The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 25, 1995
Filed:
Sep. 11, 1992
Jiro Ikeda, Shizuoka, JP;
Yoshitake Yanagisawa, Shizuoka, JP;
Sony Corporation, Tokly, JP;
Abstract
An optical disc for use as a compact disc, an optical video disc, or the like has a disc substrate of a light-transmissive material such as polycarbonate, PMMA, or the like. The disc substrate has a pattern of pits and lands formed as representing an information signal on at least one surface thereof. A thin reflective layer of a-corrosion-resistant metallic material such as an alloy of Fe, Ni, and Co is deposited on the disc substrate over the pattern of pits and lands. The optical disc is relatively inexpensive to manufacture as no protective layer needs to be deposited on the reflective layer and is also highly resistant to loss of performance with aging because the reflective layer is made of a corrosion-resistant metallic material.