Abstract: An inkjet recording apparatus including: a recording head having a pressure chamber, and a pressure generation device to change a volume of the pressure chamber, wherein the recording head ejects an ink in the pressure chamber as an ink droplet from a nozzle by driving the pressure generation device based on drive signals; and a drive signal generating section to generate the drive signals, which include: an ejection pulse including a first pulse for expanding the volume of the pressure chamber and then contracting the volume; a preliminary pulse, to be applied immediately before the first pulse, for contracting the volume of the pressure chamber and then expanding the volume, and wherein the preliminary pulse is a rectangular wave having a pulse width of 2AL or greater, where AL is ½ of an acoustic resonance cycle period of a pressure wave in the pressure chamber.

Abstract: An inkjet recording apparatus including: a recording head having a pressure chamber, and a pressure generation device to change a volume of the pressure chamber, wherein the recording head ejects an ink in the pressure chamber as an ink droplet from a nozzle by driving the pressure generation device based on drive signals; and a drive signal generating section to generate the drive signals, which include: an ejection pulse including a first pulse for expanding the volume of the pressure chamber and then contracting the volume; a preliminary pulse, to be applied immediately before the first pulse, for contracting the volume of the pressure chamber and then expanding the volume, and wherein the preliminary pulse is a rectangular wave having a pulse width of 2 AL or greater, where AL is ½ of an acoustic resonance cycle period of a pressure wave in the pressure chamber.

Abstract: A liquid droplet ejecting apparatus having: a pressurizing device; a pressure generation chamber whose volume expands or contracts by a movement of the pressurizing device; a liquid droplet ejecting head having a nozzle communicating with the pressure generation chamber; and a drive signal generator which generates the drive signal for operating the pressurizing device, and causing to eject liquid droplets through the nozzle, wherein the drive signal comprises: an expansion pulse to expand the volume of the pressure generation chamber; a first contraction pulse following the expansion pulse to contract the volume; and a second contraction pulse after the first contraction pulse to contract the volume, wherein a pulse width of the expansion pulse is 0.7AL through 1.3AL, and a pulse width of the first contraction pulse is 0.3 AL through 1.5 AL, where AL is ½ of an acoustic resonance period of the pressure generation chamber.

Abstract: The present liquid ejecting device adjusts the cross-talk amount to a range of ± 15 %, by providing: a recording head having actuators which generate the ejection energy for ejecting the liquid from a plurality of nozzles for each of the plurality of nozzles; a drive circuit to generate the drive signal for driving the actuator; and an adjusting circuit for adjusting at least one of the rising time constant and the falling time constant of the waveform of the drive signal to a time period more than 30 nsec and less than 150 nsec before the drive signal reaches the actuator.

Abstract: A liquid jetting device having: a recording head including a jetting energy generating element; a drive circuit generating drive signal for the element; a liquid detection sensor detecting a jetting characteristic value of liquid jetted from a nozzle; a drive voltage adjustment unit adjusting a voltage value of the drive signal; and a controller to control the drive circuit, the sensor and the drive voltage adjustment unit, wherein the controller performs control so that the liquid is jetted, and creates a correction data from the jetting characteristic value; and the controller performs control so that the voltage value is corrected based on a value obtained by multiplying the correction data by convergence coefficient within a range from 0.50 or more to less than 1.00, and repeats correcting the voltage value until a detection result of the liquid jetted based on the drive signal after the correction becomes a target value.

Abstract: An inkjet recording apparatus having a head that ejects ink droplets, a temperature detector that detects temperatures in the vicinity of the head, and a drive waveform controller that generates a drive waveform driving the head, wherein the drive waveform controller changes, based on temperature information coming from the temperature detector, the amplitude as temperature changes, according to the expression V=EXP(A/T+B) wherein V represents an amplitude of the drive waveform, T represents the temperature and A and B represent a constant.

Abstract: A droplet ejection apparatus provided with: a drive signal generator for generating drive signals including a plurality of drive pulses; a drive pulse selector for selecting drive pulses in accordance with a print datum of each pixel; and a head for ejecting a droplet from a nozzle provided corresponding to a channel, by changing a volume of the channel according to the drive pulses selected, wherein, the drive signal includes a micro-vibration pulse as one of the drive pulses to generate a micro-vibration of meniscus in the nozzle in such a degree that the droplet is not ejected, said micro-vibration pulse being formed of rectangular waves which include at least one micro-vibration pulse having a pulse width of (2n) AL, where AL is ½ of the acoustic resonance period of the channel, and n is an integer not smaller than 1.

Abstract: A liquid droplet ejecting apparatus having: a pressurizing device; a pressure generation chamber whose volume expands or contracts by a movement of the pressurizing device; a liquid droplet ejecting head having a nozzle communicating with the pressure generation chamber; and a drive signal generator which generates the drive signal for operating the pressurizing device, and causing to eject liquid droplets through the nozzle, wherein the drive signal comprises: an expansion pulse to expand the volume of the pressure generation chamber; a first contraction pulse following the expansion pulse to contract the volume; and a second contraction pulse after the first contraction pulse to contract the volume, wherein a pulse width of the expansion pulse is 0.7AL through 1.3AL, and a pulse width of the first contraction pulse is 0.3 AL through 1.5 AL, where AL is ½ of an acoustic resonance period of the pressure generation chamber.

Abstract: A liquid jetting device having: a recording head including a jetting energy generating element; a drive circuit generating drive signal for the element; a liquid detection sensor detecting a jetting characteristic value of liquid jetted from a nozzle; a drive voltage adjustment unit adjusting a voltage value of the drive signal; and a controller to control the drive circuit, the sensor and the drive voltage adjustment unit, wherein the controller performs control so that the liquid is jetted, and creates a correction data from the jetting characteristic value; and the controller performs control so that the voltage value is corrected based on a value obtained by multiplying the correction data by convergence coefficient within a range from 0.50 or more to less than 1.00, and repeats correcting the voltage value until a detection result of the liquid jetted based on the drive signal after the correction becomes a target value.

Abstract: The present liquid ejecting device adjusts the cross-talk amount to a range of ±15%, by providing: a recording head having actuators which generate the ejection energy for ejecting the liquid from a plurality of nozzles for each of the plurality of nozzles; a drive circuit to generate the drive signal for driving the actuator; and an adjusting circuit for adjusting at least one of the rising time constant and the falling time constant of the waveform of the drive signal to a time period more than 30 nsec and less than 150 nsec before the drive signal reaches the actuator.

Abstract: An inkjet recording apparatus having a head that ejects ink droplets, a temperature detector that detects temperatures in the vicinity of the head, and a drive waveform controller that generates a drive waveform driving the head, wherein the drive waveform controller changes, based on temperature information coming from the temperature detector, the amplitude as temperature changes, according to the expression V=EXP(A/T+B) wherein V represents an amplitude of the drive waveform, T represents the temperature and A and B represent a constant.

Abstract: An ink-jet recording apparatus in which an electromechanical converting device that changes a volume of an ink channel of a recording head is driven to make an ink droplet to jet from a nozzle, wherein before an ink droplet jetting operation is conducted, an ink meniscus of the ink channel is vibrated finely by repeating plural times a pushing out process so that a distance corresponding to a peak of the ink meniscus pushed out from a surface of the nozzle is equal to or more than a radius of the nozzle and a process for pulling in more toward the ink channel across a repose position, while the ink is prevented from jetting from the nozzle.

Abstract: A droplet ejection apparatus provided with: a drive signal generator for generating drive signals including a plurality of drive pulses; a drive pulse selector for selecting drive pulses in accordance with a print datum of each pixel; and a head for ejecting a droplet from a nozzle provided corresponding to a channel, by changing a volume of the channel according to the drive pulses selected, wherein, the drive signal includes a micro-vibration pulse as one of the drive pulses to generate a micro-vibration of meniscus in the nozzle in such a degree that the droplet is not ejected, said micro-vibration pulse being formed of rectangular waves which include at least one micro-vibration pulse having a pulse width of (2n) AL, where AL is ½ of the acoustic resonance period of the channel, and n is an integer not smaller than 1.

Abstract: An ink-jet recording apparatus in which an electromechanical converting device that changes a volume of an ink channel of a recording head is driven to make an ink droplet to jet from a nozzle, wherein before an ink droplet jetting operation is conducted, an ink meniscus of the ink channel is vibrated finely by repeating plural times a pushing out process so that a distance corresponding to a peak of the ink meniscus pushed out from a surface of the nozzle is equal to or more than a radius of the nozzle and a process for pulling in more toward the ink channel across a repose position, while the ink is prevented from jetting from the nozzle.

Abstract: A process and an apparatus for converting multi-valued image data obtained, for a plurality of pixels of a continuous tone image, by an image input device, into binary image data representing a halftone image to be output by an image output device. The conversion is performed by comparing the multi-valued image data for the plurality of pixels with threshold values, which are determined in advance so as to be specific to a combination of the image input device and the image output device. Alternatively, the multi-valued image data may be corrected before comparison with threshold values, by using correction data which is determined in advance so as to be specific to a combination of the image input device and the image output device.