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. 27, 2001
Filed:
Jul. 26, 1999
Yoshihito Fukushima, Miyagi, JP;
Atsushi Takeuchi, Miyagi, JP;
Hiroyuki Takemoto, Miyagi, JP;
Kenichi Itoh, Kanagawa, JP;
Mineo Moribe, Kanagawa, JP;
Takehiko Numata, Kanagawa, JP;
Sony Corporation, Tokyo, JP;
Abstract
On the assumption that a phase difference caused by a birefringence at the substrate is &phgr;,while a one caused by the magneto-optic Kerr effect of the recording layer is &phgr;,, the magneto-optical recording medium formatted to record information in the groove meets the conditions: −20°<&phgr;,<+10° and −45°<(&phgr;,+&phgr;,)<+15°, the magneto-optical recording medium formatted to record information on the land meets the conditions: −20°<&phgr;,<+10° and −15°<(&phgr;,+&phgr;,)<+45°, and the magneto-optical recording medium formatted to record information at both the land and groove meets the conditions: −20°<&phgr;,<+10° and −15°<(&phgr;,+&phgr;,)<+15°.