Patent · US Expired

Data carrier for optical read-out

US4020278A · kind A · utility

32Cited by
4References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 16, 1975
Grant dateApr 26, 1977
Priority date
Expiry dateOct 16, 1995

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B7/24018
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

The present invention relates to data carriers intended for optical read out. The data carrier in accordance with the invention comprises: a first transparent material at the surface of which the information is recorded in the form of an embossed pattern; a partially transparent metal layer covers said embossed pattern and a second, thick transparent material is deposited upon the metal layer for protection purposes.

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