A liquid discharge apparatus includes a head, a driver, and circuitry. The head has multiple nozzles and discharges a liquid from each of multiple nozzles to an object in a flight direction to form a film on a surface of the object. The driver moves at least one of the head or the object relative to other of the head or the object. The circuitry determines an amount of the liquid discharged from each of the multiple nozzles based on a flight angle between the flight direction and a normal direction of the surface of the object for each of the multiple nozzles and causes the head to discharge the liquid from each of the multiple nozzles for the amount of the liquid determined for each of the multiple nozzles.

A system and method for testing printheads is disclosed. The system comprises an optical sensor mounted on a movable carriage. The optical sensor is moved past a nozzle to be tested on the printhead while the nozzle ejects ink. The output signal of the optical sensor can be used to determine when the trajectory of the ejected ink is improper.

A liquid discharging apparatus includes a discharging unit that includes a nozzle row that discharges a liquid, and that is able to reciprocate in a first direction that intersects the nozzle row; a transport unit that transports a medium in a second direction that intersects the first direction; and a reading unit that reads the liquid discharged from the discharging unit to the medium. The liquid discharging apparatus is configured to execute an adjustment pattern forming operation for forming a first adjustment pattern for adjusting a landing position of the liquid discharged from the discharging unit in the first direction and a second adjustment pattern for adjusting the landing position of the liquid discharged from the discharging unit in the second direction on the medium, and an adjustment pattern reading operation for reading the first and second adjustment pattern with the reading unit according to a single command.

Systems for forming three-dimensional marking material images on moving substrates include a print head arranged about a media path by which the substrate passes the print head at a predetermined media velocity. The jets marking material at a predetermined velocity onto the substrate surface to form a three-dimensional marking material image. A firing time of forming a first layer of marking material may be different with respect to a print run start time than a firing time for ejecting marking material for forming successive layers. The firing time may be adjusted by advancing or delaying the firing time with respect to an initial firing time for forming the first layer. The advance or delay may be calculated by a processor, and the calculation may be fed to a time advance/delay buffer contained by the print head.

A method for controlling drop collisions in a drop on demand printing apparatus, comprising discharging a first drop (101) from a first dispenser (111) to move along a first path (103) and discharging a second drop (102) from a second dispenser (112) to move along a second path (104) that crosses with the first path such that the drops are expected to collide and form a combined drop (105), characterized by: measuring the collision of the drops (101, 102); examining whether the collision was effected as expected; if the collision was not effected as expected, altering the parameters of dispensing of the drops (101, 102) from the dispensers (111, 112).

A liquid droplet ejecting apparatus includes: an ejecting head made of metal and having an ejection surface; an electrode which moves relative to the ejection surface; a voltage source generating a potential difference between the ejecting head and the electrode; an electric current detector detecting an electric current between the ejecting head and the electrode; and a controller. The controller is configured to: calculate a flying speed of the liquid droplet based on a first distance between the ejecting head and the electrode and a time during which the electric current flows between the ejecting head and the electrode; and calculate an ejection bending amount, based on a time after the liquid droplet is ejected from the ejecting head in a state that the ejection surface and the electrode are apart from each other by a second distance and until the liquid droplet lands on the electrode.

In a method for printing a digital image in swaths with a swath time corresponding to the width of the digital image on the image receiving medium in the main scanning direction, the print controller issues a trigger that a spitting action for at least part of the printing elements of the print head needs to be performed. A swath time of subsequent swaths is gradually increased until the print head reaches a maintenance tray at a side of the print surface. The print head stays at the maintenance tray until air between the print head and the maintenance tray has approximately reached a standstill. Then, at least part of the printing elements of the print head are spitting marking material in the maintenance tray. After the spitting, the swath time of subsequent swaths is gradually decreased until the swath time is corresponding again with the width of the digital image on the image receiving medium in the main scanning direction. A digital inkjet printer is configured to perform the method.

There is provided a liquid droplet ejecting apparatus including: a conveyor configured to convey a print medium in a conveying direction; a line head having a plurality of nozzles which is disposed side by side in the conveying direction and a crossing direction crossing the conveying direction and each of which is configured to eject a liquid droplet to the print medium; and a controller configured to increase an ejection velocity of the liquid droplet by an upstream nozzle, of the plurality of nozzles, located upstream in the conveying direction of a downstream nozzle being a part of the plurality of nozzles, to be higher than the ejection velocity of the liquid droplet by the downstream nozzle, or to delay an ejection timing of the liquid droplet by the upstream nozzle.

A method of printing using drop-on-demand collision of multiple liquid drops, the method including: discharging a first liquid drop from a first dispenser and a second liquid drop from a second dispenser so that the first and second liquid drops coalesce in flight and form a combined drop; measuring, via at least one sensor, at least one flight parameter of the combined drop while the combined drop is in flight; comparing the measured flight parameter to a target criterion; and based on the comparison, automatically adjusting at least one discharge parameter for at least one of the first dispenser or the second dispenser before a subsequent discharge, wherein the method is performed in a printing apparatus configured to deposit the combined drop onto a substrate to form part of a printed structure.

Described herein are bioprinters comprising: one or more printer heads, wherein a printer head comprises a means for receiving and holding at least one cartridge, and wherein said cartridge comprises contents selected from one or more of: bio-ink and support material; a means for calibrating the position of at least one cartridge; and a means for dispensing the contents of at least one cartridge. Further described herein are methods for fabricating a tissue construct, comprising: a computer module receiving input of a visual representation of a desired tissue construct; a computer module generating a series of commands, wherein the commands are based on the visual representation and are readable by a bioprinter; a computer module providing the series of commands to a bioprinter; and the bioprinter depositing bio-ink and support material according to the commands to form a construct with a defined geometry.