Multi-layer optical disk having a reflection layer comprising thin metal film and a dielectric
US6009070A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 23, 1997 |
| Grant date | Dec 28, 1999 |
| Priority date | — |
| Expiry date | Apr 23, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2007/25718
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A double-layer optical disk having characteristics that are less wavelength dependent, allows the use of a pickup comprising a light beam of a different wavelength to read each layer accurately and stably. In the double layer optical disk which comprises, a first reflection layer carrying first information, a spacer layer, and a second reflection layer carrying second information, each laminated on a transparent substrate having a specific refractive index thereby allowing a pickup to read said first and second information, the first reflection layer is formed by laminating a metal layer made of a metal thin film and a dielectric layer made of a dielectric having a refractive index higher than the refractive index of the transparent substrate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.