Data writing density judging method for disc
US6031802A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 12, 1998 |
| Grant date | Feb 29, 2000 |
| Priority date | — |
| Expiry date | Jan 12, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/08505
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An improved data writing density judging apparatus and method for a disc capable of judging a writing density of a disc by detecting an amount of cross talk or detecting a tracking error signal. Cross talk is detected when a disc track is scanned by a beam. A tracking error signal is detected when a pick-up member jumps a certain track while the pick-up member moves across a disc track. The improved apparatus and method computes a ratio between a minimum value and a maximum value of an envelope signal based on the detected amount of cross talk a writing density can be determined. The improved apparatus and method also converts a tracking error signal which is a high frequency analog signal into a digital signal that is used to compute a time required for a pick-up member to jump a certain track. Based on the computed time which is compared with a reference value, a writing density of a disk can also be determined.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.