Patent · US Expired

Optical recording medium

US6673411B2 · kind B2 · utility

5Cited by
4References
14Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 24, 2002
Grant dateJan 6, 2004
Priority date
Expiry dateJun 24, 2022

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/21
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A recordable optical recording medium comprising a recording layer containing an organic dye which can absorb a laser beam and a metal reflective layer directly or via another layer on a transparent supporting substrate having a pre-groove and a pre-pit, wherein the organic dye has a refractive index nk of 2.2 or more at a reproduction wavelength &lgr;2; in relation to the reproduction wavelength &lgr;2, the depths of the pre-groove and the pre-pit on the substrates are more than &lgr;2/4; and the following equations are satisfied:0.25r≦wg≦0.38r;0.25≦wp/wg≦0.75;&thgr;gr≦&thgr;pr; and&thgr;pr≦&thgr;ptwherein r is a recording laser beam diameter represented by &lgr;1/NA where &lgr;1 is a recording wavelength [&mgr;m] and NA is a numerical aperture for an object lens; wg [&mgr;m] and &thgr;gr are a half value width and a cross-section tilting angle in a substrate radial direction for the pre-groove, respectively; and wp [&mgr;m], &thgr;pr and &thgr;pt are a half value width, a cross-section tilting angle in a substrate radial direction and a cross-section tilting angle in a tangential direction for the pre-pit, respectively.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.