Patents by Inventor Craig Eric Hadady

Craig Eric Hadady 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: 9052513
    Abstract: A system and method for reducing scan line jitter caused by facet cut variation in scan systems employing a plurality of laser sources and a sensor for generating the timing for the laser sources. The system includes a controller for determining a unique time delay for each facet of the rotating mirror, and controlling the laser sources so that video provided by each laser source is delayed in a scan line by the unique time delay corresponding to the facet of the rotating mirror used in creating the scan line.
    Type: Grant
    Filed: May 4, 2012
    Date of Patent: June 9, 2015
    Assignee: Lexmark International, Inc.
    Inventors: Fei Chen, Craig Eric Hadady, Christopher Dane Jones, Simarpreet Singh Rattan
  • Patent number: 8963976
    Abstract: The invention describes a method and system for correcting linearity error of an electrophotographic device with a reduced number of lenses. The method and system insert additional time-slices in the data being processed by the electrophotographic device. The additional time-slices are inserted in the data in a predefined order based on a plurality of random numbers. The insertion of additional time-slices corrects the linearity error of the electrophotographic device.
    Type: Grant
    Filed: September 12, 2011
    Date of Patent: February 24, 2015
    Assignee: Lexmark International, Inc.
    Inventors: Craig Eric Hadady, Christopher Dane Jones, John Lemaster
  • Patent number: 8817058
    Abstract: A system and method for reducing scan line jitter in laser scan systems employing a rotating mirror, including a controller for determining a unique time delay for each mirror facet and controlling laser sources so that video provided by each laser source is delayed in a scan line by the unique time delay corresponding to the mirror facet used in creating the scan line. The controller computes a facet map signature vector corresponding to each mirror facet matches the signature to a previously stored signature and assigns measured distance offset data to the mirror facets based upon the matching.
    Type: Grant
    Filed: May 4, 2012
    Date of Patent: August 26, 2014
    Assignee: Lexmark International, Inc.
    Inventors: Fei Chen, Craig Eric Hadady, Christopher Dane Jones, John Lemaster
  • Publication number: 20130121713
    Abstract: A system and method for reducing scan line jitter caused by facet cut variation in scan systems employing a plurality of laser sources and a sensor for generating the timing for the laser sources. The system includes a controller for determining a unique time delay for each facet of the rotating mirror, and controlling the laser sources so that video provided by each laser source is delayed in a scan line by the unique time delay corresponding to the facet of the rotating mirror used in creating the scan line.
    Type: Application
    Filed: May 4, 2012
    Publication date: May 16, 2013
    Inventors: Fei Chen, Craig Eric Hadady, Christopher Dane Jones, Simarpreet Singh Rattan
  • Publication number: 20120281996
    Abstract: A system and method for reducing scan line jitter in laser scan systems employing a rotating mirror, including a controller for determining a unique time delay for each mirror facet and controlling laser sources so that video provided by each laser source is delayed in a scan line by the unique time delay corresponding to the mirror facet used in creating the scan line. The controller computes a facet map signature vector corresponding to each mirror facet matches the signature to a previously stored signature and assigns distance offset data to the mirror facets based upon the matching.
    Type: Application
    Filed: May 4, 2012
    Publication date: November 8, 2012
    Inventors: Fei Chen, Craig Eric Hadady, Christopher Dane Jones, John Lemaster
  • Publication number: 20120002986
    Abstract: The invention describes a method and system for correcting linearity error of an electrophotographic device with a reduced number of lenses. The method and system insert additional time-slices in the data being processed by the electrophotographic device. The additional time-slices are inserted in the data in a predefined order based on a plurality of random numbers. The insertion of additional time-slices corrects the linearity error of the electrophotographic device.
    Type: Application
    Filed: September 12, 2011
    Publication date: January 5, 2012
    Inventors: Craig Eric Hadady, Christopher Dane Jones, John Lemaster
  • Patent number: 8018479
    Abstract: The invention describes a method and system for correcting linearity error of an electrophotographic device with a reduced number of lenses. The method and system insert additional time-slices in the data being processed by the electrophotographic device. The additional time-slices are inserted in the data in a predefined order based on a plurality of random numbers. The insertion of additional time-slices corrects the linearity error of the electrophotographic device.
    Type: Grant
    Filed: August 27, 2008
    Date of Patent: September 13, 2011
    Assignee: Lexmark International, Inc.
    Inventors: Craig Eric Hadady, Christopher Dane Jones, John Lemaster
  • Publication number: 20100053298
    Abstract: The invention describes a method and system for correcting linearity error of an electrophotographic device with a reduced number of lenses. The method and system insert additional time-slices in the data being processed by the electrophotographic device. The additional time-slices are inserted in the data in a predefined order based on a plurality of random numbers. The insertion of additional time-slices corrects the linearity error of the electrophotographic device.
    Type: Application
    Filed: August 27, 2008
    Publication date: March 4, 2010
    Inventors: Craig Eric Hadady, Christopher Dane Jones, John Lemaster
  • Patent number: 6292507
    Abstract: An improved spread spectrum clock generator circuit is provided which automatically compensates for variations in passive component values and system gain and charge pump current in a Phase Locked Loop circuit. The pulse widths of the UP and DOWN outputs of the Phase Frequency Detector are monitored at particular intervals to determine the deviation error of these UP and DOWN signals, as compared to typical or nominal pulse-width durations. After an error is determined in the actual values of the pulse-width durations, the Phase Locked Loop (PLL) system is adjusted depending upon the magnitude and direction of the error signal. Changes in the PLL gain parameters, especially the VCO gain and charge pump current, have a significant effect on the PFD outputs, such that the width of the UP and DOWN signals vary as the frequency changes along the spread spectrum profile. At one portion of the spread spectrum profile, the “peak” (i.e.
    Type: Grant
    Filed: September 1, 1999
    Date of Patent: September 18, 2001
    Assignee: Lexmark International, Inc.
    Inventors: Keith Bryan Hardin, Craig Eric Hadady
  • Patent number: 6229555
    Abstract: A method and apparatus provides for minimizing visual artifacts resulting from laser scan process direction position errors in an electrophotographic machine. The electrophotographic machine has defined therein a process direction, and includes a photoconductive device having an image forming surface. A printhead unit is provided for generating a laser beam, wherein the printhead unit includes optics for scanning the laser beam to form a plurality of scan lines extending across the photoconductive device in a scan direction which traverses the process direction. Adjacent scan lines of the plurality of scan lines are separated by a scan line separation distance. A controller is electrically coupled to the printhead unit for controlling the power of the laser beam during the scanning of an adjacent pair of scan lines to form a synthesized dot which lies at a synthesized position between the adjacent pair of scan lines.
    Type: Grant
    Filed: May 17, 2000
    Date of Patent: May 8, 2001
    Assignee: Lexmark International, Inc.
    Inventors: Craig Eric Hadady, Cary Patterson Ravitz
  • Patent number: 5798718
    Abstract: A method for compressing a data stream, where a first portion of the data stream is read into a window having a history buffer and look-ahead buffer. An index, based on a fourth portion of the data stream in the look-ahead buffer is used to select an entry in a pointer array. An initial entry in a record array is selected based on the pointer array entry. A third portion of the data stream is selected. The third portion is compared to a second portion in the look-ahead buffer. If the third portion does not match the second portion, then a subsequent entry in the record array is selected, and the is designated as the initial entry. These steps are repeated until either the third portion matches the second portion, or no more entries are left in the record array. When there are no more entries left in the record array, the second portion is written to the output file, and the first portion read into the window is incremented by a predetermined amount.
    Type: Grant
    Filed: May 12, 1997
    Date of Patent: August 25, 1998
    Assignee: Lexmark International, Inc.
    Inventor: Craig Eric Hadady