Optical disk formation member for making an optical disk substrate
US5679386A · kind A · utility
2Cited by
9References
8Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Apr 25, 1995 |
| Grant date | Oct 21, 1997 |
| Priority date | — |
| Expiry date | Apr 25, 2015 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/21
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An optical disk formation member has a center and an outer periphery. A tracking guide groove formation portion and a prepit formation portion are provided on the member. A first land plane on an internal peripheral side of the prepit formation has a depth that is different from a second land plane on the external peripheral side of the prepit formation portion. The second land plane, furthermore, is deeper than the first land plane on the internal peripheral side of the prepit formation portion.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.