Abstract: A protective cover for a video disc record comprises a jacket and a record retaining tray removably located therein. A video disc player includes latch arms which engage the record retaining tray when an occupied cover is fully inserted into the player. Such engagement causes an extraction of the record retaining tray from the jacket during jacket withdrawal subsequent to the occupied cover arrival at the fully inserted position, whereby an enclosed record is retained in the player resting on a depressible platform upon a completion of such a jacket withdrawal. A subsequent lowering of the platform effects a transfer of the retained record to the player turntable for rotation therewith with independence from the record retaining tray.

Abstract: A system for inserting and removing a video disc into and from a player without the need for removing the video disc from its protective cover during said insertion and removal is disclosed. The system includes a clamping device built into the player for protruding into a protective cover during its insertion into the player. The clamping device precludes a removal of the enclosed video disc from the player during the subsequent cover withdrawal. The video disc is transferred to the player turntable when the lid of the player is closed. After playback, the lid is opened and an empty cover is inserted into the player. During the insertion of the empty cover, the video disc is automatically returned to the cover. The withdrawal of the cover after its full insertion into the player, removes the enclosed video disc.

Abstract: The disclosure concerns a protective package for a video disc of the type having a pair of finger holes in the label area. The package includes a base member having a well for removably receiving the video disc. A pair of rotational restraints are secured to the base member for effecting engagement with the finger holes during the containment of the video disc in the well, such engagement preventing rotational motion of the video disc relative to the base member. A cover member is secured to the base member for enclosing the video disc in the well. Pursuant to another embodiment of the present invention, the rotational restraints are removably secured to the base member, instead of being integral therewith in accordance with the first embodiment.

Abstract: A novel pickup stylus adapted for playing back prerecorded signals from a video disc has an arrowhead-shape cross-section in the region of its tip. The pickup stylus includes a dielectric support element which has a prow defining the apex of the arrowhead-shape cross-section and a substantially flat rear surface remote from the prow defining the base of the arrowhead-shape cross-section. The entire rear surface is covered with conductive material to form a narrowed-electrode in the region of its tip.

Abstract: A record support and alignment apparatus comprises a set of lifting pads secured to a depressible platform mounted in a video disc player. The lifting pads are adapted for motion between a withdrawn position and an extended position with respect to the platform. The lifting pads, in the withdrawn position, allow a record jacket to be fully inserted into the player. The lifting pads, in the extended position, support a record retained in the player such that, while the platform is disposed in an elevated position, the retained record is aligned with an empty jacket during its insertion in the player, whereby reversion of a retained record to an empty jacket is facilitated. Withdrawal of the jacket, after its full insertion in the player, removes the enclosed record from the player.

Abstract: A record extracting mechanism for a video disc player includes latch arms which alternate between (1) a retracted condition permitting arrival of a package at a fully inserted position in the player, and (2) an extended condition precluding a removal from the player of a record during a package withdrawal subsequent to an occupied package arrival at the fully inserted position, whereby a record enclosed in the package is retained in the player. The player includes means for alternating the latch arms between the two conditions in response to each package insertion into the player.

Abstract: A keel-tipped stylus comprises a tapering body, a fore-and-aft constricted terminal portion and shoulders joining the tapering body to the constricted terminal portion. To form a keel-tipped stylus, a tapering support element, made from hard material--such as diamond or sapphire-- is run on an abrasive lapping disc having a deep coarse-pitched groove. The lands on the lapping disc lap the shoulders of the keel-tipped stylus and the walls of the abrasive groove form the substantially parallel fore-and-aft surfaces of the constricted terminal portion. The abrasive groove can be deeper than the height of the keel tip; in that case, the bottom surface of the constricted terminal portion can be lapped later. Alternately, the bottom of the abrasive groove can be positioned such that it laps the bottom surface of the constricted terminal portion during the concluding portion of the keel-lapping procedure.

Abstract: A motor-driven turntable supports, for rotation therewith, a concentric ring having a plurality of permanently magnetized poles of alternate polarity symmetrically disposed along its periphery. A magnetizable core includes a pair of pole pieces having spaced surfaces defining an air gap across which magnetic flux is directed when a winding on the core is energized with alternating current. The magnetizable core is fixedly mounted such that the permanently magnetized poles pass, a seriatim, through the core gap when the turntable is rotating. The magnetized ring and the energized core form a synchronizer which opposes deviations of the turntable speed from a predetermined speed corresponding to the winding energization current frequency divided by half the number of the poles. A capacitor is connected in series with the synchronizer winding for establishing a load which exhibits a resonance at the winding energization current frequency.

Abstract: A protective cover, subject to a removable occupancy by a video disc, is inserted into a video disc player. During the insertion of an occupied cover into the player, an appropriately designed platform leads it to a fully inserted position such that a clamping device built into the player protrudes into the cover. The user then removes the cover allowing the video disc to remain in the player resting on the platform. When the player lid is closed, the platform is lowered to effect a transfer of the video disc resting thereon to the player turntable. Upon playback, the lid is raised to cause the video disc to rise with the platform. An empty cover is then inserted to return the video disc back into the cover. The subsequent withdrawal of the cover removes the enclosed video disc.

Abstract: A novel pickup stylus includes a tapering dielectric support element which has a tip defined by a prow and a relatively flat surface remote from the prow. The dielectric support element has an arrowhead-shaped cross-section in the region of its tip with the apex of the arrowhead-shape cross-section located on the prow and its base defined by the rear surface. The entire rear surface of the dielectric support element is covered with conductive material to form a narrow electrode in the region of its tip. To form a narrowed-electrode stylus, a tapering dielectric support element, having a prow and an electrode surface remote from the prow, is introduced in a trapezoidal abrasive groove while relative motion is established therebetween. The electrode face of the support element is gradually tilted toward the abrasive groove until it subtends a shallow angle therewith to form a portion having an arrowhead-shape cross-section in the region of its tip.

Abstract: A video disc package comprises a base member and a cover member hingedly secured to the base member. The members define a cavity for enclosing a centrally-apertured disc record when juxtaposed. A center post includes first and second portions attached respectively to the base and the cover members. Each of the portions has arcuate peripheral surfaces dimensioned for engagement with diametrically opposite portions of the wall defining the central aperture of the record when it is enclosed in the cavity. The first and the second portions are constructed such that they nest within the central aperture during the reception of the record in the cavity.

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: A video disc package comprises a pair of juxtaposed panels defining a cavity for enclosing a video disc and an edge opening in communication with the cavity for permitting insertion and removal of a video disc into and from the cavity. The panels have portions forming a constricted passage between the cavity and the opening. The constricted passage forming portions of the panels are covered with material effecting a cleaning of a video disc each time it is inserted into the package or removed therefrom.

Abstract: A video disc player for playing back prerecorded signals from a spirally-grooved and rotatable record includes a carriage mounted for lateral motion relative to a base plate of the player in correlation with lateral motion of a groove-riding stylus during playback. A stylus arm supported at one end within the carriage carries a stylus at the free end thereof. One end of a leaf spring for urging the stylus into the record groove is secured to the stylus. The second end of the leaf spring is mounted within the carriage above the stylus. The leaf spring (1) provides stylus tracking pressure, (2) properly locates the free end of the stylus arm relative to the carriage, (3) establishes electrical connection between an electrode on the stylus and signal processing circuitry of the player.

Abstract: A disc master, coated with an electron sensitive material, is secured to a turntable which is rotatably mounted within a vacuum chamber. A recorder column protrudes into the vacuum chamber for directing a signal representative electron beam toward the disc master. The recorder column is mounted on a carriage for translational motion along a path radially disposed with respect to the center of rotation of the turntable in correlation with the rotational motion of the turntable. A column set-up stage is mounted within the vacuum chamber, adjacent the outside perimeter of a turntable supported disc master, and in registration with the coated surface of the disc master. The recorder column is aligned with the set-up stage for determining beam characteristics, such as: beam current, shape, quality, etc., and for properly focusing the electron beam.

Abstract: A system for recording signals in a disc master comprises an electromechanical cutterhead responsive to the signals and a signal processing means interposed between the cutterhead and a signal source. The signals applied to the cutterhead are of the encoded type such that most of the signal energy is contained in signal components occupying a band of frequencies about one octave wide or less. The cutterhead is so constructed that its response to the signal components varies with frequency in substantial correspondence with the energy distribution of the maximum signal components over the afore-mentioned band. The signal processing means serves dual purposes. On the one hand, it cooperates with the cutterhead to provide a combined frequency response which is relatively uniform. On the other hand, it serves to reduce the energy level of high energy level signal components applied to the cutterhead.

Abstract: A video disc system includes an apparatus for lifting and lowering a stylus arm carrying a stylus. A permanent magnet embedded in a movably mounted element is repelled by an electromagnet to effect lowering of the stylus on a record rotatably disposed on a turntable of the video disc system. A selectively operated circuit is provided to control the rate of increase of voltage across the coil to obtain a smooth landing of the stylus on the record for playback.

Abstract: A video disc player includes a stylus arm carrying a stylus at one end thereof. The stylus is subject to engagement with a grooved record rotatably disposed on a turntable for playback. The other end of the stylus arm is pivotally secured within a stylus housing by a flexible coupler. The stylus housing is mounted for lateral motion relative to a base of said player between an off-record rest position and an over-record play position. A stylus arm rest is mounted within the stylus housing for motion between an elevated position and a depressed position. The stylus arm rest in the elevated position supports the stylus arm in a manner precluding stylus/record contact when the stylus housing is in the over-record play position. The stylus arm rest in the depressed position permits the stylus arm to occupy a lowered position. The lowered position of the stylus arm is such that the stylus/record contact is established when the stylus housing is in the over-record play position.

Abstract: A pickup cartridge for a video disc player encloses a stylus arm unit comprising a stylus arm carrying a stylus at one end thereof. A connector plate is secured to the other end of the stylus arm via a compliant member. A spring at the stylus carrying end of the stylus arm releasably retracts the stylus arm to a position within the confines of the cartridge. A diaphragm flexibly suspends the connector plate in the cartridge at an angular orientation relative to the cartridge so that, when the stylus arm is held in the retracted position in the cartridge, the compliant member is not under stress. When the cartridge is installed in the video disc player, a support member engages the connector plate to change its orientation with respect to the cartridge such as to permit the stylus to be moved to protrude outside the confines of the cartridge without bending or stressing the compliant member.

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.