Examples relate to computer-implemented methods for a printing system comprising a printhead, and to printing systems. A method for a printing system comprises retrieving a stored first offset applied to the printhead to align the printhead, the first offset determined based on a first user input signal; and further aligning the printhead according to a further offset determined based on a further user input signal, the further offset indicating a difference from the first offset.

A printing device comprising a printing head including a plurality of nozzles configured to discharge ink to a printing medium are arranged, and a control unit configured to control discharge of the ink. The printing head is configured to discharge the ink along with scanning that is a relative movement in a predetermined direction with respect to the printing medium, and in test printing for printing a TP on the printing medium, the control unit performs control such that the ink of a first discharge amount is discharged from the nozzles when a color difference between the TP and the printing medium is greater than a predetermined threshold value, and the ink of a second discharge amount that is greater than the first discharge amount is discharged when the color difference between the TP and the printing medium is equal to or smaller than the threshold value.

A discharge position adjusting method includes: moving a first nozzle row and a second nozzle row in scanning directions, each of the first and second nozzle rows having a plurality of nozzles that eject liquid droplets, the first and second nozzle rows being disposed at different locations in a predetermined direction, the scanning directions intersecting the predetermined direction; forming a first image by ejecting liquid droplets from the first nozzle row, and forming a second image by ejecting liquid droplets from the second nozzle row; and adjusting positions at which liquid droplets are to be placed by using the first and second images. The first and second images are created during the moving of the first and second nozzle rows.

An information processing device performs processing of specifying a positional relationship between a first printing section and a second printing section based on image capturing data of a test image that is printed on a printing medium by the first printing section and the second printing section in each of which a plurality of printing elements are arranged. The test image includes a plurality of first lines which are printed by the first printing section so as to have printing positions different from each other in a line arrangement direction on the printing medium and a plurality of second lines which are printed by the second printing section so as to have printing positions different from each other in the line arrangement direction. The information processing device contains a printing coordinate acquisition section, a printing position acquisition section, and a positional shift amount calculation section.

A method is provided that is implemented on a control device connected with an inkjet printer, which includes an inkjet head having an ink discharging surface, a head scanning unit reciprocating the inkjet head relative to a recording sheet along a scanning direction parallel to the ink discharging surface, and a wave shape generating mechanism deforming the recording sheet in a predetermined wave shape that has tops of portions protruding in a first direction toward the ink discharging surface and bottoms of portions recessed in a second direction opposite to the first direction alternately arranged along the scanning direction, the method including acquiring gap information related to a gap between the ink discharging surface and each individual one of the tops and the bottoms on the recording sheet, and determining whether the gap information acquired for each individual one of the tops and the bottoms is abnormal.

A distance measuring device includes: an imaging unit that captures a test pattern image including a pair of first markers and a second marker that is formed under a condition different from a condition applied to the first markers; a position detecting unit that detects a position of each of the pair of first markers and the second marker in a captured image captured by the imaging unit; a ratio calculating unit that calculates a ratio of a distance between the pair of the first markers in the captured image and an actual distance between the pair of the first markers; and an actual distance calculating unit that calculates an actual distance between one of the first markers as the pair and the second marker by multiplying a distance between the one of the first markers as the pair and the second marker in the captured image by the ratio.

Wherein, in the first dither mask, when the first space is cut by the first plane, a plurality of threshold values in the first plane has a blue noise characteristic in the spatial frequency domain, and when the first space is cut by a second plane extending in a direction different from that of the first plane, a plurality of threshold values in the second plane has a blue noise characteristic in the spatial frequency domain.

A liquid jet device includes a head that discharges liquid to an object; a moving mechanism that moves at least one of the object and the head; and a controller that causes the head to discharge the liquid while moving the at least one of the object and the head in a first direction to form a first row of dots, and causes the head to discharge the liquid while moving the at least one of the object and the head in a second direction opposite the first direction to form a second row of dots that overlaps the first row of dots. The controller causes the center of the first dot in the second row of dots to be shifted from the center of the last dot in the first row of dots by a distance greater than or equal to a distance d.

An ejection apparatus includes an ejection head having an ejection port, a droplet detection unit, an acquisition unit, a control unit, and a decision unit. The droplet detection unit detects that a droplet ejected from the ejection port has reached a predetermined position. The acquisition unit acquires information regarding a velocity of movement of the detected droplet. The control unit controls the ejection head to eject the droplet from the ejection port. The decision unit decides a number of consecutive ejections of a plurality of droplets from the ejection head based on the acquired information regarding the velocities of each of the plurality of droplets ejected consecutively and detected by the droplet detection unit. If the acquisition unit acquires the information regarding velocities of detected droplets, the control unit controls the ejection head to consecutively eject the droplets from the ejection head based on the decided number of consecutive ejections.

A method for determining a working gap includes a first recording step for ejecting ink from a recording head onto a first recording medium to record a test pattern, a first imaging step for capturing the test pattern recorded on the first recording medium in each of a state where a distance between the recording head and the first recording medium is a first distance, and a state where a distance between the recording head and the first recording medium is a second distance, a function calculating step, a second recording step for recording the test pattern on a second recording medium, a second imaging step for capturing the test pattern recorded on the second recording medium, and a working gap determining step for determining, based on the number of pixels of the captured test pattern and a function, a distance between the recording head and the second recording medium.