Patents by Inventor David Siefer

David Siefer 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: 5581052
    Abstract: A stylus for use with a digitizer tablet has a tip element that includes a front portion with a tip for engaging the surface of the tablet, and a back portion of the tip element within the stylus housing. The back portion of the tip element is adapted to apply pressure to a pressure sensitive resistance element. The front and back portions of the tip element are coupled together by a spring, in order that the tip element be resiliently compressible in the axial direction of the stylus.
    Type: Grant
    Filed: July 26, 1995
    Date of Patent: December 3, 1996
    Assignee: Summagraphics Corporation
    Inventors: Michael J. Padula, David Siefer, Frank Chiappetta, Tomas Trousil
  • Patent number: 5191480
    Abstract: An accessory for improving the accuracy, and/or facilitating the use, and/or improving aesthetics and/or ergonomics of digitizer cursors is disclosed. The accessory mounts an optical element to the position-sighting aperture on the cursor. In all embodiments, the accessory or accessories may be completely and easily removed from the cursor (and replaced). Optical elements may be interchanged and combined so as to permit the operator to select optics that are most efficient for a particular digitizer task. In particular embodiments, the lens is mounted directly to the position-sighting aperture or to another member which is directly mounted to the position sighting aperture. In some embodiments, the optical element is pivotally mounted so that it can be moved into and out of the operator's line of sight. This allows the operator to move the optical element out of his line of sight to the position-sighting aperture without removing the optical element from the cursor.
    Type: Grant
    Filed: November 13, 1989
    Date of Patent: March 2, 1993
    Assignee: Summagraphics Corporation
    Inventors: Wayne J. Murray, David Siefer, George Hesse