A liquid discharge apparatus includes a head having multiple nozzles arrayed in a nozzle array direction, a conveyor configured to convey a linear medium in a conveyance direction, circuitry configured to control the head to discharge a liquid droplet to the linear medium from the multiple nozzles based on image data, and a droplet detector configured to detect the liquid droplet discharged from the multiple nozzles. The circuitry is further configured to select discharge nozzles, from the multiple nozzles, used to discharge the liquid droplet to the linear medium according to a detection result of the droplet detector, and correct the image data according to the discharge nozzles selected by the circuitry.

A printing apparatus configured to perform printing by a combination of transport of a printing medium by a transport unit and main scanning for discharging ink in association with movement of a scanning unit, wherein the control unit is configured to calculate, a one-time transport amount by the transport unit for each nozzle row at each of the nozzle row positions, the one-time transport amount being a complementary transport amount at which non-discharge of ink by the defective nozzle is complementable by discharge of ink by the normal nozzle, based on a relationship between the main scanning before the transport and the main scanning after the transport, determine a common transport amount to the nozzle rows at the respective nozzle row positions based on the complementary transport amount for each nozzle row, and perform the printing the determined common transport amount as the one-time transport amount by the transport unit.

A printing system is disclosed. The printing system includes at least one physical memory device to store calibration logic and one or more processors coupled with the at least one physical memory device to execute the calibration logic to generate a uniformity compensated halftone design for each of a plurality of pel forming elements, generate a missing neighbor corrected halftone design for each of the pel forming elements, generate a missing neighbor threshold lowering function for each of the pel forming elements based on the uniformity compensated halftone designs and the missing neighbor corrected halftone design and compute an average of the missing neighbor threshold lowering functions to generate an average missing neighbor threshold lowering function.

A printing system is disclosed. The printing system includes at least one physical memory device to store uniformity compensation logic and one or more processors coupled with the at least one physical memory device to execute the uniformity compensation logic to receive print image measurement data corresponding with each of a plurality of pel forming elements, generate a first set of intermediate images based on the print image measurement data, determine whether historical sets of intermediate images are available, generate first transfer functions corresponding to each of the pel forming elements based on the first set of intermediate images and the historical sets of intermediate images upon a determination that the historical sets of intermediate images are available and transmit the first transfer functions for each of the pel forming elements.

A printing apparatus includes a medium accommodation portion that accommodates a medium, a medium discharge port for discharging the medium to an outside of the printing apparatus, a medium transport section that transports the medium along a transport path from the medium accommodation portion toward the medium discharge port, an ejection head that ejects a liquid to the medium to form an image on the medium, a heat generation section that dries the liquid ejected to the medium by heat, and an image detection section that detects the image formed on the medium. The ejection head, the heat generation section, and the image detection section are provided along the transport path. The ejection head is located between the heat generation section and the image detection section in a direction along the transport path.

Means and methods for dispensing small amounts of liquid from multi-channel microdispensing devices, suitable for use in automatic processing in biological assays and for the cultivation of cells and tissues, by means of optical control of the dosed liquid by specific light barrier units.

A compensation method and a device for nozzle abnormality, and a printer are provided. The method includes determining position information of an abnormal nozzle of an inkjet head (S100); acquiring printing parameters, determining first data corresponding to the abnormal nozzle, and based on the position information of the abnormal nozzle and the printing parameters, determining position information of a compensation nozzle for compensating the first data corresponding to the abnormal nozzle (S200); and based on the printing parameters, acquiring second data of the compensation nozzle in a normal printing state which includes ink out data and ink holding data, determining an address of the ink holding data, and generating compensation data by writing the first data into the address of the ink holding data (S300).

A printing carriage comprises a printhead, and two sensors for scanning an image deposited on a print media by the printhead. The sensors are provided on opposite sides of the printhead in a direction of movement of the printhead so that, during a printing pass of the printhead on the print media, one sensor is positioned on a trailing side of the moving printhead.

A method for detecting and compensating for defective printing nozzles in an inkjet printing machine includes printing test sheets each including at least one printing nozzle test chart and at least one gray area for every color separation. The test sheets are recorded and digitized with subsequent pixel-nozzle mapping and amplitude/phase value determination by using a computer. Current measurements are taken at the printing nozzles in between test sheets and customer sheets while being printed. The computer is used for teaching in a SVM model with the results of the current measurement and pixel-nozzle mapping and amplitude/phase determination. The taught-in SVM model and the current measurements are applied to printed, recorded and digitized customer's images to detect defective printing nozzles during production printing on the inkjet printing machine and the detected defective printing nozzles are compensated for.

An example of an apparatus is provided. The apparatus includes a printhead to dispense drops of print fluid on a media. The drops are to travel along a drop path through air from the printhead. In addition, the apparatus includes a light source to emit light across the drop path. The apparatus also includes a detector to detect an intensity of the light received from the light source. The drop path is to intersect an optical path from the light source to the detector. Furthermore, the apparatus includes a coating disposed on the optical path between the drop path and the detector. The coating is to absorb a threshold amount of the light.