NTT ELECTRONICS CORPORATION Patent applications |
Patent application number | Title | Published |
20150287869 | PHOTODIODE - A photodiode that can provide a THz operation with a stable output. A photodiode having a pin-type semiconductor structure includes a semiconductor layer structure and n and p electrodes. The semiconductor layer structure is obtained by sequentially layering an n-type contact layer, a low concentration layer, and a p-type contact layer. The low concentration layer is obtained by layering an electron drift layer, a light absorption layer, and a hole drift layer while being abutted to the n-type contact layer. The n electrode and the p electrode are connected to the n-type contact layer and the p-type contact layer, respectively. During operation, the low concentration layer is depleted. | 10-08-2015 |
20150247970 | OPTICAL CIRCUIT - Disclosed is an optical circuit including a transparent plate, which is light-transmittable, and a light shielding plate, which is adhered to the transparent plate with an adhesive and has an opening through which incident light passes, and in which the aspect facing to the opening has, on the side opposite to the transparent plate, projections in an overhang shape toward the center of the opening. | 09-03-2015 |
20150205043 | OPTICAL WAVEGUIDE DEVICE AND MODULE - In a waveguide device, unnecessary optical power is appropriately terminated. According to an embodiment of the present invention, the waveguide device has a termination structure filled with a light blocking material to terminate light from a waveguide end. In the termination structure, a cladding and a core are removed to form a groove on an optical waveguide. The groove is filled with a material (light blocking material) that attenuates the intensity of light. Thus, light input to the termination structure is attenuated by the light blocking material, suppressing crosstalk which possibly effects on other optical devices. Thus, such a termination structure can restrain crosstalk occurred in optical devices integrated in the same substrate and can also suppress crosstalk which possibly effects on any other optical device connected directly to the substrate. | 07-23-2015 |
20150205042 | PLANAR LIGHTWAVE CIRCUIT - In an integrated optical receiver or transmitter, both the displacement of an optical axis caused by thermal changes and the property degradation of an optical functional circuit are inhibited. A planar lightwave circuit having a substrate and a waveguide-type optical functional circuit formed thereon composed of a material different from that of the substrate, and includes a waveguide region formed only of an optical wavelength that is in contact with a side forming an emission-end face of the optical waveguide for propagating the light emitted from the optical functional circuit or an incident-end face of an optical waveguide for propagating the light incident on the optical functional circuit. The planar lightwave circuit is fixed to a fixing mount only at the bottom of the substrate where the waveguide region is formed. | 07-23-2015 |
20150030327 | WAVELENGTH SELECTION SWITCH SYSTEM AND METHOD FOR CONTROLLING WAVELENGTH SELECTION SWITCH - A wavelength selection switch system includes a wavelength selection switch including an input port and an output port, a nonvolatile memory in which configuration information for controlling an operation of the wavelength selection switch is stored, a high-speed memory in which reading and writing can be performed at a higher speed than in the nonvolatile memory and that stores a copy of the configuration information stored in the nonvolatile memory, and a control unit that controls an operation of the wavelength selection switch based on the configuration information read from the high-speed memory, wherein the control unit periodically reads the configuration information stored in the nonvolatile memory and writes a copy of the read configuration information to the high-speed memory. | 01-29-2015 |
20140369644 | LIGHT-RECEIVING PACKAGE FOR FLAT-PLATE MOUNTING, AND OPTICAL MODULE - A light-receiving package for flat-plate mounting which can make monitor reception sensitivity of an optical signal constant without increasing the size of a module. The light-receiving package for flat-plate mounting is provided with a first subassembly in which a photo diode is fixed to a front surface of a retaining holder, a back surface of the retaining holder is a flat surface capable of moving parallel on a plane parallel to a light-receiving surface of the photo diode and a second subassembly which has a rectangular U-shaped concave holder for retaining the retaining holder, and a flat-plate base disposed on a substrate and in which a surface of the flat-plate base that is mounted on the substrate is a flat surface capable of moving parallel to a substrate surface, the rectangular U-shaped concave holder and the flat-plate base are fixed, at least one of surfaces of the concave holder having a rectangular U-shape being a flat surface is a flat surface capable of moving parallel to the back surface of the retaining holder. | 12-18-2014 |
20140233084 | PHASE MODULATION APPARATUS - A phase modulation apparatus has a light source outputting continuous light, two phase modulators, and an intensity modulator. The phase modulation apparatus is provided with an RZ phase modulation circuit, in which the phase modulators phase-modulate the continuous light from the light source with data signals input to the phase modulators and generate two phase modulation optical signals, a phase shifter shifts the phase of one phase modulation optical signal by π/2, and an intensity modulator intensity-modulates a multiplexed signal, combined with the other phase modulation optical signal, with an input clock signal CLK to convert the signal into an RZ signal, and, thus, to output the RZ signal, and a phase control circuit which adjusts the phases of the phase modulation optical signals generated by the phase modulator of the RZ phase modulation circuit so that the output of the RZ phase modulation circuit is maximum. | 08-21-2014 |
20140231627 | OPTO-ELECTRONIC INTEGRATED CIRCUIT, ARRAY ANTENNA TRANSMITTER, ARRAY ANTENNA RECEIVER, AND TRANSMITTER - An opto-electronic integrated circuit includes an optical splitter ( | 08-21-2014 |
20140183677 | OPTICAL SEMICONDUCTOR DEVICE - The present invention is intended to provide a compact and simple optical semiconductor device that reduces crosstalk (leakage current) between light receiving elements. According to the present invention, since a back surface electrode is a mirror-like thin film, crosstalk to an adjacent light receiving element can be suppressed, thereby reducing a detection error of a light intensity. By disposing a patterned back surface electrode or by disposing an ohmic electrode at the bottom of an insulating film over the whole back surface, contact resistance on the back surface can be reduced. By using the optical semiconductor elements with a two-dimensional arrangement and by using a mirror-like thin film as the back surface electrode, crosstalk can be reduced. By accommodating the optical semiconductor elements in the housing in a highly hermetic condition, the optical semiconductor elements can be protected from an external environment. | 07-03-2014 |
20140139536 | MEMORY ACCESS DEVICE - A first look-up table ( | 05-22-2014 |
20140023333 | OPTICAL COMPONENT - An optical component has first and second planar lightwave circuits. The first and second planar lightwave circuits are aligned and jointed such that the position of an i-th optical waveguide (where i is an integer greater than or equal to 1 and less than or equal to n) of the first planar lightwave circuit and that of an i-th optical waveguide of the second planar lightwave circuit are matched on a joint interface. An angle formed by the i-th optical waveguide of the first planar lightwave circuit and a normal of the interface is configured to vary in accordance with a value of i within a range satisfying the Snell's law. | 01-23-2014 |
20130313608 | SEMICONDUCTOR DEVICE - A layer in which the potential level difference normally unrequired for device operation is generated is positively inserted in a device structure. The potential level difference has such a function that even if a semiconductor having a small bandgap is exposed on a mesa side surface, a potential drop amount of the portion is suppressed, and a leakage current inconvenient for device operation can be reduced. This effect can be commonly obtained for a heterostructure bipolar transistor, a photodiode, an electroabsorption modulator, and so on. In the photodiode, since the leakage current is alleviated, the device size can be reduced, so that in addition to improvement of operating speed with a reduction in series resistance, it is advantageous that the device can be densely disposed in an array. | 11-28-2013 |
20130279854 | OPTICAL WAVEGUIDE AND ARRAYED WAVEGUIDE GRATING - This optical waveguide is provided with a slab waveguide in which a grating is formed, an arrayed waveguide connected to a position where a constructive interference portion of a self-image of the grating is formed, and a refractive index change region which is formed between the slab waveguide and the arrayed waveguide, in which an average value of a refractive index in a refractive index distribution in a direction substantially vertical to a light propagation direction is averagely increased from the slab waveguide toward the arrayed waveguide, and in which an average value of the refractive index in a refractive index distribution in a direction substantially parallel to the light propagation direction is increased at a central axis of the arrayed waveguide. | 10-24-2013 |
20130170791 | OPTICAL MODULE - A low-cost optical module with highly consistent properties. The optical module includes, in a housing, an optical waveguide array, an optical functional element array, lens optics using one or a plurality of lenses for optically coupling the optical waveguide array and the optical functional element array, and a mirror disposed so as to convert the propagation direction of optical beams transmitted by the lens optics such that the optical beams are incident on the optical incidence ports of the optical functional element array. The optical functional element array is affixed to the housing, and the angle of the mirror is fixed in place after the angle of the mirror is adjusted such that the optical waveguide array and the optical functional element array are optically coupled. | 07-04-2013 |
20130168793 | AVALANCHE PHOTODIODE - An APD is provided with the semi-insulating substrate, a first mesa having a first laminate constitution in which a p-type electrode layer, a p-type light absorbing layer, a light absorbing layer with a low impurity concentration, a band gap inclined layer, a p-type electric field control layer, an avalanche multiplier layer, an n-type electric field control layer, and an electron transit layer with a low impurity concentration are stacked in this order on a surface of the semi-insulating substrate, a second mesa having an outer circumference provided inside an outer circumference of the first mesa as viewed from the laminating direction and having a second laminate constitution in which an n-type electrode buffer layer and an n-type electrode layer are stacked in this order on a surface on the electron transit layer side, and a depletion control region that is provided in layers on the second mesa side relative to the p-type electric field control layer, formed in an encircling portion provided inside an outer circumference of the first mesa and encircling an outer circumference of the second mesa, and prevents the encircling portion of the p-type electric field control layer from being depleted when bias is applied. | 07-04-2013 |
20130154045 | AVALANCHE PHOTODIODE - An APD is provided with a semi-insulating substrate, a first mesa having a first laminate constitution in which a p-type electrode layer, a p-type light absorbing layer, a light absorbing layer with a low impurity concentration, a band gap inclined layer, a p-type electric field control layer, an avalanche multiplier layer, an n-type electric field control layer, and an electron transit layer with a low impurity concentration are stacked in this order on a surface of the semi-insulating substrate, a second mesa having an outer circumference provided inside an outer circumference of the first mesa as viewed from the laminating direction and having a second laminate constitution in which an n-type electrode buffer layer and an n-type electrode layer are stacked in this order on a surface on the electron transit layer side of the first mesa, and in the APD, a total donor concentration of the n-type electric field control layer is lower than a total acceptor concentration of the p-type electric field control layer in a range of 2×10 | 06-20-2013 |
20130136393 | OPTICAL COMPONENT - In an optical component configured to fix to a mount an optical device chip in which a plurality of waveguide type optical devices having different thermal expansion coefficients are butt-jointed, deterioration in reliability due to thermal stress is suppressed. The optical component ( | 05-30-2013 |
20130100811 | Output Rate Controller and Output Rate Control Method - An output rate controller has a TS packet buffer, a maximum value increase detector, a minimum value decrease detector and an output controller. The TS packet buffer accumulates input packets. The maximum value increase detector detects an increasing trend of the maximum number of packets being accumulated in the TS packet buffer within a fixed time period. The minimum value decrease detector detects a decreasing trend of the minimum number of packets being accumulated in the TS packet buffer within a fixed time period. The output controller sets a higher output rate of packets being accumulated in the TS packet buffer if an increasing trend has been detected by the maximum value increase detector, and sets a lower output rate of packets being accumulated in the TS packet buffer if a decreasing trend has been detected by the minimum value decrease detector. | 04-25-2013 |
20130089147 | Video Transfer System - A synchronization signal generator of a decoder adds a predetermined value to a time value, and outputs a synchronization signal when the added time value coincides with a reproducing time value in a frame. | 04-11-2013 |
20130088756 | Image Processing Device - An image processing device carries out processing in a processing unit of 3-blocks. Data of 192(=64×3)-pixels is required in the processing of 3-blocks. This is an amount of data corresponding to 16-cells. When 3-blocks and 16-cells are arranged along an scanning direction of an image, both ends of them in the scanning direction are aligned. | 04-11-2013 |
20130058608 | OPTICAL WAVEGUIDE AND ARRAYED WAVEGUIDE GRATING - A technique that does not increase the circuit size, does not make the circuit design and manufacturing difficult, and can reduce insertion loss when light enters from a slab waveguide toward an arrayed waveguide or when the light enters from the arrayed waveguide toward the slab waveguide. An optical waveguide provided with a slab waveguide in which a grating is formed therein at a distance from an end, and an arrayed waveguide whose end is connected to an end of the slab waveguide at a position where a constructive interference portion of a self-image of the grating is formed. An arrayed waveguide grating provided with a first input/output waveguide, the above-mentioned optical waveguide where an end of the slab waveguide on the opposite side of the arrayed waveguide is connected to an end of the first input/output waveguide, a second slab waveguide connected to an end of the arrayed waveguide on the opposite side of the slab waveguide, and a second input/output waveguide connected to an end of the second slab waveguide on the opposite side of the arrayed waveguide. | 03-07-2013 |
20130011095 | OPTICAL COMPONENT - In an optical component, a part of a waveguide type optical device is fixed to a convex portion of a mount. The optical component includes an optical support base, a pressure member and a pressure support base. The optical device support base is interposed between the mount and the presser member enough to be slidable in a direction parallel to surfaces of the mount and the presser member. | 01-10-2013 |
20120328236 | PLANAR LIGHTWAVE CIRCUIT - In an integrated optical receiver or transmitter, both the displacement of an optical axis caused by thermal changes and the property degradation of an optical functional circuit are inhibited. A planar lightwave circuit having a substrate and a waveguide-type optical functional circuit formed thereon composed of a material different from that of the substrate, and includes a waveguide region formed only of an optical wavelength that is in contact with a side forming an emission-end face of the optical waveguide for propagating the light emitted from the optical functional circuit or an incident-end face of an optical waveguide for propagating the light incident on the optical functional circuit. The planar lightwave circuit is fixed to a fixing mount only at the bottom of the substrate where the waveguide region is formed. | 12-27-2012 |
20120288242 | OPTICAL MODULE - An optical module including a flat-plate-shaped base having a predetermined thickness, an optical semiconductor package which is mounted on a plane of the flat-plate-shaped base to air-tightly seal an active optical element, a waveguide optical element which wave-guides light from an optical fiber or to an optical fiber and which is mounted on the plane of the flat-plate-shaped base, an optical lens which connects the optical semiconductor package and the waveguide optical element and which is mounted on the plane of the flat-plate-shaped base, and a frame-equipped lid which covers the optical semiconductor package, the waveguide optical element, and the optical lens and which is fixed onto the plane of the flat-plate-shaped base. | 11-15-2012 |
20120257855 | ARRAY-TYPE PHOTO MODULE | 10-11-2012 |
20120251041 | OPTICAL WAVEGUIDE DEVICE AND MODULE - In a waveguide device, unnecessary optical power is appropriately terminated. According to an embodiment of the present invention, the waveguide device has a termination structure filled with a light blocking material to terminate light from a waveguide end. In the termination structure, a cladding and a core are removed to form a groove on an optical waveguide. The groove is filled with a material (light blocking material) that attenuates the intensity of light. Thus, light input to the termination structure is attenuated by the light blocking material, suppressing crosstalk which possibly effects on other optical devices. Thus, such a termination structure can restrain crosstalk occurred in optical devices integrated in the same substrate and can also suppress crosstalk which possibly effects on any other optical device connected directly to the substrate. | 10-04-2012 |
20120219253 | OPTICAL CONNECTOR PLUG - An optical connector plug to be inserted to an adapter, is arranged such that a pair of engaging parts for expanding an elastic locking piece provided on a side of the adapter by a taper part and locking it with a step part is provided on a tip part of a plug frame which is a body of the plug; a locking releasing piece movable along an insertion-extraction direction is provided between the pair of engaging parts; a taper part for releasing a locking action of the elastic locking piece when extracting the plug is provided at a rear end of the locking releasing piece; and the taper part of the engaging parts has such a shape that the connecting stress is not lowered before being locked when inserting the plug. | 08-30-2012 |
20120207182 | Encoding System and Encoding Apparatus - An encoding apparatus | 08-16-2012 |
20120193740 | OPTICAL SEMICONDUCTOR DEVICE - The present invention is intended to provide a compact and simple optical semiconductor device that reduces crosstalk (leakage current) between light receiving elements. According to the present invention, since a back surface electrode is a mirror-like thin film, crosstalk to an adjacent light receiving element can be suppressed, thereby reducing a detection error of a light intensity. By disposing a patterned back surface electrode or by disposing an ohmic electrode at the bottom of an insulating film over the whole back surface, contact resistance on the back surface can be reduced. By using the optical semiconductor elements with a two-dimensional arrangement and by using a mirror-like thin film as the back surface electrode, crosstalk can be reduced. By accommodating the optical semiconductor elements in the housing in a highly hermetic condition, the optical semiconductor elements can be protected from an external environment. | 08-02-2012 |
20120155865 | OPTICAL SIGNAL TRANSMITTER, AND BIAS VOLTAGE CONTROL METHOD - An optical signal transmitter of the present invention includes: two phase modulating portions; a phase shifter which displaces carrier phases of two output lights from the phase modulating portions by π/2; a multiplexing portion which multiplexes two signal lights, carrier phases of the two signal lights being made orthogonal to each other by the phase shifter; a drive signal electrode portion which supplies a differential data signal to each of four paths of interference optical waveguides, each of the two phase modulating portions having the interference optical waveguides, the differential data signal having an amplitude which is equal to a half-wave voltage Vπ of the two phase modulating portions; a drive amplifier which amplifies the differential data signal to be supplied to each of the four paths of the interference optical waveguides; a data bias electrode portion which supplies a total of four data bias voltages to two arms, each of the two phase modulating portions having the two arms; an orthogonal bias electrode portion which supplies an orthogonal bias voltage to the phase shifter; a data bias power supply portion that adjusts delay times in the two phase modulating portions by applying the data bias voltages to the data bias electrode portion; an orthogonal bias power supply portion that adjusts a delay amount relative to a light output from at least one of the two phase modulating portions by applying the orthogonal bias voltage to the orthogonal bias electrode portion; a dither signal adding portion that adds a dither signal to at most three of the four data bias voltages; a dither detecting portion which detects a wave that is n-times a dither component from an output of the multiplexing portion (where n is an integer equal to or greater than one); and an orthogonal bias control portion which feeds back a detection result of the dither detecting portion to the orthogonal bias power supply portion. The orthogonal bias power supply portion adjusts the delay amount relative to the light output from at least one of the two phase modulating portions by controlling the orthogonal bias voltage to be applied to the orthogonal bias electrode portion based on feedback from the orthogonal bias control portion. | 06-21-2012 |
20120147910 | SEMICONDUCTOR LASER DEVICE AND DRIVING METHOD OF THE SAME - A semiconductor laser device that outputs light while periodically varying the temperature of a semiconductor laser, an optical waveguide, or a diffraction grating, outputs light while causing the optical waveguide or the diffraction grating to mechanically and periodically vary, or causes return light, which varies periodically or non-periodically, to be incident on the semiconductor laser. Since the periodical fluctuation is applied to the temperature of the semiconductor laser, the optical waveguide, or diffraction grating, the periodical mechanical variation is applied to the optical waveguide or the diffraction grating, or the return light is caused to be incident on the semiconductor laser, the semiconductor laser carries out a multimode oscillation from a low output to a high output without shifting between a single mode oscillation and a multimode oscillation. | 06-14-2012 |
20120106969 | Communications apparatus, multiplex communications apparatus, communications system, and communication method - A communications apparatus includes a transmitter that transmits signal light that is wavelength division multiplexed with other signal light and that is to be transmitted to an opposing apparatus, and a processor that is operative to change a frequency of the signal light to be transmitted by the transmitter based on detection results at the opposing apparatus and concerning variation in the frequency of the transmitted signal light. | 05-03-2012 |
20110304897 | Optical Semiconductor Module and Method for Assembling the Same - An optical semiconductor module in which displacement resulting from fixation of lenses is effectively corrected includes a first lens ( | 12-15-2011 |
20110262136 | OPTICAL DIGITAL TRANSMISSION SYSTEM - An optical digital transmission system of the present invention newly defines one second negative stuff byte in an overhead area for accommodation of the client signals with multiplexing into the OTU frame, newly defines one third positive stuff byte in a corresponding tributary slot in a payload area for accommodation of client signals with multiplexing, newly defines stuff control bits that is used for decision of the use of the second negative stuff byte and the third positive stuff byte in three different places in the overhead area for client signal accommodation with multiplexing, performs control by using the newly defined stuff control bits when accommodation of the client signal with the third positive stuff byte or the second negative stuff byte is required, and performs stuff control without using the newly defined stuff control bits when accommodation of the client signal by the third positive stuff byte and the second negative stuff byte is not required. | 10-27-2011 |
20110241150 | AVALANCHE PHOTODIODE - An electron injected APD with an embedded n electrode structure in which edge breakdown can be suppressed without controlling the doping profile of an n-type region of the embedded n electrode structure with high precision. The APD comprising a buffer layer with a low ionization rate is inserted between an n electrode connecting layer and an avalanche multiplication layer. Specifically, the APD is an electron injected APD in which an n electrode layer, the n electrode connecting layer, the buffer layer, the avalanche multiplication layer, an electric field control layer, a band gap gradient layer, a low-concentration light absorbing layer, a p-type light absorbing layer, and a p electrode layer are sequentially stacked, and a light absorbing portion that includes at least the low-concentration light absorbing layer and the p-type light absorbing layer forms a mesa shape. | 10-06-2011 |
20110229152 | Bit-Rate Discrimination Method and Its Apparatus - In the present invention, unlike a conventional circuit, discrimination is not made by integrating a logical code that includes “0” and “1” to some extent and produced from a random code, but repetition of an identical pattern of a well-known preamble signal added to a head portion of a signal is discriminated when a bit-rate of the signal is changed. More specifically, the repetition of the identical pattern is converted into a consecutive identical signal to generate the consecutive identical signal (having a length of tens bits to thousands bits). Although the consecutive identical signal is longer than a same-code continuation length included in the signal, and is shorter than a time constant necessary to the conventional circuit by about one to three digits. Therefore, an integration time can be shortened to the same degree as the generated consecutive identical signal length, and the bit-rate can be discriminated at high speed within a preamble signal receiving time. | 09-22-2011 |
20110170832 | OPTICAL TRANSCEIVER MODULE AND METHOD OF MANUFACTURING THE OPTICAL TRANSCEIVER MODULE - An optical transceiver module that is capable of being inserted into and removed from a cage includes a housing that houses a photoelectric conversion element, the housing having a guiding section formed along a front-rear direction, an operating lever that has an operating section and a lever-side contact section, the operating lever being attached to the housing in a rotatable manner about an axis of rotation; and a slider that has a wedge section that engages with a latching section provided to the cage, and a slider-side contact section that comes into contact with the lever-side contact section, the slider being guided in the front-rear direction by the guiding section, the lever-side contact section being located opposite the operating section with respect to the axis of rotation, and as the operating section is pushed rearward, the lever-side contact section pushes the slider-side contact section forward and the slider moves forward to a position where the wedge section is unlatched from the latching section. | 07-14-2011 |
20110122964 | Binary Arithmetic Coding Device - An object of the present invention is to provide a binary arithmetic coding device that allows real-time processing with a higher image quality. At a timing at which a ternary data string for a target bit is outputted, an updated coding range width and an updated range width of less probability are outputted. For that reason, while a binary conversion unit ( | 05-26-2011 |
20110064355 | WAVEGUIDE DEVICE AND MODULE - Excess optical power in a waveguide device is appropriately terminated. According to one embodiment of the present invention, the waveguide device comprises a termination structure filled with a light blocking material for terminating light from the end section of a waveguide. This termination structure can be formed by forming a groove on an optical waveguide by removing the clad and core, and filling the inside of that groove with a material attenuating the intensity of the light (light blocking material). In this manner, light that enters into the termination structure is attenuated by the light blocking material, and influence on other optical devices as a crosstalk component can be suppressed. With such termination structure, not only the influence on optical devices integrated on the same substrate, but also the influence on other optical devices directly connected to that substrate can be suppressed. | 03-17-2011 |
20110033193 | MODULATION METHOD, MODULATION PROGRAM, RECORDING MEDIUM, MODULATION DEVICE, AND OPTICAL TRANSMITTER - A modulation method according to the invention is applied to a modulation device in which a light source is driven by a differential signal while a modulation circuit and the light source are capacitively coupled. In the modulation method of the invention, when an average potential fluctuates at an input terminal of the light source, a potential fluctuation is externally provided using a control circuit such that a normal phase side and a reverse phase side become equal to each other in a time constant of the fluctuation in average potential, and transient states of the average potentials at the normal phase side and reverse phase side are equalized and cancel each other as in-phase components of a signal input to the light source, which allows an optical signal to be normally transmitted from the light source. The optical signal can normally be transmitted from the light source even before the average potentials at a normal phase input terminal and a reverse phase input terminal of the light source are stabilized. | 02-10-2011 |
20100322569 | OPTICAL MODULE - An optical module has a structure for reducing the stress applied to a package. The optical module is structured so that an end face of a waveguide ( | 12-23-2010 |
20100296766 | SEMICONDUCTOR OPTICAL MODULATOR - The present invention can provide an npin-type optical modulator that has a high withstand voltage and is easily fabricated. A semiconductor optical amplifier ( | 11-25-2010 |
20100188724 | WAVELENGTH-SELECTIVE SWITCH - A wavelength-selective switch with a switch unit having a lens array, a first lens and a beam expander, and a branching unit having a second lens, a diffraction grating, a third lens and a mirror, in which the switch unit and the branching unit are accommodated in independent casings, and a confocal point of the light transmitted through the first lens and the light transmitted through the second lens are arranged on a connecting surface of the casing of the switch unit and the casing of the branching unit. | 07-29-2010 |
20100163925 | AVALANCHE PHOTODIODE - In an electron-injection type APD, it is necessary to prevent a dark current increase and to secure the life time of the device. It is demanded to improve reliability of the APD with a lower production cost. With the InP buffer layer having an n-type doping region on the inside of a region defined by an optical absorption layer, a predetermined doping profile is achieved by ion implantation. Thus, electric field concentration in the avalanche multiplication layer is relaxed. Furthermore, a low-concentration second optical absorption layer is provided between the optical absorption layer and the avalanche multiplication layer. Responsivity of the optical absorption layer is maximized, and depletion of the lateral surface of the optical absorption layer is prevented; thus, electric field concentration is prevented. Preventing edge breakdown, the device improves its reliability. | 07-01-2010 |
20100105323 | Electric-Field Communication Device - A signal electrode ( | 04-29-2010 |
20100053720 | LIGHT SOURCE APPARATUS WITH MODULATION FUNCTION AND ITS DRIVING METHOD - A light source apparatus with modulation function has a wavelength conversion module ( | 03-04-2010 |
20100008626 | OPTICAL CHIP FOR ARRAYED WAVEGUIDE GRATING TYPE OPTICAL MULTIPLEXER/DEMULTIPLEXER CIRCUIT, WAVEGUIDE SUBSTRATE, AND METHOD FOR FABRICATING OPTICAL CHIP FOR ARRAYED WAVEGUIDE GRATING TYPE OPTICAL MULTIPLEXER/DEMULTIPLEXER CIRCUIT - An optical chip according to the present invention is formed into a projecting shape expanded toward either side at the center. A waveguide substrate has a layout in which arrayed waveguide grating type optical multiplexer/demultiplexer circuits, each having a curve direction of an array waveguide reverse to each other, are arranged in combination, and the optical chips are cut out of the waveguide substrate. A method for fabricating the optical chip according to the present invention can enhance an optical chip yield rate, and further, can fabricate an optical chip having the shape for stabilizing optical characteristics of the arrayed waveguide grating type optical multiplexer/demultiplexer circuit. | 01-14-2010 |
20090316742 | SEMICONDUCTOR LASER DEVICE AND DRIVING METHOD OF THE SAME - A semiconductor laser device according to the present invention outputs light while periodically varying the temperature of a semiconductor laser, an optical waveguide, or a diffraction grating, outputs light while causing the optical waveguide or the diffraction grating to mechanically and periodically vary, or causes return light, which varies periodically or non-periodically, to be incident on the semiconductor laser. Since the periodical fluctuation is applied to the temperature of the semiconductor laser, the optical waveguide, or diffraction grating, the periodical mechanical variation is applied to the optical waveguide or the diffraction grating, or the return light is caused to be incident on the semiconductor laser, the semiconductor laser carries out a multimode oscillation from a low output to a high output without shifting between a single mode oscillation and a multimode oscillation. Accordingly, the present invention can provide a semiconductor laser device having IL characteristics in which a current is proportional to a light output and a driving method thereof. | 12-24-2009 |
20090238266 | TRANSCODER - A category setting part sets a type of a decoded image based on characteristics of the decoded image which are fineness of the decoded image and an intensity of movement of the decoded image. A code amount setting part sets a target code amount of an output image based on the type of the decoded image. A quantization step value setting part sets a quantization step value of the output image based on the target code amount of the output image. A transcoder can set the target code amount of the output image depending on fineness of the decoded image. The transcoder can distribute the target code amount of the output image to a reference image and a predicted image depending on the intensity of movement of the decoded image. | 09-24-2009 |
20090237569 | TRANSCODER - A scene change detection part detects a scene change based on a characteristic amount of an input image. A target code amount setting part executes correction by a correction code amount on a target code amount previously set for suppressing variation of an output code amount around the time of scene change. A quantization step value setting part sets a quantization step value based on the target code amount. That is to say, a transcoder | 09-24-2009 |
20090174819 | MOTION VECTOR DETECTION DEVICE AND MOTION VECTOR DETECTING METHOD - It is an object to reduce an amount of calculation for motion vector detection and to prevent degradation in image quality. A motion vector detection device ( | 07-09-2009 |
20090009370 | TRANSCODER - A transcoder calculates a reference conversion factor on the basis of a ratio between a total target bit rate of a whole second stream and an total input bit rate of a whole first stream and calculates a coefficient of variation from the total target bit rate of the whole second stream and an average output bit rate of a converted second stream in the N period. Next, a quantization step conversion factor in the next (N+1) period is calculated by adding the coefficient of variation to the reference conversion factor. Then, a quantization step value of a second stream in the (N+1) period is calculated by multiplying a quantization step value of a first stream in the (N+1) period by the quantization step conversion factor. | 01-08-2009 |
20080304786 | Semiconductor optoelectronic waveguide - The present invention relates to a semiconductor optoelectronic waveguide having a nin-type hetero structure which is able to stably operate an optical modulator. On the upper and lower surfaces of the core layer determined for the structure so that electro-optical effects are effectively exerted at an operating light wavelength and are provided with intermediate clad layers having a band gap which is greater than that of the core layer | 12-11-2008 |
20080226298 | Optical Transmission System - The present invention has been achieved to provide a novel optical transmission system realizing high-speed optical transmission over greater distance by suppressing waveform degradation caused by mode dispersion and mode transition in a multimode optical transmission line. The optical transmission system of the present invention includes: an optical transmitter for transmitting incoherent light; an excitation mechanism for exciting a predetermined mode in the incoherent light transmitted from the optical transmitter; a multimode optical transmission line for transmitting the incoherent light transmitted from the excitation mechanism; a transmission mechanism for transmitting a predetermined mode in the incoherent light transmitted from the excitation mechanism; and an optical receiver for receiving the incoherent light transmitted from the transmission mechanism or the incoherent light transmitted from the transmission mechanism. | 09-18-2008 |
20080226290 | OPTICAL SIGNAL MONITORING APPARATUS, OPTICAL SYSTEM AND OPTICAL SIGNAL MONITORING METHOD - By reducing the number of PD arrays, and by simplifying the configuration of an optical power monitor in a WDM system, a miniaturized, cost reduced optical signal monitoring apparatus, optical system or optical signal monitoring method is provided. An optical power monitor | 09-18-2008 |