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:
Aug. 10, 2010
Filed:
Jul. 06, 2007
Fumiko Akagi, Fuchu, JP;
Takuya Matsumoto, Hachioji, JP;
Kimio Nakamura, Fujisawa, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
The optimum head-field intensity for saturation recording is assumed to be 560×10A/m or more. Under a condition where the recording track width of an information recording medium is equal to or less than 60 nm, the optimum head-field intensity Y satisfies the following inequalities (1) and (2):≧(−119×+4135)×1000  (1)≦(−119×+const)×1000  (2)where X denotes the nondimensional value of the recording track width divided by 10m, and Y denotes a magnetic field (expressed in units of A/m) which a magnetic pole for head-field application applies to the center of the information recording medium in the direction of the thickness thereof. Note that const=−0.8×v+33.7×v+4250 if the relative velocity v between the head and the medium at the position of the head is less than 20 m/sec, or const=4600 if the velocity v is equal to or more than 20 m/sec.