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:
Sep. 14, 2004
Filed:
Aug. 31, 2001
Akihiko Takeo, Kunitachi, JP;
Yoichiro Tanaka, Kawasaki, JP;
Kabushiki Kaisha Toshiba, Tokyo, JP;
Abstract
There is disclosed a disk drive having a magnetic device for applying a direct current magnetic field to the disk by using a disk with a double-layered structure in which a soft magnetic layer is provided on a lower layer of the recording magnetic layer. The magnetic device generates a direct current magnetic field to uniform a magnetic domain state of the soft magnetic layer of the disk. The intensity of the direct current is larger than the anisotropic magnetic field of the soft magnetic layer and is smaller than the coercive force of the recording magnetic layer. As a consequence, the stabilization of the magnetic domain state of the soft magnetic layer of the disk can be realized to make an attempt of decreasing the magnetic noise and establishing stabilization with respect to the disturbance magnetic field.