Two-disc laminated optical recording medium
US6169721A · kind A · utility
5Cited by
1References
7Claims
0Family size
Assignees
Inventors
Key dates
| Filing date | Aug 26, 1998 |
| Grant date | Jan 2, 2001 |
| Priority date | — |
| Expiry date | Aug 26, 2018 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/21
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An optical recording medium has a substrate having an annular grooves, a recording layer including an organic coloring matter and formed on the substrate, and a metallic reflection layer. The recording layer has a thickness so as to have an absorbance between 0.65 and 0.75. Information is recorded in the recording layer by a laser beam having a wavelength between 600 and 700 nm, using an objective lens having a numerical aperture between 0.55 and 0.70.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.