Optical information recording medium
US4940618A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 14, 1989 |
| Grant date | Jul 10, 1990 |
| Priority date | — |
| Expiry date | Apr 14, 2009 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31678
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An optical information recording medium of the type wherein recorded data signals are reproduced by scanning them with a laser beam. The medium comprises a ROM region where optically readable pits are already formed and an information recordable region where optically readable pits can be formed by irradiation with a writing laser beam. The infomation recordable region comprises a light transmitting substrate having a deformable surface, a light absorptive layer overlaying the deformable surface, which absorbs the writing laser beam, and a light reflective layer overlaying the light absorptive layer. The deformable surface is deformable by energy generated upon absorption of the writing laser beam by the light absorptive layer, to thereby form optically readable pits.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.