Patents by Inventor Volkmar Tiefensee

Volkmar Tiefensee 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: 4633458
    Abstract: High storage density, optically-readable information carriers not only require a read-out side free of contaminants or dust for a faultless reading, but must also be protected against unintentional scratching when being handled on this side. For protection against scratches that usually occur due to dislocation of a disc deposited on its support, concentric elevations are provided that are structured under given conditions by clearances on the read-out side in the edge region and in the central region of the disc outside of the information structure which fills a concentric annular surface. The disc is able to slide on the elevations when deposited on the support without the annular surface, provided with the microstructure, coming into contact with the support.
    Type: Grant
    Filed: March 30, 1984
    Date of Patent: December 30, 1986
    Assignee: Polygram GmbH
    Inventor: Volkmar Tiefensee