An inkjet printing error compensation method, system, device and storage medium

Abstract

The present application relates to the field of inkjet printing technology, and discloses an inkjet printing error compensation method, system, device and storage medium, which calibrates the substrate stage through a laser interferometer and a laser ruler in the whole stroke offline, so as to synchronously obtain the yaw angle error data and the stage position data in the calibration process; generates an error compensation table based on the yaw angle error data and the stage position data; obtains the environmental parameters from the environmental monitoring module, obtains the original position signal of the stage from the laser ruler, corrects the original position signal of the stage based on the environmental parameters to obtain the absolute position signal of the stage; takes the absolute position signal of the stage as the query basis, calls the error compensation table to correct the nozzle coordinate to obtain the nozzle compensation coordinate; generates the nozzle trigger signal based on the nozzle compensation coordinate; the present application offsets the stage yaw and the environmental interference, realizes the differentiated compensation of multiple nozzles, and effectively improves the inkjet printing precision of the large-size substrate.

Description

Technical Field

[0001] This invention relates to the field of inkjet printing technology, and in particular to an inkjet printing error compensation method, system, device and storage medium. Background Technology

[0002] In the field of high-precision large-size inkjet printing, existing technologies are prone to sway angle errors around the rotation axis when the substrate stage moves along the printing axis due to factors such as guide rail tolerance, drive system force ripple, and mechanical vibration. These errors are directly transmitted to the substrate. Existing solutions can only perform static angle correction when the substrate is placed, and cannot dynamically compensate for stage sway and environmental interference during the movement process. This results in a deviation between the printhead trigger position and the actual position of the substrate. The linear offset caused by the amplified sway angle error will seriously damage the printing registration accuracy and cannot meet the requirements of high-precision inkjet printing. Summary of the Invention

[0003] To overcome the shortcomings of the prior art, the present invention aims to provide an inkjet printing error compensation method, system, device and storage medium; the present invention achieves multi-head differential compensation by offsetting stage sway and environmental interference, effectively improving the inkjet printing accuracy of large-size substrates.

[0004] The first aspect of this invention provides an inkjet printing error compensation method applied to an inkjet printing error compensation system. The inkjet printing error compensation system includes: a control device and a substrate stage, a laser interferometer, a laser ruler, and an environmental monitoring module electrically connected to the control device; the inkjet printing error compensation method includes the following steps:

[0005] The substrate stage was calibrated offline throughout its entire stroke using a laser interferometer and a laser ruler, so as to simultaneously acquire yaw angle error data and stage position data during the calibration process.

[0006] An error compensation table is generated based on the yaw angle error data and the platform position data;

[0007] Environmental parameters are obtained from the environmental monitoring module, and the original position signal of the platform is obtained from the laser ruler. The original position signal of the platform is corrected based on the environmental parameters to obtain the absolute position signal of the platform.

[0008] Using the absolute position signal of the platform as the query basis, the error compensation table is called to correct the nozzle coordinates in order to obtain the nozzle compensation coordinates;

[0009] The nozzle trigger signal is generated based on the nozzle compensation coordinates.

[0010] Optionally, in the first implementation manner of the first aspect, the offline calibration of the substrate stage by the laser interferometer and the laser ruler to synchronously obtain the yaw error data and the stage position data during the calibration process comprises: rigidly fixing a mirror of the laser interferometer to the substrate stage, aligning a measurement light path of the laser interferometer to a rotation axis center of the substrate stage, and synchronously transferring the mirror of the laser interferometer with the yaw of the substrate stage; aligning a light path of the laser ruler to a printing axis of the substrate stage, and making the laser ruler coincide with a motion track of the substrate stage; controlling the substrate stage to move at a preset printing speed along the printing axis at a full stroke, and synchronously triggering the laser interferometer to collect the yaw angle during the printing process to obtain the yaw error data and the stage position data.

[0011] Optionally, in the second implementation manner of the first aspect, the generation of the error compensation table based on the yaw error data and the stage position data comprises: associating the yaw error data with the stage position data according to a collection time sequence to form a raw data pair; performing an averaging process on the raw data pair to obtain a discrete error curve; calculating data points on the discrete error curve by using a cubic spline interpolation method to generate a continuous error mapping relationship covering a full stroke of the substrate stage; discretizing the continuous error mapping relationship according to a position interval of the laser ruler measurement accuracy to generate the error compensation table.

[0012] Optionally, in the third implementation manner of the first aspect, the acquisition of the environment parameter from the environment monitoring module, the acquisition of the stage raw position signal from the laser ruler, the correction of the stage raw position signal based on the environment parameter to obtain the stage absolute position signal comprises: acquiring a real-time environment parameter from the environment monitoring module; the environment parameter comprises temperature, air pressure and humidity; acquiring the stage raw position signal from the laser ruler; calculating a real-time air refractive index based on the real-time environment parameter, and correcting the stage raw position signal based on the real-time air refractive index to obtain a corrected position signal; converting the corrected position signal into a pulse signal and accumulating the count to obtain the stage absolute position signal.

[0013] Optionally, in the fourth implementation manner of the first aspect, the correction of the nozzle compensation coordinates based on the stage absolute position signal as a query basis and the error compensation table to obtain the nozzle compensation coordinates comprises: taking the stage absolute position signal as a query address to find a corresponding stage yaw angle from the error compensation table; acquiring the nozzle coordinates from the control device; the nozzle coordinates are horizontal distances of the nozzles relative to the yaw center of the stage; calculating a deviation of the substrate below each nozzle caused by the yaw of the stage based on the yaw angle and the nozzle coordinates; correcting the stage absolute position signal by using the deviation to obtain the nozzle compensation coordinates.

[0014] Optionally, in a fifth implementation form of the first aspect of the present application, the generating the printhead trigger signal based on the nozzle compensation coordinate comprises: obtaining a preset target printing position from the control device; and comparing the nozzle compensation coordinate with the preset target printing position in real time, and generating the printhead trigger signal when the nozzle compensation coordinate is greater than or equal to the preset target printing position.

[0015] The second aspect of the present application provides an inkjet printing error compensation system, comprising a control device and a substrate stage, a laser interferometer, a laser ruler and an environment monitoring module electrically connected to the control device; the control device is used to execute the inkjet printing error compensation method of any one of the above aspects.

[0016] Optionally, in a first implementation form of the second aspect of the present application, the substrate stage is used to carry a glass substrate; the laser interferometer comprises a laser, a first interference mirror group and a first reflecting mirror; the first reflecting mirror is rigidly fixed to the side surface of the substrate stage, the laser, the first interference mirror group and the first reflecting mirror cooperate to form a measurement light path for measuring the yaw angle of the substrate stage around the rotation axis; the laser ruler comprises a bracket, a laser head, a second interference mirror group and a second reflecting mirror, the second reflecting mirror is mounted on the end surface of the substrate stage, the laser head and the second interference mirror group are mounted on the bracket, and the light path of the laser head is parallel to the printing axis of the substrate stage; the laser head, the second interference mirror group and the second reflecting mirror cooperate to collect the original position signal of the stage; the environment monitoring module is used to monitor the temperature, air pressure, humidity and carbon dioxide concentration in real time; the control device comprises a host computer and a master control FPGA, and the host computer and the master control FPGA are electrically connected; the host computer is used to store the error compensation table, the printhead coordinate and the target printing position, and the master control FPGA is used to execute the error compensation calculation and the generation of the printhead trigger signal.

[0017] The third aspect of the present application provides an inkjet printing error compensation device, comprising a memory and at least one processor, the memory stores instructions; at least one processor calls the instructions in the memory, so that the computer device executes the steps of the inkjet printing error compensation method of any one of the above aspects.

[0018] The fourth aspect of the present application provides a computer readable storage medium, the computer readable storage medium stores instructions, the instructions are executed by a processor to realize the steps of the inkjet printing error compensation method of any one of the above aspects.

[0019] In the technical solution of the application, firstly, full-stroke offline calibration is performed by cooperation of a laser interferometer and a laser ruler, and the deflection angle error data and the stage position data are synchronously acquired, thereby providing an accurate error reference covering the full motion range of the stage for subsequent compensation; secondly, an error compensation table is generated based on the calibration data, and the discrete error is converted into a mapping relationship that can be called in real time; then, the environment monitoring module is used to acquire the environmental parameters and correct the original position signal of the laser ruler, thereby eliminating the interference of environmental factors such as temperature and air pressure on the position measurement and ensuring the accuracy of the absolute position signal of the stage; finally, the absolute position signal is used to query the compensation table and correct the nozzle coordinate to obtain the nozzle compensation coordinate, and then a trigger signal is generated based on the coordinate, so that the trigger position of the nozzle can dynamically match the position offset of the substrate caused by the deflection of the stage, effectively offsetting the linear offset caused by the deflection angle error, and finally realizing high-precision inkjet printing and meeting the printing precision requirements of fine patterns on large-size substrates. BRIEF DESCRIPTION OF DRAWINGS

[0020] The above and / or additional aspects and advantages of the present application will become apparent and be readily understood from the following description, taken in conjunction with the following drawings, in which:

[0021] Figure 1 The first flowchart of the inkjet printing error compensation method provided by the embodiment of the present application;

[0022] Figure 2 The second flowchart of the inkjet printing error compensation method provided by the embodiment of the present application;

[0023] Figure 3 The third flowchart of the inkjet printing error compensation method provided by the embodiment of the present application;

[0024] Figure 4 The fourth flowchart of the inkjet printing error compensation method provided by the embodiment of the present application;

[0025] Figure 5 The fifth flowchart of the inkjet printing error compensation method provided by the embodiment of the present application;

[0026] Figure 6 The sixth flowchart of the inkjet printing error compensation method provided by the embodiment of the present application;

[0027] Figure 7 The structure block diagram of the inkjet printing error compensation system provided by the embodiment of the present application;

[0028] Figure 8 The structure schematic diagram of the inkjet printing error compensation device provided by the embodiment of the present application;

[0029] Figure 9 The structure schematic diagram of the inkjet printing error compensation system provided by the embodiment of the present application;

[0030] Figure 10 A structural schematic diagram of a laser interferometer provided for an embodiment of the present application is shown in the figure;

[0031] Figure 11 A structural schematic diagram of a laser ruler provided for an embodiment of the present application is shown in the figure. DETAILED DESCRIPTION

[0032] The present application provides an inkjet printing error compensation method, system, device and storage medium, which accurately solves the printing precision problem caused by the motion platform deflection and environmental interference in the prior art through the complete steps of offline calibration, compensation table generation, environment correction, coordinate compensation and trigger signal generation.

[0033] The terms "first", "second", "third", "fourth" and the like in the description, claims, and drawings of the present application, and those above (if any) are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order. It is to be understood that the use of the terms so termed herein is to be interpreted to allow that they can refer to objects at the same time where appropriate and applicable. It will be further understood that the data used herein can be interchanged, where appropriate and applicable, to refer to any of the embodiments described herein, unless otherwise indicated hereinabove or hereinbelow. Furthermore, the terms "comprising", "having", "including", and the like, are to be construed to be open-ended, for example, to mean including but not limited to, for example, a process, method, system, product, or apparatus that comprises a list of steps or units as opposed to only those steps or units that are expressly listed. Additionally, the term "comprising" or "including" and any of their derivatives, is intended to cover the non-exclusive inclusion of the steps or units so that the process, method, system, product, or apparatus is not limited to those steps or units that are clearly listed, but can include other steps or units that are not clearly listed or inherent to such process, method, system, product, or apparatus.

[0034] For the sake of understanding, the specific flow of the embodiments of the present application is described below, please refer to Figure 1 An embodiment of the inkjet printing error compensation method in the embodiments of the present application comprises:

[0035] The inkjet printing error compensation system comprises a control device, a substrate carrier, a laser interferometer, a laser ruler and an environment monitoring module electrically connected with the control device;

[0036] The substrate carrier is used for carrying a glass substrate and moving at a preset printing speed along the printing axis (Y axis) under the driving of a linear motor. The vacuum adsorption assembly tightly fixes the substrate to the table top through negative pressure to avoid relative displacement of the substrate and the carrier during movement, and to ensure that the carrier deflection can be completely transmitted to the substrate. The substrate carrier and the main control FPGA of the control device are electrically connected through a servo driver to receive the motion control signal output by the main control FPGA. The substrate carrier side is provided with a positioning pin hole for fixing the first mirror of the laser interferometer. The end face of the substrate carrier is fixed with the second mirror of the laser ruler through bolts.

[0037] The laser interferometer selects a common dual-frequency laser interferometer, including a laser, a first interference mirror group and a first mirror; the back of the first mirror is provided with a positioning pin matched with a positioning pin hole of the substrate stage, and the positioning pin is rigidly fixed with the substrate stage; the laser interferometer is used for measuring the deflection angle error of the substrate stage around the rotation axis (Z axis) in the offline calibration stage, the laser and the first interference mirror group are fixed on an independent base to ensure that there is no vibration interference in the measurement process, the rotation center of the substrate stage around the Z axis is aligned through the light path to realize high-precision measurement of the deflection angle; the laser is electrically connected with the host computer of the control device for uploading the deflection angle error data collected in the offline calibration process;

[0038] The laser ruler selects a long-axis high-precision position feedback laser ruler, including a bracket, a laser head, a second interference mirror group and a second mirror; the laser ruler is used for real-time acquisition of the original position signal of the substrate stage, the light path of the laser head is parallel to the printing axis (Y axis) of the stage and completely coincides with the motion track of the stage; the laser head is electrically connected with the main control FPGA of the control device through the SPI interface, and the original position pulse signal of the stage is output in real time;

[0039] The environmental monitoring module adopts a multi-parameter environmental sensor, including a temperature sensor, an air pressure sensor, a humidity sensor and a carbon dioxide sensor; the environmental monitoring module is used for real-time monitoring of the temperature, air pressure, humidity and carbon dioxide concentration of the printing environment, providing data support for the environmental correction of the original position signal of the laser ruler, and eliminating the influence of air refractive index change on the laser wavelength; the environmental monitoring module is electrically connected with the main control FPGA of the control device;

[0040] The control device includes a host computer and a main control FPGA, and the host computer is electrically connected with the main control FPGA; the host computer is used for storing the error compensation table generated by offline calibration, the preset nozzle X axis position parameter and the printing target position data; the main control FPGA is used for receiving data from each module, calculating the air refractive index, correcting the position signal, querying the compensation table, calculating the nozzle compensation coordinates and generating the nozzle trigger signal.

[0041] The inkjet printing error compensation system realizes accurate offset of the motion deflection of the substrate stage and environmental interference through the cooperative work of each entity module, and the specific process is as follows:

[0042] The control device first issues a motion instruction to the substrate stage to drive the stage to complete the full stroke motion along the printing axis at a preset printing speed; the laser interferometer and the laser ruler are triggered simultaneously, the laser interferometer captures the deflection angle error data of the stage around the rotation axis through the mirror rigidly connected with the stage, and the laser ruler collects real-time position data of the stage along the printing axis; the control device receives and stores the two sets of synchronous data, accumulates multiple sets of full stroke data through multiple repeated motions and data collection to eliminate random interference, and establishes an error reference for subsequent compensation;

[0043] The control device pre-processes a plurality of sets of off-line collected yaw angle error data and stage position data, takes the average after eliminating abnormal data, and obtains a discrete "position-yaw angle" mapping relationship; then an interpolation algorithm is used to convert the discrete data into a continuous error function covering the full stroke of the stage, and the continuous function is discretized into a "stage position-error compensation amount" key-value pair according to the measurement accuracy of the laser ruler to form an error compensation table and store it, providing a callable error mapping basis for online compensation;

[0044] Subsequently, when real-time printing is performed, the environmental monitoring module continuously collects environmental parameters (temperature, air pressure, humidity, etc.) and transmits them to the control device; the control device calculates the real-time air refractive index according to the environmental parameters, corrects the original position signal output by the laser ruler based on the refractive index, and eliminates the influence of the wavelength shift of the laser caused by environmental factors on the position measurement; the corrected position signal is accumulated by the position counting unit to generate an accurate stage absolute position signal;

[0045] Finally, the control device calls the corresponding error compensation amount from the error compensation table with the stage absolute position signal as the query address; combined with the preset position parameters of each nozzle, the position correction value of each nozzle caused by the yaw of the stage is calculated, and then the nozzle compensation coordinates of each nozzle are obtained; the nozzle compensation coordinates are compared with the preset printing target position in real time, and when the compensation coordinates reach the target position, the nozzle trigger signal is immediately generated and output to control the nozzle to complete inkjet at the corresponding target position of the substrate, realizing dynamic offset of the yaw error.

[0046] The inkjet printing error compensation method comprises the following steps:

[0047] 101. Off-line calibration of the substrate stage by a laser interferometer and a laser ruler to synchronously obtain yaw angle error data and stage position data during the calibration process;

[0048] In this embodiment, the mirror of the laser interferometer is first rigidly connected with the substrate stage to ensure that the yaw of the stage can be synchronously transmitted to the mirror, and the optical path of the laser ruler is adjusted to be parallel to the printing axis of the stage, so that the measurement trajectory of the laser ruler is attached to the movement trajectory of the stage; then the stage is controlled to complete the full stroke movement at a preset printing speed, and the laser interferometer is triggered to collect the yaw angle error data of the stage in real time during the movement process, and the stage position data output by the laser ruler is synchronously obtained, and the movement and collection process is repeated multiple times to eliminate random interference, and finally the yaw angle error data and the stage position data covering the full stroke of the stage are obtained.

[0049] 102. Generating an error compensation table based on the yaw angle error data and the stage position data;

[0050] In this embodiment, first, the yaw angle error data is associated with the stage position data according to the collection time sequence to form a "position-yaw angle" original data pair; then, the original data pair is preprocessed, and after removing the outliers, the average value is taken to obtain a discrete error curve; then, the discrete error curve is converted into a continuous error mapping relationship covering the full stroke of the stage through a cubic spline interpolation method; finally, the position interval is set according to the measurement accuracy of the laser ruler, the continuous mapping relationship is discretized into a "position node-yaw angle error" key-value pair, and an error compensation table is generated.

[0051] 103. Obtain the environmental parameters from the environmental monitoring module, obtain the stage original position signal from the laser ruler, and correct the stage original position signal based on the environmental parameters to obtain the stage absolute position signal;

[0052] In this embodiment, first, the temperature, air pressure and humidity parameters of the printing environment are collected in real time through the environmental monitoring module; at the same time, the original position signal of the stage movement is obtained from the laser ruler; the real-time air refractive index is calculated based on the collected environmental parameters, and the original position signal of the laser ruler is corrected according to the change of the refractive index to eliminate the measurement deviation caused by environmental factors; finally, the corrected position signal is pulse accumulated and counted to obtain the stage absolute position signal which can truly reflect the actual movement position of the stage.

[0053] 104. Take the stage absolute position signal as the query basis, call the error compensation table to correct the nozzle coordinates to obtain the nozzle compensation coordinates;

[0054] In this embodiment, first, the stage absolute position signal is taken as the query address to call the stage yaw angle of the corresponding position from the error compensation table; then, the preset transverse coordinates of each nozzle relative to the yaw center of the stage are read from the control device; the Y-axis direction offset of the substrate under each nozzle caused by the yaw of the stage is calculated by combining the yaw angle and the nozzle coordinates; the stage absolute position signal is corrected by using the offset to obtain the nozzle compensation coordinates of each nozzle which can offset the influence of yaw.

[0055] 105. Generate the nozzle trigger signal based on the nozzle compensation coordinates;

[0056] In this embodiment, first, the preset target printing positions of each nozzle on the substrate are obtained from the control device; the nozzle compensation coordinates of each nozzle are compared with the corresponding target printing positions in real time by using a parallel processing method; when it is detected that the nozzle compensation coordinates are greater than or equal to the target printing positions, a high-level nozzle trigger signal is immediately generated to control the nozzle to accurately eject ink droplets at the target position on the substrate.

[0057] In the embodiment of the present application, firstly, full stroke offline calibration is performed by cooperating the laser interferometer with the laser ruler, and the deflection angle error data and the stage position data are synchronously obtained, so as to provide accurate error reference covering the full motion range of the stage for subsequent compensation; secondly, the error compensation table is generated based on the calibration data, so as to convert the discrete error into a mapping relationship which can be called in real time; thirdly, the environmental monitoring module is used to obtain the environmental parameters and correct the original position signal of the laser ruler, so as to eliminate the interference of environmental factors such as temperature and air pressure on the position measurement, and ensure the accuracy of the absolute position signal of the stage; finally, the compensation table is queried based on the absolute position signal, and the nozzle compensation coordinates are obtained by correcting the jet head coordinates, and then the trigger signal is generated based on the coordinates, so that the jet head trigger position can dynamically match the position offset of the substrate caused by the deflection of the stage, the linear offset caused by the deflection angle error can be effectively offset, and finally the high-precision inkjet printing is realized, and the printing precision requirement of the fine pattern of the large-size substrate is met.

[0058] Please refer to Figure 2 In the embodiment of the present application, two embodiments of the inkjet printing error compensation method include:

[0059] 201, rigidly fixing the mirror of the laser interferometer on the substrate stage, and aligning the measurement light path of the laser interferometer with the center of the rotation axis of the substrate stage, so that the mirror of the laser interferometer and the deflection of the substrate stage are synchronously transmitted;

[0060] In the embodiment, the mirror of the laser interferometer is first rigidly connected with the side surface of the substrate stage, so that when the stage deflection around the rotation axis (Z axis), the mirror can move synchronously with the stage without relative displacement, so that the deflection state is completely transmitted to the mirror; then the position of the laser of the laser interferometer and the first mirror group is adjusted, so that the measurement light paths of the two are accurately aligned with the rotation center of the substrate stage around the Z axis, so as to ensure that the deflection angle measured by the interferometer is the true deflection error of the whole stage, rather than the local position offset;

[0061] The rigid connection of the mirror and the stage makes the mirror can synchronously respond to the deflection of the stage, that is, the slight deflection of the stage around the Z axis will completely drive the mirror to synchronously deflect, so as to ensure that the measured deflection angle is consistent with the actual deviation; and the light path is aligned with the rotation center, because the deflection of the stage is based on the center, only when the measurement reference and the deflection reference are consistent, the system error introduced by the reference misalignment can be avoided.

[0062] 202, aligning the laser ruler light path with the printing axis of the substrate stage, so that the motion trajectory of the laser ruler and the substrate stage is coincident;

[0063] In the embodiment, the mirror is installed on the end surface of the substrate stage, and the reading head is arranged at a fixed position matched with the motion direction of the stage, the relative position of the two is adjusted, so that the measurement light path of the laser ruler is parallel to the printing axis (Y axis) of the substrate stage, and finally the measurement trajectory of the laser ruler is coincident with the motion trajectory of the stage along the printing axis.

[0064] In principle, the laser ruler light path is parallel to the printing axis, and the measurement trajectory coincides with the motion trajectory of the stage, which is the core to ensure the accuracy of position measurement. Only when the measurement direction is consistent with the motion direction of the stage, the position data collected by the laser ruler can truly reflect the actual displacement of the stage along the printing axis, avoid the position measurement deviation caused by the light path deviation, and make the laser ruler output the position signal synchronized with the motion of the stage, providing an accurate position reference for the subsequent correspondence of the "yaw angle-position" data.

[0065] 203、Control the stage substrate to move uniformly along the printing axis at a preset printing speed for the full stroke, and during the printing process, trigger the laser interferometer to collect the yaw angle based on the position pulse of the laser ruler as the trigger source, to obtain the yaw angle error data and the stage position data;

[0066] In this embodiment, the control device drives the substrate stage to move uniformly along the printing axis at a preset printing speed for the full stroke, ensuring that the motion state is consistent with the speed and stroke during actual printing. During the motion process, the position pulse output by the laser ruler is used as the synchronous trigger signal. Each time a position pulse is generated, the laser interferometer immediately collects the yaw angle data corresponding to the position, thereby realizing the synchronous acquisition of the stage position data and the yaw angle error data, and finally obtaining two sets of synchronous data covering the full stroke of the stage;

[0067] In principle, the motion of the stage simulates the actual printing conditions, because the yaw of the stage is significantly affected by the motion speed (such as the difference in force ripple of the driving system at different speeds, which will cause different yaw angles). Only when it is consistent with the actual printing conditions, the collected yaw angle data has actual compensation significance. Using the position pulse of the laser ruler as the trigger source can ensure that each position data corresponds to a unique yaw angle data, avoiding data mismatch caused by asynchronous collection. The collected data can truly reflect the dynamic yaw characteristics of the stage motion, and has strong synchronization, providing high-quality data support for generating accurate error compensation table, and effectively eliminating the influence of random interference and working condition difference on the calibration result.

[0068] Please refer to Figure 3 The three embodiments of the inkjet printing error compensation method in the embodiment of the application include:

[0069] 301、Correlate the yaw angle error data and the stage position data according to the collection time sequence to form an original data pair;

[0070] In this embodiment, in step 203, the laser interferometer is triggered to collect the yaw angle by the laser ruler position pulse, and each position pulse corresponds to one yaw angle collection. Both have the same timestamp mark. The control device directly binds the stage position data and the yaw angle error data collected at the same time according to the timestamp, forms the original data pair of “stage position-yaw angle error”, and sorts and stores the original data pair according to the stage movement direction (from the printing starting point to the ending point). The same timestamp means that the data corresponds to the same movement position of the stage, which can avoid the mismatch of position and yaw angle from the root, and ensure the physical meaning consistency of the original data pair.

[0071] 302, average the original data pairs to obtain a discrete error curve;

[0072] In this embodiment, first, abnormal data of each group of original data is removed (for example, if the yaw angle error of a position exceeds the mean value of multiple groups of data at the position by ±3 times the standard deviation, it is determined to be an abnormal value caused by sudden interference and is removed); then, for each same position point in the full travel of the stage, the arithmetic mean value of the yaw angle error in the remaining valid original data pairs is calculated, and the “position point-error mean value” is taken as a new discrete data point; finally, all discrete data points are connected in turn according to the movement direction of the stage to form a discrete error curve covering the full travel;

[0073] Among the original data pairs collected multiple times, there are errors caused by random interference, and through arithmetic averaging, positive and negative errors can be offset, and the systematic error of the stage yaw is retained. Removing abnormal values is to avoid the influence of extreme interference (such as instantaneous strong vibration) on the average value, effectively filter random noise, make the discrete error curve closer to the actual yaw rule of the stage movement, and ensure that the discrete error curve can truly reflect the inherent yaw characteristics of the stage. The credibility of the discrete data points after averaging is significantly improved, providing a more accurate discrete reference for subsequent interpolation calculation.

[0074] 303, calculate the data points on the discrete error curve using the cubic spline interpolation method to generate a continuous error mapping relationship covering the full travel of the substrate stage;

[0075] In this embodiment, based on the discrete error curve, the discrete data points are taken as interpolation nodes and substituted into the cubic spline interpolation algorithm. By constructing a segmented cubic polynomial function, the error change between the adjacent two interpolation nodes conforms to the cubic function rule, and the first derivative and the second derivative of the adjacent segmented function at the node are continuous. Through this algorithm, the yaw angle error values of all “uncollected discrete points” in the full travel of the stage (from the printing starting point to the ending point) are calculated, and finally a continuous mapping relationship of “position-yaw angle error” covering the full travel of the substrate stage is formed (that is, for any input stage position Y, the corresponding yaw angle error θ can be obtained through the continuous mapping relationship);

[0076] Cubic spline interpolation was chosen over other interpolation methods (such as linear interpolation) because it ensures the smoothness of the error curve. The stage runout is caused by inherent factors such as guide rail tolerance and mechanical rigidity, and its error change is continuous and gradual. The smooth curve of cubic spline interpolation can more realistically simulate this continuous change. At the same time, the higher-order derivatives of cubic spline interpolation at the nodes are continuous, which ensures that the results have good continuity and accuracy when querying the error at any position. By performing cubic spline interpolation, the "error gap" between discrete data points is filled, so that a more accurate runout angle error value can be obtained at any position within the entire stroke of the stage.

[0077] 304. Set the position interval according to the measurement accuracy of the laser ruler, and discretize the continuous error mapping relationship to generate an error compensation table;

[0078] In this embodiment, the interval is set based on the measurement accuracy of the laser ruler. This interval is consistent with the accuracy of the position signal acquired by the laser ruler, ensuring that the position resolution of the compensation table can match the real-time position measurement accuracy of the laser ruler. Then, based on the continuous error mapping relationship, the yaw angle error value corresponding to each position node is queried, and the "position-yaw angle error value" is stored as a key-value pair. Finally, all key-value pairs are arranged in ascending order of position nodes to generate an error compensation table, which is then stored in the control device for quick retrieval during subsequent online compensation.

[0079] Setting the position interval based on the laser ruler's measurement accuracy is to ensure that the compensation accuracy matches the position measurement accuracy. If the compensation table interval is greater than the laser ruler's accuracy, the corresponding compensation value cannot be found for some fine positions measured by the laser ruler, requiring additional interpolation calculations (reducing efficiency). If the interval is less than the laser ruler's accuracy, the compensation table data will be redundant (increasing storage burden and query time).

[0080] The position resolution of the error compensation table is perfectly matched with the measurement accuracy of the laser ruler, ensuring the accuracy of online compensation and avoiding data redundancy. This allows the control device to quickly and accurately query the corresponding compensation value during real-time printing, meeting the high requirements of inkjet printing for the real-time performance of trigger signals (such as rapid response even when 50 printheads are compensated in parallel).

[0081] Please see Figure 4 The four embodiments of the inkjet printing error compensation method in this invention include:

[0082] 401. Obtain real-time environmental parameters from the environmental monitoring module; the environmental parameters include temperature, air pressure, and humidity;

[0083] In this embodiment, the control device establishes a real-time data transmission link with the environment monitoring module, and the environment monitoring module continuously collects temperature, air pressure and humidity parameters in the printing environment at a preset sampling frequency (e.g., 1 Hz). The collected parameters are transmitted in real time to the environment compensation module of the control device through a data interface. The environment compensation module performs validity check on the received parameters (e.g., judges whether the parameters are within a reasonable range, and eliminates abnormal values), to ensure that the environmental parameters input for subsequent correction calculation are real and reliable. Temperature, air pressure and humidity are the core factors affecting the air refractive index. The air refractive index decreases with the increase of temperature, increases with the increase of air pressure, and decreases with the increase of humidity. The laser ruler measures displacement based on the wavelength of laser. Changes in the air refractive index will directly cause the actual wavelength of laser to shift, thereby introducing position measurement errors. Therefore, real-time acquisition of these three types of parameters is a prerequisite for subsequent error correction.

[0084] 402. Obtain the original position signal of the stage from the laser ruler;

[0085] In this embodiment, the reading head of the laser ruler works in cooperation with the mirror installed on the end face of the substrate stage. The reading head continuously emits a laser beam, which is reflected by the mirror and returned to the reading head. The reading head converts the displacement of the stage into discrete position pulse signals by detecting the change of the interference signal of the laser beam. The pulse signal serves as the original position signal of the stage, which is transmitted in real time to the position counter module of the control device. The module performs preliminary filtering on the original signal to ensure that the signal is free from interference, and records the transmission timing of the pulse signal to provide ordered original data for subsequent cumulative counting. The laser ruler measures displacement based on the principle of laser interference. The frequency of the pulse signal output by the laser ruler is positively correlated with the motion speed of the stage, and the total number of pulses is positively correlated with the total displacement of the stage. The original position signal directly reflects the initial measurement result of the laser ruler on the displacement of the stage.

[0086] 403. Calculate the real-time air refractive index based on the real-time environmental parameters, and correct the original position signal of the stage based on the real-time air refractive index to obtain a corrected position signal;

[0087] In this embodiment, the real-time air refractive index in the current environment is calculated based on the obtained real-time temperature t, air pressure P and relative humidity H, combined with the optimized Edlen dispersion formula. The specific process is as follows:

[0088] First, calculate the relative refractive index of air in the standard state :

[0089] ;

[0090] In the formula, is the wave number of light in vacuum, , which is the wavelength of laser in vacuum;

[0091] Then, the relative refractive index when the carbon dioxide concentration x content deviates from 400ppm is calculated :

[0092] ;

[0093] Subsequently, based on the real-time collected air pressure P and temperature t, the relative refractive index of standard dry air in the real-time measured environment is calculated :

[0094] ;

[0095] Then, the relative humidity H is converted into water vapor partial pressure f, and the real-time air refractive index is calculated based on the water vapor partial pressure f :

[0096] ;

[0097] In the formula, ;

[0098] The increase in temperature will reduce the air refractive index, the increase in air pressure will increase the air refractive index, and the increase in humidity (water vapor partial pressure) will reduce the air refractive index. Through the above formula, the influence of multiple environmental parameters can be integrated to calculate the real-time air refractive index in the current environment ;

[0099] Since the laser ruler measures the displacement of the platform by the wavelength of the laser, and the change in air refractive index will cause the actual wavelength of the laser to deviate from the standard wavelength, thereby causing the original displacement value measured by the laser ruler to deviate from the actual displacement of the platform; therefore, according to the ratio relationship between the real-time air refractive index and the standard air refractive index ( ), the original position signal corresponding to the displacement value output by the laser ruler is adjusted, the original displacement value disturbed by the environment is corrected to the displacement value conforming to the actual movement of the platform, and finally the corrected position signal is obtained:

[0100] ;

[0101] In the formula, is the corrected position signal, is the original position signal;

[0102] The displacement measurement accuracy of the laser ruler depends on the stability of the laser wavelength, and air is the medium for laser propagation. Changes in environmental parameters will change the medium characteristics (air refractive index), causing the wavelength to shift when the laser actually propagates. If the original position signal is directly used, measurement errors will be introduced. By real-time calculation of the air refractive index and reverse correction of the original signal, the essence is to offset the influence of changes in medium characteristics on the laser wavelength, and restore the accuracy of displacement measurement.

[0103] 404. converting the corrected position signal into a pulse signal and accumulating the count to obtain a stage absolute position signal;

[0104] In this embodiment, the position counter module of the control device first converts the corrected position signal into a digital pulse recognizable by the counter through signal format conversion; then starts the counter, takes the rising edge of the laser ruler pulse signal as the counting trigger edge, and accumulates the count of the converted digital pulse (the initial value of the count is set as the pulse number corresponding to the printing start position of the stage, such as 0 pulse corresponding to Y=0 mm); then, the absolute position signal of the stage in real time is calculated according to the calculation formula “absolute position=counting initial value corresponding displacement+accumulated pulse number x single pulse corresponding displacement”, and the signal is transmitted to the control device in real time for subsequent compensation calculation; the pulse signal output by the laser ruler is discrete and can only reflect the relative displacement change of the stage, while the accumulated count can convert the discrete relative displacement into continuous absolute displacement from the “printing start point”, i.e. the absolute position signal, which can reflect the specific position of the stage in the full stroke.

[0105] Please refer to Figure 5 The five embodiments of the inkjet printing error compensation method in the embodiment of the application include:

[0106] 501. taking the stage absolute position signal as a query address to find the stage yaw angle corresponding to the position in the error compensation table;

[0107] In this embodiment, the control device receives the stage absolute position signal, takes the absolute position as a query address, and accesses the error compensation table stored in the control device; if the absolute position signal completely matches the preset position node in the compensation table, the stage yaw angle corresponding to the node is directly read; if there is a slight deviation, the yaw angle corresponding to the current absolute position is calculated through a linear interpolation algorithm, so as to ensure that the query result can cover any position in the full stroke of the stage; the error compensation table is a “position-yaw angle” mapping relationship generated based on “offline calibration+interpolation processing”, and the resolution of the position node is consistent with the measurement accuracy of the laser ruler, while the stage absolute position signal is a precise position after environmental correction, and the matching query of the two is essentially to correspond “real-time position” and “prestored error law”, and quickly obtain the inherent yaw characteristics of the stage at the current position.

[0108] 502. obtaining a printhead coordinate from the control device; the printhead coordinate is a horizontal distance of the printhead relative to the yaw center of the stage;

[0109] In the embodiment, the nozzle coordinates (i.e. the X-axis transverse distance of the nozzle relative to the center of the deflection of the carrier) are preset in the system initialization stage and stored in the upper computer of the control device; the nozzle coordinates are determined based on the previous equipment debugging, and the deflection center of the substrate carrier around the Z-axis is taken as the X-axis origin (which can be determined by the laser interferometer), the distance of each nozzle from the origin in the X-axis direction is measured, and the distance values are taken as the nozzle coordinates; when the carrier is deflected, the points at different X-axis positions on the substrate will produce different Y-axis direction offsets (the farther from the deflection center, the greater the offset), and the nozzle coordinates directly reflect the transverse distance of the nozzle from the deflection center, which is the core variable for calculating the offset of the substrate below the nozzle. Only by obtaining this parameter can the differentiated compensation for each nozzle be realized.

[0110] 503. Calculate the offset of the substrate below each nozzle due to the deflection of the carrier based on the deflection angle and the nozzle coordinates;

[0111] In the embodiment, the control device calls the carrier deflection angle obtained in step 501 and the corresponding nozzle coordinates obtained in step 502 one by one according to the nozzle number, and calculates the offset based on the geometric deflection principle; since the carrier is deflected around the Z-axis, the substrate below the nozzle will be deflected synchronously with the carrier, forming a geometric relationship with the deflection center as the vertex and the nozzle coordinates as the transverse distance; the farther the nozzle is from the deflection center, the greater the offset of the substrate below it in the Y-axis direction; combined with the size of the current deflection angle of the carrier and the transverse distance of the nozzle from the deflection center, the specific offset of the substrate below each nozzle in the Y-axis direction can be calculated, ensuring that the quantified data matched with the offset of the substrate below the nozzle can be obtained for the nozzles at different positions; the deflection of the carrier belongs to rigid body rotation, and the Y-axis offset of any point on the substrate is positively correlated with the transverse distance of the point from the deflection center and the deflection angle of the carrier. By combining the two to calculate the offset, the correlation can be accurately quantified, and errors caused by ignoring the differences in nozzle positions can be avoided;

[0112] The compensation method of the present application can independently calculate the offset for each nozzle, accurately match the actual offset of the substrate below different nozzles (such as the offset of the nozzle at the edge of a large-size substrate being significantly larger than that of the nozzle at the center), and greatly improve the differentiated accuracy of multi-nozzle compensation compared with the scheme of uniform compensation for all nozzles in the prior art, which is more suitable for the high-precision printing needs of large-size substrates.

[0113] 504. Modify the absolute position signal of the carrier using the offset to obtain the nozzle compensation coordinates;

[0114] In this embodiment, the stage absolute position signal obtained in step 404 is operated with the offset calculated in step 503. Since the substrate above the stage has been offset due to the deflection when the stage actually moves to the absolute position, the target printing position on the substrate does not coincide with the absolute position of the stage, so the absolute position of the stage needs to be subtracted by the offset of the substrate below the nozzle to obtain the nozzle compensation coordinate. The nozzle compensation coordinate is essentially the "equivalent trigger position of the stage", which means that even if the actual position of the stage does not change, the compensation coordinate obtained by correction can make the trigger timing of the nozzle accurately match the target printing position of the substrate, offsetting the position misalignment caused by the deflection; in principle, the absolute position of the stage reflects the physical position of the stage itself, while the nozzle compensation coordinate reflects the "equivalent position of the stage corresponding to the target printing position of the substrate". Since the target printing position is offset relative to the stage due to the deflection of the substrate, the position of the stage can be corrected to the equivalent position matching the target position of the substrate by subtracting the offset, which fundamentally eliminates the misalignment of the stage position and the substrate position caused by the deflection, and ensures that the ink droplets can accurately fall on the target area of the substrate.

[0115] Please refer to Figure 6 The six embodiments of the inkjet printing error compensation method in the embodiments of the present application include:

[0116] 601. Obtain a preset target printing position from a control device;

[0117] In this embodiment, the preset target printing position is generated based on the printing pattern design file of the substrate. Before the printing task is started, the pattern design file is parsed by the upper computer software to extract the Y-axis target position (i.e. the target printing position) of each nozzle that needs to eject ink droplets. The target printing position is the theoretical coordinate of the substrate pattern design, which is the core reference for determining whether the nozzle needs to be triggered. Only when the target position of each nozzle is clear, can the trigger timing be determined by comparing with the nozzle compensation coordinate, and the ink droplets can be ensured to fall within the designed pattern area instead of the misaligned position after the deflection of the stage.

[0118] 602. Real-time comparison between the nozzle compensation coordinate and the preset target printing position, and when the nozzle compensation coordinate is greater than or equal to the preset target printing position, a nozzle trigger signal is generated;

[0119] In this embodiment, the trigger module of the control device adopts a parallel processing architecture, and independent logic units (for example, 50 logic units corresponding to 50 nozzles) consistent with the number of nozzles are established, each logic unit is only responsible for the comparison and trigger signal generation of one nozzle, and each logic unit synchronously presets a target printing position and a nozzle compensation coordinate, and the two are compared in real time through a hardware logic circuit; when it is detected that the nozzle compensation coordinate is greater than or equal to the preset target printing position, the logic unit immediately generates a high-level trigger pulse, which is a nozzle trigger signal, and the trigger signal is transmitted to the driver of the corresponding nozzle, and the driver controls the nozzle to immediately eject ink droplets after receiving the signal;

[0120] The nozzle compensation coordinate is an equivalent trigger position after the compensation of the stage deflection, and when the coordinate reaches the target printing position, it means that the target area on the substrate has moved to the position directly below the nozzle (although the actual position of the stage is different from the target position due to the deflection, the compensation coordinate has corrected the deviation), and the trigger of the nozzle can ensure that the ink droplets are accurately landed on the target area;

[0121] The parallel processing architecture is adopted because multiple nozzles need to be compared and triggered at the same time to avoid trigger delay caused by serial processing (for example, serial processing of 50 nozzles will cause microsecond-level delay, resulting in misplacement of ink droplets of edge nozzles); the parallel processing architecture based on the master control FPGA can ensure that the trigger judgment of all nozzles is completed synchronously without delay difference, which meets the needs of simultaneous printing of multiple nozzles on a large-size substrate, controls the total delay from the generation of the trigger signal to the response of the nozzle to be in the order of hundreds of nanoseconds, matches the trigger timing requirement under high-speed movement of the stage, and finally realizes high-precision positioning of ink droplets in the whole substrate range.

[0122] The above describes the inkjet printing error compensation method in the embodiment of the application, and the following describes the inkjet printing error compensation system in the embodiment of the application, please refer to Figure 7 、 Figures 9 to 11 , an embodiment of the inkjet printing error compensation system in the embodiment of the application includes:

[0123] The inkjet printing error compensation system includes a control device 701, a substrate stage 702, a laser interferometer 703, a laser ruler 704, and an environment monitoring module 705 electrically connected with the control device 701;

[0124] The substrate stage 702 is used to carry a glass substrate;

[0125] The laser interferometer 703 includes a laser 7031, a first interference mirror group 7032, and a first reflecting mirror 7033; the first reflecting mirror 7033 is rigidly fixed to the side surface of the substrate stage 702, the laser 7031, the first interference mirror group 7032, and the first reflecting mirror 7033 cooperate to form a measurement light path for measuring the deflection angle of the substrate stage 702 around the rotation axis.

[0126] The laser ruler 704 comprises a support 7042, a laser head 7041, a second interference mirror group 7044 and a second reflecting mirror 7043, the second reflecting mirror 7043 is installed on the end face of the substrate stage, the laser head 7041 and the second interference mirror group 7044 are installed on the support 7042, and the optical path of the laser head 7041 is parallel to the printing axis of the substrate stage 702; the laser head 7041, the second interference mirror group 7044 and the second reflecting mirror 7043 cooperate to collect the original position signal of the stage;

[0127] The environmental monitoring module 705 is used for monitoring the temperature, air pressure, humidity and carbon dioxide concentration in real time;

[0128] The control device 701 comprises a host computer and a master control FPGA, the host computer and the master control FPGA are electrically connected; the host computer is used for storing the error compensation table, the nozzle coordinates and the target printing position, and the master control FPGA is used for performing error compensation calculation and nozzle trigger signal generation.

[0129] Figure 8 is a structural schematic diagram of an inkjet printing error compensation device provided by an embodiment of the present application. The inkjet printing error compensation device 900 can have relatively large differences due to different configurations or performances, and can include one or more central processing units (CPUs) 910 (for example, one or more processors) and a memory 920, and one or more storage media 930 (for example, one or more mass storage devices) storing application programs 933 or data 932. The memory 920 and the storage media 930 can be temporary storage or persistent storage. The programs stored in the storage media 930 can include one or more modules (not shown in the figure), and each module can include a series of instruction operations in the inkjet printing error compensation device 900. Furthermore, the processor 910 can be configured to communicate with the storage media 930 and execute a series of instruction operations in the storage media 930 on the inkjet printing error compensation device 900 to implement the steps of the inkjet printing error compensation method provided by each method embodiment described above.

[0130] The inkjet printing error compensation device 900 can also include one or more power supplies 940, one or more wired or wireless network interfaces 950, one or more input / output interfaces 960, and / or one or more operating systems 931, such as Windows Serve, Mac OS X, Unix, Linux, FreeBSD, etc. Those skilled in the art can understand that, Figure 9The illustrated inkjet print error compensation device structure does not constitute a limitation on inkjet print error compensation devices, which can include more or fewer components than illustrated, or combine certain components, or have a different arrangement of components.

[0131] The present application also provides a computer readable storage medium, which can be a non-volatile computer readable storage medium, or a volatile computer readable storage medium, and the computer readable storage medium stores instructions, which, when executed on a computer, cause the computer to perform the steps of the inkjet print error compensation method.

[0132] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working process of the above-described system or device, unit can refer to the corresponding process in the foregoing method embodiments, which will not be described here.

[0133] The integrated unit, if implemented in the form of a software functional unit and sold or used as an independent product, can be stored in a computer readable storage medium. Based on such understanding, the technical solutions of the present application essentially or the part that contributes to the prior art, or the whole or part of the technical solutions can be embodied in the form of a software product. The computer software product is stored in a storage medium, and includes a number of instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present application. The foregoing storage medium includes: a U disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, and various program code storage media.

[0134] Finally, it should be noted that: the above only describes the preferred examples of the present application, and does not limit the present application, although the present application has been described in detail with reference to the foregoing embodiments, and for those skilled in the art, the technical solutions recorded in the foregoing embodiments can still be modified, or some technical features can be replaced. Any modification, equivalent replacement, improvement, etc. within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A method for compensating inkjet printing errors, characterized in that, An inkjet printing error compensation system is applied, comprising: a control device and a substrate stage, a laser interferometer, a laser ruler, and an environmental monitoring module electrically connected to the control device; the inkjet printing error compensation method includes the following steps: The substrate stage was calibrated offline throughout its entire stroke using a laser interferometer and a laser ruler, so as to simultaneously acquire yaw angle error data and stage position data during the calibration process. An error compensation table is generated based on yaw angle error data and stage position data. This generation includes: associating yaw angle error data and stage position data according to the acquisition sequence to form raw data pairs; averaging the raw data pairs to obtain discrete error curves; calculating the data points on the discrete error curves using cubic spline interpolation to generate a continuous error mapping relationship covering the entire stroke of the stage; and discretizing the continuous error mapping relationship by setting position intervals according to the laser ruler measurement accuracy to generate the error compensation table. Environmental parameters are obtained from the environmental monitoring module, and the original position signal of the platform is obtained from the laser ruler. The original position signal of the platform is corrected based on the environmental parameters to obtain the absolute position signal of the platform. Using the absolute position signal of the platform as the query basis, the error compensation table is called to correct the nozzle coordinates in order to obtain the nozzle compensation coordinates; The nozzle trigger signal is generated based on the nozzle compensation coordinates.

2. The inkjet printing error compensation method according to claim 1, characterized in that, The offline calibration of the substrate stage using a laser interferometer and laser ruler to simultaneously acquire yaw angle error data and stage position data during the calibration process includes: The mirror of the laser interferometer is rigidly fixed to the substrate stage, and the measurement optical path of the laser interferometer is aligned with the center of the rotation axis of the substrate stage, so that the mirror of the laser interferometer and the deflection of the substrate stage are transmitted synchronously. Align the laser ruler's optical path with the printing axis of the substrate stage, so that the movement trajectories of the laser ruler and the substrate stage coincide. The control substrate stage moves at a constant speed along the printing axis throughout its entire stroke at a preset printing speed. During the printing process, the laser interferometer is synchronously triggered by the laser ruler position pulse as the trigger source to collect the sway angle, so as to obtain the sway angle error data and the stage position data.

3. The inkjet printing error compensation method according to claim 1, characterized in that, The process of acquiring environmental parameters from the environmental monitoring module, acquiring the original position signal of the platform from the laser ruler, and correcting the original position signal of the platform based on the environmental parameters to obtain the absolute position signal of the platform includes: Real-time environmental parameters are obtained from the environmental monitoring module; these environmental parameters include temperature, air pressure, and humidity. The original position signal of the platform is obtained from the laser ruler; The real-time air refractive index is calculated based on real-time environmental parameters, and the original position signal of the stage is corrected based on the real-time air refractive index to obtain the corrected position signal. The corrected position signal is converted into a pulse signal to obtain the absolute position signal of the platform.

4. The inkjet printing error compensation method according to claim 1, characterized in that, The process of using the absolute position signal of the platform as the query basis and calling the error compensation table to correct the nozzle coordinates to obtain the nozzle compensation coordinates includes: Using the absolute position signal of the stage as the query address, the stage yaw angle at the corresponding position is found from the error compensation table; The nozzle coordinates are obtained from the control device; the nozzle coordinates are the lateral distance of the nozzle relative to the center of the platform sway. The offset of the substrate below each nozzle due to the stage tilt is calculated based on the yaw angle and nozzle coordinates. The absolute position signal of the stage is corrected using the offset to obtain the nozzle compensation coordinates.

5. The inkjet printing error compensation method according to claim 1, characterized in that, The generation of the nozzle trigger signal based on the nozzle compensation coordinates includes: Obtain the preset target printing position from the control device; The nozzle compensation coordinates are compared with the preset target printing position in real time. When the nozzle compensation coordinates are greater than or equal to the preset target printing position, a printhead trigger signal is generated.

6. An inkjet printing error compensation system, characterized in that, The inkjet printing error compensation system includes a control device and a substrate stage, a laser interferometer, a laser ruler, and an environmental monitoring module electrically connected to the control device; the control device is used to execute the inkjet printing error compensation method as described in any one of claims 1-5.

7. The inkjet printing error compensation system according to claim 6, characterized in that: The substrate stage is used to support the glass substrate; The laser interferometer includes a laser, a first interferometer group, and a first reflector; the first reflector is rigidly fixed to the side of the substrate stage, and the laser, the first interferometer group, and the first reflector cooperate to form a measurement optical path for measuring the yaw angle of the substrate stage about the rotation axis; The laser ruler includes a bracket, a laser head, a second interferometer group, and a second reflector. The second reflector is mounted on the end face of the substrate stage. The laser head and the second interferometer group are mounted on the bracket, and the optical path of the laser head is parallel to the printing axis of the substrate stage. The laser head, the second interferometer group, and the second reflector cooperate to acquire the original position signal of the stage. The environmental monitoring module is used to monitor temperature, air pressure, humidity and carbon dioxide concentration in real time; The control device includes a host computer and a main control FPGA, which are electrically connected. The host computer is used to store the error compensation table, nozzle coordinates, and target printing position, while the main control FPGA is used to perform error compensation calculations and generate nozzle trigger signals.

8. An inkjet printing error compensation device, characterized in that, The inkjet printing error compensation device includes: a memory and at least one processor, wherein the memory stores instructions; At least one of the processors invokes the instructions in the memory to cause the inkjet printing error compensation device to perform the steps of the inkjet printing error compensation method as described in any one of claims 1-5.

9. A computer-readable storage medium storing instructions thereon, characterized in that, When the instructions are executed by the processor, they implement the steps of the inkjet printing error compensation method as described in any one of claims 1-5.

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