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:
Nov. 06, 2001
Filed:
Jun. 05, 1998
Sony Corporation, Tokyo, JP;
Abstract
An optical disc in which two optical discs are laminated together to realize high recording density and improved recording/reproducing characteristics for information signals, and a manufacturing method for the optical disc. When laminating a first disc having a first information recording portion on one surface of a first substrate to a second disc having a second information recording portion on one surface of a second substrate, the direction of warping of the first disc is set so as to be opposite to the direction of warping of the second disc, and the first disc is laminated to the second disc so that the surface of the first substrate having the first information recording surface will face the surface of the second substrate carrying the second information recording portion.