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:
Dec. 28, 2010
Filed:
Jun. 05, 2009
Mineo Moribe, Kawasaki, JP;
Masakazu Taguchi, Kawasaki, JP;
Kazuyuki Ozaki, Kawasaki, JP;
Toshiba Storage Device Corporation, Tokyo, JP;
Abstract
A magnetic disk apparatus includes a magnetic disk, a magnetic head, a servo reproduction signal generator and a magnetic head controller. The disk includes a data recording area and a servo-pattern area. The data recording area includes a non-magnetic area scattered with magnetic regions, and the servo-pattern area includes uniformly magnetized magnetic regions larger than the magnetic regions in the recording area. The magnetic head reciprocates radially of the disk, giving a magnetization direction to the magnetic regions in the data recording area and reading the magnetization direction of the magnetic regions in the data recording area and the servo-pattern area. The servo reproduction signal generator reads the servo-pattern area, using the magnetic head, via an absolute-value calculation circuit to generate a servo reproduction signal before the recording or reading with respect to the data recording area. The magnetic head controller performs recording or reproducing with respect to the data recording area by controlling the magnetic head based on the servo reproduction signal.