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:
Nov. 01, 2011
Filed:
Aug. 19, 2009
Kenya Ito, Kanagawa, JP;
Takehiko Hamaguchi, Kanagawa, JP;
Kenya Ito, Kanagawa, JP;
Takehiko Hamaguchi, Kanagawa, JP;
Hitachi Global Storage Technologies Netherlands B.V., Amsterdam, NL;
Abstract
According to one embodiment, a control method for a magnetic disk device includes writing data by varying a phase of the array period of the plurality of magnetic elements or a phase of the time period of the recording signal in one section of the track from a corresponding phase in another section of the track, reading a reproduction signal from the track, and determining a phase shift between the array period of the plurality of magnetic elements and the time period of the recording signal, based on a reproduction signal read from the one section and a reproduction signal read from the other section. In another embodiment, a magnetic disk includes a track in which magnetic elements are magnetically separated and arranged in an array period, and a phase of the array period in one section is different from a phase in another section of the track.