Abstract: An inkjet printer has a printhead in which all of the inkjets are used for printing, but at a less than maximum available ejection output. When a failed inkjet is identified, the ejection throughput is increased for inkjets that print pixels in an at least two pixel neighborhood about a missing pixel, so the pixels to be printed by the failed inkjet are printed by inkjets that print pixels in the two pixel wide neighborhood.

Abstract: A method processes image data for a color separation to reduce visible perception of misalignment of printheads in a plurality of serially arranged printheads. The method includes detecting cross-process edges in image values for objects in a color separation to be printed by a plurality of serially arranged printheads, and disproportionately mapping image values corresponding to the object in the color separation to one of the printheads in the plurality of serially arranged printheads.

Abstract: A method enables an operator to detect misalignment of printheads that eject clear ink in an inkjet printer. The method prints a first test pattern with a first color of ink and then prints a second test pattern of clear ink on top of the first test pattern. The ink of the first and the second test patterns is then spread to enable the clear ink to be dispersed in interstitial spaces in the ink of the first color. An operator is then able to detect the spatial relationship of predetermined marks in the second test pattern to predetermined marks in the first test pattern. The predetermined marks of the first and the second test patterns are arranged to enable an operator to detect a misalignment distance and the inkjet printer uses the misalignment distance entered by the operator to adjust the alignment of the printheads that eject clear ink.

Abstract: A printing device can be configured with different numbers of ink colors and ink types to print with a different cross-process direction print resolution for each ink color and ink type. The printing device includes a plurality of printhead arrays with each printhead array being configured to eject ink onto an image receiving surface at a first print resolution in a cross-process direction. Each ink supply in a plurality of ink supplies is configured to provide ink to one printhead array in the plurality of printhead arrays, and a controller is configured to operate the printhead arrays at one of at least two combinations of ink colors and ink types. The controller operates the printhead arrays ejecting a same ink color or a same ink type at a second print resolution in the cross-process direction that is different than the first print resolution.

Abstract: An imaging device includes a media transport system configured to transport print media along a media path. A first print station is positioned along the media path that is configured to apply ink to a first side of the media. A first fixing assembly is positioned along the media path downstream from the first print station. A second print station is positioned along the media path downstream from the first fixing assembly that is configured to apply ink to a second side of the media. A second fixing assembly is positioned along the media path downstream from the second print station. A heater is positioned along the media path downstream from the second fixing assembly that is configured to heat the media to a gloss reducing temperature.

Abstract: A method enables linear web velocities generated with reference to angular velocity signals generated by encoders at different rollers in a double reflex printing registration system to be equalized. The method includes identifying a low frequency component of a first linear velocity of a moving web, identifying a high frequency component of a second linear velocity of the moving web, and computing a linear velocity for the moving web at a roller in a print zone with reference to the identified high frequency component of the second linear velocity and the identified low frequency component of the first linear velocity.

Abstract: An inkjet printer has a printhead in which all of the inkjets are used for printing, but at a less than maximum available ejection output. When a failed inkjet is identified, the ejection throughput is increased for inkjets that print pixels in an at least two pixel neighborhood about a missing pixel, so the pixels to be printed by the failed inkjet are printed by inkjets that print pixels in the two pixel wide neighborhood.

Abstract: A method of operating a printer enables printheads mounted on print bars to be operated to compensate for misalignment of printheads in the process direction. The method includes identifying a position in the process direction for each printhead in a plurality of printheads, selecting one of the identified printhead positions as a reference printhead position, identifying a printhead timing parameter for each printhead mounted to at least one print bar, generating a firing signal for the printheads mounted to the at least one print bar, and adjusting delivery of the firing signal by the identified printhead timing parameter for each corresponding printhead mounted to the at least one print bar to coordinate actuation of inkjet ejectors in the printheads mounted to the at least one print bar and compensate for misalignment of the printheads in the process direction.

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 method enables a controller to align printheads in a printer. The method includes identifying a first cross-process position for each printhead in a plurality of printheads in a printer with reference to image data of a test pattern printed by the plurality of printheads on a media substrate, identifying a second cross-process position for each printhead in the plurality of printheads, calculating a printhead cross-process position error between the identified first cross-process position and the identified second cross-process position for each printhead, comparing a maximum printhead cross-process position error to a predetermined threshold, and operating a plurality of actuators with reference to the calculated printhead cross-process position errors to reposition the printheads in the plurality of printheads in response to the maximum printhead cross-process position error being equal to or less than the predetermined threshold.

Abstract: A modular printing device has been developed that may be configured with different numbers of ink colors and ink types and with a different cross-process direction print resolution for each ink color and ink type.

Abstract: A method improves transfer efficiency of ink images on an image receiving member that were formed with small ink drops. The method includes identifying image data that correspond to ink drops that have a mass less than a predetermined threshold and that fail to comingle with another ink drop ejected with reference to the image data, modifying the identified image data to generate ink drops that comingle with at least one other ink drop ejected with reference to the image data, generating firing signals for inkjet ejectors in a print head with reference to the image data and modified image data, and ejecting in response to the firing signals a plurality of ink drops from the inkjet ejectors for each identified image data to enable a coalesced ink drop to form on an image receiving surface that has a mass that is greater than the predetermined threshold.

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 method generates a test pattern on an image receiving member that is less perceptible to human observation, but still detectable by an imaging device within a printer. A method implemented in the printer analyzes image data of the dashes in the test pattern that were randomly distributed in the process direction within an area of the image receiving member to identify positions for printheads in the printer and detect missing inkjets in the printheads.

Abstract: A method for aligning printheads, some of which are arranged in an overlapped configuration, in a printer has been developed. The method includes identifying a stitch error for each color station in a plurality of color stations in the printer. The stitch error is identified with reference to shrinkage of a print medium as the print medium passes the plurality of color stations. A portion of the stitch error is used to move at least one printhead in the color station corresponding to the stitch error to compensate for a banding issue caused by the overlapped printhead configuration. All or part of the stitch error may also be applied to other printheads in the color station to compensate for possible color to color registration issues.

Abstract: A method of operating a printer enables compensation parameters to be generated and stored in association with system conditions detected at the time of the compensation parameter generation. Upon detection of corresponding system conditions at a later time, the printer is able to use the previously generated and stored compensation parameters to adjust the timing of printhead ejections to improve the registration in ink images formed by the system.

Abstract: A system and method is provided for compensating for a faulty ink jet in a target printhead in an ink jet imaging system having a plurality of printheads arranged to span a maximum printing width that includes defining a typical printing width less than the maximum printing width and swapping the target printhead with a printhead situated in the margin outside the typical printing width. The system and method permits swapping the target printhead with a margin printhead that has a faulty ink jet provided that the location of the faulty ink jet in the margin printhead does not coincide or align with a faulty ink jet in printheads adjacent the target printhead.

Abstract: An imaging device includes an image receiving surface configured to move in a process direction in the imaging device. A plurality of printhead arrays are arranged to deposit marking material onto the image receiving surface. Each printhead array includes a plurality of printheads arrayed in a cross-process direction across the image receiving surface. Each printhead array includes at least one stitch line corresponding to a position along an axis parallel to the cross-process direction where an end of one printhead in the printhead array aligns with an end of another printhead in the printhead array. The at least one stitch line of each printhead array is offset a predetermined distance in the cross-process direction from the at least one stitch line of each of the other printhead arrays.

Abstract: A method compensates for runout errors in a web printing system. The method includes identifying runout error at a first roller driving a web of printable media, generating a runout compensation value corresponding to the identified runout error, identifying a velocity of the moving web with reference to encoder output corresponding to an angular velocity of the first roller and the generated runout compensation value, and delivering a firing signal to a print head proximate the first roller to energize the inkjet nozzles in the print head and eject ink onto the web at a position corresponding to the computed web velocity.

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.