Appeal No. 96-1841
Application 08/101,324
to provide two bias fields for an MR head to operate
optimally: one bias field to bias the MR material so that
its response to a flux field is linear and one bias field in
the longitudinal direction to suppress Barkhausen noise
which originates from multi-domain activities in MR
elements. The clearest statement of this is found in the
admitted prior art to Krounbi (col. 1), incorporated by
reference in the specification at page 3, which is
considered knowledge of those of ordinary skill in the art.
However, Smith also describes these two bias fields (col. 1,
line 28 to col. 2, line 32). As to the linearizing bias
field, Smith states (col. 1, lines 35-38): "As is fairly
conventional, source of hard (vertical) axis bias field,
provided for through a variety of means, biases the
ordinarily longitudinal moment to an orientation, as
depicted." Smith discloses using a permalloy layer 32,
which is magnetized by current through the sense film 33 "so
as to set up a hard axis bias field which biases the moment
of the film 33 at about 45E relative to the direction of
current flow . . ." (col. 2, lines 64-66). Kuijk '748,
which is incorporated by reference into the specification at
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