Patents by Inventor Philip Cowans

Philip Cowans 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).

  • Calibration of multi-die printer
    Publication number: 20070024647
    Abstract: A multiple die printer may be calibrated by a method which includes receiving, for each die, optical density related measurements from a set of calibration targets printed on print media, each calibration target printed by nozzles of a single one of said multiple dies, the targets of each set of varying nominal optical densities, and creating linearization tables for each of said multiple dies.
    Type: Application
    Filed: July 28, 2005
    Publication date: February 1, 2007
    Inventors: Philip Cowan, Yifeng Wu, David Kinkley
  • Calibration method and apparatus using interpolation
    Patent number: 6851785
    Abstract: A systems and method for printer calibration creates linearization tables by receiving optical density related measurements for a primary ink in a group of one or more print heads printing with the primary ink, selecting from the group of print heads at least two print heads that deliver a range of optical densities when printing with the one or more primary ink, generating prebuilt linearization tables corresponding to the at least two print heads that compensate for different ink drop weights printed by the at least two print heads, and providing the prebuilt linearization tables and at least a portion of the optical density related measurements to a calibration routine that interpolates the prebuilt linearization tables to create an actual linearization table for the primary ink printed by a print head.
    Type: Grant
    Filed: September 10, 2002
    Date of Patent: February 8, 2005
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Yifeng Wu, Philip Cowan, Dongli Yang
  • Calibration method and apparatus using interpolation
    Publication number: 20040046820
    Abstract: A systems and method for printer calibration creates linearization tables by receiving optical density related measurements for a primary ink in a group of one or more print heads printing with the primary ink, selecting from the group of print heads at least two print heads that deliver a range of optical densities when printing with the one or more primary ink, generating prebuilt linearization tables corresponding to the at least two print heads that compensate for different ink drop weights printed by the at least two print heads, and providing the prebuilt linearization tables and at least a portion of the optical density related measurements to a calibration routine that interpolates the prebuilt linearization tables to create an actual linearization table for the primary ink printed by a print head.
    Type: Application
    Filed: September 10, 2002
    Publication date: March 11, 2004
    Inventors: Yifeng Wu, Philip Cowan, Dongli Yang