Patents by Inventor Fred J. Harper

Fred J. Harper 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).

  • Method of making double-sided magneto-optical disks having reduced birefringence
    Patent number: 5146438
    Abstract: The invention is directed to a two-sided magneto-optical recording disk having reduced birefringence comprising a pair of single-sided magneto-optical recording disks, the entire recording sides of which are adhered together by means of a continuous layer of polymeric adhesive. An external mechanical laminating pressure in a vacuum is applied to the non-information areas of the a magneto-optical disk.
    Type: Grant
    Filed: May 30, 1990
    Date of Patent: September 8, 1992
    Assignee: E. I. Du Pont de Nemours & Co.
    Inventor: Fred J. Harper