Patents by Inventor Robert F. Hellen

Robert F. Hellen 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).

  • Publication number: 20020068198
    Abstract: In one embodiment, a data storage medium includes at least three layers. The first layer may be a substrate. The second layer includes a polymer and may exhibit surface variations. And the third layer may substantially conform to the surface variations of the second layer. The surface variations may be used to encode read-only data, servo patterns, or other tracking patterns on a data storage medium at very low cost. The surface variations may be detectable on the surface of the medium because the third layer substantially conforms to the variations. Additional layers may be added to the medium so long as they substantially conform to the surface variations such that the variations are exhibited on the surface of the medium.
    Type: Application
    Filed: December 5, 2000
    Publication date: June 6, 2002
    Inventors: Donald J. Kerfeld, Terry L. Morkved, Robert F. Hellen