Method for driving liquid droplet discharge head, liquid droplet discharge device, and program

Abstract

This method for driving a droplet ejection head 23 that discharges droplets from a nozzle 21 and performs a recording operation on a recording medium has: an addition step S1 for adding a third drive pulse P3 in a pause period T1 between a first drive pulse P1 and a second drive pulse P2 immediately preceding the first drive pulse P1 in a common drive waveform P00 including a plurality of drive pulses; a determination step S2 for selecting one or a plurality of drive pulses from a common drive waveform P01 and determining a discharge drive pulse that discharges a droplet from the nozzle 21; and a discharge step S3 for discharging, in a single drive cycle T, a droplet from the nozzle 21 using the discharge drive pulse determined in the determination step.

Description

Technical Field

[0001] The present invention relates to a method for driving a droplet ejection head, a droplet ejection apparatus, and a program.Background Art

[0002] There has been known a droplet ejection apparatus configured to eject droplets onto recording surfaces of recording media to record images. The droplet ejection apparatus ejects droplets from nozzles of a droplet ejection head at appropriate timings based on image data.

[0003] In the droplet ejection head, a multi-drive method is realized. The multi-drive method is a method in which a multi-drive signal including a plurality of drive pulses is applied to a droplet ejection head to continuously eject droplets. According to this method, one dot having different sizes can be formed on a recording surface.

[0004] Specifically, as described in Patent Documents 1 and 2, for example, dots having different sizes can be formed by selecting and combining desired drive pulses from a common drive waveform including a plurality of drive pulses.Citation ListPatent Literature

[0005] Patent Document 1: JP 2006-224471A Patent Document 2: JP 2011-143682A Summary of InventionTechnical Problem

[0006] Incidentally, there is a case where it is desired to form a dot of a new size by adding a drive pulse not included in the common drive waveform. However, as shown in FIG. 7, when a drive pulse is further added to the common drive waveform, the entire cycle is extended by the waveform length of the added drive pulse. As a result, the drive frequency is lowered, resulting in reduced productivity.

[0007] The present invention has been made in view of such circumstances. It is an object of the present invention to provide a method for driving a droplet ejection head, a droplet ejection apparatus, and a program that do not reduce productivity even when a drive pulse is newly added.Solution to Problem

[0008] In order to solve the problem described above, the invention recited in claim 1 is a method for driving a droplet ejection head that performs a recording operation on a recording medium by using a common drive waveform including a plurality of drive pulses within a drive cycle to eject a droplet from a nozzle, the method comprising: an addition step of adding a third drive pulse in a pause period between a first drive pulse and a second drive pulse immediately preceding the first drive pulse in the common drive waveform; a determination step of determining an ejection drive pulse for ejecting the droplet from the nozzle by selecting one or a plurality of drive pulses from the common drive waveform to which the third drive pulse has been added in the addition step; and an ejection step of ejecting the droplet from the nozzle in the drive cycle using the ejection drive pulse determined in the determination step.

[0009] The invention recited in claim 2 is the method according to claim 1, wherein the first drive pulse is a last drive pulse within the drive cycle, and an interval between a start of a rise of the second drive pulse and a start of a rise of the first drive pulse is 3.8 AL or more and 4.2 AL or less.

[0010] The invention recited in claim 3 is the method according to claim 1 or 2, wherein a droplet ejected by the first drive pulse and the second drive pulse and a droplet ejected by the third drive pulse are different in ejection speed.

[0011] The invention recited in claim 4 is the method according to claim 1 or 2, wherein a droplet ejected by the first drive pulse and the second drive pulse and a droplet ejected by the third drive pulse are different in ejection amount.

[0012] The invention recited in claim 5 is the method according to claim 1 or 2, wherein a droplet ejected by the first drive pulse and a droplet ejected by the second drive pulse are merged into a single droplet before landing on the recording medium.

[0013] The invention recited in claim 6 is the method according to claim 1 or 2, wherein a droplet having a first size is ejected by the first drive pulse and the second drive pulse, and a droplet having a second size smaller than the first size is ejected by the third drive pulse.

[0014] The invention recited in claim 7 is the method according to claim 1 or 2, wherein the addition step includes adding the third drive pulse that corresponds to an image to be formed on the recording medium by the recording operation.

[0015] The invention recited in claim 8 is a droplet ejection apparatus comprising: a droplet ejection head that performs a recording operation on a recording medium by using a common drive waveform including a plurality of drive pulses within a drive cycle to eject a droplet from a nozzle; an addition section that adds a third drive pulse in a pause period between a first drive pulse and a second drive pulse immediately preceding the first drive pulse in the common drive waveform; a determination section that determines an ejection drive pulse for ejecting the droplet from the nozzle by selecting one or a plurality of drive pulses from the common drive waveform to which the third drive pulse has been added by the addition section; and an ejection section that ejects the droplet from the nozzle in the drive cycle using the ejection drive pulse determined by the determination section.

[0016] The invention recited in claim 9 is a program causing a computer of a droplet ejection apparatus including a droplet ejection head that performs a recording operation on a recording medium by using a common drive waveform including a plurality of drive pulses within a drive cycle to eject a droplet from a nozzle to perform: an addition step of adding a third drive pulse in a pause period between a first drive pulse and a second drive pulse immediately preceding the first drive pulse in the common drive waveform; a determination step of determining an ejection drive pulse for ejecting the droplet from the nozzle by selecting one or a plurality of drive pulses from the common drive waveform to which the third drive pulse has been added in the addition step; and an ejection step of ejecting the droplet from the nozzle in the drive cycle using the ejection drive pulse determined in the determination step.Advantageous Effects of Invention

[0017] According to the present invention, even when a drive pulse is newly added, productivity is not reduced.Brief Description of Drawings

[0018] [FIG. 1] This is a block diagram of an inkjet recording apparatus. [FIG. 2] This is a schematic diagram of pressure chambers and nozzles viewed in an axial direction of the nozzles, showing changes in the pressure chambers in response to drive pulses. [FIG. 3] This is a schematic diagram illustrating an action of an ink droplet ejected from a nozzle. [FIG. 4] This is a drive control method of a droplet ejection head according to the present embodiment. [FIG. 5] This is a diagram showing an example of a common drive waveform. [FIG. 6] This is a diagram showing an example of the common drive waveform to which a third drive pulse has been added. [FIG. 7] This is a diagram showing an example of a case where a new waveform is added to a common drive waveform in a conventional droplet ejection head. Description of Embodiments

[0019] An embodiment of the present invention will be described below with reference to the drawings. The following description exemplifies one embodiment of the present invention and does not limit the present invention.[Overall Configuration of Inkjet Recording Apparatus]

[0020] FIG. 1 is a block diagram illustrating a functional configuration of an inkjet recording apparatus 1 including inkjet heads 23.

[0021] Each of the inkjet heads 23 is a droplet ejection head to which a drive setting method according to the present embodiment is applied. The inkjet recording apparatus 1 is a droplet ejection apparatus including the droplet ejection head.

[0022] The inkjet recording apparatus 1 includes a conveyance section 10, a recording operation section 20, a cleaning section 30, a controller 40, a storage section 50, a communication section 60, an operation reception section 70, a display part 80, and a power supply section 90.(Conveyor)

[0023] The conveyance section 10 moves a recording medium on which an image is to be recorded. The conveyance section 10 causes the recording medium to face a recording range of the recording operation section 20.

[0024] The conveyance section 10 includes, for example, a conveyance motor 11 that pulls out a long recording medium wound up in a roll shape at a predetermined speed. The recording medium is, for example, textile, but may be paper or another material.(Recording Operation Section)

[0025] The recording operation section 20 ejects ink onto the recording medium to record an image.

[0026] The recording operation section 20 includes inkjet heads 23. Each of the inkjet heads includes a large number of nozzles 21 that are aligned in a predetermined pattern and eject ink, and piezoelectric elements 22. In the inkjet recording apparatus 1, a plurality of inkjet heads 23 is disposed along a conveyance direction of the recording medium.

[0027] The recording operation section 20 includes a head drive section 24. The head drive section 24 outputs a drive pulse for expanding or contracting each piezoelectric element 22 based on control of the controller 40. The piezoelectric element 22 deforms an ink channel (pressure chamber) 25 that supplies ink to the corresponding nozzle 21 in accordance with deformation caused by the drive pulse to apply pressure fluctuation to the ink.

[0028] In detail, as shown in FIG. 2, the controller 40 deforms side walls 26 of the pressure chamber 25 that communicate with the nozzle 21 by applying an ejection drive pulse, which is a drive pulse for ejecting a droplet, to the piezoelectric element 22.

[0029] Then, as shown in FIG. 3, a meniscus 27 formed adjacent to an ejection opening of the nozzle 21 is shaken, and an ink droplet (main droplet) 28 is separated from the meniscus 27 to be ejected.

[0030] At this time, a satellite droplet 29, which is a minute droplet, may be ejected after the main droplet 28.(Cleaning Section)

[0031] Returning to FIG. 1, the cleaning section 30 cleans a nozzle surface of the inkjet head 23 where openings of the nozzles 21 are aligned.

[0032] The cleaning section 30 includes a wiping member 32 that wipes ink and solidified matter thereof attached to the nozzle surface. The cleaning section 30 further includes a drive section 31 that operates the wiping member 32. The wiping member 32 is not particularly limited, but is, for example, a nonwoven fabric that absorbs ink or a blade-like resin member that scrapes off a solid.(Controller)

[0033] The controller 40 is a processor that integrally controls the entire operation of the inkjet recording apparatus 1.

[0034] The controller 40 includes, for example, a central processing unit (CPU) 41 and a random-access memory (RAM) 42. The CPU 41 performs arithmetic operations and various kinds of control processing. The RAM 42 provides a working memory space for the CPU 41 and stores temporary data.

[0035] The controller 40 executes predetermined programs to function as an addition section, a determination section, and an ejection section.

[0036] The controller 40, as an addition section, performs control by adding a predetermined drive pulse to a common drive waveform P00.

[0037] Details of the common drive waveform P00 and the addition control will be described later.

[0038] In addition, the controller 40, as a determination section, selects one or a plurality of drive pulses according to a dot size from a common drive waveform P01, and generates a waveform selection signal for determining an ejection drive pulse for ejecting ink from each nozzle 21.

[0039] Specifically, the waveform selection signal is, for example, a negative logic pulse signal. When the waveform selection signal is logically summed with the common drive waveform P01, the one or the plurality of drive pulses is selected, and the other drive pulses are removed.

[0040] Furthermore, the controller 40 as an ejection section controls the head drive section 24 so as to output, to the piezoelectric element 22, the ejection drive pulse determined by the controller 40 as a determination section. Then, the ink is ejected from the nozzle 21.(Storage Section)

[0041] The storage section 50 stores image data to be recorded, processed data thereof, other setting data, and programs. The image data may be stored in, for example, a dynamic random-access memory (DRAM) that can temporarily store a large amount of data and output the data at high speed. In addition, the setting data and programs are stored in a non-volatile memory such as a flash memory and / or a hard disk drive (HDD).

[0042] In this way, the setting data can be stored even when the supply of power to the inkjet recording apparatus 1 is stopped.

[0043] The storage section 50 also stores the common drive waveform P01 to which a third drive pulse P3 described later has been added by the controller 40 (refer to FIG. 6) and the common drive waveform P00 before the addition (refer to FIG. 5).(Communicator)

[0044] The communication section 60 controls transmission and reception of data with an external device in accordance with a predetermined communication standard, for example, the transmission control protocol / internet protocol (TCP / IP).

[0045] The communication section 60 may be connected to a local area network (LAN) and connectable to the external Internet via a router. The communication section 60 may be directly connectable to a peripheral device via a universal serial bus (USB) cable connected to a USB terminal.(Operation Reception Section)

[0046] The operation reception section 70 receives an input operation by a user and outputs the received content to the controller 40 as an input signal.

[0047] The operation reception section 70 includes, for example, a touch screen and a push button switch. The touch screen may be positioned to overlap a display screen of the display part 80, and the operation content may be specified in synchronization with the display content on the display screen.(Display Part)

[0048] The display part 80 displays a status and a selection menu to the user.

[0049] The display part 80 includes, for example, a display screen and an indicator (lamp). For example, the indicator may be used to indicate the presence or absence of power supply or the presence or absence of an operational abnormality by a light emitting diode (LED) lamp.

[0050] The display part 80 includes, for example, a liquid crystal display and can display various characters and figures in a dot matrix on the display screen.(Power Supply Section)

[0051] The power supply section 90 supplies power from a power source to the inkjet recording apparatus 1.[Drive Method in Recording Operation]

[0052] Next, a method for driving the inkjet head 23 in a recording operation will be described.

[0053] As illustrated in FIG. 4, the method for driving the inkjet head 23 according to the present embodiment includes an addition step S1, a determination step S2, and an ejection step S3.(Addition Step)

[0054] First, in the addition step S1, as shown in FIG. 6, the controller 40 newly adds an ejection drive pulse to the common drive waveform P00 as shown in FIG. 5.(Common Drive Waveform)

[0055] FIG. 5 illustrates the common drive waveform P00 within one drive cycle T according to an example of the present invention. The drive cycle T corresponds to the drive cycle of the inkjet head 23 for forming one dot on a recording medium during the recording operation. That is, the inkjet head 23 performs a multi-drive in the drive cycle T to form one dot.

[0056] In the addition step S1, an ejection drive pulse (hereinafter, referred to as a third drive pulse) P3 is added in the pause period T1 in the common drive waveform P00. The pause period T1 refers to a period between the start of the rise of a predetermined drive pulse (hereinafter, first drive pulse) P1 and the completion of the fall of a drive pulse (hereinafter, second drive pulse) P2 immediately preceding the first drive pulse P1.

[0057] The addition of the third drive pulse P3 by the controller 40 is based on an instruction by the user of the inkjet recording apparatus 1, for example, via the operation reception section 70. That is, for example, in response to an image formation instruction from the user, when the controller 40 determines that a dot that cannot be drawn by the drive pulses in the common drive waveform P00 is included, the third drive pulse P3 is added.

[0058] The third drive pulse P3 only needs to have a pulse width Pw that can be applied during the pause period T1. In other words, the third drive pulse P3 only needs to have a pulse width Pw that is narrower than the pause period T1 (hereinafter, referred to as Condition 1). In addition, the third drive pulse P3 only needs to have a voltage value at which ink can be ejected (hereafter, Condition 2).

[0059] Specifically, the controller 40 determines whether a dot of a desired size can be formed by any one of the drive pulses or a combination of a plurality of the drive pulses in the common drive waveform P00.

[0060] If the controller 40 determines that the desired size is smaller than the size of the dot that can be formed by the drive pulse(s) in the common drive waveform P00, the controller 40 generates the third drive pulse P3 and adds the third drive pulse P3 in the pause period T1. The third drive pulse P3 is a small droplet waveform that satisfies Conditions 1 and 2 and that is capable of forming a dot of the desired size.

[0061] If the controller 40 determines that the desired size is greater than the size of the dot that can be formed by the drive pulse(s) in the common drive waveform P00, the controller 40 generates the third drive pulse P3 and adds the third drive pulse P3 in the pause period T1. The third drive pulse P3 is a large droplet waveform that satisfies Conditions 1 and 2 and that is capable of forming a dot of the desired size by a combination with one or a plurality of the drive pulses in the common drive waveform P00.

[0062] Note that the addition of the third drive pulse P3 is not limited to addition by the controller 40. Any suitable third drive pulse P3 may be formed and added by a user's instruction.

[0063] The third drive pulse P3 may be a pulse group formed by a plurality of drive pulses including an ejection drive pulse.

[0064] In particular, when the third drive pulse P3 is a pulse group, the third drive pulse P3 may include a tail-cutting pulse or a suppression pulse that suppresses reverberant vibration of the meniscus 27 after droplet ejection. After application of the ejection drive pulse for ejecting the main droplet 28, the main droplet 28 can be formed into a small droplet by applying a tail-cutting pulse that is an ejection drive pulse for cutting off a tail of the main droplet 28, which is a columnar droplet, at an early stage.

[0065] Note that in the present invention, as illustrated in FIG. 5, the time from the start of the rise to the start of the fall in one trapezoidal drive pulse is defined as the pulse width Pw.

[0066] When the first drive pulse P1 is the last drive pulse in the common drive waveform P00, an interval T2 between the start of the rise of the first drive pulse P1 and the start of the rise of the second drive pulse P2 is preferably set to a predetermined value. The predetermined value is 3.8 AL (acoustic length; half of acoustic resonance frequency) or more and 4.2 AL or less.

[0067] When the interval T2 is within the above range, the negative pressure in the pressure chamber 25 immediately before the contraction element of the second drive pulse P2 is applied (at time t1) is suppressed. As a result, ejection of the satellite droplet 29 can be reduced. In addition, the pulse width Pw of an ejection drive pulse is usually around 1 AL. Therefore, any third drive pulse P3 can be added to the pause period T1.(Determination Step)

[0068] After adding the third drive pulse P3, the controller 40 generates a waveform selection signal for forming the desired dot in the determination step S2. Then, the controller 40 determines an ejection drive pulse. To be more specific, the controller 40 takes a logical sum of the common drive waveform P01 and the waveform selection signal and selects a drive pulse to be used for ink ejection from a group of drive pulses.(Ejection Step)

[0069] After determining the ejection drive pulse, the controller 40 causes the head drive section 24 to apply the selected drive pulse to the piezoelectric element 22, to eject ink from the nozzle 21.

[0070] As described above, the head drive section 24 applies, to the piezoelectric element 22, the ejection drive pulse for expanding or contracting the pressure chamber 25 and then returning the pressure chamber 25 to its original state under the control of the controller 40. Through the above-described operation, pressure fluctuation is imparted to the ink, and one ink droplet is ejected from the nozzle 21.[Effects of Embodiment]

[0071] As described above, the present invention includes the addition step S1 of adding the third drive pulse P3 in the pause period T1 between the first drive pulse P1 and the second drive pulse P2 in the common drive waveform P00. The method further includes the determination step S2 of determining an ejection drive pulse for ejecting a droplet from the nozzle 21 by selecting one or a plurality of drive pulses from the common drive waveform P01. The method further includes an ejection step S3 of ejecting the droplet from the nozzle 21 in one drive cycle T using the ejection drive pulse determined in the determination step S2.

[0072] Therefore, the drive cycle T does not change before and after the addition of the third drive pulse P3, and the drive frequency does not decrease. Therefore, image recording can be performed without reducing productivity.

[0073] Furthermore, in the present invention, the interval T2 between the start of the rise of the second drive pulse P2 and the start of the rise of the first drive pulse P1 is 3.8 AL or more and 4.2 AL or less.

[0074] According to the configuration, it is possible to reduce the ejection of the satellite droplet 29. Furthermore, any suitable third drive pulse P3 can be added in the pause period T1.

[0075] Further, in the present invention, by performing a multi-drive, a droplet ejected by the first drive pulse P1 and a droplet ejected by the second drive pulse P2 are merged into a single droplet before landing on a recording medium.

[0076] According to the configuration, one dot having different sizes can be formed by a droplet ejected by the first drive pulse P1 and the second drive pulse P2.[Other Configurations]

[0077] Although the present invention has been described in detail based on the embodiment, the present invention is not limited to the above-described embodiment. Of course, various modifications are possible within the scope of the invention described in the claims and their equivalents.

[0078] For example, although FIG. 5 illustrates the common drive waveform P00 including four drive pulses including the fourth drive pulse P4 and the fifth drive pulse P5 as well as the first drive pulse P1 and the second drive pulse P2, the present invention is not limited thereto. In the present invention, the common drive waveform P00 only needs to include at least two or more drive pulses.

[0079] Further, in FIG. 5 and FIG. 6, for ease of explanation, the rise from the initial voltage and the fall to the initial voltage of each trapezoidal wave are shown with lengths that are easy to understand, but the present invention is not limited thereto.

[0080] The rise and fall times relative to the duration of the drive voltage may be suitably determined. In addition, the rise and fall of the trapezoidal wave are not limited to a linear (first-order) voltage change and may be an exponential rise.

[0081] FIG. 5 illustrates the case where the first drive pulse P1 is the last drive pulse within the drive cycle T, but the present invention is not limited thereto. Any drive pulse other than the first drive pulse within the drive cycle T can be the first drive pulse P1.

[0082] The speed of ink ejected by the first drive pulse P1 and the second drive pulse P2 may be the same as or different from the ejection speed of ink ejected by the third drive pulse P3.

[0083] Similarly, the amount of ink ejected by the first drive pulse P1 and the second drive pulse P2 may be the same as or different from the amount of ink ejected by the third drive pulse P3.

[0084] However, it is preferable that the ink ejected by the first drive pulse P1 and the second drive pulse P2 is different from the ink ejected by the third drive pulse P3 in terms of ejection speed or amount. This configuration allows for more variation in droplet ejection. For example, a droplet of a first size is ejected by the first drive pulse P1 and the second drive pulse P2, and a droplet of a second size smaller than the first size is ejected by the third drive pulse P3.

[0085] In particular, when a gap between the inkjet head 23 and the recording medium is large, high-precision image recording is possible by high-speed ejection using the third drive pulse P3.

[0086] In the above description, the first drive pulse P1 is an ejection drive pulse, but the present invention is not limited thereto.

[0087] For example, the first drive pulse P1 may be a suppression pulse that suppresses reverberant vibration of the meniscus 27 after droplet ejection by the second drive pulse P2.

[0088] Furthermore, as described above, the storage section 50 may store the common drive waveform P01. When the common drive waveform P01 is stored in the storage section 50, a selection step of selecting any one of the common drive waveforms P00 and P01 may be executed. When the selection step is executed, the determination step S2 and the ejection step S3 are executed using the selected common drive waveform P00 or P01.

[0089] Furthermore, ink ejected from the inkjet head 23 is not particularly limited. The ink may be an ultra violet (UV) ink or a solder resist (SR) ink. In addition, the present invention is not limited to the inkjet recording apparatus 1 and may be various droplet ejection apparatuses that eject droplets of liquid other than ink from the nozzles 21.

[0090] In the above description, an example in which a hard disk, a semiconductor non-volatile memory, or the like is used as a computer-readable medium for the program according to the present invention has been disclosed, but the medium is not limited to this example. As another computer-readable medium, a portable recording medium such as a CD-ROM can be applied. Furthermore, a carrier wave is also applied as a medium for providing data of the program according to the present invention via a communication line.Industrial Applicability

[0091] The present invention can be used for a method for driving a droplet ejection head, a droplet ejection apparatus, and a program that do not reduce productivity when a drive pulse is newly added.Reference Signs List

[0092] 1 inkjet recording apparatus (droplet ejection apparatus) 21 nozzle 23 inkjet head (droplet ejection head) 25 pressure chamber 40 controller (addition section, determination section, ejection section) 70 operation reception section P00 common drive waveform (common drive waveform before the third drive pulse is added) P01 common drive waveform (common drive waveform to which the third drive pulse has been added) P1 first drive pulse P2 second drive pulse P3 third drive pulse Pw pulse width T drive cycle T1 pause period T2 interval (interval between the rise of the second drive pulse and the start of the rise of the first drive pulse)

Claims

1. A method for driving a droplet ejection head that performs a recording operation on a recording medium by using a common drive waveform including a plurality of drive pulses within a drive cycle to eject a droplet from a nozzle, the method comprising: an addition step of adding a third drive pulse in a pause period between a first drive pulse and a second drive pulse immediately preceding the first drive pulse in the common drive waveform; a determination step of determining an ejection drive pulse for ejecting the droplet from the nozzle by selecting one or a plurality of drive pulses from the common drive waveform to which the third drive pulse has been added in the addition step; and an ejection step of ejecting the droplet from the nozzle in the drive cycle using the ejection drive pulse determined in the determination step.

2. The method according to claim 1, wherein the first drive pulse is a last drive pulse within the drive cycle, and an interval between a start of a rise of the second drive pulse and a start of a rise of the first drive pulse is 3.8 AL or more and 4.2 AL or less.

3. The method according to claim 1 or 2, wherein a droplet ejected by the first drive pulse and the second drive pulse and a droplet ejected by the third drive pulse are different in ejection speed.

4. The method according to claim 1 or 2, wherein a droplet ejected by the first drive pulse and the second drive pulse and a droplet ejected by the third drive pulse are different in ejection amount.

5. The method according to claim 1 or 2, wherein a droplet ejected by the first drive pulse and a droplet ejected by the second drive pulse are merged into a single droplet before landing on the recording medium.

6. The method according to claim 1 or 2, wherein a droplet having a first size is ejected by the first drive pulse and the second drive pulse, and a droplet having a second size smaller than the first size is ejected by the third drive pulse.

7. The method according to claim 1 or 2, wherein the addition step includes adding the third drive pulse that corresponds to an image to be formed on the recording medium by the recording operation.

8. A droplet ejection apparatus comprising: a droplet ejection head that performs a recording operation on a recording medium by using a common drive waveform including a plurality of drive pulses within a drive cycle to eject a droplet from a nozzle; an addition section that adds a third drive pulse in a pause period between a first drive pulse and a second drive pulse immediately preceding the first drive pulse in the common drive waveform; a determination section that determines an ejection drive pulse for ejecting the droplet from the nozzle by selecting one or a plurality of drive pulses from the common drive waveform to which the third drive pulse has been added by the addition section; and an ejection section that ejects the droplet from the nozzle in the drive cycle using the ejection drive pulse determined by the determination section.

9. A program causing a computer of a droplet ejection apparatus including a droplet ejection head that performs a recording operation on a recording medium by using a common drive waveform including a plurality of drive pulses within a drive cycle to eject a droplet from a nozzle to perform: an addition step of adding a third drive pulse in a pause period between a first drive pulse and a second drive pulse immediately preceding the first drive pulse in the common drive waveform; a determination step of determining an ejection drive pulse for ejecting the droplet from the nozzle by selecting one or a plurality of drive pulses from the common drive waveform to which the third drive pulse has been added in the addition step; and an ejection step of ejecting the droplet from the nozzle in the drive cycle using the ejection drive pulse determined in the determination step.

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