Optical recording and reproducing method optical recording and reproducing device, and optical recording medium
US6298018A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 8, 1999 |
| Grant date | Oct 2, 2001 |
| Priority date | — |
| Expiry date | Mar 8, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2007/13727
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An optical disk is provided with a recording layer, and with an optical coupling layer on a light-incident side of the recording layer. An optical recording and reproducing device and method include an objective lens and a hemispherical lens, which converge a light beam from a light source and project the light beam onto the optical disk. The hemispherical lens is provided in close proximity to the optical coupling layer, in a position such that an interval therebetween is not more than the wavelength of the light produced by the light source. The light beam converged by the objective lens and the hemispherical lens is coupled with the optical coupling layer while substantially maintaining a direction of propagation in which it was propagating while inside the hemispherical lens.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.