Optical disc having specified track pitch, push-pull signal, and cross-track signal
US6269070A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 18, 1998 |
| Grant date | Jul 31, 2001 |
| Priority date | — |
| Expiry date | Aug 18, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/00454
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The present invention provides a rewritable optical disc which is compatible with a DVD-ROM reproduction apparatus and employs the groove recording method. The optical disc has a recording layer having a land 10 and a groove 9 onto/from which an information signal is recorded and reproduced with a light of a predetermined wavelength, wherein if it is assumed that the groove has a bottom width W1 and an opening width W2, then a groove average width X [.mu.m] can be expressed as follows: EQU X=(W1+W2)/2, and if the groove has a depth Y nm, then X and Y satisfy the following relationships: EQU Y.gtoreq.4736X.sup.2 -4764X+1239 EQU X.ltoreq.-0.000127Y.sup.2 +0.018624Y-0.075043 EQU X>0.40.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.