Photodisc apparatus with gain control of tracking servo loop
US5014256A · kind A · utility
23Cited by
3References
8Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Apr 26, 1990 |
| Grant date | May 7, 1991 |
| Priority date | — |
| Expiry date | Apr 26, 2010 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/0901
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A gain control device for controlling the loop gain of a servo tracking system which enables a beam spot formed on a photodisc through an objective lens to trace a track on the disc. The gain control device opens the tracking servo loop and applied a drive signal to a lens actuator so as to move the objective lens across the tracks thereby generating tracking error signals. The device samples the tracking error signals and detects the amplitudes of these signals, and controls the loop gain such that the detected amplitudes fall within a predetermined allowable range.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.