Optical recording medium
US5882758A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 27, 1997 |
| Grant date | Mar 16, 1999 |
| Priority date | — |
| Expiry date | May 27, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31678
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A phase-change type optical recording medium, wherein (1) recording, erasing and reading of information by irradiating light is possible, and the medium has a structure in which a first protective layer, a recording layer, a second protective layer, and a reflective layer are consecutively deposited in this order on a transparent substrate, (2) the thickness of the first protective layer is in the range of the thickness, where reflectivity of light on irradiating the layer from the side of the transparent substrate exhibits a minimum, .+-.30 nm, and (3) the second protective layer has the absorption coefficient k satisfying the equation as follows EQU 0.05.ltoreq.k.ltoreq.2.5. According to the present invention, unevenness of shapes and sizes of the recording pits can be reduced, irrespective of whether the state of the recording layer is crystalline or amorphous. Resultantly, the present invention can provide an optical recording medium having an improvement in erasability and reduction of jitter, and having excellent error rate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.