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:
Oct. 30, 2012
Filed:
Mar. 13, 2008
Masahiko Tsukuda, Osaka, JP;
Morio Tomiyama, Nara, JP;
Kenji Narumi, Osaka, JP;
Joji Anzai, Osaka, JP;
Yuuko Tomekawa, Osaka, JP;
Haruhiko Habuta, Osaka, JP;
Masahiko Tsukuda, Osaka, JP;
Morio Tomiyama, Nara, JP;
Kenji Narumi, Osaka, JP;
Joji Anzai, Osaka, JP;
Yuuko Tomekawa, Osaka, JP;
Haruhiko Habuta, Osaka, JP;
Panasonic Corporation, Osaka, JP;
Abstract
The recording/reproducing quality of a multilayer optical information recording medium deteriorate not only due to interference from other layers caused by light converging on other information layers but also due to stray light converging on the surface of a protective layer and stray light that does not converge on other information layers but rather returns to an optical head through the same optical path as the reproducing signal. The thickness composition of intermediate layers (, and) and the protective layer () in a four-layer optical information recording medium are set so as to eliminate the influence of interference caused by stray light from other layers reflected up to three times.