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. 19, 2011
Filed:
Mar. 22, 2007
Morio Tomiyama, Nara, JP;
Masahiko Tsukuda, Osaka, JP;
Haruhiko Habuta, Osaka, JP;
Panasonic Corporation, Osaka, JP;
Abstract
A multilayer information storage medium according to the present invention includes: a substrate; at least three information storage layers, which are stacked one upon the other on the substrate; a plurality of transparent layers, each of which is arranged between its associated adjacent ones of the information storage layers; and a transparent coating layer. At least two of the transparent layers have mutually different thicknesses. If a laser beam with a wavelength of 400 nm to 410 nm is incident perpendicularly on the medium through the transparent coating layer, two of the information storage layers that sandwich the thinnest one of the transparent layers have a higher returning light intensity and/or a higher degree of modulation than the other information storage layers.