Patents by Inventor Allen M. Roberts

Allen M. Roberts 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).

  • Halftoning implementation for interactive image editing
    Patent number: 4706077
    Abstract: A circuit for producing a "knight ordered dither" halftone pattern for a CRT and a "double spiral" halftone pattern for a xerographic printer is described. The circuit comprises a RAM for storing the threshold values, a comparator, and supporting addressing and logic parts. Also described are a program for allowing the operator to interactively generate threshold patterns, and several knight tour patterns specifically designed for a CRT using interlaced rasters.
    Type: Grant
    Filed: September 8, 1981
    Date of Patent: November 10, 1987
    Assignee: Xerox Corporation
    Inventors: Allen M. Roberts, Andrew Sangster, Zoltan Stroll