Printing methods, apparatus and equipment for eliminating color differences in images

Abstract

This invention belongs to the field of printing technology and provides a printing method, apparatus, and device for eliminating image color difference. The printing method for eliminating image color difference includes: S1: obtaining the ink volume required for printing the image to be printed using the original printing precision as a first printing ink volume; S2: obtaining the ink volume required for printing the image to be printed using printhead precision as a second printing ink volume; S3: obtaining the position information of the nozzles in the uniform ink color area; S4: determining the step distance of the printhead after one scan printing based on the position information and the ink volume difference; S5: controlling at least a portion of the nozzles in the uniform ink color area of ​​the printhead to print according to the printhead precision, while the remaining nozzles print according to the dot matrix position printed using the printhead precision. This invention also includes an apparatus and device for performing the above method. This invention can eliminate image color difference caused by differences in nozzles in the printhead.

Description

[0001] This application is a divisional application of the invention patent application filed on June 8, 2021, entitled "Printing method, apparatus, device and storage medium for eliminating printhead color difference", with application number: 202110638055.5. Technical Field

[0002] This invention relates to the field of inkjet printing technology, and in particular to a printing method, apparatus, and device for eliminating color differences in images. Background Technology

[0003] Currently, in the operation of industrial inkjet printers, the printer head ejects ink droplets onto the printing medium to form images or text. For example... Figure 1a As shown, to achieve high-precision and high-efficiency printing, inkjet printheads typically consist of multiple rows of nozzles. However, due to manufacturing differences in each nozzle, images printed from a single printhead may exhibit color variations. Figure 1c As shown; at the same time, in order to increase the print height that the printhead can print in a single scan, printhead manufacturers have designed, as shown... Figure 1b The nozzle shown, Figure 1b Each printhead consists of four rows of nozzles (1, 2, 3, 4). Due to manufacturing differences in each nozzle, the printed images from each row of nozzles exhibit color variations. Current technology adjusts printhead color differences through pressure regulation, but this only allows for overall pressure adjustment of one printhead or one row of nozzles, not for individual nozzles or several nozzles. The inconsistent characteristics of some nozzles mean that the problem of color differences in the printed images still exists. Summary of the Invention

[0004] In view of this, embodiments of the present invention provide a printing method, apparatus, and device for eliminating color differences in images, in order to solve the technical problem of color differences in printed images caused by differences in the various nozzles in the printhead in the prior art.

[0005] The technical solution adopted in this invention is:

[0006] In a first aspect, the present invention provides a printing method for eliminating color differences in images, the method comprising:

[0007] S1: Obtain the amount of ink required to print the image to be printed using the original printing precision as the first printing ink amount;

[0008] S2: Obtain the amount of ink required to print the image to be printed using the printhead precision as the second printing ink amount;

[0009] S3: Obtain the position information of the nozzles in the part of the printhead where the ink color is uniform;

[0010] S4: Determine the step distance of the printhead after one scan and print based on the position information and the ink volume difference between the first and second printing ink volumes;

[0011] S5: Based on the stepping distance and the position information, control the nozzles of at least a portion of the inkjet color uniform part of the printhead to print according to the printhead precision, and the remaining nozzles to print according to the dot matrix position printed with printhead precision.

[0012] Preferably, step S3: obtaining the position information of the nozzles in the uniform ink color portion of the printhead further includes the following steps;

[0013] S31: Control the printhead to print the test pattern and then scan the printed test pattern;

[0014] S32: Obtain the location of color difference in each printhead by scanning the test pattern obtained from the printout;

[0015] Preferably, the nozzle precision is less than the original printing precision of the image to be printed.

[0016] Preferably, step S4: determining the step distance after one scan and print based on the position information and the ink volume difference between the first and second printing ink volumes includes the following steps:

[0017] S41: Obtain the ink volume difference Vd between the second printing ink volume and the first printing ink volume;

[0018] S42: Obtain the initial step distance based on the printhead length, the second printing ink volume, and the ink volume difference;

[0019] S43: Determine the length L2 of the uniform inkjet color section in the printhead based on the position information of the nozzles in the uniform inkjet color section;

[0020] S44: Compare the initial step distance D1 with the length L2 of the uniform inkjet color portion in the printhead;

[0021] S45: Determine the step distance after one scan and printing based on the comparison results.

[0022] Preferably, in step S42: obtaining the initial step distance based on the printhead length, the second printing ink volume, and the ink volume difference, the initial step distance is calculated according to the formula D1=1 / (Vd / Vr+1)*L1, where L1 is the printhead length, D1 is the initial step distance, and Vr is the second printing ink volume.

[0023] Preferably, step S45: determining the step distance after one scan and printing by the printhead based on the comparison results includes the following steps:

[0024] S451: If the initial step distance D1 is less than or equal to the length L2 of the uniform ink color portion in the printhead, then the initial step distance D1 is used as the step distance after one scan and printing of the printhead.

[0025] S452: If the initial step distance D1 is greater than the length L2 of the uniform ink color portion in the printhead, then the length L2 of the uniform ink color portion in the printhead is used as the step distance after one scan and print.

[0026] Preferably, if the initial step distance D1 is less than or equal to the length L2 of the uniform ink color portion in the printhead, then step S5 includes the following steps:

[0027] S51: Select at least a portion of the nozzles from the nozzles in the uniform inkjet color area as the first group of nozzles based on the step distance and the position information, and select the remaining nozzles of the printhead as the second group of nozzles.

[0028] S52: Control the first group of nozzles to print according to the printhead precision;

[0029] S53: Obtain the printing data of the first group of nozzles as the first printing data;

[0030] S54: Control the second group of nozzles to repeat printing according to the first printing data.

[0031] Preferably, the ink droplets ejected by the printing device include a first type of ink droplet, a second type of ink droplet, and a third type of ink droplet, wherein the volume of the first type of ink droplet is larger than the volume of the second type of ink droplet, and the volume of the second type of ink droplet is larger than the volume of the third type of ink droplet. If the initial step distance D1 is less than or equal to the length L2 of the uniform ink color portion in the printhead, step S5 includes the following steps:

[0032] S501: Select at least a portion of the nozzles from the nozzles in the uniform inkjet color area as a first group of nozzles based on the step distance and the position information, and select the remaining nozzles of the printhead as a second group of nozzles.

[0033] S502: Control the first group of nozzles to print according to the printhead precision;

[0034] S503: Obtain the printing data of the first group of nozzles as the first printing data;

[0035] S504: After adjusting the data in the first print data that uses the third type of ink droplet to no ink droplet data, the first intermediate print data is obtained;

[0036] S505: Obtain the ink volume printed by the second group of nozzles using the first intermediate printing data as the third printing ink volume;

[0037] S506: Compare the difference between the third printing ink volume and the ink volume;

[0038] S507: Obtain second printing data based on the comparison result between the first intermediate printing data and the third printing ink volume and the ink volume difference;

[0039] S508: Control the second group of nozzles to print according to the second printing data;

[0040] If the initial step distance D1 is greater than the length L2 of the uniform ink color portion in the printhead, step S5 includes the following steps:

[0041] S510: Select the nozzles in the area with uniform inkjet color as the third group of nozzles based on the position information, and select the remaining nozzles of the printhead as the remaining nozzles as the fourth group of nozzles.

[0042] S520: Controls the third group of nozzles to print according to the printhead precision;

[0043] S530: Obtain the printing data of the third group of nozzles as the third printing data;

[0044] S540: After adjusting the data in the third print data that uses the third type of ink droplet to data that does not produce ink, the second intermediate print data is obtained;

[0045] S550: Obtain the ink volume printed by the second group of nozzles using the second intermediate printing data as the fourth printing ink volume;

[0046] S560: Compare the fourth printing ink volume with the difference in ink volume;

[0047] S570: Obtain third printing data based on the comparison result between the second intermediate printing data and the fourth printing ink volume and the ink volume difference;

[0048] S580: Controls the fourth group of nozzles to print according to the third printing data.

[0049] In a second aspect, the present invention also provides a printing apparatus for eliminating image color differences, the apparatus comprising:

[0050] The first printing ink volume acquisition module is used to acquire the amount of ink required to print the image to be printed using the original printing precision as the first printing ink volume.

[0051] The second printing ink volume acquisition module is used to acquire the amount of ink required for printing the image to be printed using the nozzle precision as the second printing ink volume.

[0052] A position information acquisition module, wherein the position information acquisition module is used to acquire the position information of the nozzles in the uniform ink color part of the printhead;

[0053] The step distance determination module, wherein the step distance acquisition module is used to determine the step distance after one scan and printing by the printhead based on the position information and the ink volume difference between the first printing ink volume and the second printing ink volume;

[0054] The control module is used to control at least a portion of the nozzles in the printhead with uniform ink color to print according to the printhead precision, based on the step distance and the position information, while the remaining nozzles print according to the dot matrix position printed with printhead precision.

[0055] Thirdly, the present invention also provides a printing apparatus for eliminating image color difference, comprising: at least one processor, at least one memory, and computer program instructions stored in the memory, which implement the method described in the first aspect when executed by the processor.

[0056] Beneficial Effects: The printing method, apparatus, and device for eliminating image color differences of the present invention divides the printhead into a first printhead that prints according to printhead precision and a second printhead that accumulates ink. The present invention utilizes nozzles in the uniformly colored portion of the printhead to print according to printhead precision, while the remaining nozzles repeatedly print according to the dot matrix positions printed with printhead precision. This ensures image detail and eliminates the defect of uneven color printing caused by inconsistent nozzles within the printhead, while maintaining the same amount of ink printed. Because printing with printhead precision avoids situations where the paper feed distance is a small multiple of the aperture spacing, it can prevent printing progress misalignment caused by machine paper feed errors, printhead installation errors, or machine vibration errors. Furthermore, the present invention utilizes a portion of the nozzles in the printhead to print according to printhead precision, combined with the remaining nozzles repeatedly printing at the same positions to achieve the ink volume required for the original printing precision, thus significantly improving the uniformity of the printed image. Attached Figure Description

[0057] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the embodiments of the present invention will be briefly introduced below. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort, and these are all within the protection scope of the present invention.

[0058] Figure 1a This is a schematic diagram of the printer printhead structure;

[0059] Figure 1b This is a schematic diagram of a printer printhead composed of four rows of small nozzles.

[0060] Figure 1c This is a print test pattern used to obtain printhead color difference information;

[0061] Figure 2This is a flowchart of the printing method for eliminating image color difference according to the present invention;

[0062] Figure 3 A flowchart of the method for determining the step distance according to the present invention;

[0063] Figure 4 This is a schematic diagram showing the nozzle length and nozzle arrangement of the present invention;

[0064] Figure 5 This is a flowchart of the first method for controlling the printhead to perform printing according to the present invention;

[0065] Figure 6 This is a flowchart of the second method for controlling the printhead to perform printing according to the present invention;

[0066] Figure 7 This is a schematic diagram showing the ink output from the printhead during precision printing using the present invention.

[0067] Figure 8 This is a schematic diagram illustrating the adjustment of ink output from the printhead according to the present invention;

[0068] Figure 9 This is a schematic diagram illustrating another way to adjust the ink output from the printhead according to the present invention;

[0069] Figure 10 This is a flowchart of the third method for controlling the printhead to perform printing according to the present invention;

[0070] Figure 11 This is a schematic diagram of the multi-pass printing process using nozzles with a uniform initial portion in this invention.

[0071] Figure 12 This is a schematic diagram of the printing apparatus for eliminating color difference in images according to the present invention.

[0072] Figure 13 This is a schematic diagram of the printing device for eliminating image color difference according to the present invention. Detailed Implementation

[0073] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. In the description of the present invention, it should be understood that the terms "center," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, the element defined by the phrase "comprising..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element. Where there is no conflict, embodiments of the present invention and the various features thereof can be combined with each other, all of which are within the scope of protection of the present invention.

[0074] Example 1

[0075] like Figure 2 As shown in the figure, an embodiment of the present invention discloses a printing method for eliminating image color difference, the method comprising:

[0076] S1: Obtain the amount of ink required to print the image to be printed using the original printing precision as the first printing ink amount;

[0077] This embodiment uses the amount of ink ejected when printing an image with the original printing precision as a reference standard. The specific method for obtaining the first printing ink amount is as follows:

[0078] S11: Obtain the volume of various types of ink droplets from the printing device;

[0079] In this embodiment, the types are classified according to the volume of ink droplets. Droplets of the same volume belong to one type, while droplets of different volumes belong to different types. By controlling the drive waveform of the printhead, the printhead of the printing device can eject multiple types of ink droplets. For example, some printing devices can eject a first type of ink droplet (large droplet), a second type of ink droplet (medium droplet), and a third type of ink droplet (small droplet). The volume of the first type of ink droplet is larger than that of the second type, and the volume of the second type of ink droplet is larger than that of the third type. In this embodiment, the number of droplet types, k, can be a positive integer greater than or equal to 2, meaning the printhead can eject at least two different types of ink droplets.

[0080] S12: Obtain the number of each type of ink droplets when printing the image to be printed using the original printing precision;

[0081] For example, if the printing device can eject the first type of ink droplet, the second type of ink droplet, and the third type of ink droplet mentioned above, then in this step, we find the number N1 of the first type of ink droplet ejected by the printhead, the number N2 of the second type of ink droplet ejected by the printhead, and the number N3 of the third type of ink droplet ejected by the printhead when printing at the original printing precision.

[0082] S13: Calculate the first printing ink volume based on the volume of each type of ink droplet and the number of each type of ink droplet.

[0083] The specific calculation method is to multiply the volume of each type of ink droplet by the quantity of that type of ink droplet to obtain the printing ink volume of each type of ink droplet, and then add the printing ink volumes of all types of ink droplets to obtain the first printing ink volume. Taking the printhead ejecting three different volumes of ink droplets as an example, the method for calculating the first printing ink droplet can be: M1 = V1 × N1 + V2 × N2 + V3 × N3, where M1 is the first printing ink volume, V1 is the volume of the first type of ink droplet, V2 is the volume of the second type of ink droplet, and V3 is the volume of the third type of ink droplet.

[0084] S2: Obtain the amount of ink required to print the image to be printed using the printhead precision as the second printing ink amount;

[0085] The printhead resolution is lower than the original printing resolution of the image to be printed. For example, if the original printing resolution is 720 DPI and the printhead resolution is 360 DPI, it is understood that the printhead resolution and the original printing resolution can be other values, as long as the printhead resolution is lower than the original printing resolution. Because the printhead resolution is lower than the original printing resolution, the amount of ink required when printing with the printhead resolution is less than the amount of ink required when printing with the original resolution. The specific steps for obtaining the second printing ink volume are as follows:

[0086] S21: Obtain the volume of various types of ink droplets from the printing device;

[0087] S22: Obtain the number of each type of ink droplet printed using printhead precision;

[0088] For example, when printing according to the printhead progress, three types of ink droplets need to be ejected: the first type, the second type, and the third type. In this step, we need to find the number of the first type of ink droplet ejected by the printhead, the number of the second type of ink droplet ejected by the printhead, and the number of the third type of ink droplet ejected by the printhead when printing with printhead precision.

[0089] S23: Calculate the second printing ink volume based on the volume of each type of ink droplet and the number of each type of ink droplet.

[0090] The specific calculation method is to multiply the volume of each type of ink droplet by the number of ink droplets of that type to obtain the printing ink volume of each type of ink droplet, and then add the printing ink volumes of all types of ink droplets to obtain the second printing ink volume.

[0091] S3: Obtain the position information of the nozzles in the part of the printhead where the ink color is uniform;

[0092] like Figure 1c As shown, although the printhead as a whole may exhibit uneven inkjet color, certain areas within the printhead will contain nozzles with uniform inkjet color (as shown in area A1 in the figure). Therefore, the nozzles with uniform inkjet color mentioned in this step refer to the area containing several consecutive nozzles with uniform inkjet color within the printhead. The position information of the nozzles located in the aforementioned area can be represented by the nozzle's serial number within the printhead, for example... Figure 4 In the diagram, the position of the fourth nozzle along the length of the nozzle can be represented by the number 4.

[0093] One method for obtaining nozzle position information in areas of uniform inkjet color can be achieved by creating a test pattern. Specifically, this involves controlling the printhead to print a test pattern (such as...). Figure 1c (As shown), then by scanning the printed test image, the location and extent of color difference for each printhead are obtained.

[0094] S4: Determine the step distance after one scan and print by the printhead based on the position information and the ink volume difference between the first and second printing ink volumes.

[0095] Reciprocating scanning printing, also known as multi-pass scanning printing, utilizes the alternating scanning and stepping directions of the printhead to interpolate each unit of the image to be printed multiple times. The scanning direction is perpendicular to the nozzle alignment direction, while the stepping direction is parallel to the nozzle alignment direction. In multi-pass scanning printing, after completing one scan along the scanning direction, the printhead moves a certain distance relative to the printing medium along the stepping direction before performing the next scan. This distance is called the stepping distance.

[0096] In multi-pass scanning printing, each cell needs to be covered multiple times. For example, in 2-pass scanning printing, each cell needs to be covered twice to complete the printing of a unit area; in 3-pass scanning printing, it needs to be covered three times to complete the printing of a unit area; and in 4-pass scanning printing, it needs to be covered four times to complete the printing of a unit area.

[0097] S4, which determines the step distance after one scan and print based on the position information and the ink volume difference between the first and second printing ink volumes, further includes the following steps:

[0098] S41: Obtain the ink volume difference Vd between the second printing ink volume and the first printing ink volume;

[0099] The method for calculating the ink volume difference is: Vd = M1 - M2, where M1 is the first printing ink volume and M2 is the second printing ink volume.

[0100] S42: Calculate the initial step distance according to the formula D1=1 / (Vd / Vr+1)*L1, where L1 is the printhead length, D1 is the initial step distance, and Vr is the second printing ink volume;

[0101] like Figure 4 As shown, the length of the nozzle refers to the length along the nozzle arrangement direction. Figure 4 The x-direction (the direction perpendicular to the nozzle scanning direction) Figure 10 The distance from the center of the first nozzle of the nozzle (in the y-direction) to the center of the last nozzle of the nozzle is, for example... Figure 4 If the distance between two adjacent nozzles is d, then the length of a nozzle with 10 nozzles is 9d. For ease of calculation, the nozzle length can also be expressed as the number of nozzles in the nozzle arrangement direction. For example, the aforementioned nozzle with a length of 9d (corresponding to 10 nozzles) can also be expressed as a nozzle with a length of 9 (corresponding to 10 nozzles), where the number represents the number of nozzles in the nozzle arrangement direction.

[0102] S43: Determine the length L2 of the uniform inkjet color section in the printhead based on the position information of the nozzles in the uniform inkjet color section;

[0103] The specific steps are as follows:

[0104] S331: Obtain the minimum nozzle number N1 and the maximum nozzle number N2 of the uniform ink color part in the printhead according to the position information;

[0105] For example, if the nozzles numbered 1 to 5 in the diagram are the nozzles in the part of the printhead where the ink color is uniform, then N1 = 1 and N2 = 5.

[0106] S332: The length L2 of the uniform ink color part in the printhead is calculated according to the formula L2=(N2-N1)*d, where d is the distance between two adjacent nozzles.

[0107] S44: Compare the initial step distance D1 with the length L2 of the uniform inkjet color portion in the printhead;

[0108] S45: Determine the step distance after one scan and printing based on the comparison results.

[0109] In order to ensure that the part printed using printhead precision is completed entirely by the uniformly ink-jetting nozzles, this embodiment compares the initial step distance D1 with the length L2 of the uniformly ink-jetting part in the printhead, and then determines the final step distance used for printing based on the comparison result.

[0110] S45: Determining the step distance after one scan and printing by the printhead based on the comparison results specifically includes the following steps:

[0111] S451: If the initial step distance D1 is less than or equal to the length L2 of the uniform ink color portion in the printhead, then the initial step distance D1 is used as the step distance after one scan and printing of the printhead.

[0112] S452: If the initial step distance D1 is greater than the length L2 of the uniform ink color portion in the printhead, then the length L2 of the uniform ink color portion in the printhead is used as the step distance after one scan and print.

[0113] The printing equipment first processes the image to be printed to obtain the dot matrix data of the printed image, and then controls the printhead to spray ink at the corresponding positions on the printing medium according to the dot matrix data to form the printed image.

[0114] Since inkjet printing is performed by the printhead, the dot matrix data used to control the ink ejection of that printhead is the dot matrix data corresponding to that printhead. Once the dot matrix data of the printhead is determined, the amount of ink printed during printing is also determined. Therefore, the amount of ink printed by the printhead can be adjusted by adjusting the dot matrix data. The formula for calculating the ink volume difference in this step is Vd = M1 - M2, where M1 is the first ink volume and M2 is the second ink volume.

[0115] S5: Based on the stepping distance and the position information, control the nozzles of at least a portion of the inkjet color uniform part of the printhead to print according to the printhead precision, and the remaining nozzles to print according to the dot matrix position printed with printhead precision.

[0116] Once the nozzles for precise printing and uniform inkjet color are determined, the image to be printed can be processed to obtain the printing data corresponding to these nozzles. This data obtained through image processing is dot matrix data. Dot matrix data consists of multiple data points distributed in a matrix array. The position of these data points within the matrix array is the dot matrix position. For example, a matrix B with r rows and s columns can represent the dot matrix data of the first printhead, and a matrix C with r rows and s columns can represent the dot matrix data of the second printhead. Where data b... ij The dot position in the matrix array is at row i, column j, and the data is C. ij In the matrix array, the dot position is also in the i-th row and j-th column. In this case, the data b ij With data C ij At the same dot matrix position. The dot matrix data is divided into ink-ejecting data and non-ink-ejecting data. If the data is ink-ejecting data, the printhead is controlled to eject ink; if the data is non-ink-ejecting data, the printhead is controlled not to eject ink. The dot matrix position printed by the printhead refers to the dot matrix position of the ink-ejecting data in the printhead's dot matrix data. The other nozzles print according to the dot matrix position using printhead precision printing. This means that if the data at a certain dot matrix position of a nozzle with uniform ink color and printhead precision printing is non-ink-ejecting data, then the data at the same dot matrix position of the other nozzles will also be non-ink-ejecting data; conversely, if the data at a certain dot matrix position of a nozzle with uniform ink color and printhead precision printing is ink-ejecting data, then the data at the same dot matrix position of the other nozzles can be either ink-ejecting or non-ink-ejecting data. In other words, the dot matrix positions printed by the other nozzles can only be selected from the dot matrix positions of the nozzles with uniform ink color and printhead precision printing. Since the dot matrix position of the ink-ejecting data corresponds one-to-one with the position of the printhead ejecting ink on the printing medium, the other nozzles will only eject ink at the positions of the nozzles with uniform ink color and printhead precision printing.

[0117] This embodiment utilizes nozzles in the printhead with uniform ink color printing to print at printhead precision, while the remaining nozzles repeatedly print only at the same dot matrix positions. This ensures image detail and eliminates the uneven color printing caused by inconsistent nozzles within the printhead, while maintaining the same ink volume. Because printhead precision printing is used, situations where the paper feed distance is a small multiple of the orifice spacing are avoided, thus preventing printing progress misalignment caused by machine paper feed errors, printhead installation errors, or machine vibration errors. Furthermore, this invention utilizes a portion of the printhead nozzles to print at printhead precision, combined with the remaining nozzles repeatedly printing at the same positions to achieve the original ink volume for the original printing precision, significantly improving the uniformity of the printed image.

[0118] Example 2

[0119] like Figure 5As shown in the embodiment, this method specifically describes one approach where, when the initial step distance D1 is less than or equal to the length L2 of the uniformly colored portion of the printhead, S5: based on the step distance and the position information, at least a portion of the nozzles in the uniformly colored portion of the printhead are controlled to print according to printhead precision, while the remaining nozzles are printed according to the dot matrix positions printed using printhead precision. This method includes the following steps:

[0120] S51: Select at least a portion of the nozzles from the nozzles in the uniform inkjet color area as the first group of nozzles based on the step distance and the position information, and select the remaining nozzles of the printhead as the second group of nozzles.

[0121] Since the initial step distance D1 is less than or equal to the length L2 of the uniform ink color section in the printhead, the initial step distance D1 is used as the step distance after one scan of the printhead. Therefore, a continuous nozzle can be selected from the nozzles of the uniform ink color section to install the printhead precision for printing, while the remaining nozzles are used for repeated printing.

[0122] For example Figure 4 The nozzles numbered 1 to 5 are the nozzles for the uniform ink color section. The length of the uniform ink color section is L2 = 4d. If the initial feed distance D1 is 3d, then the nozzles numbered 1 to 4 can be selected as the first group of nozzles, and the nozzles numbered 5 to 10 can be selected as the second group of nozzles.

[0123] S52: Control the first group of nozzles to print according to the printhead precision;

[0124] This means controlling the selected inkjet nozzles with uniform inkjet color to print images according to printhead precision.

[0125] S53: Obtain the printing data of the first group of nozzles as the first printing data;

[0126] The image to be printed is processed according to the nozzle precision to obtain dot matrix data printed according to the nozzle precision. The printing data belonging to the first group of nozzles is obtained from the aforementioned dot matrix data, which is the first printing data.

[0127] S54: Control the second group of nozzles to repeat printing according to the first printing data.

[0128] This means controlling the remaining nozzles to repeatedly print the printing data of the first group of nozzles.

[0129] Example 3

[0130] like Figure 6 As shown, in this embodiment, the ink droplets ejected by the printing device include a first type of ink droplet, a second type of ink droplet, and a third type of ink droplet, wherein the volume of the first type of ink droplet is larger than the volume of the second type of ink droplet, and the volume of the second type of ink droplet is larger than the volume of the third type of ink droplet.

[0131] This embodiment specifically describes another method for controlling at least a portion of the nozzles in the uniformly colored ink-spraying section of the printhead to print according to printhead precision when the initial step distance D1 is less than or equal to the length L2 of the uniformly colored ink-spraying portion in the printhead, in step 5: according to the step distance and the position information, the nozzles in at least a portion of the uniformly colored ink-spraying portion of the printhead print at the printhead precision, while the remaining nozzles print according to the dot matrix position printed using printhead precision. This method includes the following steps:

[0132] S501: Select at least a portion of the nozzles from the nozzles in the uniform inkjet color area as a first group of nozzles based on the step distance and the position information, and select the remaining nozzles of the printhead as a second group of nozzles.

[0133] Since the initial step distance D1 is less than or equal to the length L2 of the uniform ink color portion in the printhead, the initial step distance D1 is used as the step distance after one scan of the printhead. Therefore, a continuous nozzle can be selected from the nozzles of the uniform ink color portion to print according to the printhead precision, while the remaining nozzles are used for repeated printing.

[0134] S502: Control the first group of nozzles to print according to the printhead precision;

[0135] This means controlling the selected inkjet nozzles with uniform inkjet color to print images according to printhead precision.

[0136] S503: Obtain the printing data of the first group of nozzles as the first printing data;

[0137] The image to be printed is processed according to the nozzle precision to obtain dot matrix data printed according to the nozzle precision. The printing data belonging to the first group of nozzles is obtained from the aforementioned dot matrix data, which is the first printing data.

[0138] S504: After adjusting the data in the first print data that uses the third type of ink droplet to no ink droplet data, the first intermediate print data is obtained;

[0139] The first set of nozzles ejects three different types of ink droplets—a first type, a second type, and a third type—during printing according to the printhead's precision. To improve printing efficiency while ensuring print uniformity, the second printhead ejects the relatively larger first and second ink droplets during printing, instead of the smaller third type.

[0140] like Figure 7 and Figure 8 As shown, Figure 7 and Figure 8Each circle with a cross-section represents an ink droplet ejected from the printhead. The largest circle represents the droplet formed by the first type of ink droplet, the smallest circle represents the droplet formed by the second type of ink droplet, and the second largest circle represents the droplet formed by the third type of ink droplet. The first intermediate dot matrix data obtained by the aforementioned data adjustment method can ensure that the second group of nozzles ejects the first type of ink droplet at the position where the first group of nozzles ejects the first type of ink droplet, ejects the second type of ink droplet at the position where the first group of nozzles ejects the second type of ink droplet, and does not eject ink at the position where the first group of nozzles ejects the third type of ink droplet, thereby making the printed image uniform.

[0141] S505: Obtain the ink volume printed by the second group of nozzles using the first intermediate printing data as the third printing ink volume;

[0142] This step first calculates the ink volume used when printing with only the larger first and second ink droplets as the third printing ink volume.

[0143] S506: Compare the difference between the third printing ink volume and the ink volume;

[0144] S507: Obtain second printing data based on the comparison result between the first intermediate printing data and the third printing ink volume and the ink volume difference;

[0145] If the ink level in the third print is less than the ink level difference, it indicates insufficient ink; conversely, if it is greater, it indicates sufficient ink. If the ink level is insufficient, convert some of the second type of ink droplets into the first type. For example... Figure 8 and Figure 9 As shown, Figure 9 The largest circle represents the ink droplet formed by the first type of ink droplet, and the second largest circle represents the ink droplet formed by the second type of ink droplet. By adjusting the data using the aforementioned steps, the second set of nozzles can spray the first type of ink droplet, which originally had a medium spray volume, at the same position as the second type of ink droplet. This increases the overall ink volume of the second set of nozzles, allowing the total ink volume printed by all printheads to reach the original printing accuracy.

[0146] If the ink level is insufficient, add a third type of ink droplet to obtain the second print data. If the ink level is sufficient, directly use the first intermediate print data as the second print data.

[0147] S508: Control the second group of nozzles to print according to the second printing data.

[0148] Once the second set of print data is determined, the second set of nozzles can be controlled to repeat printing according to the second set of print data.

[0149] like Figure 11As shown, in a preferred embodiment, the aforementioned inkjet color uniform portion is the initial uniform portion, that is, the portion where the printhead first enters the printing area and the sprayed color is consistent. The figure shows that when the initial step distance is less than the nozzle length of the initial uniform portion of the printhead color difference, repeated printing is performed according to the initial step distance. Each repeated printing uses the data from the first printing. In the figure, the step distance is 1 / 3 of the printhead height. The first printing is for printhead installation accuracy, and the second and third printings are repetitions of the first printing.

[0150] Example 4

[0151] like Figure 10 As shown, in this embodiment, the ink droplets ejected by the printing device include a first type of ink droplet, a second type of ink droplet, and a third type of ink droplet, wherein the volume of the first type of ink droplet is larger than the volume of the second type of ink droplet, and the volume of the second type of ink droplet is larger than the volume of the third type of ink droplet.

[0152] This embodiment specifically describes a method where, when the initial step distance D1 is greater than the length L2 of the uniformly colored portion of the printhead, step S5: based on the step distance and the position information, at least a portion of the nozzles in the uniformly colored portion of the printhead are controlled to print according to printhead precision, while the remaining nozzles are printed according to the dot matrix positions printed using printhead precision. This method includes the following steps:

[0153] S510: Select the nozzles in the area with uniform inkjet color as the third group of nozzles based on the position information, and select the remaining nozzles of the printhead as the remaining nozzles as the fourth group of nozzles.

[0154] Since the initial step distance D1 is greater than the length L2 of the uniform ink color portion in the printhead, the step distance after one scan of the printhead is taken as the length L2 of the uniform ink color portion in the printhead. Therefore, the printhead precision can be set for printing using the uniform ink color portion in the printhead, while the other nozzles are used for repeated printing.

[0155] S520: Controls the third group of nozzles to print according to the printhead precision;

[0156] This means controlling the uniformity of ink color in the printhead to print images according to the printhead's precision.

[0157] S530: Obtain the printing data of the third group of nozzles as the third printing data;

[0158] The image to be printed is processed according to the nozzle precision to obtain dot matrix data printed according to the nozzle precision. The printing data belonging to the third group of nozzles is obtained from the aforementioned dot matrix data as the third printing data.

[0159] S540: After adjusting the data in the third print data that uses the third type of ink droplet to data that does not produce ink, the second intermediate print data is obtained;

[0160] The third set of nozzles ejects three different types of ink droplets—the first, the second, and the third—according to printhead precision. To ensure print uniformity while improving printing efficiency, the second printhead ejects the relatively larger first and second ink droplets during printing, instead of the smaller third ink droplets.

[0161] S550: Obtain the ink volume printed by the second group of nozzles using the second intermediate printing data as the fourth printing ink volume;

[0162] This step first calculates the ink volume used when printing with only the larger first and second ink droplets as the fourth printing ink volume.

[0163] S560: Compare the fourth printing ink volume with the difference in ink volume.

[0164] S570: Obtain third printing data based on the comparison result between intermediate printing data and the difference between the fourth printing ink volume and the ink volume;

[0165] If the ink volume of the fourth print is smaller than the ink volume difference, it indicates insufficient ink volume; conversely, it indicates sufficient ink volume. If the ink volume is insufficient, some of the second type of ink droplets are converted into the first type of ink droplets. If the ink volume is still insufficient, some third type of ink droplets are added to obtain the second print data, ensuring that the total ink volume printed by all printheads reaches the original printing precision. If the ink volume is sufficient, the second intermediate print data is directly used as the second print data.

[0166] S580: Controls the fourth group of nozzles to print according to the third printing data.

[0167] Once the second set of print data is determined, the fourth set of nozzles can be controlled to repeat the printing process according to the second set of print data.

[0168] Example 5

[0169] Please see Figure 12 This embodiment provides a printing apparatus for eliminating image color difference, comprising:

[0170] The first printing ink volume acquisition module is used to acquire the amount of ink required to print the image to be printed using the original printing precision as the first printing ink volume.

[0171] The second printing ink volume acquisition module is used to acquire the amount of ink required for printing the image to be printed using the nozzle precision as the second printing ink volume.

[0172] A position information acquisition module, wherein the position information acquisition module is used to acquire the position information of the nozzles in the uniform ink color part of the printhead;

[0173] The step distance determination module, wherein the step distance acquisition module is used to determine the step distance after one scan and printing by the printhead based on the position information and the ink volume difference between the first printing ink volume and the second printing ink volume;

[0174] The control module is used to control at least a portion of the nozzles in the printhead with uniform ink color to print according to the printhead precision, based on the step distance and the position information, while the remaining nozzles print according to the dot matrix position printed with printhead precision.

[0175] The step distance determination module also includes:

[0176] The ink volume difference acquisition submodule is used to acquire the ink volume difference Vd between the second printing ink volume and the first printing ink volume.

[0177] The calculation submodule is used to calculate the initial step distance according to the formula D1=1 / (Vd / Vr+1)*L1, where L1 is the printhead length, D1 is the initial step distance, and Vr is the second printing ink volume;

[0178] The length acquisition submodule is used to determine the length L2 of the uniform ink color part in the printhead based on the position information of the nozzle in the uniform ink color part.

[0179] The comparison submodule is used to compare the initial step distance D1 with the length L2 of the uniform ink color portion in the printhead;

[0180] The step distance determination submodule is used to determine the step distance after one scan and printing by the printhead based on the comparison results.

[0181] Example 6

[0182] In addition, combined Figure 13 The image color difference elimination printing method described in this embodiment of the invention can be implemented by an image color difference elimination printing device. Figure 13 A schematic diagram of the hardware structure of a printing device for eliminating image color difference provided in an embodiment of the present invention is shown.

[0183] Printing equipment for eliminating color differences in images may include a processor 401 and a memory 402 storing computer program instructions.

[0184] Specifically, the processor 401 may include a central processing unit (CPU), an application specific integrated circuit (ASIC), or one or more integrated circuits that can be configured to implement the embodiments of the present invention.

[0185] Memory 402 may include mass storage for data or instructions. For example, and not limitingly, memory 402 may include a hard disk drive (HDD), a floppy disk drive, flash memory, optical disk, magneto-optical disk, magnetic tape, or a Universal Serial Bus (USB) drive, or a combination of two or more of these. Where appropriate, memory 402 may include removable or non-removable (or fixed) media. Where appropriate, memory 402 may be internal or external to a data processing device. In a particular embodiment, memory 402 is a non-volatile solid-state memory. In a particular embodiment, memory 402 includes read-only memory (ROM). Where appropriate, the ROM may be a mask-programmed ROM, a programmable ROM (PROM), an erasable PROM (EPROM), an electrically erasable PROM (EEPROM), an electrically rewritable ROM (EAROM), or flash memory, or a combination of two or more of these.

[0186] The processor 401 reads and executes computer program instructions stored in the memory 402 to implement any of the data addressing methods for random area printing in the above embodiments.

[0187] In one example, the printing device for eliminating image color difference may also include a communication interface 403 and a bus 410. For example, Figure 6 As shown, the processor 401, memory 402, and communication interface 403 are connected through bus 410 and complete communication with each other.

[0188] The communication interface 403 is mainly used to realize communication between various modules, devices, units and / or equipment in the embodiments of the present invention.

[0189] Bus 410 includes hardware, software, or both, that couples components used for fractional ink volume output together. For example, and not limitingly, the bus may include an Accelerated Graphics Port (AGP) or other graphics bus, an Enhanced Industry Standard Architecture (EISA) bus, a Front Side Bus (FSB), HyperTransport (HT) interconnect, an Industry Standard Architecture (ISA) bus, an Infinite Bandwidth Interconnect, a Low Pin Count (LPC) bus, a memory bus, a Microchannel Architecture (MCA) bus, a Peripheral Component Interconnect (PCI) bus, a PCI-Express (PCI-X) bus, a Serial Advanced Technology Attachment (SATA) bus, a Video Electronics Standards Association Local (VLB) bus, or other suitable buses, or combinations of two or more of these. Where appropriate, bus 410 may include one or more buses. While specific buses are described and illustrated in embodiments of the invention, the invention contemplates any suitable bus or interconnect.

[0190] Example 7

[0191] Furthermore, in conjunction with the printing method for eliminating image color difference in the above embodiments, this invention can be implemented using a computer-readable storage medium. This computer-readable storage medium stores computer program instructions; when executed by a processor, these computer program instructions implement any of the printing methods for eliminating image color difference in the above embodiments.

[0192] The above is a detailed description of the printing method, apparatus, device, and storage medium for eliminating image color difference provided in the embodiments of the present invention.

[0193] It should be clarified that the present invention is not limited to the specific configurations and processes described above and shown in the figures. For the sake of brevity, detailed descriptions of known methods are omitted here. In the above embodiments, several specific steps are described and shown as examples. However, the method process of the present invention is not limited to the specific steps described and shown. Those skilled in the art can make various changes, modifications, and additions, or change the order of steps, after understanding the spirit of the present invention.

[0194] The functional blocks shown in the above-described structural diagram can be implemented as hardware, software, firmware, or a combination thereof. When implemented in hardware, they can be, for example, electronic circuits, application-specific integrated circuits (ASICs), appropriate firmware, plug-ins, function cards, etc. When implemented in software, the elements of this invention are programs or code segments used to perform the required tasks. The programs or code segments can be stored on a machine-readable medium or transmitted over a transmission medium or communication link via data signals carried in a carrier wave. "Machine-readable medium" can include any medium capable of storing or transmitting information. Examples of machine-readable media include electronic circuits, semiconductor memory devices, ROM, flash memory, erasable ROM (EROM), floppy disks, CD-ROMs, optical disks, hard disks, fiber optic media, radio frequency (RF) links, etc. Code segments can be downloaded via computer networks such as the Internet, intranets, etc.

[0195] It should also be noted that the exemplary embodiments mentioned in this invention describe methods or systems based on a series of steps or apparatus. However, this invention is not limited to the order of the steps described above; that is, the steps can be performed in the order mentioned in the embodiments, or in a different order, or several steps can be performed simultaneously.

[0196] The above description is merely a specific embodiment of the present invention. Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, modules, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here. It should be understood that the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and these modifications or substitutions should all be covered within the protection scope of the present invention.

Claims

1. A printing method for eliminating color differences in images, characterized in that, The method includes: S1: Obtain the amount of ink required to print the image to be printed using the original printing precision as the first printing ink amount; S2: Obtain the amount of ink required to print the image to be printed using the printhead precision as the second printing ink amount; S3: Obtain the position information of the nozzles in the part of the printhead where the ink color is uniform; S4: Determine the step distance of the printhead after one scan and print based on the position information and the ink volume difference between the first and second printing ink volumes; S5: Based on the stepping distance and the position information, control at least a portion of the nozzles in the printhead with uniform ink color to print according to printhead precision, and the remaining nozzles to print according to the dot matrix positions printed with printhead precision. The dot matrix positions printed by the printhead refer to the dot matrix positions of the ink output data in the printhead's dot matrix data. Printing according to the dot matrix positions printed with printhead precision by the remaining nozzles means that if the ink color is uniform and the data at a certain dot matrix position of the nozzle printed with printhead precision is non-inking data, then the data at the same dot matrix position of the remaining nozzles will also be non-inking data; if the ink color is uniform and the data at a certain dot matrix position of the nozzle printed with printhead precision is ink output data, then the data at the same dot matrix position of the remaining nozzles will either be ink output data or non-inking data.

2. The printing method for eliminating image color difference according to claim 1, characterized in that, S3: Obtaining the position information of the nozzles in the uniform inkjet color portion of the printhead further includes the following steps; S31: Control the printhead to print the test pattern and then scan the printed test pattern; S32: Obtain the location of color difference in each printhead by scanning the test pattern obtained from the printout.

3. The printing method for eliminating image color difference according to claim 1, characterized in that, The nozzle precision is lower than the original printing precision of the image to be printed.

4. The printing method for eliminating image color difference according to any one of claims 1 to 3, wherein step S4: determining the step distance of the printhead after one scan and printing based on the position information and the ink volume difference between the first printing ink volume and the second printing ink volume, includes the following steps: S41: Obtain the ink volume difference Vd between the second printing ink volume and the first printing ink volume; S42: Obtain the initial step distance based on the printhead length, the second printing ink volume, and the ink volume difference; S43: Determine the length L2 of the uniform inkjet color section in the printhead based on the position information of the nozzles in the uniform inkjet color section; S44: Compare the initial step distance D1 with the length L2 of the uniform inkjet color portion in the printhead; S45: Determine the step distance after one scan and printing based on the comparison results.

5. The printing method for eliminating image color difference according to claim 4, characterized in that: In step S42: obtaining the initial step distance based on the printhead length, the second printing ink volume, and the ink volume difference, the initial step distance is calculated according to the formula D1=1 / (Vd / Vr+1)*L1, where L1 is the printhead length, D1 is the initial step distance, and Vr is the second printing ink volume.

6. The printing method for eliminating image color difference according to claim 4, characterized in that: S45: Determining the step distance after one scan and printing by the printhead based on the comparison results includes the following steps: S451: If the initial step distance D1 is less than or equal to the length L2 of the uniform ink color portion in the printhead, then the initial step distance D1 is used as the step distance after one scan and printing of the printhead. S452: If the initial step distance D1 is greater than the length L2 of the uniform ink color portion in the printhead, then the length L2 of the uniform ink color portion in the printhead is used as the step distance after one scan and print.

7. The printing method for eliminating image color difference according to claim 6, characterized in that, If the initial step distance D1 is less than or equal to the length L2 of the uniform ink color portion in the printhead, then step S5 includes the following steps: S51: Select at least a portion of the nozzles from the nozzles in the uniform inkjet color area as the first group of nozzles based on the step distance and the position information, and select the remaining nozzles of the printhead as the second group of nozzles. S52: Control the first group of nozzles to print according to the printhead precision; S53: Obtain the printing data of the first group of nozzles as the first printing data; S54: Control the second group of nozzles to repeat printing according to the first printing data.

8. The printing method for eliminating image color difference according to claim 6, characterized in that, The ink droplets ejected by the printing device include a first type of ink droplet, a second type of ink droplet, and a third type of ink droplet, wherein the volume of the first type of ink droplet is larger than the volume of the second type of ink droplet, and the volume of the second type of ink droplet is larger than the volume of the third type of ink droplet. If the initial step distance D1 is less than or equal to the length L2 of the uniformly colored portion of the inkjet in the printhead, step S5 includes the following steps: S501: Select at least a portion of the nozzles from the nozzles in the uniform inkjet color area as a first group of nozzles based on the step distance and the position information, and select the remaining nozzles of the printhead as a second group of nozzles. S502: Control the first group of nozzles to print according to the printhead precision; S503: Obtain the printing data of the first group of nozzles as the first printing data; S504: After adjusting the data in the first print data that uses the third type of ink droplet to no ink droplet data, the first intermediate print data is obtained; S505: Obtain the ink volume printed by the second group of nozzles using the first intermediate printing data as the third printing ink volume; S506: Compare the difference between the third printing ink volume and the ink volume; S507: Obtain second printing data based on the comparison result between the first intermediate printing data and the third printing ink volume and the ink volume difference; S508: Control the second group of nozzles to print according to the second printing data; If the initial step distance D1 is greater than the length L2 of the uniform ink color portion in the printhead, step S5 includes the following steps: S510: Select the nozzles in the area with uniform inkjet color as the third group of nozzles based on the position information, and select the remaining nozzles of the printhead as the remaining nozzles as the fourth group of nozzles. S520: Controls the third group of nozzles to print according to the printhead precision; S530: Obtain the printing data of the third group of nozzles as the third printing data; S540: After adjusting the data in the third print data that uses the third type of ink droplet to data that does not produce ink, the second intermediate print data is obtained; S550: Obtain the ink volume printed by the second group of nozzles using the second intermediate printing data as the fourth printing ink volume; S560: Compare the fourth printing ink volume with the difference in ink volume; S570: Obtain third printing data based on the comparison result between the second intermediate printing data and the fourth printing ink volume and the ink volume difference; S580: Controls the fourth group of nozzles to print according to the third printing data.

9. A printing apparatus for eliminating color differences in images, characterized in that, include: The first printing ink volume acquisition module is used to acquire the amount of ink required to print the image to be printed using the original printing precision as the first printing ink volume. The second printing ink volume acquisition module is used to acquire the amount of ink required for printing the image to be printed using the nozzle precision as the second printing ink volume. A position information acquisition module, wherein the position information acquisition module is used to acquire the position information of the nozzles in the uniform ink color part of the printhead; The step distance determination module, wherein the step distance acquisition module is used to determine the step distance after one scan and printing by the printhead based on the position information and the ink volume difference between the first printing ink volume and the second printing ink volume; The control module is used to control at least a portion of the nozzles in the printhead with uniform ink color to print according to printhead precision based on the stepping distance and the position information, while the remaining nozzles print according to the dot matrix positions printed with printhead precision. The dot matrix positions printed by the printhead refer to the dot matrix positions of the ink output data in the printhead's dot matrix data. Printing according to the dot matrix positions printed with printhead precision by the remaining nozzles means that if the ink color is uniform and the data at a certain dot matrix position of a nozzle printed with printhead precision is non-inking data, then the data at the same dot matrix position of the remaining nozzles will also be non-inking data; conversely, if the ink color is uniform and the data at a certain dot matrix position of a nozzle printed with printhead precision is ink output data, then the data at the same dot matrix position of the remaining nozzles will either be ink output data or non-inking data.

10. A printing device for eliminating color differences in images, characterized in that, include: At least one processor, at least one memory, and computer program instructions stored in the memory, which, when executed by the processor, implement the method as described in any one of claims 1-8.

Images