Optical data recording medium
US6697324B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 27, 2002 |
| Grant date | Feb 24, 2004 |
| Priority date | — |
| Expiry date | Sep 14, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2007/25713
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
This invention is an optical data recording medium having a substrate protective film for effectively suppressing deformation (warpage) associated with change in environmental humidity. The optical data recording medium includes a transparent substrate, a thin film layer formed on one surface of the transparent substrate, a thin film protective film formed of a resin as a main component on the thin film layer, and a substrate protective film formed of a resin as a main component on the other surface of the transparent substrate than the thin film protective film, in which the thin film layer is a single layer film or a multi-layer film including at least one of a dielectric film, a recording film and a reflective film, and the substrate protective film has a coefficient of humidity expansion that is larger than a coefficient of humidity expansion of the thin film protective film.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.