Method of and apparatus for optically writing, reading and erasing a multi-plane record carrier, and record carrier suitable for said method and apparatus
US5408453A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 25, 1991 |
| Grant date | Apr 18, 1995 |
| Priority date | — |
| Expiry date | Mar 25, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2007/13727
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method of and an apparatus for writing and reading and/or erasing a multilayer record carrier (1) having a guide plane (2) and a plurality of recording planes (4) are described, using a guide beam (5) which cooperates with the guide plane (2) and a scanning beam (6) for at least writing in the recording planes (4). During writing the position of the scanning focus (36) formed by the scanning beam (6) is coupled to the focus (11) of the guide beam (5) which is actively controlled by using guide information which is present in the guide plane (2). During reading the scanning beam (6) is actively controlled by its own servosystem (20-28).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.