Abstract: The printing method includes the following steps of: preparing a printing apparatus that includes an element that is driven in order to form a dot, a first drive signal generation section that generates drive signals for driving the element, and a second drive signal generation section that generates drive signals for driving the element; at a certain timing, forming a dot of a predetermined size by generating a first drive signal with the first drive signal generation section and by generating a second drive signal that is different from the first drive signal with the second drive signal generation section; and at a separate timing, forming a dot of the predetermined size by generating the first drive signal with the second drive signal generation section. With this printing method, the first drive signal generation section and the second drive signal generation section can be made to generate an equal amount of heat.

Abstract: The inkjet recording apparatus has a color ink recording head to jet color ink toward a recording medium; an invisible ink recording head to jet invisible ink toward the recording medium; and a light irradiating device to irradiate light toward the recording medium to cure the ink. A control section causes the color ink to be jetted then the light irradiating device irradiates the color ink, thereafter the invisible ink is jetted, and finally the light irradiating device irradiates the invisible ink after a lapse of a certain time from the invisible ink jetting.

Abstract: A drop emitting device that includes a drop generator, a drive signal including a plurality of fire intervals applied to the drop generator, wherein the drive signal includes in each fire interval a bi-polar drop firing waveform or a time varying non-firing waveform.

Abstract: A printhead assembly that has a printhead substrate having a plurality of drop generators formed thereon at an area density of at least six drop generators per square millimeter. The droplets emitted have a drop volume less than 8 pico liters. The fluid forming the droplets has a viscosity in the range of 2 to 5 centipoise. A high area density of drop generators and relatively low droplet volume of water-based ink provides high print resolutions and energy efficient operation.

Abstract: A liquid ejecting apparatus including a pressure generating unit capable of changing a pressure of liquid contained in the pressure chamber, a liquid ejecting head capable of discharging liquid droplets from a nozzle opening by actuating the pressure generating unit, a passage extending from a common liquid chamber through a pressure chamber to the nozzle opening and a driving signal generating unit that repeatedly generates a plurality of driving signals causing the liquid droplets to be discharged by actuating the pressure generating unit. In order to prevent the vibration resulting from a first driving pulse sent to a first pressure generating unit from interfering with the discharge in an adjacent pressure chamber, a second driving signal including a second discharge pulse, is generated at a period of time after to the first discharge pulse corresponding to a characteristic vibration period of the liquid contained in the pressure chamber.

Abstract: A nozzle assembly for an inkjet printhead is disclosed. The nozzle assembly includes an inkjet nozzle having an actuator for ejecting an ink droplet from the inkjet nozzle when a resistive element of the actuator is heated by an electrical current. A drive transistor provides an energy pulse to the resistive element of the actuator, and control logic controls the drive transistor. The energy of the energy pulse is less than 1 ?J.

Abstract: A nozzle assembly for an inkjet printhead is disclosed. The nozzle assembly includes an inkjet nozzle having an actuator for ejecting an ink droplet from the inkjet nozzle when a resistive element of the actuator is heated by an electrical current, a shift register comprising a plurality of successive registers, the shift register receives input data in a first register, and shifts the input data to successive registers upon receipt of a shift signal, a transfer register for latching data in one of the registers of the shift register; a control gate for outputting a control pulse in response to data in the transfer register, and a drive transistor for providing an energy pulse to the resistive element of the actuator upon receipt of the control pulse. Each energy pulse has energy of less than 1 microjoule.

Abstract: A drive power control device according to the present invention includes a transistor, which is input with a driving signal before current amplification into a base thereof, and which amplifies a current of the driving signal to drive an actuator; a switching element, which switches an input of a supply voltage to a collector of the transistor between on and off; and a voltage comparator, which compares a base voltage and a collector voltage of the transistor, and which controls the switching element such that the input of the supply voltage to the collector is turned off when a predetermined voltage difference occurs, and the input of the supply voltage to the collector is turned on when a predetermined voltage difference does not occur.

Abstract: In an ink jet head driving method for applying a drive pulse to an actuator ACT to change capacities of a plurality of pressure chambers in which ink has been filled, ejecting an ink droplet from a nozzle formed in communication with the pressure chamber to print onto a printing medium, and moreover, controlling the number of ink droplets ejected according to the number of drive pulses to carry out gradation printing, a control is made such that, in the case where the number of ink droplets is small, a boost pulse Pb for amplifying a pressure vibration of the pressure chamber is applied prior to a drive pulse for ejecting a first ink droplet, and in the case where the number of ink droplets is large, applying of the boost pulse Pb is disabled.

Abstract: A controller controls a pressurizing actuator in such a manner that a pressure chamber changes from a first state where a volume of the pressure chamber is V1 to a second state where the volume is V2 larger than V1 and then returns from the second to the first state to cause ink to be ejected from an ejection opening, that a time length Tv1 from a time point at which the pressure chamber starts to change from the first to the second state to a time point at which the pressure chamber is in the second state becomes 33% or more of a characteristic vibration period Td of ink filled in a first ink passage extending from an outlet of the pressure chamber to the ejection opening, and that the time length Tv1 becomes 83% or less of the characteristic vibration period Td.

Abstract: An inkjet deposition apparatus includes a position encoder 128 in a translation stage 116. The position encoder provides encoder signals which are used as a clock signal for a pattern memory 136. Ejection of droplets of a material to be printed can therefore be synchronised with the speed of movement of the translation, providing improved accuracy and speed of deposition.

Abstract: An actuator can selectively switch a volume of a pressure chamber between a first state V1 and a second state V2, which is greater than V1. The actuator changes from the first state into the second state and then changes back into the first state to eject ink from an ejection port. A controller controls the actuator such that To/Tc falls within a range from 0.51 to 0.54. To represents the time period between time the actuator starts to change from the first state into the second state, to a time the actuator starts to change from the second state into the first state. Tc represents the period of proper oscillation of ink filling up the individual ink passage. The actuator is controlled so that a variation in ink ejection speed is prevented from being too large relative to the variation in the degree of deformation of the actuator.

Abstract: An inkjet printer comprises a printhead having a plurality of inkjet nozzles, a controller connected to the printhead for controlling a timing of firing pulses, and feedback lines for communicating sensed printhead feedback to the controller. The controller is configured to adjust the timing of the firing pulses in response to the feedback communicated to the controller from the printhead.

Abstract: An inkjet printhead with an array of nozzles 26 and corresponding heaters 10 configured for heating printing fluid 20 to nucleate a vapor bubble 12 that ejects a drop 24 of the printing fluid through the nozzle. Drive circuitry 22 generates an electrical drive pulse to energize the heaters 10 and is configured to adjust the drive pulse power to vary the vapor bubble nucleation time. By varying the power of the pulse used to generate the bubble, the printhead can operate with small, efficiently generated bubbles during normal printing, or it can briefly operate with large high energy bubbles if it needs to recover decapped nozzles.

Abstract: The invention provides methods, systems, and drivers for controlling an inkjet printing system. The driver may include logic including a processor, memory coupled to the logic, and a fire pulse generator circuit coupled to the logic. The fire pulse generator may include a connector to facilitate coupling the driver to a print head. The fire pulse generator circuit may also include a fixed current source circuit adapted to generate a fire pulse with a constant slew rate that facilitates easy adjustment of ink drop size. The logic is adapted to receive an image and to convert the image to an image data file. The image data file is adapted to be used by the driver to trigger the print head to deposit ink into pixel wells on a substrate as the substrate is moved in a print direction. Numerous other aspects are disclosed.

Abstract: An image forming apparatus with reduced momentary current consumption is provided. The apparatus includes: a plurality of drive waveform generating circuits; a circuit selection device which selectively switches the drive waveform generating circuits for applying the drive signal waveforms to pressure generating elements; a power source which supplies power to the pressure generating elements via the drive waveform generating circuits; and a control device which selects a first drive waveform generating circuit used for driving each of the pressure generating elements, with respect to each of the pressure generating elements, of the plurality of drive waveform generating circuits, in such a manner that no drive waveform generating circuit in which an amount of momentary current consumption exceeds a prescribed tolerable value, of the plurality of drive waveform generating circuits, exists.

Abstract: A liquid-jet head selectively forms a large dot or a small dot. The large dot is ejected when a plurality of pulse signals are selected, and the small dot upon selection of a smaller number of the pulse signals. There is a contraction of the pressure generating chamber to eject a droplet through the nozzle, and a vibration damping step. The drive waveforms are set to implement this approach, and have particular characteristics.

Abstract: A photo printer that prints 6?×4? photos that has a stationary 4? printhead. The printhead has a plurality of color channels, each color channel comprising at least one nozzle row extending along the length of said printhead, each nozzle in a color channel ejecting the same colored ink. The photo printer also has means for continuously moving 6?×4? paper sheets past the printhead and a controller for selecting firing nozzles from each color channel of the printhead. During use, all firing nozzles of each color channel selected for one line of printing are fired within about 200 microseconds.

Abstract: An image forming apparatus is disclosed that includes a recording head including a nozzle from which liquid droplets are ejected, a pressure chamber communicating with the nozzle and containing liquid, and a pressure generation part changing the volume of the pressure chamber; and a drive signal generation part generating a drive signal including multiple drive pulses and causing the pressure generation part to operate so that the liquid droplets are ejected. The drive signal generated by the drive signal generation part includes, within a single print cycle, a resonant drive pulse causing a first one of the liquid droplets to be ejected using the natural vibration period of the pressure chamber, a non-resonant drive pulse causing a second one of the liquid droplets to be ejected without using the natural vibration period of the pressure chamber, and a slight drive pulse prevented from causing the ink droplets to be ejected.

Abstract: In order to preserve good droplet discharge efficiency in a droplet discharge device, a plurality of timings are set within a period in which a plurality of droplets are to be discharged to a target position. Consecutive timings are divided by a cycle time of pressure wave that is generated inside a pressure chamber by transmitting a signal to an actuator. When a plurality of signals are applied to the actuator at consecutive timings, the peak of the pressure wave and the application of the signals are synchronous, and the droplet discharge efficiency will be improved. However, the consecutive number of timings at which the consecutive signals are transmitted is limited to a predetermined number. In this way, the pressure inside the pressure chamber can be prevented from becoming too high.

Abstract: In one embodiment, a method for driving a droplet ejection device having an actuator includes applying a low power multi-pulse waveform having at least two drive pulses and at least one intermediate portion to the actuator. The method further includes alternately expanding and contracting a pumping chamber coupled to the actuator in response to the at least two drive pulses and the at least one intermediate portion. The method further includes causing the droplet ejection device to eject one or more droplets of a fluid in response to the pulses of the low power multi-pulse waveform. In some embodiments, at least one intermediate portion has a voltage level greater than zero and less than or equal to a threshold voltage level in order to reduce the power needed to operate the droplet ejection device.

Abstract: Described herein is a method and apparatus for driving a droplet ejection device with multi-pulse waveforms. In one embodiment, a method for driving a droplet ejection device having an actuator includes applying a multi-pulse waveform having two or more drive pulses and a cancellation pulse to the actuator. The method further includes generating a pressure response wave in a pumping chamber in response to each pulse. The method further includes causing the droplet ejection device to eject a droplet of a fluid in response to the drive pulses of the multi-pulse waveform. The method further includes canceling the pressure response waves associated with the drive pulses with the pressure response wave associated with the cancellation pulse.

Abstract: Described herein is a process and apparatus for driving a droplet ejection device with embedded multi-pulse waveforms. In one embodiment, the process includes generating a multi-pulse waveform that includes drive pulses in predetermined positions. Next, the process includes applying the drive pulses to the actuator and causing the droplet ejection device to eject a first droplet of a fluid. The process also includes applying a second multi-pulse waveform having at least one embedded pulse to the actuator and causing the droplet ejection device to eject a second droplet of the fluid. Each embedded pulse is embedded between predetermined positions of two drive pulses. In some embodiments, the first and second droplets have different droplet sizes and these droplets are ejected at substantially the same effective drop velocity.

Abstract: The liquid ejection head comprises: a nozzle through which liquid is ejected; a pressure chamber which stores the liquid ejected through the nozzle; a pressurizing device which changes a volume of the pressure chamber to apply pressure to the liquid stored in the pressure chamber; and a supply port through which the liquid is supplied to the pressure chamber, wherein the liquid ejection head has a structure such that inertance Mn of the nozzle, liquid resistance Rn of the nozzle, compliance Cn caused by a surface tension of the liquid in the nozzle, inertance Ms of the supply port, and liquid resistance Rn of the supply port satisfy the following inequality: 4 · ( Mn + Ms ) Cn ? ( Rn + Rs ) 2 , so that oscillation of a meniscus surface located in vicinity of the nozzle is controlled at a time of refill when the liquid is filled in the pressure chamber through the supply port after the liquid is ejected from the nozzle.

Abstract: An inkjet recording apparatus including: a recording head movable in a main scanning direction, and including: an ink passage; a nozzle communicated with the passage; and an actuator applying energy to ink in the passage to eject a droplet thereof from the nozzle; a control device outputting a drive waveform signal, while the head is moved in the direction, to drive the actuator, the control device including: a storing portion storing plural kinds of the signals different from one another in the number of the ejected droplets for one dot; and an outputting portion including: a determining portion making at least one of the following determinations, for each particular one of dots printed in series at least in the direction: whether there is a dot printed immediately before the particular dot, and whether there is a dot printed immediately after the particular dot; and a selecting portion selecting one of the kinds of the signals, based on a result of the determination made by the determining portion, and outp

Abstract: A testing method includes sorting inkjet heads into a plurality of groups on the basis of known information about ink flow, preparing basic driving waveform data corresponding to each of the groups and modification data that partially modifies the basic driving waveform data to individually store them in advance in a storing section, creating individual waveform information that instructs combinations of the basic driving waveform data with the modification data with respect to an inkjet head to be tested to apply a modified driving waveform, and repeating the modification of the individual waveform information until a recording state becomes good.

Abstract: A liquid ejecting apparatus includes: a head having a nozzle; a pressure-changing unit for changing pressure of liquid in the nozzle in such a manner that the liquid is ejected from the nozzle; a level-data setting unit for setting a selected level data from a plurality of level data, based on an ejecting data; a driving-signal generator for generating a first driving signal and a second driving signal; and a driving-pulse generator for generating a driving pulse based on the selected level data and the first driving signal and the second driving signal. The first driving signal and the second driving signal are periodical signals having a same period. The first driving signal includes a first large-drop pulse-wave and a third large-drop pulse-wave. The second driving signal includes a second large-drop pulse-wave. The first large-drop pulse-wave, the second large-drop pulse-wave and the third large-drop pulse-wave have a same waveform, and appear in that order at regular intervals.

Abstract: An image forming method for use in an inkjet head includes a pressure chamber filled with ink, a nozzle which communicates with the pressure chamber and in which a meniscus of the ink is formed, a piezoelectric element which pressurizes the pressure chamber, and a drive circuit which performs an operation of ejecting the ink in a printing state and generates a basic pulse for vibrating the meniscus in a non-printing state. The basic pulse is generated by turning off a voltage applied to the piezoelectric element for substantially the same period as a natural vibration period of the ink. An additional pulse is generated at least once before or after the basic pulse when the basic pulse is generated by the drive circuit in the non-printing state. The additional pulse is generated by turning off the voltage applied to the piezoelectric element.

Abstract: A liquid droplet ejecting head includes: an ejector having a nozzle, a pressure chamber, and a drive element that applies pressure to a liquid inside the pressure chamber; and a controller that applies a drive waveform to the drive element. The controller vibrates a flow velocity of the liquid ejected from the nozzle in a first positive direction vibration mode for causing a leading end portion of the liquid droplet to be ejected from the nozzle toward the opposite side of the pressure chamber side; and a second positive direction vibration mode for adjusting the velocity of a trailing end portion of the liquid droplet. An interval between the first positive direction vibration mode and the second positive direction vibration mode is set so as to make the velocity of the trailing end portion of the columnar liquid droplet faster than the velocity of the leading end portion thereof.

Abstract: There is disclosed an ink-droplet ejecting apparatus including: ink passages each including a pressure chamber filled with ink; actuators each operated to change, upon receiving a drive signal, an inner volume of one of the chambers to generate a pressure wave in the ink in the chamber which propagates along the passage to eject a droplet of the ink onto a recording medium; and a control unit connected to the actuators and supplying the signal to the actuators such that the signal is in one of at least one waveform including a waveform which is for forming a single dot on the medium and includes a main pulse for ejecting the droplet, a preceding pulse outputted before the main pulse, and a stabilizing pulse outputted after the main pulse. A pulse width of the main pulse is not coincident with a one-way propagation time AL which is a time taken by the pressure wave to propagate one way along the passage. The preceding pulse is outputted in a manner not to eject the droplet.

Abstract: A droplet ejection apparatus comprises: (a) a recording head including a nozzle from which a droplet of a liquid is ejected, (b) a pressure chamber which is filled with the liquid and whose volume is changeable for ejecting the droplet from the nozzle, and (c) an actuator which changes the volume of the pressure chamber by a drive pulse inputted thereto; and an operating device which outputs the drive pulse to the actuator and which is capable of performing a restoring operation for restoring a droplet ejection performance of the recording head. The restoring operation includes: a first operation for outputting, a plurality of times, an ejection drive pulse as the drive pulse by which the droplet can be ejected; and a second operation for outputting, a plurality of times, a non-ejection drive pulse as the drive pulse by which the droplet can not be ejected, the second operation being performed following the first operation.

Abstract: The present invention relates to a method of printing using dots of ink discharged from nozzles to form the image. To ensure quality and efficiency of printing, a feed back mechanism from the printhead is used, to provide real time readings on various parameters of the printhead. These readings are compared to a pulse parameter table, to adjust the parameter of the pulse to ensure quality and efficiency of the printing. The temperature of the printhead is sensed to allow the timing of the firing pulses to be adjusted to take into consideration the viscosity of the ink. The amount of voltage available to the pulse actuator can be sensed so that the pulse width can be adjusted to compensate for a flat battery or high voltage source. The resistivity of the actuator heater can be sensed so as to adjust the pulse widths to maintain a constant energy irrespective of the heater resistivity.

Abstract: An ink jet printer has an ink jet head comprising a nozzle that discharges an ink droplet toward a print medium, and an actuator that makes the nozzle discharge the ink droplet when a pulse signal is applied to the actuator. An applying device can apply at least two kinds of pulse signals to the actuator. The pulse width of each kind of pulse signal mutually differs. A first storage stores at least two kinds of base pulse widths. Each kind of base pulse width mutually differs and corresponds with a different kind of pulse signal. An inputting device inputs a predetermined value which is stored in the second storage. The applying device determines a pulse width of each kind of pulse signal by multiplying the corresponding base pulse width stored in the first storage by the predetermined value stored in the second storage.

Abstract: A liquid ejecting apparatus includes liquid chambers in which a liquid is filled, nozzles communicating with the liquid chambers, a signal generator generating a signal of potential change, and elements operating in accordance with the potential of the signal to be applied to cause a change in pressure in the liquid chambers. The signal generator generates a signal for micro vibration of a free surface of the liquid to be exposed from the nozzles such that the liquid is not ejected. The signal for micro vibration has a first potential change portion at which a potential changes from a first potential to a medium potential between the first potential and a second potential, a subsequent constant potential portion at which the potential is maintained constant at the medium potential, and a subsequent second potential change portion at which the potential changes from the medium potential to the second potential.

Abstract: Charge leakage prevention and voltage drift prevention on a droplet ejection device for an inkjet printer. In one method to prevent charge leakage on a droplet ejection device with a switch and a piezoelectric actuator, the method includes controlling the switch to drive the piezoelectric actuator with the waveform input signal during a droplet firing period, and controlling the switch to drive the piezoelectric actuator with a constant voltage level during a non-firing period.

Abstract: A liquid jet apparatus includes a plurality of nozzles provided to a liquid jet head, an actuator provided corresponding to each of the nozzles, and drive unit for applying a drive pulse to the actuator, wherein the drive unit includes drive waveform signal generation unit that generates one or more of drive waveform signals each providing basis of the drive pulse to the actuator, one or more of transistor pairs provided as many as the number of the actuators in order for power-amplifying the one or more of drive waveform signals generated by the drive waveform signal generation unit, and each having two transistors forming a pair and connected to each other in a push-pull manner, and one or more of low-pass filters provided as many as the number of the actuators and each disposed between a connection point of the transistor pair and the actuator.

Abstract: A printing method and apparatus is disclosed wherein the printhead has a linear array of nozzles oriented in an axis, and drops of a liquid are printed at a particular location from first and second nozzles of the printhead at a first location. In an embodiment, the nozzles are arranged in groups, each group of nozzles being used to superpose spots of a particular liquid at a different location. A further method is described wherein the printhead is triggered by transferring printing triggers from a processing module to a printhead at print intervals representative of a plurality of fixed units of spatial displacement of the printhead. The present invention is particularly advantageous for the cycling of print nozzles, superposition of spots in linear arrays and fine control of spot positioning. The invention has particular application in the field of printing DNA microarrays.

Abstract: A liquid jet apparatus includes a plurality of nozzles provided to a liquid jet head, an actuator provided corresponding to each of the nozzles, and drive unit that applies a drive pulse to the actuator, wherein the drive unit includes correction value storing unit that stores a drive pulse application timing correction value corresponding to the number of actuators to be driven, and drive pulse application timing correction unit that corrects the drive pulse application timing using the drive pulse application timing correction value corresponding to the number of actuators to be driven stored in the correction value storing unit.

Abstract: A liquid ejection method includes generating drive signals including ejection pulses, and applying the ejection pulses to an element that performs an operation for causing a liquid to be ejected. The element is provided corresponding to a nozzle. The nozzle causes the liquid to be ejected toward a targeted object. The generated drive signals are a first drive signal and a second drive signal. The first and second drive signals are generated simultaneously. The first drive signal includes a first ejection pulse for causing a liquid to be ejected to a targeted object, and the second drive signal includes a second ejection pulse for causing the liquid that has thickened in viscosity to be ejected outside the targeted object. When the nozzle is located above the targeted object, the first ejection pulse is applied to the element, and when the nozzle is located outside the targeted object, the second ejection pulse is applied to the element.

Abstract: A printing apparatus is capable of printing images by ejecting ink droplets from nozzles. The printing apparatus includes: a drive signal generation unit which generates ejectable drive pulses for ejecting ink droplets based on image data indicating the number of ink droplets for each pixel, and outputs the ejectable drive pulses to the nozzles; and a temperature measuring unit which measures the temperature of the ink. The drive signal generation unit also outputs non-ejectable drive pulses to the nozzle when the ink temperature is lower than a predetermined temperature. The non-ejectable drive pulses are generated and output in order that even when the nozzle is driven by the non-ejectable drive pulses, no ink droplet is ejected. It is therefore possible to provide, without substantially increasing the production cost, the printing apparatus which can elevate the ink temperature irrespective of the print coverage when the ink temperature is low.

Abstract: A method for setting up a condition for a drive signal in a liquid ejection head that includes a plurality of linearly-arranged nozzles and driving elements provided for each of the nozzles, includes: calculating an average value or a median value of ejection rates for each nozzle relating to a supply of the drive signal under a plurality of conditions; classifying the plurality of nozzles into a plurality of groups based on the average value or the median value of the ejection rates; calculating a proper condition for the drive signal corresponding to each group based on a statistical value of the ejection rate relating to the group; and selecting one proper condition among proper conditions corresponding to the groups so as to set the selected proper condition for each nozzle.

Abstract: A serial signal for generating a plurality of recording waveform signals is transmitted serially from a signal transmission circuit to a head river. A serial-parallel converting circuit parallely converts the serial signal and generates a plurality of kinds of the recording waveform signals. A selector in the head driver selects a predetermined recording waveform signal from the plurality of kinds of the recording waveform signals based on a selection signal corresponding to each of actuators. The drive pulse of the selected recording waveform signal is outputted to a recording head and carries out dot recording.

Abstract: An ink jet record apparatus has a record head that ejects ink from a nozzle to form an image on a record medium, a maintenance portion that executes maintenance operation to prevent drying of the nozzle at regular time intervals when image formation is not executed, a first mode setting portion that sets the ink jet record apparatus on a usual power mode in which usual power is consumed or a power saving mode in which power supply to other parts than those required for returning to the usual power mode is reduced, and a second mode setting portion that sets the ink jet record apparatus on a permission mode in which the maintenance operation and predetermined operation other than the maintenance operation are permitted or an inhibition mode in which the predetermined operation is inhibited although the maintenance operation is permitted during the power saving mode.

Abstract: An aspect of the invention provides an inkjet printer including: an inkjet head and a controller. The inkjet head moves relative to a recording medium to perform printing. The inkjet head includes, a flow path unit including plural pressure chambers respectively communicating with plural ink ejection ports that ejects ink droplets toward the recording medium, and a piezoelectric actuator configured to take a first state and a second state. The controller supplies a drive pulse signal to the piezoelectric actuator in order to repeat an operation in which the piezoelectric actuator transits from the first state to the second state and returns to the first state, for enabling the corresponding ink ejection port to eject a plurality of ink droplets. The controller supplies the drive pulse signal so that timings of the transition and the return satisfy some relationships.

Abstract: An inkjet recording head substrate having an electrothermal transducer for generating thermal energy used to discharge ink and a drive element for driving the electrothermal transducer mounted thereon includes a first circuit portion for outputting selection signals for selecting the electrothermal transducer to be driven at a amplitude level of a second voltage higher than a first voltage based on an input signal of the amplitude level of the first voltage, a second circuit portion for inputting the selection signals from the first circuit portion and controlling the drive element corresponding to the electrothermal transducer to be driven based on the selection signals subject to the second voltage, and a plurality of signal lines for transmitting the selection signals between the first and second circuit portions.

Abstract: A liquid jet apparatus according to the present invention includes a drive waveform generator adapted to generate a drive waveform signal, a modulator adapted to execute pulse modulation on the drive waveform signal, a digital power amplifier adapted to power-amplify the modulated signal, on which the pulse modulation is executed by the modulator, with a pair of switching elements push-pull coupled with each other, a lowpass filter adapted to smooth the amplified digital signal obtained by the power-amplification of the digital power amplifier, and a modulation period adjustment circuit adapted to adjust a modulation period of the pulse modulation of the modulator in accordance with a reset signal forming a basis of timing for driving the actuator.

Abstract: A inkjet printhead that has a wafer substrate with a fluid ejection surface, and an array of drop ejectors for ejecting drops of printing fluid onto a media substrate, the array being formed on the fluid ejection surface of the wafer substrate. Each drop ejector has a nozzle defining an aperture through which the drops are ejected, an actuator for ejecting drops through the nozzle and, a drive transistor for energizing the actuator with a drive pulse. The area of the drive transistor projected onto the fluid ejection surface is less than 37 times the area of the aperture of the nozzle.

Abstract: A liquid-droplet jetting apparatus such as an ink-jet printer makes a meniscus of an ink in a nozzle vibrate by applying a no-jetting drive pulse which does not jet the ink. An operation of outputting two no-jetting drive pulses in one cycle is repeated for 100 to 150, and then stopped for 100 to 150 cycles. A pulse width Tp of the no-jetting drive pulses, an interval Tw between two no-jetting drive pulses, and a time AL in which a pressure wave in an ink channel is propagated one way are set to be in a range 0.1 AL?Tp?0.2 AL, and 0.2 AL?Tw?4.5 AL. Accordingly, it is possible to prevent assuredly, thickening of a liquid such as an ink in the nozzle, and to reduce a generation of a defect in jetting of a liquid droplet.

Abstract: An array type inkjet printer system having a print head with a plurality of nozzles formed therein in the horizontal scan direction includes a resolution adjusting unit for reducing a resolution in the horizontal scan direction of print data by a predetermined rate; a rendering unit for rendering the print data according to the resolution adjusted by the resolution adjusting unit; and a scaler for scaling the size of the rendered print data to be in correspondence to a resolution of the array type inkjet printer. Therefore, the number of operative nozzles at one time can be reduced, and therefore power consumption is reduced. This in turn opens up the possibility to use a small-sized, low-cost power supply unit.

Abstract: Methods and apparatuses for optimizing the energy supplied to a print head heater are disclosed. A resistance associated with the print head heater or actuator is determined. A range of fire pulse values is determined based at least in part on the determined resistance and a velocity optimization procedure is executed based at least in part on the determined range of fire pulse values. An optimal fire pulse for the print head heater is selected based at least in part on the results of the velocity optimization procedure.