Optical information recording medium and optical information recording/reproducing method
US5811217A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 9, 1994 |
| Grant date | Sep 22, 1998 |
| Priority date | — |
| Expiry date | Jun 9, 2014 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S430/146
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An optical information recording medium, which includes a substrate, and a recording thin film layer provided on the base material and adapted to form variation in an amount optically detectable by absorbing at least laser light so as to record information by partially varying the recording thin film layer and to reproduce the information by optically detecting the variation amount. The optical information recording medium further includes transparent layers each provided in contact with the recording thin film layer, and each of the transparent layers has optical thickness in which, in at least two different wavelengths .lambda., integral multiple of .lambda./2 is added to the thickness giving the large laser light absorption and large optical variation amount, respectively. More specifically, the optically detectable amount is of a reflectance factor variation, and in the different wavelengths .lambda.1 and .lambda.2, with respect to the thicknesses d1 and d2 of the transparent layers which give the optical characteristic more than 60% in the absorption, and more than 20% in the reflectance factor variation, the thickness of each transparent layer is arranged to be the thickness …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.