There is provided a method for controlling driving of an inkjet head including recording elements each including a nozzle and a driving element. The method includes a pulse width setting step. In this step, when a predetermined number of ink droplets ejected according to the predetermined number of driving pulses are made to land in the same pixel range, the predetermined number of first driving pulses each having a pulse width longer than a reference pulse width and the predetermined number of second driving pulses each having a pulse width shorter than the reference pulse width are combined for each of the recording elements and obtained combinations are respectively output to the recording elements. The predetermined number is two or more.

Recording elements are driven by changing a driving pulse applied thereto in accordance with information regarding a total number of times the recording elements have been driven.

An inkjet head drive apparatus comprises a pressure chamber, an actuator, a nozzle and a drive signal output section. The pressure chamber accommodates an ink. The actuator increases or decreases volume of the pressure chamber through an applied a voltage. The nozzle is connected with the pressure chamber to eject the ink through the change in the volume of the pressure chamber. When an ejection pulse for the ejection of the ink from the nozzle is repeated for equal to or greater than three times, the drive signal output section outputs a drive signal having a driving waveform including an initial ejection pulse having a first voltage amplitude and the a second ejection pulses and the pulses thereafter having a second voltage amplitude smaller than the first voltage amplitude to the actuator.

Systems and method of maintaining a uniform temperature distribution in an inkjet head. The inkjet head includes a plurality of ink channels that jet droplets of a liquid material onto a medium using piezoelectric actuators. A temperature controller includes a non-jetting pulse generator that provides non-jetting pulses to one or more of the piezoelectric actuators to generate heat. The non-jetting pulses cause the the piezoelectric actuators to actuate without jetting a droplet from its corresponding ink channel.

There is provided a liquid discharge apparatus, including: a drive element configured to apply discharge energy to the liquid to discharge the liquid; signal generators configured to generate a plurality of types of drive signals having mutually different waveforms to drive the drive element; and drive switches electrically located between the signal generators and the drive element to correspond to the plurality of types of drive signals respectively. The drive switches include a first drive switch and a second drive switch which are different in ON-resistance.

The uniformity of performance of inkjet nozzles within a print head containing a plurality of said nozzles is optimized by characterizing one or more performance attributes of the nozzles within said print head. A waveform set is generated that comprises a plurality of waveforms to compensate for variations of the one or more performance attributes among the nozzles. One of the waveforms within the waveform set is assigned to each nozzle to optimize the one or more performance attributes of each nozzle relative to each other nozzle in the print head. Based upon the waveform assigned to each nozzle, each nozzle in the print head responds substantially uniformly relative to each other nozzle in the print head.

A first output section outputs a first parameter calculated for each nozzle in a group obtained by dividing the nozzles into groups for each certain number so that density unevenness of ink ejected from each nozzle in the group is corrected. A second output section outputs a second parameter calculated for each group so that change rate of the density unevenness between groups is corrected. A first register circuit divides first parameters for each nozzle in the group and stores the first parameters. A second register circuit divides second parameters for each group and stores the second parameters. A multiplication section sequentially multiplies the first parameters by the second parameters. A conversion section converts a multiplication value to correction data of each nozzle. A setting section sets the correction data in a memory.

An example device in accordance with an aspect of the present disclosure includes modules to generate an input signal, apply the input signal to an ink sample to obtain an ink signal, compare the ink signal to a reference value, and identify whether the ink signal is consistent with an ink signature. A module may be contained on an inkjet printhead die.

There is provided a liquid discharge apparatus, including: a drive element configured to apply discharge energy to the liquid to discharge the liquid; signal generators configured to generate a plurality of types of drive signals having mutually different waveforms to drive the drive element; and drive switches electrically located between the signal generators and the drive element to correspond to the plurality of types of drive signals respectively. The drive switches include a first drive switch and a second drive switch which are different in ON-resistance.

Recording elements are driven by changing a driving pulse applied thereto in accordance with information regarding a total number of times the recording elements have been driven.