A liquid discharge apparatus includes a liquid discharge head configured to discharge a liquid and a circuitry configured to drive the liquid discharge head. The liquid discharge head includes multiple nozzles from each of which the liquid is dischargeable, multiple valves configured to openably close the multiple nozzles, respectively, and multiple drivers configured to respectively drive the multiple valves, and the circuitry controls a voltage to be applied to the multiple drivers according to a number of driven valves of the multiple valves to be simultaneously driven.

A recording condition determining method is executed by a recording device performing recording by a main scanning and a sub scanning. The method includes a patch recording step of recording patches onto a recording medium by the overlap-processing in which the main scanning is performed on a partial region of the recording medium in an overlapping manner a plurality of times, the patch recording step including recording the patches at a plurality of different positions in a main scanning direction by a plurality of types of the overlap-processing under respectively different recording conditions. The method further includes a selection accepting step of accepting selection of a patch from among a plurality of the recorded patches, and a determination step of determining, as the recording condition of the overlap-processing of an actual recording, the recording condition of the overlap-processing associated with the patch selected in the selection accepting step.

In a method of controlling a liquid ejecting apparatus, where the liquid ejecting apparatus includes a pressure chamber that communicates with a nozzle that ejects a liquid, a drive element that changes a pressure of the liquid in the pressure chamber, and a drive circuit that supplies the drive element with an ejection pulse that generates a change in the pressure that ejects the liquid from the nozzle, the method includes specifying a viscosity of the liquid in the nozzle and a surface tension of the liquid in the nozzle from a residual vibration when the pressure of the liquid in the pressure chamber is changed, and controlling a waveform of the ejection pulse according to the viscosity and the surface tension.

A digital printing system includes a print head and a processor. The print head is configured to jet droplets of ink. The a processor is further configured to translate a required shade of a color, to be printed at a given location on a substrate by the print head, into a sequence of pulses, the sequence including: (a) up to a predefined maximum number of driving pulses that cause the print head to jet respective droplets, and (b) a tickling pulse, which has a smaller amplitude than the driving pulses and which causes the print head to jet a droplet smaller than the droplets jetted in response to the driving pulses. The processor is additionally configured to apply the sequence of pulses to the print head.

A digital printing system (10) includes a print head (622) and a processor (20). The print head is configured to jet droplets of ink. The processor is further configured to translate a required shade of a color, to be printed at a given location on a substrate by tire print head, into a sequence of pulses (625, 630), the sequence including: (a) up to a predefined maximum number of driving pulses (625) that cause the print head to jet respective droplets, and (b) a tickling pulse (630), which has a smaller amplitude than the driving pulses and which causes the print head to jet a droplet smaller than the droplets jetted in response to the driving pulses. The processor is additionally configured to apply the sequence of pulses to the print head.

A method of driving an inkjet head having a nozzle and a pressure generator, a plurality of droplets of the ink discharged in response to a series of the drive signals being caused to hit a recording medium to form a single pixel. The method includes, applying, to the pressure generator, the series of the drive signals including a first one of the drive signals that has a first voltage amplitude and a second one of the drive signals that has a second voltage amplitude larger than the first voltage amplitude. A last drive signal in the series of the drive signals is the second one of the drive signals. The first voltage amplitude and the second voltage amplitude are determined such that a ratio of (first voltage amplitude)/(second voltage amplitude) has a value corresponding to a specific gravity of the ink to be discharged.

A droplet discharge apparatus includes a discharge device, a plurality of waveform generation units, a plurality of correction units, and a drive unit. The discharge device discharges droplets of a plurality of droplet types according to a plurality of drive waveforms. The plurality of waveform generation units individually generate drive waveforms used to discharge each of the plurality of droplet types. The plurality of correction units individually correct the drive waveforms generated by each of the plurality of waveform generation units, using correction magnifications different corresponding to the drive waveforms generated by the plurality of waveform generation units, to generate correction waveforms. The drive unit causes the discharge device to discharge the droplets according to corrected drive waveforms generated by individually switching the drive waveform corresponding to the plurality of droplet types to the correction waveforms.

A head driving device includes a recording head, an input-and-output interface, and circuitry. The recording head includes a plurality of nozzles and a plurality of pressure generating elements corresponding to the plurality of nozzles. The input-and-output interface is configured to acquire correction information generated based on a chart image of a specific pattern for correcting a deviation amount of a landing position of each of the plurality of nozzles. The circuitry is configured to set the correction information acquired by the input-and-output interface and perform correction processing for correcting the deviation amount of the landing position on a driver for each of the plurality of nozzles of the recording head, in accordance with the correction information.

There is provided a head driving device for causing a head to discharge droplets. The device includes a drive circuit, a first drive waveform generation circuit, a second drive waveform generation circuit, and a correction circuit. The drive circuit is configured to drive the head based on a plurality of drive waveforms to discharge the droplets. The first drive waveform generation circuit configured to generate a first drive waveform of the plurality of drive waveforms. The second drive waveform generation circuit is configured to generate a second drive waveform of the plurality of drive waveforms. The correction circuit is configured to correct the first drive waveform and the second drive waveform with reference to an intermediate potential.

First and second individual flow paths coupling a first common liquid chamber to a second common liquid chamber are arranged side by side, and each individual flow path is provided with first and second pressure chambers. At least a part of the first individual flow path is provided in a space overlapping a region between the adjacent second pressure chambers when viewed in a Z axis direction, the space not overlapping the second pressure chamber when viewed in a Y axis direction.