| Patent Number |
Title Of Patent |
Date Issued |
| 7597418 |
System and method for adjusting ink jet uniformity based on drop mass history |
October 6, 2009 |
| A method for processing input document data uses a drop mass history for ink jets in a print head to adjust other document data processing. The method includes ejecting ink in a plurality of patterns onto an image substrate from a plurality of ink jets, each drop in a pattern corresp |
| 7564475 |
Compensation of high frequency banding in printing systems |
July 21, 2009 |
| A test pattern is written using multiple image beams in a non image zone at set time intervals. The test pattern is sensed and a profile of each beam is determined from the multiple image beams. A minimum reflectance of the profile is determined from the test pattern of each beam thereby |
| 7552986 |
Systems and methods for reducing process direction registration errors of a printhead using a li |
June 30, 2009 |
| Systems and methods are provided for detecting process direction registration errors in a printer. The errors are detected by analyzing a metric of a dash minimum response obtained from a test pattern. The test pattern contains dashes. At least one dash is shifted in the process dire |
| 7547903 |
Technique to remove sensing artifacts from a linear array sensor |
June 16, 2009 |
| Disclosed is a method and system for calibrating an image capturing sensor. The method and system include generating a test pattern on an image receiving device and measuring one or more colorimetric properties of the test pattern with an image sensor. The disclosed method and system |
| 7543911 |
Systems and methods for reducing cross process direction registration errors of a printhead usin |
June 9, 2009 |
| Systems and methods are provided for determining registration errors in the cross process direction of a printer. A first straight line is obtained by detecting line centers of a first plurality of dashes in a test pattern. A second straight line is obtained by detecting a line cente |
| 7542171 |
System and method for compensating for streaks in images using intensity variation of raster out |
June 2, 2009 |
| A method and system compensates for streak defects in an image formed using a raster output scanning device. A reflectance profile is generated from an image generated by the raster output scanning device. Thereafter, a difference profile is determined. The difference profile is determin |
| 7427118 |
Systems and methods for detecting intermittent, weak and missing jets with an inline linear arra |
September 23, 2008 |
| Systems and methods are provided for detecting intermittent, weak or missing jets of a printer. The detection is implemented using a test pattern. Detected failed jets may be confirmed using a verification target. A printhead containing nozzles corresponding to detected failed jets m |
| 7424169 |
Active compensation of streaks using spatial filtering and feedback control |
September 9, 2008 |
| An image processing method to reduce streaking on a printed sheet uses a negative feedback system to reduce streaking. The method scans a printed sheet to produce image data. The method further measures gray-levels of the image data and computes a compensation vector from the measured |
| 7400339 |
Method and system for automatically compensating for diagnosed banding defects prior to the perf |
July 15, 2008 |
| A system that extends the operational effectiveness of an image reproduction machine without requiring downtime for service by personnel includes a detection subsystem that monitors components of an image reproduction system for detecting a banding defect in the image reproduction sy |
| 7375740 |
Method and apparatus for adjusting printbar uniformity |
May 20, 2008 |
| In a printing system, a method is used for adjusting currents to LEDs in an LED printbar to achieve uniformity of the print. The line test pattern and halftone strips test pattern are printed. The test patterns are scanned. An LED line metric of each LED test pattern line and reflectance |
| 7347525 |
Systems and methods for compensating for streaks in images |
March 25, 2008 |
| Defects in an image may give rise to visible streaks, or one-dimensional defects in an image that run parallel to the process direction. One known method for compensating for streaks introduces a separate tone reproduction curve for each pixel column in the process direction. A compe |
| 7309118 |
Systems and methods for reducing cross process direction registration errors of a printhead usin |
December 18, 2007 |
| Systems and methods are provided for determining registration errors in the cross process direction of a printer. A first straight line is obtained by detecting line centers of a first plurality of dashes in a test pattern. A second straight line is obtained by detecting a line cente |
| 7295349 |
Systems and methods for compensating for print defects |
November 13, 2007 |
| Diminished intensity defects occur in electrostatic printing between image regions having grey levels, i.e., different electrostatic potential and toner densities. Such defects occur when higher density regions "steal" toner from lower density regions. The system and methods according to |
| 7283143 |
Measurement and control of high frequency banding in a marking system |
October 16, 2007 |
| A method of measuring and controlling high frequency banding, the method includes creating a test pattern, sensing the test pattern with optical sensors, determining a beat frequency based on the sensed test pattern, and determining the frequency, phase and amplitude of high frequency |
| 7256411 |
Systems and methods for improving calibration of a linear array sensor |
August 14, 2007 |
| Systems and methods provide calibration for a linear array sensor. A test pattern having a plurality of lines is used. Comparison between expected and measured spacing between a pair of neighboring lines is used to determine sensor position displacement. |
| 7193638 |
Systems and methods for sensing skew and bow of a raster optical scanner using a full width arra |
March 20, 2007 |
| System and methods are provided for detecting color separation misalignment in raster optical scanners. A dash minimum response curve is obtained from a plurality of minimal responses sensed from a plurality of dashes in a test pattern. The frequency of the dash minimum response curv |
| 7154110 |
Systems and methods for improving calibration of a linear array sensor |
December 26, 2006 |
| Systems and methods provide calibration for a linear array sensor. A test pattern having a plurality of lines is used. Comparison between expected and measured spacing between a pair of neighboring lines is used to determine sensor position displacement. |
| 7125094 |
Systems and methods for compensating for streaks in images |
October 24, 2006 |
| Defects in an image forming system may give rise to visible streaks, or one-dimensional defects in an image that run parallel to the process direction. One known method for compensating for streaks introduces a separate tone reproduction curve for each pixel column in the process dir |
| 7120369 |
Method and apparatus for correcting non-uniform banding and residual toner density using feedbac |
October 10, 2006 |
| A feedback control method for controlling an ununiform banding on a photoreceptor is disclosed that includes arranging optical sensors on a photoreceptor, transferring an amount of toner on a piece of paper, measuring the resulting amount of banding, and adjusting the parameters to d |
| 7095531 |
Systems and methods for compensating for streaks in images |
August 22, 2006 |
| Defects in an image forming system may give rise to visible streaks, or one-dimensional defects in an image that run parallel to the process direction. One known method for compensating for streaks introduces a separate tone reproduction curve for each pixel column in the process dir |
| 7090324 |
System and methods for compensating for streaks in images |
August 15, 2006 |
| Defects in an image forming system may give rise to visible streaks, or one-dimensional defects in an image that run parallel to the process direction. One known method for compensating for streaks introduces a separate tone reproduction curve for each pixel column in the process dir |
| 7054568 |
Method and apparatus for controlling non-uniform banding and residual toner density using feedba |
May 30, 2006 |
| A system and method of determining a residual toner mass on a receiving member includes providing one or more test patterns to the receiving member, transferring the test patterns from the receiving member to a transfer medium, determining a sensor signal obtained after transfer, pro |
| 6819352 |
Method of adjusting print uniformity |
November 16, 2004 |
| A method of adjusting print uniformity in a xerographic device is provided. The method includes: a) printing a test pattern, b) transferring the printed test pattern to a scanner, c) scanning the printed test pattern and detecting line information, d) communicating the detected informati |
