Apparatus for detecting moving direction of light beam spot illuminated on optical information recording medium having tracks
US5022021A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 24, 1990 |
| Grant date | Jun 4, 1991 |
| Priority date | — |
| Expiry date | Jan 24, 2010 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/09
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An apparatus for detecting a moving direction of a light beam spot illuminated on an optical information recording medium having tracks, in which moving direction identifying signals are obtained in synchronized with a leading edge and a trailing edge of a tracking error signal and a prohibit signal for prohibiting to write and rewrite information of the moving direction of the light beam spot is generated in accordance with the moving direction identifying signals. In the apparatus according to the invention, writing and rewriting the information of the moving direction of the light beam spot is prohibited when the two moving direction identifying signals denote opposite moving directions, so that the moving direction of the light beam spot on the optical information recording medium can be detected without being influenced by a prepit, a dust or a flaw formed in the optical information recording medium.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.