Patent · US Expired

Optical recording/reproducing apparatus for high density multilayered disks

US5768251A · kind A · utility

8Cited by
8References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 23, 1996
Grant dateJun 16, 1998
Priority date
Expiry dateJul 23, 2016

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B2007/0013
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A multi-layer optical disk includes a plurality of recording layers and each recording layer is composed of a first layer and a second layer having respective transmission indices of T1A and T2A with respect to a disk irradiation beam intensity A and having respective transmission indices of T1B and T2B with respect to a disk irradiation beam intensity B such that T1A.times.T2A=T1B.times.T2B. The interval between one recording layer and another recording layer is at least 10 times as long as a wavelength of an optical source providing the disk irradiation beams. Furthermore, the first and second layers may have respective thicknesses of H1 and H2 and respective refractive indices of N1A and N2A with respect to a disk irradiation beam intensity A and have respective refractive indices of N1B and N2B with respect to an irradiation beam intensity B such that N1A.times.H1+N2A.times.H2=N1B.times.H1+N2B.times.H2.

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