Abstract: An aqueous inkjet printer is configured to evaluate and adjust multiple components within the printer with reference to image data of the surface of a rotating member obtained at different times during a single print cycle. The print cycle can be performed in a multiple pass manner to enable a single optical sensor to be used for generation of the image data. Alternatively, the print cycle can be performed in a single revolution of the rotating member and multiple optical sensors positioned about the rotating member to generate the image data.

Abstract: An inkjet printer is configured to apply a coating material to an imaging surface before an ink image is formed on the surface. At least one optical sensor generates image data of the coating on the imaging surface and identifies a thickness of the coating material. Components of the coating material applicator can be adjusted to keep the thickness of the coating material within a predetermined range.

Abstract: A method compensates for changes in drop velocity of drops emitted by inkjets in a printhead of an ink jet imaging device. The method includes operating inkjet ejectors in a plurality of printheads to eject ink in a pattern of structured dashes on an image receiving member, the structured dashes corresponding to a predetermined image data pattern, generating image data corresponding to the pattern of structured dashes on the image receiving member, identifying a process direction correction parameter for each ejector in the plurality of printheads with reference to the generated image data, modifying image data to be printed by the plurality of printheads with reference to the process direction correction parameter identified for at least one of the ejectors, and operating the plurality of printheads with reference to the modified image data.

Abstract: A system cuts media printed with phase change ink in a manner that reduces the ink debris produced by cutting solidified ink. The system includes a heater configured to heat phase change ink on the media moving through the heater to a temperature at which the ink is malleable, the temperature being above room temperature and below a temperature at which phase change ink melts, and a cutter configured to receive the media after the media has been heated by the heater and to cut the media. The blade of the cutter may also be heated to facilitate media cutting with a reduced likelihood of solid ink debris being generated.

Abstract: A method for operating an inkjet printer to form images that include both high density and low density segments has been developed. The method includes operating one printhead to eject ink drops with a large size to form high density segments of the image, and operating a second printhead to eject ink drops with a small size to form low density segments of the image. The large ink drops provide high coverage in the high density segments, and the small ink drops provide improved image quality in the low density segments of the image.

Abstract: In an inkjet printer, a method for of compensating for defects in printed images identifies a cross-process direction location of a defect in a printed image and a candidate inkjet corresponding to the location of the defect. The method modifies the operation of the candidate inkjet to form a second ink image. The method identifies a second inkjet that actually formed the first image defect in response to identifying a second defect in the second ink image located proximate to the first defect. The method enables identification and compensation of inoperable inkjets when image data do not correspond perfectly to inkjets in the printer.

Abstract: A method of operating an inkjet printer reduces ink drop placement errors in a process direction. The method includes generating firing signals for inkjets in a printhead at a first frequency and initiating the generation of the firing signals to a first plurality of inkjets in the printhead at a second frequency, the first frequency being greater than the second frequency.

Abstract: An imaging device includes a media supply and handling system configured to move media along a path. A printing system is disposed along the path that includes at least one printhead for applying melted phase-change ink of at least one color to the media to form images thereon. A fixing assembly is disposed along the path downstream of the printing system that is configured to apply heat and/or pressure to the melted phase change ink of the images on the media. A coating system is disposed along the path downstream from the spreader. The coating system includes at least one printhead for applying a clear ink on top of the images formed on the media by the printing station.

Abstract: In an inkjet printer, a method for of compensating for defects in printed images identifies a cross-process direction location of a defect in a printed image and a candidate inkjet corresponding to the location of the defect. The method modifies the operation of the candidate inkjet to form a second ink image. The method identifies a second inkjet that actually formed the first image defect in response to identifying a second defect in the second ink image located proximate to the first defect. The method enables identification and compensation of inoperable inkjets when image data do not correspond perfectly to inkjets in the printer.

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 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 method for operating an inkjet printer to form images that include both high density and low density segments has been developed. The method includes operating one printhead to eject ink drops with a large size to form high density segments of the image, and operating a second printhead to eject ink drops with a small size to form low density segments of the image. The large ink drops provide high coverage in the high density segments, and the small ink drops provide improved image quality in the low density segments of the image.

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 enables the positions of inoperable inkjets in printheads to be corrected for positional changes arising from shifts in media, shrinkage of the media, thermal expansion of optical sensors that detect the inoperable inkjets, and other measurement errors. The measurement errors are detected with reference to image data corresponding to a reference pattern printed within a portion of a print job. Thus, reference marks do not need to be printed in areas outside of a print job as previously required.

Abstract: A method enables the positions of inoperable inkjets in printheads to be corrected for positional changes arising from shifts in media, shrinkage of the media, thermal expansion of optical sensors that detect the inoperable inkjets, and other measurement errors. The measurement errors are detected with reference to image data corresponding to a reference pattern printed within a portion of a print job. Thus, reference marks do not need to be printed in areas outside of a print job as previously required.

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 scratch-off document may include a substrate bearing a toner image and a scratch-off layer covering the printed content. The scratch-off layer may include a mass of a first solid ink and a mass of a second solid ink printed over the first solid ink in a distraction pattern. The toner image is formed of a toner that adheres to the substrate, while the scratch-off layer is made of a wax-based or other solid ink that may be removed from the substrate by scratching without removing the toner image. The distraction pattern includes varying pile heights that distract a viewer from any pile height variations that may exist in the toner image.

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 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 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.