Brightness compensation method and brightness compensation device of display panel

Abstract

The present disclosure provides a display panel brightness compensation method and a display panel brightness compensation device. The method comprises: dividing a display panel into M first regions, and dividing at least part of the first regions into N second regions; wherein M and N are natural numbers greater than 1; determining a target region in the N second regions using a quadtree decomposition method; obtaining a brightness value and / or a grayscale value of a sub-pixel of the target region; obtaining a brightness compensation value of the target region based on the brightness value and / or the grayscale value and a preset gamma curve, and performing brightness compensation on the target region based on the brightness compensation value. The brightness compensation method can perform more refined target region positioning, can ensure the compensation effect of Mura with a larger area, has a good improvement effect on fine Mura, and is convenient for comparing the display effects before and after improvement.

Description

Technical Field

[0001] This invention relates to the field of display technology, and in particular to a brightness compensation method and device for a display panel. Background Technology

[0002] With the development of display technology, display panels are being used more and more widely. However, due to factors such as the precision of display panel production equipment and manufacturing processes, display panels often suffer from display mura (i.e., uneven brightness), which affects the uniformity of the display. Summary of the Invention

[0003] The brightness compensation method and brightness compensation device for the display panel disclosed herein are intended to solve the problem of display mura (i.e., uneven brightness) that commonly exists in existing display panels.

[0004] To address the aforementioned technical problems, this disclosure provides a method for brightness compensation of a display panel. The method includes: dividing the display panel into M first regions, and further dividing at least a portion of the first regions into N second regions; where M and N are natural numbers greater than 1; determining target regions among the N second regions using a quadtree decomposition method; obtaining the brightness and / or grayscale values ​​of the sub-pixels of the target regions; obtaining brightness compensation values ​​for the target regions based on the brightness and / or grayscale values ​​and a preset gamma curve; and performing brightness compensation on the target regions based on the brightness compensation values.

[0005] The steps for determining the target region among the N second regions using the quadtree decomposition method include:

[0006] Obtain the brightness and / or grayscale value of each sub-pixel in at least a portion of the second region;

[0007] The gray level of the second region is determined based on the brightness value and / or gray value of each sub-pixel in the second region;

[0008] If the gray level of the second region is a preset level and the current number of splits is less than the number of splits threshold, then the second region is split into multiple sub-regions and the number of splits is increased by one; the sub-regions are used as new second regions, and the process is returned to obtain the brightness value and / or gray value of each sub-pixel in at least a portion of the second region;

[0009] If the gray level of the second region is a preset level and the current number of splits is equal to the number of splits threshold, then the second region is determined as the target region.

[0010] Preferably, if the gray level of the second region is not a preset level, then the second region is determined not to be the target region.

[0011] The step of determining the grayscale level of the second region based on the brightness value and / or grayscale value of each sub-pixel in the second region includes:

[0012] Based on the gray value of each sub-pixel in the second region, obtain the first mean of the gray values ​​of all sub-pixels in the second region; and based on the first mean of the gray values ​​of each second region, obtain the second mean and the first variance of the gray values ​​of the first region.

[0013] The gray level of the second region is determined based on the gray value of each sub-pixel in the second region, the second mean, and the first variance.

[0014] The step of determining the gray level of the second region based on the gray value, second mean, and variance of each sub-pixel in the second region includes:

[0015] Obtain the absolute value of the first difference between the grayscale value of each sub-pixel in the second region and the second mean of the first region;

[0016] Calculate the ratio of the number of sub-pixels in the second region whose absolute value of the first difference is greater than W times the first variance to the total number of sub-pixels in the second region; where W is a positive number;

[0017] If the ratio is greater than or equal to the first threshold, the gray level of the second region is determined to be the preset level.

[0018] The step of determining the grayscale level of the second region based on the brightness value and / or grayscale value of each sub-pixel in the second region includes:

[0019] Based on the brightness value of each sub-pixel in the second region, obtain the third mean of the brightness values ​​of all sub-pixels in the second region; and based on the third mean of the brightness values ​​of each second region, obtain the fourth mean and the second variance of the brightness values ​​of the first region.

[0020] The gray level of the second region is determined based on the brightness value, fourth mean, and second variance of each sub-pixel in the second region.

[0021] The step of determining the grayscale level of the second region based on the brightness value, fourth mean, and second variance of each sub-pixel in the second region includes:

[0022] Obtain the absolute value of the second difference between the brightness value of each sub-pixel in the second region and the fourth mean value of the first region;

[0023] Calculate the ratio of the number of sub-pixels in the second region whose absolute value of the second difference is greater than W times the second variance to the total number of sub-pixels in the second region; where W is a positive number;

[0024] If the ratio is greater than or equal to the first threshold, the gray level of the second region is determined to be the preset level.

[0025] The step of obtaining the brightness compensation value of the target area based on the brightness value and / or grayscale value and a preset gamma curve includes:

[0026] Fit the brightness and / or grayscale values ​​of the target area to obtain the actual Gamma curve of the target area;

[0027] The actual Gamma curve is compared with the preset Gamma curve to obtain the brightness compensation value.

[0028] To solve the aforementioned technical problems, another technical solution adopted in this disclosure is: providing a brightness compensation device for a display panel. The device includes: a region division module, a target region determination module, a detection module, and a compensation module; wherein, the region division module is used to divide the display panel into M first regions, and at least a portion of the first regions into N second regions; where M and N are natural numbers greater than 1; the target region determination module is used to determine the target region among the N second regions using a quadtree decomposition method; the detection module is used to obtain the brightness value and / or grayscale value of the sub-pixels of the target region; the compensation module is used to obtain the brightness compensation value of the target region based on the brightness value and / or grayscale value and a preset gamma curve, and to perform brightness compensation on the target region based on the brightness compensation value.

[0029] The target area determination module includes:

[0030] A detection unit is used to acquire the brightness value and / or grayscale value of each sub-pixel in at least a portion of the second region;

[0031] A gray level determination unit is used to determine the gray level of the second region based on the brightness value and / or gray level value of each sub-pixel in the second region;

[0032] The target region determination unit is configured to, in response to the gray level of the second region being a preset level and the current number of splits being less than a threshold, split the second region into multiple sub-regions, use the sub-regions as new second regions, and return the brightness value and / or gray value of each sub-pixel in at least a portion of the second region obtained by the detection unit; and increment the number of splits by one; in response to the gray level of the second region being a preset level and the current number of splits being equal to the threshold, determine the second region as the target region.

[0033] The gray level determination unit is further configured to obtain a first mean of gray values ​​of all sub-pixels in the second region based on the gray value of each sub-pixel in the second region; and obtain a second mean and a first variance of gray values ​​in the first region based on the first mean of gray values ​​in each second region; and determine the gray level of the second region based on the gray value, the second mean, and the first variance of each sub-pixel in the second region.

[0034] Alternatively, the grayscale level determination unit is further configured to obtain a third mean of the brightness values ​​of all sub-pixels in the second region based on the brightness value of each sub-pixel in the second region; and obtain a fourth mean and a second variance of the brightness values ​​of the first region based on the third mean of the brightness values ​​of each second region; and determine the grayscale level of the second region based on the brightness value, the fourth mean, and the second variance of each sub-pixel in the second region.

[0035] The beneficial effects of this disclosure, which differ from the prior art, are as follows: The brightness compensation method and device for the display panel provided in this disclosure first divide the display panel into M first regions, and further divide at least a portion of the first regions into N second regions; then, a quadtree decomposition method is used to determine the target region among the N second regions; compared with the scheme of directly determining the target region from the first region or the entire display panel, more refined target region positioning can be performed; then, the brightness value and / or grayscale value of the sub-pixels of the target region and a preset gamma curve are obtained; and based on the brightness value and / or grayscale value, the brightness compensation value of the target region is obtained, and the brightness compensation of the target region is performed based on the brightness compensation value; thus, the compensation effect of large-area mura can be guaranteed, and the accuracy requirements of fine mura compensation can also be met, with better improvement effect of fine mura; at the same time, it is convenient to compare the display effect before and after improvement. Attached Figure Description

[0036] Figure 1 A flowchart illustrating a brightness compensation method for a display panel according to an embodiment of this disclosure;

[0037] Figure 2 This is a diagram illustrating the area division of the display panel;

[0038] Figure 3 for Figure 1 Sub-flowchart of step S2;

[0039] Figure 4 A simplified structural diagram of a brightness compensation device for a display panel provided in an embodiment of this disclosure;

[0040] Figure 5 A simplified structural diagram of a brightness compensation device for a display panel provided in another embodiment of this disclosure. Detailed Implementation

[0041] The technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this disclosure, and not all of them. Based on the embodiments of this disclosure, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this disclosure.

[0042] The terms "first," "second," and "third" in this disclosure are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first," "second," or "third" may explicitly or implicitly include at least one of that feature. In the description of this disclosure, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified. All directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of this disclosure are only used to explain the relative positional relationships and movements between components in a specific orientation (as shown in the figures). If the specific orientation changes, the directional indications also change accordingly. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products, or devices.

[0043] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this disclosure. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0044] In related technologies, to eliminate mura (demura), the brightness data of sub-pixels is typically extracted from different grayscale images of the entire display panel, gamma curves are fitted, and compared with a target gamma curve to obtain a brightness compensation value and compensate for the brightness. However, existing demura solutions are effective at improving large-area mura, but the improvement effect on subtle mura is not obvious; at the same time, a clear comparison of the improvement effect before and after demura cannot be made.

[0045] Based on this, embodiments of this application provide a brightness compensation method for a display panel, which can improve the above situation, as detailed below.

[0046] The present disclosure will now be described in detail with reference to the accompanying drawings and embodiments.

[0047] Please see Figure 1 , Figure 1 This is a flowchart illustrating a brightness compensation method for a display panel according to an embodiment of the present disclosure. In this embodiment, a brightness compensation method for a display panel is provided, the method comprising:

[0048] Step S1: Divide the display panel into M first regions, and divide at least a portion of the first regions into N second regions; where M and N are natural numbers greater than 1; specifically, M and N are natural numbers greater than 2.

[0049] Taking an example where both M and N are 4, the display panel is divided into M first regions R, and each first region R is further divided into N second regions Ri. For details, please refer to [link to relevant documentation]. Figure 2 , Figure 2 This is a schematic diagram of the display panel's area division. In a specific implementation, the display panel is divided into M first regions R, and then each first region R is divided into N second regions Ri; alternatively, only the first region R with the display Mura problem can be further divided into N second regions Ri to simplify the compensation process.

[0050] In this system, the areas of the M first regions R can be the same or different, or some of the first regions R may have the same area while the remaining areas may be different. The areas of the N second regions Ri are the same, which facilitates labeling each second region Ri for subsequent tracing. Of course, the areas of the N second regions Ri may also be different; or, some of the N second regions Ri may have the same area while the remaining areas may be different.

[0051] Those skilled in the art will understand that directly dividing the display panel into multiple checkerboard grids makes it impossible to determine the side length of each small grid, thus making it impossible to accurately locate the Mura region. However, this disclosure first divides the display area of ​​the display panel into M checkerboard grids, and then divides each checkerboard grid into N small regions, enabling rapid and refined target pixel localization from the grayscale image acquired by the CCD camera in subsequent steps.

[0052] Step S2: Use the quadtree decomposition method to determine the target region in the N second regions.

[0053] The quadtree decomposition method refers to dividing a region into multiple subregions, which can be arranged in a multi-row, multi-column array. For example, it can be four subregions arranged in two rows and two columns. If one of the subregions meets the splitting condition, then this subregion is split into four new subregions, and so on, until the number of splits reaches the threshold. Then, the new subregions that meet the condition are determined as the target region.

[0054] Step S3: Obtain the brightness value and / or grayscale value of the sub-pixels of the target region.

[0055] Specifically, an image acquisition device can be used to acquire a grayscale image of the target area, and then the grayscale values ​​of several R / G / B sub-pixels in the grayscale image can be obtained. The image acquisition device can be a CCD camera, etc. Specifically, multiple grayscale images from low to high can be acquired using the image acquisition device, for example, acquiring five grayscale images: 32, 64, 96, 160, and 192. Since different sub-pixels have different luminous efficiencies and areas, in a specific embodiment, the exposure time can be adjusted according to the actual situation to acquire grayscale images within a preset grayscale range, which can be 80-220. The actual brightness value corresponding to the grayscale value of the sub-pixels in the target area can be determined based on the conversion relationship between grayscale values ​​and brightness values, and the grayscale values ​​in the sub-pixel image of the target area acquired by the image acquisition device. The brightness value of the sub-pixels in the target area can be calculated based on the grayscale values ​​of the sub-pixels in the target area according to the conversion relationship between grayscale values ​​and brightness values. Alternatively, the brightness value of the target area when displaying different grayscale images can be directly obtained using a brightness measurement device.

[0056] Step S4: Based on the brightness value and / or grayscale value and the preset gamma curve, obtain the brightness compensation value of the target area, and perform brightness compensation on the target area based on the brightness compensation value.

[0057] Specifically, the target brightness value corresponding to each gray level can be obtained based on a preset gamma curve. The actual brightness value and / or grayscale value of the sub-pixels in the target region is compared with the target brightness value to determine the brightness compensation value of the target region.

[0058] In the specific implementation process, step S4 specifically includes:

[0059] Step S41: Fit the brightness and / or grayscale values ​​of the target area to obtain the actual Gamma curve of the target area.

[0060] In the specific implementation process, the brightness values ​​and / or grayscale values ​​corresponding to the various grayscale images collected in step S3 can be fitted to obtain the corresponding Gamma curve (i.e., the correspondence between grayscale and brightness), and finally the corresponding brightness compensation is performed.

[0061] This involves obtaining one of the brightness and grayscale values ​​of several R / G / B sub-pixels in the target area to perform gamma curve fitting, thereby obtaining the actual gamma curve; for example, obtaining the brightness values ​​of several R / G / B sub-pixels in the target area to perform gamma curve fitting, thereby obtaining the actual gamma curve.

[0062] Step S42: Compare the actual Gamma curve with the preset Gamma curve to obtain the brightness compensation value.

[0063] Specifically, the brightness and / or grayscale values ​​of the sub-pixels in the target area are used to fit the Gamma curve to determine the amount of compensation change in the target area, and the brightness compensation is performed on the target area based on the brightness compensation value. This can ensure the compensation effect of large-area Mura and also meet the accuracy requirements of fine Mura compensation. The improvement effect of fine Mura is better, which effectively improves the uniformity of the display panel.

[0064] The other specific implementation processes of steps S41 and S42 are the same as or similar to the existing Gamma curve fitting and the specific implementation processes of comparing the Gamma curve with the standard Gamma curve to obtain the brightness compensation value, and can achieve the same or similar technical effects. For details, please refer to the prior art, which will not be repeated here.

[0065] The brightness compensation method for the display panel provided in this embodiment first divides the display panel into M first regions R, and further divides at least a portion of the first regions R into N second regions Ri; then, it uses a quadtree decomposition method to determine the target region among the N second regions Ri; compared with the scheme of directly determining the target region from the first region or the entire display panel, it can perform more refined target region positioning; then, it obtains the brightness value and / or grayscale value of the sub-pixels of the target region; and based on the brightness value and / or grayscale value, it obtains the brightness compensation value of the target region, and performs brightness compensation on the target region based on the brightness compensation value; in this way, it can ensure the compensation effect of large-area Mura, and also meet the accuracy requirements of fine Mura compensation, with better improvement effect of fine Mura, and at the same time, it is easy to compare the display effect before and after improvement.

[0066] In one specific implementation, see Figure 3 , Figure 3 for Figure 1 The sub-flowchart of step S2; step S2 specifically includes:

[0067] Step S21: Obtain the luminance value and / or grayscale value of each sub-pixel in at least a portion of the second region.

[0068] Specifically, based on the visually perceptible differences in brightness among the N second regions Ri, the brightness and / or grayscale values ​​of only the second regions Ri with more pronounced display Mura issues can be fitted. Alternatively, to improve the overall display uniformity of the display panel, the brightness and / or grayscale values ​​of each second region Ri can also be fitted.

[0069] The specific implementation process of step S21 is the same as or similar to the specific implementation process of step S3 in the above embodiments, and can achieve the same or similar technical effects. For details, please refer to the above text, and will not be repeated here.

[0070] Step S22: Determine the gray level of the second region based on the brightness value and / or gray value of the sub-pixels of the second region.

[0071] Among them, grayscale levels can represent the degree of unevenness in display.

[0072] In one embodiment, step S22 specifically includes:

[0073] Step S221a: Based on the gray value of each sub-pixel in the second region Ri, obtain the first mean of the gray values ​​of all sub-pixels in the second region Ri; and based on the first mean of the gray values ​​of each second region Ri, obtain the second mean and the first variance of the gray values ​​of the first region R.

[0074] Specifically, the mean of the grayscale values ​​of all sub-pixels in the acquired second region Ri is calculated as the first mean of the grayscale values ​​in the current second region Ri. The mean of the first means of all second regions Ri is then calculated as the second mean of the first region R.

[0075] For example, a first region R includes four second regions Ri of equal area, and the first mean gray values ​​of the four second regions Ri are A1, A2, A3, and A4, respectively; then the second mean of the first region R containing these four second regions Ri is... The first variance of the gray values ​​in the first region R

[0076] Step S222a: Determine the gray level of the second region Ri based on the gray value, second mean, and first variance of each sub-pixel in the second region Ri.

[0077] In the specific implementation process, step S222a specifically includes:

[0078] Step A1: Obtain the absolute value of the first difference between the gray value of each sub-pixel in the second region Ri and the second mean of the first region R.

[0079] Continuing with the above embodiment as an example, assume that the second region Ri includes E sub-pixels, and the gray values ​​corresponding to each sub-pixel are a1, a2, a3...aE respectively; the absolute values ​​Δm1, Δm2, Δm3, Δm4...ΔmE of the first difference between the gray values ​​(a1, a2, a3...aE) of each sub-pixel in the second region Ri and the second mean (x) of the gray values ​​in the first region R are respectively Δm1=|a1-x|, Δm2=|a2-x|, Δm3=|a3-x|, Δm4=|a4-x|...ΔmE=|aE-x|.

[0080] Step B1: Calculate the ratio of the number of sub-pixels in the second region Ri whose absolute value of the first difference is greater than W times the first variance to the total number of sub-pixels in the second region Ri.

[0081] Where W is a positive number, for example, W can be 1, 1.5, 2, 3, etc.

[0082] Step C1: In response to the ratio being greater than or equal to the first threshold, the gray level of the second region Ri is determined to be the preset level.

[0083] Step D1: In response to the ratio being less than the first threshold, it is determined that the gray level of the second region Ri is not the preset level, and therefore the second region Ri is not the target region.

[0084] It is understandable that if the second region Ri, whose grayscale level is not the preset level, displays normally, then there is no need to further split this second region Ri. Since this second region Ri is not the target region (i.e., a non-mura region), there is no need to perform brightness compensation on this non-target region. By distinguishing between the target region and the non-target region, an effective comparison can be made before and after the improvement of the mura region of the display panel; and there is no need to perform gamma curve fitting on the non-target region, which simplifies the compensation process and speeds up the compensation efficiency. The first threshold can be 40%, 60%, 70%, or 80%, and can be set according to the actual situation; this application does not limit it in this regard.

[0085] In another embodiment, step S22 specifically includes:

[0086] Step S221b: Based on the brightness value of each sub-pixel in the second region Ri, obtain the third mean of the brightness values ​​of all sub-pixels in the second region Ri; and based on the third mean of the brightness values ​​of each second region Ri, obtain the fourth mean and the second variance of the brightness values ​​of the first region R.

[0087] Specifically, the average brightness value of all sub-pixels in the acquired second region Ri is calculated as the third average brightness value of the current second region Ri. The average of the third average values ​​of all second regions Ri is then calculated as the fourth average brightness value of the first region R.

[0088] For example, a first region R includes four second regions Ri of equal area, and the third mean values ​​of the brightness values ​​of the four second regions Ri are B1, B2, B3, and B4, respectively; then the fourth mean value of the brightness values ​​of the first region R containing these four second regions Ri is... The second variance of the brightness values ​​in the first region R

[0089] Step S222b: Determine the gray level of the second region Ri based on the brightness value, fourth mean, and second variance of each sub-pixel in the second region Ri.

[0090] In the specific implementation process, step S222b specifically includes:

[0091] Step A2: Obtain the absolute value of the second difference between the brightness value of each sub-pixel in the second region Ri and the fourth mean of the first region R.

[0092] Continuing with the above embodiment as an example, assume that the second region Ri includes E sub-pixels, and the brightness values ​​corresponding to each sub-pixel are b1, b2, b3...bE respectively; the absolute values ​​Δm1, Δm2, Δm3, Δm4...ΔmE of the second difference between the brightness value (b1, b2, b3...bE) of each sub-pixel in the second region Ri and the fourth mean (x) of the brightness value in the first region R are Δm1=|b1-x|, Δm2=|b2-x|, Δm3=|b3-x|, Δm4=|b4-x|...ΔmE=|bE-x| respectively.

[0093] Step B2: Calculate the ratio of the number of sub-pixels in the second region Ri whose absolute value of the second difference is greater than W times the second variance to the total number of sub-pixels in the second region Ri.

[0094] Here, W is a positive number; for example, W can be 1, 1.5, 2, 3, etc. Specifically, the value of W can be the same as the value of N, which can improve the accuracy of the result of determining the target area based on the above ratio.

[0095] Step C2: In response to the ratio being greater than or equal to the first threshold, the gray level of the second region Ri is determined to be the preset level.

[0096] Step D2: In response to the ratio being less than the first threshold, it is determined that the gray level of the second region Ri is not the preset level, and the second region Ri is determined not to be the target region.

[0097] If the second region Ri, whose grayscale level is not the preset level, displays normally, then there is no need to further split the second region Ri. Since the second region Ri is not the target region (i.e., a non-mura region), there is no need to perform brightness compensation on it.

[0098] Of course, step S22 may include both steps S221a-S222a and steps S221b-S222b; wherein steps S221a-S222a and S221b-S222b are not in any particular order, so as to improve the accuracy of determining whether the second region is the target region.

[0099] Step S23: In response to the fact that the gray level of the second region is a preset level and the current number of splits is less than the threshold, the second region is split into multiple sub-regions, and the number of splits is increased by one; the sub-regions are used as new second regions. Then return to execute step S21.

[0100] The current number of splits can be the number of splits performed on the second region Ri, where the number threshold can be greater than or equal to 1, for example, splitting at least a portion of the second region once or multiple times. The current number of splits can also be the number of splits performed on the display panel, where the number threshold can be greater than or equal to 2, for example, not splitting any of the second regions. The number threshold can be 2, 20, 50, 100, 200, etc., and can be set according to actual conditions; this application does not limit this. If the grayscale level of the second region is not a preset level, then the second region is determined not to be the target region.

[0101] Step S24: In response to the fact that the gray level of the second region is a preset level and the current number of splits is equal to the number of splits threshold, the second region is determined as the target region.

[0102] In the specific implementation process, the improvement effects before and after demura are further compared, especially the improvement in subtle demura areas, for subsequent analysis. The above-described solution in this embodiment has a good effect on improving subtle demura and allows for effective comparison of the demura areas of the display panel before and after improvement.

[0103] The brightness compensation method for a display panel provided in this embodiment, based on the checkerboard positioning of dividing the display panel into M first regions R, further divides at least a portion of the first regions R into N second regions Ri. This allows for more refined target area selection after obtaining the sub-pixel grayscale data and / or brightness data of the second regions Ri. Compared to methods that directly determine whether the first region R or the entire display panel has a display mura problem, this method can accurately locate the mura area of ​​the display panel, facilitating subsequent comparison of the display effect before and after brightness compensation improvement. After determining the target area, the brightness value and / or grayscale value of the target area are fitted to obtain the actual Gamma curve of the target area; then, the actual Gamma curve is compared with a preset Gamma curve to obtain a brightness compensation value, and brightness compensation is performed on the target area based on the brightness compensation value. Specifically, using the brightness value and / or grayscale value of the second regions Ri for fitting to determine the amount of compensation change in the target area ensures the compensation effect for larger mura areas while also meeting the accuracy requirements for fine mura compensation, resulting in a better improvement effect.

[0104] See Figure 4 , Figure 4 This is a simplified structural diagram of a brightness compensation device for a display panel according to an embodiment of the present disclosure. In this embodiment, a brightness compensation device for a display panel is provided, which is used to perform the brightness compensation method for the display panel provided in the above embodiment. The brightness compensation device includes a region division module 31, a target region determination module 32, a detection module 33, and a compensation module 34.

[0105] The region division module 31 is used to divide the display panel into M first regions R, and to divide at least a portion of the first regions R into N second regions Ri; where M and N are natural numbers greater than 1, specifically M and N are greater than 2. Specifically, the region division module 31 can divide the display panel into M first regions R based on the quadtree decomposition method of the split-merge theory, and then divide each first region R into N second regions Ri.

[0106] The target region determination module 32 is used to determine the target region among N second regions Ri using the quadtree decomposition method.

[0107] The detection module 33 is used to obtain the brightness value and / or grayscale value of the sub-pixels in the target area.

[0108] The compensation module 34 is used to obtain the brightness compensation value of the target area based on the brightness value and / or gray value and the preset gamma curve, and to perform brightness compensation on the target area based on the brightness compensation value.

[0109] Specifically, the compensation module 34 includes a gamma curve acquisition unit and a compensation unit. The gamma curve acquisition unit fits the brightness and / or grayscale values ​​of the target area to obtain the actual gamma curve of the target area. The compensation unit compares the actual gamma curve with a preset gamma curve to obtain a brightness compensation value, and then performs brightness compensation on the target area based on the brightness compensation value. Specifically, the compensation unit can obtain the target brightness value corresponding to each grayscale level according to the preset gamma curve. It compares the actual brightness and / or grayscale values ​​of the sub-pixels of the target area with the target brightness value to determine the brightness compensation value of the target area.

[0110] The specific method by which the Gamma curve acquisition unit obtains the actual Gamma curve based on the brightness value and / or gray value, and the specific method by which the compensation unit obtains the brightness compensation value based on the actual Gamma curve and the preset Gamma curve to perform brightness compensation, are the same or similar to existing related technologies and can achieve the same or similar technical effects. For details, please refer to the existing technologies, which will not be elaborated here.

[0111] The brightness compensation device for the display panel provided in this embodiment, by setting up a region division module 31, further divides at least a portion of the first regions R into N second regions Ri based on the checkerboard positioning of M first regions R, enabling more precise target region positioning. Then, the target region determination module 32 uses a quadtree decomposition method to determine the target region among the N second regions Ri; compared to directly determining the target region from the first region or the entire display panel, more precise target region positioning can be achieved. Subsequently, the detection module 33 obtains the brightness value and / or grayscale value of the sub-pixels of the target region; and based on the brightness value and / or grayscale value, obtains the brightness compensation value of the target region, and performs brightness compensation on the target region based on the brightness compensation value; thus, it can ensure the compensation effect for larger Mura areas, and also meet the accuracy requirements of fine Mura compensation, resulting in a better improvement effect; and it is convenient to compare the display effect before and after improvement.

[0112] In some embodiments, see Figure 5 , Figure 5 A simplified structural diagram of a brightness compensation device for a display panel provided in another embodiment of this disclosure; the target area determination module 32 specifically includes a detection unit 321, a gray level determination unit 322, and a target area determination unit 323.

[0113] The detection unit 321 is used to acquire the brightness value and / or grayscale value of each sub-pixel in at least a portion of the second region Ri.

[0114] The gray level determination unit 322 is used to determine the gray level of the second region Ri based on the brightness value and / or gray value of the sub-pixels of the second region Ri.

[0115] In some specific embodiments, the grayscale level determination unit 322 is specifically used to obtain a first mean of the grayscale values ​​of all sub-pixels in the second region Ri based on the grayscale value of each sub-pixel in the second region Ri; and to obtain a second mean and a first variance of the grayscale values ​​of the first region R based on the first mean of the grayscale values ​​of each second region Ri; and then to determine the grayscale level of the second region Ri based on the grayscale value, the second mean, and the first variance of each sub-pixel in the second region Ri. See the above description for details.

[0116] In other specific embodiments, the grayscale level determination unit 322 is specifically used to obtain a third mean value of the brightness values ​​of all sub-pixels in the second region Ri based on the brightness value of each sub-pixel in the second region Ri; and to obtain a fourth mean value and a second variance of the brightness values ​​of the first region R based on the third mean value of the brightness values ​​of each second region Ri; and then to determine the grayscale level of the second region Ri based on the brightness value, the fourth mean value, and the second variance of each sub-pixel in the second region Ri. See the above description for details.

[0117] The target region determination unit 323 is configured to, in response to the second region Ri having a preset grayscale level and the current number of splits being less than a threshold, split the second region Ri into multiple sub-regions and increment the number of splits by one; use the sub-regions as new second regions Ri, and return to the detection unit 321 to obtain the brightness value and / or grayscale value of each sub-pixel in at least a portion of the second region Ri; in response to the second region Ri having a preset grayscale level and the current number of splits being equal to the threshold, determine the second region Ri as a target region. The target region determination unit 323 is also configured to, in response to the second region Ri having a grayscale level that is not a preset level, determine that the second region Ri is not a target region.

[0118] The brightness compensation device for the display panel provided in this embodiment, compared with the brightness compensation device provided in the above embodiment, further sets a target area determination module 32 to determine whether each second area Ri is a target area with a display Mura problem. Compared with the scheme of directly determining whether the first area R or the entire display panel has a display Mura problem, it can more accurately locate the Mura area of ​​the display panel, which is convenient for subsequent comparison of the display effect before and after brightness compensation improvement, and improves the uniformity of the overall display effect of the display panel. At the same time, it simplifies the compensation process and improves the compensation efficiency.

[0119] In the several embodiments provided in this disclosure, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces, indirect coupling or communication connection between apparatuses or units, and may be electrical, mechanical, or other forms.

[0120] Furthermore, the functional units in the various embodiments of this disclosure can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0121] The above are merely embodiments of this disclosure and do not limit the patent scope of this disclosure. Any equivalent structural or procedural changes made using the content of this disclosure and its drawings, or any direct or indirect application in other related technical fields, are similarly included within the patent protection scope of this disclosure.

Claims

1. A method for luminance compensation of a display panel, characterized in that, The display panel is divided into M first regions, and at least part of the first regions is divided into N second regions; wherein M and N are natural numbers greater than 1; A target region in the N second regions is determined by using a quadtree decomposition method; The brightness value and / or the grayscale value of a sub-pixel in the target region are obtained; Based on the brightness value and / or the grayscale value and a preset gamma curve, a brightness compensation value of the target region is obtained, and the target region is compensated for brightness based on the brightness compensation value; The step of determining the target region in the N second regions by using the quadtree decomposition method comprises: The brightness value and / or the grayscale value of each sub-pixel in at least part of the second regions are obtained; Based on the brightness value and / or the grayscale value of each sub-pixel in the second region, the grayscale level of the second region is determined; In response to the grayscale level of the second region being a preset level and the current splitting number being less than a number threshold, the second region is split into a plurality of sub-regions, and the splitting number is increased by one; the sub-regions are taken as new second regions, and the step of obtaining the brightness value and / or the grayscale value of each sub-pixel in at least part of the second regions is executed again; In response to the grayscale level of the second region being the preset level and the current splitting number being equal to the number threshold, the second region is determined as the target region; In response to the grayscale level of the second region not being the preset level, the second region is determined as a non-target region; then the non-target region does not need to be continuously split, and the non-target region does not need to be compensated for brightness; The step of determining the grayscale level of the second region based on the brightness value and / or the grayscale value of each sub-pixel in the second region comprises: Based on the grayscale value of each sub-pixel in the second region, a first mean value of the grayscale values of all sub-pixels in the second region is obtained; and based on the first mean value of the grayscale value of each second region, a second mean value and a first variance of the grayscale value of the first region are obtained; Based on the grayscale value of each sub-pixel in the second region, the second mean value, and the first variance, the grayscale level of the second region is determined; The step of determining the grayscale level of the second region based on the grayscale value of each sub-pixel in the second region, the second mean value, and the first variance comprises: An absolute value of a first difference value between the grayscale value of each sub-pixel in the second region and the second mean value of the first region is obtained; A ratio of the number of sub-pixels whose absolute value of the first difference value is greater than W times the first variance to the number of all sub-pixels in the second region is calculated; wherein W is a positive number; In response to the ratio being greater than or equal to a first threshold, the grayscale level of the second region is determined as the preset level; In response to the ratio being less than the first threshold, the grayscale level of the second region is determined as a non-preset level, and the second region is determined as a non-target region. The value of W is the same as the value of N.

2. The method of claim 1, wherein, W is 1, 1.5, 2, or 3.

3. The method of claim 1, wherein, The first threshold is 40%, 60%, 70%, or 80%.

4. The method of claim 1, wherein, ​ 5. The method of claim 1, wherein the step of obtaining the luminance compensation value of the target region based on the luminance value and / or the grayscale value and the preset gamma curve comprises: fitting the grayscale value of the target region to obtain an actual gamma curve of the target region; and comparing the actual gamma curve with the preset gamma curve to obtain the luminance compensation value. The method comprises:

6. A method for brightness compensation of a display panel, characterized by, dividing the display panel into M first regions, and dividing at least part of the first regions into N second regions; wherein M and N are natural numbers greater than 1; determining a target region in the N second regions by using a quadtree decomposition method; obtaining a luminance value and / or a grayscale value of a sub-pixel of the target region; obtaining a luminance compensation value of the target region based on the luminance value and / or the grayscale value and a preset gamma curve, and performing luminance compensation on the target region based on the luminance compensation value; The step of determining the target region in the N second regions by using the quadtree decomposition method comprises: obtaining a luminance value and / or a grayscale value of each sub-pixel in at least part of the second regions; determining a grayscale level of the second region based on the luminance value and / or the grayscale value of each sub-pixel in the second region; in response to the grayscale level of the second region being a preset level and a current splitting number being less than a number threshold, splitting the second region into a plurality of sub-regions, and increasing the splitting number by one; taking the sub-regions as new second regions, and returning to execute the step of obtaining the luminance value and / or the grayscale value of each sub-pixel in at least part of the second regions; in response to the grayscale level of the second region being the preset level and the current splitting number being equal to the number threshold, determining the second region as the target region; in response to the grayscale level of the second region not being the preset level, determining the second region as a non-target region; then without the need to continue splitting the non-target region, and without the need to perform luminance compensation on the non-target region; The step of determining the grayscale level of the second region based on the luminance value and / or the grayscale value of each sub-pixel in the second region comprises: obtaining a third mean value of the luminance values of all sub-pixels of the second region based on the luminance value of each sub-pixel in the second region; and obtaining a fourth mean value and a second variance of the luminance values of the first region based on the third mean value of the luminance values of each second region; determining the grayscale level of the second region based on the luminance value of each sub-pixel in the second region, the fourth mean value, and the second variance; The step of determining the grayscale level of the second region based on the luminance value of each sub-pixel in the second region, the fourth mean value, and the second variance comprises: obtaining an absolute value of a second difference value between the luminance value of each sub-pixel in the second region and the fourth mean value of the first region; and ​ a ratio of a number of sub-pixels whose absolute value of the second difference is greater than W times the second variance to a number of all sub-pixels in the second region, wherein W is a positive number; in response to the ratio being greater than or equal to a first threshold, determining that a gray level of the second region is a preset level; in response to the ratio being less than the first threshold, determining that the gray level of the second region is a non-preset level, and determining that the second region is a non-target region.

7. The method of claim 6, wherein, The value of W is the same as the value of N.

8. The method of claim 6, wherein, W is 1, 1.5, 2, or 3.

9. The method of claim 6, wherein, The first threshold is 40%, 60%, 70%, or 80%.

10. The method of claim 6, wherein the step of obtaining the brightness compensation value of the target region based on the brightness value and / or the gray value and a preset gamma curve comprises: fitting the brightness value of the target region to obtain an actual gamma curve of the target region; comparing the actual gamma curve with the preset gamma curve to obtain the brightness compensation value.

11. A luminance compensation device of a display panel, characterized by comprising: The method comprises: a region division module, configured to divide a display panel into M first regions, and divide at least part of the first regions into N second regions, wherein M and N are natural numbers greater than 1; a target region determination module, configured to determine a target region in the N second regions by using a quadtree decomposition method; a detection module, configured to obtain a brightness value and / or a gray value of a sub-pixel of the target region; a compensation module, configured to obtain a brightness compensation value of the target region based on the brightness value and / or the gray value and a preset gamma curve, and perform brightness compensation on the target region based on the brightness compensation value; the target region determination module comprises: a detection unit, configured to obtain a brightness value and / or a gray value of each sub-pixel in at least part of the second regions; a gray level determination unit, configured to determine a gray level of the second region based on the brightness value and / or the gray value of each sub-pixel in the second region; wherein the gray level determination unit is further configured to obtain a first mean value of the gray values of all sub-pixels in the second region based on the gray value of each sub-pixel in the second region, obtain a second mean value of the gray values of the first regions and a first variance based on the first mean value of the gray values of each of the second regions, obtain an absolute value of a first difference between the gray value of each sub-pixel in the second region and the second mean value of the first region, calculate a ratio of a number of sub-pixels whose absolute value of the first difference is greater than W times the first variance to a number of all sub-pixels in the second region, wherein W is a positive number, in response to the ratio being greater than or equal to a first threshold, determine that the gray level of the second region is a preset level, and in response to the ratio being less than the first threshold, determine that the gray level of the second region is a non-preset level. The gray scale determination unit is further configured to obtain a third mean value of the luminance values of all the sub-pixels in the second region based on the luminance value of each sub-pixel in the second region, obtain a fourth mean value of the luminance values of the first region and a second variance based on the third mean value of the luminance values of each second region, obtain a second difference value of the absolute value of the luminance value of each sub-pixel in the second region and the fourth mean value of the first region, calculate a ratio of the number of sub-pixels in the second region whose second difference value is greater than W times the second variance to the number of all sub-pixels in the second region, wherein W is a positive number, determine that the gray scale of the second region is a preset gray scale in response to the ratio being greater than or equal to a first threshold, and determine that the gray scale of the second region is a non-preset gray scale in response to the ratio being less than the first threshold; The target region determination unit is configured to split the second region into a plurality of sub-regions in response to the gray scale of the second region being the preset gray scale and the current splitting number being less than a number threshold, take the sub-regions as new second regions, and return to obtain the luminance value and / or the gray scale value of each sub-pixel in at least part of the second regions by using the detection unit, and increase the splitting number by one; determine the second region as a target region in response to the gray scale of the second region being the preset gray scale and the current splitting number being equal to the number threshold; determine the second region as a non-target region in response to the gray scale of the second region not being the preset gray scale, and do not need to continue to split the non-target region and do not need to perform luminance compensation on the non-target region.

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