Patent · US Expired

Optical disc and method of manufacturing

US4583102A · kind A · utility

18Cited by
6References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 3, 1984
Grant dateApr 15, 1986
Priority date
Expiry dateMay 3, 2004

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S430/146
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

An optical disc comprises a resin disc substrate, a recording medium layer formed on the disc substrate, a high purity of transparent layer, and a transparent protective resin layer. The transparency of the transparent layer is larger than that of the transparent protective resin layer. A laser beam is focused on the recording medium layer through the transparent protective layer and the transparent layer. The transparent layer is a transparent adhesive layer or an air layer. The focused laser beam is not affected by foreign matter in the vicinity of the recording medium layer due to the high transparency of the transparent layer on the recording medium layer.

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