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. 23, 2007
Filed:
May. 14, 2003
Osamu Koyama, Tokyo, JP;
Koichiro Nishikawa, Gunma, JP;
Eiji Ueda, Kyoto, JP;
Yasumori Hino, Nara, JP;
Osamu Koyama, Tokyo, JP;
Koichiro Nishikawa, Gunma, JP;
Eiji Ueda, Kyoto, JP;
Yasumori Hino, Nara, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Matsushita Electric Industrial Co., Ltd., Kadoma, JP;
Abstract
The present invention provides an optical recording medium capable of detecting groove start signals and groove end signals with an inexpensive detection circuit and allowing quick, stable clock detection and tracking pull-in, which optical recording medium is constructed in such a way that the depth Dof the grooves satisfies D/(λ/N)<0.16, where λ is a wavelength of a light beam and N is an index of refraction of a substrate, and that the distance Lbetween the groove edge and the pit closest thereto satisfies L>1.2 FWHM, where FWHM is a full width at half maximum of the light beam in the track direction.