Tracking regulation circuit including apparatus for disabling coarse drive signals
US5452276A · kind A · utility
3Cited by
11References
12Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Nov 14, 1994 |
| Grant date | Sep 19, 1995 |
| Priority date | — |
| Expiry date | Nov 14, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/0948
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An optical disc record playback apparatus includes tracking circuitry for radially translating the scanning pickup device during normal playback of the disc. Coarse and fine drive circuits are responsive to tracking error signals to provide coarse and more precise radial translations respectively. The tracking error signals are monitored for the occurrence for abnormalities such as may be produced by dust on the disc surface, and responsive to the detection of such abnormalities the coarse drive system is disabled to preclude the pickup from leaving the track.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.