An automatic calibration method, device, equipment and medium of a printing nozzle

Abstract

The application discloses an automatic calibration method, device, equipment and medium of a printing nozzle. The automatic calibration method of the printing nozzle comprises the following steps: determining the circular ring calibration positions of at least two groups of multi-column printing nozzles and reference nozzles in the at least two groups of multi-column printing nozzles; performing a printing test based on the at least two groups of multi-column printing nozzles to obtain a printing graph to be corrected; determining printing calibration data matched with the reference nozzles according to the printing graph to be corrected and the circular ring calibration positions; and performing automatic calibration on the at least two groups of multi-column printing nozzles based on the printing calibration data. The technical scheme of the embodiment of the application can save labor cost and improve correction efficiency.

Description

Technical Field

[0001] This invention relates to the field of inkjet printer calibration technology, and in particular to an automatic calibration method, apparatus, equipment and medium for printheads. Background Technology

[0002] A printer is an automated device used to print graphics on PCD and FPC. The printing accuracy is the core indicator of a printer, and the accuracy of the printing head installation and adjustment is the most important factor affecting the printing accuracy.

[0003] Currently, the installation and adjustment of printheads generally involves two stages. The first stage is manual initial adjustment, where the printhead is fixed to the base with screws to ensure that the printhead's accuracy is within the millimeter level. The second stage involves manually comparing the printer's printing performance with the printed test strip to determine the printhead's adjustment parameters, which are then used to precisely adjust the printhead.

[0004] However, the accuracy of existing printheads relies on manual adjustment, and the calibration accuracy is overly dependent on the professional skills of the debugging personnel, which makes the adjustment time too long. It takes about 2-3 days to complete the adjustment of a multi-printhead printing machine, which seriously affects the calibration efficiency of the printing machine. Summary of the Invention

[0005] This invention provides an automatic calibration method, apparatus, equipment, and medium for printheads to solve the problems of high labor costs and low calibration efficiency in improving the printing accuracy of existing inkjet printers.

[0006] According to one aspect of the present invention, an automatic calibration method for a printhead is provided, comprising:

[0007] Determine the annular calibration positions of at least two sets of multi-column printheads, and the reference printhead in at least two sets of multi-column printheads;

[0008] A print test is performed using at least two sets of multi-column printheads to obtain a print image to be calibrated.

[0009] Based on the printout to be calibrated and the position of the circular calibration ring, determine the print calibration data that matches the reference printhead;

[0010] Automatic calibration is performed on at least two sets of multi-column printheads based on print calibration data.

[0011] According to another aspect of the present invention, an automatic calibration device for a printhead is provided, comprising:

[0012] The calibration position and reference printhead determination module is used to determine the annular calibration position of at least two sets of multi-column printheads, and the reference printhead in at least two sets of multi-column printheads;

[0013] The print pattern determination module is used to perform print tests based on at least two sets of multi-column printheads to obtain the print pattern to be calibrated.

[0014] The print calibration data determination module is used to determine the print calibration data that matches the reference printhead based on the print pattern to be calibrated and the position of the circular calibration ring.

[0015] An automatic calibration module is used to automatically calibrate at least two sets of multi-column printheads based on print calibration data.

[0016] According to another aspect of the present invention, a printing apparatus is provided, the printing apparatus comprising:

[0017] At least one processor; and

[0018] A memory communicatively connected to the at least one processor; wherein,

[0019] The memory stores a computer program that can be executed by the at least one processor, which enables the at least one processor to perform the automatic calibration method for the printhead according to any embodiment of the present invention.

[0020] According to another aspect of the present invention, a computer-readable storage medium is provided, the computer-readable storage medium storing computer instructions for causing a processor to execute and implement the automatic calibration method for a printhead according to any embodiment of the present invention.

[0021] The technical solution of this invention determines the annular calibration positions of at least two sets of multi-column printheads and a reference printhead among the at least two sets of multi-column printheads. Based on these at least two sets of multi-column printheads, a print test is performed to obtain a print image to be calibrated. Then, based on the print image to be calibrated and the annular calibration positions, print calibration data matching the reference printhead is determined. Furthermore, the printheads are automatically calibrated based on the print calibration data. In this solution, the print calibration data determined by the reference printhead through the annular calibration positions accurately represents the precise compensation value required for the printhead. Compensating the printheads using the print calibration data allows for automated and precise calibration of multiple sets of multi-column printheads. This solves the problems of high labor costs and low calibration efficiency in existing methods for improving the printing accuracy of inkjet printers, saving labor costs and improving calibration efficiency.

[0022] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 A flowchart illustrating an automatic calibration method for a printhead according to Embodiment 1 of the present invention;

[0025] Figure 2 A flowchart illustrating an automatic calibration method for a printhead according to Embodiment 2 of the present invention;

[0026] Figure 3 This is a schematic diagram of a test strip provided in Embodiment 2 of the present invention;

[0027] Figure 4 This is a schematic diagram of an automatic calibration device for a printhead provided in Embodiment 3 of the present invention;

[0028] Figure 5 A schematic diagram of a printing device that can be used to implement embodiments of the present invention is shown. Detailed Implementation

[0029] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0030] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0031] Example 1

[0032] Figure 1This is a flowchart of an automatic printhead calibration method provided in Embodiment 1 of the present invention. This embodiment is applicable to the efficient calibration of printheads in inkjet printers. The method can be executed by an automatic printhead calibration device, which can be implemented in hardware and / or software and can be configured in the printing equipment. Figure 1 As shown, the method includes:

[0033] Step 110: Determine the annular calibration position of at least two sets of multi-column printheads, and the reference printhead in at least two sets of multi-column printheads.

[0034] The circular calibration position can be the position of the circular ring used to test the printing accuracy of the printheads in the inkjet printer, i.e., the center coordinates of the calibration ring. The reference printhead can be used to perform horizontal calibration of the printheads arranged in the inkjet printer, so that at least two sets of multi-column printheads can print a single column of dots (such as text). For example, the reference printhead can be the first printhead in the first column of the first row of at least two sets of multi-column printheads.

[0035] In this embodiment of the invention, the circular calibration position of the test printhead can be set as needed, and a reference printhead can be determined from multiple printheads.

[0036] Optionally, in at least two groups of multi-column printheads, printheads located in the same row belong to one group, and each printhead can correspond to one column of calibration rings. For example, each printhead corresponds to one column of 5 calibration rings.

[0037] Step 120: Perform printing tests based on at least two sets of multi-column printheads to obtain the print image to be calibrated.

[0038] The print image to be calibrated can be an image printed by the print head during a print accuracy test.

[0039] In this embodiment of the invention, the print head can be triggered to print according to a pre-set test procedure, so that the print head can complete the printing test and the printed content can be used as the printing image to be corrected.

[0040] Step 130: Based on the printout to be calibrated and the position of the circular calibration ring, determine the print calibration data that matches the reference printhead.

[0041] The print calibration data can be data from printing calibration of the print head based on a reference print head.

[0042] In this embodiment of the invention, the printing points of each printhead in the print pattern to be calibrated can be analyzed, and the deviation between the printing points of each printhead and the matching circular calibration position can be calculated to determine the printing calibration data of the reference printhead, as well as the printing calibration data of other printheads based on the reference printhead.

[0043] In an optional embodiment of the present invention, while determining the printing calibration data matching the reference printhead, the method may further include: determining the vertical seam position of the target column printhead based on the print pattern to be calibrated, and obtaining the theoretical position of the vertical seam; calculating and displaying the vertical seam error based on the vertical seam position and the theoretical position of the vertical seam.

[0044] The target column printheads can be printheads with the same column number and belonging to adjacent rows. The vertical seam position can be the seam position between the print points of two adjacent printheads in the target column. The theoretical vertical seam position can be the seam position between two adjacent calibration rings, used to characterize the distance between the last calibration ring of one column and the first calibration ring of the next adjacent column. The vertical seam error can be the error between the vertical seam position and the theoretical vertical seam position.

[0045] In this embodiment of the invention, a target column of printheads can be determined, and the printing points of the target column of printheads can be determined from the print pattern to be corrected. Then, based on the printing points of the target column of printheads, the vertical seam position of the target column of printheads can be calculated, and the theoretical position of the vertical seam can be obtained. Based on the difference between the vertical seam position and the theoretical position of the vertical seam, the vertical seam position can be corrected to obtain the vertical seam error, and the vertical seam error can be displayed.

[0046] Step 140: Perform automatic calibration on at least two sets of multi-column printheads based on print calibration data.

[0047] In this embodiment of the invention, the printhead can be calibrated based on print calibration data without manual intervention, which greatly reduces the problem of low calibration efficiency caused by manual calibration.

[0048] The technical solution of this invention determines the annular calibration positions of at least two sets of multi-column printheads and a reference printhead among the at least two sets of multi-column printheads. Based on these at least two sets of multi-column printheads, a print test is performed to obtain a print image to be calibrated. Then, based on the print image to be calibrated and the annular calibration positions, print calibration data matching the reference printhead is determined. Furthermore, the printheads are automatically calibrated based on the print calibration data. In this solution, the print calibration data determined by the reference printhead through the annular calibration positions accurately represents the precise compensation value required for the printhead. Compensating the printheads using the print calibration data allows for automated and precise calibration of multiple sets of multi-column printheads. This solves the problems of high labor costs and low calibration efficiency in existing methods for improving the printing accuracy of inkjet printers, saving labor costs and improving calibration efficiency.

[0049] Example 2

[0050] Figure 2 This is a flowchart of an automatic printhead calibration method according to Embodiment 2 of the present invention. This embodiment is a specific embodiment based on the above embodiment, and provides specific optional implementation methods for determining the print calibration data matching the reference printhead based on the print pattern to be calibrated and the circular calibration position. Figure 2 As shown, the method includes:

[0051] Step 210: Determine the annular calibration position of at least two sets of multi-column printheads, and the reference printhead in at least two sets of multi-column printheads.

[0052] In an optional embodiment of the present invention, determining the circular calibration position of at least two sets of multi-column printheads may include: obtaining the image capture position of a binocular camera in a printing carriage where the printheads are installed; and recording the circular calibration position based on the binocular camera and the image capture position.

[0053] In this embodiment of the invention, a binocular camera is arranged in the printing carriage where the print head is installed. By parsing the file describing the standard position of the ring, the image-taking position of the binocular camera in the printing carriage is obtained. When the binocular camera reaches the image-taking position, it is triggered to take a picture, determine the ring calibration position, and record the ring calibration position.

[0054] Step 220: Perform printing tests based on at least two sets of multi-column printheads to obtain the print image to be calibrated.

[0055] In an optional embodiment of the present invention, while performing printing tests based on at least two sets of multi-column printheads, the method may further include: acquiring a first calibration image captured by a first camera in a binocular camera and a second calibration image captured by a second camera; determining camera calibration parameters based on the first calibration image, the second calibration image, and the circular calibration position; and calibrating the first camera and / or the second camera based on the camera calibration parameters.

[0056] The first camera can be the left eye camera in a stereo camera system. The second camera can be the right eye camera in a stereo camera system. The first calibration image can be an image captured by the first camera at the designated shooting position. The second calibration image can be an image captured by the second camera when the first camera is at the designated shooting position. Camera calibration parameters can be used to perform parameter calibration on the stereo camera.

[0057] In this embodiment of the invention, a first calibration image captured by the first camera and a second calibration image captured by the second camera in a binocular camera can be acquired to determine the calibration position of the calibration ring closest to the first calibration image. Then, based on the deviation between the first calibration image and the calibration position of the ring, and the deviation between the second calibration image and the calibration position of the ring, camera correction parameters are calculated. Finally, the first camera and / or the second camera that need to be corrected are corrected according to the camera correction parameters.

[0058] Step 230: Determine the external compensation value based on the ring calibration position matched by the reference printhead, the ring calibration position of the target column calibration ring, and the printout to be calibrated.

[0059] The target column calibration ring can be a column-distributed calibration ring outside the calibration ring corresponding to the reference printhead. The external compensation value can be the compensation value in the horizontal direction of the calibration printhead.

[0060] In this embodiment of the invention, the calibration rings distributed in the column direction outside the calibration ring corresponding to the reference printhead are taken as the target column direction calibration rings, thereby determining the deviation between the ring calibration position of the target column direction calibration ring and the ring calibration position matching the reference printhead. The deviation is then corrected using the print pattern to be corrected, that is, the deviation is corrected based on the error in the actual printing process of the printhead, and an external compensation value is obtained.

[0061] In an optional embodiment of the present invention, determining the external compensation value based on the annular calibration position matched with the reference printhead, the annular calibration position of the target column calibration ring, and the print image to be calibrated may include: determining a first external compensation value based on the annular calibration position matched with the reference printhead, the annular calibration position of the target column calibration ring, and the print image to be calibrated; and determining a second external compensation value based on the annular calibration position of the printhead in the target column calibration ring that is parallel to the reference printhead, the annular calibration position matched with the reference printhead, and the print image to be calibrated.

[0062] The first outer group compensation value can be an external compensation value for printheads in different rows of the reference printhead. The second outer group compensation value can be an external compensation value for different printheads in the same row, to ensure that the print dots of the printheads in the same row maintain a preset spacing.

[0063] In this embodiment of the invention, the lateral mean (i.e., horizontal position mean) of the annular calibration position matching the reference printhead is first determined. Then, based on the annular calibration position of the target column calibration ring and the lateral mean, the deviation value (referred to as the first deviation) between the target column calibration ring and the lateral mean is determined. Then, based on the error between the printhead print point in the print image to be corrected and the corresponding annular calibration position, the deviation value between the target column calibration ring and the lateral mean is corrected to obtain the first external compensation value. Further, the annular calibration position of the printhead in the target column calibration ring that is in the same row as the reference printhead is determined. Then, the deviation value (referred to as the second deviation) between the annular calibration position of the printhead in the target column calibration ring that is in the same row as the reference printhead and the annular calibration position matching the reference printhead is calculated. The second deviation is corrected based on the error between the printhead print point in the print image to be corrected and the corresponding annular calibration position to obtain the second external compensation value.

[0064] Step 240: Calculate the rotation angle compensation value and the expansion / contraction compensation value.

[0065] The rotation angle compensation value can be the compensation value when the midpoint line connecting all printing points of the print head is calibrated to be horizontal. The expansion and contraction compensation value can be used to adjust the expansion and contraction of the print head to achieve the data for normal printing.

[0066] In this embodiment of the invention, the offset angle of the printhead print point relative to the horizontal line is determined based on the print image to be corrected, and the rotation angle compensation value of the compensation table is determined according to the offset angle. The expansion and contraction compensation value can also be determined according to the horizontal and vertical intervals of adjacent printhead print points.

[0067] In an optional embodiment of the present invention, calculating the rotation angle compensation value and the expansion / contraction compensation value may include: determining the rotation angle compensation value based on the ring calibration position of the target row calibration ring and the print image to be calibrated; and calculating the expansion / contraction compensation value of the current print head based on the target adjacent print points of the current print head in the print image to be calibrated.

[0068] The target row alignment calibration ring can be an alignment ring arranged at preset intervals. The target adjacent print points can be the left and right adjacent print points and the top and bottom adjacent print points printed by the current print head.

[0069] In this embodiment of the invention, a target row calibration ring can be set in the test strip, and the ring calibration position of the target row calibration ring can be obtained. Then, the printing point of the print head that matches the target row calibration ring in the print image to be calibrated can be determined. Based on the angle formed by the line connecting the midpoints of the printing points and the line connecting the midpoint of the ring calibration position of the target row calibration ring, the rotation angle compensation value can be determined. Then, the target adjacent printing point of the current print head in the print image to be calibrated can be obtained. Based on the left and right adjacent printing points in the target adjacent printing points, the lateral expansion and contraction compensation value can be calculated. Based on the upper and lower adjacent printing points in the target adjacent printing points, the longitudinal expansion and contraction compensation value can be calculated.

[0070] Step 250: Use the external compensation value, rotation angle compensation value, and expansion / contraction compensation value as printing calibration data to match the reference printhead.

[0071] Step 260: Perform automatic calibration on at least two sets of multi-column printheads based on print calibration data.

[0072] Optionally, the print calibration data can be automatically compensated to the printer, so that the printer can automatically calibrate the print head according to the print calibration data and display the compensation value of the print head through the interface.

[0073] Figure 3 This is a schematic diagram of a test strip provided in Embodiment 2 of the present invention, as shown below. Figure 3 As shown, each printhead corresponds to 5 calibration rings, and the target row calibration rings are formed by 5 calibration rings that are equally spaced in the horizontal direction of columns a, c, d, e, and f.

[0074] In a specific example, after the user clicks the printhead status acquisition button, the XML file describing the ring calibration position can be parsed to obtain the photo position. This then drives the binocular camera in the printer to reach the photo position and trigger the camera to take a picture. The camera then identifies the calibration position of the calibration ring in the captured image and writes the ring calibration position into a CSV file. Based on the algorithm, the external compensation value, rotation angle compensation value, expansion and contraction compensation value, and camera correction parameters are determined. Vertical seam error can also be displayed through an external tool. This improves the maintainability, operability, and accuracy of the printer without increasing hardware costs, and reduces time consumption (the calibration time for a printer with 18 printheads is less than 180 seconds, far less than the time required for manual adjustment).

[0075] Optionally, a script for printing test strips can be set in the printer's control software. When the user clicks on print settings or nozzle check, a parameter calibration interface is displayed, allowing the user to click on vertical calibration, step calibration, bidirectional calibration, etc., to complete the printing of the test strips.

[0076] The technical solution of this invention determines the annular calibration positions of at least two sets of multi-column printheads and the reference printhead in at least two sets of multi-column printheads, thereby performing a print test based on at least two sets of multi-column printheads to obtain a print image to be calibrated. Based on the annular calibration position matched by the reference printhead, the annular calibration position of the target column calibration ring, and the print image to be calibrated, the outer group compensation value is determined. The rotation angle compensation value and the expansion / contraction compensation value are further calculated. The outer group compensation value, the rotation angle compensation value, and the expansion / contraction compensation value are used as print calibration data matched with the reference printhead, so as to automatically calibrate the printhead based on the print calibration data. In this solution, the printing calibration data determined by the reference printhead through the circular calibration position can accurately represent the precise value required for printhead compensation. By compensating the printhead with the printing calibration data, multiple sets and columns of printheads can be automatically and accurately calibrated. Furthermore, it achieves multi-dimensional compensation for the printhead, ensuring the expansion and contraction rate of the printing result, the consistency of the lateral position of the print dots in the same column, and the absence of tilt angle for horizontal print dots. This solves the problems of high labor costs and low calibration efficiency in improving the printing accuracy of existing inkjet printers, saving labor costs and improving calibration efficiency.

[0077] Example 3

[0078] Figure 4 This is a schematic diagram of an automatic printhead calibration device provided in Embodiment 3 of the present invention. Figure 4 As shown, the device includes:

[0079] The calibration position and reference printhead determination module 310 is used to determine the annular calibration position of at least two sets of multi-column printheads, and the reference printhead in at least two sets of multi-column printheads;

[0080] The print pattern determination module 320 is used to perform print tests based on at least two sets of multi-column printheads to obtain the print pattern to be calibrated.

[0081] The print calibration data determination module 330 is used to determine the print calibration data that matches the reference printhead based on the print pattern to be calibrated and the position of the circular calibration ring.

[0082] Automatic calibration module 340 is used to automatically calibrate at least two sets of multi-column printheads based on print calibration data.

[0083] The technical solution of this invention determines the annular calibration positions of at least two sets of multi-column printheads and a reference printhead among the at least two sets of multi-column printheads. Based on these at least two sets of multi-column printheads, a print test is performed to obtain a print image to be calibrated. Then, based on the print image to be calibrated and the annular calibration positions, print calibration data matching the reference printhead is determined. Furthermore, the printheads are automatically calibrated based on the print calibration data. In this solution, the print calibration data determined by the reference printhead through the annular calibration positions accurately represents the precise compensation value required for the printhead. Compensating the printheads using the print calibration data allows for automated and precise calibration of multiple sets of multi-column printheads. This solves the problems of high labor costs and low calibration efficiency in existing methods for improving the printing accuracy of inkjet printers, saving labor costs and improving calibration efficiency.

[0084] Optionally, the calibration position and reference printhead determination module 310 includes a calibration position determination unit, used to obtain the image capture position of the binocular camera in the printing carriage where the printhead is installed; and to record the circular calibration position based on the binocular camera and the image capture position.

[0085] Optionally, the automatic calibration device for the printhead further includes a camera calibration module, used to acquire a first calibration image captured by the first camera in the binocular camera and a second calibration image captured by the second camera; determine camera calibration parameters based on the first calibration image, the second calibration image and the circular calibration position; and calibrate the first camera and / or the second camera based on the camera calibration parameters.

[0086] Optionally, the print calibration data determination module 330 includes a first compensation value determination unit, a second compensation value determination unit, and a print calibration data determination unit. The first compensation value determination unit is used to determine the external compensation value based on the annular calibration position matched by the reference printhead, the annular calibration position of the target column calibration ring, and the print image to be calibrated. The second compensation value determination unit is used to calculate the rotation angle compensation value and the expansion / contraction compensation value. The print calibration data determination unit is used to use the external compensation value, the rotation angle compensation value, and the expansion / contraction compensation value as print calibration data matched with the reference printhead.

[0087] Optionally, the first compensation value determining unit is specifically used to determine a first outer group compensation value based on the annular calibration position matching the reference printhead, the annular calibration position of the target column calibration ring, and the print image to be calibrated; and to determine a second outer group compensation value based on the annular calibration position of the printhead in the target column calibration ring that is in the same row as the reference printhead, the annular calibration position matching the reference printhead, and the print image to be calibrated.

[0088] Optionally, the second compensation value determination unit is specifically used to determine the rotation angle compensation value based on the ring calibration position of the target row calibration ring and the print image to be calibrated; and to calculate the expansion and contraction compensation value of the current print head based on the target adjacent print points of the current print head in the print image to be calibrated.

[0089] Optionally, the automatic calibration device for the printhead also includes a vertical seam error display module, used to determine the vertical seam position of the target column printhead according to the print pattern to be calibrated, and obtain the theoretical position of the vertical seam; and to calculate and display the vertical seam error based on the vertical seam position and the theoretical position of the vertical seam.

[0090] The automatic printhead calibration device provided in this embodiment of the invention can execute the automatic printhead calibration method provided in any embodiment of the invention, and has the corresponding functional modules and beneficial effects of the method.

[0091] Example 4

[0092] Figure 5 A schematic diagram of a printing apparatus that can be used to implement embodiments of the present invention is shown. The components shown herein, their connections and relationships, and their functions are merely examples and are not intended to limit the implementation of the invention described and / or claimed herein.

[0093] like Figure 5As shown, the printing device 10 includes at least one processor 11 and a memory, such as a read-only memory (ROM) 12 or a random access memory (RAM) 13, communicatively connected to the at least one processor 11. The memory stores computer programs executable by the at least one processor. The processor 11 can perform various appropriate actions and processes based on the computer program stored in the ROM 12 or loaded into the RAM 13 from storage unit 18. The RAM 13 may also store various programs and data required for the operation of the printing device 10. The processor 11, ROM 12, and RAM 13 are interconnected via a bus 14. An input / output (I / O) interface 15 is also connected to the bus 14.

[0094] Multiple components in the printing device 10 are connected to the I / O interface 15, including: an input unit 16, such as a keyboard, mouse, etc.; an output unit 17, such as various types of displays, speakers, etc.; a storage unit 18, such as a disk, optical disk, etc.; and a communication unit 19, such as a network card, modem, wireless transceiver, etc. The communication unit 19 allows the printing device 10 to exchange information / data with other devices through computer networks such as the Internet and / or various telecommunications networks.

[0095] Processor 11 can be a variety of general-purpose and / or special-purpose processing components with processing and computing capabilities. Some examples of processor 11 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various special-purpose artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, a digital signal processor (DSP), and any suitable processor, controller, microcontroller, etc. Processor 11 performs the various methods and processes described above, such as the automatic calibration method for a printhead.

[0096] In some embodiments, the automatic printhead calibration method can be implemented as a computer program tangibly contained in a computer-readable storage medium, such as storage unit 18. In some embodiments, part or all of the computer program can be loaded and / or installed on the printing device 10 via ROM 12 and / or communication unit 19. When the computer program is loaded into RAM 13 and executed by processor 11, one or more steps of the automatic printhead calibration method described above can be performed. Alternatively, in other embodiments, processor 11 can be configured to perform the automatic printhead calibration method by any other suitable means (e.g., by means of firmware).

[0097] Various embodiments of the systems and techniques described above herein can be implemented in digital electronic circuit systems, integrated circuit systems, field-programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), application-specific standard products (ASSPs), systems-on-a-chip (SoCs), payload-programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various embodiments may include implementations in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which may be a dedicated or general-purpose programmable processor, capable of receiving data and instructions from a storage system, at least one input device, and at least one output device, and transmitting data and instructions to the storage system, the at least one input device, and the at least one output device.

[0098] Computer programs used to implement the methods of the present invention may be written in any combination of one or more programming languages. These computer programs may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, such that when executed by the processor, the computer programs cause the functions / operations specified in the flowcharts and / or block diagrams to be performed. The computer programs may be executed entirely on a machine, partially on a machine, or as a standalone software package, partially on a machine and partially on a remote machine, or entirely on a remote machine or server.

[0099] In the context of this invention, a computer-readable storage medium can be a tangible medium that may contain or store a computer program for use by or in conjunction with an instruction execution system, apparatus, or device. A computer-readable storage medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination thereof. Alternatively, a computer-readable storage medium may be a machine-readable signal medium. More specific examples of machine-readable storage media include electrical connections based on one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fibers, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof.

[0100] To provide interaction with the user, the systems and techniques described herein can be implemented on a printing device having: a display device for displaying information to the user (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor); and a keyboard and pointing device (e.g., a mouse or trackball) through which the user provides input to the printing device. Other types of devices can also be used to provide interaction with the user; for example, feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form (including sound input, voice input, or tactile input).

[0101] The systems and technologies described herein can be implemented in computing systems that include backend components (e.g., as data servers), or computing systems that include middleware components (e.g., application servers), or computing systems that include frontend components (e.g., user computers with graphical user interfaces or web browsers through which users can interact with implementations of the systems and technologies described herein), or any combination of such backend, middleware, or frontend components. The components of the system can be interconnected via digital data communication of any form or medium (e.g., communication networks). Examples of communication networks include local area networks (LANs), wide area networks (WANs), blockchain networks, and the Internet.

[0102] A computing system can include clients and servers. Clients and servers are generally located far apart and typically interact through communication networks. The client-server relationship is created by computer programs running on the respective computers and having a client-server relationship with each other. The server can be a cloud server, also known as a cloud computing server or cloud host, which is a hosting product within the cloud computing service system to address the shortcomings of traditional physical hosts and VPS services, such as high management difficulty and weak business scalability.

[0103] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0104] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A method of automatic calibration of a print head, characterized by, The method comprises the following steps: determining the circular calibration positions of at least two groups of multi-column printing nozzles and reference nozzles in the at least two groups of multi-column printing nozzles; performing a printing test based on the at least two groups of multi-column printing nozzles to obtain a to-be-corrected printing image; determining printing calibration data matched with the reference nozzles according to the to-be-corrected printing image and the circular calibration positions; automatically calibrating the at least two groups of multi-column printing nozzles based on the printing calibration data; the step of determining the printing calibration data matched with the reference nozzles according to the to-be-corrected printing image and the circular calibration positions comprises the following steps: determining an outer group compensation value according to the circular calibration position matched with the reference nozzles, the circular calibration position of the target column to the calibration circle and the to-be-corrected printing image; calculating a rotation angle compensation value and a swelling and shrinking compensation value; and taking the outer group compensation value, the rotation angle compensation value and the swelling and shrinking compensation value as the printing calibration data matched with the reference nozzles.

2. The method of claim 1, wherein, the step of determining the circular calibration positions of the at least two groups of multi-column printing nozzles comprises the following steps: obtaining a photographing position of a binocular camera in a printing trolley on which the printing nozzles are installed; recording the circular calibration positions according to the binocular camera and the photographing position.

3. The method of claim 2, wherein, the step of performing the printing test based on the at least two groups of multi-column printing nozzles comprises the following steps: obtaining a first calibration image collected by a first camera and a second calibration image collected by a second camera in the binocular camera; determining camera correction parameters according to the first calibration image, the second calibration image and the circular calibration positions; correcting the first camera and / or the second camera according to the camera correction parameters.

4. The method of claim 1, wherein, the step of determining the outer group compensation value according to the circular calibration position matched with the reference nozzles, the circular calibration position of the target column to the calibration circle and the to-be-corrected printing image comprises the following steps: determining a first outer group compensation value according to the circular calibration position matched with the reference nozzles, the circular calibration position of the target column to the calibration circle and the to-be-corrected printing image; determining a second outer group compensation value based on the circular calibration position of the printing nozzle in the same row as the reference nozzle in the target column to the calibration circle, the circular calibration position matched with the reference nozzle and the to-be-corrected printing image.

5. The method of claim 1, wherein, the step of calculating the rotation angle compensation value and the swelling and shrinking compensation value comprises the following steps: determining the rotation angle compensation value according to the circular calibration position of the target row to the calibration circle and the to-be-corrected printing image; calculating the swelling and shrinking compensation value of the current printing nozzle according to the target adjacent printing point of the current printing nozzle in the to-be-corrected printing image.

6. The method of claim 1, wherein, the step of determining the printing calibration data matched with the reference nozzles comprises the following steps: determining a vertical direct seam position of the target column nozzle according to the to-be-corrected printing image and obtaining a vertical direct seam theoretical position; calculating and displaying a vertical direct seam error according to the vertical direct seam position and the vertical direct seam theoretical position.

7. An apparatus for automatic calibration of a print head, characterized by The method comprises the following steps: a calibration position and reference nozzle determination module is configured to determine the circular calibration positions of at least two groups of multi-column printing nozzles and reference nozzles in the at least two groups of multi-column printing nozzles; The printing test is performed based on the at least two groups of multi-column printing nozzles, and a printing graph to be corrected is obtained; The printing calibration data determination module is configured to determine printing calibration data matched with the reference nozzle according to the printing graph to be corrected and the annular calibration position; The automatic calibration module is configured to perform automatic calibration on the at least two groups of multi-column printing nozzles based on the printing calibration data; The printing calibration data determination module comprises a first compensation value determination unit, a second compensation value determination unit and a printing calibration data determination unit; The first compensation value determination unit is configured to determine an outer group compensation value according to the annular calibration position of the reference nozzle, the annular calibration position of the target column direction calibration annulus and the printing graph to be corrected; The second compensation value determination unit is configured to calculate a rotation angle compensation value and a swelling and shrinking compensation value; The printing calibration data determination unit is configured to take the outer group compensation value, the rotation angle compensation value and the swelling and shrinking compensation value as the printing calibration data matched with the reference nozzle.

8. A printing device, characterized by, The printing device comprises: at least one processor; and a memory connected with the at least one processor in communication; wherein the memory stores a computer program executable by the at least one processor, and the computer program is executed by the at least one processor to enable the at least one processor to execute the automatic calibration method of the printing nozzle in any one of claims 1-6.

9. A computer-readable storage medium, characterized in that, The computer readable storage medium stores computer instructions for enabling the processor to execute the automatic calibration method of the printing nozzle in any one of claims 1-6 when executed by the processor.

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