Device and method for detecting defect signals on an optical disc
US7957241B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Feb 1, 2010 |
| Grant date | Jun 7, 2011 |
| Priority date | — |
| Expiry date | Feb 14, 2030 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2220/2537
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A device for detecting defect signals on an optical disc includes a finite state machine (FSM) to control a servo system of an optical disk drive. When the FSM is in a DETECT state and defect signals are greater than thresholds, a detection counter is set to a first predetermined value and the FSM enters an ARM state. In the ARM state, when the detection counter counts zero, the FSM enters a KICK state and the detection counter is set to a second predetermined value. In the KICK state, a flag signal XDFCT is asserted. When the detection counter in the KICK state counts to zero, the FSM enters a WAIT state and the detection counter is set to a third predetermined value. When the flag signal XDFCT is asserted, corresponding servo control signals for the servo system are clamped to a programmable constant voltage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.