Patents by Inventor Jon Andreassen

Jon Andreassen 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).

  • Security device
    Patent number: 5483363
    Abstract: A security device includes first and second diffractive structures contained within a surface relief structure. The structures are such that the device responds to illumination at a first, visible wavelength to generate a first, visible pattern while any pattern generated by the second structure is not substantially visible at that wavelength, and the device responds to illumination at a second wavelength substantially different from the first wavelength to generate a second pattern suitable for machine reading while any pattern generated by the first structure is substantially suppressed relative to the machine readable pattern at that wavelength.
    Type: Grant
    Filed: July 15, 1993
    Date of Patent: January 9, 1996
    Assignee: De La Rue Holographics Limited
    Inventors: Brian W. Holmes, Kenneth J. Drinkwater, David Ezra, Jon Andreassen