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. 23, 2008
Filed:
Apr. 11, 2005
Takeshi Nakagawa, Kanagawa, JP;
Ikuya Tagawa, Kanagawa, JP;
Atsushi Kikugawa, Tokyo, JP;
Hitachi Global Storage Technologies Netherlands B.V., Amsterdam, NL;
Abstract
Embodiments of the invention provide a countermeasure against spike noise maintaining the data reliability of a magnetic recording layer. In one embodiment, the magnetic domain state right below and around the read head of the soft magnetic layer in the recording medium is locally and temporarily equalized using the write head, whereby, the effect of the spike noise caused by the magnetic domain boundaries (magnetic domain walls) of the soft magnetic layer on the read waveform is prevented. The read retry action of the magnetic hard disk drive is used as the trigger for the timing of the magnetic field application, thereby shortening the time for the magnetic field application.