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:
Jun. 10, 2003
Filed:
Feb. 01, 2001
Hideaki Yoshimura, Shizuoka, JP;
Shinsuke Kishi, Saitama, JP;
Sony Corporation, , JP;
Abstract
An optical disc capable of preventing damages on a printing plate and an injection compression molding die capable of producing such optical disc substrate without raising the accuracy of the die are provided. An optical disc substrate according to one embodiment of the present invention has a ring-formed projected portion on the outer periphery of the printable plane slightly recessed inwardly from the outer edge of the disc. Such optical disc substrate can be produced using a molding die in which a readout-side mirror has a ring-formed groove on the inner surface thereof in the vicinity of a sliding portion between such readout-side mirror and a cavity ring.