Patents by Inventor Timothy M. Fell

Timothy M. Fell has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 5405702
    Abstract: A method for manufacturing a nonlinear, dual-axis thin-film magnetic device which can be used as an electronic article surveillance system marker. The method includes providing a substrate having a surface characterized by first and second generally perpendicular axes. A magnetic field oriented parallel to the first axis is applied on the surface of the substrate. A first stack of relatively thin thin-film magnetic layers separated by nonmagnetic thin-film layers is grown on the substrate. The relatively thin thin-tim layers are grown in the presence of the magnetic field to a thickness sufficiently thick that the layers exhibit magnetic properties that are substantially independent of surface effects, but sufficiently thin that the easy axis of magnetization is oriented parallel to the second axis. A second stack of relatively thick thin-film magnetic layers separated by nonmagnetic thin-film layers is grown on the first stack.
    Type: Grant
    Filed: December 30, 1993
    Date of Patent: April 11, 1995
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Chester Piotrowski, Timothy M. Fell