Inkjet printing method and inkjet printing apparatus

Abstract

An inkjet printing method and an inkjet printing apparatus are provided. The inkjet printing method includes: generating an initial sequence in which a plurality of initial numbers are arranged in a matrix form; generating a correction sequence by correcting the plurality of initial numbers with a plurality of correction numbers on the basis of a variable range of the amount of liquid droplets ejected into the plurality of pixel regions and a measurement error range of the discharge amount of a plurality of nozzles that discharge the liquid droplets into the plurality of pixel regions; and discharging the droplets to the plurality of pixel regions while adjusting the discharge amount of each nozzle based on the correction sequence.

Description

Technical Field

[0001] The present disclosure relates to an inkjet printing method and more particularly to an inkjet printing method and an inkjet printing apparatus for performing the inkjet printing method. Background Art

[0002] A display device is a device that displays an image to provide visual information to a user. A display device can be manufactured using an inkjet printing method. The inkjet printing method can be performed using an inkjet printing device that forms an opening (e.g., a pixel area) on a substrate and ejects ink into the opening. Summary of the invention

[0003] Embodiments provide an inkjet printing method with improved reliability.

[0004] An embodiment provides an inkjet printing apparatus that performs an inkjet printing method.

[0005] The technical objectives to be achieved by the present disclosure are not limited to those described herein, and those skilled in the art will clearly understand other technical objectives not mentioned herein from the description of the present disclosure.

[0006] According to an embodiment, an inkjet printing method includes: generating an initial sequence in which a plurality of initial numbers are arranged in a matrix form; generating a correction sequence by correcting a plurality of initial numbers with a plurality of correction numbers based on a variable range of the amount of droplets ejected into a plurality of pixel areas and a measurement error range of the discharge amount of a plurality of nozzles that discharge droplets into the plurality of pixel areas; and discharging droplets into the plurality of pixel areas while adjusting the discharge amount of each nozzle based on the correction sequence.

[0007] In an embodiment, the variable range may be about -A% to about +A%, the measurement error range may be about -B% to about +B%, each of A and B is a positive number, and B is less than A, and when generating a correction sequence, the maximum value among the plurality of initial numbers may be corrected to a number calculated by the following Formula 1,

[0008] [Formula 1]

[0009] AB.

[0010] In an embodiment, when generating a correction sequence, the minimum value among the plurality of initial numbers may be corrected to a number calculated by the following formula 2,

[0011] [Formula 2]

[0012] -(AB).

[0013] In an embodiment, for a plurality of remaining numbers other than the maximum value and the minimum value among the plurality of initial numbers, when C is a ratio of any remaining number to a difference between the maximum value and the minimum value, when generating a correction sequence, the remaining number may be corrected to a number calculated by the following formula 3,

[0014] [Formula 3]

[0015] (AB)x(2C-1).

[0016] In an embodiment, the variable range may be about -A% to about +A%, the measurement error range may be about -B% to about +B%, each of A and B may be a positive number, and B may be less than 1, and when generating a correction sequence, the maximum value among the plurality of initial numbers may be corrected to A, and the minimum value among the plurality of initial numbers may be corrected to -A, and for a plurality of remaining numbers other than the maximum value and the minimum value among the plurality of initial numbers, in the case where C is a ratio of any remaining number to a difference between the maximum value and the minimum value, when generating a correction sequence, the remaining number may be corrected to a number calculated by the following Formula 4,

[0017] [Formula 4]

[0018] A x(2C-1).

[0019] In an embodiment, when the droplet is discharged to a plurality of pixel regions, a plurality of correction numbers may correspond to the plurality of pixel regions.

[0020] In an embodiment, when liquid droplets are discharged to a plurality of pixel regions, a discharge amount of a nozzle corresponding to a pixel region among the plurality of pixel regions may be adjusted based on a correction number corresponding to a pixel region among the plurality of pixel regions.

[0021] In an embodiment, the discharge amount of the nozzle corresponding to the pixel area may be increased or decreased by a percentage of the absolute value of the correction number.

[0022] In an embodiment, when the correction number is a positive number, the discharge amount of the nozzle corresponding to the pixel area may be increased by a percentage of the absolute value of the correction number.

[0023] In an embodiment, in the case where the correction number is a negative number, the discharge amount of the nozzle corresponding to the pixel area may be reduced by a percentage of the absolute value of the correction number.

[0024] In an embodiment, each of the plurality of initial numbers may be an integer greater than or equal to approximately 0.

[0025] In an embodiment, each of the plurality of initial numbers may have a spatial frequency in the initial sequence, and a difference in the spatial frequency between the plurality of initial numbers may be about 10% or less.

[0026] In an embodiment, a plurality of initial numbers may have the same spatial frequency in the initial sequence.

[0027] In an embodiment, when discharging droplets to a plurality of pixel regions, a driving waveform signal applied to a plurality of nozzles may be changed to adjust the discharge amount of the plurality of nozzles.

[0028] In an embodiment, the driving waveform signal may have a driving interval and a non-driving interval before and after the driving interval, and when the droplets are discharged to the plurality of pixel regions, the magnitude of the voltage of the driving interval may be changed.

[0029] In an embodiment, the driving waveform signal may have a driving interval and a non-driving interval before and after the driving interval, and when the droplets are discharged to a plurality of pixel regions, the length of the driving interval may be changed.

[0030] In an embodiment, the driving waveform signal may have a driving interval and a non-driving interval before and after the driving interval, and when the droplets are discharged to a plurality of pixel regions, the frequency of the driving interval included in the driving waveform signal may be changed.

[0031] In an embodiment, a plurality of nozzles may form a nozzle row, and when discharging droplets to a plurality of pixel regions, a discharge amount of each of the plurality of nozzles may be individually adjusted.

[0032] According to an embodiment, an inkjet printing device includes: a plurality of nozzles that discharge droplets to a plurality of pixel areas, an input portion into which a measurement error range of the discharge amounts of the plurality of nozzles is input, a calculation portion that generates a correction sequence in which a plurality of correction numbers are arranged in a matrix form based on data input to the input portion, a waveform generation portion that generates a drive waveform signal applied to the plurality of nozzles, and an output portion that outputs a control signal to the waveform generation portion based on the correction sequence.

[0033] In an embodiment, the input unit may further input a variable range of the amount of the liquid droplets discharged to the plurality of pixel regions.

[0034] In an embodiment, the input unit may further input an initial sequence in which a plurality of initial numbers corresponding to a plurality of pixel regions are arranged in a matrix form.

[0035] In an embodiment, the calculation part may correct the plurality of initial numbers with the plurality of correction numbers based on the variable range and the measurement error range.

[0036] In an embodiment, the variable range may be about -A% to about +A%, the measurement error range may be about -B% to about +B%, each of A and B may be a positive number, and B may be less than A, and the plurality of correction numbers may include a number calculated by the following Formula 1 and a number calculated by the following Formula 2,

[0037] [Formula 1]

[0038] AB

[0039] [Formula 2]

[0040] -(AB).

[0041] In an embodiment, for a plurality of remaining numbers other than the maximum value and the minimum value among the plurality of initial numbers, in the case where C is a ratio of any remaining number to a difference between the maximum value and the minimum value, the plurality of correction numbers may further include a number calculated by the following Formula 3,

[0042] [Formula 3]

[0043] (AB)x(2C-1).

[0044] In an embodiment, the variable range may be about -A% to about +A%, the measurement error range may be about -B% to about +B%, each of A and B may be a positive number, and B may be less than 1, and for a plurality of remaining numbers excluding a maximum value and a minimum value among a plurality of initial numbers, in the case where C is a ratio of any one of the remaining numbers to a difference between the maximum value and the minimum value, the plurality of correction numbers may include A, -A, and a number calculated by the following Formula 4,

[0045] [Formula 4]

[0046] A x(2C-1).

[0047] In an embodiment, the driving waveform signal may have a driving interval and a non-driving interval before and after the driving interval, and the control signal may include at least one of a first control signal that controls the amplitude of a voltage of the driving interval, a second control signal that controls the length of the driving interval, and a third control signal that controls the frequency of the driving interval included in the driving waveform signal.

[0048] According to an embodiment, an inkjet printing method may include: generating an initial sequence in which a plurality of initial numbers are arranged in a matrix form; generating a correction sequence by correcting a plurality of initial numbers with a plurality of correction numbers based on a variable range of the amount of droplets ejected into a plurality of pixel areas and a measurement error range of a discharge amount of a plurality of nozzles that discharge droplets into the plurality of pixel areas; and discharging droplets into the plurality of pixel areas while adjusting the discharge amount of each nozzle based on the correction sequence.

[0049] Accordingly, the discharge amounts of the plurality of nozzles can be adjusted in advance by taking into account a measurement error that may occur when the discharge amounts of the plurality of nozzles are measured by a measuring device or the like. Accordingly, the difference in discharge amount of each nozzle that has not been identified due to a measurement error in the discharge amount of the nozzle can be easily corrected.

[0050] Accordingly, the discharge amount of the droplets finally discharged to each of the plurality of pixel regions by the inkjet printing method according to the embodiment can be relatively uniform. That is, a phenomenon in which there is a relative difference in the discharge amount of the droplets discharged to the pixel region in a specific column among the plurality of pixel regions can be prevented. Accordingly, stains such as mura can be prevented from occurring in a portion corresponding to the pixel region of the specific column. Accordingly, the reliability of the inkjet printing process can be improved.

[0051] It is to be understood that both the foregoing general description and the following detailed description are explanatory and are intended to provide further explanation of the disclosure as claimed. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Illustrative, non-limiting embodiments will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings.

[0053] Figure 1 is a schematic perspective view showing an inkjet printing apparatus according to an embodiment.

[0054] Figure 2 It is shown that the Figure 1 Schematic diagram of the head of the inkjet printing device.

[0055] Figure 3 It is shown that the Figure 1 Schematic diagram of a controller in an inkjet printing device.

[0056] Figure 4 It shows the input to Figure 3 Schematic diagram of an example of an initial sequence of input parts.

[0057] Figure 5 It is shown by Figure 3 A schematic diagram of an example of a correction sequence generated by a calculation unit.

[0058] Figure 6 It is shown by Figure 3 Schematic diagram of an example of a driving waveform signal generated by a waveform generating unit.

[0059] Figure 7 It is shown that Figure 3 A schematic diagram of an example of a control portion applying a driving waveform signal to adjust the discharge amount of droplets discharged to a plurality of pixel regions.

[0060] Figure 8 It shows that according to Figure 7 A schematic diagram of the amount of droplets discharged to a plurality of pixel regions before the discharge amount.

[0061] Fig. 9 It shows that according to Figure 7Schematic diagram of the amount of droplets discharged to a plurality of pixel regions after the discharge amount.

[0062] Fig.10 It is shown that the use Figure 1 Schematic flow chart of an inkjet printing method of an inkjet printing device. DETAILED DESCRIPTION

[0063] Hereinafter, embodiments of the present disclosure will be described in more detail with reference to the accompanying drawings. In the accompanying drawings, the same reference numerals and / or characters will be used for the same components, and repeated description of the same components may be omitted.

[0064] As used herein, the terms "about" or "approximately" are inclusive of the stated value and mean within an acceptable range of deviation for the particular value as determined by one of ordinary skill in the art, taking into account the errors associated with the measurements and with the measurement of a particular quantity (i.e., the limitations of the measurement system). For example, "about" may mean within one or more standard deviations, or within ±30%, 20%, 10%, 5% of the stated value.

[0065] The term "and / or" includes all combinations of one or more that the associated configurations can define. For example, "A and / or B" can be understood to mean "A, B, or A and B".

[0066] For the purpose of this disclosure, the phrase "at least one of A and B" may be interpreted as only A, only B, or a combination of A and B. Moreover, "at least one of X, Y, and Z" and "at least one selected from the group consisting of X, Y, and Z" may be interpreted as only X, only Y, only Z, or any combination of two or more of X, Y, and Z.

[0067] Unless otherwise defined or implied herein, all terms (including technical and scientific terms) used herein have the same meaning as those commonly understood by those skilled in the art to which the present disclosure belongs. It will also be understood that, unless explicitly defined as such herein, terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology and the present disclosure, and should not be interpreted in an ideal or overly formal sense.

[0068] Figure 1 is a schematic perspective view showing an inkjet printing apparatus according to an embodiment.

[0069] Reference Figure 1 The inkjet printing apparatus 10 may include a head HD and a controller CON. The inkjet printing apparatus 10 may be positioned on a stage ST.

[0070] The stage ST may be parallel to a plane defined by the first direction DR1 and the second direction DR2 intersecting the first direction DR1. For example, the first direction DR1 and the second direction DR2 may be perpendicular to each other.

[0071] The stage ST may support a target substrate SUB. Droplets IK may be deposited on the target substrate SUB to form a pattern.

[0072] The head HD may be spaced apart from the stage ST in a third direction DR3 intersecting each of the first direction DR1 and the second direction DR2. For example, the third direction DR3 may be perpendicular to each of the first direction DR1 and the second direction DR2.

[0073] The head HD may discharge the droplets IK to the target substrate SUB disposed on the stage ST. The head HD may include one or more nozzles NZ that discharge the droplets IK to the target substrate SUB in a direction opposite to the third direction DR3. For example, a plurality of nozzles NZ may be arranged in the first direction DR1.

[0074] The head HD may move in the second direction DR2. The head HD may move in the second direction DR2 and / or discharge the droplets IK to the target substrate SUB. For example, the head HD may discharge the droplets IK in a stationary state, then move a distance (e.g., a predetermined or selectable distance) in the second direction DR2 and discharge the droplets IK again in a stationary state. However, the present disclosure is not limited thereto, and the head HD may move and repeatedly discharge the droplets IK. The stage ST may move in the second direction DR2 and / or the head HD may discharge the droplets IK in a stationary state.

[0075] A plurality of pixel regions PXA may be defined on the target substrate SUB. For example, the plurality of pixel regions PXA may be arranged in a matrix in the first direction DR1 and the second direction DR2. The plurality of pixel regions PXA may be spaces for accommodating droplets IK discharged from the head HD. For example, the head HD may move in the second direction DR2 and discharge the droplets IK to the plurality of pixel regions PXA.

[0076] The droplets IK discharged to the target substrate SUB may be hardened to form a pattern. For example, the pattern may be formed in the plurality of pixel areas PXA. For example, the droplets IK discharged from the head HD may form a pattern in the first direction DR1 and the second direction DR2.

[0077] The controller CON may control driving of the head HD. The controller CON may apply (or output) a driving waveform signal DS to the head HD. The driving waveform signal DS may include information on ejection of the droplet IK. The head HD may be driven in response to the driving waveform signal DS.

[0078] Figure 2 It is shown that the Figure 1 Schematic diagram of the head of the inkjet printing device.

[0079] Reference Figure 1 and Figure 2 , the head HD may include a plurality of nozzles NZ. For example, the head HD may include a first nozzle NZ1, a second nozzle NZ2, a third nozzle NZ3, ..., an i-2nd nozzle NZi-2, an i-1st nozzle NZi-1, and an i-th nozzle NZi (where i is a natural number greater than 0). Each of the first nozzle NZ1 to the i-th nozzle NZi may discharge a droplet IK.

[0080] In an embodiment, the discharge amount of the droplet IK discharged from each of the first nozzle NZ1 to the i-th nozzle NZi may be adjusted individually. For example, the controller CON may adjust the discharge amount of the droplet IK for each of the first nozzle NZ1 to the i-th nozzle NZi individually. Hereinafter, for the convenience of explanation, the discharge amount of the droplet IK is referred to as the discharge amount.

[0081] Figure 3 It is shown that the Figure 1 Schematic diagram of a controller in an inkjet printing device.

[0082] Reference Figure 1 and Figure 3 , the controller CON may include an input part IP, a calculation part CP, a waveform generation part WS and / or an output part OP.

[0083] Various data related to the inkjet printing process using the inkjet printing apparatus 10 may be input to the input part IP.

[0084] The variable range VR of the amount of the droplets IK discharged to the plurality of pixel regions PXA may be input to the input portion IP. The variable range VR may mean an allowable range of the difference between the amount of the droplets IK actually discharged to each of the plurality of pixel regions PXA and the target amount of the droplets IK to be discharged. For example, the variable range VR may be about -A% to about +A%. Here, A may be a positive number.

[0085] Information on the discharge amount of multiple nozzles NZ measured by a measuring device or the like may be input to the input portion IP. A measurement error range MER that may occur when the discharge amount of multiple nozzles NZ is measured by a measuring device or the like may be input to the input portion IP. The measurement error range MER may mean an allowable range of measurement errors that may occur due to various factors (temperature, pressure, discharge surface characteristics, etc.) when the discharge amount of each of the multiple nozzles NZ is measured by a measuring device or the like. For example, the measurement error range MER may be about -B% to about +B%. Here, B may be a positive number. In an embodiment, B may be less than A.

[0086] An initial sequence ISQ in which a plurality of initial numbers corresponding to a plurality of pixel areas PXA are arranged in a matrix form may be input to the input part IP. Each of the plurality of initial numbers may be an integer greater than or equal to about 0.

[0087] The initial sequence ISQ may be a sequence generated in consideration of a spatial frequency. Specifically, each of the plurality of initial numbers may have a spatial frequency in the initial sequence ISQ, and a difference in the spatial frequency between the plurality of initial numbers may be about 10% or less.

[0088] For example, the initial sequence ISQ may be a sequence in which a plurality of initial numbers are arranged at a relatively uniform spatial frequency to prevent local variations in the spatial frequency.

[0089] Specifically, in the initial sequence ISQ, for each absolute value, the number of initial numbers having the same absolute value among the plurality of initial numbers may be the same or similar. For example, in the initial sequence ISQ, in the case where an initial number having a first absolute value and an initial number having a second absolute value are randomly selected, the difference between the number of initial numbers having the first absolute value and the number of initial numbers having the second absolute value may be about 10% or less. For example, in the case where the number of initial numbers having the first absolute value is about 20, the number of initial numbers having the second absolute value may be about 18 to about 22. However, the present disclosure is not necessarily limited thereto, and in the initial sequence ISQ, the distribution of the initial numbers may be changed in various ways.

[0090] In an embodiment, various algorithms may be used to generate the initial sequence ISQ. An error distribution method may be used as an algorithm for generating the initial sequence ISQ. For example, an FM mask method may be used as an algorithm for generating the initial sequence ISQ. Specifically, the VOID AND CLUSTER rule in the FM mask method may be used. For example, the initial sequence ISQ may be generated by executing the VOID AND CLUSTER rule multiple times. However, the present disclosure is not limited thereto, and the initial sequence ISQ may be generated in various ways.

[0091] Figure 4 It shows the input to Figure 3 Schematic diagram of an example of an initial sequence of input parts.

[0092] exist Figure 4 In FIG. 1 , an initial sequence ISQ in which a total of 64 initial numbers are arranged in a matrix form having 8 rows IR1, IR2, IR3, IR4, IR5, IR6, IR7 and IR8 and 8 columns IC1, IC2, IC3, IC4, IC5, IC6, IC7 and IC8 is shown as an example. Figure 4, the minimum value among the plurality of initial numbers is 0, and the maximum value among the plurality of initial numbers is 15. However, the present disclosure is not necessarily limited thereto, and the number of initial numbers, the number of rows, and the number of columns of the initial sequence ISQ may vary according to the implementation. The minimum value and the maximum value (i.e., the combination of the initial numbers) may vary according to the implementation.

[0093] Refer again Figure 1 and Figure 3 , the calculation part CP may generate a correction sequence CSQ based on the data input to the input part IP. For example, the calculation part CP may generate a correction sequence CSQ based on the variable range VR, the measurement error range MER and the initial sequence ISQ input to the input part IP. The correction sequence CSQ may be a sequence in which a plurality of correction numbers are arranged in a matrix form. The correction number may be a number obtained by correcting the initial number based on the variable range VR, the measurement error range MER and / or the initial sequence ISQ.

[0094] The calculation method by which the calculation unit CP generates the correction sequence CSQ from the initial sequence ISQ may be as follows.

[0095] As described above, the variable range VR of the input to the input part IP may be -A% to +A%, and the measurement error range MER of the input to the input part IP may be -B% to +B%.

[0096] In this case, the calculation part CP may correct the maximum value among the plurality of initial numbers in the initial sequence ISQ to the number calculated by Formula 1.

[0097] [Formula 1]

[0098] AB

[0099] The calculation part CP may correct the minimum value among the plurality of initial numbers in the initial sequence ISQ to the number calculated by Formula 2.

[0100] [Formula 2]

[0101] -(AB)

[0102] For the remaining numbers other than the maximum value and the minimum value among the multiple initial numbers, the calculation part CP can correct each of the multiple remaining numbers to a number at a point between approximately -(AB) and approximately +(AB) corresponding to each point in the multiple remaining numbers between the maximum value and the minimum value.

[0103] For example, in the case where the ratio of any one of the remaining numbers to the difference between the maximum value and the minimum value is about C, the calculation part CP may correct the remaining number to the number calculated by Formula 3.

[0104] [Formula 3]

[0105] (AB)x(2C-1)

[0106] As a result, when the variable range VR input to the input part IP is approximately -A% to approximately +A%, the measurement error range MER input to the input part IP is approximately -B% to approximately +B%, and C is the ratio of the difference between the maximum value and the minimum value of any residual number to the multiple initial numbers, the multiple correction numbers of the correction sequence CSQ generated by the calculation part CP may include the number calculated by Formula 1, the number calculated by Formula 2, and the number calculated by Formula 3.

[0107] Figure 5 It is shown by Figure 3 A schematic diagram of an example of a correction sequence generated by a calculation unit.

[0108] Reference Figure 4 and Figure 5 , the principle of generating the correction sequence CSQ by the calculation part CP will be described as an example.

[0109] For example, in the case where the variable range VR is about -3% to about +3% and the measurement error range is about -1% to about +1%, Figure 5 The correction sequence CSQ can be obtained by the calculation part CP (refer to Figure 3 )based on Figure 4 The initial sequence ISQ generates the sequence. For example, Figure 5 In the figure, a correction sequence CSQ in which a total of 64 correction numbers are arranged in a matrix form with 8 rows CR1, CR2, CR3, CR4, CR5, CR6, CR7 and CR8 and 8 columns CC1, CC2, CC3, CC4, CC5, CC6, CC7 and CC8 is shown as an example.

[0110] In this case, the calculation part CP may correct the maximum value 15 among the multiple initial numbers to the correction number 2 (for example, 3-1) according to Formula 1. The calculation part CP may correct the minimum value 0 among the multiple initial numbers to the correction number -2 (for example, -(3-1)) according to Formula 2. The calculation part CP may correct the remaining numbers (for example, the initial numbers from 1 to 14) other than the maximum value 15 and the minimum value 0 according to Formula 3. In order to explain the method of correcting the remaining number 10 as an example, the ratio of the remaining number 10 to 15 as the difference between the maximum value and the minimum value is 10 / 15, so 10 / 15 is substituted into C in Formula 3, and the remaining number 10 can be corrected to a correction number of about 0.67. In order to explain the method of correcting the remaining number 3 as an example, the ratio of the remaining number 3 to 15 as the difference between the maximum value and the minimum value is 3 / 15, so 3 / 15 is substituted into C in Formula 3, and the remaining number 3 can be corrected to a correction number of about -1.2.

[0111] As a result, the calculation unit CP is based on Figure 4The correction sequence CSQ generated by the initial sequence ISQ may be a sequence in which a plurality of correction numbers from -2 to 2 are arranged in a matrix form.

[0112] In an embodiment, when the measurement error range MER is a negligible small range (for example, when B is less than 1), the calculation part CP can correct the maximum value among the multiple initial numbers in the initial sequence ISQ to A, correct the minimum value among the multiple initial numbers in the initial sequence ISQ to -A, and can correct the remaining numbers among the multiple initial numbers to the numbers calculated by Formula 4.

[0113] [Formula 4]

[0114] A x(2C-1)

[0115] For example, in the case where the measurement error range MER is a negligibly small range, the calculation part CP may generate the correction sequence CSQ by considering only the variable range VR without considering the measurement error range MER.

[0116] Refer again Figure 1 and Figure 3 , the waveform generating section WS may generate a driving waveform signal DS applied to the head HD (eg, the plurality of nozzles NZ).

[0117] In an embodiment, the driving waveform signal DS may include one or more driving waveform signals respectively applied to the plurality of nozzles NZ. For example, the waveform generating part WS may generate the first to i-th driving waveform signals that control whether to discharge droplets and the discharge amount of each of the first to i-th nozzles NZ1 to NZi. The first to i-th driving waveform signals may correspond one to one to the first to i-th nozzles NZ1 to NZi.

[0118] Figure 6 It is shown by Figure 3 Schematic diagram of an example of a driving waveform signal generated by a waveform generating unit.

[0119] exist Figure 6 , for convenience of explanation, only the first driving waveform signal DS1 among the first to i-th driving waveform signals is selectively shown. The second to i-th driving waveform signals may have a form substantially similar to the first driving waveform signal DS1.

[0120] Further references Figure 6, the first driving waveform signal DS1 may have a driving interval P1 and a non-driving interval P2 before and after the driving interval P1. The driving interval P1 may include a rising interval, a holding interval, and a falling interval. The driving interval P1 may be an interval in which the first nozzle NZ1 having received the first driving waveform signal DS1 is driven to discharge the droplet IK. The non-driving interval P2 may be an interval in which the first nozzle NZ1 is not driven.

[0121] By changing the amplitude of the voltage of the driving interval P1, the length of the driving interval P1 and / or the non-driving interval P2, the frequency of the driving interval P1 included in one driving waveform signal, or the like, it is possible to adjust whether the nozzle receiving the driving waveform signal discharges droplets, the discharge amount, or the like. For example, in order to control whether each of the first nozzle NZ1 to the i-th nozzle NZi discharges droplets and the discharge amount, the amplitude of the voltage of the driving interval of each of the first driving waveform signal to the i-th driving waveform signal, the length of the driving interval, the frequency of the driving interval, or the like can be changed.

[0122] For example, by changing the amplitude of the voltage of the driving interval of the first driving waveform signal DS1, the length of the driving interval, the frequency of the driving interval, or the like, it is possible to adjust whether the first nozzle NZ1 discharges droplets, the discharge amount, or the like. Similarly, by changing the amplitude of the voltage of the driving interval of the second driving waveform signal, the length of the driving interval, the frequency of the driving interval, or the like, it is possible to adjust whether the second nozzle NZ2 discharges droplets, the discharge amount, or the like. By the same principle, it is possible to adjust whether each of the third nozzle NZ3 to the i-th nozzle NZi discharges droplets and the discharge amount of droplets.

[0123] The output part OP may change the driving waveform signal DS. For example, the output part OP may output a control signal CS that changes the driving waveform signal DS. The output part OP may apply the control signal CS to the waveform generating part WS.

[0124] In the case where it is necessary to adjust whether each of the first nozzle NZ1 to the i-th nozzle NZi discharges droplets or the discharge amount, the control signal CS output from the output part OP can be transmitted to the waveform generating part WS. Accordingly, the driving waveform signal DS (for example, at least one of the first driving waveform signal to the i-th driving waveform signal) can be changed. For example, the control signal CS can change the amplitude of the voltage of at least one driving interval among the first driving waveform signal to the i-th driving waveform signal, the length of the driving interval, the frequency of the driving interval, or the like.

[0125] Specifically, the output part OP may receive the correction sequence CSQ from the calculation part CP and output the control signal CS based on the correction sequence CSQ.

[0126] The output unit OP may correspond the plurality of correction numbers in the correction sequence CSQ to the plurality of pixel regions PXA. If the number of rows and columns of the correction sequence CSQ is less than the number of rows and columns of the matrix of the plurality of pixel regions PXA, the plurality of correction numbers may be corresponded to the plurality of pixel regions PXA by repeatedly arranging the correction sequence CSQ.

[0127] The correction number corresponding to a pixel area among the plurality of pixel areas PXA can be identified as the degree to which the discharge amount of the nozzle corresponding to the pixel area needs to be adjusted. In other words, the discharge amount of the nozzle corresponding to the pixel area can be adjusted based on the corresponding correction number.

[0128] For example, when the correction number corresponding to the pixel area is a positive number, the output part OP may output the control signal CS to increase the discharge amount of the nozzle corresponding to the pixel area by a percentage of the absolute value of the correction number.

[0129] For example, when the correction number corresponding to the pixel area is a positive number, in response to the control signal CS output by the output unit OP, the waveform generating unit WS may generate a driving waveform signal that is changed so that the discharge amount of the nozzle increases as a percentage of the absolute value of the correction number, and apply the changed driving waveform signal to the nozzle.

[0130] For example, in a case where the correction number corresponding to the pixel area is a negative number, the output part OP may output the control signal CS to reduce the discharge amount of the nozzle corresponding to the pixel area by a percentage of the absolute value of the correction number.

[0131] For example, in a case where the correction number corresponding to the pixel area is a negative number, in response to the control signal CS output by the output unit OP, the waveform generating unit WS may generate a driving waveform signal that is changed so that the discharge amount of the nozzle is reduced by a percentage of the absolute value of the correction number, and apply the changed driving waveform signal to the nozzle.

[0132] In an embodiment, the control signal CS may include a first control signal CS1 that controls the amplitude of the voltage of the driving interval P1. For example, the first control signal CS1 may increase the amplitude of the voltage of the driving interval of the driving waveform signal applied to the nozzle that needs to increase the discharge amount. The first control signal CS1 may reduce the amplitude of the voltage of the driving interval of the driving waveform signal applied to the nozzle that needs to reduce the discharge amount. However, the present disclosure is not necessarily limited to this.

[0133] In an embodiment, the control signal CS may include a second control signal CS2 that controls the length of the driving interval P1. For example, the second control signal CS2 may extend the length of the driving interval of the driving waveform signal applied to the nozzle that needs to increase the discharge amount. The second control signal CS2 may shorten the length of the driving interval of the driving waveform signal applied to the nozzle that needs to reduce the discharge amount. However, the present disclosure is not necessarily limited to this.

[0134] In an embodiment, the control signal CS may include a third control signal CS3 that controls the frequency of the driving interval P1. For example, the third control signal CS3 may increase the frequency of the driving interval of the driving waveform signal applied to the nozzle that needs to increase the discharge amount. The third control signal CS3 may reduce the frequency of the driving interval of the driving waveform signal applied to the nozzle that needs to reduce the discharge amount. However, the present disclosure is not necessarily limited to this.

[0135] Figure 7 It is shown that Figure 3 A schematic diagram of an example of a control portion applying a driving waveform signal to adjust the discharge amount of droplets discharged to a plurality of pixel regions.

[0136] For example, Figure 7 is shown in which the output section OP responds to the Figure 5 Schematic diagram of an example of adjusting the discharge amounts of a plurality of nozzles NZ corresponding to a plurality of pixel areas PXA by using a control signal CS output by a correction sequence CSQ and a drive waveform signal DS applied by a waveform generating section WS.

[0137] Further references Figure 7 , the principle of controlling the discharge amount of the droplet IK by the controller CON will be explained as an example.

[0138] For the convenience of explanation, Figure 7 , an example is shown in which the plurality of pixel areas PXA have 8 rows PR1, PR2, PR3, PR4, PR5, PR6, PR7 and PR8 and 8 columns PC1, PC2, PC3, PC4, PC5, PC6, PC7 and PC8, and the 8 rows PR1, PR2, ..., PR8 of the plurality of pixel areas PXA correspond to Figure 5 The eight rows CR1, CR2, ..., CR8 of the correction sequence CSQ, and the eight columns PC1, PC2, ..., PC8 of the plurality of pixel areas PXA correspond to Figure 5 8 columns CC1, CC2, ..., CC8 of the correction sequence CSQ. However, as described above, the present disclosure is not necessarily limited thereto, and the number of rows and columns of the correction sequence CSQ may be less than the number of rows and columns of the plurality of pixel regions PXA. In this case, by repeatedly arranging the correction sequence CSQ, a plurality of correction numbers may correspond to the plurality of pixel regions PXA.

[0139] Figure 7A front discharge amount BV indicating the discharge amount of a plurality of nozzles corresponding to a plurality of pixel areas PXA before adjustment based on the correction sequence CSQ, and a rear discharge amount AV indicating the discharge amount of a plurality of nozzles corresponding to a plurality of pixel areas PXA after adjustment based on the correction sequence CSQ are shown. The unit of each of the front discharge amount BV and the rear discharge amount AV is picoliter (pL).

[0140] For example, in the front discharge volume BV, the discharge volume of the nozzles corresponding to the pixel area located in the seventh column PC7 among the plurality of pixel areas PXA may be about 4.95pL before adjustment based on the correction sequence CSQ, and the discharge volume of the nozzles corresponding to the remaining pixel areas may be about 5pL.

[0141] Taking the discharge amount of the nozzle corresponding to the pixel area located in the first row PR1 and the first column PC1 among the plurality of pixel areas PXA as an example, the front discharge amount (about 5 pL) can be reduced by a percentage (for example, about 2%) of the absolute value of the correction number -2 (the correction number in the first row CR1 and the first column CC1 of the correction sequence CSQ) and adjusted to about 4.9 pL. For example, in the rear discharge amount AV, the discharge amount corresponding to the pixel area in the first row PR1 and the first column PC1 among the plurality of pixel areas PXA can be 4.9 pL.

[0142] Taking the discharge amount of the nozzle corresponding to the pixel area located in the fifth row PR5 and the seventh column PC7 among the plurality of pixel areas PXA as an example, the front discharge amount (about 4.95 pL) can be increased by a percentage (for example, about 2%) of the absolute value of the correction number 2 (the correction number in the fifth row CR5 and the seventh column CC7 of the correction sequence CSQ) and adjusted to about 5.049 pL. For example, in the rear discharge amount AV, the discharge amount corresponding to the pixel area in the fifth row PR5 and the seventh column PC7 among the plurality of pixel areas PXA can be about 5.049 pL.

[0143] Taking the discharge amount of the nozzle corresponding to the pixel area located in the first row PR1 and the second column PC2 among the plurality of pixel areas PXA as an example, the front discharge amount (about 5 pL) can be increased by a percentage (for example, about 0.67%) of the absolute value of the correction number 0.67 (the correction number in the first row CR1 and the second column CC2 of the correction sequence CSQ) and adjusted to about 5.033 pL. For example, in the rear discharge amount AV, the discharge amount corresponding to the pixel area in the first row PR1 and the second column PC2 among the plurality of pixel areas PXA can be about 5.033 pL.

[0144] Taking the discharge amount of the nozzle corresponding to the pixel area located in the first row PR1 and the sixth column PC6 among the plurality of pixel areas PXA as an example, the front discharge amount (about 5 pL) can be reduced by a percentage (for example, about 1.2%) of the absolute value of the correction number of about -1.2 (the correction number in the first row CR1 and the sixth column CC6 of the correction sequence CSQ) and adjusted to about 4.94 pL. For example, in the rear discharge amount AV, the discharge amount corresponding to the pixel area in the first row PR1 and the sixth column PC6 among the plurality of pixel areas PXA can be about 4.94 pL.

[0145] In this way, the controller CON can adjust the discharge amount of the plurality of nozzles NZ corresponding to the plurality of pixel areas PXA. Accordingly, the discharge amount of the plurality of nozzles NZ corresponding to the plurality of pixel areas PXA may be expressed as a rear discharge amount AV.

[0146] Figure 8 It shows that according to Figure 7 Schematic diagram of the amount of droplets discharged into a plurality of pixel regions before the discharge amount. Fig. 9 It shows that according to Figure 7 Schematic diagram of the amount of droplets discharged to multiple pixel areas after the discharge amount.

[0147] First, refer to Figure 7 and Figure 8 , in the front discharge volume BV, the discharge volume of the nozzle corresponding to the pixel area located in the seventh column PC7 among the plurality of pixel areas PXA may be about 4.95 pL, and the discharge volume of the nozzle corresponding to the remaining pixel areas PXA may be about 5 pL. If a total of four droplets IK are discharged in one pixel area, as Figure 8 As shown in , the discharge amount of the droplets finally discharged into each of the multiple pixel areas located in the seventh column PC7 may be about 19.80pL, and the discharge amount of the droplets finally discharged into each of the multiple remaining pixel areas may be about 20.00pL. In this case, due to the relative difference in the discharge amount, stains such as cloud spots may appear in the portion corresponding to the pixel area of ​​the seventh column PC7. In particular, in the front discharge amount BV, the inkjet process may be performed without identifying the difference in the discharge amount of each nozzle due to an error that occurs when the discharge amount of the multiple nozzles NZ is measured by a measuring device or the like. Therefore, it is desirable to pre-adjust the discharge amount of the multiple nozzles NZ by considering the error range that may occur when measuring the discharge amount of the nozzles NZ to prevent the occurrence of stains.

[0148] Also refer to Fig. 9 , according to the implementation, can be based on a variable range (VR, Figure 3 in), measurement error range (MER, in Figure 3 in) and based on the initial sequence (ISQ, in Figure 3and Figure 4 The calibration sequence (CSQ, in Figure 3 and Figure 5 to adjust multiple nozzles (NZ, in Figure 1 and Figure 2 Accordingly, based on the rear discharge amount AV, the discharge amount of the droplets finally discharged to each of the plurality of pixel areas PXA can be relatively uniform. For example, a phenomenon in which there is a relative difference in the discharge amount of the droplets discharged to the pixel areas in a specific column among the plurality of pixel areas PXA can be prevented. Accordingly, the occurrence of stains such as cloud spots in the portion corresponding to the pixel areas of the specific column can be prevented.

[0149] Fig.10 It is shown that the use Figure 1 Schematic flow chart of an inkjet printing method of an inkjet printing device.

[0150] In the following, reference is made to Fig.10 , we will briefly describe the use of Figure 1 Inkjet printing method of inkjet printing device. Figures 1 to 9 Duplicate descriptions will be omitted or simplified.

[0151] Reference Figure 1 , Figure 3 and Fig.10 According to an embodiment, an inkjet printing method may include: generating an initial sequence ISQ (S10); generating a correction sequence CSQ by correcting the initial sequence ISQ based on a variable range VR and a measurement error range MER (S20); and discharging droplets IK to a plurality of pixel areas PXA while adjusting a discharge amount of each nozzle NZ based on the correction sequence CSQ (S30).

[0152] When generating the initial sequence ISQ (S10), the initial sequence ISQ may be generated by arranging a plurality of initial numbers in a matrix form. The initial sequence ISQ may be generated in consideration of spatial frequency. Specifically, in the initial sequence ISQ, for each absolute value, the number of initial numbers having the same absolute value among the plurality of initial numbers may be the same or similar. In an embodiment, an error distribution method may be used as an algorithm for generating the initial sequence ISQ. For example, an FM mask method may be used as an algorithm for generating the initial sequence ISQ.

[0153] When generating the correction sequence CSQ (S20), the variable range VR, the measurement error range MER and the initial sequence ISQ may be input to the input part IP. Thereafter, the correction sequence CSQ may be generated based on the variable range VR, the measurement error range MER and the initial sequence ISQ using the calculation part CP.

[0154] When generating the correction sequence CSQ ( S20 ), the variable range VR input to the input part IP may be −A% to +A%, and the measurement error range MER input to the input part IP may be −B% to +B%.

[0155] When generating the correction sequence CSQ ( S20 ), the calculation part CP may correct the maximum value among the plurality of initial numbers in the initial sequence ISQ to the number calculated by Formula 1.

[0156] [Formula 1]

[0157] AB

[0158] The calculation part CP may correct the minimum value among the plurality of initial numbers in the initial sequence ISQ to the number calculated by Formula 2.

[0159] [Formula 2]

[0160] -(AB)

[0161] For the remaining numbers other than the maximum value and the minimum value among the multiple initial numbers, the calculation part CP can correct each of the multiple remaining numbers to a number at a point between -(AB) and +(AB) corresponding to each point of the multiple remaining numbers between the maximum value and the minimum value.

[0162] For example, in the case where the ratio of any one of the remaining numbers to the difference between the maximum value and the minimum value is C, the calculation part CP may correct the remaining number to the number calculated by Formula 3.

[0163] [Formula 3]

[0164] (AB)x(2C-1)

[0165] As a result, the plurality of correction numbers of the correction sequence CSQ generated when generating the correction sequence CSQ ( S20 ) may include the number calculated by Formula 1, the number calculated by Formula 2, and the number calculated by Formula 3.

[0166] In an embodiment, when the measurement error range MER is a negligible small range (for example, when B is less than 1), when generating the correction sequence CSQ (S20), the calculation unit CP may correct the maximum value among the multiple initial numbers in the initial sequence ISQ to A, may correct the minimum value among the multiple initial numbers in the initial sequence ISQ to -A, and may correct the remaining numbers among the multiple initial numbers to the numbers calculated by Formula 4.

[0167] [Formula 4]

[0168] A x(2C-1)

[0169] For example, in the case where the measurement error range MER is a negligibly small range, the calculation part CP may generate the correction sequence CSQ by considering only the variable range VR without considering the measurement error range MER.

[0170] When the droplets IK are discharged to the plurality of pixel areas PXA ( S30 ), the discharge amount of each nozzle NZ may be adjusted based on the correction sequence CSQ.

[0171] First, the correction numbers in the correction sequence CSQ may correspond to the plurality of pixel regions PXA. If the number of rows and columns of the correction sequence CSQ is smaller than the number of rows and columns of the plurality of pixel regions PXA, the correction numbers may correspond to the plurality of pixel regions PXA by repeatedly arranging the correction sequence CSQ.

[0172] Afterwards, the discharge amount of the nozzle corresponding to the pixel area among the plurality of pixel areas PXA may be adjusted based on the corresponding correction number. For example, when the correction number is a positive number, the discharge amount of the nozzle corresponding to the pixel area may be increased by a percentage of the absolute value of the corresponding correction number. For example, when the correction number is a negative number, the discharge amount of the nozzle corresponding to the pixel area may be reduced by a percentage of the absolute value of the corresponding correction number.

[0173] At this time, the discharge amount of the nozzle can be adjusted by changing the driving waveform signal applied to the nozzle whose discharge amount needs to be adjusted.

[0174] Specifically, the correction sequence CSQ may be transmitted to the output part OP, and the control signal CS may be output by the output part OP based on the correction sequence CSQ. The waveform generating part WS that has received the control signal CS may generate a changed drive waveform signal DS, and the changed drive waveform signal DS may be applied to the nozzle NZ that needs to adjust the discharge amount.

[0175] In an embodiment, in the process of adjusting the discharge amount of each nozzle, the amplitude of the voltage of the driving interval of the driving waveform signal applied to the nozzle whose discharge amount needs to be adjusted may be changed. For example, the amplitude of the voltage of the driving interval of the driving waveform signal applied to the nozzle whose discharge amount needs to be increased may be increased. The amplitude of the voltage of the driving interval of the driving waveform signal applied to the nozzle whose discharge amount needs to be reduced may be reduced. However, the present disclosure is not necessarily limited to this.

[0176] In an embodiment, in the process of adjusting the discharge amount of each nozzle, the length of the driving interval of the driving waveform signal applied to the nozzle whose discharge amount needs to be adjusted may be changed. For example, the length of the driving interval of the driving waveform signal applied to the nozzle whose discharge amount needs to be increased may be extended. The length of the driving interval of the driving waveform signal applied to the nozzle whose discharge amount needs to be reduced may be shortened. However, the present disclosure is not necessarily limited thereto.

[0177] In an embodiment, in the process of adjusting the discharge amount of each nozzle, the frequency of the driving interval of the driving waveform signal applied to the nozzle whose discharge amount needs to be adjusted may be changed. For example, the frequency of the driving interval of the driving waveform signal applied to the nozzle whose discharge amount needs to be increased may be increased. The frequency of the driving interval of the driving waveform signal applied to the nozzle whose discharge amount needs to be reduced may be reduced. However, the present disclosure is not necessarily limited thereto.

[0178] According to the inkjet printing method according to the present embodiment, the discharge amount of the plurality of nozzles can be adjusted in advance by taking into account the measurement error that may occur when the discharge amount of the plurality of nozzles is measured by a measuring device or the like. Accordingly, the difference in the discharge amount of each nozzle that has not been identified due to the measurement error in the discharge amount of the plurality of nozzles can be easily corrected.

[0179] Accordingly, the discharge amount of the droplets finally discharged to each of the plurality of pixel regions by the inkjet printing method according to the embodiment can be relatively uniform. For example, a phenomenon in which there is a relative difference in the discharge amount of the droplets discharged to the pixel region in a specific column among the plurality of pixel regions can be prevented. Accordingly, the occurrence of stains such as clouding in the portion corresponding to the pixel region of the specific column can be prevented. Accordingly, the reliability of the inkjet printing process can be improved.

[0180] The present disclosure can be applied to display panel inspection devices of various display devices. For example, the present disclosure can be applied to display panel inspection devices of various display devices such as display devices for vehicles, ships and aircraft, display devices for portable communication devices, display devices for exhibitions or information transmission, medical display devices and the like.

[0181] The foregoing is an illustration of the embodiments and should not be construed as limiting thereof. Although some embodiments have been described, it will be readily appreciated by those skilled in the art that many modifications can be made to the embodiments without substantially departing from the novel teachings and advantages of the inventive concept. Accordingly, all such modifications are intended to be included within the scope of the inventive concept as defined in the claims. Therefore, it should be understood that the foregoing is an illustration of various embodiments and should not be construed as being limited to the specific embodiments disclosed, and it should be understood that modifications to the disclosed embodiments as well as other embodiments are intended to be included within the scope of the appended claims.

Claims

1. An inkjet printing method comprising: generating an initial sequence in which a plurality of initial numbers are arranged in a matrix form; generating a correction sequence by correcting the plurality of initial numbers with a plurality of correction numbers based on a variable range of the amount of liquid droplets ejected into a plurality of pixel regions and a measurement error range of discharge amounts of a plurality of nozzles that discharge liquid droplets into the plurality of pixel regions; as well as Liquid droplets are discharged to the plurality of pixel areas while adjusting the discharge amount of each nozzle based on the correction sequence.

2. The inkjet printing method according to claim 1, wherein: The variable range is -A% to +A%, the measurement error range is -B% to +B%, each of A and B is a positive number, and B is smaller than A, and When generating the correction sequence, the maximum value among the plurality of initial numbers is corrected to a number calculated by the following formula 1, [Formula 1] AB.

3. The inkjet printing method according to claim 2, wherein: When generating the correction sequence, the minimum value among the plurality of initial numbers is corrected to a number calculated by the following formula 2: [Formula 2] -(AB).

4. The inkjet printing method according to claim 3, wherein: For a plurality of remaining numbers other than the maximum value and the minimum value among the plurality of initial numbers, when C is a ratio of any remaining number to a difference between the maximum value and the minimum value, the remaining number is corrected to a number calculated by the following formula 3 when generating the correction sequence, [Formula 3] (AB)x(2C-1).

5. The inkjet printing method according to claim 1, wherein: The variable range is -A% to +A%, the measurement error range is -B% to +B%, each of A and B is a positive number, and B is less than 1, When generating the correction sequence, the maximum value among the plurality of initial numbers is corrected to A, and the minimum value among the plurality of initial numbers is corrected to -A, and For a plurality of remaining numbers other than the maximum value and the minimum value among the plurality of initial numbers, when C is a ratio of any remaining number to a difference between the maximum value and the minimum value, the remaining number is corrected to a number calculated by the following formula 4 when generating the correction sequence, [Formula 4] A x(2C-1).

6. The inkjet printing method according to claim 1, wherein: The plurality of correction numbers correspond to the plurality of pixel areas when the droplets are discharged to the plurality of pixel areas.

7. The inkjet printing method according to claim 6, wherein: When the liquid droplets are discharged to the plurality of pixel areas, a discharge amount of a nozzle corresponding to a pixel area among the plurality of pixel areas is adjusted based on a correction number corresponding to the pixel area.

8. The inkjet printing method according to claim 7, wherein: The discharge amount of the nozzle corresponding to the pixel area is increased or decreased by a percentage of the absolute value of the correction number.

9. The inkjet printing method according to claim 8, wherein: In a case where the correction number is a positive number, the discharge amount of the nozzle corresponding to the pixel area is increased by a percentage of the absolute value of the correction number.

10. The inkjet printing method according to claim 8, wherein: In a case where the correction number is a negative number, the discharge amount of the nozzle corresponding to the pixel area is reduced by a percentage of the absolute value of the correction number.

11. The inkjet printing method according to claim 1, wherein: Each of the plurality of initial numbers is an integer greater than or equal to 0.

12. The inkjet printing method according to claim 1, wherein: Each of the plurality of initial numbers has a spatial frequency in the initial sequence, and A difference in spatial frequency between the plurality of initial numbers is 10% or less.

13. The inkjet printing method according to claim 12, wherein: The plurality of initial numbers have the same spatial frequency in the initial sequence.

14. The inkjet printing method according to claim 1, wherein: When discharging liquid droplets to the plurality of pixel regions, driving waveform signals applied to the plurality of nozzles are changed to adjust the discharge amounts of the plurality of nozzles.

15. The inkjet printing method according to claim 14, wherein: The driving waveform signal has a driving interval and non-driving intervals before and after the driving interval, and When the droplets are discharged to the plurality of pixel regions, the amplitude of the voltage of the driving interval is changed.

16. The inkjet printing method according to claim 14, wherein: The driving waveform signal has a driving interval and non-driving intervals before and after the driving interval, and When the droplets are discharged to the plurality of pixel regions, the length of the driving interval is changed.

17. The inkjet printing method according to claim 14, wherein: The driving waveform signal has a driving interval and non-driving intervals before and after the driving interval, and When the droplets are discharged to the plurality of pixel regions, the frequency of the driving interval included in the driving waveform signal is changed.

18. The inkjet printing method according to claim 1, wherein: The plurality of nozzles form a nozzle row, and The discharge amount of each of the plurality of nozzles is individually adjusted when discharging liquid droplets to the plurality of pixel regions.

19. An inkjet printing device comprising: a plurality of nozzles that discharge droplets to a plurality of pixel regions; an input portion, at which a measurement error range of the discharge amounts of the plurality of nozzles is input; a calculation unit that generates a correction sequence based on the data input to the input unit, in which a plurality of correction numbers are arranged in a matrix form; a waveform generating section that generates a driving waveform signal applied to the plurality of nozzles; as well as An output unit outputs a control signal to the waveform generation unit based on the correction sequence.

20. The inkjet printing apparatus according to claim 19, wherein: The input section also inputs a variable range of the amount of liquid droplets discharged to the plurality of pixel regions.

21. The inkjet printing apparatus according to claim 20, wherein: The input unit further inputs an initial sequence in which a plurality of initial numbers corresponding to the plurality of pixel regions are arranged in a matrix form.

22. The inkjet printing apparatus according to claim 21, wherein: The calculation section corrects the plurality of initial numbers using the plurality of correction numbers based on the variable range and the measurement error range.

23. The inkjet printing apparatus according to claim 22, wherein: The variable range is -A% to +A%, the measurement error range is -B% to +B%, each of A and B is a positive number, and B is smaller than A, and The plurality of correction numbers include a number calculated by the following formula 1 and a number calculated by the following formula 2, [Formula 1] AB [Formula 2] -(AB).

24. The inkjet printing apparatus according to claim 23, wherein: For a plurality of remaining numbers other than the maximum value and the minimum value among the plurality of initial numbers, in the case where C is a ratio of any remaining number to a difference between the maximum value and the minimum value, the plurality of correction numbers further include a number calculated by the following formula 3, [Formula 3] (AB)x(2C-1).

25. The inkjet printing apparatus according to claim 22, wherein: The variable range is -A% to +A%, the measurement error range is -B% to +B%, each of A and B is a positive number, and B is less than 1, and For a plurality of remaining numbers other than the maximum value and the minimum value among the plurality of initial numbers, in the case where C is a ratio of any remaining number to a difference between the maximum value and the minimum value, the plurality of correction numbers include A, -A, and a number calculated by the following formula 4, [Formula 4] A x(2C-1).

26. The inkjet printing apparatus according to claim 19, wherein: The driving waveform signal has a driving interval and non-driving intervals before and after the driving interval, and The control signal includes at least one of: a first control signal controlling an amplitude of a voltage of the driving interval, a second control signal controlling a length of the driving interval, and a third control signal controlling a frequency of the driving interval included in the driving waveform signal.

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