a phase of the alternating current; and a wavelength controller to control a wavelength of the output light by controlling a temperature of the variable wavelength light source. | 06-30-2011 |
20110158640 | Chirp measuring device and chirp measurement method - A chirp measuring device includes a chirp measuring unit that measures chirps indicating a time variation of an optical frequency of input light signal; a signal averaging unit that computes, based on a predetermined number of additions for signal averaging, an average of the chirps measured by the chirp measuring unit; a chirp threshold value determining unit that determines whether the average computed by the signal averaging unit is not less than a predetermined chirp threshold value; and a determination result output unit that outputs a determination result obtained by the chirp threshold value determining unit. | 06-30-2011 |
20110096338 | Delay interferometer using magneto-optic effect - A delay interferometer includes first and second optical paths into which incident signal light is split, a first converter including one or more conversion parts to convert the signal light on the first optical path into circularly polarized light and to convert the circularly polarized light into linearly polarized signal light, a phase adjuster to shift an optical phase of the circularly polarized light through a magneto-optic effect, and a second converter to convert a polarization state of the signal light on the second optical path into substantially the same polarization state as a polarization state of the linearly polarized signal light. | 04-28-2011 |
20110081107 | OPTICAL MODULATOR AND OPTICAL TRANSMITTER - An optical modulator including: a substrate which has electro-optic effect; a Mach-Zehnder optical interferometer which is formed in the substrate and which includes a first waveguide and a second waveguide; a signal electrode which applies an electrical field to the Mach-Zehnder optical interferometer through being supplied with an electric signal corresponding to a signal for optical modulation; a ground electrode formed apart from the signal electrode; and a conductor section which is narrow in a middle thereof along the light propagating direction and which gradually becomes wider towards the starting end and the terminating ends thereof along the light propagating direction in an interacting portion at which the electric field applied by the signal electrode interacts with light propagating through the first waveguide and the second waveguide. | 04-07-2011 |
20110064417 | COMMUNICATION SYSTEM - In a communication system, a signal processor of a communication apparatus transmits, when causing a communication module to perform a predetermined operation, a control signal at a predetermined level. Further, when authenticating the communication module, the signal processor changes a level of the control signal into a previously set authentication pattern and transmits the control signal. An operation controller of the communication module receives the control signal transmitted from the signal processor. When a level of the received control signal is a predetermined level, the operation controller performs a predetermined operation corresponding to the predetermined level. Further, when a level of the received control signal is an authentication pattern, the operation controller performs authentication control by matching or comparing the authentication pattern with a previously recognized pattern. | 03-17-2011 |
20110052207 | Wavelength control method and optical transmission device - An optical transmission device in which: a first cyclic filter with a fixed transmission wavelength characteristic and a second cyclic filter with a variable transmission wavelength characteristic are combined, and the transmission wavelength characteristic of the second cyclic filter is changed according to a target wavelength, to thereby control the relative phase relationship of the transmission wavelength characteristics of the first and second cyclic filters. Moreover a light source is controlled according to a monitored value of the transmittance of the second cyclic filter with respect to the control target light, to thereby match the wavelength of the control target light with the target wavelength. Consequently, it is possible, with a simple configuration using a combination of two cyclic filters, to variably control wavelength at arbitrary wavelength intervals at a high level of precision. | 03-03-2011 |
20110019956 | OPTICAL DEVICE - There is provided an optical device including a substrate having an electro-optical effect, a plurality of optical modulators including bias electrodes to which a bias voltage is applied so as to generate an electric field from one of the bias electrodes to another of the bias electrodes, and the bias electrodes of the optical modulators being disposed above the substrate, and a partition conductor to reduce influence of the electric field from the bias electrode of a first optical modulator to an optical waveguide of a second optical modulator, the partition conductor being disposed above the substrate. | 01-27-2011 |
20110008056 | Connection device and optical device - A connection device includes a ground electrode layer that is provided in a substrate, a first transmission path that is provided on the ground electrode layer via a dielectric layer, and a plurality of leads that are connected to the first transmission path and the ground electrode layer or the first transmission path and a plane that is electrically connected to the ground electrode layer. The plurality of leads are fitted into through-holes that are provided in a second transmission path and a ground electrode on a flexible substrate to be electrically connected. | 01-13-2011 |
20100329600 | Optical waveguide device - In an optical waveguide device, in a cross direction intersecting an extension direction of waveguide sections, one or more bridge portions of a ground electrode closer to a center of stress distribution of a stress due to a support member, and one or more bridge portions of a ground electrode farther from the center of stress distribution are formed with different shapes. The structure of the ground electrodes is devised so that a stress negating the difference in stress characteristics between the plurality of waveguide sections, generated by the stress applied from the support member to a substrate, is applied from the ground electrode to the substrate. | 12-30-2010 |
20100316394 | Optical receiver and jitter tolerance control method - An optical receiver includes an optical device that receives input light and converts the input light to an electric signal; an equivalent part that carries out waveform shaping on the electric signal; an amplifier that amplifies the electric signal; a discrimination part that discriminates data of the electric signal; an input optical power detecting part that detects input optical power of the input light; and a control part that makes an error rate in the electric signal with respect to the input optical power worse when the input optical power detected by the input optical power detecting part is equal to or less than a value corresponding to minimum receiver sensitivity. | 12-16-2010 |
20100316336 | Optical module having an engaging protrusion - An optical module is accommodated in a cage. The optical module includes a case that accommodates optical parts. A projection having a vertical surface perpendicular to a longitudinal direction of the case is provided on a surface of the case. A slide member includes a base part, an inclined part and a slide tab. The base part is attached on one end of the case and movable in the longitudinal direction of the case. The inclined part extends in an oblique direction from the base part. The slide tab extends in the longitudinal direction beyond the projection and is movable in the longitudinal direction within a predetermined moving range. A protruding part protruding from the surface of the case is provided on a side of the base part of the slide member with respect to the projection. | 12-16-2010 |
20100316326 | OPTICAL DEVICE HAVING OPTICAL MODULATORS - An optical device includes first and second optical modulators formed on a substrate having electro-optical effect. The first optical modulator includes a first optical waveguide; a first signal electrode configured to provide a first data signal for the first optical waveguide; and a first DC electrode, arranged at an output side of the first signal electrode, and configured to provide first DC voltage for the first optical waveguide. The second optical modulator includes a second optical waveguide; a second signal electrode configured to provide a second data signal for the second optical waveguide; and a second DC electrode provided, arranged at an input side of the second signal electrode, and configured to provide second DC voltage for the second optical waveguide. Input portions of the first and second signal electrodes are arranged at a same side edge of the substrate. | 12-16-2010 |
20100158541 | Optical communication apparatus and optical communication method - An optical communication apparatus includes a receiver configured to receive an optical signal transmitted from an optical transmitting apparatus; a detector configured to detect a predetermined pattern signal included in the optical signal; a calculator configured to calculate, based on a waveform of the predetermined pattern signal, an amount of dispersion of the predetermined pattern signal; and a compensator configured to compensate for dispersion according to the amount of dispersion. | 06-24-2010 |