Optical data recording using radiation of different characteristics
US4703469A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 11, 1985 |
| Grant date | Oct 27, 1987 |
| Priority date | — |
| Expiry date | Feb 11, 2005 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/08
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Optical data storage members in which the guard bands present between data-carrying tracks of conventional data storage members are used to carry information recorded in a manner which avoids the danger of cross-talk between adjacent tracks. One preferred arrangement consists of an optical data storage member comprising an optically recordable surface having a plurality of tracks in which information may be recorded in analogue or digital form, the tracks being of a first type in which the material constituting the track is sensitive to radiation of a first predetermined characteristic and a second type in which the material thereof is sensitive to radiation of a second predetermined characteristic, wherein tracks of the first type alternate across the surface of the second type. The tracks may be constituted by a surface region (1,2,3,4,5) carrying a plurality of closely spaced grooves (11,12,13,14,15), the grooves of one track being orthogonally directed with respect to those of its adjacent tracks. The predetermined radiation characteristic can be the polarization state of the incident radiation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.