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. 14, 1993
Filed:
Mar. 20, 1990
Takashi Kawabe, Hitachi, JP;
Moriaki Fuyama, Hitachi, JP;
Shinji Narishige, Mito, JP;
Eizi Ashida, Hitachioota, JP;
Makoto Morijiri, Ninomiya, JP;
Masanori Tanabe, Hitachi, JP;
Hiroshi Fukui, Hitachi, JP;
Yutaka Sugita, Tokorozawa, JP;
Hiroshi Ikeda, Tokyo, JP;
Masaaki Hayashi, Odawara, JP;
Kazuo Nakagoshi, Odawara, JP;
Kanji Kawakami, Mito, JP;
Yokuo Saitoh, Kaisei, JP;
Shunichiro Kuwatsuka, Odawara, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A magnetic head for reading from and/or writing to a magnetic information storage medium has a substrate on which a plurality of thin films are formed in sequence. The films provide a magnetic circuit having a magnetic gap, a bottom pole piece and a top pole piece overlying said bottom pole piece. The top pole piece is formed as a tip portion adjoining the magnetic gap and a rear portion which makes magnetic contact with the tip portion. The rear portion is formed in the sequence after the tip portion. To ensure accurate thickness and width of the tip portion, a non-magnetic protective film is formed on the tip portion after the tip portion is formed and before the rear portion is formed.