Abstract: A focus servo control system for automatically adjusting a relative distance between an objective lens unit and a recording surface of an optical recording medium in which a laser light beam is converged through an object lens on a recording surface of a recording medium and the laser light is modulated by an optical pattern on the recording surface and reflected therefrom and converted into an electrical signal wherein the focus control system includes a component adapted to be energized by an electrical current to shift the object lens perpendicularly to the recording surface, a component for detecting the laser light reflected from the recording surface for producing an error signal which represents the deviation of the focus of the lens from a desired position with respect to the recording surface, and a servo amplifier adapted to amplify the error signal thereby to produce the electric current for energizing the lens shifting components, and in order to avoid wasteful electrical power consumption and the

Abstract: A high-resolution, electronic camera with real-time storage capability. The image at the focal plane of a lens (5) is electronically scanned in one direction by a linear photodiode array (1), and in the orthogonal direction by a carriage (3), motor (17), and leadscrew (13) subassembly which mechanically moves the array with respect to the lens. The motion of the array is directly translated into comparable relative motion of a recording head (19) with respect to a recording media (21) so that scanned pixel information is recorded on the media (21) concurrently with its generation.

Abstract: High information density retrieval method and system which employ the scanning of an optical disk, having a thermally-deformable record layer overlying a reflective support, with a read light beam. The optical disk tracks contain information in the form of variable-width, approximately 0.5.pi. phase-depth, pit regions interleaved between nominal thickness land regions. The pits have varying track lengths within a pit-length range constituting a disk fractional band-width of greater than 4.0 and read light reflected from the tracks is split-detected. The split-detected, electrical analog signal is peak-detected to reconstruct recorded digital data on the disk.

Abstract: A pulse interference detector is disclosed for use in a capacitance electronic disc player (CED). A relatively short-duration, high-amplitude periodic interference pulse, such as a radar pulse, is detected. The video carrier signal of the CED has a first envelope aberration in the form of a relatively long peak-to-peak duration amplitude modulation component, and a second envelope aberration in the form of the interference pulse. The CED incudes a defect corrector for inserting, when triggered, preceding unblemished display line information into a current display line void. The pulse interference detector receives and processes the video carrier signal and also detects the interfering radar pulse. The detector comprises a first signal path responsive only to the amplitude modulation component, and includes a resistor-capacitor network for producing a reference component substantially representing an average of the envelope excursion of the component.

Abstract: A control circuit causes a reproducing transducer feeding motor to move the transducer radially across a disc having a video signal recorded thereon. The video signal is recorded along a spiral track, together with first, second, and third reference signals which control the transducer tracking. A feed pulse forming circuit forms a number of feed pulses according to the number of switching pulses which are generated due to the reproduction of the third reference signal. A number of kick pulses are required for shifting the reproducing transducer element from one track turn to another track turn as it moves toward a center of the rotary recording medium, with the movement occurring at a position where the third reference signal is recorded. The control circuit causes a rotation of the motor for moving the reproducing transducer along the radial direction of the disc, according to the number of feed pulses that are obtained from the feed pulse forming circuit.

Abstract: A digital laser platemaker for imaging an electrophotographic member by electrostatic techniques using information which is derived from a source of binary data. The binary data may be achieved by scanning a pattern or may be synthesized electrically to represent that which it is desired to reproduce on the electrophotographic member. The binary data is applied to a pixel generator which is constructed and arranged to produce an output in the form of signals for driving an acusto-optic deflector that in turn deflects a laser beam to form a composite of rays. The composite of rays represent the columns of a pattern to be applied to each pixel which is generated, the rows of the pixel being represented by the output of a shaft encoder that is synchronized with the rotation of a cylinder carrying the electrophotographic member. The pixel generator produces hexagonal pixels and the pattern in each pixel represents density information derived from the binary data originally received by the pixel generator.

Abstract: A light beam emitted from a laser light source is made incident upon a video disc by means of an objective lens and a light flux reflected by the disc is made incident upon a light detector arranged in a far field of an information track of the disc. The light detector includes four light receiving regions divided in a track direction and a direction perpendicular to the track direction. A first sum of output signals from diagonally aligned two light receiving regions and a second sum of the remaining two light receiving regions are derived and then a sum signal and a difference signal of the first and second sums are formed. The difference signals are sampled by sampling pulses generated at positive going and/or negative going zero cross points of the sum signal to generate sampled values. A tracking error signal is obtained from sampled values.

Abstract: An automatic record disc playing apparatus comprises a tone arm having a connection part onto which a normal head shell having a plurality of terminals for transmitting signals which are picked up by a pickup cartridge and a head shell for automatic music piece selection play are selectively mounted, a circuit for producing a play mode changeover signal according to whether the normal head shell or the head shell for automatic music piece selection play is mounted onto the tone arm, and a circuit for urging the tone arm to perform an automatic music piece selection play operation and a normal play operation according to the play mode changeover signal produced by the circuit for producing the play mode changeover signal. The head shell for automatic music piece selection play has a detection part for detecting the sound groove portions, and the land portions between adjacent music pieces.

Abstract: An improved method and apparatus for recording and playing back a video signal on a video disc, such that selected video frames can be played back in a stop-motion fashion, with accompanying audio. Each stop-motion video frame is recorded on a single recording track on the disc, and an associated digitized stop-motion audio signal is combined with a continuous-play video signal and recorded on a plurality of preceding tracks. During playback, the tracks recording the continuous-play video signal are first scanned, to recover and display the continuous-play video frames, and to recover and enter into a memory the digitized stop-motion audio signal. The track recording the corresponding stop-motion video signal is then scanned, in a repeated fashion, to provide a stop-motion display of the video frame, while the stop-motion audio signal is extracted from the memory and converted back to its original analog format, for playback along with the stop-motion video frame.

Abstract: The invention is a matrixing system, involving optical fibers, for accessing data encoded on an optical disk. Illustratively, a plurality of first fiber bundles couples optical sources to disk locations along angular coordinates, and a plurality of second fiber bundles couples disk locations along radial coordinates to optical detectors. Selective activation of a particular source and particular detector enables a predetermined disk location to be read. The system is characterized by a random access time on the order of 100 .mu.s or less.

Abstract: A signal pickup cartridge is formed in two sections to facilitate assembly of a leaf spring to a stylus therein. The two sections are dimensioned to permit suspension of the stylus to the first section but protruding therefrom and connection of one end of the leaf spring to the second section with the second end of the leaf spring also protruding therefrom. The leaf spring is connected to the stylus after which the two cartridge sections are joined to form a contiguous enclosure to house the stylus assembly.

Abstract: A rotary recording medium reproducing apparatus comprises a rotary recording medium in which an information signal is recorded as variations in electrostatic capacitance, wherein the rotary recording medium is rotated, a reproducing stylus for making contact with and relatively scanning over the recording surface of the rotary recording medium upon reproduction, having an electrode for detecting the information signal as variations in electrostatic capacitance, a reference potential part functioning as a reference potential point, a first direct-current connection path for connecting the rotary recording medium with the reference potential part for direct-current, and a second direct-current connection path for connecting the reproducing stylus with the reference potential part for direct-current. The second direct-current connection path including a signal pickup circuit.

Abstract: An apparatus and method for recording optically an information signal on a disk-like record medium as a spiral track or concentrical tracks by modulating a main beam by the information signal to be recorded and projecting the modulated main beam onto the record medium. In order to obtain a tracking error signal, a sub beam is also projected on the record medium at an edge of an adjacent track which has been previously recorded and the sub beam reflected by the record medium is detected by a light detector to produce the tracking error signal which is then supplied to a high pass filter to remove a low frequency component from the tracking error signal.

Abstract: A stylus, having a conductive electrode, is arranged to follow a spiral groove on a disc in a video disc player. Video and audio information are recorded in the bottom of the groove as relief variations. When relative motion is established between the stylus and the groove, the spacing between the stylus electrode and relief variations provide capacitance variations representative of the recorded video and audio. A dual-gate field-effect transistor is used in a pickup circuit to detect signals related to these capacitance variations. One gate of the transistor is coupled to the stylus electrode to detect capacitance variations while the other gate is coupled to a local oscillator to modulate the detected capacitance variations.

Abstract: An improved method and apparatus for recording and playing back a video signal on a video disc, such that selected video frames can be played back in a stop-motion fashion, with accompanying audio. Each stop-motion video frame is recorded on a single recording track on the disc, and an associated digitized stop-motion audio signal is combined with a continuous-play video signal and recorded on a plurality of preceding tracks. During playback, the tracks recording the continuous-play video signal are first scanned, to recover and display the continuous-play video frames, and to recover and enter into a memory the digitized stop-motion audio signal. The track recording the corresponding stop-motion video signal is then scanned, in a repeated fashion, to provide a stop-motion display of the video frame, while the stop-motion audio signal is extracted from the memory and converted back to its original analog format, for playback along with the stop-motion video frame.

Abstract: An improved method of optically writing and/or reading high density involves: (1) predeterminedly positioning a flat, uniformly thick, flexible, optical disc with respect to an axis of rotation; (2) rotating the disc on such axis at a high speed and in a predeterminedly spaced relation to a predeterminedly shaped, smooth, featureless reference surface and (3) coupling a central region between the disc and reference surface to an ambient gas source. Related apparatus and disc configurations, including embodiments having flexible disc covers, also are disclosed.

Abstract: In a video recorder, a loading mechanism for loading a recording medium in relation to a recording head, and a control mechanism for adjustment of an optical system of an associated video camera, are arranged to be selectively operated in response to the driving force of a common driving motor.

Abstract: Slow-motion reproducing system is applied to an apparatus for reproducing video signals from a rotary recording medium on which the video signals of a plurality of fields each are recorded along a spiral track for every interval corresponding to one revolution of the medium.

Abstract: A small-sized video or audio reading pickup device in which a light beam generator generates a light beam directed to a focussing device which focuses the light beam into a beam spot on an information carrier. The focussing device is mounted on an upper portion of a cylindrical hollow support disposed in a resiliently supported frame and a beam deflecting mirror is fixedly mounted within the cylindrical hollow support and independently thereof in vertical alignment with the focussing device. A light beam generated by the beam generating device is laterally directed to and deflected off the deflecting mirror and focused via the focussing device onto the information carrier, with the vertical positioning of the cylindrical hollow support being controlled to control the size of the beam spot. Lateral positioning of the light beam on the carrier is also controlled by lateral translation of the frame, and a photo-sensitive detector is arranged to detect light beam intensity reflected from the carrier.

Abstract: The invention is an improved optical recording medium and a method for making same in which the substrate has a raised center and peripheral portions. The sides of the raised portions and the upper surface of a light absorptive layer, which overlies the unraised portion, form a mold which is filled with the overcoat material.