A recording method for performing recording on a medium by forming dots by ejecting a liquid from nozzles during scanning. The recording method includes detecting an abnormal nozzle; disposing a normal nozzle in a row where dot missing occurs due to the abnormal nozzle by moving a medium by a first moving amount; performing first complementary recording in which at least a part of a dot missing region is complemented by a first dot which is recorded by the normal nozzle during the scanning; moving the medium by a second moving amount; and performing second complementary recording in which a second dot of which a size is greater than a size of a dot determined based on printing data is recorded on a row adjacent to a row of the abnormal nozzle by the normal nozzle that is positioned adjacent to the abnormal nozzle during the scanning.

The present disclosure relates to a printhead control system for a printer, wherein the printer includes at least one printhead comprising a plurality of nozzles for ejecting printing fluid, wherein the nozzles include high drop weight nozzles and low drop weight nozzles ejecting drops of different drop weight, and are each arranged to eject printing fluid on a print medium such as to print images in frame areas of the print medium and such as to clean nozzles in spit bar areas of the print medium; the printer further includes a transport unit for moving the print medium relative to the printhead, wherein the print medium includes frame areas for printing images and spit bar areas for cleaning the nozzles; the printhead control device including: a module to determine a first group of said nozzles located over a frame area of the print medium and a second group of said nozzles located over a spit bar area of the print medium; a module to operate the high drop weight nozzles of the first group such as to eject printing fluid and print an image in the frame area; a module to operate disable the low drop weight nozzles of the first group such as to not eject printing fluid in the frame area; and a module to operate the high drop weight nozzles and the low drop weight nozzles of the second group such as to alternately eject printing fluid in the spit bar area.

In a method and device for ascertaining print data for a print image to be printed, the print data is adapted and/or determined such that the time curve of the ink flow quantity, exhibits no quantity changes or flow rates due to which ink ejection errors might be produced, in particular nozzle failures. The device includes: a communication interface configured to receive the print data; and processing circuitry that ascertains, based on the print data, a time curve of an ink flow quantity of ink that, during the printing of the print image, flows in the print bar and/or is ejected from the one or more nozzles of the print bar; and determine, based on the time curve of the ink flow quantity, whether an ink ejection error will be produced.

A method of operating a printer analyzes a printed test pattern in a low-contrast printing configuration. The method includes forming a printed test pattern having a plurality of rows of negative marks on an image receiving member, each negative mark in the plurality of rows of negative marks being surrounded by ink from at least a portion of the plurality of inkjets. The method further includes generating scanned image data of the test pattern and identifying a plurality of locations in the cross-process direction for the negative marks in at least one row of negative marks in the scanned image data of the test pattern.

A liquid discharge apparatus to apply liquid to an application surface includes a head and processing circuitry. The head applies the liquid discharged from a nozzle to the application surface. The processing circuitry outputs abnormal discharge information of the nozzle. The abnormal discharge information is detected based on a shape of the liquid applied to the application surface.

A printer includes an ejecting head, and a printing control section, in which the ejecting head ejects ink onto the sheet while performing scanning of a plurality of times with respect to a predetermined raster line which extends in the scanning direction. In addition, the printing control section sets a nozzle use rate of a first complementing nozzle which is higher than a nozzle use rate in normal operation as a nozzle use rate of a complementing nozzle which ejects ink to a pixel to which a defective nozzle should eject ink on the sheet, instead of the defective nozzle, when the defective nozzle is detected, and sets a nozzle use rate of a second complementing nozzle which is lower than that of the first complementing nozzle as a nozzle use rate of a supplementary complementing nozzle which is the peripheral nozzle of the complementing nozzle.

A printing apparatus includes a transport unit, a printing head, and a control unit that prints, on a printing medium, a test pattern for inspecting a state of ink discharge by a nozzles. The test pattern includes a first pattern element group in which a plurality of pattern elements to be printed by the nozzles are arranged in the transport direction, and a second pattern element group in which a plurality of pattern elements to be printed by the nozzles are arranged in the transport direction. After the control unit causes the transport unit to transport, by a distance equal to or greater than a nozzle pitch, the printing medium printed with the first pattern element group by causing the nozzles to discharge the ink, the control unit prints the second pattern element group on the printing medium by causing the nozzles used to print the first pattern element group to discharge the ink.

A three dimensional printer is configured to move at least one printhead from an area where the printhead is forming an object to a position opposite a shaft. The at least one printhead is operated to eject material onto the shaft and the shaft is rotated to enable a light sensor to generate signals indicative of a height of material at a plurality of positions on the shaft. The signals are compared to an expected height of material at each position to identify inoperative inkjets in the at least one printhead.

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.