MLED display screen positive and negative surface automatic correction method and system

Abstract

The application relates to an MLED display screen positive and negative surface automatic correction method, device and system. The method comprises the following steps: S1, randomly dividing an MLED display screen into two regions; S2, controlling the MLED display screen to display a full white image with a random brightness value, and acquiring light signals of the two regions respectively; converting the light signals into electric signals, and obtaining a first unit area electric signal and a second unit area electric signal according to the electric signals; S3, calculating the coincidence degree of the first unit area electric signal and the second unit area electric signal, and judging whether there is a positive and negative surface condition according to the coincidence degree; S4, if there is a positive and negative surface condition, correcting MLED lamp beads according to the coincidence degree; and S5, circulating S1 to S4 until a preset circulation number is continuously circulated, and no positive and negative surface condition occurs. By adopting the method, the lamp beads of the MLED display screen are automatically corrected, manual operation is reduced, and the accuracy and efficiency of correcting the positive and negative surface of the MLED display screen are improved.

Description

Technical Field

[0001] This invention belongs to the field of display device technology, and in particular relates to an automatic correction method and system for the dark and light surfaces of an MLED display screen. Background Technology

[0002] With the continuous development of technology, LED displays have been widely used in various fields. However, existing LED modules have many shortcomings in terms of the correction of uneven lighting.

[0003] Currently, the calibration of the positive and negative sides of existing LED modules mainly relies on the control of the surface mount process, such as stencil printing and oven temperature control. This calibration method is time-consuming and labor-intensive, and it is difficult to accurately control the calibration of the positive and negative sides. On the one hand, stencil printing and oven temperature control require a high level of technical experience and meticulous operation, placing high demands on the operators. On the other hand, even with careful operation, due to human factors and process limitations, it is difficult to guarantee accurate calibration every time, which seriously restricts production efficiency.

[0004] The issue of uneven lighting on LED displays not only affects the visual effect and reduces product quality, but also puts pressure on manufacturers by increasing costs and reducing their market competitiveness. Therefore, there is an urgent need for a more efficient and accurate automatic uneven lighting correction method for MLED displays to meet the market demand for high-quality LED displays. Summary of the Invention

[0005] Therefore, it is necessary to provide an automatic correction method, device, and system for the yin-yang sides of an MLED display screen that can improve the accuracy and efficiency of yin-yang side correction, addressing the aforementioned technical problems.

[0006] In a first aspect, this application provides an automatic correction method for the uneven surface of an MLED display screen, including:

[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 random brightness values, and acquire the light signals of the two areas respectively; convert the light signals into electrical signals, and obtain the first unit area electrical signal and the second unit area electrical signal based on 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.

[0009] S3. Calculate the overlap of the first unit area electrical signal and the second unit area electrical signal, and determine whether the MLED display screen has a sun-and-shadow situation based on the overlap.

[0010] S4. If there is a situation of uneven surface, the MLED beads should be calibrated according to the degree of overlap;

[0011] S5, repeat S1 to S4 until the preset number of cycles has been completed, and no yin-yang situation occurs.

[0012] Secondly, this application also provides an automatic correction device for the uneven surface of an MLED display screen, comprising:

[0013] The area division module is used to randomly divide the MLED display screen into two areas;

[0014] The signal acquisition and processing module is used to control the MLED display screen to display a full white image with random brightness values, and to acquire light signals from two regions respectively; convert the light signals into electrical signals, and obtain a first unit area electrical signal and a second unit area electrical signal based on 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 regions.

[0015] The judgment module is used to calculate the overlap of the first unit area electrical signal and the second unit area electrical signal, and to determine whether the MLED display screen has a sun-and-shadow situation based on the overlap.

[0016] The calibration module is used to calibrate the MLED beads based on the degree of overlap when there are yin and yang sides.

[0017] The loop module controls the above modules to run in a loop until the preset number of loops has been completed, and the MLED display screen does not show any unevenness.

[0018] Thirdly, this application also provides an automatic correction system for the light and dark sides of an MLED display screen, including: an MLED display screen, a light receiver, a signal processor, a server, and a controller;

[0019] The server connects to the MLED display to obtain the pixel layout information of the MLED display; based on the layout information, it randomly divides the MLED display into two areas; the server is also used to control the display of the MLED screen.

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

[0021] The signal processor is connected to the server. The signal processor processes the electrical signal to obtain a first unit area electrical signal and a second unit area electrical signal, and sends the first unit area electrical signal and the second unit area electrical signal to the server. 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 regions.

[0022] The server is also connected to the controller to calculate the overlap of the first unit area electrical signal and the second unit area electrical signal, and to determine whether the MLED display screen has a yin-yang surface condition based on the overlap. If a yin-yang surface condition exists, a correction command is generated based on the overlap and sent to the controller.

[0023] The controller responds to the received calibration command and calibrates the MLED beads;

[0024] The server is also connected to the light receiver and is used to control the MLED display, light receiver, signal processor and controller to operate in a loop to achieve the method described in the first aspect, until the preset number of loops has been continuously completed without any unevenness on the MLED display.

[0025] The aforementioned method, device, and system for automatic correction of the uneven surface of an MLED display screen automatically corrects the LED beads of the MLED display screen, thereby reducing manual operation and improving the accuracy and efficiency of correcting the uneven surface of the MLED display screen. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments or related technologies of this application, the accompanying drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the accompanying 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 This is a flowchart illustrating an automatic correction method for the uneven surface of an MLED display screen provided by the present invention.

[0028] Figure 2 This is a schematic diagram of the process for calibrating MLED chips in an optional embodiment of the present invention;

[0029] Figure 3 This is a schematic diagram of the process for calculating the degree of brightness non-uniformity and identifying the LED beads that need to be calibrated in an optional embodiment of the present invention;

[0030] Figure 4 This is a flowchart illustrating the process of developing a correction strategy in one optional embodiment of the present invention;

[0031] Figure 5 This is a schematic diagram of the structure of an automatic correction device for the yin-yang surfaces of an MLED display screen provided by the present invention. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0033] refer to Figure 1 The document presents a flowchart illustrating an automatic correction method for the shadow and light areas of an MLED display screen, as provided in an embodiment of this application, comprising the following steps:

[0034] S101. Randomly divide 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. Control the MLED display screen to display a full white image with random brightness values, and acquire the light signals of the two regions respectively; convert the light signals into electrical signals, and obtain the first unit area electrical signal and the second unit area electrical signal based on 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 regions.

[0037] Specifically, the MLED display screen is controlled to display a pure white image, and a random brightness value is set to simulate different usage scenarios. Then, light signals from two areas are acquired via a light sensor or other detection device connected to the display screen. These light signals are then converted into electrical signals, which can be achieved through specific circuitry or sensor modules. Based on the intensity of the electrical signals and the area of ​​the regions, the unit area electrical signals for the two areas are calculated and denoted as the first unit area electrical signal and the second unit area electrical signal, respectively. These electrical signals reflect the luminous intensity per unit area of ​​the display screen in the two areas.

[0038] S103. Calculate the overlap of the first unit area electrical signal and the second unit area electrical signal, and determine whether the MLED display screen has a yin-yang surface based on the overlap.

[0039] Specifically, a specific algorithm is used to calculate the degree of overlap between two electrical signals per unit area. The degree of overlap can be determined by comparing the numerical values, trends, or other characteristics of the electrical signals. A low degree of overlap indicates a significant difference in luminous intensity between the two areas, potentially indicating a "yin-yang" (uneven lighting) issue on the display screen. A preset threshold or judgment standard is then used to determine whether the display screen exhibits a yin-yang problem.

[0040] S104. If there is a situation of uneven surface, the MLED beads are calibrated according to the degree of overlap.

[0041] Specifically, if an MLED display is found to have uneven lighting (negative light and negative light on one 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 LEDs to make the luminous intensities of the two areas more similar. The program can correct the LEDs by controlling the display's drive circuitry or using a specific correction algorithm.

[0042] S105, repeat S101 to S104 until the preset number of cycles is completed, and the MLED display screen does not show any unevenness.

[0043] Specifically, operations S101 to S104 are repeatedly executed until a preset number of loops are completed without any uneven lighting on the MLED display screen. In each loop, the program re-divides the display screen area, acquires the light signal, calculates the overlap, and performs corrections. If no uneven lighting occurs on the MLED display screen within the preset number of loops, the correction is considered successful, and the loop stops. Otherwise, the program continues looping until the requirement is met.

[0044] Using the above method, the LED beads of the MLED display can be automatically calibrated, thereby reducing manual operation and improving the accuracy and efficiency of calibrating the dark and light sides of the MLED display.

[0045] In one optional embodiment, obtaining a first unit area electrical signal and a second unit area electrical signal based on the electrical signal includes the following steps:

[0046] The electrical signals are amplified and filtered to obtain the first initial electrical signal V1(t) and the second initial electrical signal V2(t).

[0047] Calculate based on the number of pixels n1 and n2 corresponding to the two regions respectively. 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 weak or contain noise interference, the program uses an amplifier to amplify the signal and increase its strength for subsequent processing. Simultaneously, to remove noise and interference from the electrical signal, the program uses a filter to filter it. After amplification and filtering, a first initial electrical signal V1(t) and a second initial electrical signal V2(t) with relatively pure signal strength and appropriate intensity are obtained, corresponding to the electrical signals in the two regions, respectively.

[0049] The number of pixels, n1 and n2, in each of the two regions of the MLED display can be determined by reading the display parameters 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 region 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 in the first region. Similarly, the intensity value of the second initial electrical signal V2(t) is divided by the number of pixels in the second region to obtain the second unit area electrical signal V′2(t). In this way, the program can convert the electrical signals into an index related to the luminous intensity per unit area of ​​the display, for subsequent overlap calculations and light / shadow determination.

[0050] In one optional embodiment, the overlap degree of the first unit area electrical signal and the second unit area electrical signal is calculated, and the presence of a shadow / light condition on the MLED display screen is determined based on the overlap degree, including the following steps:

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

[0052] Compare the calculated r with the preset threshold r th Compare, if r <r th If so, it can be determined that the MLED display screen has a sun-and-shadow effect.

[0053] Specifically, the overlap between the first unit area electrical signal and the second unit area electrical signal is calculated. First, a time interval [T1, T2] is determined, which can be set according to the specific application scenario and requirements. Within this time interval, the average value of the first unit area electrical signal and the second unit area electrical signal is calculated, denoted as... and The calculation formula is: and Then, for n time points t within the time interval [T1, T2], calculate The values ​​are calculated and summed. Simultaneously, the values ​​are calculated separately. and The value is then calculated according to the correlation coefficient formula. Calculate the correlation coefficient r. The correlation coefficient r ranges from [-1, 1], and it reflects the degree of linear correlation between the two signals.

[0054] The presence of uneven lighting on an MLED display is determined based on the degree of overlap. A pre-set threshold, determined empirically or through experimental data, is used to assess this issue. If the calculated correlation coefficient is less than this threshold, it indicates a low linear correlation between the first and second unit area electrical signals, meaning a significant difference in luminous intensity per unit area between the two regions. In this case, the program determines that uneven lighting exists on the MLED display. If the correlation coefficient is greater than or equal to the threshold, the luminous intensity per unit area of ​​the two regions is considered relatively similar, and uneven lighting is not observed on the MLED display.

[0055] refer to Figure 2 In one optional embodiment, if there is a situation of uneven lighting, the MLED beads are corrected according to the degree of overlap, including the following steps:

[0056] S201. Calculate the degree of brightness non-uniformity based on the overlap, and determine the LED beads that need to be corrected based on the brightness value.

[0057] S202. Develop a calibration strategy based on the degree of brightness non-uniformity and the LED beads that need to be calibrated.

[0058] S203. Calibrate the MLED beads according to the calibration strategy.

[0059] Specifically, if an MLED display is found to have uneven brightness (both sides are shaded), the previously calculated overlap (correlation coefficient) is used to calculate the degree of brightness non-uniformity. The calculation method can be based on the difference between the overlap and the ideal overlap under perfectly uniform conditions to determine the degree of non-uniformity. Next, by analyzing the brightness values ​​of each LED, the LEDs requiring correction are identified. This can be done by comparing the brightness values ​​of LEDs in different areas with the overall average brightness value, or by using a specific algorithm to filter out LEDs with abnormal brightness, thus determining which LEDs need correction.

[0060] The intensity and priority of correction can be determined based on the degree of brightness unevenness. Significant unevenness may require a more aggressive correction strategy, while minor unevenness can be addressed with a gentler adjustment. For a specific LED requiring correction, a specific correction strategy can be developed based on its position on the display screen, the brightness of surrounding LEDs, and the overall brightness distribution. For example, correction can be achieved by adjusting the LED's brightness value, position parameters, color parameters, or by adjusting the drive current.

[0061] Finally, following the established calibration strategy, the MLED chips that require calibration are actually adjusted. This may involve communication with the display driver circuit, such as sending specific control signals to change the operating state of the chips to correct uneven brightness.

[0062] refer to Figure 3 In one optional embodiment, the degree of brightness non-uniformity is calculated based on the degree of overlap, and the lamp beads that need to be corrected are determined based on the brightness value, including the following steps:

[0063] S301, according to and The size determines the area that needs correction. Then determine The corresponding area is the area that needs to be corrected; if Then determine The corresponding area is the area that needs to be corrected;

[0064] S302, the brightness values ​​of N sampling points in the acquisition area, represented by the coordinates of the sampling points as (x... i y i And the corresponding brightness value is L ij ;

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

[0066] Four sampling points (x, y) are selected based on the points (x, y) to be calculated as needed. i y i ), (x i+1 y i ), (x i y i+1 ) and (x i+1 y i+1 ); where point (x, y) is located at 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. Interpolation coefficients in the vertical direction

[0068] The brightness value at point (x, y) is calculated using the bilinear interpolation formula, which is as follows:

[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 contour lines for brightness values ​​based on points with the same brightness value; if there is a gap between two adjacent contour lines that is less than the preset contour line spacing threshold, the MLED beads located in the area between the two adjacent contour lines and with a gap less than the preset contour line spacing threshold are identified as beads that need to be corrected.

[0071] S304. Calculate the correlation coefficient r and the preset threshold r th The difference Δr is used to characterize the degree of brightness non-uniformity.

[0072] Specifically, the first step is to determine the region where the LEDs requiring calibration are located. Compare the average values ​​of signals V′1(t) and V′2(t) within the same time interval. and The size of ). When At that time, The corresponding area is determined as the area that needs to be corrected; when At that time, The corresponding area was identified as the area requiring correction. Because in actual operation... The probability of it being true is so small that it can be ignored.

[0073] After determining the area to be corrected, brightness data is first collected from this area by selecting a series of sampling points on the LED display screen. For example, if the resolution of the LED display screen is M×N (M is the number of horizontal pixels and N is the number of vertical pixels), a uniform sampling strategy can be used to accurately depict the brightness distribution. For instance, a sampling point is selected every k pixels horizontally and every l pixels vertically. The coordinates of the horizontal sampling points are then: The coordinates of the vertical sampling point are Use L ij Indicates the coordinate (x) i y i The brightness value sampled at point (V) can be determined by the brightness detection module in conjunction 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 undergoes amplification and filtering by the signal processing module, and then the electrical signal intensity is converted into a brightness value using a pre-calibrated conversion formula. Assume the electrical signal intensity is V. ij The conversion formula can be L ij =α×V ij +β, where α and β are coefficients obtained by calibrating a standard light source with known brightness.

[0074] After collecting the brightness values ​​at discrete sampling points, an interpolation algorithm is needed to obtain the brightness value at any point on the entire display screen. Bilinear interpolation is a commonly used method. For any point (x, y) on the display screen, it is assumed to be located at four sampling points (x, y, y, y). i y i ), (x i+1 y i ), (x i y i+1 ) and (x i+1 y i+1 Between ), first calculate the interpolation coefficients in the horizontal direction. Interpolation coefficients in the vertical direction Then, the brightness value of point (x, y) is calculated using the bilinear interpolation formula, which 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 across the entire display screen can be obtained.

[0075] Draw luminance contour lines based on the luminance distribution. Assume we set a series of luminance contour line values ​​C. k (k = 1, 2, ..., n), for each C k We need to find the display screen that satisfies L(x,y)=C k All points. 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 (e.g., from left to right, from top to bottom). When a point (x, y) is found to have a brightness value L(x, y) between C k and C k+1 When interpolating between contour lines, linear interpolation is needed to determine the intersection points of contour lines with the line segments surrounding that 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 x′ of the intersection point of the contour line and the line segment [(x, y), (x+Δx, y)] can be calculated using linear interpolation, with the following formula: In this way, each brightness contour line can be drawn.

[0076] The LEDs requiring adjustment are determined based on the contour line spacing. Contour line spacing refers to the distance between two adjacent contour lines. For brightness contour lines, the spacing can be measured by the brightness difference ΔL between two adjacent contour lines. For example, if the brightness differences between two adjacent contour lines are L1 and L2, then ΔL = |L1 - L2|. A contour line spacing threshold ΔL is set. th When ΔL is less than ΔL th In this case, it can be determined that the LED beads in that area (the area between these two contour lines) need to be adjusted. This is because a smaller contour line spacing indicates a more drastic change in brightness in that area, which is likely a manifestation of the "yin-yang phenomenon" (where light and shadow appear on different sides of the face).

[0077] Calculate the correlation coefficient r and the preset threshold r th The difference Δr is used to characterize the degree of brightness non-uniformity. The larger the Δr, the greater the brightness non-uniformity, requiring a more intensive correction operation. This difference can serve as a quantitative indicator to help determine the strength and priority of the correction.

[0078] refer to Figure 4 In one optional embodiment, a calibration strategy is formulated based on the degree of brightness non-uniformity and the LEDs requiring calibration, including the following steps:

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

[0080] S402. The calibration strategy is to use each lamp bead that needs to be calibrated and its corresponding brightness adjustment ratio k and position fine adjustment amount.

[0081] Specifically, a mapping relationship is first established, which associates the degree of brightness non-uniformity with the brightness adjustment ratio and the position fine-tuning amount. The degree of brightness non-uniformity is a quantified value that reflects the magnitude of the brightness difference between different areas of the display screen.

[0082] For each LED that needs correction, the program determines the corresponding brightness adjustment ratio k and position fine-tuning amount in the mapping relationship based on the degree of brightness non-uniformity in its area. The brightness adjustment ratio k determines the extent to which the LED's brightness needs to be adjusted. For example, if k is 1.2, it means the LED's brightness needs to be increased by 20%; if k is 0.8, it means the LED's brightness needs to be decreased by 20%. The position fine-tuning amount includes horizontal fine-tuning Δx and vertical fine-tuning Δy, used to fine-tune the LED's position to improve the uniformity of brightness distribution. The horizontal fine-tuning Δx and vertical fine-tuning Δy can be pixel-level adjustments, such as moving a few pixels to the left or right, or moving a few pixels up or down.

[0083] Each LED chip requiring calibration, along with its corresponding brightness adjustment ratio k and position fine-tuning amount, is combined to form a calibration strategy. This strategy guides the actual calibration operation of the MLED chips. For example, a command can be generated based on this strategy and sent to the driver circuit, which then performs the appropriate calibration operation on the LED chip in response to the command.

[0084] In one optional embodiment, the MLED chips are calibrated according to a calibration strategy, including the following steps:

[0085] The input current of the lamp bead to be calibrated is I1, which is I2, where I2 = (1 + k)I1;

[0086] The position of the LED bead to be corrected is moved based on the horizontal fine adjustment Δx and the vertical fine adjustment Δy.

[0087] Specifically, the first step is to identify the LEDs that need calibration. For each LED, the program obtains its current input current I1. Based on the brightness adjustment ratio k determined in the calibration strategy, the program calculates the calibrated current I2. The formula I2 = (1 + k)I1 means that if k is positive, the calibrated current will be greater than the original current, thus increasing the LED's brightness; if k is negative, the calibrated current will be less than the original current, thus decreasing the LED's brightness. By adjusting the input current of the LEDs, the program regulates their brightness to improve 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 optional 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 a division threshold T, where 0 < T < 1;

[0092] For each pixel point, if X ij < T, divide the pixel point into region A; if X ij ≥ T, divide the pixel point 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, divide the pixel point into region B. In this way, all pixel points on the display screen are randomly divided into two regions.

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

[0097] Specifically, after calibrating the LEDs, the brightness changes before and after calibration can be compared. The brightness trend of the two areas before and after calibration can be displayed in a chart, or the increase or decrease in brightness value can be directly shown. For LEDs requiring calibration, their calibrated brightness value should be highlighted, along with a comparison with the brightness of surrounding LEDs, to verify whether the calibration effect meets expectations.

[0098] If the LED positions are fine-tuned, the changes can be displayed graphically. For example, on a simulated image on the display screen, different colors or markers can be used to represent the LED positions before and after correction, allowing users to intuitively see the effect of the position fine-tuning. This demonstrates whether the layout of the LEDs with surrounding LEDs is more reasonable after the position fine-tuning, and the impact on brightness uniformity.

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

[0100] It should be understood that although the steps in the flowcharts of the embodiments described above are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the embodiments described above may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages of other steps.

[0101] Based on the same inventive concept, this application also provides an automatic MLED display screen eccentricity correction device for implementing the above-mentioned automatic MLED display screen eccentricity correction method. The solution provided by this device is similar to the solution described in the above method. Therefore, the specific limitations of one or more MLED display screen eccentricity correction device embodiments provided below can be found in the limitations of the MLED display screen eccentricity correction method described above, and will not be repeated here.

[0102] In one exemplary embodiment, such as Figure 3 As shown, an automatic correction device 400 for the shadow and light areas of an MLED display screen is provided. The device includes:

[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 random brightness values, acquire the light signals of the two regions respectively, convert the light signals into electrical signals, and obtain a first unit area electrical signal and a second unit area electrical signal based on 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 regions.

[0105] The judgment module 403 is used to calculate the overlap between the first unit area electrical signal and the second unit area electrical signal, and to determine whether the MLED display screen has a yin-yang surface condition based on the overlap.

[0106] The calibration module 404 is used to calibrate the MLED beads according to the degree of overlap when the yin-yang situation exists.

[0107] The loop module 405 is used to control the above module to run in a loop until the preset number of loops has been completed, and the MLED display screen does not show any unevenness.

[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 the first initial electrical signal V1(t) and the second initial electrical signal V2(t).

[0110] The unit for calculating electrical signals per unit area is used to calculate the signal based on the number of pixels n1 and n2 corresponding to the two regions, respectively. 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 judgment module 403 includes:

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

[0113] The yin-yang face determination unit is used to compare the calculated r with the preset threshold r. th Compare, if r <r thIf so, it can be determined that the MLED display screen has a sun-and-shadow effect.

[0114] Optionally, the calibration module 404 includes:

[0115] The brightness non-uniformity calculation and lamp bead determination unit is used to calculate the brightness non-uniformity based on the overlap and determine the lamp beads that need to be corrected based on the brightness value.

[0116] The calibration strategy formulation unit is used to formulate a calibration strategy based on the degree of brightness non-uniformity and the LED beads that need to be calibrated.

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

[0118] Optionally, the unit for calculating brightness non-uniformity and determining the LED chips requiring correction is specifically used to perform the following operations, including:

[0119] Step 1, according to and The size determines the area that needs correction; if Then determine The corresponding area is the area that needs to be corrected.

[0120] Step 2: Collect the brightness values ​​of N sampling points in the acquisition area, and represent the coordinates of the sampling points as (x, y, y). 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) at any point (x, y) in the region, including:

[0122] Four sampling points (x, y) are selected based on the points (x, y) to be calculated as needed. i y i ), (x i+1 y i ), (x i y i+1 ) and (x i+1 y i+1 ); where point (x, y) is located at 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. Interpolation coefficients in the vertical direction

[0124] The brightness value at point (x, y) is calculated using the bilinear interpolation formula, which is as follows:

[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 contour lines for brightness values ​​based on points with the same brightness value; if there is a gap between two adjacent contour lines that is less than the preset contour line spacing threshold, the MLED beads located in the area between the two adjacent contour lines and with a gap less than the preset contour line spacing threshold are identified as beads that need to be corrected.

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

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

[0129] For each LED chip that needs to be calibrated, based on the pre-established mapping relationship between the brightness non-uniformity Δr and the brightness adjustment ratio and position fine-tuning amount, the brightness adjustment ratio k and position fine-tuning amount corresponding to each LED chip that needs to be calibrated are obtained according to the brightness non-uniformity Δr; the position fine-tuning amount includes the horizontal fine-tuning amount Δx and the vertical fine-tuning amount Δy.

[0130] The calibration strategy is to use each LED bead that needs to be calibrated, its corresponding brightness adjustment ratio k, and its position fine-tuning amount.

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

[0132] The input current of the lamp bead to be calibrated is I1, which is I2, where I2 = (1 + k)I1;

[0133] The position of the LED bead to be corrected is moved based on the horizontal fine adjustment Δx and the vertical fine adjustment Δy.

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

[0135] This application embodiment also provides an automatic correction system for the light and dark sides of an MLED display screen, the system including: an MLED display screen, a light receiver, a signal processor, a server, and a controller;

[0136] The server connects to the MLED display to obtain the pixel layout information of the MLED display; based on the layout information, it randomly divides the MLED display into two areas; the server is also used to control the display of the MLED screen.

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

[0138] The signal processor is connected to the server. The signal processor processes the electrical signal to obtain a first unit area electrical signal and a second unit area electrical signal, and sends the first unit area electrical signal and the second unit area electrical signal to the server. 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 regions.

[0139] The server is also connected to the controller to calculate the overlap of the first unit area electrical signal and the second unit area electrical signal, and to determine whether the MLED display screen has a yin-yang surface condition based on the overlap. If a yin-yang surface condition exists, a correction command is generated based on the overlap and sent to the controller.

[0140] The controller responds to the received calibration command and calibrates the MLED beads;

[0141] The server is also connected to the light receiver and is used to control the MLED display, light receiver, signal processor and controller to operate in a loop to achieve the method described in any of the above methods until the preset number of loops has been continuously completed without any unevenness on the MLED display.

[0142] Specifically, an MLED display screen can be a large screen spliced ​​together from multiple MLED modules, each module containing tens of thousands of miniature LED beads; the light receiver can be a photoelectric sensor such as a photodiode, phototransistor, or photomultiplier tube; the signal processor can be a dedicated electronic circuit board containing analog signal processing circuits and an analog-to-digital converter (ADC); the server can be a high-performance computer or industrial control computer (IPC) with sufficient computing and storage capabilities, 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 controllers.

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

[0144] For the device embodiments, since they basically correspond to the method embodiments, the relevant parts can be referred to in the description of the method embodiments. The device embodiments described above are merely illustrative. The components described as separate parts may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this disclosure according to actual needs. Those skilled in the art can understand and implement this without creative effort.

[0145] The above-described embodiments are merely illustrative of several implementation methods of the embodiments of this application, and their descriptions are relatively specific and detailed. However, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the embodiments of this application, and these modifications and improvements all fall within the protection scope of the embodiments of this application.

Claims

1. A method for automatic correction of the uneven surface of an MLED display screen, characterized in that, The method includes: S1. Randomly divide the MLED display screen into two areas; S2. Control the MLED display screen to display a full white image with random brightness values, and acquire the light signals of the two regions respectively; convert the light signals into electrical signals, and obtain a first unit area electrical signal and a second unit area electrical signal based on 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 regions; S3. 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 yin-yang surface based on the overlap. S4. If the aforementioned yin-yang surface situation exists, the MLED beads are corrected according to the degree of overlap; S5, repeat S1 to S4 until the preset number of cycles has been completed, and no yin-yang situation occurs.

2. The method according to claim 1, characterized in that, Obtaining a first unit area electrical signal and a second unit area electrical signal based on the electrical signal includes: The electrical signal is amplified and filtered to obtain a first initial electrical signal. Second initial electrical signal ; Based on the number of pixels corresponding to the two regions respectively and ,calculate and The first unit area electrical signal and the second unit area electrical signal are denoted as... .

3. The method according to claim 2, characterized in that, The calculation of the overlap between the first unit area electrical signal and the second unit area electrical signal, and the determination of whether the MLED display screen has a sunken or shaded surface based on the overlap, includes: Calculate the correlation coefficient between the first unit area electrical signal and the second unit area electrical signal. The calculation formula is: ;in, and These are signals and The average value over the same time interval. The range of values ​​for is ; The calculated With preset threshold If a comparison is made, If so, it is determined that the MLED display screen has a yin-yang surface.

4. The method according to claim 3, characterized in that, If the aforementioned uneven surface condition exists, the MLED beads are corrected according to the degree of overlap, including: The degree of brightness non-uniformity is calculated based on the overlap, and the lamp beads that need to be corrected are determined based on the brightness value; Based on the degree of brightness non-uniformity and the lamp beads that need to be calibrated, a calibration strategy is formulated; The MLED chips are calibrated according to the calibration strategy described above.

5. The method according to any one of claims 4, characterized in that, The step of calculating the degree of brightness non-uniformity based on the overlap and determining the LED beads that need to be corrected based on the brightness value includes: Step 1, according to and The size determines the area that needs correction. Then determine The corresponding area is the area that needs to be corrected; if Then determine The corresponding area is the area that needs to be corrected; Step 2: Collect data from the area. The brightness value of each sampling point, and the coordinates of the sampling points are represented as follows: And the corresponding brightness value ; Step 3: Use bilinear interpolation to calculate the value at any point in the region. brightness value ,include: Points to be calculated as needed Select four sampling points , , and ; wherein, the point Located at the sampling point , , and between; Calculate the interpolation coefficients in the horizontal direction. Interpolation coefficients in the vertical direction ; Calculated using the bilinear interpolation formula The brightness value of a point is calculated using the following formula: ; Draw contour lines for brightness values ​​based on points with the same brightness value; if there is a gap between two adjacent contour lines that is less than a preset contour line spacing threshold, the MLED beads located in the area between the two adjacent contour lines and with a gap less than the preset contour line spacing threshold are identified as beads that need to be corrected. Step 4: Calculate the correlation coefficient. With the preset threshold The difference ,use Characterizes the degree of brightness non-uniformity.

6. The method according to claim 5, characterized in that, The step of formulating a correction strategy based on the degree of brightness non-uniformity and the LED beads requiring correction includes: For each of the aforementioned LED beads requiring calibration, based on a pre-established degree of brightness non-uniformity... The mapping relationship between the brightness adjustment ratio and the position fine-tuning amount, based on the degree of brightness non-uniformity. Obtain the brightness adjustment ratio corresponding to each of the aforementioned LED beads that need to be calibrated. and position fine-tuning amount; the position fine-tuning amount includes horizontal fine-tuning amount. and vertical fine adjustment amount ; Each of the lamp beads requiring calibration and its corresponding brightness adjustment ratio. The position fine-tuning amount is used as the correction strategy.

7. The method according to claim 6, characterized in that, The calibration of the MLED chips according to the calibration strategy includes: The input current of the lamp bead that needs to be calibrated Correction to , ; According to the aforementioned horizontal fine-tuning amount and the vertical fine adjustment amount The position of the lamp bead that needs to be corrected is moved.

8. The method according to claim 2, characterized in that, The process of randomly dividing the MLED display screen into two areas includes: Assign a random value to each pixel. ;in, It is in A random number that is uniformly distributed within an interval; Randomly set the division threshold ,in ; For each pixel, if Then the pixel is divided into regions. ;like Then the pixel is divided into regions. .

9. An automatic correction device for the eccentricity of an MLED display screen, characterized in that, The device includes: The area division module is used to randomly divide the MLED display screen into two areas; The signal acquisition and processing module is used to control the MLED display screen to display a full white image with random brightness values, acquire the light signals of the two regions respectively; convert the light signals into electrical signals, and obtain a first unit area electrical signal and a second unit area electrical signal based on 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 regions; The judgment module is used to calculate the overlap between the first unit area electrical signal and the second unit area electrical signal, and to determine whether the MLED display screen has a yin-yang surface based on the overlap. The calibration module is used to calibrate the MLED beads according to the degree of overlap when the yin-yang situation exists; The loop module is used to control the above modules to run in a loop until the preset number of loops has been completed, and the MLED display screen does not show any unevenness.

10. An automatic correction system for the yin-yang surfaces of an MLED display screen, characterized in that, The system includes: an MLED display screen, a light receiver, a signal processor, a server, and a controller; The server is connected to the MLED display screen and is used to obtain the pixel layout information 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 light receiver is connected to and installed above the signal processor; the light receiver is used to receive the light signals when the two areas of the MLED display screen display a full white image with random brightness values, convert the light signals into electrical signals, and send the electrical signals to the signal processor. The signal processor is connected to the server. The signal processor processes the electrical signal to obtain a first unit area electrical signal and a second unit area electrical signal, and sends the first unit area electrical signal and the second unit area electrical signal to the server. 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 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 to determine whether the MLED display screen has a yin-yang surface condition based on the overlap. If a yin-yang surface condition exists, a correction instruction is generated based on the overlap and the correction instruction is sent to the controller. The controller calibrates the MLED beads in response to the received calibration command; The server is also connected to the light receiver and is used to control the MLED display screen, the light receiver, the signal processor and the controller to operate in a loop to achieve the method described in any one of claims 1-8, until a preset number of loops have been continuously completed and the MLED display screen does not exhibit any unevenness.

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