Video disc player with movable mirror for directing light beam onto reflective disc
AssigneeMCA Discovision, Inc.
InventorJames E. Elliott
Life of this patent
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Abstract
A video signal play back device derives video signals from a track on a video disc using a light source and an optical path to a lens system which is supported by an air bearing at a predetermined spacing from the surface of the disc. The optical path includes a mirror which is articulated for rotational motion about an axis which shifts the point of impingement of the transmitted light beam upon the disc in the radial direction. The returned beam is directed to a single photosensitive pick-up which, provides input signals to a circuit which generates a "fine" servo control signal to drive the articulated mirror. The air bearing member includes apparatus providing a bias force that varies with the radial displacement of the transducer assembly relative to the disc center.
Claims5
In a video disc playback system including a rotatable turntable adapted to carry a video disc, a player element, a turntable and a video disc carried thereby, an improved transducer system comprising:
- a. optical system means, carried on the player element including an optical path having a first portion between the disc and a radiant energy source, a second portion for applying radiant energy to the disc and for returning radiant energy reflected from the disc and a third portion for applying returned radiant energy to an energy sensitive transducer;
- b. energy beam steering means in said second path portion for directing a radiant energy beam to a precisely selected location relative to a disc and for directing the reflected portion of the applied radiant energy beam to said third portion;
- and
- c. translating means for imparting relative motion between the turntable and the player element at a predetermined rate in the radial direction for transporting said energy beam steering means in the radial direction relative to a disc.
Dependencies are inferred from the claim text.