Abstract: An optical atmospheric link apparatus transmits information data by means of a light beam, an error signal is generated representative of a difference between a direction of a light beam projected from a optical lens means and a direction of a light beam received from a remote transmitter/receiver and a position of a light path of the light beam incident into an optical lens from a light emission means is controlled on the basis of the error signal so that the direction of the light beam projected from the optical lens becomes coincident with the direction of the light beam received from the remote transmitter/receiver.
Abstract: A card having retroreflective bar codes is comprised of a card substrate on which there are provided a first information recording portion formed of a retroreflective material portion of a predetermined pattern and a second information recording portion which can be read out from a nearby place. Also, a card having retroreflective bar codes is formed of recorded tracks comprised of retroreflective material portions and nonretroreflective portions which are formed on a heat distortion material formed of a retroreflective member or retroreflective material by a selective heating and distortion process in response to information to be recorded.
Abstract: A data reproducing apparatus for reproducing main data from a disc on which a data string comprised of main data and auxiliary data appended to the main data at intervals of predetermined lengths of the main data, which main data are previously error correction coded input digital data. The main data are separated from data read from the disc and error-corrected in a decoder. The error-corrected data are stored in a memory. The data stored in the memory are continuously read by a readout control circuit. Data patterns before and after connecting portions of the main data written in or read from the memory are compared in a comparator and the next data are continuously reproduced at a time point when the data pattern coincidence is detected in the comparator.
Abstract: The present invention relates to an optical recording/reproducing apparatus that can be suitably adapted to a magneto-optical disc apparatus which records data on, for example, a magneto-optical disc or reproduces data therefrom. An auxiliary synchronizing signal (3h) is recorded at a predetermined position on a recording medium, (1) on which a synchronizing signal (2a) is periodically prerecorded in advance, by the same recording means as the recording means for recording data between the synchronizing signals (2a) and (2a) and a phase of a data read clock signal of which the phase is locked by the synchronizing signal is controlled on the basis of the auxiliary synchronizing signal (3h). Thus, data can be properly read from the recording medium (1).
Abstract: An editing apparatus for editing digital video signals employs a number of video recording and/or reproduction devices, a signal processing mechanism, and a switching mechanism, wherein the number of transfer lines and the area occupied by the associated connectors is decreased by converting parallel signals into serial format.
Abstract: An optical disc (2) equipped with a hub (5) having a centering hole into which a spindle shaft of a disc driving mechanism is inserted, wherein a centering hole portion of the hub is provided with a centering hole reinforcing material (6) excellent in abrasion resistance and smoothness or a member (14) having a central hole is formed of a resin excellent in abrasion resistance and smoothness. Reinforcing ring (6) includes a metal layer plated on the peripheral portion of the centering hole, and the metal layer is impregnated with fluoric resin.
Abstract: A disk recording and/or reproducing apparatus comprises external magnetic field generating means for applying an external magnetic field to a given area, of a rotating disk on which information signals are recorded; of a rotating disk; means for moving the external magnetic field generating means toward and away from the disk in response to commencing an operation of recording of the informational signals on the disk; and means for loading the disk on such a position where the informational signal can be recorded. The moving means moves the external magnetic field generating means toward the disk only when the loading operation of the disk by the loading means is completed. Accordingly, contact of the magnetic head with the disk while the disk is not rotated is prevented.
Abstract: A spindle servo system for a magneto-optical recording/playback apparatus, comprising a PLL circuit lockable in phase by sample servo pits formed on a track of a magneto-optical disc; a phase comparator for comparing the phase of a signal, whose period corresponds to the output of the PLL circuit, with the phase of a reference frequency signal; and a resonator having a reference frequency conforming to the eccentricity cycle of the disc. In this servo system, the rotation period of a spindle motor for driving the disc is controlled in accordance with the output of the phase comparator and the output of the resonator. The PLL circuit includes a voltage-controlled crystal oscillator, and the resonator is excited in conformity to the output of the phase comparator to control the rotation frequency of the spindle motor, thereby reducing the jitter component included in the output of the PLL circuit.
Abstract: An apparatus for recording compressed digitized information to an optical disc by reading the digital data into a memory for transient storage. The digital input data thus written into the memory are sequentially read out of the memory and into an encoder at a transfer rate faster than the input transfer rate where the digital data are arranged in discrete clusters of record units including cluster-linking groups such that each record unit can be interleaved independently and without affecting other record units. The interleaved record units are then recorded onto an optical disc. Reproduction of the record units from the optical disk is carried out by reversing the process.
Abstract: An optical communication system which does not require a re-adjusting operation of an irradiating direction of a light beam and is improved in convenience in use. The optical communication system includes first and second terminals remotely located from each other for transmitting therebetween a light beam carrying an information signal therein. A first light beam having a predetermined direction of polarization is generated in the first terminal and transmitted to the second terminal by way of an optical system while a second light beam having a different direction of polarization comes from the second terminal and is received by way of the optical system. A beam selector passes one of the first and second light beams and reflects the other light beam. An electric signal is generated in response to the received second light beam, and the direction of the first light beam is controlled in response to such electric signal.
Abstract: A spread spectrum signal receiving apparatus comprising: a radio frequency processing circuit for converting a spread spectrum signal into an intermediate frequency signal; a binary encoder for encoding the intermediate frequency signal; a pseudo-random noise code generator; a code driver for controlling the phase and the chip speed of the output of the code generator; a first multiplier for multiplying the binary signal by the output of the code generator; a numerical controlled oscillator for outputting first and second carrier signals; second and third multipliers for multiplying the output signal of the first multiplier respectively by the first and second carrier signals; first and second low-pass filters supplied with the output signals of the second and third multipliers respectively; and a microcomputer having functions to produce signals for controlling the numerical controlled oscillator, and functions to produce signals for controlling the code driver.
January 16, 1992
Date of Patent:
June 22, 1993
Katsuya Hori, Tadao Yoshida, Wataru Yamatani, Eiichiro Morinaga
Abstract: A video disc apparatus including a disc rotating device for rotating an optical video disc at a constant linear velocity, a tracking servo device for causing an optical pickup to tack a recording track on the optical video disc, and a translating device for translating the optical pickup along the radius of the optical pickup. It is detected by a detection device if the rotational frequency of the optical video disc by the disc rotating device is within a frequency range in the vicinity of the resonance frequency of the optical pickup. Depending on a detection output of the detection device the operation of an access controlling device is switched so that, in the frequency range in the vicinity of the resonance frequency of the optical pickup, a track jump control is performed for shifting the optical pickup towards the target track position on on the optical video disc with the tracking servo device in the energized state.
Abstract: A method of recording user data on a DC-RAM disc medium comprising the steps of recording servo signals in a pair of spaced apart servo areas in each one of a predetermined number of segments which form a predetermined number of sectors of each one of a plurality of recording tracks on the disc medium, and recording along a portion of each track, between each servo area, units of 12 bytes of user data and 4 bytes of parities for the user data so that among the predetermined number of segments are a plurality of user data segments each consisting of a servo signal and one or more units of 12 bytes of user data and the parities for the 12 bytes of user data.
Abstract: This invention is directed to a method comprising the steps of detecting the intensity of a return laser beam from an optical recording medium of a recording laser beam for forming pits onto the optical recording medium at the time of a recording mode to record information thereon, and controlling a power of the recording laser beam on the basis of a ratio between a detected output of the intensity of a return laser beam within a predetermined time required until pits are actually formed on the optical recording medium and a detected output of the intensity of a return laser beam within a time period during which pits are actually formed, whereby even if the relationship between the recording laser power and pits formed varies due to characteristic unevenness, skew (inclination), or temperature of the medium, etc., this method permits formation of pits in a fixed reasonable dimension to carry out an optimum information recording.
Abstract: An index displaying device for a video disk player is capable of discriminating between a command signal provided by operating the keys of a remote controller and a command signal provided by reading a bar code by the remote controller, and of omitting displaying unnecessary indices on the screen of a monitor when the command signal given thereto is produced by reading a bar code. The index displaying device comprises a signal receiver for receiving a signal transmitted by a remote controller, an index signal generating circuit that generates an index signal corresponding to the command signal received by the signal receiver to be displayed together with signals reproduced from the video disk, and a control circuit that decides if the signal received by the signal receiver is produced by reading a bar code and controls index displaying operation according to the result of the decision.
Abstract: During recording the inputted data are sequentially written into a memory at one transfer rate and are read out at a second, higher transfer rate for recording on a record medium. The reading of the memory is such that data in a preset first amount are successively read from the memory to always ensure a write space in the memory which has a capacity which is higher than a predetermined second amount when the amount of the inputted data stored in the memory exceeds the first amount. During playback, the recorded data are reproduced at a second transfer rate, which is higher than a first transfer rate required for outputting the reproduced data, and are written in the memory. The thus written data are successively read out of the memory as reproduced output data at the first transfer rate.
June 19, 1991
Date of Patent:
May 25, 1993
Yasuaki Maeda, Yuji Arataki, Tadao Yoshida
Abstract: A laser light source in which a couple of light beams whose shapes are re-formed and whose polarizing planes are made perpendicular to each other are synthesized by a beam splitter and then the synthesized light is incident on an optical guide through a predetermined optical system, thereby generating the synthesized light having a short spot diameter and an improved power density.
Abstract: A portable electronic apparatus including a casing having a connecting surface adapted to be connected to a connecting surface of an external apparatus; a control unit accommodated in the casing; a transmitting terminal provided on the connecting surface of the casing for transmitting data as an optical signal generated by the control unit; and a receiving terminal provided on the connecting surface of the casing for receiving data as an optical signal generated by the external apparatus. The transmitting terminal and the receiving terminal are positioned in symmetrical relationship to each other with respect to a center of the connecting surface of the casing. Accordingly, in carrying out data transfer by optical space communication between two portable electronic apparatuses of the same kind, the transmitting terminal of one of the portable electronic apparatuses can be easily aligned to the receiving terminal of the other portable electronic apparatus.
Abstract: A semiconductor apparatus for propagating light in a preferred direction which comprises, in succession, a substrate, a first emitter region, a first carrier confinement region, a first internal heterojunction barrier, a first base region, a second base region, a second internal heterojunction barrier, a second carrier confinement region, and a second emitter region, wherein portions of the first emitter region and the second base region are of one conductivity type and portions of the second emitter region and the first base region are of the opposite conductivity type, wherein the first and second emitter regions, the first and second internal heterojunction barriers and the first and second base regions together define a single optical cavity in the directions perpendicular to the preferred direction of light propagation, and electrodes are provided for applying an electrical current which flows through the semiconductor apparatus.
Abstract: The present invention is directed to a differential phase-shift keying (PSK) signal demodulator in which an error rate provided when a signal modulated according to a .pi./4-shift DQPSK modulation system is demodulated can be improved. The differential PSK signal demodulator of the present invention includes means for phase-shifting a phase of a detection reference axis by a predetermined angle each in the counter-clockwise direction in synchronism with a timing at which a symbol to be detected is supplied, wherein the modulated signal is synchronizing-detected such that a rotation angle of the symbol and an angle of a detection reference axis are inhibited from becoming equal to each other, thereby a zero level being prevented from being output as a demodulated output.