Optical recording medium, media tracking method and recording/reproducing apparatus
US6438098B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 7, 2000 |
| Grant date | Aug 20, 2002 |
| Priority date | — |
| Expiry date | Nov 7, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/0938
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An optical recording medium capable of obtaining a large reproduced signal from the recoded mark, a large reproduced signal of a pre-pit and a large tracking signal both in an area of the grooves and an area of the pre-pits, which provides a sufficient time allowance for switching tracking to that suitable for the area of the grooves or to that suitable for the area of the pre-pits. An optical recording medium comprising a substrate whereon tracks each comprising at least of writable grooves and pre-pits deeper than or equal to the grooves are formed and areas of a relatively shallow pits are each provided between an area of the deep pits and an area of the grooves. The depth Dg of the grooves, the depth Dsp of the shallow pits and the depth Ddp of the deep pits satisfy the following conditions: Dg<&lgr;/(8n), &lgr;/(8n)<Ddp<&lgr;/(4n) and Dg≦Dsp<Ddp. Tracking method is switched over in the shallow pit area when recording or reproducing information on the optical recoding medium.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.