A test printing method before jet printing processing and an inkjet printing system

Abstract

The application relates to a test printing method before jet printing processing and an inkjet printing system. The test printing method comprises the following steps: dividing all nozzles of a nozzle module into multiple groups; making each group of nozzles print according to a test pattern, the test pattern comprising a test area and a code area, and multiple nozzles in the same group printing along a test straight line in the Y direction in the test area; multiple nozzles of each group of nozzles printing identification codes in the code area respectively; acquiring deviation amounts of droplets sprayed by each nozzle in the test area in the X direction and the Y direction; judging whether the ratio of the number of normal nozzles to the number of all nozzles is greater than or equal to a preset qualified ratio; if the ratio of the number of normal nozzles to the number of all nozzles is greater than or equal to the qualified ratio, shielding all abnormal nozzles except the normal nozzles, and completing the test printing. The application is convenient for determining the landing point deviation of the droplets sprayed by the nozzles, and abnormal nozzles can be quickly found out by using the identification codes.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of display screen processing, and particularly relates to a test printing method before inkjet printing processing and an inkjet printing system. BACKGROUND

[0002] Inkjet printing technology is increasingly applied in industrial production, and is applied in preparation of large-area pressure sensors, radio frequency identification tags RFID, flexible solar cells, and flexible OLEDs, etc. The basic structure of OLED is composed of an anode, a hole injection layer, a hole transport layer, an organic light-emitting layer, an electron transport layer, an electron injection layer, and a cathode.

[0003] With respect to the integrity of the nozzles, there is a need to collect functional information about the ink head, including detecting non-working or broken nozzles. Such information is important during the initial production phase of inkjet head calibration, and more importantly, during the development phase and recalibration phase of the key technology.

[0004] In the related art, test printing is needed before actual printing processing, so as to determine whether the ink head module meets the printing requirements according to the state of all nozzles of the ink head module. A plurality of nozzles of the ink head module prints a line segment in turn, and all line segments are arranged at intervals. By imaging all line segments, whether each line segment has a blank area is determined according to the actual imaging result of each line segment, so as to determine whether a nozzle is in an abnormal state.

[0005] However, in high-precision printing processing, it is necessary to ensure that the deviation between the landing position of the droplet sprayed by the nozzle and the planned landing position is at a small level. It is difficult to determine the landing deviation of the droplet sprayed by the actual nozzle by printing a line segment. In addition, when the printed line segment is matched with the corresponding nozzle, all line segments need to be imaged, and then the line segment and the nozzle are matched one by one according to the positions and printing sequences of the plurality of nozzles. Therefore, it is difficult to match the printed line segment with the nozzle, that is, it is difficult to find out the abnormal nozzle. SUMMARY

[0006] Embodiments of the present application provide a test printing method before inkjet printing processing and an inkjet printing system, to solve the technical problems that it is difficult to determine the landing deviation of the droplet sprayed by the nozzle and it is difficult to find out the abnormal nozzle according to the printing result in the related art.

[0007] In a first aspect, a test printing method before inkjet printing processing is provided, comprising:

[0008] numbering all nozzles of an ink head module used for printing;

[0009] dividing all nozzles of the ink head module into a plurality of groups, and the spacing of the plurality of nozzles of each group of nozzles in the X direction is consistent;

[0010] Each group of nozzles prints according to a test pattern, the test pattern including a test area and a code area, the nozzles in the same group printing along a test line in the Y direction in the test area, and each nozzle printing a drop corresponding to a drop landing point; the nozzles in each group printing an identification code in the code area, the drop landing point of each nozzle being spaced apart from the identification code printed by the nozzle in the X direction, and the identification code of each nozzle corresponding to the number of the nozzle;

[0011] Theoretical drop landing positions of all the nozzles are obtained, actual drop landing positions of all the nozzles in the test area are obtained, and the nozzles corresponding to the drop landing points are located by using the identification codes, so as to obtain deviation amounts of the drops printed by each nozzle in the test area in the X direction and the Y direction;

[0012] The number of normal nozzles whose deviation amounts in the X direction and the Y direction are within a preset standard deviation range is obtained.

[0013] It is determined whether the ratio of the number of normal nozzles to the number of all the nozzles is greater than or equal to a preset qualified ratio.

[0014] If the ratio of the number of normal nozzles to the number of all the nozzles is greater than or equal to the qualified ratio, all the abnormal nozzles except the normal nozzles are shielded, and the test printing is completed.

[0015] In some embodiments, if the ratio of the number of normal nozzles to the number of all the nozzles is less than the qualified ratio, all the abnormal nozzles are adjusted until the ratio of the number of normal nozzles to the number of all the nozzles is greater than or equal to the qualified ratio.

[0016] In some embodiments, the identification code includes a binary code, and the binary code is distributed in the X direction.

[0017] In some embodiments, the code area includes a plurality of rows of pixel areas, the rows of pixel areas are spaced apart in the Y direction, and a plurality of pixel areas in each row of pixel areas are uniformly spaced apart in the X direction, and each drop landing point of the drops printed by each nozzle in the code area corresponds to a row of pixel areas.

[0018] Each nozzle prints a specified pixel area in each row of pixel areas to obtain a binary code composed of blank pixel areas and filled pixel areas.

[0019] In some embodiments, the method of dividing all the nozzles of the printhead module into a plurality of groups, the nozzles in each group having a same spacing in the X direction, includes:

[0020] The projection positions of all the nozzles of the printhead module in the X direction are obtained to obtain an X direction projection position data set of the X direction projections of all the nozzles;

[0021] A standard spacing range of the X direction projections of adjacent nozzles in the same group is obtained.

[0022] In the X-direction projection position data set, a plurality of nozzles arranged at equal intervals are selected, and the interval between adjacent nozzles is within the standard interval range, to obtain a group of nozzles, and the remaining nozzles are divided into multiple groups according to this rule.

[0023] In some embodiments, the standard interval range of the projections of adjacent nozzles in the same group in the X-direction is obtained, comprising:

[0024] The radius of the liquid drop ejected by the nozzle and falling on the substrate is obtained.

[0025] The standard interval range is greater than 2 times the radius of the liquid drop.

[0026] In some embodiments, the preset process of the standard deviation range comprises:

[0027] According to the printing height of the nozzle module and the maximum ejection deflection angle of the nozzles of the nozzle module, the maximum deviation amount of the liquid drop ejected by the nozzle in the X-direction and the Y-direction is calculated to obtain the standard deviation range.

[0028] In some embodiments, the adjustment of all abnormal nozzles comprises:

[0029] The nozzle whose deviation amount in the Y-direction is not within the preset standard deviation range is selected and is adjusted in turn to reduce the ejection angle of the nozzle relative to the Y-direction.

[0030] In some embodiments, the adjustment of all abnormal nozzles further comprises:

[0031] The nozzle whose deviation amount in the X-direction is not within the preset standard deviation range is selected and the ejection waveform of the nozzle module is adjusted.

[0032] The technical scheme provided by the present application has the beneficial effects of:

[0033] The test printing method before printing provided by the embodiments of the present application is used to print a test straight line along the Y-direction in each test area for each group of nozzles, and the actual position of the liquid drop landing point and the theoretical position of the liquid drop landing point are compared to determine the deviation amount of the liquid drop ejected by each nozzle in the X-direction and the Y-direction, that is, the landing accuracy of the liquid drop ejected by the nozzle.

[0034] Meanwhile, each group of nozzles prints a corresponding identification code in the respective encoding area, and the landing position of the droplets sprayed by each nozzle in the test area is spaced apart from the identification code printed by the nozzle in the X direction, so that the landing position of the droplets sprayed by each nozzle in the test area can be marked by the identification code, and the nozzle corresponding to each droplet landing position in the test area can be determined according to the correspondence between the identification code and the nozzle code, so as to locate the nozzle and facilitate finding the abnormal nozzle with abnormal droplets.

[0035] In addition, if the number of abnormal nozzles is too large to meet the high-precision printing requirement, the abnormal nozzles can be located and picked out by the identification code and the nozzle code, so as to facilitate adjustment of the abnormal nozzles, so that the printhead module meets the high-precision printing processing requirement.

[0036] In a second aspect, a kind of inkjet printing system is provided, comprising:

[0037] A printhead module, the printhead module comprises a plurality of nozzles arranged in Y direction, and the printhead module is used for printing on substrate;

[0038] A conveying module, the conveying module is used for conveying substrate in X direction;

[0039] A control module, the control module controls the printhead module and the conveying module according to the test printing method before printing processing as described above.

[0040] Another embodiment of the present application provides a kind of inkjet printing system, since the inkjet printing system is printed according to the test printing method before printing processing as described above, so the beneficial effects of the inkjet printing system and the beneficial effects of the test printing method before printing processing described above are consistent, which will not be repeated here. BRIEF DESCRIPTION OF DRAWINGS

[0041] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0042] Figure 1 The flow chart of the test printing method before printing processing provided by the embodiments of the present application;

[0043] Figure 2 The schematic diagram of the printhead module provided by the embodiments of the present application;

[0044] Figure 3 The schematic diagram of the test pattern provided by the embodiments of the present application;

[0045] Figure 4 A schematic diagram of adjacent droplets provided for an embodiment of the present application;

[0046] Figure 5 A schematic diagram of the theoretical landing point and the actual landing point of a droplet in a test area provided for an embodiment of the present application;

[0047] Figure 6 A schematic diagram of the jet angle of a nozzle provided for an embodiment of the present application. DETAILED DESCRIPTION

[0048] To make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present application with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are some but not all of the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort belong to the scope of the present application.

[0049] The embodiments of the present application provide a test printing method before jet printing processing and an inkjet printing system. The test printing method before jet printing processing records that each group of nozzles prints a test straight line in the Y direction in a test area, and simultaneously prints an identification code in a coding area. The landing point of the droplet ejected by each nozzle in the test area is spaced in the X direction from the identification code. The landing point of the droplet can be corresponded to the nozzle one by one through the identification code and the coding of the nozzle. The abnormal droplet can be picked out through the deviation between the landing point and the actual landing point of the droplet in the test area. The abnormal nozzle can be found out through the identification code of the abnormal droplet. The technical problems that it is difficult to determine the deviation of the landing point of the droplet ejected by the nozzle and it is difficult to find out the abnormal nozzle according to the printing result in the related art are solved.

[0050] Reference Figures 1-3 A test printing method before jet printing processing, comprising the steps of

[0051] S100, numbering all nozzles of a print head module used for printing.

[0052] S200, dividing all nozzles of the print head module into multiple groups. The spacing of the multiple nozzles of each group of nozzles in the X direction is consistent.

[0053] S300, making each group of nozzles print according to a test pattern. The test pattern comprises a test area and a coding area. The multiple nozzles of the same group print a test straight line in the Y direction in the test area, and the droplet ejected by each nozzle corresponds to a droplet landing point. The multiple nozzles of each group of nozzles print an identification code in the coding area respectively. The landing point of the droplet ejected by each nozzle is spaced in the X direction from the identification code printed by the nozzle. The identification code of each nozzle corresponds to the coding of the nozzle.

[0054] S400, acquiring the theoretical drop landing position of the drops sprayed by all the nozzles, acquiring the actual drop landing position of the drops sprayed by all the nozzles in the test area, and locating the nozzle corresponding to the drop landing position by using the identification code, to obtain the deviation amount of the drops sprayed by each nozzle in the test area in the X direction and the Y direction.

[0055] S500, acquiring the number of normal nozzles whose deviation amount in the X direction and the Y direction is within the preset standard deviation range.

[0056] S600, judging whether the ratio of the number of normal nozzles to the number of all the nozzles is greater than or equal to a preset qualified ratio.

[0057] S700, if the ratio of the number of normal nozzles to the number of all the nozzles is greater than or equal to the qualified ratio, shielding all the abnormal nozzles except the normal nozzles, and completing the test printing.

[0058] S800, if the ratio of the number of normal nozzles to the number of all the nozzles is less than the qualified ratio, adjusting all the abnormal nozzles until the ratio of the number of normal nozzles to the number of all the nozzles is greater than or equal to the qualified ratio.

[0059] In this way, when printing, each group of nozzles respectively prints a test straight line along the Y direction in the respective test area, and the actual position of the drop landing point and the theoretical position of the drop landing point of the test straight line are compared to determine the deviation amount of the drops sprayed by each nozzle in the X direction and the Y direction, that is, the drop landing precision of the nozzles.

[0060] Referring to Figure 3 Meanwhile, each group of nozzles respectively prints the corresponding identification code in the respective coding area, the drop landing point of the drop sprayed by each nozzle in the test area is marked by the identification code, and the nozzle corresponding to each drop landing point in the test area is determined according to the corresponding relationship between the identification code and the coding of the nozzle, so as to locate the nozzle and facilitate finding the abnormal nozzle with abnormal drops.

[0061] In addition, if the number of abnormal nozzles is too large and does not meet the high-precision printing requirement, the abnormal nozzles are located and picked out by the identification code and the coding of the nozzle itself, and the abnormal nozzles are adjusted to make the printhead module meet the high-precision printing processing requirement.

[0062] In the step S100, all the nozzles of the printhead module used for printing are numbered. Specifically,

[0063] All the nozzles in the nozzle module correspond to a number, which can be one or a combination of Arabic numerals, Roman letters, and English letters. In this embodiment, all the nozzles in the nozzle module correspond to an Arabic numeral, and preferably, the Arabic numerals are arranged continuously, i.e., the numbers of all the nozzles are 1, 2, 3...n respectively.

[0064] In this way, the corresponding nozzle can be determined by the number.

[0065] In the step S200, all the nozzles in the nozzle module are divided into groups, and the spacing of the multiple nozzles in each group in the X direction is uniform. Specifically, the step S200 includes steps S210-S230.

[0066] In the step S210, the projection positions of all the nozzles in the X direction are obtained, and an X direction projection position data set of all the nozzles in the X direction is obtained.

[0067] In the step S220, the standard spacing range of the projections of adjacent nozzles in the X direction is obtained.

[0068] In the step S230, multiple nozzles arranged at equal spacing are selected from the X direction projection position data set, and the spacing of adjacent nozzles is within the standard spacing range, so as to obtain a group of nozzles, and the remaining nozzles are divided into multiple groups according to the rule.

[0069] In this way, by grouping the nozzles, the situation that the adjacent nozzles are too close and the droplets sprayed by the nozzles contact each other is avoided, and it is ensured that the droplets sprayed by the multiple nozzles in each group are independent, and the landing point of the droplets sprayed by each nozzle is convenient to determine.

[0070] In the step S210, the projection positions of all the nozzles in the X direction are obtained, and an X direction projection position data set of all the nozzles in the X direction is obtained. Specifically,

[0071] Referring to Figure 2 In this embodiment, the nozzles of the nozzle module include multiple rows, the multiple nozzles in each row are arranged at intervals, and the nozzles in the rows are staggered to increase the printing density and meet the high-resolution printing requirement. During printing, the nozzle module and the substrate move relative to each other in the X direction to print the substrate by the nozzle module. In order to increase the printing density, the arrangement length direction of each row of nozzles can be arranged at an angle with the Y direction.

[0072] All projections of all nozzles of the nozzle module in the X direction are arranged in a straight line in the Y direction with consistent spacing, where the spacing refers to the distance between the centers of adjacent projections. Let the spacing of the projections of the nozzles in the X direction be l, and taking the position of the projection of the most edge nozzle in the X direction as a reference, the coordinates of the projections of all nozzles in the X direction are obtained in turn as (0, 0), (0, l), (0, 2l), (0, 3l),..., (0, nl). The X direction projection position data set of the projections of all nozzles in the X direction is obtained in turn.

[0073] In step S220, a standard spacing range of the projections of adjacent nozzles in the X direction in the same group of nozzles is obtained. Specifically, the standard spacing range is obtained as follows.

[0074] The radius of a droplet falling on the substrate after being sprayed by the nozzle is obtained.

[0075] The standard spacing range is greater than 2 times the radius of the droplet.

[0076] Referring to Figure 4 In step S210, the nozzle module is caused to perform printing on the substrate, and the printing parameters and the cleanliness of the substrate are consistent with those in the test printing. The radius of the droplet is obtained by imaging the droplet with a high magnification camera, so as to obtain the radius of the droplet falling on the substrate after being sprayed by the nozzle.

[0077] Preferably, multiple droplets can be printed simultaneously, and the maximum value of the radius of the droplet is selected as the radius of the droplet falling on the substrate after being sprayed by the nozzle. In this way, the situation that the droplets sprayed by adjacent nozzles contact and merge can be further avoided, and the droplets in the test area are ensured to be in an independent state.

[0078] Therefore, the standard spacing is the spacing in the Y direction between the centers of two droplets sprayed by adjacent nozzles of each group of nozzles. The standard spacing range L is L > 2R, where R is the radius of the droplet.

[0079] In step S230, a plurality of nozzles arranged at equal spacing are selected from the X direction projection position data set, and the spacing between adjacent nozzles is within the standard spacing range, to obtain a group of nozzles, and the remaining nozzles are divided into multiple groups according to the rule. Specifically,

[0080] According to the interval l of the projection of all the nozzles in the X direction and the interval of the projection of each group of nozzles in the X direction needs to be within the standard interval range L, according to N>L / l, wherein N is the number of intervals between the projections of the multiple nozzles of each group of nozzles in the X direction in the projection of all the nozzles in the X direction. It can be understood that when L is 2 and l is 1, N needs to be greater than 2, that is, N can be selected to be a positive integer greater than 2, for example, N is 3, in the X direction projection position data set of the projection of all the nozzles in the X direction, the nozzles corresponding to the projections with coordinates (0, 0), (0, 4l), (0, 8l), (0, 12l)...(0, 4(n-1)l) are selected as a group of nozzles.

[0081] And according to this rule, the remaining nozzles are grouped. After all the nozzles of the nozzle module are grouped, the number of groups can be obtained.

[0082] In this way, it is ensured that when each group of nozzles prints in the test area, the droplets sprayed by adjacent nozzles will not touch or even merge, ensuring the independence of the droplets and facilitating subsequent analysis of the droplet landing position to determine abnormal nozzles.

[0083] Referring to Figure 3 , in the step S300, each group of nozzles prints according to the test pattern, the test pattern includes a test area and a code area, the multiple nozzles of the same group print along the test straight line in the Y direction in the test area, and the droplet landing position corresponding to each nozzle is printed by each nozzle; the multiple nozzles of each group of nozzles print identification codes in the code area, the landing position of the droplet sprayed by each nozzle is spaced apart from the identification code printed by the nozzle in the X direction, and the identification code of each nozzle corresponds to the number of the nozzle. Specifically,

[0084] The substrate is distributed with multiple test pattern printing areas according to the group number of the grouping of the nozzles, and each group of nozzles prints in the corresponding test pattern printing area. The test pattern is divided into a test area and a code area, and the test area and the code area are spaced apart in the X direction.

[0085] Referring to Figure 3 , the multiple nozzles of the same group print along the test straight line in the Y direction in the test area, and it can be understood that the landing positions of the multiple droplets sprayed by the multiple nozzles form a test straight line in the test area. During printing, according to the specific position of the nozzle, the jet waveform of the nozzle module can be adjusted, so that each group of nozzles can print a test straight line.

[0086] Referring to Figure 3 , as the nozzle moves in the X direction relative to the substrate, the nozzle further prints an identification code in the code area, each nozzle corresponds to an identification code, and the identification code of each nozzle is spaced apart from the landing position of the droplet printed by the nozzle in the test area in the X direction. In addition, the identification code printed by the nozzle corresponds to the code of the nozzle.

[0087] In this way, each group of nozzles prints the corresponding identification code in the respective encoding area, and the drop landing position of each nozzle in the test area is spaced apart from the identification code printed by the nozzle in the X direction, so that the drop landing position of each nozzle in the test area can be marked by the identification code, and the nozzle corresponding to each drop landing position in the test area can be determined according to the correspondence between the identification code and the nozzle code, so as to locate the nozzle and find the abnormal nozzle with abnormal drops.

[0088] In addition, since the drops printed by the nozzle in the test area are spaced apart from the identification code printed by the nozzle in the X direction, the identification code can be continuously printed in the encoding area after the nozzle prints in the test area, and the printing rhythm is more reasonable.

[0089] Referring to Figure 3 Further, in the embodiment, the identification code includes a binary code, and the binary code is distributed in the X direction.

[0090] The encoding area includes a plurality of rows of pixel areas, the plurality of rows of pixel areas are spaced apart in the Y direction, and the plurality of pixel areas in each row of pixel areas are uniformly spaced apart in the X direction, and each drop landing position of each nozzle in the encoding area corresponds to a row of pixel areas.

[0091] The specified pixel area in each row of pixel areas is printed by the nozzle to obtain a binary code composed of blank pixel areas and filled pixel areas.

[0092] In this way, the number of the nozzle can be processed in binary and used as the binary code required to be printed by the nozzle, so as to correspond the nozzle to the identification code. In addition, the nozzle corresponding to the drop landing position in the test area can be quickly located by interpreting the binary code corresponding to the drop landing position, so as to quickly locate the abnormal nozzle.

[0093] Referring to Figure 5 In step S400, the theoretical drop landing position of all nozzles is obtained, the actual drop landing position of all nozzles in the test area is obtained, and the nozzle corresponding to the drop landing position is located by using the identification code to obtain the deviation amount of the drop landing position of each nozzle in the test area in the X direction and the Y direction. Specifically,

[0094] The theoretical drop landing position of all nozzles of the nozzle module can be obtained by determining the theoretical drop landing position of each group of nozzles. When each group of nozzles prints the test straight line in the Y direction, the theoretical drop landing position of all nozzles of the group is the projection position of the group in the X direction.

[0095] Due to the influence of the spray angle of the nozzle, the degree of nozzle clogging, and the like, the actual landing position of the liquid droplets sprayed by the nozzle has a deviation from the theoretical landing position. After printing a straight line by the nozzles in the same group, imaging detection is performed to obtain the relative positions of all the liquid droplet landing positions when the nozzles in the same group print a straight line.

[0096] A corresponding relationship is established between the actual landing position of the liquid droplets sprayed by a nozzle and the theoretical landing position of the liquid droplets sprayed by the nozzle. In this embodiment, a nozzle at the uppermost edge in the Y direction is selected. The coordinate of the theoretical landing position of the liquid droplets sprayed by the nozzle is (X0, Y0), the coordinate of the actual landing position of the liquid droplets sprayed by the nozzle is (X1, Y1), and the absolute value ΔX of the corresponding difference in the X direction is obtained by X1-X0, and the absolute value ΔY of the corresponding difference in the Y direction is obtained by Y1-Y0.

[0097] Based on the absolute value ΔX of the corresponding difference in the X direction and the absolute value ΔY of the corresponding difference in the Y direction, the deviation amount in the X direction and the deviation amount in the Y direction between the actual landing position of the liquid droplets sprayed by the remaining nozzles and the theoretical landing position of the liquid droplets sprayed by the nozzles are calculated.

[0098] Specifically, the coordinates of the theoretical landing positions of the liquid droplets sprayed by the remaining nozzles are (a 01 , b 01 ), (a 02 , b 02 )...(a 0n , b 0n ), respectively, and the coordinates of the actual landing positions of the liquid droplets sprayed by the remaining nozzles are (a 11 , b 11 ), (a 12 , b 12 )...(a 1n , b 1n ), respectively.

[0099] The deviation amount in the X direction between the actual landing position of the liquid droplets sprayed by the remaining nozzles and the theoretical landing position of the liquid droplets sprayed by the nozzles can be calculated in sequence by using Formula 1.

[0100] Formula 1: D xn = | |a 1n -a 0n | - ΔX|

[0101] The deviation amount D x1 , D x2 , D x3 ...D xn in the X direction between the actual landing position of the liquid droplets sprayed by the remaining nozzles and the theoretical landing position of the liquid droplets sprayed by the nozzles can be obtained.

[0102] The deviation amount of the actual drop landing position of the remaining nozzles from the theoretical drop landing position of the nozzles in the Y direction can be calculated in sequence by using formula 2.

[0103] Formula 2: D Yn = | | b 1n -b 0n | - ΔY |.

[0104] The deviation amount of the actual drop landing position of the remaining nozzles from the theoretical drop landing position of the nozzles in the Y direction can be calculated in sequence by using formula 2. Y1 , D Y2 , D Y3 ... D Yn .

[0105] After obtaining the deviation amount of the drop landing position of the nozzles in a group in the X direction and the Y direction by the above steps, the deviation amount of the drop landing position of the nozzles in other groups in the X direction and the Y direction can be obtained in the same way, and the deviation amount of the drop landing position of all the nozzles in the X direction and the Y direction can be obtained.

[0106] It should be noted that due to the existence of the identification code, the actual drop landing position of the nozzle can be marked after the nozzle is actually printed, and the actual drop landing position of the nozzle can be corresponded to the theoretical drop landing position of the nozzle for subsequent calculation of the deviation amount of the drop landing position of each nozzle in the X direction and the Y direction.

[0107] In step S500, the number of normal nozzles whose deviation amounts in the X direction and the Y direction are within the preset standard deviation range is obtained. Specifically,

[0108] The preset process of the standard deviation range includes:

[0109] Referring to Figure 6 , according to the printing height of the nozzle module and the maximum jetting deflection angle of the nozzles of the nozzle module, the maximum deviation amount of the drop landing position of the nozzles in the X direction and the Y direction is calculated to obtain the standard deviation range.

[0110] Wherein, the printing height of the nozzle is H, and the jetting angle is θ. According to formula 3, the maximum deviation amount C X , C Y of the drop landing position of the nozzles in the X direction and the Y direction can be obtained.

[0111] Formula 3: C X = C Y = H * tan θ

[0112] Therefore, the standard deviation range in the X direction is ± C X , and the standard deviation range in the Y direction is ± C Y .

[0113] The deviation amount of the landing point of the liquid drop sprayed by each nozzle in the X direction is judged one by one whether it is within the standard deviation range in the X direction, and the deviation amount of the landing point of the liquid drop sprayed by each nozzle in the Y direction is judged one by one whether it is within the standard deviation range in the Y direction. The number of nozzles whose deviation amount of the landing point of the liquid drop sprayed in the X direction is within the standard deviation range in the X direction and whose deviation amount in the Y direction is within the standard deviation range in the Y direction is picked out to obtain the number of normal nozzles.

[0114] In step S600, it is judged whether the ratio of the number of normal nozzles to the number of all nozzles is greater than or equal to a preset qualified ratio. Specifically,

[0115] The qualified ratio includes one value in 80%-99%, and in this embodiment, the qualified ratio includes 80%, 81%, 82%, 83%,..., 97%, 98% or 99%.

[0116] In step S700, if the ratio of the number of normal nozzles to the number of all nozzles is greater than or equal to the qualified ratio, all abnormal nozzles except the normal nozzles are shielded, and the test printing is completed. Specifically,

[0117] When the ratio of the number of normal nozzles to the number of all nozzles is greater than or equal to the qualified ratio, step S700 is entered, at this time, all abnormal nozzles except the normal nozzles are shielded, and the test printing is completed. It can be understood that at this time, the number of abnormal nozzle holes is within a reasonable range, and the influence on printing is small.

[0118] In step S800, if the ratio of the number of normal nozzles to the number of all nozzles is less than the qualified ratio, all abnormal nozzles are adjusted until the ratio of the number of normal nozzles to the number of all nozzles is greater than or equal to the qualified ratio.

[0119] When the ratio of the number of normal nozzles to the number of all nozzles is less than the qualified ratio, step S800 is entered. At this time, all abnormal nozzles are adjusted until the ratio of the number of normal nozzles to the number of all nozzles is greater than or equal to the qualified ratio.

[0120] The adjustment of all abnormal nozzles includes:

[0121] The nozzles whose deviation amount in the Y direction is not within the preset standard deviation range are picked out and are adjusted in turn to reduce the jet angle of the nozzles relative to the Y direction.

[0122] In this way, by reducing the jet angle of the nozzles relative to the Y direction, the deviation amount of the liquid drop sprayed by the nozzles in the Y direction can be reduced, so that the number of nozzles whose deviation amount of the liquid drop sprayed in the Y direction exceeds the standard deviation range is reduced, and the number of abnormal nozzles is reduced.

[0123] Further, the adjustment of all abnormal nozzles further comprises:

[0124] The nozzles whose deviation in the X direction is not within the preset standard deviation range are picked out, and the jet waveform of the nozzle module is adjusted.

[0125] This step is independently performed from the step of reducing the jet angle of the nozzles in the Y direction, or can be performed after the step of reducing the jet angle of the nozzles in the Y direction. By adjusting the jet waveform of the nozzle module, the landing position of the droplets sprayed by the nozzles in the X direction is changed, so that the deviation of the droplets sprayed by the nozzles in the X direction is within the standard deviation range.

[0126] The embodiment of the present application provides a test printing method before inkjet printing processing. When printing, each group of nozzles respectively prints a test straight line along the Y direction in a respective test area, and the actual position of the droplet landing point and the theoretical position of the droplet landing point constituting the test straight line are compared to determine the deviation of the droplets sprayed by each nozzle in the X direction and the Y direction, that is, the landing precision of the droplets sprayed by the nozzles.

[0127] Meanwhile, each group of nozzles respectively prints a corresponding identification code in a respective coding area. The landing position of the droplets sprayed by each nozzle in the test area and the identification code printed by the nozzle in the coding area are spaced apart in the X direction, so that the landing position of the droplets sprayed by each nozzle in the test area can be marked by the identification code. According to the corresponding relationship between the identification code and the coding of the nozzle, the nozzle corresponding to each droplet landing point in the test area can be determined, so as to position the nozzle and facilitate the identification of abnormal nozzles with abnormal droplets.

[0128] In addition, if the number of abnormal nozzles is too large and does not meet the high-precision printing requirement, the abnormal nozzles are positioned and picked out through the identification code and the coding of the nozzle itself, so as to facilitate the adjustment of the abnormal nozzles, so that the nozzle module meets the high-precision printing processing requirement.

[0129] Another embodiment of the present application provides an inkjet printing system, comprising:

[0130] a nozzle module comprising a plurality of nozzles arranged in the Y direction, the nozzle module being used for printing on a substrate;

[0131] a conveying module used for conveying the substrate in the X direction;

[0132] a control module used for controlling the nozzle module and the conveying module according to the test printing method before inkjet printing processing.

[0133] In addition, it can be understood that the inkjet printing system further comprises a machine table, a visual detection camera, a nozzle moving mechanism, a power supply and other devices for ensuring normal operation of the inkjet printing system.

[0134] Another embodiment of the present application provides an inkjet printing system. Since the inkjet printing system is printed according to the test printing method before printing as described above, the beneficial effects of the inkjet printing system are consistent with those of the test printing method before printing, which will not be repeated here.

[0135] In the description of the present application, it should be understood that the positive direction of "X" in the drawings represents the right direction, and correspondingly, the negative direction of "X" represents the left direction; the positive direction of "Y" represents the front direction, and correspondingly, the negative direction of "Y" represents the rear direction; the directions or positional relationships indicated by the terms "X", "Y" and the like are based on the directions or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0136] In the description of the present application, it should be noted that the directions or positional relationships indicated by the terms "up", "down" and the like are based on the directions or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. Unless otherwise specified and limited, the terms "mounting", "connecting", "connecting" should be understood in a broad sense, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium, or it can be the communication between two elements inside. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0137] It should be noted that, in the present application, the relational terms such as "first" and "second", and the like, are used solely to distinguish one entity or action from another, without necessarily requiring or implying any actual relationship or order between such entities or actions. Moreover, the terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can also include other elements not expressly listed or inherent to such process, method, article, or apparatus. An element proceeded by "comprises... a" does not, without more constraints, exclude the existence of additional identical elements in the process, method, article, or apparatus that comprises the element.

[0138] The foregoing is merely illustrative of the principles of the application and various modifications can be made by those skilled in the art without departing from the spirit and scope of the application. The above embodiments are illustrative, and not restrictive, of the scope of the application.

Claims

1. A test printing method before inkjet printing processing, characterized in that, It includes: Number all the nozzles in the printhead module used for printing; The nozzles of the nozzle module are divided into multiple groups, and the spacing between the multiple nozzles in each group is consistent when projected in the X direction. Each group of nozzles is printed according to a test pattern, which includes a test area and a coding area. Multiple nozzles in the same group are printed along the test line in the Y direction in the test area, and the droplets ejected by each nozzle correspond to a droplet landing point. Multiple nozzles in each group are printed with identification codes in the coding area. The landing point of the droplets ejected by each nozzle and the identification code printed by that nozzle are spaced apart in the X direction. The identification code of each nozzle corresponds to the number of that nozzle. The coding area includes multiple rows of pixel areas, which are spaced apart in the Y direction. The multiple pixel areas in each row of pixel areas are evenly spaced in the X direction. The landing point of the droplets ejected by each nozzle in the coding area has a row of pixel areas corresponding to it. Obtain the theoretical landing position of all droplets ejected by the nozzles, obtain the actual landing position of all droplets ejected by the nozzles in the test area, and use the identification code to locate the nozzle corresponding to the droplet landing point, and obtain the deviation of each nozzle ejected by the droplet in the test area in the X and Y directions. Obtain the number of normal nozzles whose deviations in both the X and Y directions are within the preset standard deviation range; Determine whether the ratio of the number of normal nozzles to the total number of nozzles is greater than or equal to the preset qualified ratio; If the ratio of the number of normal nozzles to the total number of nozzles is greater than or equal to the qualified ratio, then all abnormal nozzles except the normal nozzles are blocked, and the test print is completed.

2. The test printing method before inkjet printing processing according to claim 1, characterized in that, If the ratio of the number of normal nozzles to the total number of nozzles is less than the acceptable ratio, all abnormal nozzles will be adjusted until the ratio of the number of normal nozzles to the total number of nozzles is greater than or equal to the acceptable ratio.

3. The test printing method before inkjet printing processing according to claim 1 or 2, characterized in that, The identification code includes binary encoding, which is distributed in the X direction.

4. The test printing method before inkjet printing processing according to claim 3, characterized in that, The nozzle prints a specified pixel area within each row of pixel areas to obtain a binary code consisting of blank pixel areas and filled pixel areas.

5. The test printing method before inkjet printing processing according to claim 1, characterized in that, The step of dividing all the nozzles of the nozzle module into multiple groups, with the spacing between the multiple nozzles in each group projected in the X direction being consistent, includes: Obtain the projected positions of all nozzles in the X-direction of the nozzle module, and obtain the dataset of X-direction projection positions of all nozzles in the X-direction. Obtain the standard spacing range of the projections of adjacent nozzles in the same group in the X direction; Select multiple nozzles arranged at equal intervals in the X-axis projection position dataset, ensuring that the spacing between adjacent nozzles is within the standard spacing range, to obtain a group of nozzles. Then, divide the remaining nozzles into multiple groups according to this rule.

6. The test printing method before inkjet printing processing according to claim 5, characterized in that, The process of obtaining the standard spacing range of the projections of adjacent nozzles in the same group along the X-axis includes: Obtain the radius of the droplets ejected from the nozzle that fall onto the substrate; Let the standard spacing range be greater than twice the droplet radius.

7. The test printing method before inkjet printing processing according to claim 1, characterized in that, The process of presetting the standard deviation range includes: Based on the printing height of the printhead module and the maximum spray angle of the nozzle of the printhead module, the maximum deviation of the droplets sprayed by the nozzle in the X and Y directions is calculated to obtain the standard deviation range.

8. The test printing method before inkjet printing processing according to claim 2, characterized in that, The adjustment of all abnormal nozzles includes: Select nozzles whose deviation in the Y direction is not within the preset standard deviation range, and rotate and adjust them in sequence to reduce the nozzle's spray angle relative to the Y direction.

9. The test printing method before inkjet printing processing according to claim 8, characterized in that, The adjustment of all abnormal nozzles also includes: Select nozzles whose deviation in the X direction is not within the preset standard deviation range, and adjust the spray waveform of the nozzle module.

10. An inkjet printing system, characterized in that, include: A printhead module comprising a plurality of nozzles arranged in the Y direction, the printhead module being used for printing on a substrate; A conveying module for conveying a substrate in the X direction; A control module that controls the printhead module and the conveying module according to the test printing method before inkjet printing as described in any one of claims 1 to 9.

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