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:
Mar. 24, 2009
Filed:
Jun. 01, 2005
Koji Mishima, Tokyo, JP;
Daisuke Yoshitoku, Tokyo, JP;
Kenji Yamaga, Tokyo, JP;
TDK Corporation, Tokyo, JP;
Abstract
An optical recording medium includes a support substrate, and a light transmission layerthat is disposed so as to come in contact with the support substrate. At least one of a refractive index of the support substrate and a refractive index of the light transmission layer, and an extinction coefficient of the support substrate and an extinction coefficient of the light transmission layer is different. As such, according to the invention, a reflective layer is not formed between the support substrate and the light transmission layer, such that the support substrate and the light transmission layer directly come in contact with each other. Accordingly, since at least one of the refractive index and the extinction coefficient is different, reflection occurs at the interface between the support substrate and the light transmission layer. Therefore, data held by a plurality of pits, that are arranged on the support substrate in a spiral shape or a concentric shape, can be correctly read out.