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US 6,274,256 B1Granted
Thin film magnetic head
AssigneeAlps Electric Co., Ltd.
InventorsToshinori Watanabe, Atsushi Sato, Akira Takahashi
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Abstract
A product (S×Bs) of a cross-sectional area of a tip portion of an upper core layer (S) (a thickness of a layer d1 by a track width Tw) and a saturation magnetic flux density thereof (Bs) is in a range of 1.5 to 10.5 μm2·T, and preferably in a range of 4.0 to 8.0 μm2·T. Further, a magnetic pole straight length L1 ranges from 3.5 to 7.6 μM. Thus, excellent NLTS and OW characteristics can be simultaneously obtained.
Claims2
A combination type thin film magnetic head comprising:
- a writing head comprising a lower magnetic core layer and an upper magnetic core layer, said lower and upper core layers separated by a coil layer for inducing a recording magnetic field in both the lower and upper core layers;
- and
- a reading head comprising a magnetoresistive layer;
- wherein the upper core layer comprises a tip portion having a constant width starting from a facing portion facing onto a recording medium to the rearward direction which is distant from the recording medium, and a rear end portion which rearwardly becomes larger in width from the tip portion;
- wherein a length dimension of the tip portion having the constant width in the distant direction from the recording medium is in a range of 3.5 to 7.6 μm;
- and
- wherein when a cross-sectional area of the tip portion is S, and a saturation magnetic flux density of a magnetic material consisting the upper core layer is Bs, the product of (S×Bs) is in a range of 1.5 to 10.5 T·μm2.
4 more elements
Dependencies are inferred from the claim text.