Laser power control in an optical recording system to compensate for variations in mark length resulting from a wobbled groove
US5675568A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 16, 1996 |
| Grant date | Oct 7, 1997 |
| Priority date | — |
| Expiry date | Jan 16, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/24082
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An apparatus and method for controlling laser power in an optical recording system in the presence of mark length variations produced by a groove wobble when an incident recording beam is off-track. An optical source supplies an incident write signal to an optical medium, such that data may be recorded on the medium during an incident write pulse as an optically-detectable mark. A reflection of the incident write signal from the medium is detected to provide a reflected write signal. A mark formation effectiveness (MFE) signal is generated from the reflected write signal to provide an indication of mark formation. A feedback circuit connected between the signal generator and the optical source controls a power level of the source in accordance with MFE signal variations produced by the wobbled groove.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.