Color correction method and system based on multi-nozzle consistency

Abstract

This application discloses a color correction method and system based on multi-printhead consistency. The method includes: acquiring the standard color parameters of a reference printhead, the actual color parameters of a target printhead, the ambient temperature and humidity, and the actual ink viscosity; calculating multidimensional deviations and comprehensive color differences based on the standard and actual color parameters, and determining color compensation based on constraints; if color compensation is required, calculating multidimensional compensation factors based on the ambient temperature and humidity and the actual ink viscosity, and calculating multidimensional compensation coefficients based on multidimensional deviations; calculating the driving parameters of the target printhead based on the multidimensional compensation coefficients and factors, and adjusting the target printhead based on the driving parameters; calculating the corrected comprehensive color difference based on the corrected actual color parameters; and performing graded closed-loop processing based on the corrected comprehensive color difference. This application improves multi-printhead color consistency and ensures long-term stable and high-precision printing.

Description

Technical Field

[0001] This invention relates to the field of color control technology for inkjet printing equipment, and specifically to a color correction method and system based on the consistency of multiple printheads. Background Technology

[0002] As inkjet printing equipment develops towards wider formats and higher speeds, multi-head parallel operation has become the mainstream configuration. Due to individual differences in nozzle diameter and piezoelectric ceramic response speed during the manufacturing process, wear and tear, clogging, and aging of the drive circuit occur during use. At the same time, changes in ambient temperature and humidity alter ink viscosity and surface tension, and installation errors can lead to nozzle position deviations and uneven ink supply pressure. These factors collectively cause the core problem of poor color consistency in multi-head inkjet printing equipment, seriously affecting the quality of printed products.

[0003] Currently, most multi-printhead color control methods rely on manual calibration, which has a long calibration cycle, low accuracy, and is entirely dependent on manual operation, resulting in low efficiency. Moreover, during the compensation process, only a single parameter is used for compensation. For example, patent CN202021856789.3 only compensates for brightness or ink volume, ignoring hue and saturation deviations. The calibration dimension is singular and cannot completely solve the problem of color consistency.

[0004] During the calibration process, the calibration methods are crude and lack a closed loop, often relying on fixed parameter compensation or manual adjustment. They lack an automatic iterative hierarchical closed-loop mechanism, resulting in low calibration efficiency and poor accuracy. Repeated calibrations often fail to meet the standards. For example, patent CN202510251990.4 does not involve color parameter adjustment and requires machine downtime for testing, affecting production progress. Patent CN202310856789.1 uses fixed parameters, which cannot adapt to dynamic scenarios such as printhead aging and ink viscosity changes. Patent CN202110389765.2 requires manual printing of color cards for calibration, lacking dynamic adjustment capabilities and exhibiting poor adaptability.

[0005] Therefore, how to achieve consistent color correction across multiple printheads is a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0006] In order to solve the above-mentioned technical problems, this application proposes the following technical solution: In a first aspect, embodiments of this application provide a color correction method based on multi-printer consistency, comprising: The standard color parameters of the reference printhead under standard conditions, the actual color parameters of the target printhead under actual working conditions, the ambient temperature and humidity, and the actual ink viscosity were obtained respectively. The multidimensional deviation and comprehensive color difference are calculated based on the standard color parameters and the actual color parameters, and the color compensation is judged in combination with the constraints. If it is determined that color compensation is required, then the multi-dimensional compensation factor is calculated based on the ambient temperature and humidity and the actual ink viscosity, and the multi-dimensional compensation coefficient is calculated in combination with the multi-dimensional deviation. After calculating the driving parameters of the target nozzle based on the multidimensional compensation coefficient and the multidimensional compensation factor, the operating parameters of the target nozzle are adjusted based on the driving parameters. After the adjustment is completed, the overall color difference after correction is calculated based on the corrected actual color parameters; A graded closed-loop process is performed based on the calculated corrected overall color difference.

[0007] In one possible implementation, multidimensional deviation and comprehensive color difference are calculated based on the standard color parameters and the actual color parameters, and color compensation is judged in conjunction with constraints, including: The brightness deviation, red-green hue deviation, yellow-blue hue deviation, saturation deviation, and overall color difference are calculated based on the standard color parameters and the actual color parameters, respectively. The overall color difference is compared with preset conditions. When the overall color difference is greater than the preset conditions, color compensation is triggered.

[0008] In one possible implementation, the formulas for calculating the lightness deviation, red-green hue deviation, yellow-blue hue deviation, saturation deviation, and overall color difference based on the standard color parameters and the actual color parameters are as follows: , , , in, For the first The brightness deviation between each nozzle and the reference nozzle. For the first The actual color brightness value output by each printhead. The standard brightness value of the reference nozzle. For the first The red-green phase deviation between the individual nozzle and the reference nozzle For the first The actual a-axis color value output by each printhead. The standard a-axis color value of the reference printhead. For the first The actual b-axis color coordinate value output by each printhead. The standard b-axis color coordinate value of the reference printhead. For the first The yellow-blue phase deviation between each nozzle and the reference nozzle, For the first Saturation deviation between individual nozzles and the reference nozzle To account for color differences.

[0009] In one possible implementation, the formula for calculating the multi-dimensional compensation factor based on the ambient temperature and humidity and the actual ink viscosity is as follows: in, As the density compensation factor, For ink viscosity correction factor, This is a temperature correction factor. For ambient temperature, This represents the actual ink viscosity. Standard ink viscosity, The average optical density of the color patch printed by the reference printhead under standard conditions. For the first The measured density of each nozzle.

[0010] In one possible implementation, the formulas for calculating the multidimensional compensation coefficients are as follows: in, This is the brightness compensation coefficient. The red-green phase compensation coefficient is... The yellow-blue phase compensation coefficient is... This is the saturation compensation coefficient. This is a temperature correction factor. This refers to the nozzle aging coefficient. For the first The brightness deviation between each nozzle and the reference nozzle. The viscosity coefficient is the factor affecting ink viscosity. For the first The red-green phase deviation between the individual nozzle and the reference nozzle For the first The yellow-blue phase deviation between each nozzle and the reference nozzle, For the first The saturation deviation between each nozzle and the reference nozzle.

[0011] In one possible implementation, the formula for calculating the driving parameters of the target nozzle based on the three-dimensional compensation coefficient and the multi-dimensional compensation factor is as follows: in, For the first Drive voltage after nozzle calibration As the reference drive voltage, This is the brightness compensation coefficient. This is the saturation compensation coefficient. The current ambient temperature. For the first The spray frequency after nozzle calibration As the reference injection frequency, The red-green phase compensation coefficient is... The yellow-blue phase compensation coefficient is... For the first Single droplet ink volume after printhead calibration Based on the amount of ink per drop, The viscosity coefficient is the factor affecting ink viscosity. This refers to the nozzle aging coefficient. For the first Ink supply pressure after printhead calibration The reference ink supply pressure.

[0012] In one possible implementation, the formula for calculating the corrected overall color difference based on the corrected actual color parameters is as follows: , , , in, For the first Overall color difference after individual printhead calibration For the corrected first The difference in brightness between the individual nozzles and the reference nozzle. For the corrected first Red-green deviation of each nozzle from the reference nozzle For the corrected first The yellow-blue deviation between each nozzle and the reference nozzle For the corrected first The actual color brightness value output by each printhead. The standard brightness value of the reference nozzle. For the corrected first The actual a-axis color value output by each printhead. The standard a-axis color value of the reference printhead. For the corrected first The actual b-axis color coordinate value output by each printhead. The standard b-axis color coordinate value is used for the reference printhead.

[0013] In one possible implementation, a graded closed-loop processing is performed based on the calculated corrected comprehensive color difference, including: The corrected overall color difference is compared with the set compensation trigger threshold; If the corrected overall color difference is less than or equal to the set compensation trigger threshold, it is deemed qualified and the current compensation parameters are maintained. If the corrected overall color difference is greater than the set compensation trigger threshold and less than or equal to the first preset value, then a second correction is performed, and the compensation coefficient is updated iteratively in a fast manner. If the corrected overall color difference is greater than the first preset value and less than or equal to the second preset value, then depth correction is performed to strengthen the correction factor weight and adjust the ink supply pressure offset. If the corrected overall color difference is greater than the second preset value or the number of depth correction failures reaches the preset value, a fault alarm will be triggered and the target nozzle will be shut down.

[0014] Secondly, embodiments of this application provide a color correction system based on multi-head consistency, comprising: The acquisition module is used to acquire the standard color parameters of the reference printhead under standard conditions, the actual color parameters of the target printhead under actual working conditions, the ambient temperature and humidity, and the actual ink viscosity. The compensation judgment module is used to calculate the multidimensional deviation and comprehensive color difference based on the standard color parameters and the actual color parameters, and to judge the color compensation in combination with the constraint conditions. The compensation calculation module is used to calculate the multi-dimensional compensation factor based on the ambient temperature and humidity and the actual ink viscosity, and to calculate the multi-dimensional compensation coefficient in combination with the multi-dimensional deviation. The adjustment module is used to calculate the driving parameters of the target nozzle based on the multidimensional compensation coefficient and the multidimensional compensation factor, and then adjust the working parameters of the target nozzle based on the driving parameters. The calibration calculation module is used to calculate the overall color difference after calibration based on the actual color parameters after calibration. The closed-loop processing module is used to perform graded closed-loop processing based on the corrected comprehensive color difference.

[0015] Compared with the prior art, the beneficial effects of this application are as follows: This application adopts a three-dimensional color compensation model of brightness-hue-saturation, combined with a full-dimensional pre-fault and fault judgment system. Each dimension compensation factor performs its own function without redundant correction. After correction, the overall color difference is less than the set threshold, completely eliminating color banding and discontinuity defects between nozzles. The color uniformity is improved by 40% compared with the existing technology. Over-constraint deviation can be warned and fault alarmed in real time, meeting the industrial-grade high-precision requirements of different scenarios.

[0016] This application constructs a real-time closed-loop calibration system with a single calibration cycle of less than 5 seconds, requiring no downtime for offline operation, improving calibration efficiency by 90%, and overall production efficiency by 30%. It adopts a gradient update mechanism of coarse and fine updates to avoid data execution conflicts, further improving calibration response efficiency and solving the core problems of long calibration cycles and production impact in existing technologies.

[0017] This application employs a weighted iterative and gradient descent method to self-learn and update compensation coefficients, adapting to long-term aging and wear of the printhead, continuously maintaining high color consistency, and extending the effective service life of the equipment. Simultaneously, this application features a multi-dimensional deviation warning and over-limit alarm shutdown mechanism, which can automatically shut down faulty printheads and switch to backup printheads, effectively protecting hardware and reducing unplanned downtime.

[0018] This application features fully automated execution without human intervention, enabling real-time warning of nozzle deviation, precise fault location and automatic handling. It supports the storage of multiple calibration records and export in multiple formats, as well as retrieval and traceability, reducing equipment maintenance costs and the threshold for manual operation. The human-machine interface is highly visual and supports manual adjustment of parameters such as calibration thresholds and update cycles, adapting to different equipment models and production scenarios. Attached Figure Description

[0019] Figure 1 A schematic flowchart illustrating a color correction method based on multi-head consistency provided in an embodiment of this application; Figure 2 This is a schematic diagram of a color correction system based on multi-head consistency provided in an embodiment of this application. Detailed Implementation

[0020] The present solution will now be described in conjunction with the accompanying drawings and specific embodiments.

[0021] Figure 1 A flowchart illustrating a color correction method based on multi-head consistency provided in this application embodiment is shown below. Figure 1 This embodiment of a color correction method based on multi-nozzle consistency includes: S101 acquires the standard color parameters of the reference printhead under standard conditions, the actual color parameters of the target printhead under actual working conditions, the ambient temperature and humidity, and the actual ink viscosity.

[0022] In this embodiment, a comprehensive color difference fluctuation of less than or equal to 0.3 is selected. A printhead with an ink output stability greater than or equal to 98% is used as the reference printhead, or a manually specified reference printhead can be used. The standard color parameters of the reference printhead under standard conditions are obtained. , collect the first The color data of 100 pixels within a 5mm x 5mm color block area printed by each printhead are averaged and used as the actual color data of that printhead. At the same time, the ambient temperature and humidity and the actual ink viscosity were obtained.

[0023] S102 calculates the multidimensional deviation and comprehensive color difference based on standard color parameters and actual color parameters, and judges the color compensation in combination with constraints.

[0024] In this embodiment, the brightness deviation, red-green hue deviation, yellow-blue hue deviation, saturation deviation, and overall color difference are calculated based on standard color parameters and actual color parameters, respectively. The calculation formulas are as follows: , , , in, For the first The brightness deviation between each nozzle and the reference nozzle. For the first The actual color brightness value output by each printhead. The standard brightness value of the reference nozzle. For the first The red-green phase deviation between the individual nozzle and the reference nozzle For the first The actual a-axis color value output by each printhead. The standard a-axis color value of the reference printhead. For the first The actual b-axis color coordinate value output by each printhead. The standard b-axis color coordinate value of the reference printhead. For the first The yellow-blue phase deviation between each nozzle and the reference nozzle, For the first Saturation deviation between individual nozzles and the reference nozzle To account for color differences.

[0025] The overall color difference is compared with the preset conditions. When the overall color difference is greater than... At that time, color compensation is triggered.

[0026] S103, if it is determined that color compensation is required, then the multi-dimensional compensation factor is calculated based on the ambient temperature and humidity and the actual ink viscosity, and the multi-dimensional compensation coefficient is calculated in combination with the multi-dimensional deviation.

[0027] In this embodiment, the multi-dimensional compensation factors include density compensation factor, ink viscosity compensation factor, and temperature correction factor; the multi-dimensional compensation coefficients include brightness compensation coefficient, red-green hue compensation coefficient, yellow-blue hue compensation coefficient, and saturation compensation coefficient, wherein the calculation formulas are as follows: when or When the density deviation exceeds the compensation range, an early warning is issued. or When this occurs, an alarm is triggered and the machine is shut down.

[0028] when At that time, an ink viscosity deviation warning is issued. or This triggers an alarm, stops the machine, and prompts the user to check the ink viscosity.

[0029] in, As the density compensation factor, For ink viscosity correction factor, This is a temperature correction factor. For ambient temperature, This represents the actual ink viscosity. Standard ink viscosity, The average optical density of the color patch printed by the reference printhead under standard conditions. For the first The measured density of each nozzle.

[0030] when Issue an environmental temperature deviation warning when or This triggers an alarm, stops the machine, and prompts the user to adjust the printing environment.

[0031] in, This is the brightness compensation coefficient. The red-green phase compensation coefficient is... The yellow-blue phase compensation coefficient is... This is the saturation compensation coefficient. This is a temperature correction factor. This refers to the nozzle aging coefficient. For the first The brightness deviation between each nozzle and the reference nozzle. The viscosity coefficient is the factor affecting ink viscosity. For the first The red-green phase deviation between the individual nozzle and the reference nozzle For the first The yellow-blue phase deviation between each nozzle and the reference nozzle, For the first The saturation deviation between each nozzle and the reference nozzle.

[0032] when At that time, a saturation deviation warning is issued. When this occurs, an alarm is triggered and depth correction is initiated.

[0033] S104: After calculating the driving parameters of the target nozzle based on the multidimensional compensation coefficient and multidimensional compensation factor, the working parameters of the target nozzle are adjusted according to the driving parameters.

[0034] In this embodiment, the driving parameters include driving voltage, jetting frequency, single droplet ink volume, and ink supply pressure, and the calculation formulas are as follows: in, For the first Drive voltage after nozzle calibration As the reference drive voltage, This is the brightness compensation coefficient. This is the saturation compensation coefficient. The current ambient temperature. For the first The spray frequency after nozzle calibration As the reference injection frequency, The red-green phase compensation coefficient is... The yellow-blue phase compensation coefficient is... For the first Single droplet ink volume after printhead calibration Based on the amount of ink per drop, is the ink viscosity influence coefficient, is the nozzle aging coefficient, is the ink supply pressure after calibration for the th nozzle, and

[0035] S105. After the adjustment is completed, calculate the corrected comprehensive color difference according to the actual color parameters after calibration.

[0036] In this embodiment, after adjusting the working parameters of the target nozzle according to the driving parameters, re-collect the color data of 100 pixel points in a 5mm×5mm color block area within the printing area of the th nozzle, and calculate the corrected comprehensive color difference according to the actual color parameters after calibration. The calculation formula is: , , , where is the corrected comprehensive color difference for the th nozzle, is the lightness difference between the th nozzle after calibration and the reference nozzle, is the red-green deviation between the th nozzle after calibration and the reference nozzle, is the yellow-blue deviation between the th nozzle after calibration and the reference nozzle, is the actual output color lightness value of the th nozzle after calibration, is the standard lightness value of the reference nozzle, is the actual output a-axis color value of the th nozzle after calibration, is the standard a-axis color value of the reference nozzle, is the actual output b-axis color coordinate value of the th nozzle after calibration, is the standard b-axis color coordinate value of the reference nozzle.

[0037] S106. Perform hierarchical closed-loop processing according to the calculated corrected comprehensive color difference.

[0038] In this embodiment, compare the corrected comprehensive color difference with the set compensation trigger threshold. When the corrected comprehensive color difference is less than or equal to the set compensation trigger threshold, it is determined to be qualified and the current compensation parameters are maintained. If the corrected comprehensive color difference is greater than the set compensation trigger threshold and less than or equal to 1.5 Perform a secondary correction and rapidly iterate and update the compensation coefficients. If the overall color difference after correction is greater than 1.5... and less than or equal to 2 If the error persists, a depth correction is performed, increasing the weight of the correction factor and adjusting the ink supply pressure offset. If the overall color difference after correction is greater than 2... If the number of depth correction failures reaches a preset value, a fault alarm will be triggered and the target nozzle will be shut down.

[0039] In this embodiment, the following is satisfied: or or , or , or , or , or , and An early warning will be issued under any condition, without interrupting the printing process, and the deviation will be continuously monitored.

[0040] satisfy or or , or , or , or , or , If three depth calibrations fail, or the calculated values ​​of the drive parameters exceed hardware constraints and cannot be calibrated under any condition, an alarm will be triggered and the faulty nozzle will be shut down. If a backup nozzle is configured, it will automatically switch to the faulty nozzle and prompt for manual maintenance.

[0041] Furthermore, embodiments of this application also include self-learning optimization, which uses a weighted iterative self-learning formula to update the compensation coefficients. The calculation formula is as follows: : in, This is the current compensation coefficient. These are the new compensation coefficients calculated in this gradient descent iteration. The Markov chain self-learning logic, based on the average of the past 5 compensation coefficients, predicts the nozzle aging trend based on historical correction data and adjusts the coefficient weights in advance. Every 100 corrections, the system automatically updates the weighted coefficients using gradient descent to adapt to the long-term aging and wear of the nozzle.

[0042] Taking a 16-printer, 4-pass UV wide-format inkjet printer as an example, the basic parameter configuration is as follows: 16 Seiko SPT35pl piezoelectric UV printheads, printhead spacing 8mm, reference printhead number 8, and standard color parameters are as follows. Reference drive parameters , , , The ambient temperature was 26℃, the humidity was 55%, the standard viscosity was 20 mPa·s, the actual viscosity was 21 mPa·s, the regular update cycle was 10 sheets, and the compensation trigger threshold was... Pre-fault or fault is determined based on all dimensions.

[0043] First, initialization is performed. The 16 nozzles operate according to the baseline drive parameters, with all compensation coefficient matrices set to 1 and the correction threshold set to [value missing]. The pre-fault or fault judgment rules have been loaded. Actual data S3 = {83, 3.2, 3.8, 1.40} for a 5mm × 5mm color block printed by printhead #3 is collected. Simultaneously, ambient temperature (26℃) and ink viscosity (21 mPa·s) are also collected. Based on the acquired data, calculations are performed on brightness deviation, red-green hue deviation, yellow-blue hue deviation, saturation deviation, and overall color difference. , Triggering a brightness pre-fault warning. , , , This triggered a saturation fault warning; the overall color difference was 3.418, which is greater than... This triggers color compensation. Subsequently, the density compensation factor, viscosity correction factor, and temperature correction factor are calculated, with results of 0.998, 0.943, and 1.005, respectively. Then, the lightness compensation coefficient, red-green hue compensation coefficient, yellow-blue hue compensation coefficient, and saturation compensation coefficient are calculated, with results of 0.9874, 0.9901, 0.9935, and 1.0260, respectively.

[0044] The driving voltage, jetting frequency, single droplet ink volume, and ink supply pressure of printhead No. 3 were calculated based on multidimensional compensation coefficients and multidimensional compensation factors. The calculated results were 23.7V, 9.90kHz, 5.02pl, and 0.331MPa, respectively. The calibrated driving parameters were then sent to the drive module of printhead No. 3 for real-time adjustment of various parameters and continuous monitoring of the deviation between brightness pre-fault and saturation fault. After calibration, S3'={80.2, 2.1, 3.1, 1.48} was collected. If the printout is deemed acceptable, maintain the current parameters, and remove the brightness and saturation warnings. Repeat the above process every 10 prints according to the detailed update rules, updating and storing the compensation coefficients. When the coarse update conditions are met, automatically calibrate the standard color database. The corrected overall color difference is less than or equal to... It completely eliminates color banding defects between printheads, provides fault-free early warning for all parameters, and eliminates the need for machine downtime during calibration, improving calibration efficiency by 90% and overall production efficiency by 35%. The defect rate is reduced from 8% in existing technologies to below 2%. It is adaptable to the entire temperature range of 0-60℃, and maintains stable color accuracy with no significant drift in the 10-40℃ range. Minor viscosity changes can be corrected in real time. Even after 12 hours of continuous operation, color parameter fluctuations are less than or equal to... There were no downtime due to faults.

[0045] Corresponding to the color correction method based on multi-nozzle consistency provided in the above embodiments, this application also provides an embodiment of a color correction system based on multi-nozzle consistency.

[0046] See Figure 2 This application provides a color correction system 20 based on multi-head consistency, comprising: The acquisition module 201 is used to acquire the standard color parameters of the reference printhead under standard environment, the actual color parameters of the target printhead under actual working environment, the ambient temperature and humidity, and the actual ink viscosity.

[0047] The compensation judgment module 202 is used to calculate the multidimensional deviation and comprehensive color difference based on the standard color parameters and the actual color parameters, and to judge the color compensation in combination with the constraints.

[0048] The compensation calculation module 203 is used to calculate multi-dimensional compensation factors based on ambient temperature and humidity and actual ink viscosity, and to calculate multi-dimensional compensation coefficients in combination with multi-dimensional deviations.

[0049] The adjustment module 204 is used to calculate the driving parameters of the target nozzle based on the multidimensional compensation coefficient and the multidimensional compensation factor, and then adjust the working parameters of the target nozzle based on the driving parameters.

[0050] The calibration calculation module 205 is used to calculate the calibrated overall color difference based on the calibrated actual color parameters.

[0051] The closed-loop processing module 206 is used to perform graded closed-loop processing based on the calculated corrected comprehensive color difference.

[0052] In this embodiment, "multiple" refers to two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent the existence of A alone, the simultaneous existence of A and B, or the existence of B alone. A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0053] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0054] The above description is merely a specific embodiment of this application. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the protection scope of this application. The protection scope of this application should be determined by the protection scope of the claims.

Claims

1. A color correction method based on multi-head consistency, characterized in that, include: The standard color parameters of the reference printhead under standard conditions, the actual color parameters of the target printhead under actual working conditions, the ambient temperature and humidity, and the actual ink viscosity were obtained respectively. The multidimensional deviation and comprehensive color difference are calculated based on the standard color parameters and the actual color parameters, and the color compensation is judged in combination with the constraints. If it is determined that color compensation is required, then the multi-dimensional compensation factor is calculated based on the ambient temperature and humidity and the actual ink viscosity, and the multi-dimensional compensation coefficient is calculated in combination with the multi-dimensional deviation. After calculating the driving parameters of the target nozzle based on the multidimensional compensation coefficient and the multidimensional compensation factor, the operating parameters of the target nozzle are adjusted based on the driving parameters. After the adjustment is completed, the overall color difference after correction is calculated based on the corrected actual color parameters; A graded closed-loop process is performed based on the calculated corrected overall color difference.

2. The color correction method based on multi-head consistency according to claim 1, characterized in that, The multidimensional deviation and comprehensive color difference are calculated based on the standard color parameters and the actual color parameters, and the color compensation is judged in conjunction with the constraints, including: The brightness deviation, red-green hue deviation, yellow-blue hue deviation, saturation deviation, and overall color difference are calculated based on the standard color parameters and the actual color parameters, respectively. The overall color difference is compared with preset conditions. When the overall color difference is greater than the preset conditions, color compensation is triggered.

3. The color correction method based on multi-head consistency according to claim 2, characterized in that, The formulas for calculating lightness deviation, red-green hue deviation, yellow-blue hue deviation, saturation deviation, and overall color difference based on the standard color parameters and the actual color parameters are as follows: ， ， ， in, For the first The brightness deviation between each nozzle and the reference nozzle. For the first The actual color brightness value output by each printhead. The standard brightness value of the reference nozzle. For the first The red-green phase deviation between the individual nozzle and the reference nozzle For the first The actual a-axis color value output by each printhead. The standard a-axis color value of the reference printhead. For the first The actual b-axis color coordinate value output by each printhead. The standard b-axis color coordinate value of the reference printhead. For the first The yellow-blue phase deviation between each nozzle and the reference nozzle, For the first Saturation deviation between individual nozzles and the reference nozzle To account for color differences.

4. The color correction method based on multi-head consistency according to claim 1, characterized in that, The formula for calculating the multi-dimensional compensation factor based on the ambient temperature and humidity and the actual ink viscosity is as follows: in, As the density compensation factor, For ink viscosity correction factor, This is a temperature correction factor. For ambient temperature, This represents the actual ink viscosity. Standard ink viscosity, The average optical density of the color patch printed by the reference printhead under standard conditions. For the first The measured density of each nozzle.

5. The color correction method based on multi-head consistency according to claim 1, characterized in that, The formulas for calculating the multidimensional compensation coefficients are as follows: in, This is the brightness compensation coefficient. The red-green phase compensation coefficient is... The yellow-blue phase compensation coefficient is... This is the saturation compensation coefficient. This is a temperature correction factor. This refers to the nozzle aging coefficient. For the first The brightness deviation between each nozzle and the reference nozzle. The viscosity coefficient is the factor affecting ink viscosity. For the first The red-green phase deviation between the individual nozzle and the reference nozzle For the first The yellow-blue phase deviation between each nozzle and the reference nozzle, For the first The saturation deviation between each nozzle and the reference nozzle.

6. The color correction method based on multi-head consistency according to claim 1, characterized in that, The formula for calculating the driving parameters of the target nozzle based on the multidimensional compensation coefficient and the multidimensional compensation factor is as follows: in, For the first Drive voltage after nozzle calibration As the reference drive voltage, This is the brightness compensation coefficient. This is the saturation compensation coefficient. The current ambient temperature. For the first The spray frequency after nozzle calibration As the reference injection frequency, The red-green phase compensation coefficient is... The yellow-blue phase compensation coefficient is... For the first Single droplet ink volume after printhead calibration Based on the amount of ink per drop, The viscosity coefficient is the factor affecting ink viscosity. This refers to the nozzle aging coefficient. For the first Ink supply pressure after printhead calibration The reference ink supply pressure.

7. The color correction method based on multi-head consistency according to claim 1, characterized in that, The formula for calculating the corrected overall color difference based on the corrected actual color parameters is as follows: ， ， ， in, For the first Overall color difference after individual printhead calibration For the corrected first The difference in brightness between the individual nozzles and the reference nozzle. For the corrected first Red-green deviation of each nozzle from the reference nozzle For the corrected first The yellow-blue deviation between each nozzle and the reference nozzle For the corrected first The actual color brightness value output by each printhead. The standard brightness value of the reference nozzle. For the corrected first The actual a-axis color value output by each printhead. The standard a-axis color value of the reference printhead. For the corrected first The actual b-axis color coordinate value output by each printhead. The standard b-axis color coordinate value is used for the reference printhead.

8. The color correction method based on multi-head consistency according to claim 1, characterized in that, Based on the calculated corrected overall color difference, a graded closed-loop processing is performed, including: The corrected overall color difference is compared with the set compensation trigger threshold; If the corrected overall color difference is less than or equal to the set compensation trigger threshold, it is deemed qualified and the current compensation parameters are maintained. If the corrected overall color difference is greater than the set compensation trigger threshold and less than or equal to the first preset value, then a second correction is performed, and the compensation coefficient is updated iteratively in a fast manner. If the corrected overall color difference is greater than the first preset value and less than or equal to the second preset value, then depth correction is performed to strengthen the correction factor weight and adjust the ink supply pressure offset. If the corrected overall color difference is greater than the second preset value or the number of depth correction failures reaches the preset value, a fault alarm will be triggered and the target nozzle will be shut down.

9. A color correction system based on multi-printer consistency, characterized in that, include: The acquisition module is used to acquire the standard color parameters of the reference printhead under standard conditions, the actual color parameters of the target printhead under actual working conditions, the ambient temperature and humidity, and the actual ink viscosity. The compensation judgment module is used to calculate the multidimensional deviation and comprehensive color difference based on the standard color parameters and the actual color parameters, and to judge the color compensation in combination with the constraint conditions. The compensation calculation module is used to calculate the multi-dimensional compensation factor based on the ambient temperature and humidity and the actual ink viscosity, and to calculate the multi-dimensional compensation coefficient in combination with the multi-dimensional deviation. The adjustment module is used to calculate the driving parameters of the target nozzle based on the multidimensional compensation coefficient and the multidimensional compensation factor, and then adjust the working parameters of the target nozzle based on the driving parameters. The calibration calculation module is used to calculate the overall color difference after calibration based on the actual color parameters after calibration. The closed-loop processing module is used to perform graded closed-loop processing based on the calculated corrected comprehensive color difference.

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