Magneto-optical recording medium and method for preventing the erasing of the information recorded on the magneto-optical recording medium
US4554651A · kind A · utility
5Cited by
1References
3Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jun 2, 1982 |
| Grant date | Nov 19, 1985 |
| Priority date | — |
| Expiry date | Jun 2, 2002 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B11/10595
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Disclosed is an optical recording medium having a vertical magnetization film on which information is recorded along with an optically readable sign indicating whether or not erasing of recorded information is permitted. Also disclosed is a system for recording information on the recording medium, whereby the erasing of the information recorded on the recording medium is inhibited or permitted in accordance with a sensed sign on the recording medium.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.