Showing papers by "NEC published in 1983"

InGaAsP double-channel- planar-buried-heterostructure laser diode (DC-PBH LD) with effective current confinement

Abstract: A new high-performance 1.3-μm InGaAsP semiconductor laser is described, in which effective current confinement into the active region has been realized. A p-n-p-n current blocking structure is made by liquid-phase epitaxy (LPE) on both sides of the active-stripe mesa which is defined by a pair of channels in the double-heterostructure wafer. The double-channel-planar-buried-heterostructure laser diodes (DC-PBH LD's) exhibit high-laser performances, such as a high differential quantum efficiency of 78-percent maximum, which results in high electrical to optical power conversion efficiency 43 percent, and high light output power of over 50 mW, as a result of the improvement in the current blocking structure. The threshold current temperature sensitivity is found experimentally to be reduced remarkably by increasing the doping concentration in the p-cladding layer. Characteristic temperature as high as 100 K has been obtained. CW operation is possible up to 130°C.

Color ink-jet printer

Abstract: A print mechanism includes plural print heads arranged in a horizontal direction with each print head including a plurality of nozzles arranged in a vertical direction The entire print mechanism is disposed on a carriage movable in the horizontal direction Each of the print heads is preferably supplied with a different color ink, and the printing signals used to energize the nozzles in each print head are delayed for the second and subsequent print heads by an amount corresponding to the time required for the carriage to move horizontally through the displacement between the first print head and the second and subsequent print heads

Multilayer electrostrictive element which withstands repeated application of pulses

Abstract: A multilayer electrostrictive element has electrostrictive sections (31) defined by internal electrodes (32) in a stack, with a peripheral surface which has a predetermined outline perpendicularly of an axis of the stack, each internal electrode with an outline which is approximately congruent with the predetermined outline (constant cross-section). In order that external electrodes (33, 34) may readily be connected to the internal electrodes grouped by twos, each internal electrode may have a peripheral end which is partly recessed from the predetermined outline, as in FIG. 8. Alternatively, the internal electrodes of each group may be connected together by a conductor rod which passes through the electrostrictive sections, preferably along their edges, contacting alternate electrodes. For a great number of internal electrodes, an element may be manufactured by laminating conductive-paste-printed green sheets transversely of the stack axis and then sintering the lamination. Each internal electrode may include a ceramic material, such as an electrostrictive material of the electrostrictive sections, another electrostrictive material of a lower sintering temperature, or glass.

Battery saver for a paging receiver or the like

Abstract: A battery saving circuit for use in a portable radio communication apparatus adapted to receive a communication signal which includes a preamble and identification codes. The apparatus includes a receiver section, a waveform shaper section, a decoder section and a power supply. The battery saving circuit, forming a portion of the decoder section, periodically generates a first control signal which causes the power supply to be electrically connected to the receiver and waveform shaper sections. A second control signal is generated to disconnect the receiver and waveform shaper sections from the power supply when, during an assigned time period, the preamble code is not detected. A third control signal is generated to maintain electrical connection between the power supply and the receiver and waveform shaper sections for a selected period of time after the preamble is detected.

Instruction prefetching device with prediction of a branch destination address

Abstract: An instruction prefetching device of a data processing system prefetches an instruction sequence, usually before decoding of a branch instruction being prefetched, by predicting a branch destination address which is preliminarily stored in a branch history table (46) and retrieved by an instruction address of the branch instruction. Preferably, a prediction evaluating circuit (66) evaluates the predicted destination address with attention directed to a result which is obtained by actually executing the branch instruction and indicates whether the branch instruction indicates "no go" or "go" to the branch. When the prediction is incorrect, the prefetch is suspended. Furthermore, the branch destination address is renewed to a new address obtained by decoding of the branch instruction. More preferably, a discriminator (73) discriminates whether or not the instruction being prefetched is really a branch instruction. If not, the predicted destination address is neglected.

An Automatically Controlled Predistorter for Multilevel Quadrature Amplitude Modulation

Abstract: In digital microwave transmission, the nonlinear characteristics in a high power amplifier, such as a TWT (traveling-wave tube) inhibit efficient output use. This note introduces a new predistorter control technique, and assesses the nonlinear compensation capability of a third-order predistorter incorporating this technique. Concerning 16-QAM (quadrature amplitude modulation) a 10 dB reduction in out-of-band emission and larger than 8 dB C/N improvement with respect to symbol error rate can be achieved at 3 dB TWT average output power backoff.

A memory system for storing analog information

Abstract: The non-volatile semiconductor memory elements hav­ ing an MlS structure show a hysteresis curve in the gate voltage - the threshold voltage characteristic. The con­ tinuously changing region of the hysteresis curve is used to operate the memory elements as analog memories. The input analog signal is applied to the gate electrode of a selected memory element after it is converted to have a voltage within the continuously changing region, to change the threshold voltage of the selected memory element. The changed threshold voltage is read out in read-out operation.

Solid-state image device with resin lens and resin contact layer

Abstract: In a solid-state image device comprising an image storage block having a block surface, a plurality of storage elements are embeded along the block surface to store an image in the form of electric charge An overlying layer is deposited to form an array of optical lenses in correspondence to the storage elements An intermediate layer is laid between the block surface and the overlying layer Incident light focuses through the lenses and the intermediate layer onto the storage elements The intermediate layer serves as an adjusting layer for adjusting a focal length

Data-flow-type digital processing apparatus

Abstract: A data processing apparatus having a dataflow architecture includes an addressor module, an operational module and a memory module, and data to be processed is accompanied by a command and is applied to the respective module through a uni-directional bus. The addressor module and the operational module are integrated within a common hardware circuit having a feedback loop. A normal operation (an arithmetic and logic operation) is executed by the common hardware circuit by using only the uni-directional bus, while an address generating operation is executed by the common hardware circuit by using the uni-directional bus and the feedback loop.

Production system for manufacturing semiconductor devices

Abstract: A production system for manufacturing semiconductor devices comprises apparatus for making a semiconductor wafer during a first process step. A plurality of semiconductor devices, or semiconductor chips are arranged and incorporated in the wafer. A second apparatus processes the semiconductor material in a second process step during production. An inspection apparatus provides an automatic inspection function between the first and the second process steps. The inspection result is automatically estimated by the inspection apparatus, with respect to a specification value and a central value within the specification value. The inspection apparatus is connected to a third apparatus for carrying out at least one further manufacturing step after the second process step. Accordingly, if the estimate of the inspection apparatus is within the specification value, but out of adjustment with respect to the central value. An instruction signal can be automatically sent to either the second or the third manufacturing apparatus, to compensate in the direction of the central value.

Internal electrode piezoelectric ceramic actuator

Abstract: A piezoelectric ceramic actuator element with multilayer internal electrodes has been investigated. It was fabricated by multilayer ceramic capacitor techniques. An individual internal electrode has the same area as the element cross section area. It has no piezoelectric inactive part, so that it shows original strain/field characteristics in the material. It can be driven by a relatively low votlage (< 200V) and has a semi-permanent life under successive voltage pulse application. Typical properties of the element using 0·65Pb(Mg1/3Nb2/3)O3-0·35PbTiO3 ceramics are 8·7 × 10−4 strain, over 3·5 × 107 N/m2 force, within 100 μsec response time and 70% electromechanical couplig factor driven by 1 × 106 V/m field.

Efficient backward and forward pumping CW Raman amplification for InGaAsP laser light in silica fibres

Abstract: By pumping a small-core single-mode silica fibre with a 1.32 μm CW Nd:YAG laser, continuous-wave Raman amplification of InGaAsP laser diode light, with unsaturated gain as high as 21 dB, has been obtained in both backward as well as forward pumping configurations.

Method and device for matching fingerprints with precise minutia pairs selected from coarse pairs

Abstract: A pair candidate list (73) is formed by selecting minutia pairs with reference to a minutia list (71) showing original position and direction data given for minutiae by principal coordinate systems preliminarily selected on a search and a file fingerprint and those relation data of the minutiae which are substantially independent of the coordinate systems. It is very likely that the pair candidate list shows coarse pairs because the coordinate systems may not yet be optimally matched to each other. One of the coordinate systems is transformed by those optimum amounts to provide transformed position and direction data which are decided by the original position and direction data of the minutia pairs of the pair candidate list. A pair list (86) is formed by precisely selecting minutiae from the pair candidate list with reference to the transformed position and direction data and the original position and direction data given by the other principal coordinate system and to the relation data. On forming the pair list, an additional minutia list (81) is preferably formed which shows the transformed position and direction data and the last-mentioned original position and direction data together with the relation data.

Low Firing Temperature Multilayer Glass-Ceramic Substrate

Abstract: A glass-ceramic material, which has a low constant (7.5) and can be sintered at 900°C in air or in a neutral atmosphere, has been found. As a result, it has become possible to prepare a multilayer glass-ceramic substrate which is advantageous for decreasing propa- gation delay. The new multilayer glass-ceramic (MGC) substrate has the following excellent characteristics. 1) Gold and silver-palladium alloys can be used in fabricating wirings or circuit patterns. 2) The new MGC substrate has a high flexural strength of 3000 kg/cm2 (43000 Ib/in2). 3) During the firing process, shrinkage is around 12.5 percent and shrinkage tolerance is extremely small (0.3 percent or less). 4) The thermal expansion coefficient is about 42 x 10 -7 deg -1 (from room temperature to 250°C) and is close to that for silicon semicon- ductor chips. The MGC substrate was experimentally produced and used in multilayer substrates for a multichip package computer sys- tem. It is possible to form via holes easily with 100 pm diameter and to use loo-pm linewidth on a 200~pm line-to-line grid. A green sheet (120 mm square) may have as many as 110 000 via holes punched into it. It has become possible to provide a high-density packaging substrate using this method.

Corrosion-resisting Co-Pt thin film medium for high density recording

Abstract: This paper describes a new material medium for high density longitudinal recording. Sputtered Co-Pt thin films will be shown to have excellent corrosion resistance and magnetic properties. Co-Pt thin films do not need a thick overcoat like plated Co-Ni-P films do, and have higher remanent flux density than ferrite thin films. Co 1-x Pt x (X=0-0.60) thin films prepared by r.f. diode sputtering have a maximum Hc value near X=20. The Hc, Bs and squareness, for 20 at.% Pt film are 1,100 Oe, 12,000 G and 0.80-0.90, respectively, at 0.1 μm film thickness. These values are not changed over 1-15 Watt/cm2power densities, corresponding to 6-85nm/min deposition rates. Films with more than 28 at.% Pt have no Bs change after immersion in water for over one month, indicating that the films are passive by this test, at least. Ni additions improve magnetic and corrosion properties. There is no Bs change for Co 0.070 Ni 0.010 Pt 0.020 films after immersion in water for over one month. Finally, 51 KFRPI linear recording density was obtained, at D 50 , using a Co 0.70 Ni 0.10 Pt 0.20 thin film disc with a 0.46 μm gap length head and a 0.12 μm head-medium spacing.

Data communication device including circuitry responsive to an overflow of an input packet buffer for causing a collision

Abstract: A data communication device for use either as an interface between a data processing device and a transmission medium of a CSMA/CD network or as a repeater between a CSMA/CD network and an additional data communication network which shares a transmission medium with the CSMA/CD network, sends an obstruction signal towards the CSMA/CD network when an input buffer tends to overflow on storing an input data packet for delivery to the data processing device or for transmission towards the additional data communication network. The obstruction signal is for causing a collision in the CSMA/CD network. The additional data communication network may be plural in number. When the additional data communication networks are CSMA/CD networks, the transmission of data packets thereto is suspended when a collision is detected at the repeater. The transmission is restarted a variable interval after disappearance of the collision. The variable interval corresponds to a weighted random number known in the art.

Digital image processing by hardware using cubic convolution interpolation

Abstract: Disclosed is hardware for providing pixel data by interpolation. In the hardware previously memorized weight factors corresponding to the particular site are retrieved under the influence of the outputs of addressing circuits, multiplied with the original pixel data corresponding to the site prior to convolution and the products added together to derive the new pixel data which is subsequently stored in a memory. Also disclosed is hardware for rapidly enlarging an image. In this hardware, four lines, for example, of original pixel data are read out and, according to the degree of enlargement required, a predetermined sequence of weight factors are simultaneously applied to sixteen original pixel data (four from each line) to determine the data for the site or sites in question.

A Preparation of Perpendicular Magnetic Recording Media by an Electroless Plating Method

Abstract: The perpendicularly oriented crystal structure conditions of electroless plated film for high density perpendicular recording media were investigated mainly by (002) plane rocking curves and cross sectional SEM observation. A highly oriented narrow dispersion of c‐axis orientation normal to the surface plane was consequently obtained, and the columnar structure of hcp crystal with ca. 0.05 μm diam was confirmed. As a result of preparing disks A and B, which were chemically plated from an optimum bath and a more improved bath, respectively, the recording characteristics with a combination of ring head were obtained as recording densities of for disk A and 25,000 FRPI for disk B, in spite of a relatively thick magnetic medium. The di‐pulse waveforms, which are characterized with perpendicular recording, were observed at low bit recording density. It was indicated by the above results that the chemically plated Co alloy films are applicable as a perpendicular recording medium.

A semiconductor device having a container sealed with a solder of low melting point

Abstract: A semiconductor device forming a hermetically sealed housing for a semiconductor element, comprising a base member, a wall member surrounding the semiconductor element, and a cover hermetically sealed to the wall member. According to the invention, an intermediate annular member (17) is interposed-between the cover (11) and wall member (12'), the intermediate member being attached to the cover by a solder glass (16) and exhibiting a metal surface facing the wall member for being attached to the wall member by metallic solder. A protrusion (15) of the wall member (12') fully or partly surrounds the intermediate member (17) and is also attached thereto by metallic solder. This structure enables the manufacture of a perfectly sealed housing without applying excessive heat to the assembled device which may damage the semiconductor element.

A high photosensitive IL-CCD image sensor with monolithic resin lens array

Abstract: A high photosensitivity interline transfer CCD image sensor with monolithic resin lens array was developed. The resin lens array was made on the 2/3 inch scheme 768(H) × 490(V) pixels interline CCD image sensor by using the resin thermal flow technique. The resin lens array consists of a smooth base resin layer and overlaid vertical stripe semicylindrical lens array corresponding to photodiode vertical lines. The effective photodiode aperture, which was only 40% for the original device, was increased to 80% for the device with monolithic resin lens array. The photosensitivty reached 0.18 µA/µW at 550 nm, which corresponds to 0.4 quantum efficiency.

Multiple access system and method

Abstract: In a multiple access system for performing packet communication involving sharing of a single communication medium by a plurality of users, the single communication medium is divided into a plurality of channels. Each user monitors the condition of each channel, and probability of packet transmission to each channel is controlled in accordance with a monitored result.

Device for giving a pattern a rotation of an integral multiple of 90° with the pattern read from a memory on a block by block basis

Abstract: An original pattern stored in a first memory, is read out in read-out blocks. A rotated pattern, namely, the original pattern given a rotation of one of 0°, 90°, 180°, and 270° that is selected by a selection signal, is written in a second memory in write-in blocks. Each of the read-out and write-in blocks consists preferably of N N-bit words, where N represents a predetermined integer. The write-in block in which a read-out block should be written with the rotation, is selected by the selection signal. Each read-out block is stored in an array of shift registers for the respective words of the block and successively read out stage by stage into a loading circuit for the second memory as words of one of the write-in blocks when the rotation is 90° or 270°. Words of each read-out block may directly be transferred to the loading circuit when the rotation is 0° or 180°. The loading circuit is controlled by the selection signal on loading the second memory with each word of the write-in block. The second memory may be the memory used as the first memory. In this case, a buffer memory should be used in temporarily keeping the read-out block in which one of the write-in blocks should be written. The buffer memory is preferably another shift register array which is alternatingly used in combination with the first-mentioned shift register array.

Adaptive predictive coding apparatus of television signal

Abstract: In an adaptive predictive coding apparatus for coding an input television signal so as to perform predictive coding by determining an optimum prediction function among a plurality of prediction functions for each of a plurality of blocks obtained by dividing up a frame of the input television signal, each of the blocks having a plurality of picture elements, and to perform selection of quantizing characteristic and coding control such as subline and subsample coding, data necessary for representing a given prediction function of the plurality of prediction functions and data necessary for representing a prediction error amount per the block for the given prediction function are evaluated. Sums of evaluated data are compared to produce, on a block by block basis, one of the prediction functions which provides a minimal sum as an optimum prediction function.

Software Quality Improvement

Abstract: Similarly, \"superior communication\" in the manmachine interface refers to an approximation of human communication. Users want software that allows input and otput in less esoteric formats. The operator should have to descend to the level of the machine and Agage in dialog at each and every step. Voice I/O and dati processing in natural languages are sterling examples of superior communication. The rapid growth of software

Semiconductor device provided with a package for a semiconductor element having a plurality of electrodes to be applied with substantially same voltage

Abstract: The present invention relates to a semiconductor device including a package for carrying a semiconductor element or chip having a plurality of components, such as transistors, diodes, etc. to which substantially the same voltage is to be applied. The voltage may be supplied to a plurality of electrodes distributed on the semicnductor element. Excessive voltage drop between the components and external leads of the device is inhibited by providing a package with at least one low resistance conductive layer about the periphery of the device which is electrically connected to an external lead of the device and to a plurality of electrodes on the semiconductor element.

Optical switch of switched directional coupler type

Abstract: An optical switch with switched optical directional couplers, switched by the application of either 0 volt or a voltage V 1 , different from 0 volt. Coupling of almost 100% is achieved when the V 1 voltage is applied to a selected directional coupler, while coupling of 0% to 20% occurs when 0 volt is applied to the selected directional coupler. The optical directional coupler is formed by locating adjacent optical waveguides in close proximity and applying electric field producing electrodes to the waveguides where they are in close proximity such that the substrate below opposing waveguide sections receive electric fields of opposite directions.

Logic simulator operable on level basis and on logic block basis on each level

Abstract: A logic device, which may be a digital computer, is simulated by dividing the device into logic blocks and classifying the blocks by levels according to flow of signals in the device. A state memory simulates input and output logic states of the respective blocks. A simulator simulates operations of the respective blocks. The blocks on each level are successively simulated in four stages, namely, (1) provision of simulated logic states for the respective output logic states, (2) comparison of the simulated logic states with the respective output logic states, (3) decision of those of the input logic states of higher level blocks which should be changed into the simulated logic states, and (4) renewal of the output logic states and of the decided input logic states in the state memory. Renewal of the output logic states may be carried out during the stage (1). Alternatively, the logic blocks on each level are divided into groups with simulation for the blocks on each level substantially simultaneously carried out by a plurality of logic simulators which are assigned to the respective groups and are connected together for transfer of data and for renewal of the decided input logic states by the transferred data.

X-band self-aligned gate enhancement-mode InP MISFET's

Abstract: Self-aligned gate enhancement-mode InP/SiO 2 MISFET's with ∼0.8-µm channel length were successfully fabricated on an Fe-doped semi-insulating substrate. The fabricated MISFET's exhibited very high transconductance, as high as 200 mS/mm, and good X -band operation, especially marked high-power-output characteristics. The minimum noise figure at 4 GHz was 1.87 dB with 10.0-dB associated gain. 1.17 W/mm and 1.0 W/mm power outputs were obtained at 6.5 and 11.5 GHz, respectively. 43.5-percent maximum power-added efficiency was attained at 6.5 GHz.

Radio paging method of arranging message information with reference to a key code and a base station and a pager receiver for use in the method

Abstract: In a radio paging method of transmitting message information from a subscriber's substation (32) through a base station (30) to pager receivers (31) in the form of a radio calling signal, the message information is divided into a plurality of species to which key codes are assigned, respectively. When a selected one of the key codes is indicated from the substation prior to transmission of the message information, the base station sends a request to the substation in compliance with the selected key code to receive, as the message information, a message indicated by the request. The indicated message preceded by the selected key code is carried from the base station to the pager receivers by the radio calling signal. Each pager receiver reproduces the indicated message with reference to the selected key code. The substation comprises a push-button telephone set to send each message to the base station. Preferably, an audio response unit (46) is included in the base station to send the request by the use of an audio signal. It is also preferred that the radio calling signal should comprise call number signals of a low bit rate for calling selected ones of the pager receiver with the message information transmitted in the radio calling signal either at a high bit rate or at a plurality of high bit rates.

Development apparatus of latent electrostatic images

Abstract: An electrostatic recording system having a drum 1 carrying a positively charged latent image 14, and a negatively charged cylindrical sleeve 10 having depressions 10a or other ink holding means on its outer surface. The sleeve is rotated into a tank 11 holding an electrically conducting ink 12 which is picked up in the depressions. The sleeve and drum are counter-rotating at different velocities and approach a narrow gap at which point the negatively charged ink is attracted to the positively charged image. Thereafter the inked image is transferred to a sheet of paper and the drum is cleaned and discharged.