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. 22, 2000
Filed:
Sep. 10, 1998
Kohichi Tateyama, Ichikawa, JP;
Hiroaki Yoda, Kawasaki, JP;
Tadahiko Kobayashi, Yokohama, JP;
Hiromi Sakata, Kawasaki, JP;
Michiko Hara, Yokohama, JP;
Akio Hori, Kawasaki, JP;
Takashi Koizumi, Kawasaki, JP;
Tomohiko Nagata, Yokohama, JP;
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
At least one magnetic pole out of a pair of magnetic poles is provided with a T-shaped magnetic pole having a magnetic pole chip at the position contacting with a magnetic gap and an auxiliary magnetic pole which is wider than thereof. The proximity of an air bearing surface of the T-shaped magnetic pole is composed of a laminated film containing a magnetic material layer with a high saturated magnetic flux density which composes the magnetic pole chip and a portion of the auxiliary magnetic pole and a magnetic material layer with a low saturated magnetic flux density which composes the remaining portion of the auxiliary magnetic pole. When the front portion of the magnetic pole with the track width of 1.8 .mu.m or less is composed of a laminated film containing a magnetic material layer having a high saturated magnetic flux density and a magnetic material layer having a low saturated magnetic flux density, the thickness of the magnetic material layer having the high saturated magnetic flux density is 0.5 .mu.m or more. According to the above described magnetic pole, the magnetic saturation near the tip portion of the magnetic pole is controlled, so that preferable magnetic field strength and magnetic field gradient can be attained when the track width is narrowed.