Mastering machine for making an on-land recording master disk with two beam alignment servo loops
US4953152A · kind A · utility
4Cited by
7References
31Claims
0Family size
Assignees
Inventors
Key dates
| Filing date | Dec 29, 1987 |
| Grant date | Aug 28, 1990 |
| Priority date | — |
| Expiry date | Dec 29, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/26
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A mastering machine for an optical disk provided with a closed loop for controlling the incident angle of at least one of the guide groove forming beam and header forming beam which enter a condenser lens, and thereby controlling to a predetermined level the distance between a guide groove forming light spot and a header forming light spot on a photosensitive layer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.