Calibration method of printing device, electronic device, printing system, and storage medium

Abstract

The application discloses a calibration method of a printing device, an electronic device, a printing system and a storage medium, relates to the field of inkjet printing technology, and discloses a calibration method of a printing device, which comprises the following steps: according to a calibration instruction, a calibration pattern is printed on a printing medium by controlling the printing device, the calibration pattern comprises a main scale and a secondary scale, the graduation value of the main scale is different from the graduation value of the secondary scale, and the main scale and the secondary scale are patterns printed before and after a calibration action, respectively; a calibration image is obtained, the calibration image is obtained by shooting the calibration pattern; actual deviation data between the main scale and the secondary scale is recognized according to the calibration image; offset error of the printing device is calculated according to the actual deviation data and theoretical deviation data between the main scale and the secondary scale; and calibration parameters of the printing device are generated according to the offset error. The application reduces printing deviation and improves printing accuracy.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of inkjet printing technology, and in particular to a calibration method of a printing device, an electronic device, a printing system and a storage medium. BACKGROUND

[0002] The use of a printhead of an inkjet printing device in high-precision printing, a slight deviation, such as an inaccurate paper travel distance, or a drop deviation caused by a speed, or a nozzle position offset, etc., can result in poor printing effect. In the related art, the calibration scheme relies on high-precision optical sensors or scanner calibration, and the calibration process is complex, and manual calibration cannot obtain accurate offset error, resulting in poor calibration effect of control parameters. SUMMARY

[0003] The main purpose of the present application is to provide a calibration method of a printing device, an electronic device, a printing system and a storage medium, aiming at solving the technical problem of poor calibration effect of control parameters.

[0004] To achieve the above-mentioned purpose, the present application provides a calibration method of a printing device, which comprises:

[0005] According to the calibration instruction, the printing device prints a calibration pattern on the printing medium, the calibration pattern comprises a main scale and a secondary scale, the division value of the main scale is different from the division value of the secondary scale, and the main scale and the secondary scale are respectively the patterns printed before and after the calibration action;

[0006] Obtain a calibration image, the calibration image is obtained by shooting the calibration pattern;

[0007] According to the calibration image, the actual deviation data between the main scale and the secondary scale is identified;

[0008] According to the actual deviation data and the theoretical deviation data between the main scale and the secondary scale, the offset error of the printing device is calculated;

[0009] According to the offset error, the calibration parameters of the printing device are generated.

[0010] In an embodiment, the step of identifying the actual deviation data between the main scale and the secondary scale according to the calibration image comprises:

[0011] According to the calibration image, the distance between the zero scale of the main scale and the zero scale of the secondary scale is determined to obtain the actual deviation data.

[0012] In an embodiment, the step of determining the distance between the zero scale of the main scale and the zero scale of the secondary scale according to the calibration image comprises:

[0013] identifying a main ruler scale value in the calibration image, which is before the zero scale of the secondary ruler and closest to the zero scale of the secondary ruler;

[0014] identifying a secondary ruler scale value in the calibration image, which is coincident with the scale of the main ruler;

[0015] determining the distance between the zero scale of the main ruler and the zero scale of the secondary ruler according to the main ruler scale value and the secondary ruler scale value.

[0016] In an embodiment, the division value of the main ruler is the length of a plurality of ink drop points; the step of determining the distance between the zero scale of the main ruler and the zero scale of the secondary ruler according to the main ruler scale value and the secondary ruler scale value comprises:

[0017] determining the number of ink drop points that are different between the zero scale of the main ruler and the zero scale of the secondary ruler according to the main ruler scale value and the secondary ruler scale value;

[0018] calculating the distance between the zero scale of the main ruler and the zero scale of the secondary ruler according to the length of each ink drop point and the number of ink drop points that are different.

[0019] In an embodiment, after the step of generating the calibration parameter of the printing device according to the offset error, the method further comprises:

[0020] controlling the printing head to re-print the calibration pattern based on the calibration parameter;

[0021] obtaining a reference image corresponding to the re-printed calibration pattern;

[0022] identifying actual reference offset data between the main ruler and the secondary ruler according to the reference image;

[0023] calculating an offset reference error of the printing device according to the actual reference offset data and theoretical offset data between the main ruler and the secondary ruler;

[0024] if the offset reference error is less than a preset error threshold, saving the calibration parameter;

[0025] if the offset reference error is greater than the error threshold, generating the calibration parameter again according to the offset reference error, and performing the step of recalibrating the printing device until the offset reference error is less than the preset error threshold.

[0026] In an embodiment, before the step of identifying the actual offset data between the main ruler and the secondary ruler according to the calibration image, the method further comprises:

[0027] identifying a line missing area in the calibration image;

[0028] Filling the line missing area.

[0029] In an embodiment, if the calibration instruction indicates step calibration, the step of controlling the printing device to print the calibration pattern on the printing medium comprises:

[0030] controlling the print head of the printing device to print the main ruler;

[0031] After printing the main ruler, a first calibration action is performed, the first calibration action comprising: controlling the printing medium to move a preset distance in a first direction, and moving the print head in a second direction so that the print head is located on one side of the main ruler in the second direction, the second direction being perpendicular to the first direction;

[0032] controlling the print head to print the secondary ruler;

[0033] and / or,

[0034] If the calibration instruction indicates bidirectional calibration, or pitch calibration or color calibration, the step of controlling the printing device to print the calibration pattern on the printing medium comprises:

[0035] moving the print head from the starting position to a preset position in the positive direction of the second direction, and controlling the print head to print the main ruler;

[0036] After printing the main ruler, a second calibration action is performed, the second calibration action comprising: moving the print head to an end position in the positive direction of the first direction; moving the print head from the end position to the preset position in the negative direction of the first direction and moving the printing medium, moving the printing medium in the first direction so that the print head is located on one side of the main ruler in the first direction;

[0037] controlling the print head to print the secondary ruler.

[0038] In an embodiment, the step of obtaining the calibration image comprises:

[0039] controlling the camera of the printing device to capture the calibration pattern to obtain the calibration image.

[0040] In addition, to achieve the above object, the present application also provides an electronic device, which comprises: a memory, a processor, and a computer program stored in the memory and executable on the processor, the computer program being configured to implement the steps of the calibration method of the printing device as described above.

[0041] In addition, to achieve the above object, the present application also provides a printing device, which comprises:

[0042] a communication component configured to receive a calibration file, the calibration file comprising calibration parameters obtained based on the calibration method of the printing device as described above;

[0043] a print head configured to print a pattern;

[0044] a processor configured to control the print head to print a pattern based on the calibration file.

[0045] In addition, to achieve the above object, the present application further provides a printing system, comprising a host computer and a printing device, wherein the host computer is in communication connection with the printing device.

[0046] The printing device is configured to print a calibration pattern based on a calibration instruction.

[0047] The host computer is configured to: issue the calibration instruction to the printing device, and obtain calibration parameters based on the calibration method of the printing device as described above.

[0048] In addition, to achieve the above object, the present application further provides a computer readable storage medium, wherein the storage medium stores a computer program, and the computer program, when executed by a processor, implements the steps of the calibration method of the printing device as described above.

[0049] In addition, to achieve the above object, the present application further provides a computer program product, wherein the computer program product comprises a computer program, and the computer program, when executed by a processor, implements the steps of the calibration method of the printing device as described above.

[0050] The one or more technical solutions provided by the present application have at least the following technical effects:

[0051] The main ruler as the reference pattern before the calibration action can provide an explicit comparison reference for the printed copy ruler after the calibration action. By comparing the actual deviation data between the main ruler and the copy ruler of the calibration pattern with the theoretical deviation data, the offset error of the printing device can be accurately calculated. The calibration parameters generated by using the offset error can effectively correct the printing position deviation of the printing device, ensure that the print head moves according to the predetermined path or distance, thereby improving the printing precision and accuracy, and realizing the automatic calibration of the printing device, reducing the manual intervention, and reducing the maintenance cost and operation complexity. BRIEF DESCRIPTION OF DRAWINGS

[0052] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and serve to explain the principles of the present application together with the specification.

[0053] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the accompanying drawings needed to be used in the embodiments or prior art description will be briefly introduced as follows. Obviously, the drawings can also provide further drawings based on these drawings for those of ordinary skill in the art without any creative effort.

[0054] Figure 1 The flowchart provided by the calibration method of the printing device in Embodiment One of the present application;

[0055] Figure 2 The structure diagram of the printing device in the present application;

[0056] Figure 3 The schematic diagram of the calibration image in the calibration method of the printing device in the present application;

[0057] Figure 4 The schematic diagram of the printing principle and the actual printing image in the present application;

[0058] Figure 5 The brief flowchart provided by the calibration method of the printing device in Embodiment One of the present application;

[0059] Figure 6 The flowchart provided by the calibration method of the printing device in Embodiment Two of the present application;

[0060] Figure 7 The flowchart provided by the calibration method of the printing device in Embodiment Three of the present application;

[0061] Figure 8 The flowchart provided by the calibration method of the printing device in Embodiment Four of the present application;

[0062] Figure 9 Another flowchart provided by the calibration method of the printing device in Embodiment Four of the present application;

[0063] Figure 10 The device structure diagram of the hardware running environment involved in the calibration method of the printing device in the embodiments of the present application;

[0064] Figure 11 The structure diagram of the printing device in the present application;

[0065] Figure 12 The structure diagram of the printing system in the present application.

[0066] The object implementation, functional features and advantages of the present application will be further described with reference to the embodiments and the accompanying drawings. DETAILED DESCRIPTION

[0067] It should be understood that the specific embodiments described herein are merely used to explain the technical solutions of the present application and are not intended to limit the present application.

[0068] In order to better understand the technical solution of the present application, a detailed description will be given below in conjunction with the accompanying drawings and specific implementation methods.

[0069] The main solution of the embodiment of the present application is: according to the calibration instruction, control the printing device to print a calibration pattern on the printing medium; obtain a calibration image; identify the actual deviation data between the main scale and the secondary scale based on the calibration image; calculate the offset error of the printing device based on the actual deviation data and the theoretical deviation data between the main scale and the secondary scale; and generate calibration parameters of the printing device based on the offset error.

[0070] In this embodiment, for ease of description, the electronic device is used as the execution subject for explanation.

[0071] Since existing calibration schemes rely on high-precision optical sensors or scanner calibration, the calibration process is complicated, and manual calibration cannot obtain accurate offset errors, resulting in poor calibration effects of control parameters.

[0072] The present application provides a solution in which the main scale serves as a reference pattern before the calibration action, and can provide a clear comparison benchmark for the duplicate scale printed after the calibration action. By comparing the actual deviation data between the main scale and duplicate scale of the calibration pattern with the theoretical deviation data, the offset error of the printing device can be accurately calculated. The calibration parameters are generated by using this offset error, which can effectively correct the printing position deviation of the printing device, ensuring that the print head moves according to the predetermined path or distance, thereby improving the precision and accuracy of printing, and realizing automatic calibration of the printing device, reducing manual intervention, maintenance costs and operational complexity.

[0073] It should be noted that the execution subject of this embodiment can be a computing service device with data processing, network communication, and program execution functions, such as a tablet computer, personal computer, mobile phone, or other electronic device, a printing device, etc. The following uses electronic devices as an example to illustrate this embodiment and the following embodiments.

[0074] Printing equipment includes inkjet printing equipment, etc. Figure 1 The printing device 200 includes a carriage 210, which is provided with a camera 212 and a print head 211. The number of the print head 211 can be one or more. The printing device 200 can be a DTF (Direct-to-Film) printing device or other inkjet printing device, wherein Figure 1Taking a DTF printer as an example. A PET (polyethylene terephthalate) film is used as a printing medium, and the PET film has the characteristics of soft skin and ink absorption printing. An image is directly printed on the printing medium 220, such as a PET film, by the printing device 200, and then the pattern can be transferred to various substrates, such as fabrics, water cups, hats, etc. by heat pressing or the like.

[0075] Based on this, the calibration method of the printing device provided in the embodiments of the present application is described with reference to Figure 2 , Figure 2 The flowchart of the first embodiment of the calibration method of the printing device of the present application is shown in the figure.

[0076] In this embodiment, the calibration method of the printing device includes steps S10-S50:

[0077] Step S10, according to the calibration instruction, control the printing device to print a calibration pattern on the printing medium, the calibration pattern includes a main scale and a secondary scale, the graduation value of the main scale is different from the graduation value of the secondary scale, the main scale and the secondary scale are respectively the patterns printed before and after the calibration action.

[0078] It should be noted that the calibration instruction is used to calibrate the current control parameters of the printing device. Alternatively, the calibration instruction can be a calibration instruction input by the user in the printing device, or a calibration instruction sent by the host computer to the printing device.

[0079] Different calibration instructions correspond to different calibration actions, wherein the calibration action includes at least one of the moving direction, the moving distance of the printing medium, the moving direction, the moving distance of the print head. The main scale is the pattern printed before the calibration action, and the secondary scale is the pattern printed after the calibration action. The main scale as a reference pattern before the calibration action can provide a clear contrast reference for the secondary scale printed after the calibration action. By comparing the actual deviation data between the main scale and the secondary scale, the offset error of the printing device in the calibration action can be accurately identified.

[0080] In order to be suitable for different calibration schemes and enhance the universality, the calibration pattern includes a step calibration pattern, a bidirectional calibration pattern, a color registration calibration pattern or a pitch calibration pattern, etc., which is not limited to the above pattern types. Different calibration patterns can be used to realize different calibrations.

[0081] Need to explain, step calibration is the process of accurate adjustment of the step error of the stepper motor in the printing device, to ensure the positioning accuracy and printing quality in the printing process. Among them, the stepper motor is a key component in the printing device for accurately controlling the stepping distance of the printing medium, and the purpose of step calibration is to calibrate the stepping error of the printing medium, to ensure that the distance of the printing medium is consistent in each step during the printing process of the printing device, so as to ensure that the printed image size is accurate, clear and error-free. When the printing device is calibrated, step calibration pattern can be used for calibration.

[0082] Two-way calibration is the process of adjusting the printing device to ensure that the printed content can be accurately aligned in the horizontal or vertical direction in the positive and negative directions, so as to ensure accurate alignment in two directions, such as left and right directions, during the printing process, thereby optimizing the printing quality and improving the printing effect. When the printing device is calibrated, two-way calibration pattern can be used for calibration.

[0083] Color registration calibration is the color adjustment of the color image or document printed by the printing device, to ensure that different colors of ink can be accurately aligned, thereby improving the printing quality. When the printing device is calibrated, color registration calibration pattern can be used for calibration.

[0084] Pitch calibration refers to the adjustment of the x-axis and y-axis pitch of the multiple printheads of the printer during the printing process, to ensure the accurate alignment of the printed content and the printing quality. When the printing device is calibrated, pitch calibration pattern can be used for calibration.

[0085] Reference Figure 3 , Figure 3 (a) is a step calibration pattern for step calibration of the printing device, or a pitch calibration pattern for y-axis pitch calibration of the printing device. Figure 3 (b) is a two-way calibration pattern for two-way calibration of the printing device, or a color registration calibration pattern for color registration calibration of the printing device, or a pitch calibration pattern for x-axis pitch calibration of the printing device. Among them, the main scale and the copy scale of the color registration calibration pattern are different in color.

[0086] In one embodiment, the calibration patterns of step calibration, two-way calibration, color registration calibration and pitch calibration are the same, such as all being micrometer patterns, and the calibration actions are different when the printing calibration patterns are calibrated.

[0087] Reference Figure 4 , Figure 4 (a) is a schematic diagram of the calibration pattern, Figure 4 (b) and Figure 4 (c) is the calibration pattern actually printed by the printing device.

[0088] The grid spacing of the main ruler and the sub-ruler in the calibration pattern can be determined by DPI (Dots Per Inch). In some embodiments, the main ruler has one grid for every 10 dots, and the sub-ruler has one grid for every 9 dots.

[0089] As an optional embodiment, the calibration method of the printing device further includes: identifying a line missing area in the calibration image; and filling the line missing area. In this embodiment, the line missing area caused by the blocked hole is filled, so as to avoid the error caused by the blocked hole.

[0090] Optionally, the line missing area is filled based on a preset interpolation algorithm, such as a linear interpolation algorithm, a nearest neighbor interpolation algorithm, etc. For example, the missing line in the printing of the main ruler or the sub-ruler is identified, the position of the missing line is determined based on the positions of the adjacent lines, and the missing line is filled. Other ways can also be used to fill the line missing area, such as lengthening the non-missing line to fill the missing area, or copying the adjacent line to the missing area.

[0091] As an optional embodiment, if a preset printing condition is met, the printing device is controlled to print the calibration pattern on the printing medium; wherein the preset printing condition includes at least one of the following: receiving a calibration instruction input by a user in the printing device; receiving a calibration instruction sent by a host computer; the cumulative printing time of the printing device is greater than a preset time threshold; and detecting that the printing device replaces a print head. When the cumulative printing time is long, the printing device is prone to printing deviation, and therefore needs to be calibrated. When it is detected that the printing device replaces the print head, the printing effect may be different under the same control parameters, and therefore needs to be calibrated. In order to improve the flexibility of calibration, when the calibration instruction input by the user in the printing device is received, or the calibration instruction sent by the host computer is received, the printing device is controlled to print the calibration pattern, so as to perform subsequent parameter calibration.

[0092] In step S20, a calibration image is obtained by photographing the calibration pattern.

[0093] Optionally, the calibration image of the calibration pattern is obtained by photographing the calibration pattern by the camera.

[0094] As an optional embodiment, the camera of the printing device is controlled to photograph the calibration pattern to obtain the calibration image, and the printing device can send the calibration image to the host computer. Referring to Figure 1 The camera and the print head are arranged on the print carriage of the printing device, so that the printed calibration image can be obtained in real time, and the convenience of obtaining the calibration image is improved.

[0095] In step S30, actual deviation data between the main ruler and the sub-ruler is identified according to the calibration image.

[0096] Optionally, the actual deviation data between the master ruler and the replica ruler can be recognized in a machine vision based manner. The actual deviation data includes a distance between the zero scale of the master ruler and the zero scale of the replica ruler, which can be an actual moving distance of the print head or the print material.

[0097] In step S40, an offset error of the printing device is calculated according to the actual deviation data and the theoretical deviation data between the master ruler and the replica ruler.

[0098] It is to be noted that the offset error is a difference between the actual deviation data and the theoretical deviation data in the actual printing process of the printing device. The offset error can be caused by various factors, such as wear of mechanical structure, inaccurate control when the print head moves, difference in ink drop landing position, precision of feeding, precision of nozzle of the print head, etc. For example, a step error in controlling the transmission of the print medium.

[0099] The theoretical deviation data between the master ruler and the replica ruler includes a theoretical distance between the zero scale of the master ruler and the zero scale of the replica ruler, which is a theoretical moving distance of the print head or the print medium. The distance can be obtained based on the distance between the zero scale of the master ruler and the zero scale of the replica ruler in the calibration pattern without deviation, which can be pre-stored in the memory. Alternatively, the theoretical deviation data is a preset moving distance of the print medium.

[0100] Optionally, the offset error of the printing device is calculated according to a difference or a ratio of the actual deviation data and the theoretical deviation data between the master ruler and the replica ruler.

[0101] When the difference between the actual deviation data and the theoretical deviation data is greater than a preset difference threshold, it is considered that the printing device has an offset error.

[0102] In step S50, a calibration parameter of the printing device is generated according to the offset error.

[0103] Optionally, the calibration parameter includes a position calibration parameter, wherein the position calibration parameter includes a horizontal offset and a vertical offset, which are used to adjust the position deviation of the print head or the print medium in horizontal and vertical directions. For example, if the offset error in the horizontal direction is 0.2 mm, the horizontal offset in the generated calibration parameter is set to offset 0.2 mm to the right to correct the offset error. For another example, the calibration parameter is calculated according to the offset error and the moving distance, so as to modify the moving distance based on the calibration parameter. Specifically, if the offset error is 0.2 mm and the moving distance is 100 mm, the calibration parameter can be 0.2 / 100=0.002.

[0104] In an optional embodiment, according to the calculated offset error, a corresponding calibration parameter is generated to adjust the X-axis and Y-axis control parameters of the printing device. For example, if the offset error in the X-axis direction is 2mm, a calibration parameter is generated to instruct the printing device to move -2mm in the X-axis direction to compensate for the offset error.

[0105] Optionally, the calibration parameter includes a spacing calibration parameter of the printhead. Optionally, for a double-head printing device, a calibration parameter can also be generated according to the offset error to adjust the relative position control parameters of the two printheads so that they can be correctly aligned during printing.

[0106] The calibration parameter can accurately adjust the control parameters of the printing device so that it can print according to the preset path and position during printing, reduce errors, and improve the accuracy of the printed content. For example, when the calibration parameter is a horizontal offset, the control parameter is adjusted by the calibration parameter, for example, the step distance of the stepper motor, so as to adjust the movement distance of the printing medium to ensure that the position deviation of the printing medium in the horizontal direction is corrected.

[0107] In the printing device, the control parameter is used to control the printing process of the printing device, including but not limited to the step distance of the motor, the printing speed, the temperature, the printing head movement acceleration, the printing head offset correction, etc., which will affect the printing quality of the printing device. According to the calibration parameter, the control parameter of the printing device is calibrated, which improves the printing accuracy of the printing device and improves the calibration efficiency of the printing device.

[0108] As another optional embodiment, the calibration image is sent to the host computer, which is used to identify the actual deviation data between the master ruler and the copy ruler according to the calibration image; according to the actual deviation data and the theoretical deviation data between the master ruler and the copy ruler, the offset error of the printing device is calculated; according to the offset error, the calibration parameter of the printing device is generated, and the calibration parameter is sent to the printing device; the printing device obtains the calibration parameter returned by the host computer, and calibrates the control parameter of the printing device, and the printing device prints based on the calibrated control parameter. Since the computing power of the host computer is superior to that of the printing device, the calculation speed of the offset error and / or the control parameter is improved, and the data processing efficiency is improved.

[0109] In an embodiment, with reference to Figure 5The host computer sends a calibration command to the printing device, and the calibration command includes bidirectional calibration, or step calibration, or color calibration, or pitch calibration, etc. The printing device prints a corresponding calibration pattern. An optical sensor captures the printed calibration pattern to obtain a calibration image. Based on the calibration image and the steps S10 to S50, or the processing of the steps S10 to S50 sent to the host computer, the calibration parameters are obtained. The calibration parameters are written into a calibration description file for subsequent calibration and image printing. The new calibration parameters are used to calibrate the control parameters to print the pattern, and it is verified whether the printed pattern after calibration meets the standard.

[0110] In the technical scheme of the embodiment, according to the calibration instruction, the printing device prints a calibration pattern on the printing medium; a calibration image is obtained; actual deviation data between the master scale and the copy scale is identified according to the calibration image; offset error of the printing device is calculated according to the actual deviation data and theoretical deviation data between the master scale and the copy scale; and calibration parameters of the printing device are generated according to the offset error. The master scale as a reference pattern before the calibration action can provide an explicit contrast reference for the copy scale printed after the calibration action. Through comparison of the actual deviation data and the theoretical deviation data between the master scale and the copy scale of the calibration pattern, the offset error of the printing device can be accurately calculated. The calibration parameters are generated by using the offset error, which can effectively correct the printing position deviation of the printing device, ensure that the print head moves according to the predetermined path or distance, thereby improving the printing precision and accuracy, and realizing automatic calibration of the printing device, reducing manual intervention, and reducing maintenance cost and operation complexity.

[0111] Based on the first embodiment of the present application, in the second embodiment of the present application, the same or similar contents as the above embodiments can be referred to the above introduction, and will not be described in detail. On this basis, please refer to Figure 6 , step S30 includes:

[0112] In step S31, the distance between the zero scale of the master scale and the zero scale of the copy scale is determined according to the calibration image, and the actual deviation data is obtained.

[0113] Optionally, the actual deviation data includes the actual movement distance of the print head or the printing medium. For example, in step calibration, the actual deviation data includes the actual movement distance of the printing medium, and in bidirectional calibration, color calibration and pitch calibration, the actual deviation data includes the actual movement distance of the print head.

[0114] Alternatively, the pixel distance from the zero mark on the main scale to the zero mark on the secondary scale is calculated, and the pixel length corresponding to a known physical length in the calibration image, such as the physical length of the zero mark, is obtained. A scaling factor is determined based on the physical length and the pixel length. The scaling factor S is used to convert the pixel distance between the zero marks to the actual movement distance. Alternatively, the actual deviation data can be directly calculated based on the pixel distance from the zero mark on the main scale to the zero mark on the secondary scale and the intrinsic and extrinsic parameters of the camera.

[0115] In an optional embodiment, a calibration method for a printing device includes: identifying a main scale scale value on the main scale in a calibration image that is before the zero scale of the complex scale and closest to the zero scale of the complex scale; identifying a complex scale scale value in the calibration image where the scales of the complex scale coincide with those of the main scale; and determining a distance between the zero scale of the main scale and the zero scale of the complex scale based on the main scale scale value and the complex scale scale value.

[0116] Optionally, the actual deviation data is determined based on the distance between the main scale graduation value and the main scale unit distance and the distance between the secondary scale graduation value and the secondary scale unit distance. Figure 3 (a) The main scale mark on the main ruler that is before the zero mark on the secondary ruler and is farther from the zero mark on the secondary ruler is the 10th mark on the main ruler. The secondary scale mark on the calibration image where the secondary ruler and the main ruler overlap is the 6th mark on the secondary ruler. Based on the unit distances corresponding to the main and secondary scale marks, for example, one mark on the main ruler corresponds to 10 mm and one mark on the secondary ruler corresponds to 1 mm, the actual deviation data = main scale mark * main scale unit distance + secondary scale mark * secondary scale unit distance = 10*10+6*1 = 106 mm.

[0117] In an optional embodiment, the graduation value of the main scale is the length of multiple ink droplets; the number of ink droplets that differ between the zero scale of the main scale and the zero scale of the complex scale is determined based on the scale values ​​of the main scale and the scale values ​​of the complex scale; and the distance between the zero scale of the main scale and the zero scale of the complex scale is calculated based on the length of each ink droplet and the number of ink droplets that differ.

[0118] Alternatively, as shown in the following formula:

[0119] Distance = length of each ink droplet * number of ink droplets that differ.

[0120] For example, the difference between the zero mark of the main scale and the zero mark of the secondary scale is m ink droplets. Then, the actual deviation data D can be calculated by the following formula:

[0121] D=m×the length of each ink droplet.

[0122] By using ink drop count as the unit of measurement, the accuracy of measurement can be improved, the reliance on personal visual judgment can be reduced, human error can be reduced, and the consistency and reliability of measurement can be improved.

[0123] Wherein, the minimum length or distance of the ink drop point is determined by DPI, for example, if printing at 300 DPI resolution, the length of each ink drop point is 25.4mm / 300≈0.085mm.

[0124] For example, referring to Figure 3 (a), the graduation value represents the length of 10 ink drop points, and there are 106 ink drop points in total. Then, the distance D1 can be calculated by the following formula:

[0125] D1=m1*length of each ink drop point=106*0.085=9.01mm.

[0126] Suppose the number of ink drop points corresponding to the theoretical deviation data is 100, then the distance D2 can be calculated by the following formula:

[0127] D2=m2*length of each ink drop point=100*0.085=8.5mm.

[0128] When the actual deviation data is calculated, the offset error=actual deviation data-theoretical deviation data.

[0129] For example, the graduation value represents the length of 10 ink drop points, the number of ink drop points corresponding to the theoretical deviation data is 100, and the number of ink drop points corresponding to the actual deviation data is 106, and the offset error=(106-100)*0.085=0.51mm.

[0130] For another example, the graduation value represents the length of 10 ink drop points, the number of ink drop points corresponding to the theoretical deviation data is 100, and the corresponding distance D1=9.01mm, the number of ink drop points corresponding to the actual deviation data is 106, and the corresponding distance D2=8.5mm, and the offset error D=D1-D2=9.01-8.5=0.51mm.

[0131] In the technical scheme of the embodiment, the main ruler serves as a reference pattern before the calibration action, can provide a clear comparison reference for the printed copy ruler after the calibration action, by determining the distance between the zero scale of the main ruler in the calibration image and the zero scale of the copy ruler, obtaining the actual deviation data between the main ruler and the copy ruler, obtaining the actual movement distance of the print head or the print medium, improving the accuracy of the actual movement distance measurement, facilitating the calculation of the offset error by comparing the difference between the actual deviation data and the theoretical deviation data, and then updating the control parameters of the printing equipment according to the offset error, to improve the printing precision and quality, help to optimize the printing process, reduce material waste, prolong the service life of the equipment, and improve the production efficiency.

[0132] Based on the first or second embodiment of the present application, in the third embodiment of the present application, the same or similar contents as the above embodiments can be referred to the above introduction, and will not be repeated hereinafter. On this basis, please refer toFigure 7 , after step S50, further comprising:

[0133] Step S60, controlling the print head to re-print the calibration pattern based on the calibration parameter;

[0134] Step S70, obtaining a reference image corresponding to the re-printed calibration pattern;

[0135] Step S80, identifying actual reference deviation data between the master ruler and the copy ruler according to the reference image;

[0136] Step S90, calculating an offset reference error of the printing device according to the actual reference deviation data and theoretical deviation data between the master ruler and the copy ruler;

[0137] Step S100, if the offset reference error is less than a preset error threshold, saving the calibration parameter;

[0138] Step S110, if the offset reference error is greater than the error threshold, generating a calibration parameter again according to the offset reference error, and performing a re-calibration step on the printing device until the offset reference error is less than the preset error threshold.

[0139] It should be noted that the offset reference error is the difference between the actual deviation data of the printing device in the actual printing process and the theoretical deviation data.

[0140] As an optional embodiment, if the offset reference error is equal to the error threshold, the calibration parameter is saved, or a calibration parameter is generated again according to the offset reference error, and a re-calibration step is performed on the printing device until the offset reference error is less than the preset error threshold.

[0141] Optionally, the camera of the printing device is controlled to capture the calibration pattern to obtain the reference image, and the reference image includes the calibration pattern. The printing effect of the reference image is better than that of the calibration image, but whether the current printing effect meets the printing standard needs to be further determined.

[0142] As an optional embodiment, identifying the actual reference deviation data between the master ruler and the copy ruler according to the reference image includes: determining the distance between the zero scale of the master ruler and the zero scale of the copy ruler according to the calibration image to obtain the actual reference deviation data between the master ruler and the copy ruler.

[0143] Optionally, the actual reference deviation data includes the actual movement distance of the print head or the printing medium. For example, in the step calibration, the actual reference deviation data includes the actual movement distance of the printing medium, and in the bidirectional calibration, the color registration calibration and the pitch calibration, the actual reference deviation data includes the actual movement distance of the print head.

[0144] Further, a main ruler scale value before the zero scale of the main ruler and the distance from the zero scale of the main ruler are identified in the reference image; a scale value of the auxiliary ruler scale that coincides with the scale of the main ruler in the reference image is identified; and actual reference deviation data is determined according to the main ruler scale value and the auxiliary ruler scale value.

[0145] In an optional embodiment, the graduation value of the main ruler is the length of a plurality of ink drop points; and the step of determining the actual reference deviation data according to the main ruler scale value and the auxiliary ruler scale value comprises: determining the number of ink drop points that differ between the zero scale of the main ruler and the zero scale of the auxiliary ruler according to the main ruler scale value and the auxiliary ruler scale value; and calculating the actual reference deviation data between the zero scale of the main ruler and the zero scale of the auxiliary ruler according to the length of each ink drop point and the number of ink drop points that differ.

[0146] Optionally, an offset reference error of the printing device is calculated according to the difference or ratio of the actual reference deviation data and the theoretical deviation data between the main ruler and the auxiliary ruler.

[0147] In the technical scheme of the embodiment, by reprinting the calibration pattern and obtaining the reference image, it can be ensured that the measurement result of the control system is as close as possible to the theoretical value, thereby improving the stability and efficiency of the entire process. Through calibration, it can be ensured that the printed lines, graphic contours, and character edges are continuous and smooth, and the pattern content is not misaligned, thereby improving the printing quality.

[0148] Based on any one of the first to third embodiments, in the fourth embodiment, the same or similar contents as the above embodiments can be referred to the above description, and will not be described hereinafter. On this basis, please refer to Figure 8 If the calibration instruction indicates step-by-step calibration, step S10 comprises the following steps S11 to S13.

[0149] Step S11, controlling the print head of the printing device to print the main ruler;

[0150] Step S12, after printing the main ruler, performing a first calibration action, the first calibration action comprising: controlling the printing medium to move a preset distance along a first direction, and moving the print head along a second direction, so that the print head is located on one side of the main ruler in the second direction, the second direction being perpendicular to the first direction;

[0151] Step S13, controlling the print head to print the auxiliary ruler.

[0152] It is to be noted that when the calibration instruction indicates step calibration, before the first calibration action, the print head of the printing device is controlled to print a main ruler. After the main ruler is printed, the first calibration action is performed, i.e. the feeding module is controlled to feed the printing medium by a preset distance in a first direction, and the print head is moved in a second direction so that the print head is located on one side of the main ruler in the second direction, the second direction being perpendicular to the first direction. For example, the first direction is the x-axis direction, and the second direction is the y-axis direction. After the first calibration action, the print head is controlled to print a duplicate ruler.

[0153] In some embodiments, with reference to Figure 9 , if the calibration instruction indicates bidirectional calibration or pitch calibration or color calibration, step S10 comprises steps S14 to S16.

[0154] Step S14, the print head is moved from the starting position to a preset position in the positive direction of the second direction, and the print head is controlled to print the main ruler;

[0155] Step S15, after the main ruler is printed, a second calibration action is performed, the second calibration action comprising: moving the print head to an end position in the positive direction of the first direction; moving the print head from the end position to the preset position in the negative direction of the first direction and moving the printing medium in the first direction so that the print head is located on one side of the main ruler in the first direction;

[0156] Step S16, the print head is controlled to print the duplicate ruler.

[0157] It is to be noted that when the calibration instruction indicates bidirectional calibration or pitch calibration or color calibration, before the second calibration action, the print head is moved from the starting position to a preset position in the positive direction of the second direction, and the print head is controlled to print the main ruler. After the main ruler is printed, the print head is moved to an end position in the positive direction of the first direction; the second calibration action is performed, the print head is moved from the end position to the preset position in the negative direction of the first direction and the printing medium is moved in the first direction so that the print head is located on one side of the main ruler in the first direction; after the calibration action, the print head is controlled to print the duplicate ruler. For example, the first direction is the x-axis direction, and the second direction is the y-axis direction.

[0158] When the calibration instruction indicates color calibration, the printing colors of the master ruler and the duplicate ruler are different, before the calibration action, the printhead is moved from the starting position to the preset position in the positive direction of the second direction, and the printhead is controlled to print the master ruler. After printing the master ruler, the printhead is moved to the end position in the positive direction of the first direction, the calibration action is performed, the printhead is moved from the end position to the preset position in the negative direction of the first direction and the printing medium is moved, the printing medium is moved in the first direction so that the printhead is located on one side of the master ruler in the first direction, and the duplicate ruler is printed after the calibration action. For example, the first direction is the x-axis direction, and the second direction is the y-axis direction.

[0159] In the technical scheme of the embodiment, different calibration actions are performed through different calibration instructions, the first calibration action includes the moving direction of the printhead and the moving direction and distance of the printing medium, the second calibration action includes the patterns of the master ruler and the duplicate ruler printed before and after the calibration action, the calibration patterns are printed on the printing medium by the printing device, the offset error is calculated by comparing the difference between the actual deviation data and the theoretical deviation data, and then the calibration parameters of the printing device are generated according to the offset error, so that the printing precision and quality are improved, the printing process is optimized, material waste is reduced, the service life of the device is prolonged, and the production efficiency is improved.

[0160] It should be noted that the above examples are only used to understand the present application and do not constitute a limitation on the calibration method of the printing device of the present application. More forms of simple transformation based on the technical concept are within the protection scope of the present application.

[0161] The present application provides an electronic device, comprising: at least one processor; and a memory in communication connection with the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the calibration method of the printing device in the above-mentioned embodiment one.

[0162] Reference will now be made to Figure 10 which shows a structural schematic diagram of an electronic device suitable for implementing the embodiments of the present application. The electronic device in the embodiments of the present application can include but is not limited to mobile terminals such as mobile phones, notebook computers, PAD (Portable Application Description: tablet computers), PMP (Portable Media Player: portable multimedia players) and the like, and fixed terminals such as digital TVs, desktop computers and the like. Figure 10 The electronic device shown is only an example and should not limit the functions and use range of the embodiments of the present application. Among them, the electronic device can be the host computer or the printing device described in the above-mentioned embodiments.

[0163] As shown in Figure 10 The electronic device can include a processing device 1001 (e.g., a central processing unit, a graphics processing unit, etc.) that can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM) 1002 or a program loaded from a storage device 1003 into a random access memory (RAM) 1004. Various programs and data required for operation of the electronic device are also stored in the RAM 1004. The processing device 1001, the ROM 1002, and the RAM 1004 are connected to each other through a bus 1005. An input / output (I / O) interface 1006 is also connected to the bus. In general, the following systems can be connected to the I / O interface 1006: an input device 1007 including, for example, a touch screen, a touch pad, a keyboard, a mouse, an image sensor, a microphone, an accelerometer, a gyroscope, etc.; an output device 1008 including, for example, a liquid crystal display (LCD), a speaker, a vibrator, etc.; the storage device 1003 including, for example, a magnetic tape, a hard disk, etc.; and a communication device 1009. The communication device 1009 can allow the electronic device to communicate wirelessly or by wire with other devices to exchange data. Although the electronic device having various systems is shown in the figure, it should be understood that all of the systems shown are not required to be implemented or possessed. More or less systems can be alternatively implemented or possessed.

[0164] In particular, the processes described above with reference to the flowcharts can be implemented as a computer software program according to embodiments of the present disclosure. For example, embodiments of the present disclosure include a computer program product comprising a computer program carried on a computer readable medium, the computer program containing program code for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network by a communication device, or installed from the storage device 1003, or installed from the ROM 1002. When the computer program is executed by the processing device 1001, the above-mentioned functions defined in the methods of embodiments of the present disclosure are performed.

[0165] The electronic device provided by the present application adopts the calibration method of the printing device in the above-mentioned embodiments, which can solve the technical problem of poor calibration effect of control parameters. Compared with the prior art, the electronic device provided by the present application has the same beneficial effects as the calibration method of the printing device provided by the above-mentioned embodiments, and the other technical features in the electronic device are the same as the features disclosed in the previous embodiment method, which will not be repeated here.

[0166] It should be understood that various parts of the present application can be realized in hardware, software, firmware or a combination thereof. In the description of the above embodiments, specific features, structures, materials or characteristics can be combined in any one or more embodiments or examples in a suitable manner.

[0167] The above describes only the specific implementation of the present application, but the protection scope of the present application is not limited thereto, any person skilled in the art can easily think of changes or replacements within the technical range disclosed by the present application, which should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

[0168] With reference to Figure 11 The present application also proposes a printing device 200, comprising:

[0169] A communication component 240 is configured to receive a calibration file, wherein the calibration file comprises calibration parameters obtained based on the calibration method of the printing device according to any one of the above embodiments.

[0170] A print head 211 is configured to print a pattern.

[0171] A processor 230 is configured to control the print head to print the pattern based on the calibration file.

[0172] The printing device 200 can be a DTF (Direct to film) printing device or a common household inkjet printing device. The printing device 200 in the present embodiment can refer to the description of the printing device in the above embodiments, which will not be repeated here. In some embodiments, the processor 230 can control the movement of the print head and the movement of the printing medium in addition to controlling the print head to print the pattern.

[0173] In addition, with reference to Figure 12 The present application also proposes a printing system 1000, comprising a host computer 100 and a printing device 200, wherein the host computer 100 is in communication connection with the printing device 200.

[0174] The printing device 200 is configured to print a calibration pattern based on a calibration instruction.

[0175] The host computer 100 is configured to: issue the calibration instruction to the printing device 200, and obtain calibration parameters based on the calibration method of the printing device according to the above embodiments.

[0176] The printing device 200 is provided with a processor, which is in communication connection with the upper computer. For example, the processor is an MCU (Microcontroller Unit) or a CPU (Central Processing Unit), or an FPGA, etc.

[0177] The present application provides a computer readable storage medium having stored thereon computer readable program instructions (i.e., a computer program) for performing the calibration method of the printing device in the above embodiment.

[0178] The computer readable storage medium provided by the present application may, for example, be a U disk, but is not limited to an electric, magnetic, optical, electromagnetic, infrared, or semiconductor system, system, or device, or any combination of the above. More specific examples of the computer readable storage medium can include, but are not limited to, an electric connection with one or more conductive wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In the present embodiment, the computer readable storage medium can be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, system, or device. The program code contained on the computer readable storage medium can be transmitted by any appropriate medium, including but not limited to an electric wire, an optical cable, an RF (Radio Frequency), etc., or any suitable combination of the above.

[0179] The above computer readable storage medium can be included in an electronic device; or can exist separately without being assembled into an electronic device.

[0180] The above computer readable storage medium carries one or more programs, which, when executed by the electronic device, cause the electronic device to: by calibrating the printing device and adjusting the control parameters, ensure that the print head moves according to the predetermined path or distance, reduce the printing deviation, thereby improve the accuracy of the printed image, and by automatic calibration, reduce manual intervention, reduce maintenance cost and operation complexity.

[0181] Computer program code for carrying out operations of the present application can be written in any combination of one or more programming languages, including an object oriented programming language such as Java, Smalltalk, C++ or the like and conventional procedural programming languages, such as the "C" programming language or similar programming languages. The program code can execute entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer or entirely on the remote computer or server. In the latter scenario, the remote computer can be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or the connection can be made to an external computer (for example, through the Internet using an Internet Service Provider).

[0182] The flow diagrams and the block diagrams in the drawings are illustrations of architectures, functionalities, and operations of possible implementations of systems, methods, and computer program products according to various embodiments of present application. In this regard, each block in the flow diagrams or block diagrams can represent a module, a procedure, or a part of code, which comprises one or more executable instructions for implementing the specified logical functions. It should also be noted that in some alternative implementations, the functions noted in the blocks can occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently or the blocks may

[0183] The modules involved in the embodiments of the present application can be implemented in the form of software or in the form of hardware. Among them, the name of the module does not constitute a limitation to the unit itself in some cases.

[0184] The readable storage medium provided by the present application is a computer readable storage medium, which stores computer readable program instructions (i.e. computer program) for executing the calibration method of the printing device, and can solve the technical problem of poor calibration effect of control parameters. Compared with the prior art, the computer readable storage medium provided by the present application has the same beneficial effects as the calibration method of the printing device provided by the above-mentioned embodiments, which will not be repeated here.

[0185] The application also provides a computer program product comprising a computer program which, when executed by a processor, implements the steps of the calibration method of the printing device as described above.

[0186] The computer program product provided by the application can solve the technical problem of poor calibration effect of the control parameter. Compared with the prior art, the beneficial effects of the computer program product provided by the application are the same as those of the calibration method of the printing device provided by the above-mentioned embodiments, and are not described here.

[0187] The above only describes some embodiments of the application, and does not limit the patent scope of the application. Any equivalent structural transformation, direct / indirect application in other related technical fields, or direct / indirect application in other related technical fields based on the technical concept of the application and the content of the specification and drawings are included in the patent protection scope of the application.

Claims

1. A calibration method of a printing apparatus, characterized by, The method comprises: controlling the printing device to print a calibration pattern on a printing medium according to a calibration instruction, the calibration pattern comprising a primary scale and a secondary scale, the primary scale having a different scale value from the secondary scale, the primary scale and the secondary scale being respectively a pattern printed before and after a calibration action; obtaining a calibration image, the calibration image being obtained by photographing the calibration pattern; identifying actual deviation data between the primary scale and the secondary scale according to the calibration image; calculating an offset error of the printing device according to the actual deviation data and theoretical deviation data between the primary scale and the secondary scale; generating a calibration parameter of the printing device according to the offset error; controlling a print head of the printing device to re-print the calibration pattern based on the calibration parameter; obtaining a reference image corresponding to the re-printed calibration pattern, the reference image being obtained by photographing the re-printed calibration pattern; identifying actual reference deviation data between the primary scale and the secondary scale according to the reference image; calculating an offset reference error of the printing device according to the actual reference deviation data and the theoretical deviation data between the primary scale and the secondary scale; if the offset reference error is less than a preset error threshold, saving the calibration parameter; if the offset reference error is greater than the error threshold, generating a new calibration parameter again according to the offset reference error, and performing the step of recalibrating the printing device until the offset reference error is less than the preset error threshold.

2. The method of claim 1, wherein, The step of identifying actual deviation data between the primary scale and the secondary scale according to the calibration image comprises: determining a distance between a zero scale of the primary scale and a zero scale of the secondary scale according to the calibration image to obtain the actual deviation data.

3. The method of claim 2, wherein, The step of determining a distance between a zero scale of the primary scale and a zero scale of the secondary scale according to the calibration image comprises: identifying a primary scale value on the primary scale in the calibration image before the zero scale of the secondary scale and closest to the zero scale of the secondary scale; identifying a secondary scale value of the secondary scale in the calibration image coinciding with a scale of the primary scale; determining the distance between the zero scale of the primary scale and the zero scale of the secondary scale according to the primary scale value and the secondary scale value.

4. The method of claim 3, wherein, The scale value of the primary scale is a length of a plurality of ink drop points; the step of determining the distance between the zero scale of the primary scale and the zero scale of the secondary scale according to the primary scale value and the secondary scale value comprises: determining a number of ink drop points different between the zero scale of the primary scale and the zero scale of the secondary scale according to the primary scale value and the secondary scale value; calculating the distance between the zero scale of the primary scale and the zero scale of the secondary scale according to the length of each ink drop point and the number of ink drop points different.

5. The method of claim 1, wherein, Before the step of identifying actual deviation data between the primary scale and the secondary scale according to the calibration image, the method further comprises: identifying a line missing area in the calibration image; performing a filling processing on the line missing area.

6. The method according to any one of claims 1 to 5, characterized in that, If the calibration instruction indicates a step calibration, the step of controlling the printing device to print a calibration pattern on a printing medium comprises: controlling the print head of the printing device to print the main ruler; after printing the main ruler, performing a first calibration action, the first calibration action comprising: controlling the printing medium to move a preset distance along a first direction, and moving the print head along a second direction to make the print head located on one side of the main ruler in the second direction, the second direction being perpendicular to the first direction; controlling the print head to print the copy ruler; and / or, if the calibration instruction indicates bidirectional calibration, or pitch calibration or color calibration, the step of controlling the printing device to print the calibration pattern on the printing medium comprises: moving the print head from the starting position to a preset position along the positive direction of the second direction, and controlling the print head to print the main ruler; after printing the main ruler, performing a second calibration action, the second calibration action comprising: moving the print head to an end position along the positive direction of the first direction; moving the print head from the end position to the preset position along the negative direction of the first direction and moving the printing medium along the first direction to make the print head located on one side of the main ruler in the first direction, the second direction being perpendicular to the first direction; controlling the print head to print the copy ruler.

7. The method according to any one of claims 1 to 5, wherein, The step of obtaining the calibration image comprises: controlling the camera of the printing device to capture the calibration pattern to obtain the calibration image.

8. An electronic device, comprising: The electronic device comprises a memory, a processor, and a computer program stored on the memory and executable on the processor, the computer program being configured to implement the steps of the calibration method of the printing device according to any one of claims 1 to 7.

9. A printing device, characterized by, comprises: a communication component configured to receive a calibration file, the calibration file comprising calibration parameters obtained based on the calibration method of the printing device according to any one of claims 1 to 7; a print head configured to print a pattern; a processor configured to control the print head to print the pattern based on the calibration file.

10. A printing system, characterized by, The printing system comprises a host computer and a printing device, and the host computer is in communication connection with the printing device; the printing device is configured to print a calibration pattern based on a calibration instruction; the host computer is configured to: issue the calibration instruction to the printing device, and obtain calibration parameters based on the calibration method of the printing device according to any one of claims 1 to 7.

11. A computer readable storage medium, characterized in that, The storage medium has a computer program stored thereon, and the computer program is executed by the processor to implement the steps of the calibration method of the printing device according to any one of claims 1 to 7.

Images