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:
Aug. 05, 2004
Ken'ichi Nagata, Nishinomiya, JP;
Kenichi Nishiuchi, Hirakata, JP;
Hideki Kitaura, Souraku-gun, JP;
Hideo Kusada, Osaka, JP;
Noboru Yamada, Hirakata, JP;
Shinya Abe, Kadoma, JP;
Ken'ichi Nagata, Nishinomiya, JP;
Kenichi Nishiuchi, Hirakata, JP;
Hideki Kitaura, Souraku-gun, JP;
Hideo Kusada, Osaka, JP;
Noboru Yamada, Hirakata, JP;
Shinya Abe, Kadoma, JP;
Panasonic Corporation, Osaka, JP;
Abstract
An optical information recording medium includes one or more information layers including a recording layer for recording/reproducing an information signal by irradiation with a laser light, and a seperating layer or a protective substate on which a first information layer of the information layer on the irradiation face side is formed. The seperating layer or the protective substrate having a guide groove spirally or concentrically formed on the surface, and the respective inclined planes on the inner perimeter side and the outer perimeter side of the guide groove having inclined angles α and β with respect to the bottom face of the guide groove. The guide groove has one or more dissymmetric regions in the radius direction where the inclined angles α and β are different. The information layer has roughly agreeing thicknesses in the inclined face portion on the inner and outer perimeter sides in the dissymmetric region.