Abstract: A unidirectional optical amplifier comprising an optical dielectric waveguide having a high refraction index for leading light from a light input terminal to a light output terminal and a straight electron beam transit section extended in an electron beam transit direction. The optical amplifier includes an amplifier section for amplifying light in one direction by utilizing an energy level sufficiently higher than a Fermi level, and an emissive section for emitting an electron beam in the electron beam transit section. The electron beam transit section is preferably constituted so that the effective mass of an electron in the amplifier section becomes small, and the optical dielectric waveguide and the electron beam transit section are arranged in such a manner that the wave number of light in the amplifier section becomes large and an electric field component of the light is generated in the electron beam transit direction.

Abstract: A serial interface circuit is compatible with a three-wire interface, but uses only one or two wires. One wire is a data signal line. The other wire, if present, is a scan signal line or clock signal line. If only one wire is used, the serial interface circuit detects the start of a communication period by detecting a synchronization pattern, and generates a clock signal, approximately synchronized to the clock signal used at the partner interface circuit, by dividing a higher-frequency clock signal. The partner interface circuit can operate as if a three-wire interface were being used.

Abstract: An object is to realize optical signal transmitter-receiver module with high transmitting power and high receiving sensitivity at a low cost. The optical signal transmitter-receiver module 60 includes a planar lightwave circuit (PLC) 61 and a transmitter-receiver circuit. The PLC 61 is made up with a Si substrate 62, a laser diode (LD) 6 generating the optical signal Pt, and a photodiode (PD)7 receiving the optical signal Pr. Both LD 6 and PD 7 are arranged on the Si substrate 62. The LD6 is arranged such that its front face is located in the vicinity of an optical fiber 64. The LD 6 has an optical waveguide layer that is composed of an active layer generating the optical signal Pt and a clad layer functioning as a transparent layer to the optical signal Pr. The PD 7 is arranged such that its front face is located in the vicinity of the backside face of the LD 6 and receives the optical signal Pr having passed through the optical waveguide layer of the LD 6.

Abstract: An input image that includes an eye is divided into a plurality of blocks, and a mosaic image in which each of the blocks has a density value is produced. Among all the blocks, one having a small distance from a center point of the mosaic image and having a small density value is determined to be a block including the center of the pupil of the eye. Then, based on the determined block, a center position of the pupil in the input image is derived. Based on the density value of the block including the center of the pupil, a density threshold value is set. Then, based on the density threshold value, a two-valued image is produced from the input image. Among regions in the two-valued image which are darker than the density threshold value, one including the center position of the pupil is extracted as a pupil region.

Abstract: A 1200 dpi LED may be manufactured without highly accurate mask alignment and provide good light radiation efficiency. A first interlayer dielectric is formed on a semiconductor substrate and has a plurality of first windows formed therein and aligned in a row. A diffusion region is formed in the semiconductor substrate through each of the first windows. An electrode is formed to have an area in contact with the corresponding diffusion region. Another electrode is formed on the other side of the substrate. A second interlayer dielectric is formed on the first interlayer dielectric such that the second interlayer dielectric does not overlap the area of the electrode and does not extend to a first perimeter of the area.

Abstract: A differential pulse-code modulation coder obtains an improved signal-to-noise ratio, with only a small increase in bit rate, by repetitive coding. In one aspect, the coder divides the input signal into frames, codes each frame repeatedly using different prediction coefficients or different quantizing step functions, and selects the coefficient or step function that produces the least quantization error. In another aspect, the coder repeats the coding of individual samples located in the outermost steps of the quantizing step function.

Abstract: A thin motor-driven centrifugal blowing fan apparatus draws in air in a rotation-axis direction and discharges the air in a radial direction. In this fan apparatus, blades are fitted on a peripheral face of a rotor, and each section of the blades in the vicinity of the peripheral face is implanted at an acute angle to the rotation direction so as to form an axial blade section. A section extending from the axial blade section is arranged perpendicular to the rotation direction so as to form a centrifugal blade section.

Abstract: A receiving filter of a SAW separator that prevents temperature increase, and enables to improve electric power-resisting property and attains high performance. A series arms and parallel arms of a transmitting filter and receiving filter are equipped with ladder type filters comprising SAW resonators. In the receiving filter, the number of pairs of finger electrodes of a parallel arm resonator P1 arranged at the first stage viewed from input side is larger than the number of pairs of finger electrodes of parallel arm resonators P2, . . . at other stages. Or interdigitated width of finger electrodes of the parallel resonator at the first stage is made longer than interdigitated width of finger electrodes of each of parallel resonators at other stages.

Abstract: A method of fabricating a semiconductor device comprises the steps of: (a) forming a mask layer over an upper surface of a semiconductor substrate such that the mask layer has an aperture penetrating the mask layer and having an inclined lateral wall so as to make the aperture inverted taper shaped; (b) forming a first dielectric layer at a first area over the upper surface of the semiconductor substrate within the aperture by sputtering at a first sputtering incidence direction; and (c) forming a first electrode layer at a second area over the upper surface of the semiconductor substrate within the aperture by sputtering at a second sputtering incidence direction which is different from the first sputtering incidence direction.

Abstract: The synchronizing apparatus includes a block for detecting a code from an input signal, a block for detecting from the code the variable points of the code at several times as high as the symbol rate, a block for calculating a histogram of the detected variables of the code to time, and a block for deciding that the phase number at which the calculated histogram takes the maximum value is a symbol synchronization point. This synchronizing apparatus detects the zero-cross points of an intermediate frequency band signal at N times as high as the symbol rate. It also calculates a histogram of detected time (0 to N−1). The time (0 to N−1) at which the histogram is the maximum within a predetermined detected time is selected as a symbol clock, and thereby symbol synchronization is established.

Abstract: An optical amplification medium doped with Er3+ ions is selected from the group of a fluoride glass, a chalcogenide glass, a telluride glass, a halide crystal, and a lead oxide based glass. The Er3+ ions are excited by light of at least one wavelength in the range of 0.96 &mgr;m to 0.98 &mgr;m. A laser or an optical amplifier includes this optical amplification medium doped with Er3+ ions. Furthermore, an optical amplification method performs an optical amplification using the optical amplifier having the optical amplification medium doped with Er3+ ions. Thus, the laser to be applied in the field of optical communication, the optical amplifier having the characteristics of low noise and high gain, and the optical amplification method can be provided.

Abstract: An echo canceler has an adaptive filter with coefficients grouped into segments, and a candidate value memory that stores candidate values for each segment. Signal levels in the echo canceler are monitored to determine when reinitialization is necessary. When reinitialization is necessary, the candidate values are assigned to the coefficients in the corresponding segments, and corresponding residual signals are generated. The residual signals are evaluated to select a best candidate value for each segment. The selected best candidate value is assigned to all coefficients in the corresponding segment.

Abstract: In a electrophotographic photoconductor having a single layer type photosensitive layer 3 laminated directly or through an undercoat layer 2 on an electroconductive substrate 1, the single layer type photosensitive layer 3 contains at least a resin binder, a charge generating substance, a hole transfer substance and an electron transfer substance, wherein the hole transfer substance is a compound represented by the general formula (HT1) shown below and an electrophotographic apparatus comprise this photoconductor. This electrophotographic photoconductor has good electric property in positive charge and good stability in repeated use.

Abstract: An electronic intermediary electronically connects with a tax data provider and collects electronically tax data from the tax data provider. The electronic intermediary processes the tax data collected electronically, and prepares an electronic tax return using the processed tax data. The electronic intermediary connects electronically with a taxing authority, files the electronic tax return with the taxing authority, and arranges electronically for the payment or receipt of any tax liability or refund, respectively.

Abstract: In a method of forming a scan path network, typical of the present invention, at a semiconductor integrated circuit having a clock node supplying a clock signal, a scan-in node supplying scan data and a scan-out node for receiving scan data outputted from scan flip-flops, the following steps are carried out. A plurality of scan flip-flops are placed. Delay times taken for the clock signal supplied to the clock node to reach the scan flip-flops are calculated. Distances between the scan flip-flops are calculated. Skews between the scan flip-flops are calculated. A sum of the calculated distances and the skews is calculated. The smallest value from within this total is then decided upon. The scan flip-flops are then connected across the scan-in node and the scan-out node based on this smallest value.

Abstract: A Viterbi decoding method for decoding a received signal, doing an ACS process and a trace back process a first number of times, and doing the ACS process a second number of times and the trace back process the first number of times until the trace back process is complete for all of the bits to be decoded if the tracing back has not already been finished for all bits, the Viterbi decoding method further including: after the trace back processing has finished for all of the bits to be decoded, deciding a fame error based on the result of calculating a Hamming distance between the received signal and re-encoded decoded signal, and possibly changing the first number and/or the second number depending on value stored in a counter which signifies the condition of the frame error for the past several times.

Abstract: Within a vacuum vessel 10, there are arranged an electron gun 2 emitting an electron beam and an amplification part 3 which amplifies incident light 7 by means of the energy of the electron beam. The amplification part 3 is formed by two wave-like mirrors 4 and 5 made of a metal such as Ag or a multi-layer structure of dielectric materials, said mirrors being separated from each other to constitute not only an electron beam travelling part, but also a light input part 4a, 5a, a light amplifying part 4b, 5b and a light output part 4c, 5c arranged in this order viewed in a travelling direction of the electron beam. The light is made incident upon the light input part at a given incident angle, and propagates along the wave-like or zigzag optical waveguide within the light amplifying part by repeating reflections. Therefore, the wavenumber of the light is increased, and the light is amplified in a unidirectional manner by the energy of the electron beam.

Abstract: A personalizable and programmable integrated circuit device including at least first and second programmable logic cells and at least two electrical conductive paths interconnecting the programmable logic cells, at least a portion of which can be removed for personalization of the integrated circuit device.

Abstract: In a multi-value modulation system such as M bits/1 symbol, a pattern matching apparatus is arranged by a coincident bit number detecting circuit for detecting a coincident bit number between a reception symbol and the known pattern owned by a receiver within 1 symbol; a delay circuit for delaying a detection result; and an adder. Then, a coincident bit number between the received 1 symbol (M bits) and 1 symbol (M bits) of the known pattern is detected. This detected bit number is added to each other, so that when a length of a UW pattern is N bits, the total number of adders can be reduced to N/M.

Abstract: An interferometer comprises a non-uniform beam splitter (34) which splits an incoming beam (30) of energy into two beams (36, 38). The two beams (36, 38) are taken from parts of the incoming beam (30) which overlap. The two beams (36, 38) are fed spacially separated energy feeds (44, 46) and then fed to a comparator to produce sum and difference channels (54, 58). The sum and difference channels (54, 58) are guided to a means for detecting a difference in phase (60) between the sum and difference channels (54, 58).