The present disclosure relates particularly but not exclusive to a method for printing in a multipass print mode using a first printhead (PT1) and a second printhead (PT2), the method including printing in a first pass a first image in a first area of a print medium using a first set (ST21) of nozzles (N5-N24) from the first printhead (PT1), printing in a second pass a coating layer over the first image using a second set (ST22) of nozzles (P4-P22) from the second printhead (PT2), and printing in a third pass a second image over the coating layer using a third set (ST23) of nozzles (N1-20) from the first printhead (PT1).

An ink printing process employs per-nozzle droplet volume measurement and processing software that plans droplet combinations to reach specific aggregate ink fills per target region, guaranteeing compliance with minimum and maximum ink fills set by specification. In various embodiments, different droplet combinations are produced through different print head/substrate scan offsets, offsets between print heads, the use of different nozzle drive waveforms, and/or other techniques. Optionally, patterns of fill variation can be introduced so as to mitigate observable line effects in a finished display device. The disclosed techniques have many other possible applications.

The present invention relates to a method of printing a print job by an image reproduction system. The print job specifies a printing step on an image receiving medium and a finishing step in or on the image receiving medium. The method comprises the steps of receiving the print job by the image reproduction system and receiving a trigger by a controller of the image reproduction system that the finishing step is not to be performed. In such a case for a digital image comprised in print job data of the print job, at least one digital finishing visualization image of a predetermined visual appearance of a result of the finishing step in or on the image receiving medium is obtained as well as a position of the digital image for merging the obtained at least one digital finishing visualization image with the digital image. The digital image is updated by merging the obtained at least one digital finishing visualization image with the digital image at the obtained position. The updated digital image is printed by the image reproduction system.

An inkjet printing apparatus includes: a print bar unit having a print bar, a maintainer, and a movement driver; and a controller. Upon maintenance of an inkjet head of the print bar, the controller is configured to drive the movement driver to move the maintainer from a deployment position to a retreat position with the print bar arranged at a maintenance position above a height position for printing while wiping a nozzle surface of the inkjet head with the wiper of the maintainer being moved. The deployment position is a position under the inkjet head in maintenance of the inkjet head and the retreat position is a position where the maintainer is retreated from the deployment position.

A method for detecting printing nozzle errors in an inkjet printing machine provides a high degree of robustness in the detection of errors by printing a nozzle test pattern in the inkjet printing machine. The test pattern is then digitalized by using a camera and transmitted to a computer for evaluation. There, the recorded test pattern is investigated by using methods of digital image processing, such as a Fourier analysis, and evaluated in the frequency range with regard to specific anticipated printing nozzle errors. Specific printing nozzle errors can be detected especially on the basis of amplitude, phase and variance errors in the signal in the frequency range. Moreover, by using the phase error, it is possible to evaluate whether the two print heads are disposed in an incorrect adjustment position relative to one another by calculating displacements of the phase error in transition regions of two print heads.

Disclosed is an industrial single-pass inkjet printer/press incorporating an line-scan camera. The line-scan camera enables system software to inspect every sheet for quality assurance purposes. These inspection results are tied back to a digital printer to take one or more of several possible actions. Actions include ensuring a particular number of acceptable prints are generated and sorted. Actions further include performing nozzle checks without pausing or interrupting production orders.

In a printing apparatus, an indefinite area in which slits are not formed is configured in a portion of a linear encoder scale in a rotation direction, and an adjustment unit, adjusts the timing of discharge from a printhead with respect to a first printing area out of a plurality of printing areas on a rotating member, without using a detection result of a first encoder sensor, based on a detection result of a second encoder sensor, the first encoder sensor being provided at a position corresponding to the indefinite area during a discharge of printing material with respect to the first printing, and the second encoder sensor being provided at a position that does not correspond to the indefinite area during the discharge of the printing material with respect to the first printing area.

Provided are a printing device and a print element substrate having a detection element row provided in correspondence to an ejection port row and capable of suppressing an increase in a length in an ejection port row direction. For that purpose, a row selection circuit 117 is provided in a detection element circuit 108, and a row of the detection element circuit is selected by row selection signals A0 and A1 transmitted through a common wiring.

In accordance with an embodiment, an inkjet head comprises a pressure chamber, an actuator and a control section. The pressure chamber houses ink. The actuator is driven to expand or contract the volume of the pressure chamber in order to eject the ink from an opening of the pressure chamber. The control section applies an expansion pulse of which the width is 0.4 times-0.9 times as large as an AT which is half a natural vibration period during which nozzle negative pressure is changed in the pressure chamber and which expands the pressure chamber to the actuator, and applies a contraction pulse which contracts the pressure chamber to the actuator.

A measurement method of nozzle overlapping width, in a main scanning direction intersecting a conveying direction of a recording medium, in an inkjet recording apparatus including a plurality of heads each having a plurality of nozzles that eject ink, includes a first step (S120), a second step (S130), and a third step (S140). The first step (S120) includes forming an image for measurement on the recording medium, using image data including combination patterns of droplet sizes, different with respect to each of blocks extending along the main scanning direction. The second step (S130) includes selecting the block having uniform density along the main scanning direction, in the image for measurement. The third step (S140) includes determining the nozzle overlapping width using a droplet size ratio adopted to form the image for measurement, on a basis of a position of the selected block.