Patents Examined by D. J. Severin
  • Patent number: 4972284
    Abstract: A previously disclosed "C" shaped thin film deposited permanent magnetic structure of essentially symmetrical form is designed to provide a planar region of transverse field with little or no longitudinal field component. Practice of the present invention teaches asymmetrically modifying the "C" shaped magnet to restore a small controlled amount of unidirectional longitudinal field component. The symmetry is broken by either angling the direction of magnetization of the magnet relative to the symmetric geometric form of the structure, or by angling the direction of the magnetization and also changing the geometric shape of the magnet from a "C" shape to an "L" shape.The resultant field distribution of the deposited asymmetrical magnetic structure produces a magnetic field of sufficient strength for biasing the hard axis of a coplanarly deposited MR element with an additional relatively smaller magnitude unidirectional easy axis field for longitudinally biasing it.
    Type: Grant
    Filed: January 3, 1989
    Date of Patent: November 20, 1990
    Assignee: Eastman Kodak Company
    Inventors: Neil Smith, John R. Shelor