According to one or more embodiments, the inkjet head includes an actuator and a driver. The actuator causes a pressure chamber to expand or contract. The driver applies an ejection pulse to the actuator to eject ink from the pressure chamber. The ejection pulse includes an expansion pulse having a width of 0.75 to 1.25 times a pressure propagation time of the pressure chamber, a rest period after the expansion pulse, and a contraction pulse after the rest period.

A method for depositing droplets onto a medium, utilising a droplet deposition head is provided. The head used in the method includes: an array of fluid chambers separated by interspersed walls, each fluid chamber communicating with an aperture for the release of fluid droplets and each wall separating two neighbouring chambers. Each wall is actuable such that in response to a first voltage, it will deform so as to decrease the volume of one chamber and increase the volume of the other chamber, and, in response to a second voltage, it will deform so as to cause the opposite effect on the volumes of its neighbouring chambers. The method includes the steps of: receiving input data: assigning, based on such input data, all the chambers within the array as either filing chambers or non-firing chambers, so as to produce bands of one or more contiguous filing chambers separated by bands of one or more contiguous non-firing chambers; actuating the walls of certain of the chambers such that: for each non-firing chamber, either one wall is stationary while the other is moved, or the walls move with the same sense, or they remain stationary: and, for each firing chamber the walls move with opposing senses; such actuations result in each firing chamber releasing at least one droplet, the resulting droplets forming bodies of fluid disposed on a line on the medium, such bodies of fluid being separated on the line by respective gaps for each of the bands of non-firing chambers, the size of each such gap generally corresponding in size to the respective band of non-firing chambers. The actuations of the walls of said firing chambers in the actuating step are such that, if only one of the two walls of each firing chamber were actuated in such manner, no droplets would be ejected from that firing chamber. A droplet deposition apparatus, a droplet deposition head and a computer program product are also provided.

A jet parameter generation system according to an embodiment of the present disclosure includes a data acquisition section, and a parameter generation section for generating a predetermined jet parameter, using a predetermined analytical method of taking a predetermined input parameter as an explanatory variable and taking a predetermined jet parameter as an objective variable. The parameter generation section determines which one of a first standard for setting a voltage value with which a drop volume of the liquid to be a reference is obtained and a second standard for setting a voltage value with which an ejection speed of the liquid to be a reference is obtained is to be selected, selects a first explanatory variable group when determining to select the first standard, while selecting a second explanatory variable group when determined to select the second standard, and uses the predetermined analytical method using just selected one of the first explanatory variable group and the second explanatory variable group to thereby generate the predetermined jet parameter.

A liquid ejection apparatus includes a liquid ejection unit with a plurality of nozzles and a corresponding plurality of actuators. A drive waveform generation circuit is configured to generate drive waveforms having different drive timings. An actuator drive circuit is configured to apply a first drive waveform to a first actuator in a liquid ejection operation and a second drive waveform to a second actuator in the liquid ejection operation during which the first and second actuators are to be driven at a same nominal time. The first driving waveform is different from the second drive waveform, and the first actuator is at a position electrically closer along a predetermined direction to a power supply electrode than is the second actuator.

In accordance with an embodiment, an inkjet head comprises a pressure chamber, an actuator and a control section. The pressure chamber houses ink. The actuator is driven to expand or contract the volume of the pressure chamber in order to eject the ink from an opening of the pressure chamber. The control section applies an expansion pulse of which the width is 0.4 times-0.9 times as large as an AT which is half a natural vibration period during which nozzle negative pressure is changed in the pressure chamber and which expands the pressure chamber to the actuator, and applies a contraction pulse which contracts the pressure chamber to the actuator.

A correction data setting apparatus, which sets correction data in a memory for storing the correction data for correcting a pulse width of a drive pulse signal applied to each actuator corresponding to each nozzle of an inkjet head, comprises a generation section which sequentially generates a channel No. for individually identifying each nozzle; an output section which outputs a parameter required for arithmetic which represents a characteristic of a correction amount with respect to an arrangement direction of the nozzles; an arithmetic section which executes the arithmetic using the parameter output from the output section to calculate the correction amount for each channel No. generated from the generation section; a conversion section converts the correction amount calculated for each channel No. by the arithmetic section to the correction data; and a setting section sets the correction data obtained for each channel No. by the conversion section in the memory.

In accordance with an embodiment, an inkjet head comprises a first actuator and a second actuator, a first electrode, a second electrode, a third electrode, and a drive controller. The first actuator and the second actuator constitute a pressure chamber. The first electrode comes in contact with the first actuator from the outer side of the pressure chamber. The second electrode comes in contact with the first actuator and the second actuator from the inner side of the pressure chamber. The third electrode comes in contact with the second actuator from the outer side of the pressure chamber. The drive control section outputs an auxiliary pulse which generates volume change in the pressure chamber that is smaller than volume change of the pressure chamber generated by an ejection pulse for ejecting ink from the pressure chamber to the first electrode, the second electrode, and the third electrode.

A liquid ejection head includes: a piezoelectric actuator configured to be deformed depending on a driving pulse applied thereto so as to eject liquid filled in a pressure chamber from a nozzle, a ratio of a first local maximum value which is a largest value among a plurality of local maximum values of an ejection speed of the liquid depending on a pulse width and a second local maximum value which is a second largest value thereamong satisfying a predetermined condition; and a control unit configured to successively apply a first driving pulse and a second driving pulse to the piezoelectric actuator.

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.

An inkjet head includes an actuator that deforms in response to a drive signal from a drive circuit to change a volume of a pressure chamber to eject ink from a nozzle connected to the pressure chamber. The drive signal includes a main interval during which the ink is ejected and an auxiliary interval during which the ink is not ejected. The main interval includes a first pulse applying a first voltage, a first period maintaining the reference potential, and a second pulse applying a second voltage having a polarity opposite from the first voltage. The auxiliary interval is prior to the main interval and includes a third pulse applying a third voltage having the same polarity as the first voltage and a second period maintaining the reference potential.