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:
Jan. 17, 2006
Filed:
Mar. 17, 2005
Isao Ichimura, Tokyo, JP;
Kiyoshi Osato, Chiba, JP;
Jun Nakano, Tokyo, JP;
Shin Masuhara, Tokyo, JP;
Isao Ichimura, Tokyo, JP;
Kiyoshi Osato, Chiba, JP;
Jun Nakano, Tokyo, JP;
Shin Masuhara, Tokyo, JP;
Sony Corporation, Tokyo, JP;
Abstract
The present invention provides an optical recording medium and an optical disk device realizing prevention of crosswrite and uniformity of playback signals and capable of easily securing compatibility with a read only disk. It provides an optical recording medium on which light LB condensed by a lens () having a numerical aperture of 0.85±0.1 and a wavelength of 405±5 nm is focused for recording or playback, having a substrateformed with a groovein its surface, an optical recording layerformed on the substrate and having topography corresponding to the groove, and a light transmission type protection layerformed on the optical recording layer; used when light for recording or playback is focused from the protection layer side to the optical recording layer; using as a recording area only the optical recording layer of one of a side far from the emitting side of the light for recording or playback, that is, a portion corresponding to a recessed portion of the topography, and a side close to it, that is, a portion corresponding to a projecting portion; having a track pitch of 0.32±0.01 μm; and having a depth Dof a recessed portion with respect to a projecting portion in the range of 19 to 24 nm.