Abstract: In a system for playing back prerecorded information from a disc record by a groove-engaging signal pickup, an overhead signal pickup drive apparatus is provided. A support housing is reciprocably mounted in the cover of the player for movement radially of the disc record. A pickup arm, carrying the signal pickup at one end, is pivotally mounted in the support housing at its other end. Means ae mounted in the cover for driving, during playback, the support housing radially with respect to the disc record independent of the radial motion of the groove-engaged signal pickup due to the spiral groove in a manner that maintains the axis of the pickup arm substantially tangential to the groove at the point of pickup record engagement. A grounding apparatus also mounted in the cover is provided for grounding a disc record having a coating capable of accumulating electrical charge.

Abstract: A pickup cartridge for a video disc player encloses a stylus arm unit comprising a stylus arm carrying a stylus at one end and a magnetizable connector plate secured at its other end. A permanent magnet is centrally located in a recess provided in a magnetizable support member which is mounted in a carriage of the player. When the connector plate is engaged with the support member, the separation between the connector plate and the permanent magnet is greater than the separation between the permanent magnet and the walls defining the recess.

Abstract: A turntable has a central opening in which a centering spindle is snugly received for a reciprocal motion along the axis of rotation of the turntable. The centering spindle has a tapering end for engagement with walls defining a central aperture of a disc master in order to center the disc master relative to the turntable. A spring, located in the turntable central opening, biases the centering spindle in a direction such that the tapering end of the centering spindle, in engagement with the walls defining the central aperture of the disc master, urges the disc master against engaging ends of locating members, secured to the peripheral portion of the turntable, to locate a surface of the disc master in a recording plane defined by the engaging ends of the locating members. The locating members selectively occupy positions permitting installation and removal of the disc master.

Abstract: A video disc player includes a carriage supporting signal processing circuitry having an electrical input terminal. A pickup cartridge which is removably mounted in said carriage contains a stylus and an electrical connection between an electrode on said stylus and a terminal on the cartridge. The cartridge terminal engages the input terminal of the signal processing circuitry under operating conditions. During installation of the cartridge in the carriage, cartridge projections cooperate with cam surfaces provided in the carriage to hold the terminal on the cartridge in spaced relation to the input terminal until the two terminals are aligned, to prevent a shearing motion therebetween.

Abstract: An unheated cutting stylus is positioned with respect to a metal master in order to cut a groove having a quiescent groove depth less than one micrometer while relative motion is established between the cutting stylus and the metal master. The cutting stylus is vibrated about the quiescent position thereof in response to a relatively high frequency signal while cutting the groove in order to cut an information track comprising short wavelength modulation (e.g., 0.6 to 1.6 micrometers) of groove depth in the bottom of the groove having a peak-to-peak dimension less than the quiescent groove depth. The cutting stylus vibration is effected by a piezoelectric element which is mounted directly between a pedestal and the cutting stylus by means of bonding materials. The pedestal, the piezoelectric element, and the cutting stylus are shaped to form a cutterhead structure having all external surfaces disposed in anti-parallel relationship to each other.

Abstract: A pickup cartridge encloses a stylus arm carrying a stylus at one end thereof. The other end of the stylus arm is secured to a connector plate via a compliant member. A spring releasably clamps the stylus arm in a retracted position. A pair of elastic straps extend between a pair of spaced end ribs. The rear end of the cartridge has a pair of hooks for releasably retaining the pair of spaced end ribs. The rear surfaces of the elastic straps are at a certain angle with respect to the front surfaces thereof. The connector plate is secured to the slanted rear surfaces of the elastic straps to establish an angular orientation of the connector plate relative to the cartridge so that, when the stylus arm is held in the retracted position in the cartridge, the compliant member is unstressed. The connector plate is adapted to be rotated upon reception of the cartridge in a player to permit the stylus arm to protrude outside the confines of the cartridge without stressing the compliant member.

Abstract: A system for playing back prerecorded signals from a spirally-grooved and rotatable record includes a carriage mounted for lateral motion relative to a motorboard of the system in correlation with lateral motion of a groove-riding stylus during playback. A stylus arm cartridge, enclosing a stylus arm supporting a stylus at one end thereof, is subject to reception in a compartment provided in the carriage. The second end of the stylus arm is pivoted in the cartridge. A first end of a leaf spring, provided for urging the stylus into the record groove during playback, is secured to the stylus. A second end of the leaf spring is secured to a ball which is friction loaded into a socket provided in the cartridge. Adjustment of angular orientation of the ball in the socket provides control of the stylus/record tracking pressure, and the lateral position of the stylus arm in the cartridge.

Abstract: An electron optical column apparatus, including a source of electrons, is operable in either a setup or a probe mode. In the setup mode, the electron source is magnified in an image plane for examination of the source by a Faraday cup prior to operation of the column in the probe mode. In the probe mode, the electron source is demagnified on an object surface, for example, for recording video signals on a record medium.

Abstract: An electron gun apparatus comprises a cathode subassembly which is movably mounted relative to a fixedly mounted and registered grid/anode subassembly to permit mechanical adjustment of the cathode with respect to the grid/anode subassembly. An evacuated chamber, including resilient bellows interconnecting the movably mounted cathode assembly to the fixedly mounted grid/anode subassembly for permitting the mechanical adjustment, houses the cathode and the grid/anode subassemblies. Means are provided for electrical energization of the cathode, the grid, and the anode. According to a further feature of the invention, the cathode comprises a line filament, and the grid and the anode are slotted for providing an elongated line image.

Abstract: In a video disc player including a base, an information disc record mounted on a turntable for rotation relative to the base, a support housing carrying a signal pickup, and a lid for supporting the support housing, an overhead signal pickup drive is provided. A centering collar is rotatably suspended in the lid by a plurality of spring elements such that, when the lid is secured onto the base for playback, the axis of rotation of the collar coincides with that of the turntable. A plurality of friction pads are affixed to the collar such that, when the lid is closed, the friction pads are pressed against the unrecorded surface of the disc record and thereby transmitting rotation of the disc record to the collar when the player is operative. The rotation of the collar is transformed into a linear motion of the support housing, carrying the signal pickup, by various right-angle drives and clutch arrangements.

Abstract: Heated material is injected into an annular cavity, defined by a pair of mold-halves, through a sprue passage, defined by a sprue bushing and an end portion of a punch. The annular cavity and the sprue passage form, respectively, the centrally apertured part and a sprue. After partial cooling of the heated material, the punch is locked in place while the annular cavity is displaced relative to the sprue passage so that the sprue is severed from the part along the peripheral surface of the punch end portion. The mold halves are separated to open the annular cavity while the sprue is resting on the punch end portion, and while the part is held by the punch end peripheral surface. After the mold halves are separated, a sprue ejector member and a part ejector member are actuated to eject, respectively, the sprue and the part from the punch end portion.

Abstract: One type of video disc reproducing system senses the capacitance between a stylus and a disc record to reconstruct the video information. The stylus includes a thin conductive element or electrode and rides in a groove of the record, which is rotated at high speeds. The record includes a conductive layer covered with a thin dielectric material. A velocity correction system comprising a closed-loop feedback system provides an advantageous means to vary the position of the pickup means relative to the moving record. This positioning maintains the relative velocity between the two substantially constant for a given radius from the center of rotation, thus correcting for residual velocity errors. There is disclosed a transducer apparatus which is mechanically coupled to the signal pickup means and electrically coupled to circuitry providing a velocity error signal. The transducer has a stationary portion which includes means for generating a magnetic flux.

Abstract: In a video disc system for recovering prerecorded signals from a disc record by a signal pickup including a turntable, turntable drive means, and turntable speed adjusting means, a turntable speed control system is provided for maintaining the rotation of the turntable at a predetermined speed. Means responsive to the rotation of the turntable generate sample pulses having a frequency which is a function of the actual speed of rotation of the turntable. The sample pulse occur at a predetermined frequency when the turntable is rotating at the predetermined speed. Means are employed for generating a sawtooth-shaped reference wave having a frequency which is a multiple of the predetermined frequency. A sample-and-hold circuit is coupled to the sample pulse generating means and reference wave generating means for determining the magnitude of the reference wave during the occurrence of each of the sample pulses for developing a speed error correction signal.

Abstract: A stator having a mating surface is fixedly mounted in a pickup arm housing of a disc record player. A rotor, also having a mating surface, is rotatably mounted such that the stator and the rotor mating surfaces are juxtaposed with a thin deposit of damping material interposed therebetween. A pickup arm rest is secured to the rotor for supporting a pickup arm which is pivoted at one end thereof in the housing. A cord is secured to the rotor for causing rotation thereof in a direction that causes the arm rest to lift the pickup arm away from the player turntable when the player is inoperative. When the cord is released, the rotor is free to rotate. A coil spring biases (1) the damped mating surfaces of the stator and the rotor toward each other, and (2) the rotor in a direction that causes the arm rest to lower the pickup arm toward the turntable, in order to effect a smooth landing of a delicate signal pickup on a disc record disposed on the turntable for playback when the cord is released.

Abstract: In a system for playing back prerecorded signals from a centrally apertured and grooved disc record having an exposed conductive region surrounding the aperture susceptible of accumulating electrical charge of sufficient magnitude to damage a groove-engaging signal pickup for transducing the disc record, an apparatus for inhibiting a plurality of disc records from being disposed on the player turntable while grounding the conductive region of a disc record disposed on the turntable is provided. An engaging member is mounted to a centering spindle secured to the turntable for rotation in a first and a second direction in response, respectively, to the passage of a disc record to-and-from a playback position of the disc record on the turntable. If a disc record is disposed on the turntable, the conductive region of the disc record is located remote from the turntable.

Abstract: A single frame color encoding/decoding system for video cassette or film chain applications is disclosed which requires neither an unusually stable transport mechanism, nor a color television camera in the playback system. The color content of the scene modulates two high frequency (e.g., 1,000 lpi) spatial carriers in the encoded transparency arranged in quadrature. A monochromatic light source projects, a seriatim, a set of transparencies. A grating is rigidly fixed to the frame of a scanner adjacent to the transparency. The grating consists of a superposition of two unmodulated low frequency (e.g., 300 and 400 lpi) spatial carriers also oriented in quadrature. The color content of the scene is optically transferred from the transparency onto relatively stable and low frequency spatial carriers of the grating. A focusing lens, situated along the optical path, obtains a diffraction pattern of the product of the transparency and the grating in the Fourier transform plane.

Abstract: A pickup arm has an intermediate portion interconnecting a first end portion and a second end portion. An end of the first end portion is secured to a supporting structure of a disc record player. During playback the first and second end portions are substantially parallel to the turntable surface of the player, and the intermediate portion positions the second end portion near the turntable surface. A signal pickup holder carrying a signal pickup is pivoted to an end of the second end porton remote from the pickup arm supported end in a manner that normally aligns the axes of the holder and the second end portion.

Abstract: A bimorph element is interposed between a supporting structure of a video disc player and a support member. A replaceable pickup arm unit carrying a signal pickup which is subject to engagement with a spirally grooved video disc record is releasably secured to the support member. The bimorph element selectively deflects the support member in a manner that displaces the groove-riding signal pickup radially of the disc record.

Abstract: In a system for playing back prerecorded signals from a spirally grooved disc record by a groove-engaging signal pickup secured to a pickup arm when relative speed is established therebetween, a locked groove escape apparatus is provided. A transducer varies the position of the signal pickup in relation to the groove in a manner that opposes deviations of the relative speed from a predetermined speed. A carriage housing the pickup arm is mounted on the player base for movement between a playback mode and a standby mode. The carriage is driven radially inward in synchronization with rotation of the disc record during playback independent of radial motion of the signal pickup due to the spiral groove. A locked groove detector coupled to the transducer generates a locked groove recognition pulse when the signal pickup encounters a locked groove.

Abstract: A cutterhead assembly suitable for forming a topographic signal-representative pattern in a recording medium such as a disc is constructed with non-parallel external surfaces so as to provide a response relatively free of undesired resonant modes over a relatively wide frequency range. The cutterhead includes a cutting stylus supported in a stylus mount. The stylus mount and therefore the stylus are driven by a piezoelectric element which is mounted on a supporting pedestal. A resilient mounting means is utilized to fasten the supporting pedestal to a mounting bracket.