LIQUID EJECTION DEVICE, INFORMATION PROCESSING DEVICE, GENERATION METHOD, STORAGE MEDIUM, AND PROGRAM

Abstract

In a configuration in which liquid is supplied to a plurality of nozzles from a common liquid chamber, the influence of crosstalk is reduced. [Solution] A liquid ejection device comprising a plurality of nozzles that eject liquid supplied through a common liquid chamber, a plurality of energy elements provided in the plurality of nozzles that generate energy to eject liquid from corresponding nozzles, and a generation means that generates control data for the plurality of energy elements, wherein when each energy element is driven based on first control data, the generation means calculates the change in characteristics that will be caused in the nozzle corresponding to the second energy element, which is the energy element that is driven later, due to the liquid pressure fluctuation in the common liquid chamber caused by driving the first energy element, which is the energy element that is driven first, and generates second control data that adjusts the energy generated by the second energy element based on the calculated change in characteristics.

Description

[Technical Field]

[0001] The present invention relates to a liquid ejection device. [Background technology]

[0002] Liquid ejection devices that manufacture organic EL elements used as light-emitting elements in displays and quantum dot color conversion layers used for color conversion require stable droplet landing positions and ejection volumes. When manufacturing displays with numerous organic EL elements arranged on a substrate, variations in droplet landing positions and ejection volumes can lead to variations in the film thickness of the functional layer depending on the pixel, resulting in non-uniform light-emitting characteristics. Furthermore, when manufacturing quantum dot color conversion layers, variations in droplet landing positions and ejection volumes can lead to non-uniform optical characteristics of the formed quantum dot color conversion layer depending on the pixel or region. One known cause of these issues is the effect of crosstalk within the ejection head. In an ejection head that supplies liquid from a common liquid chamber to multiple nozzles, the ejection pressure propagates through the common liquid chamber, potentially resulting in crosstalk. Patent Document 1 discloses a technique for modulating ejection energy to reduce the effects of crosstalk. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2001-287347 Summary of the Invention [Problem to be solved by the invention]

[0004] The technology of Patent Document 1 leaves room for improvement in terms of reducing the effects of crosstalk.

[0005] The present invention provides a technique for reducing the influence of crosstalk in a configuration in which liquid is supplied to a plurality of nozzles from a common liquid chamber. [Means for solving the problem]

[0006] According to the present invention, a plurality of nozzles that eject liquid supplied via a common liquid chamber; a plurality of energy elements provided in the plurality of nozzles and generating energy for ejecting liquid from the corresponding nozzles; generating means for generating control data for the plurality of energy elements; A liquid ejection device comprising: The generating means calculating a change in characteristics that is caused in a nozzle corresponding to a second energy element that is driven later by a liquid pressure fluctuation in the common liquid chamber that is caused by driving the first energy element that is the energy element that is driven first when each energy element is driven based on the first control data; generating second control data that adjusts the energy generated by the second energy element based on the calculated change in the characteristics; A liquid ejection device characterized by the above features is provided. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide a technique for reducing the influence of crosstalk in a configuration in which liquid is supplied to a plurality of nozzles from a common liquid chamber. [Brief explanation of the drawings]

[0008] [Figure 1] 1A and 1B are a plan view and a side view of a liquid ejection device according to an embodiment of the present invention. [Figure 2] FIG. 2A is a block diagram of a control system of the liquid ejection device, and FIG. 2B is a diagram showing an example of the configuration of a measurement unit. [Figure 3] (a) and (b) are a plan view and a side view of the substrate. [Figure 4] 1(a) to 1(c) are explanatory diagrams of a discharge head. [Figure 5] FIG. 3 is a block diagram of a drive processing unit. [Figure 6] FIG. 1 is a diagram showing a circuit of an analog switch. [Figure 7]Waveform diagram of three types of drive signals. [Figure 8] (a) and (b) are diagrams showing the propagation of pressure waves due to crosstalk. [Figure 9] 6(a) to 6(c) are graphs showing examples of calculation results of the amount of fluctuation in the discharge speed. [Figure 10] 10 is a flowchart showing an example of generating control data. [Figure 11] 10A and 10B are diagrams showing examples of nozzles in use and ejection timing information. [Figure 12] FIG. 10 is a diagram showing the distribution of the amount of fluctuation in the ejection speed after correction. [Figure 13] 10 is a flowchart showing an example of generating control data. [Figure 14] 10A is a diagram showing offset of the fluctuation amount of the ejection speed, and FIG. 10B is a diagram showing the distribution of the impact deviation amount when the ejection timing is offset. [Figure 15] (a) is a conceptual diagram of direct and indirect waves, and (b) is a diagram showing an example of path calculation for reflected waves. [Figure 16] 10 is a flowchart showing another example of generating control data. [Figure 17] 10 is a flowchart showing another example of generating control data. [Figure 18] 10(a) to 10(c) are diagrams showing the distribution of the fluctuation amount of the discharge velocity. [Figure 19] 10A and 10B are diagrams showing examples of sets of drive signals. [Figure 20] 10 is a flowchart showing another example of generating control data. [Figure 21] FIG. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the scope of the invention claimed. Although multiple features are described in the embodiments, not all of these multiple features are necessarily essential to the invention, and multiple features may be combined arbitrarily. Furthermore, in the accompanying drawings, the same reference numerals are used to designate the same or similar components, and redundant explanations will be omitted.

[0010] <Embodiment 1> <Outline of liquid ejection device> 1(a) and 1(b) are a plan view and a side view showing the configuration of a liquid ejection device 1 according to one embodiment of the present invention. The liquid ejection device 1 is a recording device that ejects ink from an ejection head 100 onto a substrate 11 to record functional elements such as organic EL elements and quantum dot color conversion layers. The liquid ejection device 1 may also be a recording device that ejects ink onto a recording medium such as paper to record an image. In each figure, arrows X and Y indicate horizontal directions that are orthogonal to each other, and arrow Z indicates the vertical direction.

[0011] The liquid ejection device 1 includes a stage 10 that supports a substrate 11. The substrate 11 is set at a predetermined position on the stage 10, and the stage 10 is fixed to a base 9 of the device. The liquid ejection device 1 also includes a transport unit 321 that moves the ejection head 10.

[0012] The transport unit 321 includes a main scanning guide rail 5 extending along the main scanning direction (X direction), a sub-scanning guide rail 7 extending along the sub-scanning direction (Y direction), and a carriage 4 that moves on the main scanning guide rail 5. The main scanning guide rail 5 moves in the X direction guided by the sub-scanning guide rail 7, and the sub-scanning guide rail 7 is supported on a base 9 by a support member 8. The drive mechanism of the transport unit 321 can be, for example, a ball screw mechanism or a belt transmission mechanism using a motor as a drive source.

[0013] The ejection head 100 is fixed to the carriage 4. As will be described later, the ejection head 100 has a plurality of nozzles (liquid ejection ports) on a surface (nozzle surface) facing the substrate 11. By driving the transport unit 321, the ejection head 100 can freely move within a plane parallel to the XY plane at a height spaced a predetermined distance from the substrate 11 in the Z direction.

[0014] In this embodiment, the position of the substrate 11 is fixed and the ejection head 100 is moved, but it is sufficient that the ejection head 100 and the substrate 11 can move relative to each other, and it is also possible to have a configuration in which the ejection head 100 is fixed and the substrate 11 is moved.

[0015] Ink is supplied to the ejection head 100 from the ink tank 50 through an ink supply path 75. The ink supply path 75 is formed by a pipe such as a flexible tube.

[0016] The liquid ejection device 1 has a cleaning unit 322 for maintaining the ejection performance of the ejection head 100. The cleaning unit 322 includes a cap 55 that covers the nozzle surface of the ejection head 100. The ejection performance can be maintained by ejecting ink from the ejection head 100 into the cap 55. The cleaning unit 322 may also include a pump that sucks ink from the ejection head 100 through the cap 55. Waste ink discharged from the ejection head 100 into the cap 55 is flowed into a waste ink tank 60 and collected.

[0017] The liquid ejection device 1 also includes a measurement unit 332 that measures the ejection performance of each nozzle of the ejection head 100. The ejection performance is, for example, the ejection amount and ejection speed of the liquid.

[0018] The control system of the liquid ejection device 1 will now be described. The control system of the liquid ejection device 1 is composed of an electric circuit having at least one processor and at least one storage device. Figure 2(a) is a block diagram showing a simplified view of the control system of the liquid ejection device 1.

[0019] The CPU 301 reads and executes a program for system control stored in the ROM 302, and controls the entire liquid ejection device 1 in accordance with the program. The program is loaded into the RAM 303, which is used as a work area. In other words, the RAM 303 temporarily stores data necessary for the processing executed by the CPU 301, input data, and the like.

[0020] The CPU 301 can also communicate with a host 400 via an interface 304. The host 400 is, for example, a user's PC, and instructs the CPU 301 to execute the printing operation together with printing data for the functional elements to be formed on the substrate 11.

[0021] The CPU 301 also controls the operations of the transport unit 321, cleaning unit 322, etc. Furthermore, the CPU 301 controls the printing operation of the ejection head 100 through the image processing unit 310 and drive processing unit 311. The image processing unit 310 also performs predetermined image processing on the printing data. That is, the image processing unit 309 converts input printing data such as the pixel size of the substrate 11, pixel spacing, and film thickness required for each pixel into control data for controlling the ejection head 100. The drive processing unit 311 then causes the ejection head 100 to eject ink droplets based on the control data.

[0022] Furthermore, the measurement unit 332 can measure the ejection volume and ejection speed of ink droplets ejected from the ejection head 100 under the control of the CPU 301. Based on the measurement results, the CPU 301 can control the ejection volume and ejection speed of ink droplets ejected from the ejection head 100 via the image processing unit 310 and the drive processing unit 311.

[0023] 2(b) is a diagram showing an example of the configuration of the measurement unit 332. The measurement unit 332 of this embodiment is an optical sensor that optically detects flying droplets. The measurement unit 332 is an optical sensor that includes a light-emitting element 3321 and a light-receiving element 3322 that are spaced apart in the X direction. The measurement unit 332 includes a housing 3320 that forms a groove 3320a that opens upward, and the light-emitting element 3321 and the light-receiving element 3322 are supported by the housing 3320 so as to sandwich the groove 3320a.

[0024] The light emitting element 3321 emits a light beam 3324, and the light receiving element 3322 receives the light beam 3324 emitted by the light emitting element 3321. The sensor circuit 3323 detects the amount of light received by the light receiving element 3322. The light beam 3324 defines the detection position of the droplet, and when a droplet passes through the light beam 3324, the amount of light received by the light receiving element 3322 changes. This allows the droplet to be detected.

[0025] The sensor circuit 3323 is provided with a current-to-voltage conversion circuit that converts the current flowing according to the amount of light received by the light receiving element 3322 into a voltage signal and outputs it, and an amplifier circuit for amplifying the level of the ink droplet detection signal. Furthermore, it is provided with a clamp circuit to eliminate the effects of output saturation and a decrease in S / N ratio caused by fluctuations in the level of the ink droplet ejection detection signal due to disturbances. The clamp circuit maintains the level of the signal output from the amplifier circuit at a predetermined value (clamp voltage) until just before ejection is observed.

[0026] These circuits detect minute changes in the amount of received light, such as the passage of ink droplets, and therefore ensure the level of the detection signal. When an ink droplet passes through the light beam 3324 of the measurement unit 332, the amount of light received by the light receiving element 3322 changes. From the detection results, the amount and speed of ink discharged from the nozzle can be measured.

[0027] <Substrate> The substrate 11 will now be described. FIGS. 3(a) and 3(b) are plan and side views of the substrate 11. The substrate 11 is a glass substrate for displays, with a thickness of, for example, 0.7 mm to 1.1 mm. The bank material 12 is a partition wall to prevent the functional ink from flowing or mixing colors, and is preferably made of a light-blocking material. The thickness of the bank material 12 is, for example, approximately 2 μm to 30 μm. The bank 100 refers to a bathtub-shaped area surrounded by the substrate 11 and the bank material 12, and can be filled with the required amount of functional ink droplets. The banks 100 are arranged in an R, G, and B array. A specific bank may be specified by the ink color (R, G, B) and XY coordinates. For example, the bank 99 in FIG. 3(a) may be written as B[2][0].

[0028] <Discharge head> An example of the configuration of the ejection head 100 will be described. The ejection head 100 is independent for each ink color, and there are three ink colors (three heads) in total: R, G, and B. However, since the structure and ejection control are the same apart from the ink color, the ejection head for B (Blue) ink will be described here as a representative example.

[0029] 4(a) to 4(c) are explanatory diagrams of the ejection head 100. FIG. 4(a) is a perspective view (transparent view) of the ejection head 100. Ink is supplied to the ejection head 100 from an ink tank 50 (FIG. 1(a)) through an ink supply path 75. A pressurized supply method or a head difference supply method can be used for ink supply. The supplied ink is temporarily stored in a rectangular parallelepiped common liquid chamber 140 inside the ejection head 100. A nozzle plate 120 is provided directly below the common liquid chamber 140. The nozzle plate 120 has individual supply ports 101 that communicate with the nozzles, the number of which is the same as the number of nozzles, and ink is supplied from the common liquid chamber 140 to the individual supply ports 101.

[0030] FIG. 4(b) is a plan view (perspective view) of the ejection head 100, and is a perspective view of the nozzle plate 120, with the supply path 75 and common liquid chamber 140 not shown. The nozzle plate 120 has a plurality of nozzles 102 formed therein. The nozzles 102 are ejection ports that eject ink. The nozzle plate 120 has a total of four nozzle rows, rows A to D, formed therein. Each nozzle 102 is provided with an energy element 110, an individual flow path 130, and an individual supply port 110. For ease of explanation, FIG. 4(b) shows eight nozzles 102 per row. However, the number of nozzles 102 per row is, for example, 256. In this case, the ejection head 100 has a total of 1,024 nozzles 102. The nozzles 102 in each row are designated 0, 1, ... from the left in the Y direction.

[0031] The nozzle pitch (spacing) in each nozzle row in the Y direction is, for example, 150 dpi. Adjacent nozzle rows are arranged, for example, offset by 600 dpi in the Y direction. Therefore, the nozzle pitch when viewed as a whole of the ejection head 100 is 600 dpi.

[0032] FIG. 4(c) is a cross-sectional view of the ejection head 100, showing a cross section along line X'-X" in FIG. 4(b). The ink in the common liquid chamber 140 is supplied to the nozzle 102 via the individual supply port 101 and the individual liquid chamber 130.

[0033] A pulsed voltage is applied between the electrodes 111a and 111b via the drive processing unit 311, driving the energy element 110. The energy element 110 generates energy to eject liquid from the corresponding nozzle 102. In this embodiment, the energy element 110 is a piezoelectric element that vibrates when a voltage is applied. As a result, the volume of the individual liquid chamber 130 changes slightly, and the resulting contraction pressure pressurizes the ink in the individual liquid chamber 130, causing an ink droplet to be ejected through the nozzle 102.

[0034] <Drive processing unit> Figure 5 is a block diagram of the drive processing unit 311. For convenience, Figure 5 shows only the circuits corresponding to four energy elements 110. However, in reality, the drive processing unit 311 includes circuits corresponding to all of the nozzles 102.

[0035] The drive processing unit 311 supplies a drive signal to each energy element 110 of the ejection head 100, thereby driving each energy element 110 and causing liquid to be ejected from each nozzle 102. The drive processing unit 311 is electrically connected to one end of the energy element 110, and the other end is common and grounded. The drive processing unit 311 in this embodiment is capable of generating multiple types of energy with different magnitudes for each energy element 110. Specifically, the drive processing unit 311 adjusts the energy generated by the energy element 110 by selectively supplying a drive signal (drive voltage) corresponding to each type of generated energy to the energy element 110.

[0036] The drive processing unit 311 has a data control circuit 201, a voltage generation circuit 202, and a drive circuit 203. The data control circuit 201 is a control unit that controls the voltage generation circuit 202 and the drive circuit 203 to adjust the drive voltages supplied to each of the energy elements 110. Specifically, the data control circuit 201 controls the voltage generation circuit 202 by outputting an operation command to the voltage generation circuit 202. The data control circuit 201 also generates a logic signal according to control data and correction data for the energy elements 110 corresponding to the recording data, and controls the drive circuit 203 by outputting the logic signal to the drive circuit 203.

[0037] The correction data is data for correcting variations in the ejection characteristics (relationships of the ejection amount and ejection speed with respect to the drive voltage) due to various fluctuation factors, and adjusting the ejection amount or ejection speed of droplets ejected from the nozzles 102. The fluctuation factors include fluctuations in the ejection amount and ejection speed of droplets due to crosstalk, which will be described later.

[0038] Specifically, the correction data is data for correcting the drive voltage supplied to the energy element 110 for ejecting droplets for each nozzle 102 and for each recording dot (droplet). The logic signals output from the data control circuit 201 include a control data signal DATA, a clock signal CLK, a latch signal LT, and a timing signal SEL.

[0039] In this embodiment, the control data signal DATA is 8-bit serial data for each energy element 110 (per nozzle). The timing signal SEL indicates the timing for switching the drive voltage supplied to the energy element 110. In this embodiment, the timing signal SEL can switch the drive voltage for each recording dot (droplet). That is, in this embodiment, the drive voltage can be switched for each nozzle 102 and for each recording dot (droplet).

[0040] The voltage generation circuit 202 is a generation unit that generates a plurality of drive signals with different waveforms in accordance with an operation command from the data control circuit 201, and outputs the plurality of drive signals to the drive circuit 203. In this embodiment, the voltage generation circuit 202 generates three types of drive signals 1 to 3 with different waveforms. The drive circuit 203 drives the energy element 110 of the ejection head 100 by supplying a drive voltage to the energy element 110 in accordance with the logic signal from the data control circuit 201 and the drive signals 1 to 3 from the voltage generation circuit 202.

[0041] The drive circuit 203 includes a shift register 204, a latch circuit 205, a decoder 206, and a switch unit 207. The shift register 204 receives the control data signal DATA from the data control circuit 201 in synchronization with the clock signal CLK, converts the control data signal DATA into parallel control data, and outputs the control data. The control data is 8 bits of data per energy element 110.

[0042] The latch circuit 205 latches the control data output from the shift register 204 in synchronization with the latch signal LT. A decoder 206 is provided for each energy element 110 (for each nozzle 102). Of the control data latched by the latch circuit 205, each decoder 206 receives 2-bit data indicating the drive voltage to be supplied to the energy element 110 corresponding to that decoder 206. Each decoder 206 outputs a switch signal that switches the state (on / off) of the switch unit 207 in accordance with the input 2-bit data. At this time, the decoder 206 switches the output switch signal in accordance with the timing signal SEL from the data control circuit 201.

[0043] A switch unit 207 is provided for each energy element 110 (for each nozzle 102). A switch signal from the decoder 206 corresponding to the same energy element 110 is input to each switch unit 207. In response to the input switch signal, each switch unit 207 outputs (supplies) one of the drive signals 1 to 3 from the voltage generation circuit 202 as a drive voltage to the energy element 110 of the ejection head 100. Each switch unit 207 has analog switches 207a to 207c. The analog switches 207a to 207c switch their states (on / off) in response to the switch signal from the decoder 206, thereby switching between outputting and stopping output of each of the drive signals 1 to 3.

[0044] 6 is a diagram showing the circuit of the analog switch. The analog switch 207a has an NMOS (N-type MOS transistor) 221, a PMOS (P-type MOS transistor) 231, and an inverter 235. The NMOS 221 and the PMOS 231 are connected in parallel with each other. Specifically, the sources of the NMOS 221 and the PMOS 231 are commonly connected to an input terminal 241 to which the drive signal 1 is input, and the drains of the NMOS 221 and the PMOS 231 are commonly connected to the energy element 110.

[0045] The gate of NMOS 221 is connected to a control terminal 251 to which a switch signal is input, and the gate of PMOS 231 is connected to the control terminal 251 via an inverter 235. When the switch signal input to the control terminal 251 is at H level, both NMOS 221 and PMOS 231 are on, that is, the analog switch 107a is on, and the drive signal 1 input to the input terminal 241 is supplied as a drive voltage to the energy element 110. On the other hand, when the switch signal is at L level, both NMOS 221 and PMOS 231 are off, that is, the analog switch 207a is off, and the supply of the drive signal 1 to the energy element 110 is stopped.

[0046] The analog switch 207b also has an NMOS 222, and the source of the NMOS 222 is connected to an input terminal 242 to which the drive signal 2 is input. The drain of the NMOS 222 is connected to the energy element 110. The gate of the NMOS 222 is connected to a control terminal 252 to which a switch signal is input. When the switch signal input to the control terminal 252 is at H level, the NMOS 222 is turned on, that is, the analog switch 207b is turned on, and the drive signal 2 input to the input terminal 252 is supplied to the energy element 110 as a drive voltage. When the switch signal is at L level, the NMOS 222 is turned off, that is, the analog switch 207b is turned off, and the supply of the drive signal 2 to the energy element 110 is stopped. Note that the description of the analog switch 207c is the same as that of the analog switch 207b, so it will not be repeated here.

[0047] As described above, one of the three types of drive signals 1 to 3 to be supplied to the energy element 110 can be switched by an analog switch.

[0048] <Drive signal> FIG. 7 is a waveform diagram of three types of drive signals 1 to 3 generated by the voltage generation circuit 202. Drive signal 2 is a reference signal. Drive signal 2 supplies a reference drive voltage to the energy element 110, causing the nozzle 102 to eject droplets having a predetermined standard amount of ejection volume and ejection speed. Drive signal 3 is a drive signal used to reduce the ejection volume and ejection speed from the standard amount. Drive signal 1 is a drive signal used to increase the ejection volume and ejection speed from the standard amount.

[0049] Within one ejection cycle, drive signals 1 to 3 include different voltage periods where the voltages are different from each other and same voltage periods where the voltages are approximately equal to each other. Furthermore, drive signal 1 has the largest amplitude, or the difference between the maximum and minimum values ​​of the drive voltage, and drive signal 3 has the smallest. Generally, the larger the amplitude of the drive voltage, the greater the displacement of the energy element 110, resulting in an increase in the ejection volume and ejection speed. By using drive signal 1 as the drive voltage supplied to the energy element 110, it is possible to increase the ejection volume and ejection speed compared to when drive signal 2 is used. Conversely, by using drive signal 3, it is possible to decrease the ejection volume and ejection speed compared to when drive signal 2 is used. In this way, by using drive signals 1 to 3 appropriately according to the ejection characteristics, it is possible to change the ejection volume and ejection speed of ink droplets.

[0050] <Variations in ejection characteristics due to the effects of crosstalk> The ejection head 100 of this embodiment is configured so that liquid is supplied to a plurality of nozzles 102 from a common liquid chamber 140. Because the plurality of nozzles 102 are in communication with each other via the common liquid chamber 140, fluctuations in liquid pressure caused by driving the energy element 110 of one nozzle 102 are propagated to the other nozzles 102. This crosstalk causes the ejection characteristics of the other nozzles 102 to fluctuate.

[0051] More specifically, a drive signal is sent from the CPU 301 to the ejection head 100 via the drive processing unit 311, and the energy element 110 vibrates, causing a change in the pressure in the individual liquid chamber 130 to eject ink droplets. The pressure fluctuation caused by the ejection of droplets reaches not only the individual liquid chamber 130 in question, but also neighboring individual liquid chambers via the common liquid chamber 140 at the speed of sound in the ink.

[0052] The pressure fluctuations affect the meniscus surface of the nozzle 102 in the neighboring individual liquid chamber 130, causing it to vibrate. The frequency of the meniscus vibration at this time depends on the natural frequency determined by the individual liquid chamber 130 and the physical properties of the ink. Pressure fluctuations caused by droplet ejection from any nozzle 102 propagate to the individual liquid chambers 130 of neighboring nozzles 102, causing the ejection performance of the neighboring nozzles 102 to fluctuate. This is the effect of crosstalk. In this embodiment, we focus on the ejection speed as an ejection characteristic of the nozzle 102.

[0053] The terms used for the explanation will be defined below. An "influence nozzle" is a nozzle 102 that propagates a pressure wave to the ink in the common liquid chamber 140 by driving the corresponding energy element 110. In other words, it is a nozzle 102 whose corresponding energy element 110 is driven first and exerts an influence. The term "influence nozzle" may also be used to mean the driving of the energy element 110 corresponding to that nozzle 102. The energy element 110 corresponding to the influence nozzle 102 can also be called the influence energy element 110.

[0054] The "nozzle of interest" is a nozzle 102 whose ejection characteristics fluctuate due to the influence of pressure waves from other nozzles 102. In other words, it is the nozzle 102 that is affected when the corresponding energy element 110 is subsequently driven. The energy element 110 that corresponds to the nozzle of interest 102 can also be called the energy element 110 of interest.

[0055] In reality, various nozzles 102 eject ink at various times, so each nozzle 102 can be both an affected nozzle and a focused nozzle. In other words, whether a nozzle is an affected nozzle or a focused nozzle is determined by distinguishing the nozzle at a certain time.

[0056] FIG. 8(a) is a diagram showing the propagation of pressure waves due to crosstalk. The affected nozzle here is the third nozzle 102 in column C (hereinafter abbreviated as nozzle C3; the same rule may be used for other nozzles 102). Consider a situation in which an ejection signal for one dot is input from the CPU 301 via the drive processing unit 311 to the energy element 110 corresponding to nozzle C3. The energy element 110 of nozzle C3 vibrates, and as a result, the volume of the individual liquid chamber 130 changes. The ink in the individual liquid chamber 130 is pressurized, and an ink droplet is ejected from nozzle C3.

[0057] At this time, the pressure fluctuation caused by droplet ejection does not remain within the individual liquid chamber 130 of the C3 nozzle, but propagates to the common liquid chamber 140 through the supply port 101. The pressure wave propagates from the supply port 101 of the C3 nozzle to the common liquid chamber 140 generally as follows.

[0058] First, the propagation speed of the pressure wave depends on the speed of sound Vc [m / s] in the ink, which is determined by the ink's bulk modulus, density, etc. The speed of sound Vc in the ink is, for example, 1000 to 1500 [m / s]. Next, the propagation direction of the pressure wave, as shown in the figure, propagates in the form of a spherical wave from the supply port 101 of the C3 nozzle within a radius r.

[0059] The propagation path of the pressure wave is roughly classified into a "direct wave" and a "reflected wave". The "direct wave" is a pressure wave that is emitted through the supply port 101 of the C3 nozzle, propagates through the common liquid chamber 140 at the speed of sound in the ink, and reaches the supply port 101 of the target nozzle 102 without being reflected by the wall surface inside the common liquid chamber 140 even once. The reflected wave is a pressure wave that is emitted through the supply port 101 of the C3 nozzle, propagates through the common liquid chamber 140 at the speed of sound in the ink, is reflected by the wall surface inside the common liquid chamber 140 at least once, and reaches the supply port 101 of the target nozzle 102. In this embodiment, an example will be described in which the reflected wave is not considered and only the direct wave is considered.

[0060] Equations 1 and 2 in FIG. 21 are equations that represent the amount of variation in the ejection speed by which the influencing nozzle 102 affects the target nozzle 102. Here, consider the case where a pressure wave emitted from the supply port 101 of an arbitrary i-th influencing nozzle 102 reaches the supply port 101 of the target nozzle 102.

[0061] Let the straight-line distance between the supply ports 101 of the influencing nozzle 102 and the target nozzle 102 be L [μm], and the speed of sound in the ink be Vc [m / s]. Also, let the elapsed time from when the energy element 110 corresponding to the influencing nozzle 102 starts vibrating until the energy element 110 of the target nozzle 102 starts vibrating be t [μsec].

[0062] Since the pressure wave emitted from the influencing nozzle 102 propagates in a spherical wave shape with a radius r at the speed of sound Vc in the ink, the distance traveled by the pressure wave at time t is represented by r = Vc × t. The inequality t < L / Vc shown in Equation 1 indicates the range of time t when the pressure wave emitted from the influencing nozzle 102 has not yet reached the target nozzle 102.

[0063] The amount of variation in the ejection speed Δvi on the left side of Equation 1 is the amount of variation in the ejection speed [m / s] that occurs in the target nozzle 102 due to crosstalk caused by an arbitrary i-th influencing nozzle 102. The conditional expression of Equation 1: t < L / Vc indicates that the pressure wave has not reached the target nozzle 102. Therefore, the amount of variation in the ejection speed Δv = 0.

[0064] The condition in Equation 2: t≧L / Vc indicates that the pressure wave has reached the nozzle 102 of interest. On the right-hand side of Equation 2, A is the amplitude coefficient, D is the attenuation coefficient, T is the phase shift [μsec], and λ1 is the characteristic wavelength [μm]. C1 and C2 are constants. The amplitude coefficient A1 is an expression that is inversely proportional to the variable distance r, and represents the attenuation of the pressure wave due to the spherical wave. Because the transmission time of the pressure wave differs depending on the variable distance r, the phase shift T represents the corresponding phase shift. To summarize the above, Equation 2 is the product of the amplitude coefficient that attenuates inversely proportional to the distance r, the attenuation term that attenuates as a function of elapsed time t, and the vibration term that oscillates as a function of elapsed time t.

[0065] A method for obtaining Equation 2 will now be described. It is difficult to accurately measure minute pressure changes in the individual liquid chambers 130 due to the influence of crosstalk. Therefore, Equation 2 can be obtained by observing the change Δvi in ​​the ejection velocity due to the influence of crosstalk.

[0066] Specifically, an observation device capable of measuring the ejection speed of ink droplets is prepared using a high-speed camera, a strobe, etc. Two nozzles 102 (an influential nozzle and a target nozzle) are ejected simultaneously, and the ejection speed of droplets from the target nozzle 102 is measured. After that, the ejection timing of the target nozzle 102 is delayed by a small time Δt relative to the ejection timing of the influential nozzle 102, and each variation Δv in the ejection speed of the ink droplets ejected from the target nozzle 102 is measured.

[0067] The measurement results are graphed, for example, with the horizontal axis representing the ejection timing deviation Δt [μsec] and the vertical axis representing the ejection velocity fluctuation Δv [m / s]. From this graph, the amount of ejection velocity fluctuation Δv of the target nozzle 102 due to the crosstalk effect from the affected nozzle 102 can be obtained.

[0068] Furthermore, a similar experiment is conducted for two nozzles (the affected nozzle and the target nozzle) with different distances L. This makes it possible to measure the dependency of the distance r on the amount of fluctuation Δv in the discharge velocity. Equation 2 can be obtained using the method described above.

[0069] Next, the nozzle of interest 102 may be affected by crosstalk of various amplitudes at various timings from multiple influencing nozzles 102. This is because the ejection timing differs for each nozzle 102 in the first place, and the physical distance between the nozzle of interest and the influencing nozzles 102 differs. It is necessary to take into account the fact that there may be multiple influencing nozzles 102 that affect the nozzle of interest 102.

[0070] Figure 8(b) is a conceptual diagram showing the propagation of pressure waves from multiple influencing nozzles 102. In the example shown in the figure, there are a total of three influencing nozzles 102: nozzle B5, nozzle C1, and nozzle D2. The hemispherical lines show the propagation of pressure waves from each influencing nozzle 102. The difference in the radius of the hemisphere represents the difference in ejection timing, and the larger the radius, the longer the elapsed time t from ejection.

[0071] 8(b), the nozzle 102 of interest is designated as nozzle C3. At the timing shown in the figure, it can be seen that nozzle C3 receives superimposed pressure waves from the three affected nozzles 102, namely nozzle B5, nozzle C1, and nozzle D2.

[0072] 21 is an equation that represents the amount of fluctuation in the discharge speed (Δvall on the left side) that multiple influencing nozzles 102 have in affecting the nozzle of interest 102. The right side is an equation that calculates the amount of fluctuation in the discharge speed that a total of N nozzles 102 equipped in the discharge head 100 have in affecting the nozzle of interest 102, and is a calculation equation that sums up the ΔV obtained by sequentially changing i in equation 2.

[0073] The meaning of this formula is that pressure waves emitted from multiple influencing nozzles 102 overlap at the target nozzle 102, and the amount of fluctuation in the ejection velocity at the target nozzle 102 is expressed as their sum. In other words, the fluctuation in the ejection velocity of the target nozzle 102 is an additive effect of the influences from the multiple influencing nozzles 102. By using formula 3, even if there are multiple influencing nozzles 102 that cause crosstalk effects, it is possible to calculate the amount of fluctuation (Δvall) in the ejection velocity of any target nozzle 102 without having to worry about the amplitude difference or phase shift.

[0074] Figures 9(a) to 9(c) are graphs showing examples of the calculation results of Equations 2 and 3. The contents explained using Equations 1 to 3 will be supplemented with reference to Figures 9(a) to 9(c). In the graphs of Figures 9(a) to 9(c), the horizontal axis represents elapsed time t [μsec], and the vertical axis represents the amount of fluctuation Δv [m / s] in the ejection velocity of the nozzle 102 of interest. Note that the nozzle 102 of interest in Figures 9(a) to 9(c) is the 107th nozzle 102 in row C (nozzle C107).

[0075] The waveform P01 in Figure 9(a) is the amount of fluctuation Δv in the discharge velocity of the target nozzle C107 when the affected nozzle is nozzle C106, calculated based on equations 1 and 2. Note that various constants were values ​​obtained in advance through experiments. The interpretation of this graph will be explained using point P01a on the waveform P01 as an example.

[0076] The affected nozzle 102 starts a discharge operation (vibration of the energy element 101) at elapsed time t = 0.0 [usec]. Next, assume that the nozzle of interest 102 starts a discharge operation (vibration of the energy element 101) at elapsed time t = 10.0 [usec]. When the nozzle of interest 102 discharges under conditions that are not affected by crosstalk (i.e., when discharging as a single nozzle), the discharge speed Vtyp is 5.0 [m / s].

[0077] However, as a result of the influence of crosstalk from the affected nozzle 102, the ejection speed of the nozzle of interest 102 fluctuates, and the graph shows that the amount of fluctuation Δv is +0.1 m / s at point P01a (elapsed time 10.0 usec). In other words, the ejection speed of the nozzle of interest 102 (nozzle C107) affected by crosstalk is Vtyp + ΔV = 5.1 m / s. Of course, if the ejection start timing of the affected nozzle 102 and the nozzle of interest 102 differs, the amount of fluctuation Δv will also differ. As explained in Equation 2, the graph also confirms that the influence of the ejection speed fluctuation Δv decreases as the elapsed time t increases due to the time decay term.

[0078] The waveform P02 in Figure 9(a) is a calculation based on Equations 1 and 2 of the fluctuation amount Δv in the discharge velocity of the nozzle 102 of interest (nozzle C107) when the affected nozzle 102 is nozzle C103. The nozzle-to-nozzle distance L (distance between supply ports) between the affected nozzle 102 and the nozzle 102 of interest is 677 [um], which is four times larger than that of the example of waveform P01. Compared to waveform P01, the amplitude (vertical axis) of the fluctuation amount Δv due to the influence of crosstalk in waveform P02 is reduced to approximately one-quarter. This is because, as explained in Equation 2, the energy of a pressure wave propagating as a spherical wave with radius r attenuates at 1 / r.

[0079] The graph also confirms that, as a result of the inter-nozzle distance L being four times larger, the fluctuation amount Δv of the ejection velocity is also reduced to one-quarter. Furthermore, compared to waveform P01, waveform P02 shows that, although the period of the fluctuation amount Δv itself remains unchanged, the phase is shifted in the delayed direction. This is because, as explained in Equation 2, the phase shift T is proportional to the inter-nozzle distance L. Explained qualitatively, crosstalk pressure waves propagate at the speed of sound using the ink inside the ejection head 100 as a medium. Therefore, the greater the distance between the target nozzle 102 and the affected nozzle 102, the longer it takes for the pressure wave to propagate, resulting in a corresponding shift in the delayed direction.

[0080] The waveform P03 in Figure 9(a) is the ejection velocity fluctuation Δv of the target nozzle 102 (nozzle C107) calculated based on Equations 1 and 2 when the affected nozzle 102 is nozzle C95. The inter-nozzle distance L (supply port distance) is 2031 [um]. The amplitude of waveform P03 is approximately 1 / 8 that of waveform P01. It can also be seen that the phase shift is larger. Note that in the range of elapsed time t up to approximately 1 [usec], the ejection velocity fluctuation Δv is 0 [m / s]. This is the region indicated by Equation 1, and because the inter-nozzle distance L is large, this is a region where the pressure wave propagating at the speed of sound in the ink has not yet arrived.

[0081] Figure 9(b) is a graph showing waveform P04 obtained by calculating the sum of waveforms P01 to P03 in Figure 9(a) according to Equation 3. Qualitatively, waveform P04 is a graph of the elapsed time and the fluctuation amount Δv of the ejection speed of nozzle C107 of interest when the affected nozzles C106, C103, and C95 simultaneously start ejection operations (vibration of diaphragm 101 begins) at elapsed time t = 0.

[0082] Because the vibration period of waveform P04 is determined by the natural period, it remains unchanged from waveforms P01 to P03, but it can be seen that the phase shift in the time direction and amplitude change as a result of the summation. As explained in Equation 3, when there are multiple influencing nozzles 102, the effects of crosstalk can be superimposed. In other words, when speed fluctuations with a positive sign and speed fluctuations with a negative sign overlap, they cancel each other out and weaken each other, and when speed fluctuations with the same sign overlap, they strengthen each other.

[0083] Figure 9(c) shows only waveform P04. At point P04a (elapsed time t = 10.0 [usec]), it can be seen that the fluctuation amount ΔV in the ejection velocity of the nozzle of interest 102 is +0.08 [m / s] as a result of the influence of crosstalk from the three affected nozzles 102. In other words, the ejection velocity of the nozzle of interest 102 influenced by crosstalk is Vtyp + ΔV = 5.08 [m / s].

[0084] As explained above, if the inter-nozzle distance L [um] between the affected nozzle 102 and the target nozzle 102 and the elapsed time t [usec] from the start of ejection of the affected nozzle 102 are known, the total amount of fluctuation Δvall in the target nozzle 102 can be calculated using equations 1 to 3.

[0085] <Example of generating control data for energy elements> An example of generating control data for the energy element 110 in which the effects of crosstalk are suppressed will be described. In this embodiment, original control data (called primary control data) that does not take the effects of crosstalk into consideration is corrected to generate control data in which the effects of crosstalk are suppressed. Correcting the control data is also called dynamic pulse correction. Dynamic pulse correction corrects the ejection speed by adjusting the drive pulse of the energy element 110 for each recording dot. This solves the problem caused by the effects of crosstalk, i.e., fluctuations in the ejection speed for each recording dot, resulting in variations in the landing position. Note that a recording dot is a unit dot formed on the substrate 11 by ink ejected from the nozzle 102, and is sometimes called an ejected dot.

[0086] The recording operation of the liquid ejection device 1 is performed by alternately repeating an operation of ejecting ink while moving the ejection head 100 in the main scanning direction relative to the substrate 11 (recording scan) and a movement operation of moving the ejection head 100 in the sub-scanning direction relative to the substrate 11. The main scanning direction is the X direction, and the sub-scanning direction is the Y direction. Recording scans are sometimes called scans. Depending on the recording range of the substrate 11, the recording operation may be completed in a single scan and may not involve a movement operation. In the device configuration of this embodiment, the effects of crosstalk do not extend across multiple scans. Therefore, it is sufficient to consider the effects of crosstalk for all recording dots in one scan.

[0087] Fig. 10 is a flowchart showing an example of control data generation processing, which is an example of processing executed by CPU 301. The processing in Fig. 10 is executed for one scan's worth of data among the primary control data. If the primary control data is for a printing operation that requires multiple scans, the same processing is repeated for each scan.

[0088] In S101, information on nozzles to be used and ejection timing for all recording dots for one scan of the primary control data is obtained from the RAM 303. The RAM 303 stores information on all recording dots for at least one scan.

[0089] FIG. 11 shows some of the acquired information in table format. This table assigns one row of information to each recording dot. The information includes the bank color and bank numbers X and Y to identify the bank. The information also includes the scan number indicating which scan it is, the head number identifying the ejection head 100, the column number and nozzle number identifying the nozzle 102, and the time indicating the ejection timing. For example, the information in the first row of FIG. 11 specifies that the ejection operation will be performed during the 37th scan for the bank color = B, bank number X = 259, and bank number Y = 371. The nozzle 102 at that time is the nozzle with nozzle column number C and nozzle number 84 of the ejection head 100 with head number 0, and the ejection timing is 30070.83 μsec.

[0090] Note that the ejection timing is set to the origin (=0 μsec) at the time when one scan begins. However, in the correction calculations described below, it is sufficient to know the inter-nozzle distance L (supply port distance) and the relative time difference in ejection timing between print dots, so absolute time is not essential.

[0091] 10, for each recording dot, the fluctuation amount Δv that each influencing nozzle 102 imparts to the target nozzle 102 used for ejection is calculated using Equations 1 and 2. It is assumed that the drive signal for each energy element 110 is a signal of the standard amount (drive signal 2).

[0092] In S103, a calculation is performed to superimpose the effects of crosstalk. As mentioned above, it is known that the effects of crosstalk can be superimposed. In other words, if a component that increases velocity and a component that decreases velocity arrive at the same time, they weaken each other, and if increasing components or decreasing components overlap, they strengthen each other. For each printing dot, the effects of crosstalk from the multiple influencing nozzles 102 are calculated using Equation 3 to determine the sum Δvall of the fluctuation amounts Δv that each influencing nozzle 102 imparts to the target nozzle 102 used to eject that dot.

[0093] Figure 12 is a graph showing the effect of crosstalk on all recording dots for one scan based on the calculation results of S103. The horizontal axis is the amount of fluctuation in ejection speed Δvall [m / s] due to the effect of crosstalk, and the vertical axis is the number of recording dots. The dashed line 500a is the result of the overlap calculation of the effect of crosstalk in S103 of Figure 10. It can be seen that the graph shape roughly follows a normal distribution. The reason for this distribution is that, as mentioned above, the ejection timing of each recording dot varies and the distance between nozzles also varies, so there are relatively many dots that weaken the ejection speed fluctuations and relatively few dots that strengthen the speed fluctuations.

[0094] Returning to Figure 10, in S104, dynamic pulse correction processing is executed. The meaning of "dynamic" in dynamic pulse correction is as follows: for each recording dot, the speed fluctuation of the nozzle of interest 102 caused by the ejection of the affected nozzle 102 is calculated, and then an appropriate correction pulse is applied to the energy element 110 of the nozzle of interest 102, thereby reducing the speed fluctuation. This is called dynamic pulse correction because it applies a correction pulse according to the speed fluctuation, rather than applying a statically determined pulse waveform.

[0095] The drive signal setting process of S104 will be described using Figure 13. First, in S104-01, the maximum value Vmax and minimum value Vmin of the ejection speed fluctuation amount Δvall for one scan are obtained from the calculation result of S103 in Figure 10. The speed fluctuation range is specified using these values. In the following description, as an example, the maximum value Vmax = +0.4 m / s and the minimum value Vmin = -0.5 m / s.

[0096] In S104-02, the speed fluctuation range obtained in S104-01 is divided by the division number N to obtain a division width Td. The division number N is the same as the number of types of drive signals for the energy element 110. When three types of drive signals 1 to 3 are used as in this embodiment, N=3. In this case, Td=(0.4-(-0.5)) / 3=0.3 m / s. In other words, the speed fluctuation range is divided into three increments of 0.3 m / s. Returning to FIG. 12, regions 501 to 503 respectively indicate divided regions. The divided regions 501 to 503 indicate the region on the negative side of the fluctuation amount Δvall (the lower 1 / 3 of the recording dots), the intermediate region (the middle 1 / 3 of the recording dots), and the positive side (the upper 1 / 3 of the recording dots).

[0097] Next, in S104-03, the allocation of dynamic correction pulses to each recording dot is determined, where the type of drive signal to drive the energy element 110 of the nozzle 102 that forms the recording dot is determined.

[0098] First, for a group of recording dots determined to be in the middle third, the variation Δvall is relatively small, so a pulse corresponding to a standard amount of ejection speed is applied as the drive signal for the energy element 110 (S104-05). Specifically, drive signal 2 in FIG. 7 is applied. For a group of recording dots determined to be in the lower third, a pulse that increases the ejection speed beyond the standard amount is applied as the drive signal for the energy element 110. Specifically, drive signal 1 in FIG. 7 is applied. For dots determined to have a speed variation from the upper third, a pulse that decreases the speed is applied as the drive signal for the energy element 110. Specifically, drive signal 3 in FIG. 7 is applied.

[0099] Figure 14(a) is a graph showing the effect of crosstalk on all recording dots for one scan based on the calculation results of S103 before and after the application of dynamic pulse correction. The dashed line 500a in Figure 14(a) represents the distribution of velocity fluctuations before dynamic pulse correction is implemented, and is the same as that shown in Figure 12. The solid line 500b represents the distribution of velocity fluctuations after dynamic pulse correction is implemented. It can be seen that implementing dynamic pulse correction reduces the range of velocity fluctuations for recording dots in one scan. As a result of the reduced range of velocity fluctuations, the impact deviation on substrate 11 can also be reduced.

[0100] The dashed line 500b-1 in Figure 14(a) represents the average value of the fluctuation amount Δvall of all recording dots after dynamic pulse correction. Although the width of the velocity fluctuation distribution has been reduced by dynamic pulse correction, the average value is offset from no fluctuation (Δvall = 0.0 [m / s]). The average offset of all recording dots is approximately -0.08 [m / s]. If this continues, the impact of the recording dots on the substrate 11 will be delayed overall. For this reason, the ejection timing is adjusted in S105 of Figure 10.

[0101] In S105, the ejection timing of all recording dots for one scan is offset uniformly. If the average speed of all recording dots is offset by approximately -0.08 m / s from the design center (nominal value) of the ejection speed, the ejection timing of all recording dots can be uniformly advanced.

[0102] The extent to which the ejection timing should be changed can be calculated using Equation 4 in Figure 21. Specifically, the design center (nominal value) of the droplet ejection speed is vtyp [m / s], the average deviation of the ejection speed of all recording dots from the design center (nominal value) is Δvav [m / s] (signed), and the distance between the ejection head 100 and the substrate 11 is h [m]. The time ΔToffset [sec] (signed) required to offset the ejection timing can be found from Equation 4.

[0103] Figure 14(b) is a graph showing the impact position deviation ΔX [μm] of the recording dots on the substrate 11 in the main scanning direction (X direction) as a result of uniformly offsetting the ejection timing of all recording dots. Line 500c represents the distribution of the impact position deviation ΔX [μm] of the recording dots, and 500c-1 is the average value of the distribution of line 500c. The calculation conditions were h = 1.0 × 10^(-3) [m] and Vtyp = 5.0 [m / s].

[0104] From the line 500c and the line 500c-1, it can be seen that the distribution is generally symmetrical with respect to the point where there is no impact deviation (ΔX=0.0 [μm]) as the center.

[0105] Through the above process, control data is generated by correcting the primary control data with the allocation of control signals 1 to 3 and the offset of the ejection timing. By executing the printing operation using the generated control data, printing can be performed with reduced effects of crosstalk.

[0106] <Embodiment 2> In the second embodiment, dynamic pulse correction is performed taking into consideration not only direct waves but also reflected waves with respect to the influence of crosstalk. As explained in the first embodiment, the influence of crosstalk is the influence of direct waves and reflected waves. In the first embodiment, only direct waves were considered, but in the second embodiment, both direct waves and reflected waves are considered.

[0107] Figure 15(a) is a conceptual diagram of direct waves and reflected waves. Here, the explanation will be given assuming that the affected nozzle 102 is the C2 nozzle and the target nozzle 102 is the B6 nozzle. The direct wave is a pressure wave that arrives from the supply port 101 of the C2 nozzle to the supply port 101 of the B6 nozzle via the shortest path. In contrast, the pressure wave that starts from the supply port 101 of the C nozzle 2, is reflected by one of the wall surfaces that define the rectangular parallelepiped common liquid chamber 140, and arrives at the supply port 101 of the B6 nozzle is called a "reflected wave." The reflected wave can be assumed to be reflected once, twice, three times, ... or up to N times.

[0108] Each time the pressure wave is reflected, it loses energy, and the amplitude of the pressure wave decreases; this is called reflection attenuation. The pressure wave energy lost through reflection attenuation is used to elastically deform the ink and wall surface, and is ultimately dissipated outside the system as thermal energy. If the volume of the common liquid chamber 140 is sufficiently large, accurate calculations are possible with up to N=1 reflections. This is because the wave is diffused as a spherical wave, and the effect of the attenuation of amplitude A (1 / r) is greater than the effect of reflection attenuation. On the other hand, if the volume of the common liquid chamber 140 is very small, the effect of the attenuation of amplitude A (1 / r) is smaller than the effect of reflection attenuation. Therefore, accuracy can be improved by appropriately setting the number of reflections N and performing calculations. FIG. 15(b) is a diagram illustrating an example of calculating the path of a reflected wave. An example will be described below of calculating the path of a reflected wave reflected by the "wall surface on the row A side" out of the five wall surfaces excluding the bottom surface of the common liquid chamber 140 in FIG. 15(a). First, a point of a virtual supply port 101a is set outside the wall of the common liquid chamber 140. This is the point where the "distance between the wall surface on the row A side and the supply port 101 of the B6 nozzle" and the "distance between the wall surface on the row A side and the virtual supply port 101a" are equidistant and shortest. Next, an auxiliary line is drawn from the supply port 101 of the C2 nozzle toward the virtual supply port 101a. The intersection of this auxiliary line and the wall surface on the row A side is designated as PA.

[0109] The distance from the supply port 101 of the C2 nozzle to the intersection PA is L1 [μm], and the distance from the intersection PA to the supply port 101 of the B6 nozzle is L2 [μm]. The total path length L' of the reflected waves from the wall surface on the row A side is L1 + L2. By performing a similar calculation, it is possible to determine the reflected waves from other wall surfaces. Also, while the calculation method for one reflection path has been exemplified here, the total path length of N reflection paths can also be determined by setting multiple virtual points.

[0110] Next, we will explain how to sum up the direct wave and reflected wave due to the influence of crosstalk using Equation 5. Equation 5 in Figure 21 is a calculation formula for calculating the amount of fluctuation Δvi [m / s] in the ejection velocity occurring at the nozzle 102 of interest. Δvi on the left side of Equation 5 is the sum of the velocity fluctuation due to the direct wave and reflected wave of the pressure wave from the i-th affected nozzle 102.

[0111] The first term on the right side of Equation 5, Δvi,direct, indicates the amount of fluctuation due to the direct wave from the i-th influencing nozzle 102, and its content is the same as Equation 1 and Equation 2 described in embodiment 1. The second term, Δvi,reflect, indicates the amount of fluctuation due to the reflected wave of the pressure wave from the i-th influencing nozzle 102. Its content is the same as Equation 1 and Equation 2 described in embodiment 1, but the total path length L' is used instead of the nozzle-to-nozzle distance L.

[0112] The Σ symbol in the square brackets in the second term on the right side of Equation 5 will now be explained. The subscript k is the number of the wall surface of the polyhedron of the common liquid chamber 140. In this embodiment, the common liquid chamber 140 has been described as a rectangular parallelepiped, but the actual shape may be an even larger polyhedron. Therefore, for a polyhedron with Q wall surfaces, the sum of the reflected waves from the wall surfaces k=1 to Q is calculated.

[0113] Next, we will explain the Σ symbol outside the square brackets in the second term on the right side of Equation 5. The subscript j represents the number of times the pressure wave is reflected from the polyhedral wall surface of the common liquid chamber 140. If reflected waves are not considered, setting M = 0 allows the calculation of the effect of only direct waves. If reflected waves are considered, setting M to the maximum number of reflections considered allows the effect of reflected waves up to M times to be taken into account.

[0114] As explained above, it is possible to calculate the velocity variation Δvi taking into account the "direct wave" and multiple "reflected waves" from the polyhedron. By substituting Δvi obtained from Equation 5 into the right-hand side of Equation 3, it is possible to calculate the velocity variation Δvall, which is the total effect of the "direct wave" from "all affected nozzles" and multiple "reflected waves" from the polyhedron.

[0115] <Embodiment 3> In the third embodiment, the ejection speed v0 of the influencing nozzle 102 and the ejection speed v1 of the nozzle 102 of interest are also taken into consideration when calculating the amount of fluctuation in the ejection speed of the nozzle 102 of interest due to the influence of crosstalk.

[0116] There are other factors besides the influence of crosstalk that cause the ejection characteristics to vary among the nozzles 102. For example, these include dimensional tolerances of the nozzles 102, individual flow paths 130, and supply ports 110, and variations in the electrodynamic characteristics of the energy elements 110. As a result, even in single-nozzle ejection where the influence of crosstalk can be ignored, the ejection characteristics vary among the nozzles 102.

[0117] For example, the nozzle 102 is designed with a design center of the ejection speed Vtyp = 5.0 [m / s]. Even if the same pulse is supplied to each energy element 110 to drive it, ejection speed variations of about σ = 0.3 [m / s], due to manufacturing dimensional tolerances, etc. Assuming that the ejection speed variations follow a normal distribution and considering up to a 3σ interval, variations of about Vtyp = 5.0 ± 1.0 [m / s] can exist.

[0118] Although it is possible to reduce the variation in ejection speed by narrowing manufacturing tolerances, this increases manufacturing costs. On the other hand, high accuracy in droplet placement is required for organic EL display substrates and quantum dot color conversion layers.

[0119] Displacement of ejection speed due to dimensional tolerances and electrodynamic characteristics is generally a static component. In other words, unlike the effects of crosstalk, it is not dependent on the ejection timing of the recording dots, and therefore has the characteristic of being easy to correct. Therefore, in this embodiment, the pre-existing ejection speed variation due to manufacturing tolerances and the like is corrected at the impact position by changing the ejection timing, rather than by speed correction using the energy of the drive pulse.

[0120] Specifically, it is possible to land droplets at ideal positions by correcting the ejection timing according to Equation 4 in Figure 21. The design center (nominal value) of the droplet ejection speed is Vtyp [m / s], the variation in ejection speed due to manufacturing tolerances for each nozzle is Δv [m / s] (signed), and the distance between the ejection head 100 and the substrate 11 is h [m]. From these, the ejection timing offset time ΔToffset [sec] can be calculated.

[0121] In other words, by discharging at a slower timing for nozzles whose discharging speed is faster than the design center due to manufacturing tolerances, etc., and discharging at a faster timing for nozzles whose discharging speed is slower than the design center, it is possible to align the impact position of each nozzle with the target position. In response to a command from the CPU 301, the measurement unit 332 detects the discharging speed of each nozzle 102 of the discharging head 100, and the drive circuit 311 calculates the offset timing. Then, control data in which the discharging timing is changed from the primary control data can be generated.

[0122] Incidentally, when the ejection speed varies statically for each nozzle 102, if it is desired to perform highly accurate calculation of the ejection speed fluctuation due to the influence of crosstalk, the calculation formula may be partially modified.

[0123] Specifically, in this embodiment, a term that depends on the discharge speed of each nozzle is added, as shown in Equation 6. In Equation 2, the amplitude A depends only on the constant C1 and the inter-nozzle distance L, but in Equation 6, two terms are added. Specifically, k0 is a constant for the affected nozzle 102, and Δv0 is the static variation [m / s] in the discharge speed of the affected nozzle 102. k1 is a constant for the target nozzle 102, and Δv1 is the static variation [m / s] in the discharge speed of the target nozzle 102. Note that k0, k1>0.

[0124] A qualitative explanation of Equation 6 is as follows. When considering the case where the fluctuation in the ejection speed of the affected nozzle 102 Δv0 > 0 (i.e., when it is faster than Vtyp), the higher the ejection speed, the greater the influence of crosstalk, and therefore the larger the amplitude A. The converse is also true. When considering the case where the fluctuation in the ejection speed of the target nozzle 102 Δv1 > 0 (i.e., when it is faster than Vtyp), the higher the ejection speed of the target nozzle, the smaller the influence of crosstalk, and therefore the smaller the amplitude A. The converse is also true. Note that if we consider the amplitude A in Equation 6 to be a static velocity fluctuation, Δv0 = Δv1 = 0 [m / s], then it can be seen that this matches the amplitude A in Equation 2.

[0125] As explained above, the ejection velocity fluctuation Δv0 of the affected nozzle 102 and the ejection velocity fluctuation Δv1 of the target nozzle 102 are added to the calculation formula for the velocity fluctuation due to the influence of crosstalk. This makes it possible to more accurately calculate the dynamic fluctuation in the ejection velocity due to the influence of crosstalk, even if there is static fluctuation in the ejection velocity due to manufacturing tolerances, etc.

[0126] <Embodiment 4> 16 is a flowchart of dynamic pulse correction in embodiment 4. First, in S401, drive signal 2, which is the center pulse, is uniformly set as the drive signal for the energy elements 110 of all nozzles 102. In S402, the loop calculation count Rcnt is set to an initial value of Rcnt=0.

[0127] In S403, liquid is actually ejected from each nozzle 102, and the ejection speed for each nozzle 102 is measured using the measurement unit 332, and the measurement results are obtained. During the measurement, the ejection speed is measured by ejecting each nozzle 102 in a single ejection to eliminate the effects of crosstalk. As a result of the measurement, it is assumed that a velocity distribution following a normal distribution of ejection speed Vtyp = 5.0 ± 1.0 [m / s] is obtained due to variations in dimensional tolerances and the like during manufacturing.

[0128] In S404, the ejection timing is corrected for each nozzle 102. The method of correcting the ejection timing is as explained in the third embodiment using Equation 4. However, the ejection timing correction here is performed only for static components (such as manufacturing dimensional tolerances), and no correction is performed for dynamic components (such as speed fluctuation components due to the effects of crosstalk).

[0129] 10 and 13 described in the first embodiment, and therefore will not be described again. In S409, an evaluation value of the variation Δvall after each of the ejection timing correction in S404 and the dynamic pulse correction in S408 is calculated. The evaluation value can be calculated, for example, from statistical data on the number of printed dots and the variation Δvall, and specifically, is the range of the variation Δvall (maximum value-minimum value) or the standard deviation assumed to follow a normal distribution.

[0130] In S410, it is determined whether the evaluation value in S409 is the best of the evaluation values ​​up to that point. If it is the best, in S411, the control data is overwritten as the best data with the contents of the ejection timing correction in S404 and the dynamic pulse correction in S408 calculated this time. Note that when Rcnt=0, there is nothing to compare with, so the result of the first calculation is saved as the best data. If it is determined in S410 that it is not the best, the process proceeds to S412.

[0131] In this way, each time the evaluation value is optimized, the control data resulting from that calculation is saved as the best data. The reason for performing such convergence calculations is as follows: As explained in the third embodiment using equation 6 in FIG. 21, the amplitude A depends on the velocity fluctuation Δv0 of the affected nozzle 102 and the velocity fluctuation Δv1 of the target nozzle 102, and therefore the optimal value cannot necessarily be obtained in a single calculation. By performing loop calculations as in this embodiment, the optimal value can be obtained within at least a limited number of trials.

[0132] If it is determined in S412 that the loop count Rcnt has reached the predetermined maximum value Rmax, then in S413 the ejection timing of all recording dots for one scan is offset uniformly. This is the same processing as S105 in Fig. 10 of embodiment 1. If it is determined in S412 that the loop count Rcnt has not reached the predetermined maximum value Rmax, then the loop count Rcnt is incremented by one, and the process returns to S403, where the same processing is repeated.

[0133] As described above, according to this embodiment, it is possible to obtain the optimum pulse combination from among the pulse combinations for dynamic pulse correction within a preset number of trials.

[0134] <Embodiment 5> In the fifth embodiment, dynamic pulse correction is performed by detecting the difference between the maximum and minimum values ​​of the ejection characteristics due to the influence of crosstalk for each nozzle 102. More specifically, the difference between the maximum and minimum ejection speeds is detected, and dynamic pulse correction is performed. Figure 17 is a flowchart showing the dynamic pulse correction process in this embodiment, and this process can be executed as the process of S104 in Figure 10 and S408 in Figure 16.

[0135] In S508-01, the maximum value Vmax and minimum value Vmin of the variation amount Δvall are calculated for each nozzle 102. As explained in Fig. 13, in the first embodiment, the maximum value Vmax and minimum value Vmin of the variation amount Δvall are calculated for "all nozzles" for one scan, but in this embodiment, the maximum value Vmax and minimum value Vmin of the variation amount Δvall are calculated for each nozzle 102.

[0136] Figure 18(a) is a graph showing the effect of crosstalk on all printed dots for one scan. The horizontal axis represents the amount of fluctuation Δvall [m / s] in the ejection velocity due to the effect of crosstalk, and the vertical axis represents the number of printed dots. Lines C100 and C101 show the distribution of the amount of fluctuation Δvall for the printed dots of nozzle C100 and nozzle C101, respectively. Line 500a represents the distribution regardless of nozzle 102. In other words, adding up the distribution of the amount of fluctuation Δvall for the printed dots of all nozzles 102 results in the distribution represented by line 500a.

[0137] Figure 18(b) shows only lines C100 and C101 from Figure 18(a). The fluctuation amount Δvall of the discharge velocity of nozzle C101 was a maximum value Vmax = -0.05 [m / s] and a minimum value Vmin = -0.34 [m / s]. Similarly, for nozzle C100, Vmax = +0.13 [m / s] and a minimum value Vmin = -0.10 [m / s]. These values ​​are used to identify the velocity fluctuation range for each nozzle 102.

[0138] Returning to FIG. 17, in S508-02, the speed fluctuation range for each nozzle 102 obtained in S508-01 is divided by the division number N to obtain a division width Td' for each nozzle 102. The division number N is the same as the number of types of drive signals for the energy elements 110. When three types of drive signals 1 to 3 are used as in this embodiment, N=3. Td' for nozzle C101 is 1.0 [m / s], and Td' for nozzle C100 is 0.8 [m / s].

[0139] Areas C100-1 to C100-3 in Figure 18(b) each represent the divided areas of nozzle C100. Area C100-1 represents the area for the bottom 1 / 3 of the printed dots, area C100-2 represents the area for the middle 1 / 3 of the printed dots, and area C100-3 represents the area for the above 1 / 3 of the printed dots. Similarly, areas C101-1 to C101-3 each represent the divided areas of nozzle C101. Area C101-1 represents the area for the bottom 1 / 3 of the printed dots, area C101-2 represents the area for the middle 1 / 3 of the printed dots, and area C101-3 represents the area for the above 1 / 3 of the printed dots.

[0140] 17, in S508-03, the allocation of dynamic correction pulses to each recording dot is determined, where the type of drive signal for driving the energy element 110 of the nozzle 102 that forms the recording dot is determined.

[0141] First, for a group of recording dots determined to be in the middle 1 / 3, a pulse corresponding to a standard ejection speed is applied as the drive signal for the energy element 110 (S508-05). Specifically, drive signal 2 in FIG. 7 is applied. For a group of recording dots determined to be in the lower 1 / 3, a pulse that increases the ejection speed beyond the standard amount is applied as the drive signal for the energy element 110. Specifically, drive signal 1 in FIG. 7 is applied. For dots determined to have a speed variation from the upper 1 / 3, a pulse that decreases the speed is applied as the drive signal for the energy element 110. Specifically, drive signal 3 in FIG. 7 is applied.

[0142] It should be noted that the set of drive signals 1 to 3 may be different for each nozzle 102. Figures 19(a) and 19(b) show two sets of drive signals 1 to 3 as examples. The drive signals 1 to 3 in Figure 19(a) are drive signals 1 to 3 for nozzle C100, and are the same as those in Figure 7 of the first embodiment. On the other hand, Figure 19(b) shows drive signals 1 to 3 for nozzle C101, which have a larger amplitude of drive voltage than the drive signals 1 to 3 for nozzle C100 in Figure 19(a).

[0143] Generally, the larger the voltage amplitude of the drive signal, the greater the displacement of the energy element 101, which is a piezoelectric element, and the faster the droplet ejection speed can be. The average value of the ejection speed fluctuation amount Δvall of the C101 nozzle is lower than the ejection speed fluctuation amount Δvall of the C100 nozzle. For this reason, the set of drive signals 1 to 3 in Figure 19(b), which have relatively large voltage amplitudes of the drive signals, is applied.

[0144] Figure 18(c) shows an example of calculating the ejection velocity fluctuation amount Δvall by applying the set of drive signals 1 to 3 in Figure 19(a) as the dynamic correction pulse for nozzle C100, and applying drive signals 1 to 3 in Figure 19(b) as the dynamic correction pulse for nozzle C101. For both nozzle C101 and nozzle C100, the difference between the maximum and minimum values ​​of the fluctuation amount Δvall was within 0.1 [m / s], with the fluctuation amount Δvall = 0 [m / s] as the center.

[0145] The features of this embodiment are summarized below. The spread of the distribution of ejection speed fluctuations due to the effects of crosstalk is generally smaller for the speed distribution of each nozzle than for the distribution of all nozzles. Therefore, the division width Td' is calculated for each nozzle, and drive signals 1 to 3 are applied to each recording dot. Furthermore, a different set of drive voltages 1 to 3 is applied to each nozzle. This makes it easier to control the drive voltage so that the fluctuation amount Δvall = 0 after dynamic pulse correction is at the center. Therefore, it is possible to further suppress the effects of crosstalk.

[0146] <Embodiment 6> In the sixth embodiment, nozzles that are significantly affected by crosstalk are extracted, and their ejection timing is corrected, after which dynamic pulse correction is performed.

[0147] FIG. 20 is a flowchart of dynamic pulse correction in the sixth embodiment, and adds to the processing example of FIG. 16 a process of extracting nozzles that are significantly affected by crosstalk and correcting their ejection timing.

[0148] The processes of S601 to S607 are the same as those of S401 to S407 in Fig. 16. In S608, the nozzle 102 with the largest value of the fluctuation amount Δvall of each nozzle 102 is identified, and the ejection timing of the identified nozzle 102 is corrected.

[0149] When identifying nozzles 102 with a large variation amount Δvall, for example, the nozzles 102 whose absolute value of the variation amount Δvall is in the top 2 to 10% range of all nozzles 102 may be identified. If it is less than 2%, the effect of correcting the ejection timing may be small. On the other hand, if it exceeds 10%, the nozzle 102 whose ejection timing has been corrected may become an affected nozzle 102 and the influence of crosstalk on other nozzles 102 may become strong.

[0150] The ejection timing correction amount tc may be a correction amount that satisfies λ / 4-λ / 8≦tc≦λ / 4+λ / 8, using λ in Equation 2 in Figure 21. Fluctuations in ejection speed due to the effects of crosstalk vary according to the intrinsic wavelength λ, which is determined by the individual liquid chamber 130 and the physical properties of the ink. By shifting the ejection timing of a nozzle 102 with a large amount of fluctuation in ejection speed by about λ / 4, it is possible to significantly reduce the fluctuations in ejection speed.

[0151] In S609 and S610, the fluctuation amounts Δv and Δvall are calculated again. The correction of the ejection timing in S608 reduces the effects of crosstalk from the nozzle 102 for which the absolute value of Δvall was large in S607. Therefore, the calculation results in S609 and S610 should result in a smaller difference between the maximum value Vmax and minimum value Vmin of the fluctuation amount Δvall (speed fluctuation range). In other words, the division width Td obtained by dividing this speed fluctuation range by the division number N becomes smaller, and as a result, the accuracy of dynamic pulse correction can be improved.

[0152] The processes in S611 to S616 are the same as those in S408 to S413 in FIG.

[0153] As described above, in this embodiment, the accuracy of dynamic pulse correction can be improved by correcting the ejection timing for the nozzles 102 with a large fluctuation amount Δvall and performing recalculation. This reduces the number of trials required to obtain more desirable control data.

[0154] <Other embodiments> The dynamic pulse correction described above can also be applied to the pre-drive for controlling meniscus vibration, rather than the main drive for droplet ejection of the energy element 110. The advantages of doing so are as follows: In other words, the main drive for droplet ejection requires not only stable droplet ejection speed, but also stable droplet ejection volume and no satellite or microdroplets. However, changing the main drive using dynamic pulse correction can make it difficult to design a pulse that satisfies all of the above requirements. Therefore, it is meaningful to apply the dynamic pulse correction described above only to the pre-drive for controlling meniscus vibration. This allows for functional separation: correction for the pre-drive is for reducing the effects of crosstalk, while correction for the main drive is for stable droplet ejection.

[0155] Next, in the above embodiment, a piezoelectric element is exemplified as the energy element 110, but dynamic pulse correction can also be applied to an electrothermal conversion element that ejects droplets by fluctuating pressure using a bubbling phenomenon caused by film boiling.

[0156] Next, in the above embodiment, dynamic pulse correction is performed by the electrical circuitry of the liquid ejection device 1, but it may also be performed by an information processing device external to the liquid ejection device 1, such as the host 400. Furthermore, the calculation device may be a parallel calculation device using a GPU, or a logic circuit such as an FPGA or ASIC, other than a CPU.

[0157] Next, in the above embodiment, the focus was on the ejection speed as an ejection characteristic of the nozzle 102 that fluctuates due to the influence of crosstalk, but it is also possible to focus on the ejection amount. Specifically, by appropriately setting the constants in Equations 1 to 6 in Fig. 21, it is possible to reduce the ejection amount fluctuation. Furthermore, since there is generally a proportional relationship between the ejection speed fluctuation and the ejection amount fluctuation due to the influence of crosstalk, if the ejection speed fluctuation can be reduced, the ejection amount fluctuation can also be reduced at the same time.

[0158] The present invention can also be realized by supplying a program that realizes one or more functions of the above-described embodiments to a system or device via a network or a storage medium, and having one or more processors in the computer of the system or device read and execute the program.The present invention can also be realized by a circuit (e.g., ASIC) that realizes one or more functions.

[0159] <Summary of the embodiment> The above-described embodiment discloses the following inventions.

[0160] Item 1. a plurality of nozzles that eject liquid supplied via a common liquid chamber; a plurality of energy elements provided in the plurality of nozzles and generating energy for ejecting liquid from the corresponding nozzles; generating means for generating control data for the plurality of energy elements; A liquid ejection device comprising: The generating means calculating a change in characteristics that is caused in a nozzle corresponding to a second energy element that is driven later by a liquid pressure fluctuation in the common liquid chamber that is caused by driving the first energy element that is the energy element that is driven first when each energy element is driven based on the first control data; generating second control data that adjusts the energy generated by the second energy element based on the calculated change in the characteristics; A liquid ejection device characterized by:

[0161] Item 2. The liquid ejection device according to item 1, the characteristics are ejection characteristics of the nozzles, the generating means calculates a fluctuation amount of the ejection characteristics as the change in the characteristics; A liquid ejection device characterized by:

[0162] Item 3. The liquid ejection device according to item 1, the characteristic is the ejection speed of the liquid ejected from the nozzle, the generating means calculates a fluctuation amount of the ejection velocity as the change in the characteristic; A liquid ejection device characterized by:

[0163] Item 4. The liquid ejection device according to item 2 or 3, The generating means calculating a total amount of fluctuations caused by the plurality of first energy elements as an amount of fluctuation in the characteristic to be caused in the nozzle corresponding to the second energy element; A liquid ejection device characterized by:

[0164] Item 5. The liquid ejection device according to any one of items 1 to 4, the generating means generates the second control data by adjusting the energy generated by the second energy element so as to offset the change in the characteristics. A liquid ejection device characterized by:

[0165] Item 6. The liquid ejection device according to any one of items 2 to 4, The generating means generating the second control data in which the energy generated by the second energy element is adjusted to one of a plurality of types of energy; A liquid ejection device characterized by:

[0166] Item 7. Item 6. The liquid ejection device according to item 6, The generating means a variation range of the variation amount when each energy element is driven based on the first control data, the variation range being equally divided by the number of types of energy to set a plurality of divided ranges; Among the plurality of divided ranges, a divided range to which the fluctuation amount of the nozzle corresponding to the second energy element belongs when each energy element is driven based on the first control data is identified, and the second control data is generated by adjusting the energy generated by the second energy element to a type of energy corresponding to the identified divided range. A liquid ejection device characterized by:

[0167] Item 8. Item 6. The liquid ejection device according to item 6, The generating means a variation range of the variation amount for each nozzle when each energy element is driven based on the first control data is equally divided by the number of types of energy to set a plurality of divided ranges; Among the plurality of divided ranges, a divided range to which the fluctuation amount of the nozzle corresponding to the second energy element belongs when each energy element is driven based on the first control data is identified, and the second control data is generated by adjusting the energy generated by the second energy element to a type of energy corresponding to the identified divided range. A liquid ejection device characterized by:

[0168] Item 9. The liquid ejection device according to any one of items 2 to 4, The generating means In addition to adjusting the generated energy of the second energy element, generating the second control data by uniformly offsetting the drive timings of the plurality of energy elements defined by the first control data based on the amount of fluctuation. A liquid ejection device characterized by:

[0169] Item 10. The liquid ejection device according to any one of items 2 to 4, The generating means Acquire information on the actual measurement of the ejection characteristics of each nozzle, correcting the first control data based on the information before calculating the amount of fluctuation; A liquid ejection device characterized by:

[0170] Item 11. The liquid ejection device according to any one of items 1 to 10, the energy element is a piezoelectric element, The adjustment of the generated energy is an adjustment of a drive signal applied to the piezoelectric element. A liquid ejection device characterized by:

[0171] Item 12. The liquid ejection device according to any one of items 1 to 11, The generating means calculating a change in the characteristic based on first distance information relating to a distance between a nozzle corresponding to the first energy element and a nozzle corresponding to the second energy element; A liquid ejection device characterized by:

[0172] Item 13. Item 13. The liquid ejection device according to item 12, The generating means calculating the change in the characteristic based on, in addition to the first distance information, second distance information relating to each distance between the plurality of nozzles and the solid-liquid interface of the common liquid chamber and the nozzle corresponding to the first energy element and the nozzle corresponding to the second energy element; A liquid ejection device characterized by:

[0173] Item 14. The liquid ejection device according to any one of items 2 to 4, The generating means Identifying some nozzles among the plurality of nozzles in which the fluctuation amount is large; correcting the drive timing of the energy elements corresponding to the identified part of the nozzles, and then recalculating the amount of variation; generating second control data in which the energy generated by the second energy element is adjusted based on the recalculated variation amount; A liquid ejection device characterized by:

[0174] Item 15. The liquid ejection device according to any one of items 2 to 4, The generating means performing a process of replacing the second control data with the first control data and regenerating the second control data a plurality of times; Among the plurality of second control data obtained by performing the process a plurality of times, the best second control data is set as the control data for driving the plurality of energy elements. A liquid ejection device characterized by:

[0175] Item 16. An information processing device that generates control data for driving a plurality of energy elements that are provided in a plurality of nozzles that eject liquid supplied through a common liquid chamber and generate energy for ejecting the liquid from the corresponding nozzles, a generating means for calculating a change in characteristics that will be caused in a nozzle corresponding to a second energy element that is driven later due to a liquid pressure fluctuation in the common liquid chamber caused by driving a first energy element that is driven first when each energy element is driven based on first control data, and for generating second control data that adjusts the energy generated by the second energy element based on the calculated change in characteristics; 1. An information processing device comprising:

[0176] Item 17. A method for generating control data for driving a plurality of energy elements that are provided in a plurality of nozzles that eject liquid supplied through a common liquid chamber and generate energy for ejecting liquid from the corresponding nozzles, the method comprising: a step of calculating a change in characteristics that occurs in a nozzle corresponding to a second energy element that is an energy element that is driven later due to a liquid pressure fluctuation in the common liquid chamber that is caused by driving a first energy element that is an energy element that is driven first when each energy element is driven based on first control data, and generating second control data that adjusts the energy generated by the second energy element based on the calculated change in characteristics; A generating method characterized by:

[0177] Item 18. A storage medium storing a program for causing a computer to execute a generation method for generating drive data for driving a plurality of energy elements that are provided in a plurality of nozzles that eject liquid supplied through a common liquid chamber and generate energy for ejecting liquid from the corresponding nozzles, the method comprising: The method for producing the product comprises: a step of calculating a change in characteristics that occurs in a nozzle corresponding to a second energy element that is an energy element that is driven later due to a liquid pressure fluctuation in the common liquid chamber that is caused by driving a first energy element that is an energy element that is driven first when each energy element is driven based on first control data, and generating second control data that adjusts the energy generated by the second energy element based on the calculated change in characteristics; A storage medium characterized by:

[0178] Item 19. A program for causing a computer to execute a method for generating drive data for driving a plurality of energy elements that are provided in a plurality of nozzles that eject liquid supplied through a common liquid chamber and generate energy for ejecting liquid from the corresponding nozzles, the program comprising: The method for producing the product comprises: a step of calculating a change in characteristics that occurs in a nozzle corresponding to a second energy element that is an energy element that is driven later due to a liquid pressure fluctuation in the common liquid chamber that is caused by driving a first energy element that is an energy element that is driven first when each energy element is driven based on first control data, and generating second control data that adjusts the energy generated by the second energy element based on the calculated change in characteristics; A program characterized by:

[0179] The invention is not limited to the above-described embodiments, and various changes and modifications can be made without departing from the spirit and scope of the invention. Accordingly, the following claims are appended to apprise the public of the scope of the invention. [Explanation of symbols]

[0180] 1 liquid ejection device, 100 ejection head, 102 nozzle, 110 energy element

Claims

1. a plurality of nozzles that eject liquid supplied via a common liquid chamber; a plurality of energy elements provided in the plurality of nozzles and generating energy for ejecting liquid from the corresponding nozzles; generating means for generating control data for the plurality of energy elements; A liquid ejection device comprising: The generating means calculating a change in characteristics that is caused in a nozzle corresponding to a second energy element that is driven later by a liquid pressure fluctuation in the common liquid chamber that is caused by driving the first energy element that is the energy element that is driven first when each energy element is driven based on the first control data; generating second control data that adjusts the energy generated by the second energy element based on the calculated change in the characteristics; A liquid ejection device characterized by:

2. The liquid ejection device according to claim 1 , the characteristics are ejection characteristics of the nozzles, the generating means calculates a fluctuation amount of the ejection characteristics as the change in the characteristics; A liquid ejection device characterized by:

3. The liquid ejection device according to claim 1 , the characteristic is the ejection speed of the liquid ejected from the nozzle, the generating means calculates a fluctuation amount of the ejection velocity as the change in the characteristic; A liquid ejection device characterized by:

4. The liquid ejection device according to claim 2, The generating means calculating a total amount of fluctuations caused by the plurality of first energy elements as an amount of fluctuation in the characteristic to be caused in the nozzle corresponding to the second energy element; A liquid ejection device characterized by:

5. The liquid ejection device according to claim 1 , the generating means generates the second control data by adjusting the energy generated by the second energy element so as to offset the change in the characteristics. A liquid ejection device characterized by:

6. The liquid ejection device according to claim 2, The generating means generating the second control data in which the energy generated by the second energy element is adjusted to one of a plurality of types of energy; A liquid ejection device characterized by:

7. The liquid ejection device according to claim 6, The generating means a variation range of the variation amount when each energy element is driven based on the first control data, the variation range being equally divided by the number of types of energy to set a plurality of divided ranges; Among the plurality of divided ranges, a divided range to which the fluctuation amount of the nozzle corresponding to the second energy element belongs when each energy element is driven based on the first control data is identified, and the second control data is generated by adjusting the energy generated by the second energy element to a type of energy corresponding to the identified divided range. A liquid ejection device characterized by:

8. The liquid ejection device according to claim 6, The generating means a variation range of the variation amount for each nozzle when each energy element is driven based on the first control data is equally divided by the number of types of energy to set a plurality of divided ranges; Among the plurality of divided ranges, a divided range to which the fluctuation amount of the nozzle corresponding to the second energy element belongs when each energy element is driven based on the first control data is identified, and the second control data is generated by adjusting the energy generated by the second energy element to a type of energy corresponding to the identified divided range. A liquid ejection device characterized by:

9. The liquid ejection device according to claim 2, The generating means In addition to adjusting the generated energy of the second energy element, generating the second control data by uniformly offsetting the drive timings of the plurality of energy elements defined by the first control data based on the amount of fluctuation. A liquid ejection device characterized by:

10. The liquid ejection device according to claim 2, The generating means Acquire information on the actual measurement of the ejection characteristics of each nozzle, correcting the first control data based on the information before calculating the amount of fluctuation; A liquid ejection device characterized by:

11. The liquid ejection device according to claim 1 , the energy element is a piezoelectric element, The adjustment of the generated energy is an adjustment of a drive signal applied to the piezoelectric element. A liquid ejection device characterized by:

12. The liquid ejection device according to claim 1 , The generating means calculating a change in the characteristic based on first distance information relating to a distance between a nozzle corresponding to the first energy element and a nozzle corresponding to the second energy element; A liquid ejection device characterized by:

13. The liquid ejection device according to claim 12, The generating means calculating the change in the characteristic based on, in addition to the first distance information, second distance information relating to each distance between the plurality of nozzles and the solid-liquid interface of the common liquid chamber and the nozzle corresponding to the first energy element and the nozzle corresponding to the second energy element; A liquid ejection device characterized by:

14. The liquid ejection device according to claim 2, The generating means Identifying some nozzles among the plurality of nozzles in which the fluctuation amount is large; correcting the drive timing of the energy elements corresponding to the identified part of the nozzles, and then recalculating the amount of variation; generating second control data in which the energy generated by the second energy element is adjusted based on the recalculated variation amount; A liquid ejection device characterized by:

15. The liquid ejection device according to claim 2, The generating means performing a process of replacing the second control data with the first control data and regenerating the second control data a plurality of times; Among the plurality of second control data obtained by performing the process a plurality of times, the best second control data is set as the control data for driving the plurality of energy elements. A liquid ejection device characterized by:

16. An information processing device that generates control data for driving a plurality of energy elements that are provided in a plurality of nozzles that eject liquid supplied through a common liquid chamber and generate energy for ejecting the liquid from the corresponding nozzles, a generating means for calculating a change in characteristics that will be caused in a nozzle corresponding to a second energy element that is driven later due to a liquid pressure fluctuation in the common liquid chamber caused by driving a first energy element that is driven first when each energy element is driven based on first control data, and for generating second control data that adjusts the energy generated by the second energy element based on the calculated change in characteristics; 1. An information processing device comprising:

17. A method for generating control data for driving a plurality of energy elements that are provided in a plurality of nozzles that eject liquid supplied through a common liquid chamber and generate energy for ejecting liquid from the corresponding nozzles, the method comprising: a step of calculating a change in characteristics that occurs in a nozzle corresponding to a second energy element that is an energy element that is driven later due to a liquid pressure fluctuation in the common liquid chamber that is caused by driving a first energy element that is an energy element that is driven first when each energy element is driven based on first control data, and generating second control data that adjusts the energy generated by the second energy element based on the calculated change in characteristics; A generating method characterized by:

18. A storage medium storing a program for causing a computer to execute a generation method for generating drive data for driving a plurality of energy elements that are provided in a plurality of nozzles that eject liquid supplied through a common liquid chamber and generate energy for ejecting liquid from the corresponding nozzles, the method comprising: The method for producing the product comprises: a step of calculating a change in characteristics that occurs in a nozzle corresponding to a second energy element that is an energy element that is driven later due to a liquid pressure fluctuation in the common liquid chamber that is caused by driving a first energy element that is an energy element that is driven first when each energy element is driven based on first control data, and generating second control data that adjusts the energy generated by the second energy element based on the calculated change in characteristics; A storage medium characterized by:

19. A program for causing a computer to execute a method for generating drive data for driving a plurality of energy elements that are provided in a plurality of nozzles that eject liquid supplied through a common liquid chamber and generate energy for ejecting liquid from the corresponding nozzles, the program comprising: The method for producing the product comprises: a step of calculating a change in characteristics that occurs in a nozzle corresponding to a second energy element that is an energy element that is driven later due to a liquid pressure fluctuation in the common liquid chamber that is caused by driving a first energy element that is an energy element that is driven first when each energy element is driven based on first control data, and generating second control data that adjusts the energy generated by the second energy element based on the calculated change in characteristics; A program characterized by:

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