Patent application number | Description | Published |
20080199130 | ARRAYED WAVEGUIDE GRATING - The present invention enables reduction of the temperature dependence of the light transmission center wavelength of the arrayed waveguide grating. | 08-21-2008 |
20080239465 | DELAY-LINE DEMODULATOR AND METHOD OF ADJUSTING A PHASE SHIFT IN THE DEMODULATOR - In a method of phase adjustment for the demodulator | 10-02-2008 |
20080240645 | OPTICAL INTEGRATED CIRCUIT AND OPTICAL INTEGRATED CIRCUIT MODULE - An optical integrated circuit | 10-02-2008 |
20080240727 | TUNABLE DISPERSION COMPENSATOR - The tunable dispersion compensator | 10-02-2008 |
20080253716 | ARRAYED WAVEGUIDE GRATING OPTICAL MULTIPLEXER/DEMULTIPLEXER - An arrayed waveguide grating optical multiplexer/demultiplexer | 10-16-2008 |
20090097101 | DELAY-LINE DEMODULATOR - Problem to be Solved To provide a delay-line demodulator of which the divergence amount of polarization is reduced. | 04-16-2009 |
20090110393 | BROADBAND WAVELENGTH MULTIPLEXING AND DEMULTIPLEXING FILTER AND OPTICAL SPLITTER WITH OPTICAL SIGNAL MULTIPLEXING AND DEMULTIPLEXING FUNCTION - Two Mach-Zehnder optical interferometer circuits | 04-30-2009 |
20100046064 | DELAY DEMODULATION DEVICES - A delay demodulation device, which reduces chip size and polarization dependent frequency (PDf), is provided. The delay demodulation device comprises: an input waveguide, which receives DQPSK signals; a Y-shape waveguide, which splits the input waveguide; a first Mach-Zehnder interferometer; and a second Mach-Zehnder interferometer. Both end of two arm waveguides of first Mach-Zehnder interferometer and both ends of two arm waveguides of second Mach-Zehnder interferometer are angled toward the center portion of a Planar Lightwave Circuit (PLC). Because of the angle, the length of the two arm waveguides of the first Mach-Zehnder interferometer and the length of the two arm waveguides of the second Mach-Zehnder interferometer in Z-direction can be shortened, and input couplers and output couplers of the Mach-Zehnder interferometers in Z-direction can be shortened as well. The area occupied by the Mach-Zehnder interferometers is also reduced. | 02-25-2010 |
20100053731 | DELAY DEMODULATION DEVICES - Delay demodulation devices with optimized temperature and pressure distribution on a Planar Lightwave Circuit (PLC) are provided. The delay demodulation device | 03-04-2010 |
20100067098 | METHODS TO CONTROL PHASE SHIFTS OF DELAY DEMODULATION DEVICES - The present invention provides methods to control phase shift of delay demodulation devices to reduce Polarization Dependent wavelength (PDλ) to be less than, for example, 0.5 GHz (i.e. 0.004 nm). The method to control phase shift in a Planar Lightwave Circuit (PLC) for demodulating Differential Quadrature Phase Shift Keying (DQPSK) comprising two Mach-Zehnder interferometers, each having two arm waveguides and heaters placed on the two arm waveguides, the method comprising the steps of: (first step) supplying electricity to at least one predetermined heater on the two arm waveguides of each Mach-Zehnder interferometer such that Polarization Dependent wavelength (PDλ) is reduced as electricity is supplied to the predetermined heaters; (second step) inserting a half-wave plate in the two arm waveguides of each Mach-Zehnder interferometer after PDλ is reduced in the first step; (third step) supplying electricity to the predetermined heater on the at least one of the two Mach-Zehnder interferometers used in the first step to control phases of the DQPSK signals after the half-wave plates are inserted. | 03-18-2010 |
20100073760 | DELAY-LINE DEMODULATOR - A delay-line demodulator for demodulating a differential quadrature phase shift keying (DQPSK) signal is provided. The demodulator includes two Mach-Zehnder interferometers individually comprising two waveguides having different lengths therebetween and through which a light signal branched from the DQPSK signal propagates, respectively. A phase of the light signal propagating at one of the waveguides is delayed as compared to a phase of the light signal propagating at another one of the waveguides, wherein a divergence amount of polarization is adjusted by driving sets of heaters that are facing each other and sandwiching a half wavelength plate therebetween. | 03-25-2010 |
20100111468 | OPTICAL INTEGRATED CIRCUIT AND OPTICAL INTEGRATED CIRCUIT MODULE - An optical integrated circuit includes a planar lightwave circuit, and a semiconductor element, which are fixed at one contact surface. A semiconductor optical amplifier (SOA) and a turnaround waveguide having a turnaround portion are formed on a semiconductor substrate. The turnaround waveguide is turned around on the second substrate and is connected to an output port of the SOA. An input port and an output port of the turnaround waveguide are optically coupled at the contact surface with an input port and an output port of the optical waveguides respectively. | 05-06-2010 |
20100142900 | SSC CHIP, FIBER ARRAY ATTACHED WITH SSC, PLC MODULE ATTACHED WITH SSC AND METHOD FOR MANUFACTURING SSC - There is provided a SSC chip whose yield may be improved and whose processing steps may be simplified as compare to those of a prior art PLC chip having a light waveguide circuit to which a spot-size converter (SSC) is added, a fiber array attached with the SSC chip, a PLC module attached with the SSC chip and a method for manufacturing the SSC chip. The SSC chip has four spot-size converters and is fabricated separately from a PLC chip. Each SSC has a straight waveguide having the same core width and height with an end of an input/output waveguide of the PLC chip, a horizontally tapered waveguide in which the core width is enlarged in a tapered shape in the horizontal direction from the core width of the straight waveguide, a vertically tapered waveguide in which the core height is enlarged in a tapered shape in the vertical direction from the core height of the horizontally tapered waveguide and a spot-size enlarged portion whose core width and core height are both enlarged. Because it is unnecessary to fabricate the SSC at the end of the input/output waveguide of the PLC chip, a yield of the PLC chip may be improved. | 06-10-2010 |
20100278483 | ATHERMAL AWG MODULE - An athermal AWG module | 11-04-2010 |
20100303410 | ARRAYED WAVEGUIDE GRATING - An arrayed waveguide grating includes: at least one input waveguide; an input slab waveguide connected to the input waveguide; a plurality of output waveguides; an output slab waveguide connected to the output waveguides; and an arrayed waveguide. The arrayed waveguide includes: M channel waveguides connected between the input slab waveguide and the output slab waveguide; and a phase correcting portion configured to provide a predetermined phase to at least a part of the M channel waveguides by a form of the at least the part of the M channel waveguides being changed. | 12-02-2010 |
20110008002 | ARRAYED-WAVEGUIDE-GRATING-TYPE OPTICAL MULTIPLEXER/DEMULTIPLEXER - A multiplexer/demultiplexer includes: a waveguide chip including a first chip and a second chip that are divided by a plane and obtained by cutting, together with a substrate, in a direction crossing an optical axis, a first slab waveguide of an AWG including the first slab waveguide and a second slab waveguide that are formed on the substrate; a first base to which the first chip is fixed; a second base separated from the first base and to which the second chip is fixed; and a member that has one end fixed to the first base or chip and another end fixed to the second base or chip, in a state in which cut surfaces of the first and second chips face each other, and that is configured to move the first base and the second base relatively to each other along the plane by expanding/contracting when temperature changes. | 01-13-2011 |
20110085761 | ARRAYED WAVEGUIDE GRATING AND METHOD OF MANUFACTURING ARRAYED WAVEGUIDE GRATING - An arrayed waveguide grating includes: at least one first waveguide; a first slab waveguide connected to the at least one first waveguide; a plurality of second waveguides; a second slab waveguide connected to the plurality of second waveguides; and an arrayed waveguide. The arrayed waveguide includes: M channel waveguides connected between the first slab waveguide and the second slab waveguide, wherein M is a natural number; and a phase correcting portion configured to provide a predetermined phase to at least a part of the M channel waveguides by one or both of a width and a length of the at least the part of the M channel waveguides being changed. | 04-14-2011 |
20110097035 | BROADBAND WAVELENGTH MULTIPLEXING AND DEMULTIPLEXING FILTER AND OPTICAL SPLITTER WITH OPTICAL SIGNAL MULTIPLEXING AND DEMULTIPLEXING FUNCTION - Two Mach-Zehnder optical interferometer circuits | 04-28-2011 |
20110110622 | HYBRID INTEGRATED OPTICAL MODULE - The present invention provides a hybrid integrated optical module having a high coupling efficiency by suppressing a connection loss between waveguides. A hybrid integrated optical module according to an embodiment of the present invention is an optical module which integrates a semiconductor chip and a PLC chip. The semiconductor chip has a semiconductor waveguide and is mounted on a Si bench. The PLC chip includes a PLC substrate and an optical waveguide formed on the PLC substrate. An end face of the semiconductor chip protrudes from an end face of the Si bench toward the PLC chip side by a protrusion amount X. Gap adjustment (adjustment of a distance D) between the semiconductor waveguide and the optical waveguide becomes possible by setting a position where the end face of the semiconductor chip is brought into contact with an end face of the PLC chip to be a reference position (zero point). | 05-12-2011 |
20110123153 | ARRAYED WAVEGUIDE GRATING - An arrayed waveguide grating includes input waveguides, an input slab waveguide, n output waveguides, an output slab waveguide, and an arrayed waveguide. Gaps are formed in the output waveguides other than the output waveguides of both sides of an array of the output waveguides, respectively, such that loss increases toward the central side of the array. Sizes of the gaps in the output waveguides increase toward the central side of the array. | 05-26-2011 |
20120002918 | WAVELENGTH MULTIPLEXER/DEMULTIPLEXER AND METHOD OF MANUFACTURING THE SAME - The present invention provides a wavelength multiplexer/demultiplexer comprising a Mach-Zehnder interferometer and an arrayed waveguide diffraction grating, the wavelength multiplexer/demultiplexer having a simple configuration and being capable of reducing the degradation in the temperature compensation characteristics of a temperature compensation material provided in the Mach-Zehnder interferometer or the peeling-off of the temperature compensation material, and a method of manufacturing the same. A wavelength multiplexer/demultiplexer comprises an AWG including two separated slab waveguides and an MZI including two arm waveguides. A temperature compensation groove is formed in the two arm waveguides, wherein in a space between the temperature compensation groove, and two separated slab waveguides, a compensation material, the refractive index matching that of the AWG or Mach-Zehnder interferometer, the compensation material having a temperature dependence coefficient with a sign different from that of the temperature dependence coefficient of the waveguide core and having plasticity or fluidity, is filled. | 01-05-2012 |
20120014636 | WAVEGUIDE-TYPE OPTICAL CIRCUIT - A waveguide-type optical circuit comprises an optical coupler being an optical branch coupler constructed from waveguide cores which are closely arranged each other, and dummy patterns that lay along sides of the waveguide cores in the optical coupler for preventing optical major axes of the waveguide cores from inclining. | 01-19-2012 |
20120154901 | PLC-TYPE DELAY DEMODULATION CIRCUIT - A PLC-type delay demodulation circuit includes a planar lightwave circuit that is provided on one PLC chip and demodulates a DQPSK signal. The planar lightwave circuit includes a Y-branch waveguide that branches a DQPSK-modulated optical signal into two optical signals and first and second MZIs that delay the branched optical signals by one bit. The length of a short arm waveguide of the first MZI is different from the length of a short arm waveguide of the second MZI, and the length of an optical path from the Y-branch waveguide to output ports of the first MZI through the short arm waveguide of the first MZI is equal to that of an optical path from the Y-branch waveguide to output ports of the second MZI through the short arm waveguide of the second MZI. | 06-21-2012 |
20120162746 | PLC-TYPE DELAY DEMODULATION CIRCUIT - The PLC-type delay demodulation circuit includes a planar lightwave circuit that is provided on one PLC chip and demodulates a DQPSK signal. The planar lightwave circuit includes a Y-branch waveguide that branches a DQPSK-modulated optical signal into two optical signals and first and second MZIs that delay the branched optical signals by one bit. A wave plate is provided in central portions of first and second arm waveguides of the first MZI and first and second arm waveguides of the second MZI in such a manner that the wave plate intersects all of the four arm waveguides, the four arm waveguides being close to one another in a portion where the wave plate is provided. | 06-28-2012 |
20120195552 | ARRAYED WAVEGUIDE GRATING TYPE OPTICAL MULTIPLEXER AND DEMULTIPLEXER - An arrayed waveguide grating type optical multiplexer and demultiplexer which achieves a low crosstalk even when temperature changes is provided, comprising, on a substrate, a waveguide chip in which an arrayed waveguide grating is formed that has a first waveguide, a first slab waveguide, an arrayed waveguide, a second slab waveguide, and a second waveguide, the waveguide chip being divided into two by any of the first and second slab waveguide, and includes a first glass plate to which one side of the arrayed waveguide grating divided into two in the waveguide chip is fixed, a second glass plate to which the other side thereof is fixed, and a compensation member compensating a temperature dependent shift of a light transmission center wavelength of the arrayed waveguide grating, wherein a part for the arrayed waveguide is not fixed to any of the first and second glass plates. | 08-02-2012 |
20120195553 | ARRAYED WAVEGUIDE GRATING TYPE OPTICAL MULTIPLEXER AND DEMULTIPLEXER - An arrayed waveguide grating type optical multiplexer and demultiplexer which reduces a package size although plural arrayed waveguide gratings are included, is provided, comprising plural arrayed waveguide gratings which are provided in parallel to one another on a substrate and each of which has a first waveguide, a first slab waveguide, an arrayed waveguide, a second slab waveguide, and a second waveguide, and also includes a waveguide chip divided into a first and second separated waveguide chip in the first or second slab waveguide in each of the arrayed waveguide gratings and a compensation member compensating a temperature dependent shift of a light transmission center wavelength in the arrayed waveguide grating by relatively moving the first and second waveguide chip when expanded or contracted according to a temperature change. The waveguide chip has a shape bending along a bending direction of the arrayed waveguide. | 08-02-2012 |
20120207474 | PLC-TYPE DEMODULATOR AND OPTICAL TRANSMISSION SYSTEM - The invention provides a PLC-type DP-QPSK demodulator that reduces connection loss between a polarization beam splitter and a 90-degree hybrid circuit and aims at reducing the manufacturing cost and an optical transmission system using the same. In an embodiment of the invention, a PLC-type DP-QPSK demodulator that receives a DP-QPSK signal includes one PLC chip having a planar lightwave circuit. Input ports and output ports of signal light are provided at an input end and at an output end of the PLC chip, respectively. Within the planar lightwave circuit, there are integrated a polarization beam splitter that splits the DP-QPSK signal into an X-polarization QPSK signal and a Y-polarization QPSK signal, and two 90-degree hybrid circuits that mix the X-polarization QPSK signal and local oscillation light and the Y-polarization QPSK signal and local oscillation light, respectively, split each QPSK signal into orthogonal components I, Q and output them. | 08-16-2012 |
20120224812 | 90-DEGREE HYBRID - The present invention provides a 90-degree hybrid capable of miniaturization and also capable of a stable operation in a wide band. According to an embodiment of the present invention, a PLC-type 90-degree hybrid comprises: a PLC chip having a planar lightwave circuit formed therein; and a 90-degree hybrid circuit formed in the planar lightwave circuit, mixing a modulated signal light and an LO light to separate the signal light into quadrature components I and Q, and outputting the same. The 90-degree hybrid circuit includes: two Y-branch couplers each branching the signal light and the LO light; and two wavelength-independent directional couplers which cause LO lights passing through two paths and signal lights passing through two paths to interfere with each other, respectively. The above-described paths include waveguides having mutually inverted shapes and waveguides having an identical shape, and have a shape substantially symmetrical with respect to the signal light. | 09-06-2012 |
20120251046 | OPTICAL WAVEGUIDE CIRCUIT - The present invention provides an optical waveguide circuit which includes: a waveguide made of a material whose temperature coefficient of refractive index has a second-order component; a groove formed in a part of the waveguide; and a compensation material having a temperature coefficient of refractive index different from the temperature coefficient of refractive index of the waveguide, and in which a normal line of an interface between the groove and the waveguide, and an optical axis of light propagating through the waveguide intersect at a predetermined intersection angle, and the predetermined intersection angle is determined so as to reduce a second-order component of optical path length change of the waveguide due to the second-order component of temperature coefficient of the refractive index of the waveguide. | 10-04-2012 |
20120251047 | MACH-ZEHNDER INTERFEROMETER-ARRAYED WAVEGUIDE GRATING AND PLANAR LIGHT-WAVE CIRCUIT CHIP - The present invention provides a Mach-Zehnder interferometer-arrayed waveguide grating (MZI-AWG) and a planar light-wave circuit chip in which a certain number of chips can be secured without degradation of MZI-AWG characteristics. An MZI-AWG ( | 10-04-2012 |
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 |
20130114929 | ARRAYED WAVEGUIDE GRATING - An arrayed waveguide grating includes input waveguides, an input slab waveguide, n output waveguides, an output slab waveguide, and an arrayed waveguide. Gaps are formed in the output waveguides other than the output waveguides of both sides of an array of the output waveguides, respectively, such that loss increases toward the central side of the array. Sizes of the gaps in the output waveguides increase toward the central side of the array. | 05-09-2013 |
20130121632 | SOA-PLC HYBRID INTEGRATED POLARIZATION DIVERSITY CIRCUIT AND METHOD FOR MANUFACTURING THE SAME - The invention of the present application provides an SOA-PLC hybrid integrated polarization diversity circuit including a PLC-PBS chip and an SOA-COS whose respective waveguides are coupled to each other. The PLC-PBS chip includes: first and second optical waveguides; a Mach-Zehnder interferometer circuit; and a half-wave plate placed in the first optical waveguide which TM mode light is split into. The SOA-COS includes: a third optical waveguide connected to the first optical waveguide; a fourth optical waveguide connected to the second optical waveguide; and an SOA formed in at least one of the third and fourth optical waveguides. One end of the third optical waveguide and one end of the fourth optical waveguide are connected to a U-turn optical waveguide, the one ends being not connected to the first optical waveguide and the second optical waveguide, respectively. | 05-16-2013 |
20130129273 | POLARIZATION SEPARATION ELEMENT AND OPTICAL INTEGRATED ELEMENT - A polarization separation element of an optical waveguide type formed on a substrate includes: an input-light demultiplexer; an output-light multiplexer; a first arm waveguide and a second arm waveguide that connect the input-light demultiplexer and the output-light multiplexer, each of the first and second arm waveguides including an optical waveguide having birefringence; and at least one heating unit formed above each of the first arm waveguide and the second arm waveguide, wherein a geometric length of the second arm waveguide is larger than a geometric length of the first arm waveguide by equal to or less than a degree corresponding to an amount of increase in an optical path length generated in the first arm waveguide when the at least one heating unit performs heating on the first arm waveguide to impart birefringence to the first arm waveguide. | 05-23-2013 |
20130142483 | ARRAYED WAVEGUIDE GRATING MULTIPLEXER-DEMULTIPLEXER - A multiplexer-demultiplexer including: an AWG chip including a first input-output waveguide, a first slab waveguide connected thereto, an arrayed waveguide connected thereto and formed of parallel channel waveguides of different lengths, a second slab waveguide connected thereto, and second input-output waveguides connected thereto; a base plate joined to an underside of the chip; a fixed piece and a movable piece formed by the chip and the base plate being cut across the first or second slab waveguide; a reference plate to which the fixed piece is joined and against which the movable piece is abutted; a member bridging between these pieces and compensating a temperature-dependent shift of a light transmission center wavelength of the multiplexer-demultiplexer by expanding/contracting according to a temperature change and changing relative positions of the pieces; and a clip sandwiching the reference plate and the movable piece allowing the piece to slide on the plate. | 06-06-2013 |
20130208348 | PLC-TYPE DELAY DEMODULATION CIRCUIT - A PLC-type delay demodulation circuit includes a planar lightwave circuit that is provided on one PLC chip and demodulates a DQPSK signal. The planar lightwave circuit includes a Y-branch waveguide that branches a DQPSK-modulated optical signal into two optical signals and first and second MZIs that delay the branched optical signals by one bit. The length of a short arm waveguide of the first MZI is different from the length of a short arm waveguide of the second MZI, and the length of an optical path from the Y-branch waveguide to output ports of the first MZI through the short arm waveguide of the first MZI is equal to that of an optical path from the Y-branch waveguide to output ports of the second MZI through the short arm waveguide of the second MZI. | 08-15-2013 |
20130209111 | DEMODULATING DELAY CIRCUIT AND OPTICAL RECEIVER - A demodulating delay circuit with a planar lightwave circuit includes: an optical interferometer including input and output couplers, and a first arm waveguide connecting the couplers, and a shorter second arm waveguide. The interferometer delays each bit of a signal by one bit such that the delayed bit interferes with its adjacent bit, and has a bent form such that propagation directions of light in the couplers are different by 180 degrees. The couplers each include first and second waveguides. The first waveguide is longer and the waveguides are closely arranged in parallel at two positions thereby forming directional couplers. The input and output couplers are each configured as a wavelength insensitive coupler having a coupling ratio of 50 percent in a bandwidth used. The first waveguide of the input coupler is arranged on the same side as that on which the first waveguide of the output coupler is arranged. | 08-15-2013 |
20130236136 | OPTICAL WAVEGUIDE CIRCUIT - An optical waveguide circuit includes a polarization beam splitter connecting to a first input optical waveguide; an optical interference element receiving one of orthogonally polarization-split lights of a first light from the polarization beam splitter, and one of orthogonally-polarized lights from a second light input to a second input optical waveguide, the optical interference element causing interference therebetween; a first connection optical waveguide connecting the polarization beam splitter and the optical interference element; and a second connection optical waveguide connecting the second input optical waveguide and the optical interference element. The first and the second input optical waveguides have a straight-line shape or an S-shape including a first bending portion and a second bending portion to cancel the polarization-rotation of light taking place in the first bending portion. The polarization beam splitter, the first and the second connection optical waveguides, and the optical interference element are arranged in an S-shape. | 09-12-2013 |
20130330041 | WIDE-BAND OPTICAL COUPLER - The present invention aims to provide a low-wavelength-dependent optical coupler capable of concurrently achieving high process stability and low polarization dependence. An optical coupler | 12-12-2013 |
20130330042 | OPTICAL BRANCHING ELEMENT AND OPTICAL BRANCHING CIRCUIT - An optical branching element includes: an input waveguide; a tapered waveguide connected to the input waveguide; two branched waveguides that are connected to the tapered waveguide and arranged so as to form a Y-shape with the input waveguide and the tapered waveguide; and a plurality of strip-like waveguides that are provided so as to connect between the two branched waveguides and not to protrude outside the two branched waveguides, and formed so as to decrease in width as becoming distant from the tapered waveguide. | 12-12-2013 |
20140078580 | OPTICAL AMPLIFIER DEVICE - An optical amplifier device comprising an input/output section that inputs incident light and outputs emission light; a polarized light splitting section that causes a polarized light component of the incident light input from the input/output section to branch, and outputs first polarization mode light having a first polarization and second polarization mode light having a second polarization different from the first polarization; a polarization converting section that receives the first polarization mode light, converts the first polarization to the second polarization, and outputs first polarization converted light; and an optical amplifying section that amplifies the first polarization converted light input to one end of a waveguide, outputs the resulting amplified first polarization converted light from another end of the waveguide, amplifies the second polarization mode light input to the other end of the waveguide, and outputs the resulting amplified second polarization mode light from the one end of the waveguide. | 03-20-2014 |
20140241683 | OPTICAL WAVEGUIDE ELEMENT AND METHOD OF PRODUCING THE SAME - An optical waveguide element includes a cladding portion made of a silica-based glass, and an optical waveguide positioned in the cladding portion and made of a silica-based glass in which a ZrO | 08-28-2014 |