Protected optical disc comprising a flexible closure element
US4551733A · kind A · utility
9Cited by
3References
8Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Mar 11, 1983 |
| Grant date | Nov 5, 1985 |
| Priority date | — |
| Expiry date | Mar 11, 2003 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/24015
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A protected optical disc adapted for optical recording and playback of information (particularly digital recording) with a rigid element carrying the recording surface, and a flexible element permeable to optical radiation, one of these two elements having the shape of a dish. At least one of the elements is provided with a central hole for receiving a driving shaft, with the joined annular portion or portions of the two elements concentric with the central hole.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.