Patent · US Expired

Optical recording method and optical recording apparatus

US6317404A · kind A · utility

5Cited by
3References
14Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 2, 1999
Grant dateNov 13, 2001
Priority date
Expiry dateAug 2, 2019

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03H1/0465
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

Binary two-dimensional digital data can be recorded in an optical recording medium as holograms in such a way that a recording area is made sufficiently minute correspondingly to the two-dimensional digital data by adequately limiting the spread of signal light and reference light without causing loss of the data and a read error during reconstructing. Signal light of a binary two-dimensional digital data image is subjected to Fourier transform by a lens. There is disposed forwardly of an optical recording medium a shading material having a circular, semicircular, sectorial, or L-shape light transmission part 21 that allows transmission of only components of 0th to n-th (n=1, 2, or 3) orders. The signal light after Fourier transform and reference light are transmitted through the light transmission part 21 for irradiation to the optical recording medium and a Fourier transform hologram is recorded in the optical recording medium.

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