MLED display screen yin and yang face automatic correction method and system

Abstract

The invention relates to a method, a device and a system for automatically correcting positive and negative surfaces of an MLED display screen. The method comprises the following steps: S1, randomly dividing the MLED display screen into two areas; s2, controlling the MLED display screen to display a full-white image at a random brightness value, and respectively obtaining light signals of the two areas; converting the optical signal into an electric signal, and obtaining a first unit area electric signal and a second unit area electric signal according to the electric signal; s3, calculating the overlap ratio of the first unit area electric signal and the second unit area electric signal, and judging whether a yin-yang surface condition exists or not according to the overlap ratio; s4, if the conditions of the yin side and the yang side exist, the MLED lamp beads are corrected according to the coincidence degree; and S5, circulating the steps S1 to S4 until a preset number of cycles are continuously carried out, and the condition of negative and positive surfaces does not occur. By adopting the method, the lamp beads of the MLED display screen are automatically corrected, so that the manual operation is reduced, and the accuracy and efficiency of correcting the positive and negative surfaces of the MLED display screen are improved.

Description

Technical Field

[0001] The invention belongs to the technical field of display devices, and in particular relates to a method and system for automatically correcting positive and negative surfaces of an MLED display screen. Background Art

[0002] With the continuous development of science and technology, LED display screens have been widely used in various fields. However, the existing LED modules have many shortcomings in the correction of the positive and negative sides.

[0003] At present, the existing LED modules are mainly corrected for the positive and negative sides through the control of patch operations, such as steel screen printing and furnace temperature control. This correction method is time-consuming and labor-intensive, and it is difficult to accurately control the correction of the positive and negative sides. On the one hand, steel screen printing and furnace temperature control require a high degree of technical experience and delicate operation, and have high requirements for operators. On the other hand, even after careful operation, it is difficult to ensure accurate correction every time due to human factors and process limitations, which seriously restricts production efficiency.

[0004] The existence of the positive and negative side problem not only affects the visual effect of the LED display, reduces the quality of the product, but also brings pressure on the production enterprises to increase costs and reduce market competitiveness. Therefore, a more efficient and accurate automatic correction method for the positive and negative side of the MLED display is urgently needed to meet the market demand for high-quality LED displays. Summary of the invention

[0005] Based on this, it is necessary to provide a method, device and system for automatic correction of the positive and negative surfaces of an MLED display screen, which can improve the correction accuracy and efficiency of the positive and negative surfaces, in order to address the above technical problems.

[0006] In a first aspect, the present application provides a method for automatically correcting the positive and negative sides of an MLED display screen, comprising:

[0007] S1, randomly divide the MLED display screen into two areas;

[0008] S2. Control the MLED display screen to display a full white image with a random brightness value, and obtain light signals from the two areas respectively; convert the light signals into electrical signals, and obtain a first electrical signal per unit area and a second electrical signal per unit area according to the electrical signals; wherein the first electrical signal per unit area and the second electrical signal per unit area are used to characterize the luminous intensity per unit area of ​​the display screen in the two areas.

[0009] S3, calculating the overlap between the first unit area electrical signal and the second unit area electrical signal, and judging whether the MLED display screen has a positive and negative side according to the overlap;

[0010] S4. If there is a positive and negative side, calibrate the MLED lamp beads according to the overlap;

[0011] S5, cycle S1 to S4 until a preset number of cycles are performed continuously without any positive or negative side situation.

[0012] In a second aspect, the present application also provides an automatic correction device for positive and negative surfaces of an MLED display screen, comprising:

[0013] A region division module is used to randomly divide the MLED display screen into two regions;

[0014] The signal acquisition and processing module is used to control the MLED display screen to display a full white image with a random brightness value, and respectively acquire light signals of the two areas; convert the light signals into electrical signals, and obtain a first unit area electrical signal and a second unit area electrical signal according to the electrical signals; wherein the first unit area electrical signal and the second unit area electrical signal are used to characterize the luminous intensity per unit area of ​​the display screen in the two areas;

[0015] A judgment module, used to calculate the overlap between the first unit area electrical signal and the second unit area electrical signal, and judge whether the MLED display screen has a positive and negative side according to the overlap;

[0016] The correction module is used to correct the MLED lamp beads according to the overlap when there is a positive and negative surface situation;

[0017] The circulation module is used to control the above modules to perform cyclic operation until a preset number of cycles are continuously cycled and no positive or negative side appears on the MLED display screen.

[0018] In a third aspect, the present application also provides an automatic correction system for positive and negative surfaces of an MLED display screen, comprising: an MLED display screen, an optical receiver, a signal processor, a server and a controller;

[0019] The server is connected to the MLED display screen and is used to obtain the layout information of the pixels of the MLED display screen; the MLED display screen is randomly divided into two areas according to the layout information; the server is also used to control the display of the MLED display screen;

[0020] The optical receiver signal processor is connected to and installed above the MLED display screen; the optical receiver is used to receive optical signals when two areas of the MLED display screen display a full white image with random brightness values, convert the optical signals into electrical signals, and send the electrical signals to the signal processor;

[0021] The signal processor is connected to the server, and the signal processor processes the electrical signal to obtain a first electrical signal per unit area and a second electrical signal per unit area, and sends the first electrical signal per unit area and the second electrical signal per unit area to the server; wherein the first electrical signal per unit area and the second electrical signal per unit area are used to characterize the luminous intensity per unit area of ​​the display screens in the two regions;

[0022] The server is also connected to the controller, and is used to calculate the overlap between the first unit area electrical signal and the second unit area electrical signal, and determine whether the MLED display screen has a positive and negative surface according to the overlap; if there is a positive and negative surface, a correction instruction is generated according to the overlap and sent to the controller;

[0023] The controller calibrates the MLED lamp beads in response to the received calibration instruction;

[0024] The server is also connected to the optical receiver, and is also used to control the MLED display screen, optical receiver, signal processor and controller to operate in a loop to implement the method described in the first aspect, until a preset number of cycles are continuously cycled and no positive or negative side condition occurs on the MLED display screen.

[0025] The above-mentioned method, device and system for automatically correcting the positive and negative sides of the MLED display screen automatically correct the lamp beads of the MLED display screen, thereby reducing manual operations and improving the accuracy and efficiency of correcting the positive and negative sides of the MLED display screen. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the related technologies, the drawings required for use in the embodiments or the related technical descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0027] Figure 1 A schematic diagram of a flow chart of a method for automatically correcting the positive and negative surfaces of an MLED display screen provided by the present invention;

[0028] Figure 2 A schematic diagram of a flow chart of calibrating an MLED lamp bead in an optional embodiment of the present invention;

[0029] Figure 3 A schematic diagram of a flow chart of calculating the degree of brightness unevenness and confirming that lamp beads need to be corrected in an optional embodiment of the present invention;

[0030] Figure 4 A schematic diagram of a flow chart for formulating a correction strategy in an optional embodiment of the present invention;

[0031] Figure 5 A schematic structural diagram of a device for automatically correcting positive and negative surfaces of an MLED display screen provided by the present invention. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application 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 application and are not used to limit the present application.

[0033] refer to Figure 1 , which shows a flow chart of a method for automatically correcting the positive and negative surfaces of an MLED display screen provided in an embodiment of the present application, comprising the following steps:

[0034] S101, randomly dividing the MLED display screen into two areas.

[0035] Specifically, the MLED display screen can be randomly divided into two independent areas by generating random coordinates or using a specific algorithm. This step provides two different analysis objects for subsequent operations.

[0036] S102, controlling the MLED display screen to display a full white image with a random brightness value, and obtaining light signals from two areas respectively; converting the light signals into electrical signals, and obtaining a first electrical signal per unit area and a second electrical signal per unit area according to the electrical signals; wherein the first electrical signal per unit area and the second electrical signal per unit area are used to characterize the luminous intensity per unit area of ​​the display screen in the two areas.

[0037] Specifically, the MLED display screen is controlled to display a full white image and a random brightness value is set to simulate different usage scenarios. Then, the light signals of the two areas are obtained by connecting to the light sensor or other detection equipment of the display screen. Next, these light signals are converted into electrical signals, which can be achieved through a specific circuit or sensor module. According to the intensity of the electrical signal and the area of ​​the area, the unit area electrical signals of the two areas are calculated, which are recorded as the first unit area electrical signal and the second unit area electrical signal. These electrical signals reflect the luminous intensity per unit area of ​​the display screen in the two areas.

[0038] S103, calculating the overlap between the first unit area electrical signal and the second unit area electrical signal, and judging whether the MLED display screen has a positive and negative side according to the overlap.

[0039] Specifically, a specific algorithm is used to calculate the overlap of two unit area electrical signals. The overlap can be determined by comparing the values, trends or other characteristics of the electrical signals. If the overlap is low, it means that the luminous intensity of the two areas is very different, and there may be a positive and negative side problem. The preset threshold or judgment standard is used to determine whether the display screen has a positive and negative side problem.

[0040] S104. If there is a positive and negative side situation, calibrate the MLED lamp beads according to the overlap degree.

[0041] Specifically, if it is determined that the MLED display screen has a positive and negative side, the correction method will be determined based on the overlap information. This may involve adjusting the brightness, position, color or other parameters of the lamp beads to make the luminous intensity of the two areas closer. The program can achieve correction of the lamp beads by controlling the driving circuit of the display screen or using a specific correction algorithm.

[0042] S105, loop S101 to S104 until a preset number of cycles are performed continuously and no positive or negative side appears on the MLED display screen.

[0043] Specifically, the operations of S101 to S104 are continuously repeated until the preset number of cycles are continuously cycled and the MLED display screen has no positive and negative sides. In each cycle, the program will re-shorthand divide the display screen area, obtain light signals, calculate the overlap and perform correction. If the MLED display screen has no positive and negative sides in the preset number of cycles, the correction is considered successful and the cycle is stopped. Otherwise, the program will continue to cycle until the requirement is met.

[0044] By utilizing the above method, the lamp beads of the MLED display screen are automatically calibrated, thereby reducing manual operations and improving the accuracy and efficiency of calibrating the positive and negative sides of the MLED display screen.

[0045] In an optional embodiment, obtaining a first unit area electrical signal and a second unit area electrical signal according to the electrical signal includes the following steps:

[0046] Amplifying and filtering the electrical signal to obtain a first initial electrical signal V1(t) and a second initial electrical signal V2(t);

[0047] According to the number of pixels n1 and n2 corresponding to the two regions, calculate and The first unit area electrical signal and the second unit area electrical signal are denoted as V′1(t) and V′2(t).

[0048] Specifically, since the original electrical signal may be relatively weak or there is noise interference, the program will use an amplifier to amplify the electrical signal to enhance the signal strength for subsequent processing. At the same time, in order to remove noise and interference in the electrical signal, the program will use a filter to filter the electrical signal. After amplification and filtering, a relatively pure and appropriate strength first initial electrical signal V1(t) and a second initial electrical signal V2(t) are obtained, corresponding to the electrical signals of the two regions respectively.

[0049] The number of pixels n1 and n2 in each of the two areas of the MLED display screen can be determined by reading the parameters of the display screen or using a specific image analysis algorithm. Then, the intensity value of the first initial electrical signal V1(t) is divided by the number of pixels in the first area to obtain the first unit area electrical signal V′1(t), which represents the electrical signal value corresponding to the luminous intensity per unit area of ​​the display screen in the first area. Similarly, the intensity value of the second initial electrical signal V2(t) is divided by the number of pixels in the second area to obtain the second unit area electrical signal V′2(t). In this way, the program can convert the electrical signal into an indicator related to the luminous intensity per unit area of ​​the display screen, so as to facilitate the subsequent calculation of the degree of overlap and the judgment of the positive and negative sides.

[0050] In an optional embodiment, calculating the overlap between the first unit area electrical signal and the second unit area electrical signal, and judging whether the MLED display screen has a positive and negative side according to the overlap, comprises the following steps:

[0051] The correlation coefficient r of the first unit area electrical signal and the second unit area electrical signal is calculated using the following formula: in, and are the average values ​​of signals V′1(t) and V′2(t) in the same time interval, and the value range of r is [-1, 1];

[0052] The calculated r is compared with the preset threshold r th For comparison, if r <r th , it is determined that the MLED display screen has positive and negative sides.

[0053] Specifically, the overlap degree of the first unit area electrical signal and the second unit area electrical signal is calculated. First, the time interval [T1, T2] is determined. This time interval can be set according to specific application scenarios and requirements. In this time interval, the average values ​​of the first unit area electrical signal and the second unit area electrical signal are calculated respectively, and recorded as and The calculation formula is: and Then, for n time points t in the time interval [T1, T2], calculate , and add up these values. At the same time, calculate and Finally, according to the correlation coefficient calculation formula Calculate the correlation coefficient r. The value range of the correlation coefficient r is [-1, 1], which reflects the degree of linear correlation between the two signals.

[0054] Determine whether the MLED display screen has a yin-yang side situation based on the degree of overlap. A threshold is preset, which can be determined based on experience or experimental data, and is used to determine whether the MLED display screen has a yin-yang side situation. If the calculated correlation coefficient is less than the preset threshold, it means that the linear correlation between the first unit area electrical signal and the second unit area electrical signal is low, that is, the unit area luminous intensity of the two areas is different, and the program determines that the MLED display screen has a yin-yang side situation. If the correlation coefficient is greater than or equal to the preset threshold, it is considered that the unit area luminous intensity of the two areas is relatively close, and the MLED display screen does not have a yin-yang side situation.

[0055] refer to Figure 2 In an optional embodiment, if there is a positive and negative surface situation, the MLED lamp bead is calibrated according to the overlap, including the following steps:

[0056] S201, calculating the degree of brightness unevenness according to the overlap degree, and determining the lamp beads that need to be corrected according to the brightness value.

[0057] S202. Formulate a correction strategy based on the degree of brightness unevenness and the lamp beads that need to be corrected.

[0058] S203, calibrating the MLED lamp beads according to the calibration strategy.

[0059] Specifically, if it is determined that the MLED display screen has a positive and negative side, the degree of brightness unevenness is calculated using the previously calculated overlap (correlation coefficient). The degree of unevenness can be determined based on the difference between the overlap and the ideal overlap under completely uniform conditions. Next, the lamp beads that need to be corrected are determined by analyzing the brightness values ​​corresponding to each lamp bead. The lamp beads that need to be corrected can be determined by comparing the difference between the brightness values ​​of the lamp beads in different areas and the overall average brightness value, or by screening out the lamp beads with abnormal brightness through a specific algorithm.

[0060] The intensity and priority of correction can be determined according to the degree of brightness unevenness. If the unevenness is large, a more aggressive correction strategy may be required; if the unevenness is small, a more gentle adjustment method can be used. For the lamp beads that need to be corrected, a specific correction strategy can be formulated based on their position in the display, the brightness of the surrounding lamp beads, and the overall brightness distribution. For example, the brightness value, position parameters, color parameters of the lamp beads can be adjusted, or the correction can be achieved by adjusting the driving current.

[0061] Finally, according to the formulated correction strategy, the MLED lamp beads that need to be corrected are actually adjusted. This may involve communication with the display driver circuit, such as sending a specific control signal to change the working state of the lamp beads to achieve the purpose of correcting uneven brightness.

[0062] refer to Figure 3 In an optional embodiment, the degree of brightness unevenness is calculated according to the overlap degree, and the lamp beads that need to be corrected are determined according to the brightness value, including the following steps:

[0063] S301, according to and The size of the area to be corrected is determined by Then confirm The corresponding area is the area to be corrected; if Then confirm The corresponding area is the area that needs to be corrected;

[0064] S302, collect the brightness values ​​of N sampling points in the area, and express the coordinates of the sampling points as (x i ,y i ) and the corresponding brightness value is L ij ;

[0065] S303, using bilinear interpolation to calculate the brightness value L(x, y) of any point (x, y) in the region, including:

[0066] According to the points (x, y) to be calculated, four sampling points (x i ,y i )、(x i+1 ,y i )、(x i ,y i+1 ) and (x i+1 ,y i+1 ); where the point (x, y) is located at the sampling point (x i ,y i )、(x i+1 ,y i )、(x i ,y i+1 ) and (x i+1 ,y i+1 )between;

[0067] Calculate the interpolation coefficients in the horizontal direction and the interpolation coefficients in the vertical direction

[0068] The brightness value of the point (x, y) is calculated using the bilinear interpolation formula. The calculation formula is:

[0069] L(x,y)=(1-a)(1-b)L ij +a(1-b)L i+1，j +(1-a)bL i,j+1 +abL i+1,j+1 ;

[0070] Draw brightness value contour lines according to points with the same brightness value; if there is a portion where the spacing between two adjacent brightness value contour lines is less than a preset contour line spacing threshold, determine the MLED lamp beads in the area between the two adjacent contour lines and where the spacing is less than the preset contour line spacing threshold as lamp beads that need to be calibrated;

[0071] S304: Calculate the correlation coefficient r and the preset threshold r th The difference Δr is used to represent the degree of brightness unevenness.

[0072] Specifically, we first need to determine the area where the lamp beads that need to be calibrated are located. Compare the average values ​​of signals V′1(t) and V′2(t) in the same time interval ( and ) size. When The corresponding area is determined as the area that needs to be corrected; when When The corresponding area is determined as the area that needs to be corrected. Because in the actual operation, The probability is very small, so it can be ignored.

[0073] After determining the area to be corrected, first collect brightness data for this area, and select a series of sampling points on the LED display to obtain brightness data. For example, the resolution of the LED display is M×N (M is the number of horizontal pixels, N is the number of vertical pixels). In order to accurately depict the brightness distribution, a uniform sampling strategy can be adopted. For example, select a sampling point every k pixels in the horizontal direction, and select a sampling point every l pixels in the vertical direction. The coordinates of the horizontal sampling points are The coordinates of the vertical sampling points are Use L ij Indicates that at the coordinate (x i ,y i ) can be determined by the brightness detection module in combination with the position information of the light collector and the converted electrical signal. For example, after the light collector converts the light signal into an electrical signal, it is amplified, filtered, and processed by the signal processing module, and then the electrical signal strength is converted into a brightness value through a pre-calibrated conversion formula. Assume that the electrical signal strength is V ij , the conversion formula can be L ij =α×V ij +β, where α and β are coefficients obtained by calibration against a standard light source of known brightness.

[0074] After collecting the brightness values ​​of discrete sampling points, in order to obtain the brightness value of any point on the entire display screen, an interpolation algorithm is needed. Bilinear interpolation is a commonly used method. For any point (x, y) on the display screen, assume that it is located at four sampling points (x i ,y i )、(x i+1 ,y i )、(x i ,y i+1 ) and (x i+1 ,y i+1 ). First, calculate the interpolation coefficient in the horizontal direction and the interpolation coefficients in the vertical direction Then, the brightness value of the point (x, y) is calculated by the bilinear interpolation formula, and the calculation formula can be L(x, y) = (1-a)(1-b)L ij +a(1-b)L i+1，j +(1-a)bL i，j+1 +abL i+1，j+1 ; In this way, the brightness distribution on the entire display screen can be obtained.

[0075] Draw brightness contours based on the brightness distribution. Suppose we set a series of brightness contour values ​​C k (k=1,2,…,n), for each C k , we need to find the screen that satisfies L(x, y) = C k This can be an iterative process. Starting from a corner of the display screen, traverse the points on the display screen in a certain scanning order (for example, from left to right, from top to bottom). When a point (x, y) with a brightness value L(x, y) between C k and C k+1 When the contour line is between , linear interpolation is needed to determine the intersection of the contour line and the line segment around the point. For example, suppose the brightness values ​​of two adjacent points (x, y) and (x+Δx, y) in the horizontal direction are L(x, y) and L(x+Δx, y) respectively. If C k Between these two brightness values, the abscissa x′ of the intersection of the contour line and the line segment [(x, y), (x+Δx, y)] can be calculated by linear interpolation, and the calculation formula is: In this way, each brightness contour can be plotted.

[0076] Determine the lamp beads that need to be adjusted based on the contour spacing. The contour spacing refers to the distance between two adjacent contour lines. For brightness contour lines, the spacing can be measured by the brightness difference ΔL corresponding to two adjacent contour lines. For example, the brightness corresponding to two adjacent contour lines is L1 and L2, then ΔL=|L1-L2|. Set a contour spacing threshold ΔL th , when ΔL is less than ΔL th When the distance between the two contour lines is smaller, it can be determined that the LED lamp beads in this area (the area between the two contour lines) need to be adjusted. This is because the smaller the contour line spacing, the more drastic the brightness change in this area is, which is likely to be a manifestation of the yin-yang side phenomenon.

[0077] Calculate the correlation coefficient r and the preset threshold r th The difference Δr is used to characterize the degree of brightness unevenness. The larger the Δr, the higher the brightness unevenness, and the more intense the correction operation is required. This difference can be used as a quantitative indicator to help determine the intensity and priority of the correction.

[0078] refer to Figure 4 In an optional embodiment, a correction strategy is formulated according to the degree of brightness unevenness and the lamp beads that need to be corrected, including the following steps:

[0079] S401. For each lamp bead that needs to be corrected, based on the pre-established mapping relationship between the brightness unevenness degree Δr and the brightness adjustment ratio and the position fine-tuning amount, the brightness adjustment ratio k and the position fine-tuning amount corresponding to each lamp bead that needs to be corrected are obtained according to the brightness unevenness degree Δr; the position fine-tuning amount includes the horizontal fine-tuning amount Δx and the vertical fine-tuning amount Δy.

[0080] S402, taking each lamp bead to be calibrated and the corresponding brightness adjustment ratio k and position fine-tuning amount as a calibration strategy.

[0081] Specifically, a mapping relationship is first pre-established, which associates the brightness unevenness with the brightness adjustment ratio and the position fine-tuning amount. The brightness unevenness is a quantitative value that reflects the size of the brightness difference between different areas in the display screen.

[0082] For each lamp bead that needs to be corrected, the program will find the corresponding brightness adjustment ratio k and position fine-tuning amount in the mapping relationship according to the degree of brightness unevenness in the area where it is located. The brightness adjustment ratio k determines the amplitude by which the brightness of the lamp bead needs to be adjusted. For example, if k is 1.2, it means that the brightness of the lamp bead needs to be increased by 20%; if k is 0.8, it means that the brightness of the lamp bead needs to be reduced by 20%. The position fine-tuning amount includes the horizontal fine-tuning amount Δx and the vertical fine-tuning amount Δy, which are used to fine-tune the position of the lamp bead to improve the uniformity of the brightness distribution. The horizontal fine-tuning amount Δx and the vertical fine-tuning amount Δy can be pixel-level adjustments, such as moving a few pixels to the left or right, or a few pixels up or down.

[0083] Each lamp bead that needs to be corrected and the corresponding brightness adjustment ratio k and position fine-tuning amount are combined to form a correction strategy. This correction strategy can be used to guide the actual correction operation of the MLED lamp bead. For example, an instruction can be generated according to this correction strategy, and this instruction is sent to the drive circuit. The drive circuit responds to this instruction and performs corresponding correction operations on the lamp bead that needs to be corrected.

[0084] In an optional embodiment, the MLED lamp beads are calibrated according to the calibration strategy, including the following steps:

[0085] Correct the input current I1 of the lamp bead to be corrected to I2, I2 = (1 + k) I1;

[0086] According to the horizontal fine-tuning amount Δx and the vertical fine-tuning amount Δy, the position of the lamp bead to be corrected is moved.

[0087] Specifically, first determine the lamp beads that need to be corrected. For each lamp bead that needs to be corrected, the program obtains its current input current size I1. According to the brightness adjustment ratio k determined in the correction strategy, calculate the corrected current size I2. The formula I2 = (1 + k) I1 means that if k is a positive number, the corrected current will be larger than the original current, thereby increasing the brightness of the lamp bead; if k is a negative number, the corrected current will be smaller than the original current, thereby reducing the brightness of the lamp bead. The program adjusts the brightness of the lamp bead by adjusting the input current size of the lamp bead to improve the uneven brightness.

[0088] According to the horizontal fine-tuning amount Δx and vertical fine-tuning amount Δy determined in the calibration strategy, the position of the light beads to be calibrated is moved. If the horizontal fine-tuning amount Δx is positive, the program moves the light beads to the right by the corresponding number of pixels in the horizontal direction; if the horizontal fine-tuning amount Δx is negative, the program moves the light beads to the left by the corresponding number of pixels in the horizontal direction. Similarly, for the vertical fine-tuning amount Δy, if it is positive, the light beads are moved downward by the corresponding number of pixels in the vertical direction; if it is negative, the light beads are moved upward by the corresponding number of pixels in the vertical direction. By fine-tuning the position of the light beads, the brightness uniformity of the display screen can be further improved.

[0089] In an alternative embodiment, randomly dividing the MLED display screen into two regions includes the following steps:

[0090] Assign a random value X to each pixel point ij ; where X ij is a random number uniformly distributed in the interval [0, 1];

[0091] Randomly set the division threshold T, where 0 < T < 1;

[0092] For each pixel point, if X ij < T, the pixel point is divided into region A; if X ij ≥ T, the pixel point is divided into region B.

[0093] Specifically, first, for each pixel point on the MLED display screen, generate a random number X uniformly distributed in the interval [0, 1] ij . This can be achieved by calling a random number generation function to ensure that each pixel point is assigned an independent random value.

[0094] Randomly select a value in the interval (0, 1) as the division threshold T. This threshold will determine which region the pixel point is divided into. Since T is randomly generated, the division method of the two regions will be different each time the division operation is performed, thus achieving random division.

[0095] For each pixel point on the display screen, compare its random value X ij with the division threshold T. If X ij < T, it means that the random value of this pixel point is less than the threshold, and the program divides this pixel point into region A. If X ij ≥ T, that is, the random value of the pixel point is greater than or equal to the threshold, the pixel point is divided into region B. In this way, all pixel points on the display screen are randomly divided into two regions.

[0096] In an alternative embodiment, the method further includes the step of: displaying the current state of the light beads and the calibration result.

[0097] Specifically, after the lamp beads are calibrated, the brightness value changes before and after the calibration can be compared. The brightness change trend of the two areas before and after the calibration can be displayed in the form of a chart, or the increase or decrease in the brightness value can be directly displayed. For the lamp beads that need to be calibrated, the brightness value after calibration is highlighted, and the brightness comparison with the surrounding lamp beads is used to verify whether the calibration effect meets expectations.

[0098] If the position of the lamp beads is fine-tuned, the change in the position of the lamp beads can be displayed in a graphical way. For example, on the simulated image of the display screen, different colors or marks are used to indicate the position of the lamp beads before and after correction, so that users can intuitively see the effect of position fine-tuning. After the position is fine-tuned, the layout relationship between the lamp beads and the surrounding lamp beads is more reasonable, and the impact on brightness uniformity.

[0099] By displaying the current status of the lamp beads and the correction results, users can understand the status and correction progress of the MLED display in real time, which facilitates timely adjustment of the correction strategy and improves the accuracy and efficiency of the correction.

[0100] It should be understood that, although the various steps in the flowcharts involved in the above-mentioned embodiments are displayed in sequence according to the indication of the arrows, these steps are not necessarily executed in sequence according to the order indicated by the arrows. Unless there is a clear explanation in this article, the execution of these steps does not have a strict order restriction, and these steps can be executed in other orders. Moreover, at least a part of the steps in the flowcharts involved in the above-mentioned embodiments can include multiple steps or multiple stages, and these steps or stages are not necessarily executed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily to be carried out in sequence, but can be executed in turn or alternately with other steps or at least a part of the steps or stages in other steps.

[0101] Based on the same inventive concept, the embodiment of the present application also provides an MLED display screen positive and negative surface automatic correction device for implementing the above-mentioned MLED display screen positive and negative surface automatic correction method. The implementation scheme for solving the problem provided by the device is similar to the implementation scheme recorded in the above-mentioned method, so the specific limitations in one or more embodiments of the MLED display screen positive and negative surface automatic correction device provided below can refer to the limitations of the MLED display screen positive and negative surface automatic correction method above, and will not be repeated here.

[0102] In an exemplary embodiment, Figure 3 As shown, a device 400 for automatically correcting the positive and negative sides of an MLED display screen is provided, and the device comprises:

[0103] The area division module 401 is used to randomly divide the MLED display screen into two areas.

[0104] The signal acquisition and processing module 402 is used to control the MLED display screen to display a full white image with a random brightness value, and respectively acquire the light signals of the two areas; convert the light signals into electrical signals, and obtain a first unit area electrical signal and a second unit area electrical signal according to the electrical signals; wherein the first unit area electrical signal and the second unit area electrical signal are used to characterize the luminous intensity per unit area of ​​the display screen of the two areas.

[0105] The judgment module 403 is used to calculate the overlap between the first electrical signal per unit area and the second electrical signal per unit area, and judge whether the MLED display screen has a positive and negative side according to the overlap.

[0106] The correction module 404 is used to correct the MLED lamp beads according to the overlap when the positive and negative surfaces exist.

[0107] The circulation module 405 is used to control the above modules to perform circulation operation until a preset number of cycles are continuously cycled and no positive or negative side situation occurs on the MLED display screen.

[0108] Optionally, the signal acquisition and processing module 402 includes:

[0109] The electrical signal preprocessing unit is used to amplify and filter the electrical signal to obtain a first initial electrical signal V1(t) and a second initial electrical signal V2(t).

[0110] The unit area electrical signal calculation unit is used to calculate the number of pixels n1 and n2 corresponding to the two areas. and The first unit area electrical signal and the second unit area electrical signal are denoted as V′1(t) and V′2(t).

[0111] Optionally, the determination module 403 includes:

[0112] The correlation coefficient calculation unit is used to calculate the correlation coefficient r of the first unit area electrical signal and the second unit area electrical signal, and the calculation formula is: in, and are the average values ​​of signals V′1(t) and V′2(t) in the same time interval, and the value range of r is [-1, 1].

[0113] The positive and negative side judgment unit is used to compare the calculated r with the preset threshold r th For comparison, if r <r th, it is determined that the MLED display screen has positive and negative sides.

[0114] Optionally, the correction module 404 includes:

[0115] The unit for calculating the degree of brightness unevenness and determining the lamp beads that need to be corrected is used to calculate the degree of brightness unevenness according to the overlap degree and determine the lamp beads that need to be corrected according to the brightness value.

[0116] The correction strategy formulation unit is used to formulate a correction strategy according to the degree of brightness unevenness and the lamp beads that need to be corrected.

[0117] The execution unit is used to calibrate the MLED lamp beads according to the calibration strategy.

[0118] Optionally, the unit for calculating the uneven brightness and determining the lamp beads that need to be corrected is specifically used to perform the following operations, including:

[0119] Step 1: According to and The size of the area to be corrected is determined; if Then confirm The corresponding area is the area that needs to be corrected.

[0120] Step 2: Collect the brightness values ​​of N sampling points in the area, and express the coordinates of the sampling points as (x i ,y i ) and the corresponding brightness value is L ij .

[0121] Step 3: Use bilinear interpolation to calculate the brightness value L(x, y) of any point (x, y) in the area, including:

[0122] According to the points (x, y) to be calculated, four sampling points (x i ,y i )、(x i+1 ,y i )、(x i ,y i+1 ) and (x i+1 ,y i+1 ); where the point (x, y) is located at the sampling point (x i ,y i )、(x i+1 ,y i )、(x i ,y i+1 ) and (x i+1 ,y i+1 )between;

[0123] Calculate the interpolation coefficients in the horizontal direction and the interpolation coefficients in the vertical direction

[0124] The brightness value of the point (x, y) is calculated using the bilinear interpolation formula. The calculation formula is:

[0125] L(x,y)=(1-a)(1-b)L ij +a(1-b)L i+1，j +(1-a)bL i，j+1 +abL i+1，j+1 ;

[0126] Draw brightness value contour lines based on points with the same brightness value; if there is a part between two adjacent brightness value contour lines with a spacing less than a preset contour line spacing threshold, the MLED lamp beads located in the area between the two adjacent contour lines and with a spacing less than the preset contour line spacing threshold are determined as lamp beads that need to be calibrated.

[0127] Step 4: Calculate the correlation coefficient r and the preset threshold r th The difference Δr is used to represent the degree of brightness unevenness.

[0128] Optionally, the correction strategy formulation unit is specifically used to perform the following operations, including:

[0129] For each lamp bead to be corrected, based on the pre-established mapping relationship between the brightness unevenness Δr and the brightness adjustment ratio and position fine-tuning amount, the brightness adjustment ratio k and position fine-tuning amount corresponding to each lamp bead to be corrected are obtained according to the brightness unevenness Δr; the position fine-tuning amount includes the horizontal fine-tuning amount Δx and the vertical fine-tuning amount Δy;

[0130] Each lamp bead that needs to be corrected and its corresponding brightness adjustment ratio k and position fine-tuning amount are used as a correction strategy.

[0131] Optionally, the correction module 404 is specifically configured to perform the following operations, including:

[0132] Correct the input current I1 of the lamp bead to be corrected to I2, I2 = (1 + k) I1;

[0133] According to the horizontal fine-tuning amount Δx and the vertical fine-tuning amount Δy, the position of the lamp bead to be corrected is moved.

[0134] Optionally, the device also includes a display module for displaying the current status of the lamp beads and the calibration results.

[0135] The embodiment of the present application also provides an automatic correction system for the positive and negative sides of an MLED display screen, the system comprising: an MLED display screen, an optical receiver, a signal processor, a server and a controller;

[0136] The server is connected to the MLED display screen and is used to obtain the layout information of the pixels of the MLED display screen; the MLED display screen is randomly divided into two areas according to the layout information; the server is also used to control the display of the MLED display screen;

[0137] The optical receiver signal processor is connected to and installed above the MLED display screen; the optical receiver is used to receive optical signals when two areas of the MLED display screen display a full white image with random brightness values, convert the optical signals into electrical signals, and send the electrical signals to the signal processor;

[0138] The signal processor is connected to the server, and the signal processor processes the electrical signal to obtain a first electrical signal per unit area and a second electrical signal per unit area, and sends the first electrical signal per unit area and the second electrical signal per unit area to the server; wherein the first electrical signal per unit area and the second electrical signal per unit area are used to characterize the luminous intensity per unit area of ​​the display screens in the two regions;

[0139] The server is also connected to the controller, and is used to calculate the overlap between the first unit area electrical signal and the second unit area electrical signal, and determine whether the MLED display screen has a positive and negative surface according to the overlap; if there is a positive and negative surface, a correction instruction is generated according to the overlap and sent to the controller;

[0140] The controller calibrates the MLED lamp beads in response to the received calibration instruction;

[0141] The server is also connected to the optical receiver, and is also used to control the MLED display screen, optical receiver, signal processor and controller to operate in a loop to implement any of the above methods, until a preset number of cycles are continuously cycled and no positive or negative side appears on the MLED display screen.

[0142] Specifically, the MLED display screen can be a large screen composed of multiple MLED modules, each module containing thousands of micro LED lamp beads; the light receiver can be a photoelectric sensor such as a photodiode, a phototransistor or a photomultiplier tube; the signal processor can be a dedicated electronic circuit board containing an analog signal processing circuit and an analog-to-digital converter (ADC); the server can be a high-performance computer or industrial control computer (IPC) with sufficient computing power and storage capacity, as well as multiple communication interfaces; the controller can be an FPGA (field programmable gate array), a CPLD (complex programmable logic device) or other programmable logic controller.

[0143] The above devices can be connected using various types of cables or connectors, such as Ethernet cables, fiber optic cables, HDMI cables, etc., depending on the required data transmission rate and distance. The above devices can also be connected to each other wirelessly.

[0144] For the device embodiments, since they basically correspond to the method embodiments, the relevant parts can refer to the partial description of the method embodiments. The device embodiments described above are only schematic, wherein the components described as separate parts may or may not be physically separated, and the parts displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the disclosed solution. A person of ordinary skill in the art can understand and implement it without paying any creative work.

[0145] The above-mentioned embodiments only express several implementation methods of the embodiments of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the patent of the embodiments of the present application. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the embodiments of the present application, and these all belong to the protection scope of the embodiments of the present application.

Claims

1. A method for automatically correcting the positive and negative surfaces of an MLED display screen, characterized in that: The method comprises: S1, randomly divide the MLED display screen into two areas; S2. Control the MLED display screen to display a full white image with a random brightness value, and obtain light signals from the two areas respectively; convert the light signals into electrical signals, and obtain a first electrical signal per unit area and a second electrical signal per unit area according to the electrical signals; wherein the first electrical signal per unit area and the second electrical signal per unit area are used to characterize the luminous intensity per unit area of ​​the display screen in the two areas. S3, calculating the overlap degree of the first unit area electrical signal and the second unit area electrical signal, and judging whether the MLED display screen has the positive and negative side situation according to the overlap degree; S4. If the positive and negative surfaces exist, calibrate the MLED lamp beads according to the overlap degree; S5, cycle S1 to S4 until a preset number of cycles are performed continuously without any positive or negative side situation.

2. The method according to claim 1, characterized in that Obtaining a first unit area electrical signal and a second unit area electrical signal according to the electrical signal, comprising: Amplifying and filtering the electrical signal to obtain a first initial electrical signal V1(t) and a second initial electrical signal V2(t); According to the number of pixels n1 and n2 corresponding to the two regions, calculate and The first electrical signal per unit area and the second electrical signal per unit area are denoted as V′1(t) and V′2(t).

3. The method according to claim 2, characterized in that The calculating the overlap between the first electrical signal per unit area and the second electrical signal per unit area, and judging whether the MLED display screen has a positive and negative side according to the overlap, comprises: The correlation coefficient r of the first unit area electrical signal and the second unit area electrical signal is calculated using the following formula: in, and are the average values ​​of signals V′1(t) and V′2(t) in the same time interval, and the value range of r is [-1,1]; The calculated r is compared with the preset threshold r th For comparison, if r <r th , it is determined that the MLED display screen has a positive and negative side.

4. The method according to claim 3, characterized in that If the positive and negative surfaces exist, the MLED lamp bead is calibrated according to the overlap, including: Calculate the degree of brightness unevenness according to the overlap, and determine the lamp beads that need to be corrected according to the brightness value; Formulate a correction strategy based on the uneven brightness and the lamp beads that need to be corrected; The MLED lamp beads are calibrated according to the calibration strategy.

5. The method according to any one of claim 4, characterized in that: The step of calculating the brightness unevenness according to the overlap degree and determining the lamp beads to be corrected according to the brightness value includes: Step 1: According to and The size of the area to be corrected is determined by Then confirm The corresponding area is the area to be corrected; if Then confirm The corresponding area is the area to be corrected; Step 2: Collect the brightness values ​​of N sampling points on the area, and express the coordinates of the sampling points as (x i ,y i ) and the corresponding brightness value is L ij ; Step 3: Use bilinear interpolation to calculate the brightness value L(x,y) of any point (x,y) in the area, including: According to the point (x, y) to be calculated, four sampling points (x i ,y i )、(x i+1 ,y i )、(x i ,y i+1 ) and (x i+1 ,y i+1 ); wherein the point (x, y) is located at the sampling point (x i ,y i )、(x i+1 ,y i )、(x i ,y i+1 ) and (x i+1 ,y i+1 )between; Calculate the interpolation coefficients in the horizontal direction and the interpolation coefficients in the vertical direction The brightness value of the point (x, y) is calculated using the bilinear interpolation formula. The calculation formula is: L(x,y)=(1-a)(1-b)L ij +a(1-b)L i+1,j +(1-A)bL i,j+1 +abL i+1,j+1 ; Draw brightness value contour lines according to points with the same brightness value; if there is a portion where the spacing between two adjacent brightness value contour lines is less than a preset contour line spacing threshold, determine the MLED lamp beads in the area between the two adjacent contour lines and where the spacing is less than the preset contour line spacing threshold as lamp beads that need to be calibrated; Step 4: Calculate the correlation coefficient r and the preset threshold r th The difference Δr is used to represent the degree of brightness unevenness.

6. The method according to claim 5, characterized in that The method of formulating a correction strategy according to the uneven brightness and the lamp beads to be corrected includes: For each of the lamp beads to be corrected, based on the pre-established mapping relationship between the brightness unevenness degree Δr and the brightness adjustment ratio and the position fine-tuning amount, the brightness adjustment ratio k and the position fine-tuning amount corresponding to each of the lamp beads to be corrected are obtained according to the brightness unevenness degree ΔR; the position fine-tuning amount includes a horizontal fine-tuning amount Δx and a vertical fine-tuning amount Δy; Each of the lamp beads to be corrected and the corresponding brightness adjustment ratio k and the position fine-tuning amount are used as the correction strategy.

7. The method according to claim 6, characterized in that The step of calibrating the MLED lamp beads according to the calibration strategy includes: Correct the input current I1 of the lamp bead to be corrected to I2, where I2=(1+k)I1; The position of the lamp bead to be corrected is moved according to the horizontal fine adjustment amount ΔX and the vertical fine adjustment amount Δy.

8. The method according to claim 1, characterized in that The MLED display screen is randomly divided into two areas, including: Assign a random value X to each pixel ij ; Among them, X ij is a random number uniformly distributed in the interval [0,1]; Randomly set the partition threshold T, where 0 <T<1; For each of the pixel points, if X ij < T, then divide the pixel point into region A; if X ij ≥ T, then divide the pixel point into region B.

9. An automatic correction device for positive and negative surfaces of an MLED display screen, characterized in that: The device comprises: A region division module is used to randomly divide the MLED display screen into two regions; A signal acquisition and processing module, used to control the MLED display screen to display a full white image with a random brightness value, and respectively acquire light signals of the two regions; convert the light signals into electrical signals, and obtain a first unit area electrical signal and a second unit area electrical signal according to the electrical signals; wherein the first unit area electrical signal and the second unit area electrical signal are used to characterize the luminous intensity per unit area of ​​the display screen of the two regions; A judgment module, used for calculating the overlap between the first electrical signal per unit area and the second electrical signal per unit area, and judging whether the MLED display screen has a positive and negative side according to the overlap; A correction module, used for correcting the MLED lamp beads according to the overlap when the positive and negative surfaces exist; The circulation module is used to control the above modules to perform cyclic operation until a preset number of cycles are continuously cycled and no positive or negative side appears on the MLED display screen.

10. An automatic correction system for positive and negative surfaces of an MLED display screen, characterized in that: The system includes: an MLED display screen, an optical receiver, a signal processor, a server and a controller; The server is connected to the MLED display screen and is used to obtain the layout information of the pixels of the MLED display screen; according to the layout information, the MLED display screen is randomly divided into two areas; the server is also used to control the display of the MLED display screen; The optical receiver and the signal processor are connected and installed above the MLED display screen; the optical receiver is used to receive the optical signal when the two areas of the MLED display screen display a full white image with random brightness values, convert the optical signal into an electrical signal, and send the electrical signal to the signal processor; The signal processor is connected to the server, and the signal processor processes the electrical signal to obtain a first electrical signal per unit area and a second electrical signal per unit area, and sends the first electrical signal per unit area and the second electrical signal per unit area to the server; wherein the first electrical signal per unit area and the second electrical signal per unit area are used to characterize the luminous intensity per unit area of ​​the display screens in the two regions; The server is also connected to the controller, and is used to calculate the overlap between the first unit area electrical signal and the second unit area electrical signal, and determine whether the MLED display screen has a positive and negative surface according to the overlap; if there is a positive and negative surface, a correction instruction is generated according to the overlap and the correction instruction is sent to the controller; The controller calibrates the MLED lamp beads in response to the received calibration instruction; The server is also connected to the optical receiver, and is also used to control the MLED display screen, optical receiver, signal processor and controller to operate in a loop to implement the method described in any one of claims 1-8, until a preset number of cycles are continuously cycled and no positive or negative side condition occurs on the MLED display screen.

Images