Video disc player with movable mirror for directing light beam onto reflective disc
US3944727A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 1, 1974 |
| Grant date | Mar 16, 1976 |
| Priority date | — |
| Expiry date | May 1, 1994 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/0953
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
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.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.