Patents by Inventor David M. Warren

David M. Warren 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: 4829568
    Abstract: A system for the metering of encrypted postage and similar indicia includes a device for printing such indicia and a device for reading such indicia. The printing is accomplished with a dot matrix printer driven by signals obtained by altering character generation signals with encryption signals. The interleaving is accomplished on a row-by-row basis by inserting delays from an encryption circuit into signals from a character generator circuit. The reading is accomplished by correlating received characters against a stored array of a symbols to determine the presence of a symbol, the extraction of coded data from character data of the received and identified character, and the comparison of the separated coded data with a reference code to determine the accuracy of the printed material. Thereby, forgery and alteration is inhibited.
    Type: Grant
    Filed: September 5, 1986
    Date of Patent: May 9, 1989
    Assignee: Pitney Bowes
    Inventors: John I. Clark, Alton B. Eckert, David M. Warren
  • Patent number: 4793908
    Abstract: A method of fabricating multiple layer, solid, thin films on a substrate having a surface to be coated, the method providing control over the thickness, stoichiometry, and morphology of each separate layer formed by a method comprising steps: A. forming a first ion beam from an inert gas; B, bombarding a target surface with said first ion beam in a vacuum chamber to generate a vapor cloud composed of the target material atoms by the process of sputtering; C. adjusting the respective positions of the substrate surface for coating and the target surface to promote the condensation of the vapor upon the substrate surface for coating; D. forming a second ion beam, the second ion beam's ions being formed from a mixture of inert and reactive gases; E.
    Type: Grant
    Filed: December 29, 1986
    Date of Patent: December 27, 1988
    Assignee: Rockwell International Corporation
    Inventors: Gene Scott, Charles W. Kohlenberger, David M. Warren
  • Patent number: 4641346
    Abstract: A system for the metering of encrypted postage and similar indicia includes a device for printing such indicia and a device for reading such indicia. The printing is accomplished with a dot matrix printer driven by signals obtained by altering character generation signals with encryption signals. The interleaving is accomplished on a row-by-row basis by inserting delays from an encryption circuit into signals from a character generator circuit. The reading is accomplished by correlating received characters against a stored array of symbols to determine the presence of a symbol, the extraction of coded data from character data of the received and identified character, and the comparison of the separated coded data with a reference code to determine the accuracy of the printed material. Thereby, forgery and alteration is inhibited.
    Type: Grant
    Filed: July 21, 1983
    Date of Patent: February 3, 1987
    Assignee: Pitney Bowes Inc.
    Inventors: John I. Clark, Alton B. Eckert, David M. Warren