Patents Represented by Attorney C. Douglass Thomas
  • Patent number: 5381166
    Abstract: An ink transfer printing device having improved ink dot size control. The ink transfer printing device includes an ink container for retaining ink and a perforated ink transfer surface coupled to the ink container. The ink transfer surface includes at least one concentric region on the ink transfer surface about each of the perforations to control the spread of the ink. The concentric regions form flow barriers which impede the spread of the ink at each orifice. The ink dot size control provided by the present invention facilitates continuous toning, gray scale toning and multi-color printing.
    Type: Grant
    Filed: November 30, 1992
    Date of Patent: January 10, 1995
    Assignee: Hewlett-Packard Company
    Inventors: Si-Ty Lam, An-Chung R. Lin, Young-Soo You