Optical information recording medium
US5090009A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 14, 1989 |
| Grant date | Feb 18, 1992 |
| Priority date | — |
| Expiry date | Apr 14, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/00452
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An optical information recording medium comprising a light transmitting substrate, a light absorptive layer overlaying the substrate to absorb a laser beam and a light reflective layer overlaying the light absorptive layer, wherein an optical parameter represented by .rho.=n.sub.abs d.sub.abs /.lambda. where n.sub.abs is the real part of the complex refractive index of the light absorptive layer, d.sub.abs is the thickness of the light absorptive layer and .lambda. is the wavelength of a reading laser beam, is 0.05.ltoreq..rho..ltoreq.0.6, and the imaginary part k.sub.abs of the complex refractive index of the light absorptive layer is at most 0.3.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.