Erasable optical data storage medium having an embedded servo track and a subsurface recording interface
US4825430A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 19, 1986 |
| Grant date | Apr 25, 1989 |
| Priority date | — |
| Expiry date | Dec 19, 2006 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/244
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An erasable optical data storage medium has an embedded servo track and a subsurface recording interface. An erasable recording structure having two dyed polymer layers is separated from the servo track by a compression layer. The servo track is formed in a hard substrate which provides mechanical support for the medium. The medium is adapted to form non-vesicular data bumps projecting into the compression layer when exposed to a write laser beam of predetermined wavelength projected through the substrate and compression layer. The embedded servo track and recording interface are sufficiently close to each to be read simultaneously in the same focal plane.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.