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: Apparatus for use in playback of a color picture/sound disc record includes a stylus having a groove bottom engaging tip, with a conductive electrode having an exposed edge with an effective dimension along the groove which does not exceed the longitudinal dimension of the narrowest depressed groove bottom region of the disc; means for rotating the disc to cause variations in the capacitance exhibited between the stylus electrode and the disc's conductive layer; detection means responsive to the capacitive variations for deriving a train of impulses having a repetition rate varying in accordance with a first FM carrier, bearing modulation representative of luminance and chrominance information, and a duty cycle varying in accordance with a second FM carrier, bearing modulation representative of sound information; means for amplifying the impulse train; first filter means coupled to the amplifier output for selectively passing the first FM carrier and sidebands to a first FM demodulator to effect recovery of (

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: In a video disc player, an FM signal recovered from the disc is subject to frequency demodulation to obtain a composite color video signal. In the composite signal, chrominance information appears in the form of a modulated subcarrier buried in spectrum troughs in the midband of a wider band luminance signal. The composite signal is applied to a modulator to develop amplitude modulated carrier waves, which serve as the "normal" signal input to a 1H delay line. Comb filter circuits respond to the delay line input and output to obtain separated chrominance and luminance signal components, which are suitably processed for delivery to color image display apparatus (e.g., color television receiver). The amplitude modulated carrier wave output of the delay line is also utilized as a "substitution" signal input to the delay line, replacing the normal signal input when a defect detector, monitoring the output of the FM demodulator, indicates the onset of a picture defect.

Abstract: Circuits are disclosed for processing color encoded video signals, encoded per a format wherein a chrominance signal in the form of a modulated subcarrier is buried in spectrum "troughs" in the midband of a wider band luminance signal, an illustrative use of the encoding format being in video disc recording. The processing circuits serve, in use with composite signals developed during video disc playback, to convert an input composite signal of buried subcarrier format to an output composite signal of NTSC format. Carrier waves are amplitude modulated in accordance with composite signals developed during video disc playback, and applied to the input of a 1H delay line. Subtractive combination of the modulated carrier waves from both input and output of the delay line effects a first comb filtering action to develop a chrominance signal output in the highband location desired for output use. The delay line output is applied to an amplitude detector.

Abstract: Color picture information is recorded on a video disc together with multiple channels of sound information (e.g., a pair of stereo sound signal components). Each audio signal to be recorded modulates the frequency of a respectively different sound carrier over a respectively different low frequency deviation range. Picture carrier waves are frequency modulated in accordance with composite color video signals, including a luminance component and a chrominance component (the latter comprising a modulated color subcarrier buried in the midband of the luminance component). The duty cycle of the modulated picture carrier waves is varied in accordance with the sum of the respective frequency modulated sound carriers to form a recording signal. The color subcarrier frequency, and the respective sound carrier center frequencies correspond to different odd multiples of half the line frequency.

Abstract: A method of forming a disc having an information recording groove of regular cross-sectional shape by forming a preliminary spiral groove of trapezoidal cross-section in a disc having a relatively flat surface, and then flowing an excess of viscous material on the groove surface of the disc while rotating the disc rapidly and long enough to flow off the excess viscous material so as to leave a continuous coating of viscous material over the surface of the disc, the trapezoidal regions being covered by a coating having a relatively constant radius of curvature.

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: In a video disc player, apparatus for generating phase error signals between a reference signal recorded on a video disc record and an external reference are utilized to correct both velocity errors in the recorded signal information and phase errors in the recorded reference signal.

Abstract: Velocity and phase errors in signals derived from a rotating video disc are minimized with the use of a voltage controlled oscillator and an electromechanical transducer. A control circuit employing an active and a passive filter maintains an appropriate frequency response to the voltage controlled oscillator and electromechanical transducer in order to appropriately share a single controlling error signal.

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: When a "locked groove" condition is encountered in the playback of a video disc having sync signal recording locations non-radially aligned in successive groove convolutions, each initiation of a repeat reading of the same groove convolution(s) results in a timing disturbance of recovered sync signals. The disturbance is detected by an arrangement employing a phase locked loop responsive to the horizontal sync component of the recorded signal. A filtered error voltage output of the phase locked loop is applied to a voltage comparator to effect discrimination against noise and minor, transitory timing disturbances. A staircase voltage generator, responsive to the voltage comparator output, provides an output sufficient to trigger generation of a locked groove recognition pulse, when the voltage comparator threshold is exceeded a sufficient number of times within a selected time period to verify locked groove behavior and continuance.

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 conductive pickup arm has a first portion and a further portion. One end of the pickup arm first portion is secured to a player supporting structure by a pickup arm support. During playback, (1) the pickup arm first portion is substantially parallel to the turntable surface of the player, and (2) an end of the further portion remote from the pickup arm supported end is disposed near the turntable surface relative to the first portion. A nonconductive signal pickup holder carrying a signal pickup is pivoted to the further portion remote end by a nonconductive signal pickup holder support in a manner that normally disposes the holder axis substantially parallel to the turntable surface. An electrode incorporated in the signal pickup is coupled via the conductive pickup arm to a signal processing circuitry of the player.

Abstract: In a system for playing back prerecorded information from a disc record by a signal pickup mounted in a support housing, a signal pickup return mechanism is provided. The support housing is reciprocably mounted in the player cover by a suitable bearing. A drive mechanism drives the support housing radially inward in order to facilitate tracking of the disc record by the signal pickup. An extendible cord is provided with its ends attached to the base and the cover of the player. The cord extends when the cover is raised from the base. A leaf spring, with an open-ended slot, is attached to the support housing. The cord is threaded through the open-ended slot. A clamp secured to the cord is subject to engagement with the support housing, and is effective only in causing radially outward movement of the support housing. The clamp urges the support housing to return to a rest position when the cover is raised from the base.

Abstract: A pickup arm cartridge houses a fragile signal pickup assembly of a video disc record player to (1) protect the signal pickup assembly during storage and handling, and (2) facilitate replacement of the signal pickup assembly without any critical manual adjustments or connections. A signal pickup assembly comprises a pickup arm carrying a signal pickup at one end and having its remote end secured to a coupler by a compliant pickup arm support. The coupler is suspended in the pickup arm cartridge such that the suspension, while permitting translatory motion of the coupler, (1) maintains angular orientation of the pickup in signal transfer relation with a disc record, and (2) positions the coupler for engagement with a translatory motion imparting transducer of the player supporting structure when the cartridge is assembled in the player. A leaf spring securely holds the signal pickup assembly in the cartridge during storage and handling.

Abstract: A cartridge casing houses a fragile pickup arm unit of a video disc record player to, (1) protect the pickup arm unit during storage and handling, and (2) facilitate ready replacement of the pickup arm unit without need for any connections and adjustments. The pickup arm unit comprises a pickup arm carrying a signal pickup at one end and having its second end secured to a coupler by a compliant pickup arm support. The pickup arm unit is suspended at the second end within the casing by a pair of tabs secured to the coupler and extending therefrom for reception in a pair of openings provided in the casing. A clamp pivotally mounted in the casing engages the pickup arm to securely hold the signal pickup end of the pickup arm unit in a retracted position in the casing when the cartridge is in an unassembled condition.

Abstract: Fluid from a hydraulic pressure source is utilized to rotate and support a turntable in a vacuum chamber. Signals representative of the rotational velocity of the turntable are utilized to control the hydraulic pressure of the fluid rotating the turntable.

Abstract: A method of producing a high resolution information storage disc includes the steps of forming a grooved disc coated with an electron beam sensitive material, exposing the coated disc to a signal modulated electron beam, replicating the exposed disc to form a second disc of opposite contour, and utilizing the second disc to produce discs having positive-shaped groove and signal information.