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:
Jul. 05, 2011
Filed:
Feb. 09, 2009
Applicants:
Norihisa Shibayama, Tokyo, JP;
Yasuhiro Naka, Tokyo, JP;
Nobuaki Orita, Tokyo, JP;
Inventors:
Assignee:
The Furukawa Electric Co., Ltd., Tokyo, JP;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G11B 5/70 (2006.01); G11B 5/82 (2006.01); G21G 4/00 (2006.01);
U.S. Cl.
CPC ...
Abstract
A plurality of recording magnetization portions is arranged in a concentric manner around a center of a glass substrate. A plurality of non-magnetization portion having a thermal conductivity lower than that of the recording magnetization portions is formed each between adjacent recording magnetization portions along a circumferential direction on a main surface of the glass substrate. A mean squared roughness of a surface of an area where each of the non-magnetization portions is formed is equal to or smaller than 1 nanometer.