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:
Apr. 23, 2013
Filed:
Mar. 23, 2011
Tsutomu Aoyama, Tokyo, JP;
Isamu Sato, Tokyo, JP;
Tsutomu Aoyama, Tokyo, JP;
Isamu Sato, Tokyo, JP;
TDK Corporation, Tokyo, JP;
Abstract
An object is to provide a magnetic recording method that demonstrates an additional high assistance effect to magnetic recording by applying an alternate current magnetic field in the in-plane direction to a magnetic recording medium having a large coercive force, and a method of the present invention for magnetic recording using a magnetic recording head to a recording layer of a magnetic recording medium arranged to oppose the magnetic recording head, the magnetic recording head including a main pole, an auxiliary pole, a main coil for generating a perpendicular recording magnetic field to the main pole, and either a sub-coil for generating an in-plane alternate current magnetic field of a microwave band to the main pole or a microwave radiator that is arranged in vicinity of the main pole and that radiates microwaves, the method including: a step for modulating an amplitude of the in-plane alternate current magnetic field by modulating an amplitude of microwave alternating current that is applied to either the sub-coil or the microwave radiator using a modulation signal wave so that a ratio (fc/fm) of a carrier frequency (fc) to a modulation frequency (mf) is from 10 to 40; and a step for performing magnetic recording to the recording layer of the magnetic recording medium by applying the perpendicular recording magnetic field while applying the in-plane alternate current magnetic field with the modulated amplitude to the magnetic recording medium.