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:
May. 26, 2009
Filed:
Apr. 01, 2004
Morio Tomiyama, Nara, JP;
Shinya Abe, Osaka, JP;
Yuuko Kawaguchi, Osaka, JP;
Eiji Ohno, Osaka, JP;
Panasonic Corporation, Osaka, JP;
Abstract
An optical recording medium is provided with: a first substrate having first pits on one face thereof; a first reflective layer that is formed on the face bearing the first pits of the first substrate in a manner so as to reflect lands and recesses of the first pits; a second substrate that is formed on the first reflective layer, with second pits being formed on a face on the side opposite to the first reflective layer; a second reflective layer that is formed on the face bearing the second pits of the second substrate in a manner so as to reflect lands and recesses of the second pits; and a cover layer formed on the second reflective layer. In this structure, the first pit depth dthat is a difference between lands and recesses of the first reflective layer, the wavelength λ of signal-reproducing laser light and the refractive index nof the second substrate satisfy the following relational expressions: λ/(5n)≦d≦λ/(3n) and d≠λ/(4n). Moreover, the second pit depth d, which is a difference between lands and recesses of the second reflective layer, the wavelength λ of signal-reproducing laser light and the refractive index nof the cover layer satisfy the following relational expressions: λ/(5n)≦d≦λ/(3n) and d≠λ/(4n).