Optical memory medium with preformed pit arrangement
US5754523A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 27, 1995 |
| Grant date | May 19, 1998 |
| Priority date | — |
| Expiry date | Sep 27, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/24085
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In an optical memory medium comprising prepits on which a light spot is impinged to obtain information and, if required, guide grooves: each of those among the prepits which are longer than the diameter of the light spot consists of a series of pit portions and unpitted portions; each of the prepits is sandwiched between two of the discontinuous portions of guide grooves adjacent to each other; the guide grooves have one or more narrow portions, and each of the prepits is sandwiched between two of the narrow portions of guide grooves adjacent to each other; or the guide grooves have one or more long portions, one or more short portions, and narrow portions formed between the long and short portions, and each of the prepits is sandwiched between two of the short portions of guide grooves adjacent to each other.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.