Method for correcting light and dark lines between LED display modules and LED display screen

Abstract

The application belongs to the technical field of LED display screens, and provides an LED display module inter bright-dark line correction method and an LED display screen. The LED display module inter bright-dark line correction method comprises the following steps: preparing a first LED display module, determining a first distance L1 between a first side of the first LED display module and the center of an adjacent first LED lamp bead and a second distance L2 between the centers of two adjacent rows of first LED lamp beads, and determining a first width value W1 of a first joint gap formed when two first LED display modules are spliced in a first direction; a second LED display module is prepared by the same process, the position of a second solder pad on the second LED display module is corrected according to the above parameters, and the finally prepared second LED display module is not prone to bright-dark lines at the joint gap.

Description

Technical Field

[0001] This application relates to the field of LED display technology, and specifically to a method for correcting bright and dark lines between LED display modules and an LED display screen. Background Technology

[0002] In existing technologies, LED displays typically consist of multiple LED display modules spliced ​​together. Each LED display module usually includes a printed circuit board (PCB) and multiple LED chips mounted on the PCB. During the soldering process, such as reflow soldering, the LED display module undergoes significant temperature variations, causing its final dimensions to deviate from the design dimensions. This dimensional deviation can lead to situations where, after two LED display modules are spliced ​​together, the distance between the LED chips on either side of the seam is less than or greater than the distance between adjacent LED chips on a single LED display module. This results in bright or dark lines appearing at the seam between the two LED display modules. When the LED display plays videos or images, these bright or dark lines cause the displayed image to appear as a bright or dark grid, severely impacting the display's performance. Summary of the Invention

[0003] The purpose of this application is to provide a method for correcting bright and dark lines between LED display modules and an LED display screen, so as to solve the technical problem that dark or bright lines are easily generated at the seam between two LED display modules in the prior art.

[0004] To achieve the above objectives, the technical solution adopted in this application is as follows:

[0005] In a first aspect, a method for correcting bright and dark lines between LED display modules is provided, the method comprising:

[0006] A first printed circuit board is fabricated using a predetermined fabrication process. The first printed circuit board includes a first substrate and a plurality of first pads arranged in rows and columns on the first substrate. The first substrate has two first sides that are disposed opposite each other in a first direction. The plurality of first pads are centered between the two first sides and are arranged at equal intervals along the first direction.

[0007] Multiple first LED beads are soldered onto multiple first pads using a predetermined soldering process to obtain a first LED display module;

[0008] Determine the parameters, including the first distance L1 between the first side of the first LED display module and the center of the adjacent first LED bead, and the second distance L2 between the centers of two adjacent columns of first LED beads; and determine the first width value W1 of the first seam formed when the two first LED display modules are spliced ​​together along the first direction.

[0009] like >First predetermined ratio or If the second predetermined ratio is specified, then the predetermined manufacturing process is used to fabricate a second printed circuit board. The second printed circuit board includes a second substrate and a plurality of second pads arranged in rows and columns on the second substrate. The second substrate has two second sides disposed opposite to each other in the first direction. The plurality of rows of second pads are centered between the two second sides and are arranged sequentially at intervals along the first direction. In at least two rows of second pads near the same second side, the third distance L3 between the center of the second pad closest to the second side and the second side is between the first distance L1 and L2. Between; the fourth distance L4 between any two adjacent second pads in any other column is between the second distance L2 and 2L1+W1;

[0010] Multiple second LED beads are soldered onto multiple first pads using the predetermined welding process to obtain the finished second LED display module.

[0011] In some embodiments, for N+1 columns of the second pads adjacent to the same second side, the third distance L3 is equal to The fourth distance L4 is equal to

[0012] In some embodiments, The absolute value is less than 5% of the second distance L2.

[0013] In some embodiments, the first predetermined ratio is 102% to 108%; and / or, the second predetermined ratio is 92% to 98%.

[0014] In some embodiments, the second substrate and the first substrate are made of the same material and have the same structure; the second pad and the first pad are made of the same material and have the same structure; and the second LED bead and the first LED bead are of the same type.

[0015] In some embodiments, the step of “determining the first width value W1 of the first seam formed by splicing the two first LED display modules together along the first direction” includes: using a predetermined installation process to splice the two first LED display modules together along the first direction, and measuring the first width value W1 of the first seam formed between the two first LED display modules.

[0016] The step of “welding multiple second LED beads onto multiple first pads using the predetermined welding process to obtain a finished LED display module” further includes: splicing two second LED display modules together along a first direction using the predetermined installation process.

[0017] In some embodiments, the first substrate further has two third sides disposed opposite to each other in a second direction, and multiple rows of first pads are centered between the two third sides and are arranged at equal intervals along the second direction, wherein the second direction is perpendicular to the first direction;

[0018] The "determine parameters" step further includes: determining the fifth distance L5 between the third side of the first LED display module and the center of the adjacent first LED lamp bead, and the sixth distance L6 between the centers of two adjacent rows of first LED lamp beads; and determining the second width value W2 of the second seam where the two first LED display modules are spliced ​​together along the second direction;

[0019] In the step of "preparing a second printed circuit board using the predetermined preparation process", the second substrate has two fourth sides that are disposed opposite to each other in the second direction, and multiple rows of second pads are centered between the two fourth sides and are arranged at intervals along the second direction.

[0020] The step of "fabricating the second printed circuit board using the predetermined fabrication process" further includes: if >Third predetermined ratio or If the fourth predetermined ratio is less than a certain value, then the seventh distance L7 between the center of the second pad closest to the fourth side and the fourth side is between the fifth distance L5 and the fourth side. Between; the eighth distance L8 between any two adjacent rows of the second pads is between the sixth distance L6 and 2L5+W2.

[0021] In some embodiments, for the second pad in row M+1 near the same third side, the seventh distance L7 is equal to The eighth distance L8 is equal to

[0022] In some embodiments, The absolute value is less than 5% of the sixth distance L6.

[0023] In some embodiments, the third predetermined ratio is 102% to 108%; and / or, the fourth predetermined ratio is 92% to 98%.

[0024] In a second aspect, an LED display screen is provided, the LED display screen comprising at least two second LED display modules spliced ​​together along the first direction, the third width value of the third seam formed between two adjacent second LED display modules being equal to the first width value W1, and each second LED display module being prepared by the bright and dark line correction method between LED display modules described in the first aspect.

[0025] The beneficial effects of the method for correcting bright and dark lines between LED display modules and the LED display screen provided in this application are as follows: Compared with the prior art, the method for correcting bright and dark lines between LED display modules provided in this application firstly prepares a first LED display module using a predetermined process, and then compares the distance 2L1+W1 between two columns of first LED beads near the first seam formed after splicing two first LED display modules and the second distance L2 between two adjacent columns of first LED beads on the first LED display module. If If the ratio falls between the first predetermined ratio and the second predetermined ratio, it indicates that the first LED display module is less prone to bright and dark lines, and the prepared first LED display module can be used as a finished LED display module to meet usage requirements. >First predetermined ratio or If the second predetermined ratio is less than a certain value, it indicates that the first LED display module prepared is prone to bright and dark lines appearing at the splicing point after splicing. The first LED display module cannot meet the usage requirements and needs to be adjusted in terms of process or design parameters. Since the results after process adjustment are difficult to predict and control, the bright and dark line correction method between LED display modules provided in this application corrects the position of at least one column of first pads near the first side on the first printed circuit board without changing the manufacturing process of the printed circuit board and the soldering process of the LED beads. This is to prepare a second LED display module that is less prone to bright and dark lines after splicing. Specifically, for at least two columns of second pads near the second side on the second printed circuit board, the third distance L3 between the center of the column of second pads closest to the second side and the second side is between the first distance L1 and the second side. Between; and make the fourth distance L4 between any two adjacent second pads in any other column between the second distance L2 and 2L1+W1. After adopting the above design, when two second LED display modules are spliced ​​along the first direction and a third seam with a width equal to the first width value W1 is formed between them, the distance between the centers of any two adjacent columns of second pads in at least four columns closest to the third seam is between the second distance L2 and X1 (i.e., 2L1+W1). In this way, the maximum column spacing difference of multiple columns of second pads (column spacing refers to the distance between two adjacent columns of second pads, and column spacing difference refers to the difference between the spacings of two adjacent columns) is less than the absolute value of X1-L2, while the maximum column spacing difference of multiple columns of first pads is equal to the absolute value of X1-L2. Therefore, the maximum column spacing difference when two second LED display modules are spliced ​​along the first direction is smaller than the maximum column spacing difference when two first LED display modules are spliced ​​along the first direction. That is, the amplitude of the step change in column spacing is smaller, and bright and dark lines are less likely to appear at the third seam, which is beneficial to improving the display effect of the LED display screen. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 A flowchart illustrating a method for correcting bright and dark lines between LED display modules provided in some embodiments of this application;

[0028] Figure 2 This application provides schematic diagrams of the structures of two first LED display modules according to some embodiments;

[0029] Figure 3 for Figure 2 The exploded structural diagram of the two first LED display modules shown is shown below;

[0030] Figure 4 A top view of the structure of four first LED display modules provided in some embodiments of this application;

[0031] Figure 5 for Figure 4 Enlarged view at point A of the top view of the four first LED display modules shown;

[0032] Figure 6 This is a schematic diagram of the structure of two second LED display modules provided in some embodiments of this application;

[0033] Figure 7 for Figure 6 The exploded structural diagram of the two second LED display modules shown is shown.

[0034] Figure 8 A top view of four second LED printed circuit boards provided for some embodiments of this application;

[0035] Figure 9 for Figure 8 The enlarged view at point B of the top view of the four second LED printed circuit boards shown.

[0036] 100 - First LED display module; 110 - First printed circuit board; 111 - First substrate; 1111 - First side; 1112 - Third side; 112 - First solder pad; 120 - First LED bead; 101 - First seam; 102 - Second seam;

[0037] 200 - Second LED display module; 210 - Second printed circuit board; 211 - Second substrate; 2111 - Second side; 2112 - Fourth side; 212 - Second solder pad; 220 - Second LED bead; 201 - Third seam; 202 - Fourth seam;

[0038] L1 - First distance; L2 - Second distance; L3 - Third distance; L4 - Fourth distance; L5 - Fifth distance; L6 - Sixth distance; L7 - Seventh distance; L8 - Eighth distance; W1 - First width value; W2 - Second width value; W3 - Third width value; W4 - Fourth width value; X1 - First center distance; X2 - Second center distance; X3 - Third center distance; X4 - Fourth center distance. Detailed Implementation

[0039] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.

[0040] In the description of this application, it should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship 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 device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0041] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0042] In existing technologies, LED displays typically consist of multiple LED display modules spliced ​​together. Each LED display module usually includes a printed circuit board (PCB) and multiple LED beads mounted on the PCB. During the soldering process, such as reflow soldering, the LED display module undergoes significant temperature variations, causing its final dimensions to deviate from the design dimensions. This dimensional deviation can lead to situations where, after two LED display modules are spliced ​​together, the distance between the LED beads on either side of the seam is less than or greater than the distance between adjacent LED beads on a single LED display module. This results in bright or dark lines appearing at the seam between the two LED display modules. When the LED display plays videos or images, these bright or dark lines cause the displayed image to appear as a bright or dark grid, severely impacting the display's performance.

[0043] To address the aforementioned issues, this application provides a method for correcting bright and dark lines between LED display modules and an LED display screen. LED display modules prepared using this method are less prone to bright and dark lines appearing at the splicing points after splicing, which helps to ensure the display effect of the LED display screen.

[0044] Please see Figure 1 The method for correcting bright and dark lines between LED display modules provided in this application embodiment will now be described. The method for correcting bright and dark lines between LED display modules includes:

[0045] S1: Please refer to Figures 2 to 4 A first printed circuit board 110 is fabricated using a predetermined fabrication process. The first printed circuit board 110 includes a first substrate 111 and a plurality of first pads 112 arranged in rows on the first substrate 111. The first substrate 111 has two first sides 1111 that are disposed opposite each other in a first direction D1. The plurality of first pads 112 are centered between the two first sides 1111 and are arranged at equal intervals along the first direction D1.

[0046] S2: Please refer to Figure 2 and Figure 3 Multiple first LED beads 120 are soldered onto multiple first pads 112 using a predetermined soldering process to obtain a first LED display module 100.

[0047] S3: Please refer to Figure 5 The parameters are determined, including the first distance L1 between the first side 1111 on the first LED display module 100 and the center of the adjacent first LED lamp bead 120, and the second distance L2 between the centers of two adjacent columns of first LED lamp beads 120; and the first width value W1 of the first seam 101 formed when the two first LED display modules 100 are spliced ​​along the first direction D1 is determined.

[0048] It should be noted that you should refer to [link / reference]. Figure 5 In step S3 above, the first width value W1 can be a preset width value, which can be determined according to the size of the first LED display module 100 to ensure that the first LED display module 100 has sufficient expansion space. Of course, since there are often installation tolerances during the assembly of two first LED display modules 100, the actual width value of the first seam 101 between the two first LED display modules 100 after splicing may not be equal to the preset width value. Therefore, the two first LED display modules 100 can be installed using a predetermined installation process, and then the first width value W1 can be actually measured to improve the accuracy of the determined first width value W1. Furthermore, since the value of the first width W1 is usually small, the actual measurement requires high instrument accuracy, etc. Therefore, the first width W1 can be indirectly obtained by measuring the first center distance X1 between the centers of the two columns of first pads 112 on both sides of the first seam 101, and the first distance L1 between the first pad 112 on one side of the first seam 101 and the corresponding first side edge 1111, and then subtracting twice the first distance L1 from the first center distance X1. It is not necessary to directly measure the value of the first width W1. The appropriate method can be selected to determine the first width W1 as needed.

[0049] S4: If >First predetermined ratio or <The second predetermined ratio, i.e., >First predetermined ratio or If the second predetermined ratio is used, the second printed circuit board 210 will be fabricated using a predetermined fabrication process. Please refer to [link to relevant documentation]. Figures 6 to 8The second printed circuit board 210 includes a second substrate 211 and a plurality of second pads 212 arranged in rows on the second substrate 211. The second substrate 211 has two second sides 2111 disposed opposite each other in a first direction D1. The plurality of rows of second pads 212 are centered between the two second sides 2111 and are arranged sequentially at intervals along the first direction D1. Among at least two rows of second pads 212 near the same second side 2111, the third distance L3 between the center of the second pad 212 closest to the second side 2111 and the second side 2111 is between the first distance L1 and the second side 2111. Between; the fourth distance L4 between any two adjacent second pads 212 in any other column is between the second distance L2 and 2L1+W1.

[0050] This is understandable; please refer to [link / reference]. Figure 5 Two first LED display modules 100 are spliced ​​along a first direction D1, forming a first seam 101 between them. The first center distance between the centers of the two rows of first pads 112 located on both sides of the first seam 101 is X1, and X1 = 2L1 + W1. Please refer to Figure 9 Two second LED display modules 200 are spliced ​​along the first direction D1 and a third seam 201 with a width equal to the first width value W1 is formed between them. The third center distance between the centers of the two columns of second pads 212 located on both sides of the third seam 201 is X3, and X3 = 2L3 + W1.

[0051] It should be noted that in step S4 above, the first predetermined ratio is greater than 1. For example, the first predetermined ratio can be 102% to 108%, preferably 105%, 107%, etc. Thus, when... At the first predetermined ratio, that is, When the first predetermined ratio is reached, it can be determined that dark lines are prone to appear at the first seam 101 between the two first LED display modules 100, and the first LED display module 100 cannot meet the usage requirements. In this case, compared to the preparation of the first LED display module 100, the above step S4 adjusts the position of at least one row of second pads 212 near each second side 2111 of the second LED display module 200. Specifically, please refer to... Figure 9 The third distance L3 between the center of the second pad 212 closest to the second side 2111 and the second side 2111 is greater than 2111. And less than the first distance L1; and make the fourth distance L4 between any two adjacent columns of second pads 212 that need to be adjusted be greater than L2 and less than X1, so that when two second LED display modules 200 are spliced ​​together along the first direction D1 to form a third seam 201, the third center distance X3 and the fourth distance L4 can be greater than the second distance L2 and less than the first center distance X1.

[0052] Furthermore, in step S4 above, the second predetermined ratio is less than 1. For example, the second predetermined ratio can be 92% to 98%, preferably 95%, 97%, etc. When the second predetermined ratio is reached, that is, When the second predetermined ratio is used, bright lines are likely to appear at the first seam 101 between the two first LED display modules 100. In this case, compared to the fabrication of the first LED display module 100, step S4 above adjusts the position of at least one row of second pads 212 near each second side 2111 of the second LED display module 200. Specifically, please refer to... Figure 9 The third distance L3 between the center of the second pad 212 closest to the second side 2111 and the second side 2111 is greater than the first distance L1 and less than the first distance L1. Furthermore, the fourth distance L4 between any two adjacent columns of second pads 212 that require position adjustment is set to be greater than 2L1+W1 and less than L2. Thus, when two second LED display modules 200 are spliced ​​together along the first direction D1 to form a third seam 201, both the third center distance X3 and the fourth distance L4 are greater than the first center distance X1 and less than the second distance L2.

[0053] It should also be noted that in step S4, please refer to... Figure 8 For the other columns of second pads 212 that do not require position adjustment, the distance between two adjacent columns of second pads 212 remains at a second distance L2. In other words, for the second pads 212 on the second printed circuit board 210, in at least two columns of second pads 212 near the second side 2111, the distance between two adjacent columns of second pads 212 is a fourth distance L4, and for the other columns of second pads 212, the distance between two adjacent columns of second pads 212 remains at the second distance L2. The process method used to prepare the second printed circuit board 210 in step S4 is the same as the process method and parameters used to prepare the first printed circuit board 110 in step S1.

[0054] S5: Using a predetermined welding process, multiple second LED beads 220 are welded onto multiple first pads 112 respectively to obtain the finished second LED display module 200.

[0055] It is understood that the welding process used in step S5 to weld the second LED bead 220 is the same as the welding process and parameters used in step S2 to weld the first LED bead 120. Specifically, the welding process can be reflow soldering, and the welding temperature, solder type and other process parameters are the same.

[0056] The method for correcting bright and dark lines between LED display modules provided in this embodiment first prepares a first LED display module 100 using a predetermined process, and then compares the first center distance X1 between two rows of first LED beads 120 near the first seam 101 formed after splicing two first LED display modules 100 together with the second distance L2 between two adjacent rows of first LED beads 120 on the first LED display module 100. If If the ratio falls between the first predetermined ratio and the second predetermined ratio, it indicates that the first LED display module 100 is less prone to bright and dark lines, and the prepared first LED display module 100 can be used as a finished LED display module to meet usage requirements. >First predetermined ratio or If the second predetermined ratio is less than a certain value, it indicates that the first LED display module 100 prepared is prone to bright and dark lines appearing at the splicing point after splicing. The first LED display module 100 cannot meet the usage requirements, and adjustments need to be made to the process or design parameters of the first LED display module 100. Since the results after process adjustment are difficult to predict, the bright and dark line correction method between LED display modules provided in this application adjusts the position of at least one column of second pads 212 near the second side 2111 on the second printed circuit board 210 without changing the manufacturing process of the printed circuit board and the soldering process of the LED beads. This is to prepare a second LED display module 200 that is less prone to bright and dark lines after splicing. Specifically, among the several columns of second pads 212 near the second side 2111 on the second printed circuit board 210, the third distance L3 between the center of the column of second pads 212 closest to the second side 2111 and the second side 2111 is between the first distance L1 and the second side 2111. Between, and make the fourth distance L4 between any two adjacent second pads 212 in any other column between the second distance L2 and the first center distance X1.

[0057] After adopting the above design, when two second LED display modules 200 are spliced ​​together and a third seam 201 with a width equal to the first width value W1 is formed between them, in at least four columns of second pads 212 closest to the third seam 201, the distance between the centers of any two adjacent columns of second pads 212 is between the second distance L2 and the first center distance X1. In this way, the maximum column spacing difference of multiple columns of second pads 212 (column spacing refers to the distance between two adjacent columns of second pads 212, and column spacing difference refers to the distance between adjacent columns of second pads 212) is maximized. The difference between the two column spacings is less than the absolute value of X1-L2, while the maximum column spacing difference of the first pads 112 is equal to the absolute value of X1-L2. Therefore, the maximum column spacing difference when two second LED display modules 200 are spliced ​​along the first direction D1 is smaller than the maximum column spacing difference when two first LED display modules 100 are spliced ​​along the first direction D1. That is, the magnitude of the step change in column spacing is smaller, and it is less likely to appear bright and dark lines at the third seam 201, which is beneficial to improving the display effect of the LED display screen.

[0058] Please see Figure 9 In some embodiments, for N+1 columns of second pads 212 adjacent to the same second side 2111, the third distance L3 is equal to The fourth distance L4 equals Where N is a positive integer greater than or equal to 1.

[0059] Specifically, for the N+1 columns of second pads 212 located on one side of the third seam 201 and the N+1 columns of second pads 212 located on the other side of the third seam 201, the distance between the centers of any two adjacent columns of second pads 212 is equal to...

[0060] In the technical solution provided in this embodiment, after the two second LED display modules 200 are spliced ​​along the first direction D1, the 2N+2 columns of second pads 212 near the third seam 201 are evenly arranged, and the maximum column spacing difference is [value missing]. The maximum column spacing difference 2L1+W1-L2 after splicing two first LED display modules of 100 is given. The maximum column spacing difference after splicing two second LED display modules 200 along the first direction D1 is much smaller than the maximum column spacing difference after splicing two first LED display modules 100 along the first direction D1. The magnitude of the step change in column spacing when splicing two second LED display modules 200 along the first direction D1 is smaller, which can effectively reduce the probability of bright and dark lines appearing at the third seam 201.

[0061] As N increases, the maximum column spacing difference increases. A smaller N value helps avoid bright and dark lines, but a larger N value requires adjusting the number of columns of the second pad 212, increasing the cost of the second LED display module 200. Therefore, a suitable N value can be chosen to balance the display effect and the cost of the second LED display module 200. Specifically, when the total number of columns of the second pad 212 is 8, N can be 2.

[0062] For example, taking N as 1, please refer to Figure 5 If, after the first LED display module 100 is spliced, the first center distance X1 between the centers of the two columns of first LED beads 120 on both sides of the first splice 101 is 1.35mm, the second distance L2 between the centers of two adjacent columns of LED beads on the same LED display module is 1.5mm, the first distance L1 between the first side 1111 and the center of the adjacent first LED bead 120 is 0.6mm, and the first width W1 of the first splice 101 is 0.15mm.

[0063] Please refer to 8 and Figure 9 When the second printed circuit board 210 is prepared using the above step S4, the third distance L3 between the center of the second pad 212 closest to the second side 2111 and the second side 2111, the third center distance X3 between the centers of the two rows of second pads 212 on both sides of the third seam 201, and the fourth distance L4 can be taken according to the following formulas:

[0064]

[0065] X3=2L3+W1=2×0.06+0.15=1.45mm

[0066]

[0067] Therefore, after adjusting the row of second pads 212 near the second side 2111 on the second LED display module 200 according to step S4 above, the maximum column spacing difference after splicing the two second LED display modules 200 is equal to 1.5mm minus 1.45mm, which is equal to 0.05mm. The maximum column spacing difference after splicing the two first LED display modules 100 is equal to 1.5mm-1.35mm, which is equal to 0.15mm. It can be seen that the maximum column spacing difference after splicing the two second LED display modules 200 is less than the maximum column spacing difference after splicing the two first LED display modules 100. Therefore, it is less likely for bright and dark lines to form at the splicing point after splicing the two second LED display modules 200.

[0068] In some embodiments, The absolute value is less than 5% of the second distance L2.

[0069] As mentioned earlier, after splicing two second LED display modules 200, the maximum column spacing difference is equal to In the technical solution provided in this embodiment, the maximum column spacing difference is... By limiting the distance to less than 5% of the second distance L2, the magnitude of the abrupt change in column spacing can be limited to a small range, thereby ensuring that no bright or dark line is formed at the third seam 201 after the second LED display module 200 is spliced.

[0070] In some embodiments, the second substrate 211 and the first substrate 111 have the same coefficient of thermal expansion; the second pad 212 and the first pad 112 have the same coefficient of thermal expansion; and the second LED bead 220 and the first LED bead 120 have the same coefficient of thermal expansion. This configuration reduces the differences between the first LED display module 100 and the second LED display module 200 during the manufacturing process, making the position of the second pad 212 the only variable affecting the position of the second LED bead 220. This facilitates adjusting the position of the second LED bead 220 as expected after adjusting the position of the second pad 212.

[0071] In some embodiments, please refer to Figure 8 The first substrate 111 also has two third sides 1112 disposed opposite to each other in the second direction D2, and multiple rows of first pads 112 are centered between the two third sides 1112 and are arranged at equal intervals along the second direction D2, the second direction D2 being perpendicular to the first direction D1.

[0072] Please see Figure 5 The "determine parameters" step also includes: determining the fifth distance L5 between the center of the first LED bead 120 near the third side 1112 and the adjacent third side 1112; determining the sixth distance L6 between the centers of two adjacent rows of first LED beads 120 on the same first LED display module 100; and determining the second width value W2 of the second seam 102 where the two first LED display modules 100 are spliced ​​together along the second direction D2.

[0073] Please see Figure 8 and Figure 9 In the step of “preparing the second printed circuit board 210 using a predetermined preparation process”, the second substrate 211 has two fourth sides 2112 disposed opposite to each other in the second direction D2, and multiple rows of second pads 212 are centered between the two fourth sides 2112 and are arranged at equal intervals along the second direction D2.

[0074] The step of "fabricating the second printed circuit board 210 using a predetermined fabrication process" also includes: if >Third predetermined ratio or <The fourth predetermined ratio, then among at least two rows of second pads 212 close to the same fourth side 2112, the seventh distance L7 between the center of the second pad 212 closest to the fourth side 2112 and the fourth side 2112 is between the fifth distance L5 and the fourth side 2112. The eighth distance L8 between any two adjacent rows of second pads 212 is between the sixth distance L6 and 2L5+W2.

[0075] It can be understood that two first LED display modules 100 are spliced ​​along the second direction D2 to form a second seam 102. The second center distance between the centers of the two rows of first pads 112 on both sides of the second seam 102 is X2, and X2 = 2L5 + W2. Two second LED display modules 200 are spliced ​​along the second direction D2 to form a fourth seam 202. The fourth width value W4 of the fourth seam 202 is equal to the second width value W2. The fourth center distance between the centers of the two rows of second pads 212 on both sides of the fourth seam 202 is X4, and X4 = 2L7 + W2.

[0076] It should be noted that you should refer to [link / reference]. Figure 5 The third predetermined ratio is greater than 1, for example, the third predetermined ratio can be 102% to 108%, preferably 105%, 107%, etc., so that when >At the third predetermined ratio, that is, When the third predetermined ratio is used, it can be determined that dark lines are likely to appear at the second seam 102 between the two first LED display modules 100. In this case, step S4 above adjusts the position of at least one row of second pads 212 near each third side 1112. Specifically, please refer to Figure 9 Step S4 above ensures that, after adjustment, the seventh distance L7 between the center of the second pad 212 closest to the fourth side 2112 and the fourth side 2112 is greater than... And less than the fifth distance L5; and make the eighth distance L8 between any two adjacent rows of second pads 212 that need to be adjusted satisfy that is greater than the sixth distance L6 and less than the second center distance X2, so that the fourth center distance X4 and the eighth distance L8 are both greater than the sixth distance L6 and less than the second center distance X2.

[0077] In step S4 above, please refer to Figure 5 The fourth predetermined ratio is less than 1, for example, the fourth predetermined ratio can be 92% to 98%, preferably 95%, 97%, etc. When the fourth predetermined ratio is reached, that is, <The fourth predetermined ratio indicates that bright lines are likely to appear at the second seam 102 between the two first LED display modules 100. In this case, step S4 above adjusted the position of at least one row of second pads 212 near each second side 2111. Specifically, please refer to Figure 9 After the adjustment is completed in step S4, the seventh distance L7 between the center of the second pad 212 closest to the fourth side 2112 and the fourth side 2112 is greater than the fifth distance L5 and less than the fifth distance L5. And make the eighth distance L8 between any two adjacent rows of second pads 212 that need to be repositioned be greater than the second center distance X2 and less than the sixth distance L6. In this way, the fourth center distance X4 and the eighth distance L8 are both greater than the second center distance X2 and less than the sixth distance L6.

[0078] In the technical solution provided in this embodiment, when two second LED display modules 200 are spliced ​​together to form a fourth seam 202 with a width equal to the second width value W2, the distance between the centers of any two adjacent rows of second pads 212 in the at least four rows closest to the fourth seam 202 is between the sixth distance L6 and the second center distance X2. This makes the maximum line spacing difference of multiple rows of second pads 212 (line spacing refers to the distance between two adjacent rows of second pads 212, and the line spacing difference refers to the difference between two adjacent line spacings) less than the absolute value of X2-L6. The maximum line spacing difference of multiple rows of first pads 112 is equal to the absolute value of X2-L6. Therefore, compared with the splicing of two first LED display modules 100, the maximum line spacing difference is smaller when two second LED display modules 200 are spliced ​​together, that is, the amplitude of the step change in line spacing is smaller. Bright and dark lines are less likely to appear at the fourth seam 202, which is beneficial to improving the display effect of the LED display screen.

[0079] Please see Figure 1 and Figure 2 In some embodiments, for the second pad 212 in row M+1 near the same third side 1112, the seventh distance L7 is equal to The eighth distance L8 equals Where M is a positive integer greater than or equal to 1. The value of M can be equal to N or not equal to N.

[0080] Specifically, for the M+1 row second pads 212 located on one side of the fourth seam 202 and the M+1 row second pads 212 located on the other side of the fourth seam 202, the distance between the centers of any two adjacent rows of the 2M+2 rows of second pads 212 is equal to...

[0081] In the technical solution provided in this embodiment, after the two second LED display modules 200 are spliced ​​together, the 2M+2 rows of second pads 212 near the fourth seam 202 are evenly arranged, and the maximum row spacing difference is [value missing]. The maximum column spacing difference after splicing two first LED display modules (100 each) is 2L5+W2-L6. The maximum line spacing difference has been significantly reduced, and the magnitude of the step change in line spacing is smaller, which can effectively reduce the probability of bright and dark lines appearing at the fourth seam 202.

[0082] In some embodiments, The absolute value is less than 5% of the sixth distance L6.

[0083] As mentioned earlier, after splicing two second LED display modules 200, the maximum line spacing difference is equal to In the technical solution provided in this embodiment, the maximum line spacing difference is... By limiting it to less than 5% of the sixth distance L6, the magnitude of the row spacing step change can be limited to a small range, thereby ensuring that no bright or dark line is formed at the fourth seam 202 after the second LED display module 200 is spliced.

[0084] Please see Figure 6 and Figure 7 This application also provides an LED display screen, which includes at least two second LED display modules 200 spliced ​​together along a first direction D1. The third width value W3 of the third seam 201 formed between two adjacent second LED display modules 200 is equal to the first width value W1. Each second LED display module 200 is prepared by the above-mentioned method for correcting bright and dark lines between LED display modules.

[0085] The LED display screen provided in this embodiment has a second LED display module 200 prepared by the above-mentioned method for correcting bright and dark lines between LED display modules. Therefore, after the two second LED display modules 200 are spliced ​​along the first direction D1, bright and dark lines are not likely to appear at the splicing point, which can ensure that the LED display screen has a better display effect.

[0086] Furthermore, there is a third seam 201 between two adjacent second LED display modules 200, which can reserve a certain space for thermal expansion and contraction, and can minimize the situation where the second LED display modules 200 are easily squeezed against each other due to thermal expansion.

[0087] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A method for correcting bright and dark lines between LED display modules, characterized in that, Methods for correcting bright and dark lines between LED display modules include: A first printed circuit board is fabricated using a predetermined fabrication process. The first printed circuit board includes a first substrate and a plurality of first pads arranged in rows and columns on the first substrate. The first substrate has two first sides that are disposed opposite each other in a first direction. The plurality of first pads are centered between the two first sides and are arranged at equal intervals along the first direction. Multiple first LED beads are soldered onto multiple first pads using a predetermined soldering process to obtain a first LED display module; Determine the parameters, including the first distance L1 between the first side of the first LED display module and the center of the adjacent first LED bead, and the second distance L2 between the centers of two adjacent columns of first LED beads; and determine the first width value W1 of the first seam formed when the two first LED display modules are spliced ​​together along the first direction. like >First predetermined ratio or If the second predetermined ratio is specified, then the predetermined manufacturing process is used to fabricate a second printed circuit board. The second printed circuit board includes a second substrate and a plurality of second pads arranged in rows and columns on the second substrate. The second substrate has two second sides disposed opposite to each other in the first direction. The plurality of rows of second pads are centered between the two second sides and are arranged sequentially at intervals along the first direction. In at least two rows of second pads near the same second side, the third distance L3 between the center of the second pad closest to the second side and the second side is between the first distance L1 and L2. Between; the fourth distance L4 between any two adjacent second pads in any other column is between the second distance L2 and L4. Between 1 and W1; wherein the first predetermined ratio is between 102% and 108%; and the second predetermined ratio is between 92% and 98%. Multiple second LED beads are soldered onto multiple first pads using the predetermined welding process to obtain the finished second LED display module.

2. The method for correcting bright and dark lines between LED display modules according to claim 1, characterized in that, For the N+1 columns of second pads adjacent to the same second side, the third distance L3 is equal to The fourth distance L4 is equal to .

3. The method for correcting bright and dark lines between LED display modules according to claim 2, characterized in that, The absolute value is less than 5% of the second distance L2.

4. The method for correcting bright and dark lines between LED display modules according to claim 1, characterized in that, The second substrate and the first substrate have the same coefficient of thermal expansion; the second pad and the first pad have the same coefficient of thermal expansion; the second LED bead and the first LED bead have the same coefficient of thermal expansion.

5. The method for correcting bright and dark lines between LED display modules according to claim 1, characterized in that, The first substrate also has two third sides disposed opposite each other in a second direction, and multiple rows of first pads are centered between the two third sides and are arranged at equal intervals along the second direction, the second direction being perpendicular to the first direction; The "determine parameters" step further includes: determining the fifth distance L5 between the third side of the first LED display module and the center of the adjacent first LED lamp bead, and the sixth distance L6 between the centers of two adjacent rows of first LED lamp beads; and determining the second width value W2 of the second seam where the two first LED display modules are spliced ​​together along the second direction; In the step of "preparing a second printed circuit board using the predetermined preparation process", the second substrate has two fourth sides that are disposed opposite to each other in the second direction, and multiple rows of the second pads are centered between the two fourth sides and are arranged at intervals along the second direction. The step of "fabricating the second printed circuit board using the predetermined fabrication process" further includes: if >Third predetermined ratio or If the fourth predetermined ratio is less than a certain value, then the seventh distance L7 between the center of the second pad closest to the fourth side and the fourth side is between the fifth distance L5 and the fourth side. Between; the eighth distance L8 between any two adjacent rows of the second pads is between the sixth distance L6 and... Between 5 and W2; wherein the third predetermined ratio is 102% to 108%; and the fourth predetermined ratio is 92% to 98%.

6. The method for correcting bright and dark lines between LED display modules according to claim 5, characterized in that, For the second pad in row M+1 that is close to the same third side, the seventh distance L7 is equal to The eighth distance L8 is equal to .

7. The method for correcting bright and dark lines between LED display modules according to claim 5, characterized in that, The absolute value is less than 5% of the sixth distance L6.

8. An LED display screen, characterized in that, The LED display screen includes at least two second LED display modules spliced ​​together along the first direction. The third width value W3 of the third seam formed between two adjacent second LED display modules is equal to the first width value W1. Each second LED display module is prepared by the bright and dark line correction method between LED display modules according to any one of claims 1-7.

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