Provided is an inkjet recording apparatus including: a nozzle configured to eject droplets including a first droplet and a second droplet larger than the first droplet; a moving mechanism that moves a sheet relative to the nozzle; and a processor configured to generate ejection data for the droplets, the ejection data corresponding to a dot image formed by ejecting the droplets from the nozzle on the sheet moved relatively to the nozzle by the moving mechanism, wherein the processor is configured to replace the second droplet for a pixel of interest in an original ejection data for generating the ejection data with the first droplet when the droplets are not ejected for a pixels in a row after the pixel of interest to generate the ejection data, where a is an integer of 2 or more.

There are provided a liquid jet head and so on capable of ensuring the ejection stability of the liquid even when jetting the liquid high in viscosity irrespective of the structure of the liquid jet head. The liquid jet head according to an embodiment of the present disclosure includes a plurality of nozzles, an actuator having a plurality of pressure chambers, and a drive section for applying a drive signal to the actuator. The plurality of pulses in the drive signal include at least one first pulse configured to expand the volume of the pressure chamber, and at least one second pulse configured to contract the volume of the pressure chamber, and the pressure in the pressure chamber changes with time including a plurality of extremal values in one cycle. First timing as expansion start timing of the volume of the pressure chamber by the first pulse and second timing as contraction start timing of the volume of the pressure chamber by the second pulse are adjacent to each other, and both of the first timing and the second timing are located in a period between two consecutive extremal values of the plurality of extremal values.

A recording apparatus includes a liquid ejection head, where the liquid ejection head includes: an ejection port, a first substrate, and a temperature detection element. The ejection port ejects liquid and includes a protrusion extending toward an ejection port inside. The first substrate includes a heating element that ejects liquid from the ejection port using heat. The temperature detection element detects temperature of the first substrate. Driving of the heating element is controlled based on whether a difference between a voltage value Vp1 measured by the temperature detection element and a preset voltage value Vp01 has a positive value within or outside a predetermined range or a negative value outside the predetermined range. The voltage value Vp1 is measured when a temperature change amount becomes maximum in a temperature falling process of a second substrate located, after the heating element is driven, at a position corresponding to the heating element.

A liquid discharge apparatus that includes a liquid discharge head including a nozzle discharging liquid onto a recording medium and a pressure generating unit generating pressure by a change in a drive waveform of the liquid, a drive waveform generating unit generating the drive waveform applied to the pressure generating unit, and a waveform selection unit selectively masking a part of the drive waveform and selecting a pulse of the drive waveform, wherein the drive waveform includes at least one discharge pulse and a micro-drive pulse for causing a change in meniscus so that the liquid is not discharged at a point where the liquid is not discharged on the recording medium, wherein the micro-drive pulse is disposed at a head of a discharge cycle of the drive waveform, and wherein the micro-drive pulse is disposed at an integer multiple of a natural vibration cycle Tc of the liquid chamber.

A liquid discharge head includes an actuator and a drive circuit. The actuator is configured to expand and contract a pressure chamber corresponding thereto. The drive circuit is configured to, during a dot formation cycle apply a first discharge pulse to the actuator to cause a first droplet to be discharged from the pressure chamber, and after a predetermined rest period, during which no discharge pulse is applied to the actuator, has elapsed from application of the first discharge pulse, apply a second discharge pulse to the actuator to cause a second droplet to be discharged from the pressure chamber.

A liquid discharge apparatus includes a liquid discharge head to discharge liquid and control circuitry to generate a drive waveform including drive pulses applied to the head. The drive waveform includes a non-discharge pulse not to discharge the liquid and a discharge pulse to discharge the liquid. The non-discharge pulse and the discharge pulse are serial in time in the drive waveform. Td is in a range of Tc0.2Tc to Tc+0.45Tc. Vp1 is in a range of 10% to +10% of Vpp1. Td represents a time interval between the non-discharge pulse and the discharge pulse. Tc represents a natural vibration period of a pressure chamber of the head. Vp1 represents a peak value of the non-discharge pulse. Vpp1 represents a peak value of the non-discharge pulse at which a droplet speed of liquid discharged by the discharge pulse takes a local minimum value.

In an example implementation, a method of reducing inkjet aerosol in a fluid drop ejection system includes imaging fluid drops from an ejection event as the drops travel from an ejection nozzle toward a substrate, determining the momentum of each fluid drop from the imaging, comparing the momentum of each fluid drop with a threshold momentum, and determining that a fluid drop will become aerosol when its momentum does not exceed the threshold momentum.

A liquid discharge head includes an actuator and a drive circuit. The actuator is configured to expand and contract a pressure chambers. The drive circuit is configured to apply a first drive waveform to cause the actuator to discharge a liquid droplet at a first speed, and then a second drive waveform after the first drive waveform to cause the actuator to discharge a liquid droplet at a second speed slower than the first speed.

A liquid discharge apparatus that includes a liquid discharge head including a nozzle discharging liquid onto a recording medium and a pressure generating unit generating pressure by a change in a drive waveform of the liquid, a drive waveform generating unit generating the drive waveform applied to the pressure generating unit, and a waveform selection unit selectively masking a part of the drive waveform and selecting a pulse of the drive waveform, wherein the drive waveform includes at least one discharge pulse and a micro-drive pulse for causing a change in meniscus so that the liquid is not discharged at a point where the liquid is not discharged on the recording medium, wherein the micro-drive pulse is disposed at a head of a discharge cycle of the drive waveform, and wherein the micro-drive pulse is disposed at an integer multiple of a natural vibration cycle Tc of the liquid chamber.

A head voltage correcting method for inkjet printing apparatus which perform printing with a head having a plurality of head modules includes the following steps: a testing chart printing step for printing testing charts which includes a lowest density head module check pattern, satellite check patterns, band-by-band density variable patterns, and in-band density variable patterns; a lowest density head module determining step for determining a lowest density head module; a satellite-free drive voltage determining step; and a new reference voltage determining step for determining a drive voltage of the band-by-band density variable patterns of the adjacent head module to be a new reference voltage for the adjacent head module.