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. 14, 2009
Filed:
Nov. 02, 2005
Naoto Matono, Saku, JP;
Yuichi Watabe, Tokyo, JP;
Naoto Matono, Saku, JP;
Yuichi Watabe, Tokyo, JP;
TDK Corporation, Tokyo, JP;
SAE Magnetics (H.K.), Ltd., Shatin, N.T., HK;
Abstract
A perpendicular magnetic recording head capable of preventing information erasing without intention at the time of non-recording through making the magnetic domain structure of a pole layer appropriate is provided. A main pole layer is formed so as to include a first pole layer portion having a first width Wwhich determines the recording track width of a recording medium and a length L, a second pole layer portion having a width which gradually expands from the first width Wto a second width Wlarger than the first width W(W>W) and a length L, and a third pole layer portion having a third width Wlarger than the second width W(W>W) and a length L. When the ratio W/(L+L+L) satisfies a relationship of W/(L+L+L)≧1.0, on the basis of the shape magnetic anisotropy of the main pole layer, the magnetic domain structure of the main pole layer is made appropriate so that an unnecessary magnetic flux is not easily leaked at the time of non-recording.