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. 16, 1998
Filed:
Apr. 09, 1996
Masahiko Kaneko, Kanagawa, JP;
Nobuhiko Umezu, Chiba, JP;
Katsuhisa Aratani, Chiba, JP;
Ariyoshi Nakaoki, Tokyo, JP;
Sony Corporation, Tokyo, JP;
Abstract
A multilayer optical disk having an information storage layer which can as well as be reproduced by a general-purpose reproducing apparatus, for example, a compact disk player, and from which information can be read from other information storage layers by using an exclusive reproducing apparatus. The multilayer optical disk having a plurality of information storage layers according to the present invention includes a plurality of information storage layers, wherein one of the plural information storage layers has a reflection factor of 70% or higher with respect to a wavelength of 770 nm to 830 nm which is a first wavelength of reproducing light, and other information storage layers are reproduced with reproducing light having a second wavelength which is different from the first wavelength of reproducing light. Each of the other information storage layers has a reflection factor of 20% or higher with respect to the second wavelength of reproducing light. The second wavelength of reproducing light is 615 nm to 655 nm.