Patents by Inventor David B. Holland

David B. Holland 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: 4656106
    Abstract: There is described a method of preparing a silver halide sensitized hologram having interference fringes generally parallel to the substrate which comprises effecting an imagewise photographic exposure using actinic light and effecting a holographic exposure using laser light, wherein the reference beam enters the holographic material from the opposite side to the object beam, of the holographic material, the photographic exposure and the holographic exposure being either sequential or simultaneous, developing the holographic material using a silver halide developing agent and then bleaching out the developed silver.In the processed hologram a part of the holographic image when viewed by reflection exhibits a color relatively close to the laser light used for the holographic exposure when exposed for an appropriate time. However, in those areas where the photographic image would have been present before bleaching these areas exhibit a color of a shorter wavelength.
    Type: Grant
    Filed: October 15, 1985
    Date of Patent: April 7, 1987
    Assignee: Ciba-Geigy AG
    Inventors: David B. Holland, Glenn P. Wood