Optical recording medium and its designing method
US6618349B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 21, 2001 |
| Grant date | Sep 9, 2003 |
| Priority date | — |
| Expiry date | Apr 5, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/007
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In an optical recording medium of land/groove recording system, a sufficient tilt margin and a reduced cross talk are realized simultaneously with a sufficiently increased output. Provided is an optical recording medium having a light-transmitting substrate formed with grooves wherein the grooves and the region between adjacent grooves are used for the recording track, and a reading beam is irradiated through the light-transmitting substrate, wherein the relations:−12.6T+15.6≦x≦25T−3.8, and 0.55≦T≦0.68 are satisfied when the reading beam has a wavelength of &lgr;, the light-transmitting substrate has a refractive index at the wavelength &lgr; of n, the reading optical system has a numerical aperture of NA, recording track pitch is PT, the groove has a depth of &lgr;/(x·n), and T is PT/(&lgr;/NA).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.