Patents by Inventor Richard F. Lehamn

Richard F. Lehamn 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: 4937636
    Abstract: A reproduction device forms a two-color output copy in a single pass mode. An original document, modified by the formation of a colored fluorescent material on selected portions thereof, is illuminated by a light source. The light reflected from the document is transmitted through a colored filter and is projected onto the surface of a monopolar photoreceptor. Light incident on a fluorescent material is absorbed over a specific wavelength range and is re-admitted at a higher wavelength. This light, and light reflected from the white background, are transmitted through a filter of a color associated with the re-emited wavelength. Light reaching the photoreceptor discharges charged areas thereon at two energy levels. The resulting latent image incorporates three separate discharge levels corresponding to the black image information, color fluorescent areas, and background areas. The black and color areas are developed with appropriate colored toner by developer units biased at the appropriate levels.
    Type: Grant
    Filed: December 12, 1988
    Date of Patent: June 26, 1990
    Assignee: Xerox Corporation
    Inventors: James D. Rees, Richard F. Lehamn