Recording medium and apparatus and method for manufacturing the same
US6687214B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 8, 2001 |
| Grant date | Feb 3, 2004 |
| Priority date | — |
| Expiry date | Apr 18, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2220/2575
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A recording medium includes pairs of groove tracks and land tracks having periodically formed bent portion provided side by side on a substrate, a plurality of land prepits previously formed on the land tracks and carrying information about the groove tracks, and a recording layer formed on at least the groove tracks and the land tracks. The land prepits have a radius of mean curvature smaller than a radius of mean curvature of sides of the groove tracks in land-prepit absent regions of the land prepits and are defined by curved surfaces continuously extending from the sides of the groove tracks. Those sides of the groove tracks which face the continuous curved surfaces of the land prepits are curved surfaces that stricture the groove tracks. The depth of the land prepit is larger than that of the groove track.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.