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:
Sep. 26, 1995
Filed:
Jun. 14, 1994
Applicant:
Inventors:
Assignee:
Sharp Kabushiki Kaisha, Osaka, JP;
Attorneys:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G11B / ;
U.S. Cl.
CPC ...
3692751 ; 3692755 ; 369283 ; 430271 ; 430523 ; 430935 ;
Abstract
An optical disc includes a recording film formed on one surface of a disc-shaped plastics substrate having light transmission properties, and a coating film formed on the other surface of the substrate to which an optical beam is applied, in which the plastics substrate is made by injection molding and a barrier, such as a U-shaped annular groove or ridge, is circumferentially formed on the other surface, at a radial distance which is the distance from a center position to a joint position of an injection mold, and a method for manufacturing the same.