The ink jet printing system may have a printing section and a testing section. The ink jet printing system may include a first alignment mark disposed in the printing section along a first direction, a second alignment mark disposed in the testing section along a second direction perpendicular to the first direction, an ink jet head for providing chemical liquid onto a substrate, a first identification member proximate to the ink jet head, the first identification member identifying the first alignment mark and the second alignment mark, a gantry for moving the ink jet head between the printing section and the testing section, a second identification member proximate to the gantry, the second identification member identifying discharging points of the chemical liquid in the testing section, and a control member for correcting discharging points of the chemical liquid discharged from the ink jet head onto the substrate in the printing section based on a result that the second identification member identifies the discharging points of the chemical liquid in the testing section. The testing section may be arranged in substantially parallel with the printing section along the first direction.

A method for reducing artefacts in printed objects comprises receiving print data to be printed by a printhead arrangement, the printhead arrangement being movable in a print direction and comprising a plurality of printhead dies, wherein printhead dies adjacent to each other comprise an overlap area when viewed in the print direction. The print data to be printed are modified near and/or at the overlap areas between printhead dies of the printhead arrangement to compensate for drop placement.

A droplet deposition head including a datum surface arrangement for alignment of the head relative to an external mounting component in either a vertical mounting mode in which the head is held against a vertical mounting plate or a horizontal mounting mode where the head is held against a horizontal mounting plate. The datum surface arrangement comprising at least seven datum surfaces (x1; y1, y2, y3; z1, z2, z3) provided on the head, wherein five of the seven datum surfaces are provided for alignment in both vertical and horizontal mounting modes, and wherein a sixth datum surface (z3) is provided for alignment exclusively in said horizontal mounting mode and a seventh datum surface (y3) is provided for alignment exclusively in said vertical mounting mode.

According to examples, an apparatus may include a tracking sensor, a delivery device and a controller. The controller may receive an input indicative of the apparatus being aligned to an alignment location, determine, based on input from the tracking sensor, that the apparatus has moved a predefined distance or past the predefined distance in a first direction from the alignment location, and based on a determination that the apparatus has been moved the predefined distance or past the predefined distance, cause a first feedback to be outputted to instruct a user to move the apparatus in a second direction. The controller may also, as the apparatus is moved in the second direction, cause the delivery device to generate an image that has an intended justification with respect to the alignment location.

A liquid ejection apparatus includes a liquid ejection head, a sensor, a carriage, and a controller. The controller is configured to perform: setting a first sheet at a first printing position; printing an image on the first sheet while conveying the first sheet from the first printing position; determining whether an interval is more than a predetermined period; in a case where the interval is determined to be more than the predetermined period: causing the carriage to move in a first direction to a first detection position at which a second sheet is detected; and in response to detecting the second sheet, causing the carriage to move in the first direction to a first carriage position.

A printer includes an ink ejection unit configured to eject ink to a print medium, a transport belt on which the print medium is mounted, a driving section configured to transport the print medium by moving the transport belt, a specifying section configured to specify a print head to be adjusted using a test pattern, markers configured to indicate a position of the print medium when the test pattern is printed on the print medium, and a driving controller configured to control the driving section. The driving controller controls the driving section in accordance with the print head to be adjusted specified by the specifying section so as to adjust a position of the print medium.

Disclosed herein is a method of calibrating a printing device, a detector for use in a printing device and a printing device. The method is for calibrating a printing device having a nozzle that is to eject a drop of a printing fluid and a sensor that is to detect a drop of the printing fluid at a detection position. The method comprises ejecting a drop of the printing fluid from the nozzle; determining a measurement signal during a detection window with the sensor; extracting an arrival time of the drop from the measurement signal; and determining an adjusted detection window by adjusting the detection window based on the arrival time.

An ink discharge apparatus includes a discharge head and a controller, the discharge head having a plurality of nozzle rows arranged in a first direction, each of the plurality of nozzle rows including a plurality of nozzles arranged to align in a second direction intersecting the first direction. The controller is configured to receive a print job and carry out a mode determining process to determine whether a print mode is a low gap print mode or a high gap print mode based on the print job, and a number of discharge reducing process to reduce the total number of discharging ink per unit time from the plurality of nozzles as compared with the case of the low gap print mode, if the print mode is determined as the high gap print mode.

An image forming apparatus includes a recording head and processing circuitry. The recording head includes a plurality of nozzles. The processing circuitry prints a reference adjustment pattern on a recording medium using a reference nozzle, which is one of the nozzles. When the recording medium is conveyed from the reference nozzle in a sub-scanning direction by a predetermined conveyance amount, the processing circuitry prints an adjustment pattern on the recording medium using a designated nozzle, which is apart by a predetermined distance with respect to a nozzle apart from the reference nozzle in the sub scanning direction by the predetermined conveyance amount. The processing circuitry detects the reference adjustment pattern and the adjustment pattern, computes a distance between the reference adjustment pattern and the adjustment pattern in the sub-scanning direction, and determines whether a standard deviation of the distance computed is equal to or larger than a predetermined value.

A printing system and method print different colors onto a target object to form a machine-readable data representation having a symbol contrast of at least 40%. The printing system and method direct print heads to print the different colors by printing a base layer of a first color of the different colors on the target object and printing an upper layer of a different, second color of the different colors on top of the base layer of the first color, or by printing print the machine-readable data representation as an interdigitated data representation by printing the different colors onto the target object so that none of the different colors is printed on top of another color of the different colors.