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:
Feb. 26, 2002
Filed:
Sep. 08, 1998
Hiroyuki Takemoto, Miyagi, JP;
Hiroki Tsuchiya, Miyagi, JP;
Sony Corporation, Tokyo, JP;
Abstract
An optical disc has formed in an area inside the inner circumference of an information recording area formed thereon concentric or spiral continuous or discontinuous recesses at a lager pitch than the track pitch in the information recording area . The optical disc is manufactured by installing a hub substantially in the center of an optical disc substrate with reference to the recesses by positioning the hub with respect to the optical disc substrate. A stamper for manufacturing the optical disc substrates is produced by exposing a photoresist layer to a laser beam by turning on and off the laser beam while rotating a glass substrate having the photoresist layer applied thereon and scanning the laser beam radially of the glass substrate .