Patent · US Expired

Optical information recording medium

US5410534A · kind A · utility

20Cited by
3References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 17, 1993
Grant dateApr 25, 1995
Priority date
Expiry dateJun 17, 2013

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B7/0051
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

In an optical recording medium having concave and convex type signal pits formed on a substrate surface, a reflection layer is formed on the signal pits in such a manner that a reflection index of an interior of the signal pits is higher than a reflection index at a periphery of the signal pits with respect to a given reproduction laser beam wavelength. In an optical recording medium having a phase change recording layer which reversibly changes optical states upon application of laser energy, a structural phase difference between a reflection beam of non-recorded regions and a reflection beam of recorded regions of the optical recording medium with respect to the wavelength of a reproduction laser beam is in a range of (0.5-1.5)+2 n.pi. radians, where n is an integer. The phase change recording layer has principle components of Ge-Sb-Te or Sb-Se.

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