Abstract: 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.

Abstract: 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.

Abstract: A first look-up table (10) outputs a result of dividing a horizontal component of a pixel address in the block by number of pixels in a horizontal component of the cell. A second look-up table (12) outputs a result of dividing a vertical component of a pixel address in the block by number of pixels in a vertical component of the cell. A third look-up table (14) outputs a residue as a result of dividing a horizontal component of a pixel address in the block by number of pixels in a horizontal component of the cell. A fourth look-up table (16) outputs a residue as a result of dividing a vertical component of a pixel address in the block by number of pixels in a vertical component of the cell. The output values of the first and second look-up tables (10,12) are addresses of the cell for burst access to the memory. The output values of the third and fourth look-up tables (14,16) are used as pixel addresses in the cell.

Abstract: A TTS preparation processing section attaches a time stamp to each of packets in an MPEG-2 TS (Transport Stream) to convert the MPEG-2 TS into an MPEG-2 TTS (Time-stamped Transport Stream). A grouping section collects a predetermined number of packets in the MPEG-2 TTS to form a group. A null packet removal section removes null packets from the group. A transmitting section shifts the MPEG-2 TTS packets in the group, from which the null packet has been removed, frontward to convert the MPEG-2 TTS packets into an RTP (Real-time Transport Protocol) packet and transmits the RTP packet to a communication line.

Abstract: One side surface of a diffraction grating is securely held by a holder, and further, the holder is securely supported on a substrate by a supporter in such a manner that the diffraction grating held by the holder is not brought into contact with the substrate. In this manner, the diffraction grating is fixed only onto one side surface to the supporter via the holder, and further, the diffraction grating is not brought into contact with the substrate. Therefore, the lower portion of the supporter is displaced by heat generated in the substrate, however, the displacement of the supporter cannot adversely influence directly on the diffraction grating since the holder is interposed between the displaced portion and the diffraction grating.

Abstract: A fade state determination unit (5) determines that the target picture is in a fade state when a feature value A is equal to or larger than a threshold value TH_A. If the target picture has been determined to be in the fade state, a fade-in determination unit (6) determines that the target picture is of a fade-in type when a feature value B is equal to or larger than a threshold value TH_B1 and a feature value C is less than a threshold value TH_C. If the target picture has been determined to be in the fade state, a fade-out determination unit (7) determines that the target picture is of a fade-out type when the feature value B is less than a threshold value TH_B2 that is smaller than the threshold value TH_B1. A cross-fade determination unit (8) determines that the target picture is of a cross-fade type when the target picture has been determined to be in the fade state and be not of the fade-in type nor of the fade-out type.

Abstract: A lens holder includes a pair of leg members inclined and extending to a lens housing from a support member that supports the lens holder at a predetermined position. A distance between pair of leg members is set such that the distance between lower end portions is equal to or larger than a width of the lens housing to be supported, and the distance between upper end portions is equal to or smaller than the width of the lens housing to be supported, and that the distance becomes gradually smaller from the lower end portions to the upper end portions of the legs. A lens optical component includes a lens housing holding a lens, and the lens holder.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: An integrated optoelectronic module comprising: a semiconductor substrate; a single-mode optical waveguide comprising a semiconductor with a signal input section at a first end; a multi-mode optical waveguide comprising a semiconductor connected to a second end of the single-mode optical waveguide; and a photodiode disposed on and adjacent to the multi-mode interferometer waveguide and having at least one optical absorption layer section, wherein the single-mode optical waveguide, the multi-mode optical waveguide, and the photodiode being stacked on the semiconductor substrate, wherein the multi-mode interferometer waveguide comprises a reflection section formed by partly grooving the multi-mode interferometer waveguide, and an optical signal having propagated through the multi-mode interferometer waveguide is reflected by the reflection section and focused on the optical absorption layer section.

Abstract: A position coordinate difference calculation section 5 calculates a position coordinate difference between a position coordinate of an output digital signal and a position coordinate of an input digital signal close to it. AN FIR coefficient memory 9 stores FIR coefficients of an FIR-LPF having such a characteristic as to cut off frequency components equal to or higher than ½ of an output sampling rate. When the position coordinate difference is input, the FIR coefficient memory outputs FIR coefficients corresponding to position coordinate differences between position coordinates of a certain number of input digital signals existing in the vicinity of the position coordinate of the output digital signal and the position coordinate of the output digital signal. AN FIR computation unit 3 performs FIR-LPF interpolation computation by using a certain number of the input digital signals and the FIR coefficients and obtains the output digital signal.

Abstract: Provided is an optical module capable of inhibiting both the displacement of an optical axis caused by thermal changes and property degradation in an optical functional circuit. The optical module includes: a planar lightwave circuit including a waveguide-type optical functional circuit and a waveguide region where only an optical waveguide is formed in contact with a side, wherein an emission end face where output light is emitted from the optical functional circuit, or an entrance end face where input light is entered to the optical functional circuit is formed in contact with the side; a fixing mount employed to hold the planar lightwave circuit only in the portion where the waveguide area is located; and an auxiliary mount employed to hold the planar lightwave circuit in contact with a side that is opposite the side where the emission end face or the entrance end face.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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 ?/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.

Abstract: 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.