Patents by Inventor Igolt P. D. Ubbens

Igolt P. D. Ubbens 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).

  • Device for optically scanning a recording medium by focusing the best focus or the paraxial focus to the information layer
    Patent number: 5708638
    Abstract: An optical scanning device can scan two types of record carriers each having a transparent layer with a different thickness, in which a radiation beam scans an information layer of the record carrier through the transparent layer. When scanning a first type of record carrier the best focus of a scanning radiation beam is positioned on the information layer and when scanning a second type of record carrier the paraxial focus of the radiation beam is positioned on the information layer.
    Type: Grant
    Filed: March 14, 1996
    Date of Patent: January 13, 1998
    Assignee: U.S. Philips Corporation
    Inventors: Josephus J. M. Braat, Igolt P. D. Ubbens, James H. Coombs, Jacob Sonneveld, Jacobus P. C. Kroon, Petrus T. Jutte