Abstract: The track of a videodisk is followed by a reading light beam produced by a device comprising a reading head fixed on a carriage which forms part of the moving system of a videodisk reader-recorder and is capable of radial displacement along the disk. An objective support frame is capable of displacement in a vertical direction with respect to the carriage in order to maintain focusing of the reading beam and of rotational displacement with respect to the carriage about a transverse axis at right angles to the radial and vertical axes in order to maintain the light beam on the track-following path. Flat coils located vertically in a plane parallel to the carriage path and placed within air-gaps of magnetic circuits serve to develop vertical forces which lift the reading head and initiate the vertical and rotational displacements by means of a differential supply circuit.

Abstract: An optical system for recording information on or retrieving information from a rotating disc is disclosed herein. In this system a beam of light located on one side of the disc is directed onto and laterally across a given track of the disc. The track serves to contain the recorded information and, ignoring this information, is characterized by a predetermined light transmissivity curve in its cross-direction. An arrangement for maintaining the beam and given track in a fixed lateral position relative to one another as the disc rotates, even if the track moves laterally to a limited extent from its intended path of movement, is also disclosed herein.

Abstract: A capacitance detection type stylus is attached to the free end of a cantilever which is supported on a vertically movable resilient pivot. A permanent magnet is fixed to the movable pivot. A servo-control coil is provided adjacent the permanent magnet to move it in response to angular displacement of the cantilever from a predetermined position. The pivot is moved in the direction of fluctuation of a disc record to maintain the stylus in a proper orientation with respect to the record surface.

Abstract: A tracking control system used in video reproducing apparatus to keep the signal head on the parallel recorded tracks in spite of speed deviations of the recording medium has a bi-morph leaf to support the head. The bi-morph leaf includes piezo-electric material to which a control voltage can be applied to deform the piezo-electric material to the extent necessary to deflect the leaf in the proper direction and to the proper extent necessary to keep the head mounted on the leaf alignment with the correct track section. When the leaf reaches its maximum permissible deflection, the control voltage is reversed to shift the head in the opposite direction. In so doing the head either skips a track section, if the recording medium is moving too fast, or repeats playback of a section, if the medium is moving too slowly.

Abstract: An optical information playback apparatus comprises a light detector having a light receiving area divided into four sections by transverse axes and an optical system having a cylindrical lens arranged with its axis taken at about a 45.degree. angle to a direction of an information track of an optical disk to direct a reflected light from the optical disk to the light detector. A difference signal between outputs from the light receiving sections on the opposite sides of the axis parallel to an information track of the optical disk and the axis transverse to the information track, respectively, is produced for use as a focusing signal and as a tracking signal for tracking the information track with the tracking signal having an improved S/N ratio.

Abstract: In an engraving machine a scanning head on the carriage is positioned adjacent a reader drum, and an opposite cutter head is positioned adjacent an engraving drum. The scanning head is movable sideways so that test runs may be conducted along the side of a plate mounted on the engraving drum. The engraving drum and the scanning drum have clamps to hold a photograph and the engraving plate. As the scanning head senses a particular shade of the photograph or article being copied, the cutting head is moved toward the engraving drum to engrave the plate on the drum to a particular degree. Both drums rotate together, and the carriage is intermittently stepped along the drums by the lead screw. Two ground parallel bars support a carriage on three Nylatron sliders, each of which has three Nylatron shoes. A lead screw operated by a DC motor is connected to the carriage by centrally mounted split half nuts.

Abstract: A video tape recording/reproducing apparatus for reproducing video signals recorded in successive parallel tracks on a magnetic tape includes a magnetic head for scanning the tracks to reproduce signals recorded therein; a bi-morph leaf for deflecting the head in a direction transverse to the direction along the tracks; a synchronizing signal forming circuit for producing substitute vertical synchronizing signals having correct vertical phase continuity for any of different reproducing modes, regardless of any phase discontinuity in the reproduced vertical synchronizing signals included with the video signals, the substitute vertical synchronizing signals being produced in response to either the reproduced vertical synchronizing signals or a speed ratio signal corresponding to the ratio of the speed of advancement of the tape in the reproducing mode to that in the recording mode, with the speed ratio signal being produced in response to the reproduced horizontal synchronizing signals included with the video s

Abstract: A recording system records a television video signal of 60 fields per second converted from a signal of the picture image content of a cinematographic film for projection at 24 film frames per second, in a manner such that the video signal has parts in each of which the picture image content of one and the same film frame continues during at least 4 fields thereof, along a spiral track on a rotating recording medium rotating at a rotational speed of 900 revolutions per second at a recording rate of 4 fields per revolution of the recording medium.

Abstract: A video camera for use in combination with a video recorder and having an automatic focusing device for automatically focusing a picture-taking lens to an object, trigger means to be manually actuated from outside, and a recorder trigger circuit means receiving a signal indicating the completion of focusing of the lens supplied from the automatic focusing device and a signal indicating the actuation of the trigger means and adapted to release a recording start signal to the video recorder in response to the actuation of the trigger means and to the completion of the focusing of the picture-taking lens.

Abstract: A laser recording device adapted for use in a facsimile system in which a semiconductor laser is activated by a series of pulses the number of which is produced in accordance with an input signal. The input signal is sampled with a sampling pulse signal whereas the pulses applied to the semiconductor laser are produced at a frequency which is at least two orders of magnitude greater than the frequency of the pulses used to sample the input signal. The input signal is digitized and used to address a read-only memory which outputs a number of pulses in dependence upon the amplitude of the input signal. The output number of pulses may be logarithmically related to the magnitude of the input signal.

Abstract: An editing system employing a video tape recorder (VTR) of this type in which a rotary magnetic video head is attached to a bi-morph leaf or the like so that the VTR can perform in any one of a plurality of special reproducing modes such as a slow motion mode, fast motion mode or the like without the generation of any guard band noise includes a helical scan VTR, which is adapted to carry out the special reproduction modes and is used for reproducing video signals from an original tape, the helical scan video tape recorder including a time code reader for reading out time code signals recorded on the original tape, a reference time generator, which may be another VTR, for generating a reference time code, a memory for storing certain of the time code signals corresponding to an in-point of the original tape (that is, a starting point for playing information signals recorded on the video tape), a VTR controller for setting the direction and speed of travel of the video tape at the in-point, and a central proce

Abstract: An image represented by an array of digitally valued picture elements is selectively reduced or expanded in size by the extraction or insertion of spaced apart rows and lines of picture elements, at positions which are the closest approximation to the newly scaled base, whether smaller or larger. In reproducing a given image, for example, the image may be concurrently or successively scanned by an array of photo detector elements and a plurality of digitally valued picture elements corresponding to grey scale values across the image, and distributed with a given resolution, may be generated. These values may be processed in real time, or stored in a comparable array for subsequent processing. In either event, the number of rows and lines in the array are modified in accordance with the desired scale factor, and these discrete changes are introduced at the closest approximation to optimum positions.

Abstract: A recording format is provided for video record and/or replay systems, which improves the operating performance and facilitates the implementation of many replay features. In this format, each raster of information is divided into at least two interleaved checkerboard pixel patterns and the pixels for each checkerboard pattern are recorded together and segregated from the pixels for the other checkerboard patterns.

Abstract: Apparatus is provided for use in a digital video signal playback device of the type having a record medium in which plural channels of digital video signals are recorded in a like plurality of tracks. Plural transducers, such as playback heads, are associated with respective ones of the channels and reproduce the digital video signals from the plural tracks, each transducer normally reproducing a respective, predetermined channel of the digital video signals. A detector detects the particular channel with which the digital video signal reproduced by each transducer is associated. A signal interchanger is provided with plural channel outputs and is responsive to the detector for directing digital video signals which have been reproduced by transducers associated with channels which differ from the channels of the reproduced digital video signals to the proper channel outputs as determined by the detector.

Abstract: A video disc has first and second information tracks adjacently formed thereon, and first and second FM signals with different frequency bands are recorded on the first and second information tracks, respectively. A common stylus simultaneously traces the first and second information tracks, and a signal detector circuit coupled with the stylus detects the first and second FM signals. The first and second FM signals are separated by first and second filter circuits, and applied respectively to first and second rectifying circuits, where DC voltage signals corresponding to the carrier levels of the detected first and second FM signals are produced. These DC voltage signals are compared by a voltage comparator circuit to control a tracking compensating device. Demodulator circuits to demodulate the information signals recorded on the first and second information tracks are connected to the first and second filter circuits.

Abstract: In a disc reading device wherein the rotating speed is normally controlled by detecting the synchronizing signal part of a reproduced signal, a second speed control circuit is included for measuring the speed of the disc and controlling the speed to a desired value independently of the detected synchronizing signals. When signal drop-out or the like occurs, the second speed control circuit takes over.

Abstract: A time base corrector (TBC) for a special-motion video reproduction system employing a helical-scan VTR generates write-in address data synchronized to the reproduced digital data and stores the digital data in a digital memory in accordance with the generated write-in address. When the reproducing head jumps vertically, i.e. perpendicular to the data track, the currently-generated write-in address is latched. In response to a reference signal, the latched data is transferred to a read-out address counter for generating a read-out line address, and the stored video signal is then read out of the digital memory under control of the read-out address data.

Abstract: Whether for the recording of parallel or serially occurring information, the general concept of the invention is to record sample (or bit) data in the form of damped ringing signals (e.g. of the form (sin x)/x) and to provide relative delay between the recordings of adjacent tracks so that the principal peak of one recorded signal falls on a zero crossing of another, and vice versa. Since the peaks of no two adjacent signals occur--in the case, for example, of magnetic tape--at the same longitudinal position of the tape, isolation between the signals--as recorded on the tape--is effected. By suitably sampling the signals on the tape during playback, the original signal may be reproduced.

Abstract: An MC type phono cartridge which is simple in construction and easy to assemble and in which the stylus tip may be easily interchanged. The cartridge includes a pair of magnet units and an associated vibration unit. Included in the vibration unit is a cantilever with a stylus tip fixed to one end thereof with a disc-like member fixed to the other end of the cantilever. A string is attached at one end to the cantilever and at the other end to a string member holder which is in turn attached to the supporting member. A damper is disposed between a disc-like member and the supporting member. A pair of induction coils are disposed on the disc-like member. Each of the two magnet units includes a pair of adjacent magnets disposed with like magnetic poles confronting each other with the confronting portions of the magnets spaced from the induction coil at a preset gap. The vibration unit is detachable from the magnet unit for ease of stylus tip interchange.

Abstract: An improved overcoated optical recording medium comprises a light absorptive layer and an overcoat overlying the absorptive layer wherein the overcoat has a plurality of indentations in the surface which contacts the absorptive layer thereby forming a first region of the recording medium wherein the overcoat layer does not contact the absorptive layer and a second region wherein the overcoat layer does contact the absorptive layer. The recording sensitivity in the first region is greater since the heat loss to the overcoat layer in these regions is reduced and the mechanical constraints on the formation of deformations in the absorptive layer are relaxed. The invention also includes an improved information record having information recorded in a portion of the first region as a change in the local optical properties.