Optical information recording/reproducing apparatus
US4982394A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 27, 1988 |
| Grant date | Jan 1, 1991 |
| Priority date | — |
| Expiry date | Jul 27, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B19/04
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An optical information processing apparatus comprises an optical head having an optical system contained in a frame and effecting at least one of recording and reproduction of information by applying a light beam condensed by the optical system to a recording medium, a detector for detecting at least one of a tracking signal and a focusing signal, a controller for moving at least a portion of the optical system in accordance with at least one of the tracking signal and the focusing signal, a detector for detecting the postion of the moving portion of the optical system relative to the frame, a position controller for controlling the moving portion so as to be held in a predetermined position, on the basis of the output signal of the position detecting detector, a detector for detecting the abnormality of at least one of the tracking and focusing controls, and a switching device for alternatively operating the tracking and focusing controller and the position controller and rendering the tracking and focusing controller inoperative and operating the position controller when the abnormality of the tracking or focusing control is detected.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.