Double shielded magnetorestive sensing element
AssigneeInternational Business Machines Corporation
InventorCharles Chia-Hsiung Lin
Life of this patent
Estimating the term…
Abstract
A magnetoresistive sensing element used for sensing magnetic transitions includes relatively thick shields and substantially thinner shields between the thick shields and the MR element. The output pulse waveform resulting from the MR element sensing a magnetic transition is improved permitting a higher linear density. The thick shields can comprise the legs of an inductive write transducer with the thin shields and MR element interposed for the read function. Another read/write head embodiment can include a separate write tranducer with the thin shields and the MR element placed between one of the legs of a write transducer and a third magnetic shield formed from either a thick magnetic layer or a magnetic substrate.
Claims13
A head assembly for reading magnetically recorded information from a medium comprising:
- a magnetoresistive element;
- means for sensing the resistance of said magnetoresistive element to read the magnetic information from the medium;
- a plurality of magnetic sheets forming thin magnetic shields, at least one disposed spaced from and adjacent to each planar surface of said magnetoresistive element;
- a plurality of highly permeable magnetic members each having a thickness dimension greater than said thin shields, at least one disposed spaced from and adjacent to said planar surface of said thin shields opposite to the planar surface facing said magnetoresistive element;
- and
- magnetic insulation disposed among said magnetoresistive element, said thin shields and said magnetic members.
A multilayer head assembly for reading and recording magnetically recorded information on a medium comprising:
- a layer of magnetoresistive material for sensing magnetically recorded information while transversing the medium;
- a plurality of thin magnetic shield layers disposed spaced from and adjacent to opposite planar surfaces of said magnetoresistive layer with at least one disposed adjacent each opposite planar surface of said magnetoresistive layer, said thin shield layers defining the effective read gap of the head assembly;
- a pair of highly permeable magnetic members, one disposed spaced from and adjacent to each planar surface of said thin shield layers opposite to the planar surface facing said magnetoresistive layer, said magnetic members having a thickness dimension greater than said thin shield layers;
- means for selectively activating said magnetic members to record magnetic information on the medium;
- and
- magnetic insulation disposed among said magnetoresistive layer, said thin shield layers and said magnetic members.
A head assembly for reading magnetically recorded information from a medium comprising:
- a plurality of spaced apart highly permeable magnetic members;
- a magnetoresistive element placed intermediate a first and a second of said magnetic members;
- means for sensing the resistance of said magnetoresistive element to read the magnetic information from the medium;
- a magnetic shield interposed between said magnetoresistive element and each of said first and second magnetic members, each shield having a thickness dimension much less than that of the magnetic members;
- and
- magnetic insulation disposed between said magnetoresistive element and said magnetic shields, and between said magnetic shields and said magnetic members.
Dependencies are inferred from the claim text.