Abstract: A method for operating a web printing system enables web and roller changes arising from temperature changes to be identified and used to adjust operation of the reflex registration system. The method includes identifying a temperature change for at least one roller in a web printing system, identifying a temperature change for a web moving through the web printing system at one or more locations in the web printing system, modifying web velocity computations for a reflex registration system with reference to the identified temperature change for the at least one roller and the identified temperature change for the web, and operating printheads to eject ink onto the web at positions identified with reference to the modified web velocity computations.

Abstract: A computer-implemented method for performing color registration on template media having template markings thereon.

Abstract: A method enables changes in the operation of a web printing system in response to web dimensional changes being detected. The method includes identifying a cross-process dimensional change in a web moving through a printing system, comparing the identified cross-process dimensional change to a predetermined threshold, and changing operation of a component in the web printing system in response to the cross-process dimensional change exceeding the predetermined threshold.

Abstract: A method for calibrating a printing system including a plurality of printers includes designating one of the plurality of printers as a reference printer and defining color values for a desired response for one or more printed test patches on a control page. Through a first process aimed toward achieving the desired response, a printed control page is generated with the reference printer, the control page including one or more of the test patches which, when measured, has a measured response which approaches the desired response. Through a second process aimed toward achieving a desired response, the desired response being the measured response of the reference printer, a printed control page is generated with a second of the printers, the control page including one or more of the test patches which, when measured, has a response which approaches the measured response of the reference printer.

Abstract: A printing apparatus has a substantially shiny photoreceptor imaging surface, and a photosensor array disposed to receive specularly-reflected light from the imaging surface. A quantity of toner is placed on the imaging surface, and data is derived based on light reflected from the imaging surface. The reflected light is filtered to a color effectively complementary to the toner color. The system avoids noise caused by diffusely-reflected light from powdered toner.

Abstract: Optical measurement system and method for determining a wear level of printer components such as fuser rolls. Papers can be treated with optical brighteners, which act as distinct tag/trace molecules with fluorescent properties. A fluorescence pattern on the fuser roll can be changed in accordance with the edge density distribution in the print engine, when paper edges are accumulated on the fuser roll surface. A photo detector can capture a two-dimensional, digital image of the fluorescence pattern on the fuser roll surface to be measured, after illuminating the fuser roll, with intensity near ultraviolet range, by a light source. An image processor with a parameterized model can measure changes in the fluorescence pattern by analyzing the digital image of the fuser roll surface in order to determine the level of edge wear on the fuser rolls.

Abstract: An automatic gray balance control system to produce TRCs for all primary colors in a reproduction device and for each pitch of a photoreceptor system by printing target patches for each pitch, measuring the output colors, and automatically readjusting the tone reproduction curves until a satisfactory level of accuracy is obtained as compared to the theoretical desired output. The system produces pitch-based gray balanced TRCs that are updated frequently for each pitch, with different TRCs for different pitches, to ensure consistency in output from pitch to pitch as well as from page to page on a given pitch.

Abstract: A method compensates for thermal expansion of rollers in a web print zone. The method includes receiving an angular velocity signal from a first encoder for a roller in a print zone of a moving web printing system, receiving a signal from a first temperature sensor corresponding to a temperature of the roller, modifying a first diameter for the first roller with a first predetermined distance in response to the temperature of the first roller being different than a first predetermined temperature, identifying a velocity of a moving web in the print zone of the moving web printing system with reference to the modified first diameter, and delivering a firing signal to a first printhead proximate the first roller to energize the inkjet nozzles in the first printhead and eject ink onto the web at a position corresponding to the identified moving web velocity.

Abstract: A registration system for use with an imaging device includes sensors for detecting a web speed and a web tension of a moving web and a control system configured to generate a first timing offset for at least one marking station based on the detected web speed and web tension. An image sensor is configured to generate a signal indicative of a position of a marking material applied to the moving web by at least one of the marking stations. The control system is configured to generate a second timing offset for the at least one marking station based on the position of the marking material indicated by the third signal, and to adjust an actuation time for the at least one marking station using the first timing offset and the second timing offset.

Abstract: A method of aligning a printhead is described herein. The method includes accelerating a media along a process path, controlling a first printhead to form a first mark upon the accelerating media, detecting the first mark on the accelerating media, comparing a first mark detection data with first printhead desired alignment data, determining a first correction based upon the comparison of the first mark detection data, and modifying an alignment of the first printhead based upon the determined first correction.

Abstract: Disclosed is a printing apparatus and method to correct for image non-uniformities. The printing apparatus comprises a photoreceptor (P/R) belt charging device positioned to charge the P/R belt after an image is transferred to a media sheet. Subsequently, an image sensing device scans the P/R belt residual image or patches to detect image non-uniformities.

Abstract: The present disclosure describes a system and method for controlling the post-marking heaters and ink spreading nip rollers employed for spreading the ink dots on the media web to provide the desired image quality. The technique employs a sensor for sensing single pixel linewidth and showthru sensor to sense showthru of the ink. The sensor outputs are combined with the temperature and pressure values of the ink spreading nips to provide an error signal to a PID controller for controlling the nip pressure and heater temperature.

Abstract: Systems and methods are provided for monitoring jets of an image device. The detection is implemented using a data processor that monitors information sent to a jet and using an image sensor that monitors an image being printed or an image after being printed. A detector detects the difference between the image being printed and/or the image after printing to the information sent to the jet, and identifies a faulty jet based on the difference detected.

Abstract: A system and method for controlling the cross-process position of ink print heads including identifying a first roll error frequency related to a circumference of a first roll, identifying a first roll error phase with respect to a reference location along a process path, identifying a first roll error amplitude of cross-process motion, identifying a second roll error frequency related to a circumference of a second roll, identifying a second roll error phase with respect to the reference location, identifying a second roll error amplitude of cross-process motion, and controlling the cross-process position of a first and second print head based upon the identified first roll error frequency, first roll error phase, first roll error amplitude, second roll error frequency, second roll error phase, and second roll error amplitude, wherein the first print head is axially spaced apart from the second print head along the process direction.

Abstract: A system and method for controlling the cross-process position of ink print heads including identifying a first roll error frequency related to a circumference of a first roll, identifying a first roll error phase with respect to a reference location along a process path, identifying a first roll error amplitude of cross-process motion, identifying a second roll error frequency related to a circumference of a second roll, identifying a second roll error phase with respect to the reference location, identifying a second roll error amplitude of cross-process motion, and controlling the cross-process position of a first and second print head based upon the identified first roll error frequency, first roll error phase, first roll error amplitude, second roll error frequency, second roll error phase, and second roll error amplitude, wherein the first print head is axially spaced apart from the second print head along the process direction.

Abstract: An automatic gray balance control system to produce TRCs for all primary colors in a reproduction device and for each pitch of a photoreceptor system by printing target patches for each pitch, measuring the output colors, and automatically readjusting the tone reproduction curves until a satisfactory level of accuracy is obtained as compared to the theoretical desired output. The system produces pitch-based gray balanced TRCs that are updated frequently for each pitch, with different TRCs for different pitches, to ensure consistency in output from pitch to pitch as well as from page to page on a given pitch.

Abstract: A registration system for use with an imaging device includes sensors for detecting a web speed and a web tension of a moving web and a control system configured to generate a first timing offset for at least one marking station based on the detected web speed and web tension. An image sensor is configured to generate a signal indicative of a position of a marking material applied to the moving web by at least one of the marking stations. The control system is configured to generate a second timing offset for the at least one marking station based on the position of the marking material indicated by the third signal, and to adjust an actuation time for the at least one marking station using the first timing offset and the second timing offset.

Abstract: A system and method for optically monitoring contamination of machinery includes an optical illumination source, a photodetector and an analysis module. The system and method can monitor a fuser roll, a fuser belt, or other printer module component. The optical illumination source can emit at least one illuminating frequency. The at least one illuminating frequency is configured to cause a contaminant marker to fluoresce at least one fluorescing frequency and is also configured to at least partially illuminate the machine component. The machine component contains the contaminant marker when at least partially contaminated. The photodetector is responsive to the at least one fluorescing frequency and detects the at least one fluorescing frequency emitted from the contaminated machine component. The analysis module is in operative communication with the photodetector and is figured to receive a signal therefrom.

Abstract: This is a charging assembly that is useful in marking processes with an electrostatically charged surface. The assembly includes, besides the charger, a controller and an electric field probe. Charge and current flows can be detected by the probe and corrected immediately after detection of flaws by the probe and conveyed to the controller. If flaws in the charger are determined by the probe, corrections are made to the output by a controller; this is done before a final copy or print is made. The term flaws as used means any non-uniform appearing region in the printed image or any otherwise unacceptable defect. The probe is enabled to detect and indicate flaws and the controller which is in communication with the probe takes corrective action on the flaws. The probe used is a novel probe having two sensing elements surrounded by one or more reference electrodes.

Abstract: An automatic gray balance control system to produce TRCs for all primary colors in a reproduction device and for each pitch of a photoreceptor system by printing target patches for each pitch, measuring the output colors, and automatically readjusting the tone reproduction curves until a satisfactory level of accuracy is obtained as compared to the theoretical desired output. The system produces pitch-based gray balanced TRCs that are updated frequently for each pitch, with different TRCs for different pitches, to ensure consistency in output from pitch to pitch as well as from page to page on a given pitch.