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. 13, 2007
Filed:
Aug. 03, 2001
Takuma Yanagisawa, Tsurugashima, JP;
Takayuki Nomoto, Tsurugashima, JP;
Yasumitsu Wada, Tsurugashima, JP;
Fumihiko Yokogawa, Tsurugashima, JP;
Seiichi Ohsawa, Tsurugashima, JP;
Takuma Yanagisawa, Tsurugashima, JP;
Takayuki Nomoto, Tsurugashima, JP;
Yasumitsu Wada, Tsurugashima, JP;
Fumihiko Yokogawa, Tsurugashima, JP;
Seiichi Ohsawa, Tsurugashima, JP;
Pioneer Corporation, Tokyo, JP;
Abstract
An optical disc includes an information recording layer having a record of information as a pit train with a predetermined track pitch and a light-transmissive layer formed on the information recording layer so that the information can be reproduced by a beam of light illuminated through the light-transmissive layer to the information recording layer by an objective lens. The optical disc includes a feature in that a relationship of 0.194(λ/NA)≦TP ×Tmin≦0.264(λ/NA)is satisfied, provided that the track pitch is TP, a pit shortest length is Tmin, a wavelength of the light beam is λ and a numerical aperture of the objective lens is NA. The optical disc also includes a feature in that a pit width is 120 nm or smaller in a range of a track pitch of 0.280 to 0.325 μm.