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:
Aug. 24, 2004
Filed:
Feb. 20, 2001
Yasuaki Morimoto, Kawasaki, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
An optical information recording medium having a plurality of grooves and a plurality of lands alternately formed, where each groove and each land function as recording tracks. The medium includes a first header region having a plurality of first phase pits respectively formed on extensions of the plurality of lands, and a second header region having a plurality of second phase pits respectively formed on extensions of the plurality of grooves. Each groove has an optical depth of about 3&lgr;/8, where &lgr; is the wavelength of a light beam to be used. Each first phase pit has an optical depth that is smaller than that of each groove. Each second phase pit has an optical depth that is substantially equal to that of each groove. The first header region and the second header region are shifted from each other along the extension of each groove.