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. 11, 2017
Filed:
Jun. 08, 2015
Applicants:
Hoya Corporation, Shinjuku-ku, Tokyo, JP;
Hoya Glass Disk (Thailand) Ltd., Amphur Muang, Lamphun, TH;
Inventor:
Kenichi Nishimori, Lamphun, TH;
Assignees:
HOYA CORPORATION, Tokyo, JP;
HOYA GLASS DISK (Thailand) LTD., Lamphun, TH;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11B 5/73 (2006.01); G11B 5/82 (2006.01); G11B 5/72 (2006.01); G11B 5/725 (2006.01);
U.S. Cl.
CPC ...
G11B 5/7315 (2013.01); G11B 5/72 (2013.01); G11B 5/725 (2013.01); G11B 5/82 (2013.01); Y10T 428/1157 (2015.01);
Abstract
With regard to a glass substrateaccording to the present invention, a value of an amendment concentricity AC that has taken into consideration Sk and/or Ku calculated from a shape profile over the whole circumference of an inside hole, or the skewness is within a predetermined range. The glass substrate for a magnetic recording medium can stably read servo information including track information stored on a magnetic disk when the glass substrate is used for an HDD.