Patents by Inventor Freddy Gerhard Hedrikus Van Wijk

Freddy Gerhard Hedrikus Van Wijk 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).

  • Optical recording medium comprising a cross-linked buffer layer
    Patent number: 6139933
    Abstract: The invention relates to an optical recording medium, in particular to a compact disc, comprising the following layers:a) a transparent substrate with a spiral having an indented or protruding geometry; superposed byb) a recording layer; optionally superposed byc) a protective coating, wherein the recording layer comprises a partially transparent layer; superposed by a transparent buffer layer comprising a cross-linked material; superposed by a thick layer, said layers forming together a Fabry-Perot etalon.
    Type: Grant
    Filed: October 12, 1999
    Date of Patent: October 31, 2000
    Assignee: Akzo Nobel N. V.
    Inventor: Freddy Gerhard Hedrikus Van Wijk