Abstract: Intraframe coding and decoding equipment are used in a communication network for digital video signals. Video signal sources which have various frequency deviations are transmitted by the communication network. Each of the intraframe coding and decoding equipment items has a locked sampling coding algorithm which is suitable for an input video signal with high frequency precision and a nonlocked sampling coding algorithm which is suitable for an input video signal with low frequency precision. It is determined whether or not the frequency precision (i.e., the frequency deviation of the sync signal) falls within a predetermined range. One of the coding algorithms is selected in accordance with a detection result. The coding algorithm can be selected in accordance with a decoding algorithm of a receiving-side equipment. Switching of the coding algorithms is performed simultaneously with switching of the clock signals of the locked and unlocked sampling clocks.

Abstract: An input multi-level amplitude signal of 2.sup.M levels is supplied via a DC level controller to an AD converter for conversion into an N-bit (N being an integer greater than M) digital signal, and M high-order bits of the digital signal are provided as decided outputs. It is decided by a decision means whether a deviation of the DC level of the multi-level amplitude signal at the input side of the AD converter is in excess of a predetermined value. When the deviation of the DC level is decided less than the predetermined value, the outputs of bits less significant than the Mth bit in the digital signal are integrated for input as a DC level control signal into the DC level controller, correcting the deviation of the DC level.

Abstract: A double-channel planar buried-heterostructure semiconductor laser diode (DC-PBH LD) has improved high frequency response characteristics due to lower p-n junction capacitance resulting from the interposition of a low carrier concentration blocking layer between p-n-p-n blocking layers of the DC-PBH LD structure.

Abstract: The quality of a compound semiconductor crystal such as gallium arsenide used for an integrated circuit is upgraded by a method comprising optionally forming a protective film on the obverse surface and reverse surface of a substrate consisting of a compound semiconductor crystal, subjecting the substrate to a heat treatment in an inert atmosphere at a temperature of at least the same as the activating temperature after the ion implantation into the substrate and then optionally revmoving the protective film.

Abstract: A digital data code conversion circuit for a variable-word-length data code includes a data code conversion portion and a preparation circuit. In the preparation circuit, a variable-word-length data code having a word length greater than a number n is divided into a plurality of variable-word-length data codes having a word length less than or equal to the number n. The divided variable-word-length data codes are converted into fixed-word-length data codes having a word length n in the data code conversion portion.

Abstract: An InP solar cell having a p-type InP single crystal substrate having a carrier concentration of 2.times.10.sup.16 -2.times.10.sup.18 cm.sup.-3, an n-type InP layer containing a dopant of at least one element selected from VIA group including S and Se disposed on said substrate with a thickness of 0.05-1 .mu.m, said n-type InP layer having a carrier concentration of 5.times.10.sup.17 -1.times.10.sup.19 cm.sup.-3, a grid electrode arranged on said n-type InP layer, and an anti-reflection coating formed on said n-type InP layer and said grid electrode. The solar cell has a high efficiency and superior radiation resistance characteristics.

Abstract: The adhesive composition or compound of the invention comprises an epoxy resin, a reactive diluent and a hardener, and at least one of said components contains fluorine atoms. The adhesive composition containing fluorine atoms, according to the invention, provides a cured or hardened composition having small refractive index due to the presence of fluorine atoms. The refractive index of the hardened product may be freely controlled within the range of n.sub.D.sup.23 =1.415 to n.sub.D.sup.23 =1.570.The adhesive composition may be applied for the production of optical members for use in a communication system utilizing optical fibers or in a variety of optical instruments, and has improved heat resistance and adhesive property and is improved in matching of the refractive index with that of the material used for the optical member, such as optical fibers or glasses having lower refractive index used in a lens system.

Abstract: A position detecting system suitable for the position control of the surface of a workpiece mounted in an electron beam exposure system is disclosed which includes an electrically-driven light source, a first optical system for focusing a light beam from the light source on a workpiece, a position-controlling table for mounting thereon the workpiece, a second optical system for focusing light reflected from the workpiece on a predetermined image surface, a photodetector having a light receiving surface arranged on the image surface, and a negative feedback amplifier for controlling the light source by the output of the photodetector.

Abstract: A method for producing a glass preform for optical fibers by heating a glass soot preform consisting of glass fine particles made mainly of silicon oxide, which method comprises the steps of:(1) heating the glass soot preform to dehydrate and to remove impurities therefrom;(2) heating the glass soot preform in a gas atmosphere containing at least fluorine or fluorine-based compound to add fluorine to the glass soot preform; and(3) heating the glass soot preform to make it transparent, from the transparent preform prepared by which method, an optical fiber having superior transmission characteristics can be prepared.

Abstract: Optical recording medium includes a substrate, a coloring agent layer formed on the substrate, a light absorber layer formed on the coloring agent layer and a developer layer formed on the light absorber layer. The coloring agent layer is separated from the developer layer by the light absorber layer and the lamination layer composed of these layers has a uniform thickness. The optical recording medium is produced by vacuum depositing a coloring agent, a light absorber and a developer successively on the substrate to form a multi-layer construction, the substrate being capable of transmitting visible light and near infrared light. Alternatively, the optical recording medium contains a plurality of lamination layers mentioned above. The optical recording medium has a high contrast and achieves a high speed multi-color recording.

Abstract: Heat-sensitive magnetic transfer element for printing magnetic image to be recognized by magnetic ink character reader (MICR), which comprises a heat-resisting foundation and a heat-sensitive transferring layer provided on the foundation, said transferring layer having a melting temperature of 50.degree. to 120.degree. C. and comprising 30 to 97% by weight of a ferromagnetic substance powder, 2 to 69% by weight of a wax and 1 to 68% by weight of a resin. The transfer element gives a printed magnetic image having high accuracy of dimensions and high magnetic properties by thermal printing method.

Abstract: A transcoder which transcodes adaptive differential pulse code modulation (ADPCM) signals to pulse code modulation (PCM) signals without cumulative transcoding noises even if mutual transcoding between ADPCM signals and non-linear PCM signals is repeatedly conducted. Two PCM signals are generated having values of one step higher and one step lower than a third PCM signal having a nominal code value. The three signals are fed to a selector, which sequentially selects one of the three. The output of the selector is then decoded and fed to one input of a subtractor, and a prediction signal is fed to the other input of the subtractor. The output of the subtractor is coded into an ADPCM signal in a step size of the input ADPCM signal. The logical value of that coded ADPCM signal is compared with the logical value of the input ADPCM signal by a comparator. A gate allows the PCM signal output from the selector to pass only when the comparator has an equal output.

Abstract: In an ultrasonic inspecting apparatus, propagation time is measured between a transmitting point of an ultrasonic wave from outer circumference of a subject material and a receiving point of the ultrasonic wave at another point on the outer circumference spaced apart from the transmitting point by a predetermined angle, and a predetermined sequence of operations is performed with the measured propagation times and the known constants, thereby internal information concerning the material, including location and shape of a defect existing therein, is provided.

Abstract: An optical head for use with an optical disk has a unit packaging an optical path conversion device for converting a light beam path from substantially in parallel to the surface of a rotating optical disk into a direction substantially perpendicular to the surface of the optical disk, a lens system for focusing the light beam onto the recording surface of the optical disk, and a focus controlling mechanism for adjusting the focus of the lens system. A head outer shell supports the unit by one or more diaphragms for movement of the unit in the parallel direction of the optical path. A track control mechanism which includes an electromagnetic actuator adjusts the positional relation of the unit relative to outer shell in that parallel direction without causing unit movement in the perpendicular direction.

Abstract: A full wave rectifier comprises an input terminal supplied with an AC signal and an output terminal for delivering a rectified DC signal. An operational amplifier having an inverting input terminal, amplifies the AC signal. A rectifier gain setting is provided by a first resistor connected between the input terminal and the inverting terminal of the amplifier. A second resistor, having the same resistance as the first resistor, is connected between the inverting terminal and output terminal of the amplifier. A depletion type MOS FET operates responsive to the output of the amplifier, for performing a switching operation.

Abstract: In a composite concentration system of the type utilizing a time division system in which voice signals are digitized and then concentrated in a traffic, there are provided a first subscriber line interface means of a first type which connects subscriber lines directly to subscriber line interface circuits, a second subscriber line interface means of a second type which connects subscriber lines to subscriber line interface circuits via a space division concentration switch and a time division concentration switch connected to the first and second subscriber line interface means via switching interfaces.

Abstract: In a speech recognition system using time-warping for better matching, accuracy and efficiency of dynamic programming computation is improved by expanding the approximated start and end points into an assembly of points, and performing successive iteration for lattice points d.sub.i,j spaced N.gtoreq.3 points apart rather than every lattice point.

Abstract: A semiconductor integrated circuit in which layers such as an field isolation region, a gate electrode, interlayer insulating films and interconnection lines are formed by the combined use of a lift-off process and an ECR plasma deposition process. According to the present invention, even if vertical dimensions of patterns of the respective layers are large as compared with their lateral dimensions, the upper surfaces of the respective layers can be planarized, permitting the fabrication of an LSI of high packing density, high operating speed and high reliability which is free from shorting and breakage of the interconnection lines.

Abstract: A semiconductor device in which a film of an insulator a conductor is closely deposited in a groove formed in a semiconductor substrate or an insulating or conductor layer thereon to planarize the surface thereof.A semiconductor device manufacturing process in which a specimen is selectively etched away through using a resist pattern as a mask, a pattern forming film is deposited by a plasma deposition technique on the specimen, and the resist film is removed, whereby the pattern forming film closed fills up a groove formed by etching to provide a planarized surface.

Abstract: In an information memory device of the type wherein informations are sequentially stored in cells of a memory cell array and read out from the cells according to selected addresses, there are provided an internal address generator for generating an internal address, an address information selector for selecting either one of the internal address and an external address supplied from outside to form a selected address, and an information memory circuit for storing a memory information at a position designated by the selected address and for reading out the information stored in the designated position.