Abstract: An MFD is disclosed. For example, the MFD includes a printhead to dispense print material, an enhancement printhead to dispense an enhancement printing fluid, a processor and a non-transitory computer-readable medium storing a plurality of instructions. The instructions when executed by the processor cause the processor to perform operations that include determining that an automated enhancement feature was selected, analyzing each pixel of an image to be printed to determine one or more pixels that are to receive the enhancement printing fluid, controlling the printhead to print the image, and controlling the enhancement printhead to dispense the enhancement printing fluid on the one or more pixels that are to receive the enhancement printing fluid.

Abstract: A method includes ejecting a plurality of drops of a build material from a nozzle of a 3D printer. The build material cools and solidifies after being ejected to form a 3D object. The method also includes controlling an oxidation of the drops, the 3D object or both to create different oxidation levels in first and second portions of the 3D object.

Abstract: A printing system and method of inspecting drop ejection in a printing system is disclosed. The method includes capturing an image of each of a plurality of drops of a print material after ejection from an ejector of a printing system, creating a temporally averaged image from each image of the plurality of drops of print material, and classifying one of the plurality of drops of print material based on the temporally averaged image that was created. The use of a pretrained convolutional neural network for classifying one of the plurality of drops and comparing the temporally averaged image to another temporally averaged image to classify one of the plurality of drops may be employed. The printing system also includes a camera with a high-speed shutter where the shutter is synchronized to an ejector pulse, and a video analytic framework coupled to the ejector and the camera configured to generate a jetting result for each of the one or more drops of liquid print material.

Abstract: Ink-based digital printing systems useful for ink printing include a rotatable charge-retentive reimageable surface layer configured to receive a layer of fountain solution. The fountain solution is carried to the charge retentive surface by a fog or mist including fountain solution aerosol particles, dispersed gas particles, and charge directors that impart charge to the fountain solution aerosol particles. The charge-retentive reimageable surface may be charged to a uniform potential, and selectively discharged using an ROS according to image data to form an electrostatic latent image. The charged fountain solution adheres to portions of the charge-retentive reimageable surface according to the electrostatic latent image to form a fountain solution image thereon. The fountain solution image can be partially transferred to an imaging blanket, where the fountain solution image is inked. The resulting ink image may be transferred to a print substrate.

Abstract: An image based correction system compensates for the image quality artifacts induced by thermal ghosting on evolving imaging member surfaces. With thermal ghosting directly tied to previous image content, a feed forward system determines thermal ghosting artifacts based on images previously rendered and generates an open loop gray-level correction to a current image that mitigates undesirable ghosting. For example, the correction system compensates for the thermal ghosting by making the current image “lighter” in areas that will be imaged onto warmer blanket regions, thereby cancelling out TRC differences between different temperature regions. A temperature sensor is used to measure the temperature of the imaging blanket due to the stresses induced by the image. This data is used to learn the parameters of the temperature model periodically during operation, and used in subsequent corrections to mitigate thermal ghosting in spite of changes in blanket properties over use and time.

Abstract: A printing system comprises an ink deposition assembly and a media transport device. The ink deposition assembly comprises printheads to deposit a print fluid, such as ink, on print media, such as paper. The media transport device holds the print media against a movable support surface, such as a belt, by vacuum suction platen and transports the print media though a deposition region. The vacuum suction is communicated to the movable through platen holes and platen channels in a vacuum platen. At least some of the platen channels have a high impedance region that has a reduced open cross-sectional area as compared to another region of the platen channel.

Abstract: A color inkjet printer includes an electrode that emits an electric field into a gap between a printhead and a media transport that carries media past the printhead. Image data generated by an optical sensor after an ink image is printed on the media is analyzed to measure at least one image quality metric. When the measured image quality metric is outside of a tolerance range, the voltage of a voltage source electrically connected to the electrode is adjusted to improve the wetting of the media type with the ink ejected by the printhead.

Abstract: A method of inkjet printer operation identifies a problem with an inkjet printer using a comparison of an index for a printhead map identifying inoperative inkjets in a printhead with indexes for clusters of extracted feature descriptors corresponding to printhead maps for printheads having inoperative inkjets stored in a dictionary in a database operatively connected to a controller in the inkjet printer. The dictionary is developed using unsupervised cluster analysis of datasets comprised of printhead maps identifying inoperative inkjets in a plurality of printheads.

Abstract: A method of inkjet printer operation indicates a need for a remedial printhead operation by predicting a number of inoperative inkjets and locations for the inoperative inkjets in at least one printhead in the inkjet printer at a predetermined time. The prediction is made using Markov chain Monte Carlo models that correspond to different ranges of area coverage density for inkjet areas of a printhead.

Abstract: A printing system comprises a print fluid deposition assembly, a media transport device, and an air flow control system. The print fluid deposition assembly comprises a carrier plate and a printhead arranged to eject a print fluid through an opening of the carrier plate to a deposition region. The media transport device holds a print medium against the movable support surface by vacuum suction and transports the print medium through the deposition region. The air flow control system comprises an air supply unit comprising air flow guide structure extending into the opening of the carrier plate between the carrier plate and the printhead to flow air through the opening. The air flow control system controls the air supply unit to selectively flow the air based on a location of a print medium relative to the printhead.

Abstract: A method of operating a printer extends the print zone of the printer by separating at least two printhead modules in the print zone by a distance that is greater than a width of a printhead module. The printhead modules are operated to print multiple color separations of an ink image and operates an optical sensors generates image data of the printed multiple color separations. The image data of the printed color separations are used to adjust distances between printhead modules in the print zone.

Abstract: A printing system comprises an ink deposition assembly, a media transport device, and an airflow control system. The ink deposition assembly comprises a printhead to eject ink through a carrier plate opening in a carrier plate. The media transport device holds a print medium against a movable support surface by vacuum suction and transports the print media through a deposition region. The airflow control system comprises a baffle that is movable between an upstream-blocking configuration and a downstream-blocking configuration, and an actuator configured to move the baffle. In the upstream-blocking configuration the baffle blocks airflow through an upstream side of the printhead opening while allowing airflow through a downstream side of the printhead opening. In the downstream-blocking configuration the baffle blocks airflow through the downstream side of the printhead opening while allowing airflow through the upstream side of the printhead opening.

Abstract: An optical gloss meter above an imaging member surface measures fountain solution surface gloss on the imaging member surface in real-time during a printing operation. The measured gloss corresponds to a thickness of the fountain solution layer and may be used in a feedback loop to actively control fountain solution layer thickness by adjusting the volumetric feed rate of fountain solution added onto the imaging member surface during a printing operation to reach a desired uniform thickness for the printing. This fountain solution monitoring system may be fully automated.

Abstract: Ink-based digital printing systems useful for ink printing include a secondary roller having a rotatable reimageable surface layer configured to receive fountain solution. The fountain solution layer is patterned on the secondary roller and then partially transferred to an imaging blanket, where the fountain solution image is inked. The resulting ink image may be transferred to a print substrate. To achieve a very high-resolution (e.g., 1200-dpi, over 900-dpi) print with these secondary roller configurations, an equivalent very high-resolution fountain solution image needs to be transferred from the secondary roller onto the imaging blanket. To increase the resolution of the image on the secondary roller, examples include a textured surface layer added to the secondary roller for contact angle pinning the fountain solution on the roll. Approaches to introduce a micro-structure onto the surface layer of the secondary roller, and also superoleophobic surface coatings are described.

Abstract: Apparatus and method for using a line laser (LL) to quickly mark a substrate or media by utilizing a laser additive on/within the substrate/media, which greatly reduces the power requirement for marking the substrate/media. The combination of the LL wide swath (>305 mm) and the improved media/surface sensitivity to laser wavelength allows the LL marking system to achieve faster marking than other systems. The LL is mounted over a transport which transports the sensitized substrate/media past the LL for marking. The desired image is projected from the LL line by line in synch with the moving media and once the media passes the beam path of the LL, marking is complete. In this case, the media has been physically-altered via the heat generated by the LL interacting with the photosensitized media and is permanent. A second method would use a photosensitizing agent coated on top of the media to be marked.

Abstract: A method of operating a printer separates the image content data for a sheet in a print job into multiple color separations and operates a digital air curtain between the printhead modules that print the multiple color separations. Image data of the printed color separations are used to adjust operating parameters for the digital air curtain.

Abstract: A printer having a pump which includes an inner cavity which retains a liquid metal printing material, and a nozzle, where the nozzle is configured to eject a plurality of liquid metal drops, an actuation coil configured to supply a pulse to the liquid metal to generate an electromagnetic force upon the liquid metal, where the actuation coil supplies a pulse at a first time varying current pulse, where the electromagnetic force causes the nozzle to eject a drop of liquid metal. The actuation coil also supplies a pulse at a second time varying current pulse, where the electromagnetic force is not sufficient to eject a drop of liquid. A method for metal jetting in a printer is also disclosed where differences between the temperature in an upper portion of the pump and the temperature in a lower portion of the pump are minimized.

Abstract: A color inkjet printer includes an electrode that emits an electric field into a gap between a printhead and a media transport that carries media past the printhead. Image data generated by an optical sensor after an ink image is printed on the media is analyzed to measure at least one image quality metric. When the measured image quality metric is outside of a tolerance range, the voltage of a voltage source electrically connected to the electrode is adjusted to improve the wetting of the media type with the ink ejected by the printhead.

Abstract: A printing system comprises a print fluid deposition assembly, a media transport device, and an air flow control system. The print fluid deposition assembly comprises a carrier plate and a printhead arranged to eject a print fluid through an opening of the carrier plate to a deposition region. The media transport device comprises a movable support surface to transport a print medium along a process direction through the deposition region, the media transport device holding the print medium against the movable support surface by vacuum suction. The air flow control system is arranged to selectively flow air through the opening of the carrier plate between the carrier plate and the printhead based on a location of a print medium transported by the media transport device relative to the printhead.

Abstract: A method includes ejecting a plurality of drops of a build material from a nozzle of a 3D printer. The build material cools and solidifies after being ejected to form a 3D object. The method also includes controlling an oxidation of the drops, the 3D object or both to create different oxidation levels in first and second portions of the 3D object.