First electronics may determine a count of bubble jet resistors to be fired by a fire pulse group. A fire pulse generator may generate a fire pulse train for bubble jet resistors, the fire pulse train comprising a precursor pulse and a firing pulse separated by a dead time. Second electronics may adjust a width of the fire pulse for the bubble jet resistors of the fire pulse group by maintaining a first edge of the fire pulse relative to the precursor pulse and adjusting a second edge of the fire pulse relative to the precursor pulse based upon the determined count for the fire pulse group.

Methods and systems are described herein for driving droplet ejection devices with multi-level waveforms. In one embodiment, a method for driving droplet ejection devices includes applying a multi-level waveform to the droplet ejection devices. The multi-level waveform includes a first section having at least one compensating edge and a second section having at least one drive pulse. The compensating edge has a compensating effect on systematic variation in droplet velocity or droplet mass across the droplet ejection devices. In another embodiment, the compensating edge has a compensating effect on cross-talk between the droplet ejection devices.

A method of operating a drop-on demand (DOD) jetting device having a nozzle, a pressure chamber filled with a liquid and connected to the nozzle and an actuator energized by a drive signal, wherein a periodic DOD signal determines whether or not a droplet is jetted out from the nozzle in a given DOD period, and the drive signal has a waveform configured to cause the actuator to excite a pressure wave in the liquid, the method further comprising the steps of a) energizing the actuator with a waveform that has a fixed pattern and extends over a time interval that is longer than the given DOD period; and b) ignoring the DOD signal in at least the first DOD period that follows after said period for which the step a) has been performed.

A liquid ejection method includes ejecting liquid from an ejection opening, using a liquid ejection head including a heating surface configured to heat the liquid and the ejection opening corresponding to the heating surface, by heating the liquid with the heating surface to produce a bubble communicating with air through the ejection opening such that at least a part of the heating surface is exposed to the air through the ejection opening, wherein the liquid is heated with the heating surface for 0.5 microseconds or shorter to produce a bubble communicating with the air through the ejection opening such that at least a part of the heating surface is exposed to the air through the ejection opening, in order to eject the liquid from the ejection opening.

According to an example, in a method for enhancing temperature distribution uniformity across a printer die, in which the printer die includes a plurality of drop generators arranged in a plurality of columns, a warming map that identifies the drop generators of the plurality of drop generators that are to be supplied with warming pulses to enhance temperature distribution uniformity across the printer die may be accessed. The warming map may identify a non-uniform distribution of the drop generators across a column of the plurality of columns. In addition, the warming map may be implemented to supply the drop generators identified in the warming map as the drop generators that are to receive the warming pulses.

A wide array printhead module includes a plurality of printhead die, each of the printhead die includes a number of nozzles. The nozzles form a number of primitives. A nozzle firing heater is coupled to each of the nozzles. An application specific integrated circuit (ASIC) controls a number of activation pluses that activate the nozzle firing heaters for each of the nozzles associated with the primitives. The activation pulses are delayed between each of the primitives via internal delays and external delays to reduce peak power demands of the printhead die. The ASIC determines the internal delays within each printhead die.

According to one embodiment, an inkjet head includes a pressure chamber for ink, a nozzle plate including a nozzle connected to the pressure chamber, an actuator to change a volume of the pressure chamber, and a drive circuit that drives the actuator. The drive circuit drives the actuator according to a drive waveform including an expansion waveform, a first weak contraction waveform, a contraction waveform, and a second weak contraction waveform.

In a case of executing first printing that printing is performed by using a first group, which includes nozzles of a nozzle array whose distances to a detection unit are less than a first predetermined value, and thereafter executing second printing that printing is performed by using a second group, which includes nozzles of the nozzle array whose distances to the detection unit are equal to or less than the first predetermined value and are equal to or more than a second predetermined value, a first driving pulse for the first printing is determined by using a first temperature, which is detected by the detection unit when the first printing is performed. A second driving pulse for the second printing is determined by use of a second temperature, which is derived based on the first temperature and corresponds to a temperature of the nozzles of the second group.

A method for reducing a locally increased viscosity of ink in an ink print head of an ink printer during printing operation includes: a determination of a printing pause with the aid of a pixel preview; an application of a first sequence of pulses for measurement of the activation current of a piezoelement of the ink print head; and an application of a second sequence of pulses for vibration of the ink meniscus at the exit of a nozzle if the ink print head to intermix the ink having locally increased viscosity with ink having the initial viscosity given a threatened failure of the nozzle.

A wide array printhead module includes a plurality of printhead die, each of the printhead die includes a number of nozzles. The nozzles form a number of primitives. A nozzle firing heater is coupled to each of the nozzles. An application specific integrated circuit (ASIC) controls a number of activation pluses that activate the nozzle firing heaters for each of the nozzles associated with the primitives. The activation pulses are delayed between each of the primitives via internal delays and external delays to reduce peak power demands of the printhead die. The ASIC determines the internal delays within each printhead die.