LED display screen unit module correction method

Abstract

The invention relates to an LED display screen unit module correction method, which comprises the following steps of: building an LED display array, and obtaining a'flat-like 'matrix of each pixel point in the LED display array; solving a lens vignetting correction matrix by using the'flat-like 'matrix and the normalized original tristimulus value matrix of each pixel point of the display unit in the dead center area of the display array; for batch unit modules, multiplying the original tristimulus value matrix of each pixel point in each module by the lens vignetting correction matrix to obtain a flat tristimulus value matrix, calculating a brightness and chrominance correction coefficient, and completing brightness and chrominance correction of each unit module; the method is simple and easy to implement, the correction matrix is not influenced by the change of camera lens parameters, and the problem of'bright edge 'generated by correction of the traditional unit module is not caused by considering the foil influence of the pixel points at the upper, lower, left and right edges of the unit module.

Description

Technical field:

[0001] The invention belongs to the technical field of LED display screen correction, and in particular relates to a method for correcting a unit module of an LED display screen. Background technology:

[0002] Due to the discreteness of the LED display chip, in order to ensure high-quality display, it needs to be calibrated point by point. Currently, there are two commonly used calibration methods: full-screen calibration and production-line-level unit module / module calibration. Due to the physical limitations of the lens elements of the camera used for calibration, the brightness of the edge or corner of the image will be lower than that of the central area, forming a transition of decreasing brightness from the center to the edge. This problem will cause brightness jumps in each module and at the module joints during the display unit acquisition process, affecting the effect after calibration. The currently commonly used method of correcting camera lens vignetting is acceptable for the transition during full-screen calibration, but when calibrating a single module or module, due to the small module area and too many joints, the human eye can recognize subtle brightness jumps, and conventional vignetting correction methods often have unsatisfactory effects on unit calibration. Summary of the invention:

[0003] The technical problem to be solved by the present invention is to provide a method for calibrating a unit module of an LED display screen, which can eliminate the splicing "curved surface effect" caused by the vignetting of the camera lens after the unit module of the LED display screen is calibrated, and improve the brightness and color consistency of the unit module splicing.

[0004] In order to solve the above technical problems, the LED display unit module calibration method of the present invention is as follows:

[0005] Step 1: Build an LED display array with m*n box structures, 2≤m, n≤5; place the camera in front of the LED display array, collect the brightness and chromaticity of the entire array at one time, obtain the tristimulus value matrix of each pixel in the LED display array, and then calibrate the entire array to obtain a "quasi-flat" matrix of each pixel;

[0006] Step 2: intercept the “quasi-flat” matrix of each pixel point of t display units in the center area of ​​the LED display array, t≤4; for any pixel point q in the i-th display unit, its “quasi-flat” matrix is ​​expressed as: RX i-q RY i-q , RZ i-q , GX i-q , GY i-q , GZ i-q , BX i-q 、BY i-q , BZ i-q , i = 1 ~ t;

[0007] Step 3: Remove t display units in the center area of ​​the LED display array, and use the automated calibration equipment to collect brightness and chromaticity separately in turn to obtain the original three-stimulus value matrix of each pixel of each display unit; normalize the data obtained by the brightness and chromaticity collection of the entire array and the brightness and chromaticity collection of the display unit; for any pixel q in the i-th display unit, its normalized original three-stimulus value matrix is ​​expressed as: RX'm i-q RY'm i-q 、RZ'm i-q 、GX'm i-q , GY'm i-q 、GZ'm i-q 、BX'm i-q 、BY'm i-q 、BZ'm i-q , where i = 1 ~ t;

[0008] Step 4: Use the "quasi-flattened" matrix of each pixel in the t display units in the center area and the normalized original three stimulus value matrix to obtain the lens vignetting correction matrix, which is expressed as: Fix_RX, Fix_RY, Fix_RZ, Fix_GX, Fix_GY, Fix_GZ, Fix_BX, Fix_BY, Fix_BZ;

[0009] Fix_RX=(RX 1-q / RX'm 1-q +RX 2-q / RX'm 2-q +RX 3-q / RX'm 3-q +RX 4- q / RX'm 4-q ) / 4

[0010] Fix_RY=(RY 1-q / RY'm 1-q +RY 2-q / RY'm 2-q +RY 3-q / RY'm 3-q +RY 4-q / RY'm 4-q ) / 4

[0011] Fix_RZ=(RZ 1-q / RZ'm 1-q +RZ 2-q / RZ'm 2-q +RZ 3-q / RZ'm 3-q +RZ 4-q / RZ'm 4-q ) / 4

[0012] Fix_GX=(GX 1-q / GX’m 1-q +GX 2-q / GX’m 2-q +GX 3-q / GX’m 3-q +GX 4-q / GX’m 4-q ) / 4

[0013] Fix_GY=(GY 1-q / GY’m 1-q +GY 2-q / GY’m 2-q +GY 3-q / GY’m 3-q +GY 4-q / GY’m 4-q ) / 4

[0014] Fix_GZ=(GZ 1-q / GZ’m 1-q +GZ 2-q / GZ’m 2-q +GZ 3-q / GZ’m 3-q +GZ 4-q / GZ’m 4-q ) / 4

[0015] Fix_BX=(BX 1-q / BX’m 1-q +BX 2-q / BX’m 2-q +BX 3-q / BX’m 3-q +BX 4-q / BX’m 4-q ) / 4

[0016] Fix_BY=(BY 1-q / BY’m 1-q +BY 2-q / BY’m 2-q +BY 3-q / BY’m 3-q +BY 4-q / BY’m 4-q ) / 4

[0017] Fix_BZ=(BZ 1-q / BZ’m 1-q +BZ 2-q / BZ’m 2-q +BZ 3-q / BZ’m 3-q +BZ 4-q / BZ’m 4-q) / 4

[0018] Step 5: Use automated correction equipment to collect brightness and chromaticity of batch unit modules separately to obtain the original three-stimulus value matrix of each pixel of each unit module; for any pixel, multiply the original three-stimulus value matrix of the pixel by the lens vignetting correction matrix to obtain its flat three-stimulus value matrix, use the flat three-stimulus value matrix to calculate its brightness and chromaticity correction coefficient, and use the obtained brightness and chromaticity correction coefficient of each pixel to complete the brightness and chromaticity correction of each unit module.

[0019] Furthermore, the display unit is a unit module.

[0020] Furthermore, the display unit is an h×w unit module, where h is the number of rows of modules in the unit module, and w is the number of columns of modules in the unit module, and h=1-3 and w=1-2.

[0021] Beneficial effect: The present invention uses the "quasi-flat" matrix of each pixel point of t display units in the center area of ​​the LED display array and the normalized original three-stimulus value matrix to obtain the lens vignetting correction matrix; since these t display units are located in the center of the camera lens, the vignetting is small and the "quasi-flat" matrix is ​​obtained through the correction algorithm, which can be considered "absolutely flat". The lens vignetting correction matrix is ​​obtained by dividing the absolute flat plane by the normalized original three-stimulus value matrix, thereby obtaining the brightness chromaticity correction coefficient of each pixel point of the batch unit module to complete the brightness chromaticity correction of each unit module. The method is simple and easy to implement, and the change of camera lens parameters will not affect the correction matrix. In addition, the contrast effect of the upper, lower, left and right edge pixels of the unit module is taken into account, and the "bright edge" problem caused by the traditional unit module correction will not be caused. Description of the drawings:

[0022] Figure 1 It is a flow chart of the present invention.

[0023] Figure 2 This is a diagram showing the arrangement of the LED display array unit modules in Example 1 of the present invention.

[0024] Figure 3 This is a diagram showing the arrangement of the LED display array unit modules in Example 2 of the present invention.

[0025] Figure 4 This is the correction coefficient diagram of the front unit module of the uncorrected camera vignetting.

[0026] Figure 5 This is a correction coefficient diagram of the rear unit module after correcting camera vignetting using the present invention. Specific implementation method:

[0027] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention rather than to limit the present invention.

[0028] Embodiment 1:

[0029] like Figure 1 As shown, the specific steps of the LED display unit module correction method of the present invention are as follows:

[0030] Step 1, build an LED display array with m*n box structures. Theoretically, the LED display array is the array area that the camera can calibrate at one time. Building too many boxes consumes manpower and time. It is generally recommended to build an LED display array with 3*3 or 4*4 box structures. Generally, 2≤m, n≤5. This embodiment builds an LED display array consisting of 3 rows and 3 columns of boxes. The LED display array is composed of 12 unit modules horizontally and 6 unit modules vertically, with a total of 72 unit modules; the camera is placed in front of the LED display array to collect the brightness and chromaticity of the entire array at one time. The camera is equipped with a CIE-XYZ filter to obtain the XYZ tristimulus values ​​of the red, green and blue light-emitting tube cores. After collecting the brightness and color of the entire array, the red, green and blue tristimulus value matrix of each pixel in the LED display array is obtained, and then the entire array is corrected using conventional surface fitting or lens vignetting correction algorithms to obtain a "quasi-flat" matrix for each pixel. Quasi-flat means that the middle area of ​​the matrix is ​​flat, and there are still uneven areas around it after correction due to the large lens distortion. For any pixel p, its "quasi-flat" matrix is ​​expressed as: RX p RY p , RZ p , GX p , GY p , GZ p , BX p 、BY p , BZ p .

[0031] Step 2: Figure 2 As shown, the “quasi-flat” matrix of each pixel point of the four unit modules 1, 2, 3, and 4 in the center area of ​​the LED display array is intercepted; for any pixel point q in the i-th unit module, its “quasi-flat” matrix is ​​expressed as: RX i-q RY i-q , RZ i-q , GX i-q , GY i-q , GZ i-q , BX i-q 、BY i-q , BZ i-q , where i=1~4.

[0032] Step 3: Use the automated calibration equipment to collect the brightness and chromaticity of the four unit modules 1, 2, 3, and 4 in the center of the LED display array, and obtain the original three-stimulus value matrix of each pixel point of each unit module. No camera vignetting correction is performed here. For any pixel point q in the i-th unit module, its original three-stimulus value matrix is ​​expressed as: RXm i-q RYm i-q , RZm i-q , GXm i-q , GYm i-q , GZm i-q , BXm i-q 、BYm i-q , BZm i-q , where i=1~4; the automated correction equipment adopts the existing wire picking machine.

[0033] Due to the different settings of the lens parameters, exposure time, etc. of the camera and the automatic calibration equipment when collecting the brightness and chromaticity of the entire array and the brightness and chromaticity of the unit module, the obtained data will be quite different. It is necessary to normalize the two and compare them at the same order of magnitude. For any pixel point q in the i-th unit module, its normalized original three stimulus value matrix is ​​expressed as: RX'm i-q RY'm i-q 、RZ'm i-q 、GX'm i-q , GY'm i-q 、GZ'm i-q 、BX'm i-q 、BY'm i-q 、BZ'm i-q , where i = 1 to 4;

[0034] Step 4, using the "quasi-flattened" matrix of each pixel point in the four unit modules in the center area and the normalized original three stimulus value matrix, the lens vignetting correction matrix is ​​obtained, which is expressed as: Fix_RX, Fix_RY, Fix_RZ, Fix_GX, Fix_GY, Fix_GZ, Fix_BX, Fix_BY, Fix_BZ;

[0035] Fix_RX=(RX 1-q / RX'm 1-q +RX 2-q / RX'm 2-q +RX 3-q / RX'm 3-q +RX 4- q / RX'm 4-q ) / 4

[0036] Fix_RY=(RY 1-q / RY'm1-q +RY 2-q / RY’m 2-q +RY 3-q / RY’m 3-q +RY 4-q / RY’m 4-q ) / 4

[0037] Fix_RZ=(RZ 1-q / RZ’m 1-q +RZ 2-q / RZ’m 2-q +RZ 3-q / RZ’m 3-q +RZ 4-q / RZ’m 4-q ) / 4

[0038] Fix_GX=(GX 1-q / GX’m 1-q +GX 2-q / GX’m 2-q +GX 3-q / GX’m 3-q +GX 4-q / GX’m 4-q ) / 4

[0039] Fix_GY=(GY 1-q / GY’m 1-q +GY 2-q / GY’m 2-q +GY 3-q / GY’m 3-q +GY 4-q / GY’m 4-q ) / 4

[0040] Fix_GZ=(GZ 1-q / GZ’m 1-q +GZ 2-q / GZ’m 2-q +GZ 3-q / GZ’m 3-q +GZ 4-q / GZ’m 4-q ) / 4

[0041] Fix_BX=(BX 1-q / BX’m 1-q +BX 2-q / BX’m 2-q +BX 3-q / BX’m 3-q +BX 4-q / BX’m 4-q ) / 4

[0042] Fix_BY=(BY 1-q / BY'm 1-q +BY 2-q / BY'm 2-q +BY 3-q / BY'm 3-q +BY 4-q / BY'm 4-q ) / 4

[0043] Fix_BZ=(BZ 1-q / BZ'm 1-q +BZ 2-q / BZ'm 2-q +BZ 3-q / BZ'm 3-q +BZ 4-q / BZ'm 4-q ) / 4

[0044] Step 5: Use the automated calibration equipment to collect brightness and chromaticity of the batch unit modules separately to obtain the original three-stimulus value matrix of each pixel point of each unit module; for the pixel point p on any unit module k, its original three-stimulus value matrix is ​​expressed as: RXm k-q RYm k-q , RZm k-q , GXm k-q , GYm k-q , GZm k-q , BXm k-q 、BYm k-q , BZm k-q ; Multiply the original three-stimulus value matrix of the pixel by the lens vignetting correction matrix Fix to obtain its flat three-stimulus value matrix, expressed as: RXFixm k-q RYFixm k-q 、RZFixm k-q 、GXFixm k-q 、GYFixm k-q 、GZFixm k-q 、BXFixm k-q BYFixm k-q 、BZFixm k-q The brightness and chromaticity correction coefficients of the flattened tristimulus value matrix can be calculated according to conventional methods, and the brightness and chromaticity correction of each unit module can be completed using the obtained brightness and chromaticity correction coefficients of each pixel point; the brightness and chromaticity correction coefficients of each pixel point in each unit module can be downloaded to the unit module flash for brightness and chromaticity correction, or the unit modules whose brightness and chromaticity correction coefficients of each pixel point are obtained by the above method can be used to assemble and build an LED display screen, and then the brightness and chromaticity correction coefficients of each pixel point can be downloaded to the whole screen flash to complete the brightness and chromaticity correction of the entire LED display screen.

[0045] RXFixm k-q =Fix_RX*RXm k-q

[0046] RYFixm k-q =Fix_RY*RYm k-q

[0047] RZFix k-q =Fix_RZ*RZm k-q

[0048] GXFixm k-q =Fix_GX*GXm k-q

[0049] GYFixm k-q =Fix_GY*GYm k-q

[0050] GZFix k-q =Fix_GZ*GZm k-q

[0051] BXFixm k-q =Fix_BX*BXm k-q

[0052] BYFixm k-q =Fix_BY*BYm k-q

[0053] BZFixm k-q =Fix_BZ*BZm k-q

[0054] Embodiment 2:

[0055] The specific steps of the LED display unit module correction method of the present invention are as follows:

[0056] Step 1. Build an LED display array consisting of 5 rows and 4 columns of boxes. The LED display array consists of 10 modules horizontally and 4 modules vertically. There are 40 unit modules in total, and each unit module contains 3 rows and 2 columns of unit modules. After collecting the brightness and chromaticity of the entire array, the red, green and blue three-stimulus value matrix of each pixel in the LED display array is obtained, and then the entire array is corrected using conventional surface fitting or lens vignetting correction algorithms to obtain a "quasi-flat" matrix for each pixel; for any pixel p, its "quasi-flat" matrix is ​​expressed as: RX p RY p , RZ p , GX p , GY p , GZ p , BXp 、BY p , BZ p .

[0057] Step 2: Figure 3 As shown, the “quasi-flat” matrix of each pixel point of the two unit modules 5 and 6 in the center area of ​​the LED display array is intercepted; for any pixel point q in the i-th unit module, its “quasi-flat” matrix is ​​expressed as: RX i-q RY i-q , RZ i-q , GX i-q , GY i-q , GZ i-q , BX i-q 、BY i-q , BZ i-q , where i=1~2.

[0058] Step 3: Use the automated calibration equipment to collect brightness and chromaticity of the two unit modules in the center area 5 and 6 of the display array in turn, and obtain the original three-stimulus value matrix of each pixel point of the two unit modules. For any pixel point q in the i-th unit module, its original three-stimulus value matrix is ​​expressed as: RXm i-q RYm i-q , RZm i-q , GXm i-q , GYm i-q , GZm i-q , BXm i-q 、BYm i-q , BZm i-q , where i = 1 to 2; the data obtained by the camera and the automatic calibration equipment are normalized; for any pixel point q in the i-th unit module, its normalized original three stimulus value matrix is ​​expressed as: RX'm i-q RY'm i-q 、RZ'm i-q 、GX'm i-q , GY'm i-q 、GZ'm i-q 、BX'm i-q 、BY'm i-q 、BZ'm i-q , where i = 1 to 2;

[0059] Step 4, using the "quasi-flattened" matrix of each pixel point in the two unit modules in the center area 5 and 6 and the normalized original three stimulus value matrix, the lens vignetting correction matrix is ​​obtained, which is expressed as: Fix_RX, Fix_RY, Fix_RZ, Fix_GX, Fix_GY, Fix_GZ, Fix_BX, Fix_BY, Fix_BZ;

[0060] Fix_RX=(RX 1-q / RX’m 1-q +RX 2-q / RX’m 2-q +RX 3-q / RX’m 3-q +RX 4- q / RX’m 4-q ) / 4

[0061] Fix_RY=(RY 1-q / RY’m 1-q +RY 2-q / RY’m 2-q +RY 3-q / RY’m 3-q +RY 4-q / RY’m 4-q ) / 4

[0062] Fix_RZ=(RZ 1-q / RZ’m 1-q +RZ 2-q / RZ’m 2-q +RZ 3-q / RZ’m 3-q +RZ 4-q / RZ’m 4-q ) / 4

[0063] Fix_GX=(GX 1-q / GX’m 1-q +GX 2-q / GX’m 2-q +GX 3-q / GX’m 3-q +GX 4-q / GX’m 4-q ) / 4

[0064] Fix_GY=(GY 1-q / GY’m 1-q +GY 2-q / GY’m 2-q +GY 3-q / GY’m 3-q +GY 4-q / GY’m 4-q ) / 4

[0065] Fix_GZ=(GZ 1-q / GZ’m 1-q +GZ 2-q / GZ’m 2-q +GZ 3-q / GZ’m 3-q +GZ 4-q / GZ’m4-q ) / 4

[0066] Fix_BX=(BX 1-q / BX'm 1-q +BX 2-q / BX'm 2-q +BX 3-q / BX'm 3-q +BX 4-q / BX'm 4-q ) / 4

[0067] Fix_BY=(BY 1-q / BY'm 1-q +BY 2-q / BY'm 2-q +BY 3-q / BY'm 3-q +BY 4-q / BY'm 4-q ) / 4

[0068] Fix_BZ=(BZ 1-q / BZ'm 1-q +BZ 2-q / BZ'm 2-q +BZ 3-q / BZ'm 3-q +BZ 4-q / BZ'm 4-q ) / 4

[0069] Step 5: Use the automated calibration equipment to collect brightness and chromaticity of the batch unit modules separately to obtain the original three-stimulus value matrix of each pixel point of each unit module; for the pixel point p on any unit module k, its original three-stimulus value matrix is ​​expressed as: RXm k-q RYm k-q , RZm k-q , GXm k-q , GYm k-q , GZm k-q , BXm k-q 、BYm k-q , BZm k-q ; Multiply the original three-stimulus value matrix of the pixel by the lens vignetting correction matrix Fix to obtain its flat three-stimulus value matrix, expressed as: RXFixm k-q RYFixm k-q 、RZFixm k-q 、GXFixm k-q 、GYFixm k-q 、GZFixm k-q 、BXFixm k-q BYFixm k-q 、BZFixmk-q The brightness and chromaticity correction coefficients of the flattened tristimulus value matrix can be calculated according to conventional methods, and the brightness and chromaticity correction of each unit module can be completed using the obtained brightness and chromaticity correction coefficients of each pixel point; the brightness and chromaticity correction coefficients of each pixel point in each unit module can be downloaded to the unit module flash for brightness and chromaticity correction, or the unit modules whose brightness and chromaticity correction coefficients of each pixel point are obtained by the above method can be used to assemble and build an LED display screen, and then the brightness and chromaticity correction coefficients of each pixel point can be downloaded to the whole screen flash to complete the brightness and chromaticity correction of the entire LED display screen.

[0070] RXFixm k-q =Fix_RX*RXm k-q

[0071] RYFixm k-q =Fix_RY*RYm k-q

[0072] RZFix k-q =Fix_RZ*RZm k-q

[0073] GXFixm k-q =Fix_GX*GXm k-q

[0074] GYFixm k-q =Fix_GY*GYm k-q

[0075] GZFix k-q =Fix_GZ*GZm k-q

[0076] BXFixm k-q =Fix_BX*BXm k-q

[0077] BYFixm k-q =Fix_BY*BYm k-q

[0078] BZFixm k-q =Fix_BZ*BZm k-q

Claims

1. A method for calibrating a LED display unit module, characterized in that The method is as follows: Step 1: Build an LED display array with m*n box structures, 2≤m, n≤5; place the camera in front of the LED display array, collect the brightness and chromaticity of the entire array at one time, obtain the tristimulus value matrix of each pixel in the LED display array, and then calibrate the entire array to obtain a "quasi-flat" matrix for each pixel; Step 2: intercept the "quasi-flat" matrix of each pixel point of t display units in the center area of ​​the LED display array, t≤4; for any pixel point q in the i-th display unit, its "quasi-flat" matrix is ​​expressed as: RX i-q RY i-q , RZ i-q , GX i-q , GY i-q , GZ i-q , BX i-q 、BY i-q , BZ i-q , i = 1 ~ t; Step 3: Remove t display units in the center area of ​​the LED display array, and use the automated calibration equipment to collect brightness and chromaticity separately in turn to obtain the original three-stimulus value matrix of each pixel of each display unit; normalize the data obtained by the brightness and chromaticity collection of the entire array and the brightness and chromaticity collection of the display unit; for any pixel q in the i-th display unit, its normalized original three-stimulus value matrix is ​​expressed as: RX'm i-q RY'm i-q 、RZ'm i-q 、GX'm i-q , GY'm i-q 、GZ'm i-q 、BX'm i-q 、BY'm i-q 、BZ'm i-q , where i = 1 ~ t; Step 4: Use the "quasi-flattening" matrix of each pixel in the t display units in the center area and the normalized original three stimulus value matrix to obtain the lens vignetting correction matrix, which is expressed as: Fix_RX, Fix_RY, Fix_RZ, Fix_GX, Fix_GY, Fix_GZ, Fix_BX, Fix_BY, Fix_BZ; Fix_RX=(RX 1-q / RX’m 1-q +RX 2-q / RX’m 2-q +RX 3-q / RX’m 3-q +RX 4- q / RX’m 4-q ) / 4 Fix_RY=(RY 1-q / Rime 1-q +RY 2-q / Rime 2-q +RY 3-q / Rime 3-q +RY 4-q / Rime 4-q ) / 4 Fix_RZ=(RZ 1-q / RZ’m 1-q +RZ 2-q / RZ’m 2-q +RZ 3-q / RZ’m 3-q +RZ 4-q / RZ’m 4-q ) / 4 Fix_GX=(GX 1-q / GX’m 1-q +GX 2-q / GX’m 2-q +GX 3-q / GX’m 3-q +GX 4-q / GX’m 4-q ) / 4 Fix_GY=(GY 1-q / GY’m 1-q +GY 2-q / GY’m 2-q +GY 3-q / GY’m 3-q +GY 4-q / GY’m 4-q ) / 4 Fix_GZ=(GZ 1-q / GZ’m 1-q +GZ 2-q / GZ’m 2-q +GZ 3-q / GZ’m 3-q +GZ 4-q / GZ’m 4-q ) / 4 Fix_BX=(BX 1-q / BX’m 1-q +BX 2-q / BX’m 2-q +BX 3-q / BX’m 3-q +BX 4-q / BX’m 4-q ) / 4 Fix_BY=(BY 1-q / BY’m 1-q +BY 2-q / BY’m 2-q +BY 3-q / BY’m 3-q +BY 4-q / BY’m 4-q ) / 4 Fix_BZ=(BZ 1-q / BZ’m 1-q +BZ 2-q / BZ’m 2-q +BZ 3-q / BZ’m 3-q +BZ 4-q / BZ’m 4-q ) / 4 Step 5: Use automated calibration equipment to collect brightness and chromaticity of batch display units separately to obtain the original tristimulus value matrix of each pixel of each unit; For any pixel point, the original tristimulus value matrix of the pixel point is multiplied by the lens vignetting correction matrix to obtain its flat tristimulus value matrix, and its brightness and chromaticity correction coefficients are calculated using the flat tristimulus value matrix. The brightness and chromaticity correction coefficients of each pixel point are obtained to complete the brightness and chromaticity correction of each display unit.

2. The LED display unit module calibration method according to claim 1, characterized in that The display unit is a unit module.

3. The LED display unit module calibration method according to claim 1, characterized in that The display unit is a unit module of h×w, where h is the number of rows of modules in the unit module, and w is the number of columns of modules in the unit module, h=1-3, and w=1-2.

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