Patents by Inventor Siegbert M. Wirth

Siegbert M. Wirth 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: 4245019
    Abstract: A method for forming patterned screens for cathode ray tubes wherein a multiplicity of viewing areas are spaced in accordance with and dimensionally smaller than openings of a mask member comprising the steps of coating the inner surface of a viewing panel with polyvinyl alcohol photosensitized with dichromate; exposing the viewing panel at a first positional location to radiant energy beamed through the mask openings; moving the viewing panel to a second positional location and exposing the viewing panel to radiant energy beamed through the mask openings; developing to remove the unexposed coating from the viewing panel; treating the exposed viewing panel with a dilute organic etching composition to erode the coating exposed to the radiant energy at one of the first and second positional locations; and washing the viewing panel to remove the etching composition and eroded coating leaving polymerized coating of a dimension smaller than the openings of the mask member.
    Type: Grant
    Filed: July 31, 1978
    Date of Patent: January 13, 1981
    Assignee: GTE Products Corporation
    Inventors: Robert L. Bergamo, Thaddeus V. Rychlewski, Siegbert M. Wirth