Patents by Inventor Ulisse Vivarelli

Ulisse Vivarelli 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).

  • Holograms having a standard reference color
    Patent number: 5812287
    Abstract: Holograms and diffraction gratings are described wherein the presence of a "key-colour" (Magenta) permits an observer to identify the position where all the other colours of the hologram in question can be univocally determined. Two set of spectra are provided such that at a predetermined angle a reference beam of incident white-light illuminating the hologram or diffraction grating composition will cause the observer to see the color "Magenta" which is to be used as a reference "key-colour".
    Type: Grant
    Filed: December 8, 1994
    Date of Patent: September 22, 1998
    Assignee: Istituto Poligrafico e Zecca Dello Stato
    Inventor: Ulisse Vivarelli