Control system and control method of display module

Abstract

The invention discloses a control system and a control method of a display module, the display module comprises a direct type backlight module and a display panel, the direct type backlight module comprises a plurality of light-emitting elements, the display panel comprises a plurality of subareas, and each subarea corresponds to one light-emitting element; the control method comprises the following steps: acquiring a reference brightness image of the display panel, and fitting the reference brightness image to obtain an iterative convolution kernel, the reference brightness image being an image when a single partition of the display panel is lightened; obtaining an initial brightness image of the display panel, wherein the initial brightness image is an image when all partitions of the display panel are lightened; calculating target brightness according to the initial brightness image; generating an initial brightness compensation image; according to the iterative convolution kernel and the target brightness, performing multiple iterations on the initial brightness image and the initial brightness compensation image to obtain a brightness compensation table; and adjusting the light emitting brightness of each light emitting element of the backlight module according to the brightness compensation table.

Description

Technical Field

[0001] The present application relates to the field of semiconductor technology, and particularly relates to a control system and a control method for a display module. Background Art

[0002] A display module includes a backlight module and a display panel. The backlight module generally includes a side-entry backlight module and a direct-lit backlight module.

[0003] Figure 1a Fig. shows a schematic structural diagram of a display module including a side-entry backlight module. As Figure 1a shown, the display module 10 includes a side-entry backlight module 110 and a display panel 120. The backlight module 110 includes a light-emitting element 111 and a light guide plate 112. Among them, the light guide plate 112 is disposed on the back side of the display panel 120, and the light-emitting element 111 is disposed on the side of the light guide plate 112. The light emitted by the light-emitting element 111 is coupled into the light guide plate 211 and propagates to the back of the display panel 120 through the light guide plate 112. Applying the side-entry backlight module 110 to a large-size display module is challenging and local dimming cannot be performed.

[0004] Figure 1b Fig. shows a schematic structural diagram of a display module including a direct-lit backlight module. As Figure 1b shown, the display module 10' includes a direct-lit backlight module 110' and a display panel 120'. The backlight module 110' includes a plurality of light-emitting elements 111' and a light guide plate 112'. The plurality of light-emitting elements 111' and the light guide plate 112' are both disposed on the backlight side of the display panel 120'.

[0005] Figure 1c Fig. shows Figure 1b a brightness schematic diagram of a display module including a direct-lit backlight module as shown. As Figure 1c shown, since there may be differences in brightness among different light-emitting elements 111', and the light-emitting elements 111' at the edge and the light-emitting elements 111' in the central region are irradiated differently by other light-emitting elements 111', it will cause differences in the brightness of the display panel 120', thereby affecting the overall brightness uniformity of the display panel 120'. Summary of the Invention

[0006] In view of the above problems, the purpose of the present application is to provide a control system and a control method for a display module, which generate a brightness compensation table to compensate the light-emitting brightness of each partition of the display panel, so as to improve the brightness uniformity of the display panel.

[0007] According to one aspect of the present application, a control method for a display module is provided. The display module includes a direct-lit backlight module and a display panel. The direct-lit backlight module includes a plurality of light-emitting elements, and the display panel includes a plurality of partitions, each partition corresponding to one light-emitting element. The control method includes: obtaining a reference brightness image of the display panel and fitting the reference brightness image to obtain an iterative convolution kernel, where the reference brightness image is an image when a single partition of the display panel is lit; obtaining an initial brightness image of the display panel, where the initial brightness image is an image when all partitions of the display panel are lit; calculating a target brightness according to the initial brightness image; generating an initial brightness compensation image; performing multiple iterations on the initial brightness image and the initial brightness compensation image according to the iterative convolution kernel and the target brightness to obtain a brightness compensation table; and adjusting the light-emitting brightness of each light-emitting element of the backlight module according to the brightness compensation table.

[0008] Optionally, the method for obtaining the iterative convolution kernel includes: obtaining the brightness information of the row / column where the brightest point in the reference brightness image is located; adaptively searching for the row / column where the brightest point in the reference brightness image is located with a specified signal length, and intercepting a section with the largest sum of brightness within the specified signal length for Gaussian filtering, and fitting with a mixture Gaussian model to obtain a brightness curve; and obtaining a discrete iterative convolution kernel through the fitted function.

[0009] Optionally, the method for calculating the target brightness according to the initial brightness image includes: obtaining the maximum brightness value and the minimum brightness value of the initial brightness image, calculating an actual adjustment ratio according to the maximum brightness value and the minimum brightness value of the initial brightness image; generating a given adjustment ratio; selecting the smaller one between the actual adjustment ratio and the given adjustment ratio as the final adjustment ratio; and calculating the target brightness according to the final adjustment ratio.

[0010] Optionally, the calculation method of the actual adjustment ratio is: real_scale=(max - min) / (max + min), where max is the maximum brightness value of the initial brightness image, min is the minimum brightness value of the initial brightness image, and real_scale is the actual adjustment ratio; the calculation method of the target brightness is: obj = max*(1 - scale), where obj is the target brightness, max is the maximum brightness value of the initial brightness image, and scale is the final adjustment ratio.

[0011] Optionally, the method for obtaining the brightness compensation table includes: partitioning the initial brightness image to obtain the brightness of each partition; generating an initial brightness compensation image; performing multiple iterations on the initial brightness image and the initial brightness compensation image according to the iterative convolution kernel of the iteration and the target brightness to obtain a more accurate brightness compensation image; dividing the brightness compensation image after multiple iterations by the initial brightness image to obtain the brightness compensation table.

[0012] Optionally, the size of the initial brightness compensation image is the same as that of the initial brightness image, the partitions of the initial brightness compensation image correspond to the partitions of the initial brightness image, and the brightness of each partition of the initial brightness compensation image is zero.

[0013] Optionally, one iteration process includes: multiplying the initial brightness compensation image by the iterative convolution kernel of the iteration to obtain a brightness compensation result, and adding the brightness compensation result to the initial brightness image to obtain an updated image; calculating the difference between the brightness of each partition in the updated image and the target brightness, and adding the difference to the initial brightness compensation image to update the brightness compensation image; wherein, the updated image of each iteration is used as the initial brightness image of the next iteration process, and the updated brightness compensation image of each iteration is used as the initial brightness compensation image of the next iteration process.

[0014] Optionally, the ratio of the brightness compensation table to the maximum brightness value in the brightness compensation table is used as the final brightness compensation table.

[0015] According to another aspect of the present application, a control system for a display module is provided. The display module includes a direct-lit backlight module and a display panel. The direct-lit backlight module includes a plurality of light-emitting elements that directly irradiate the display panel, and the display panel includes a plurality of partitions, each partition corresponding to one light-emitting element; the control system includes: a brightness compensation module and a control module. The brightness compensation module performs the following steps to obtain a brightness compensation table: obtaining a reference brightness image of the display panel and fitting the reference brightness image to obtain an iterative convolution kernel, the reference brightness image being an image when a single partition of the display panel is lit; obtaining an initial brightness image of the display panel, the initial brightness image being an image when all partitions of the display panel are lit; calculating a target brightness according to the initial brightness image; generating an initial brightness compensation image; performing multiple iterations on the initial brightness image and the initial brightness compensation image according to the iterative convolution kernel and the target brightness to obtain a brightness compensation table; the control module adjusts the light-emitting brightness of each light-emitting element of the backlight module according to the brightness compensation table.

[0016] Optionally, the brightness compensation module performs the following steps to obtain an iterative convolution kernel: obtain the brightness information of the row / column where the point with the maximum brightness in the reference brightness image is located; adaptively search for the row / column where the point with the maximum brightness in the brightness reference image is located with a specified signal length, and intercept a section with the maximum sum of brightness within the specified signal length for Gaussian filtering, and fit it with a mixture Gaussian model to obtain a brightness curve; and obtain a discrete iterative convolution kernel through the fitted function.

[0017] Optionally, the brightness compensation module performs the following steps to obtain the target brightness: obtain the maximum brightness value and the minimum brightness value of the initial brightness image, calculate the actual adjustment ratio according to the maximum brightness value and the minimum brightness value of the initial brightness image; generate a given adjustment ratio; select the smaller value between the actual adjustment ratio and the given adjustment ratio as the final adjustment ratio; calculate the target brightness according to the final adjustment ratio.

[0018] Optionally, the calculation method of the actual adjustment ratio is: real_scale = (max - min) / (max + min); where max is the maximum brightness value of the initial brightness image, min is the minimum brightness value of the initial brightness image, and real_scale is the actual adjustment ratio; the calculation method of the target brightness is: obj = max*(1 - scale); where obj is the target brightness, max is the maximum brightness value of the initial brightness image, and scale is the final adjustment ratio.

[0019] Optionally, the brightness compensation module performs the following steps to obtain a brightness compensation table: partition the initial brightness image to obtain the brightness of each partition; generate an initial brightness compensation image; perform multiple iterations on the initial brightness image and the initial brightness compensation image according to the iterative convolution kernel and the target brightness to obtain a more accurate brightness compensation image; divide the brightness compensation image after multiple iterations by the initial brightness image to obtain the brightness compensation table.

[0020] Optionally, the size of the initial brightness compensation image is the same as that of the initial brightness image, the partition of the initial brightness compensation image corresponds to the partition of the initial brightness image, and the brightness of each partition of the initial brightness compensation image is zero.

[0021] Optionally, the brightness compensation module performs the following steps to complete one iteration process: multiplying the initial brightness compensation image by the iterative convolution kernel of the iteration to obtain a brightness compensation result, and superimposing the brightness compensation result on the initial brightness image to obtain an updated image; calculating the difference between the brightness of each partition in the updated image and the target brightness, and superimposing the difference on the initial brightness compensation image to update the brightness compensation image; wherein, the updated image of each iteration is used as the initial brightness image of the next iteration process, and the updated brightness compensation image of each iteration is used as the initial brightness compensation image of the next iteration process.

[0022] Optionally, the ratio of the brightness compensation table to the maximum brightness in the brightness compensation table is used as the final brightness compensation table.

[0023] The control system and control method of the display module provided by the present application generate a brightness compensation table to adjust the brightness of each partition of the display panel, thereby significantly improving the brightness uniformity of the display panel.

[0024] The control system and control method of the display module provided by the present application obtain a reference brightness image, fit the reference brightness image to obtain its light type curve, and simulate the brightness result after compensation according to the light type curve.

[0025] The control system and control method of the display module provided by the present application obtain a reference brightness image and an initial brightness image, and perform multiple iterations of the algorithm using the offline image to obtain an accurate brightness compensation table.

[0026] In a preferred embodiment, an actual adjustment ratio is calculated according to the maximum brightness and the minimum brightness of the initial brightness image, and compared with the given adjustment ratio. When the actual adjustment ratio is less than the given adjustment ratio, the actual adjustment ratio is selected as the final adjustment ratio, ensuring the accuracy of the brightness adjustment. When the actual adjustment ratio is greater than the given adjustment ratio, the given adjustment ratio is selected as the final adjustment ratio, and there will be no problem of over-adjustment. Description of the Drawings

[0027] Through the following description of the embodiments of the present application with reference to the drawings, the above and other objects, features and advantages of the present application will become clearer. In the drawings:

[0028] Figure 1a A schematic structural diagram of a display module including a side-in type backlight module is shown;

[0029] Figure 1b A schematic structural diagram of a display module including a direct-lit type backlight module is shown;

[0030] Figure 1c Is shown Figure 1bSchematic diagram of the brightness of a display module including a direct - type backlight module;

[0031] Figure 2 Schematic diagram showing the control system of the display module according to an embodiment of the present application;

[0032] Figure 3 Schematic diagram showing the structure of the display panel according to an embodiment of the present application;

[0033] Figure 4 Flowchart showing the brightness compensation method of the display module according to an embodiment of the present application;

[0034] Figure 5 Flowchart showing the method of obtaining an iterative convolution kernel based on a reference brightness image;

[0035] Figure 6a Schematic diagram showing a reference brightness image in an embodiment;

[0036] Figure 6b Optical curve obtained by fitting a reference brightness image in an embodiment;

[0037] Figure 7 Flowchart showing the method of obtaining a brightness target;

[0038] Figure 8 Flowchart of logical operation for obtaining a brightness target;

[0039] Figure 9 Flowchart of the method for obtaining a brightness compensation table;

[0040] Figure 10 Schematic diagram showing each iteration process. Detailed implementation manners

[0041] The present application will be described in more detail with reference to the accompanying drawings. In each drawing, like elements are denoted by like reference numerals. For clarity, the various parts in the drawings are not drawn to scale. In addition, some well - known parts may not be shown.

[0042] The present application can be presented in various forms, and some examples will be described below.

[0043] Figure 2 Schematic diagram showing the control system of the display module according to an embodiment of the present application; As Figure 2 shown, the display module 20 includes a direct - type backlight module 210 and a display panel 220. The backlight module 210 includes a plurality of light - emitting elements 211 and a light guide plate 212. The plurality of light - emitting elements 211 and the light guide plate 212 are both disposed on the backlight side of the display panel 212, and the light emitted by the plurality of light - emitting elements 211 directly irradiates the display panel 212.

[0044] The control system 30 includes a control module 310, a backlight driving module 320, and a brightness compensation module 330. The control module 310 sends control instructions to the backlight driving module 320. The backlight driving module 320 receives the control instructions and controls the brightness of the light-emitting element 211 according to the control instructions. The brightness compensation module 330 obtains a reference brightness image and an initial brightness image of the display panel 220, and provides a brightness compensation table (demura_table) to the control module 310 according to the reference brightness image and the initial brightness image. The control module 310 adjusts the emission brightness of each light-emitting element 211 of the backlight module 210 according to the brightness compensation table (demura_table) to eliminate the brightness difference between different partitions of the display panel 220.

[0045] Figure 3 The structural schematic diagram of the display panel according to the embodiment of the present application is shown, as Figure 3 shown, the display panel 220 includes a plurality of partitions 220a, and each partition 220a corresponds to a light-emitting element 211 of the backlight module 210. Among them, each light-emitting element 211 among the plurality of light-emitting elements 211 can be individually controlled so that each partition 220a of the display panel 220 is individually lit.

[0046] Figure 4 The flowchart of the brightness compensation method of the display module according to the embodiment of the present application is shown. For example, the control system of the display module shown in Figure 2 is used to execute the brightness compensation method.

[0047] In step S100, the brightness compensation module 330 obtains a reference brightness image of the display panel 220 and fits the reference brightness image to obtain an iterative convolution kernel.

[0048] The reference brightness image is the brightness image of the display panel when a single partition of the display panel is lit. The brightness compensation module 330 sends a first request signal to the control module 310 so that the control module 310 controls a single light-emitting element 211 in the backlight module 210 to emit light, and further makes a single partition 220a of the display panel 220 be individually lit. Figure 6a The schematic diagram of the reference brightness image in an embodiment is shown.

[0049] Figure 5 The flowchart of the method for obtaining an iterative convolution kernel according to the reference brightness image is shown, as Figure 5 shown, the method for obtaining the iterative convolution kernel includes:

[0050] S110: Obtain the brightness information of the row / column where the brightest point is located in the reference brightness image, and normalize it to between [0-1].

[0051] S120: Adaptively search for the row / column where the brightest point is located in the brightness reference image according to the specified signal length, and intercept a section with the maximum sum of brightness within the specified signal length for Gaussian filtering, and fit it with a mixture Gaussian model to obtain the light pattern curve. Figure 6b Fig. shows the light pattern curve obtained by fitting the reference brightness image in an embodiment. Among them, when the control module 310 provides different pwm (Pulse Width Modulation) signals to the backlight driving module 320, the light pattern curves obtained by fitting the reference brightness image are approximately the same.

[0052] S130: Obtain a discrete iterative convolution kernel through the fitted function. In a specific embodiment, the size of the iterative convolution kernel is 11*11, and the sum of the iterative convolution kernel is 1.

[0053] In step S200, the brightness compensation module 330 obtains the initial brightness image of the display panel 220.

[0054] The initial brightness image is the brightness image of the display panel when all partitions of the display panel are lit. The brightness compensation module 330 sends a second request signal to the control module 310 so that the control module 310 controls all the light-emitting elements 211 in the backlight module 210 to emit light, and further makes all the partitions 220a of the display panel 220 be lit separately. To avoid brightness saturation in some partitions of the initial brightness image, in this embodiment, the brightness image of the medium brightness full-screen white field (the full-screen gray value is 255) is obtained.

[0055] In step S300, the target brightness is calculated according to the initial brightness image.

[0056] Figure 7 Fig. shows the flowchart of the method for obtaining the brightness target. Figure 8 Fig. shows the logical operation flowchart for obtaining the brightness target; as Figure 7 and Figure 8 shown, the method for obtaining the target brightness includes:

[0057] S310: Obtain the actual adjustment ratio according to the initial brightness image.

[0058] In this step, the maximum brightness (max) and the minimum brightness (min) of the initial brightness image are obtained, and the actual adjustment ratio (real_scale) is calculated according to the maximum brightness and the minimum brightness. The calculation method of the actual adjustment ratio (real_scale) is:

[0059] real_scale = (max - min) / (max + min)

[0060] S320: Generate a given adjustment ratio, and calculate the final adjustment ratio based on the actual adjustment ratio and the given adjustment ratio.

[0061] In this embodiment, a given adjustment ratio (given_scale) is generated to prevent the actual adjustment ratio from being too large. Specifically, the smaller value between the actual adjustment ratio and the given adjustment ratio (given_scale) is selected as the final adjustment ratio (scale). The final adjustment ratio (scale) is:

[0062] scale = min(real_scale, given_scale)

[0063] S330: Calculate the target brightness (obj) according to the final adjustment ratio. The calculation method of the target brightness (obj) is:

[0064] obj = max * (1 - scale)

[0065] As described above, there are differences in the brightness of different regions of the display panel, and thus there are differences in the brightness of different regions of the obtained initial brightness image. Usually, the system gives a fixed given adjustment ratio (given_scale), and adjusts the initial brightness image with this given adjustment ratio (given_scale). However, when using a fixed given adjustment ratio (given_scale), there are usually problems such as low adjustment accuracy and over-adjustment. In this embodiment, an actual adjustment ratio (real_scale) is calculated based on the maximum brightness value and the minimum brightness value of the initial brightness image, and compared with the given adjustment ratio (given_scale). When the actual adjustment ratio (real_scale) is less than the given adjustment ratio (given_scale), the actual adjustment ratio (real_scale) is selected as the final adjustment ratio (scale), ensuring the accuracy of brightness adjustment. When the actual adjustment ratio (real_scale) is greater than the given adjustment ratio (given_scale), the given adjustment ratio (given_scale) is selected as the final adjustment ratio (scale), and the problem of over-adjustment will not occur.

[0066] In step S400, an initial brightness compensation image is generated.

[0067] Since there are differences in the brightness of each partition in the initial brightness image, the brightness compensation values for each partition are also different. To achieve targeted brightness compensation for each partition of the initial image, in this embodiment, the size of the initial brightness compensation image is the same as that of the initial brightness image, and the partitions of the initial brightness compensation image table correspond to the partitions of the initial brightness image. The brightness of each partition of the initial brightness compensation image is set to zero.

[0068] In step S500, based on the iterative convolution kernel and the target brightness, the initial brightness image and the initial brightness compensation image are iterated multiple times to obtain a brightness compensation table (demura_table).

[0069] Figure 9 The flowchart of the method for obtaining the brightness compensation table (demura_table) is shown, as Figure 9 shown, the method for obtaining the brightness compensation table (demura_table) includes:

[0070] In step S510, the initial brightness image is normalized, and the initial brightness image is partitioned to obtain the brightness of each partition.

[0071] In a specific embodiment, the initial brightness image is normalized to between [0 - 1]. The display panel 220 includes multiple partitions, and the initial brightness image can be correspondingly divided into multiple regions, that is, the number of partitions of the initial brightness image is equal to the number of partitions of the display panel 220. Further, the average brightness of each partition is the brightness of that partition. In other embodiments, the brightness mean of the central region of each partition can also be selected as the brightness of that partition.

[0072] In step S520, based on the iterative convolution kernel and the target brightness, the initial brightness image and the initial brightness compensation image are iterated multiple times to obtain a more accurate brightness compensation image.

[0073] Figure 10 The schematic diagram of each iteration process is shown, as Figure 10 shown, the process of each iteration includes:

[0074] S521: Multiply the initial brightness compensation image by the iterative convolution kernel of the iteration to obtain a brightness compensation result, and superimpose the brightness compensation result on the initial brightness image to obtain an updated image.

[0075] S522: Calculate the difference between the brightness of each partition in the updated image and the target brightness, and superimpose the difference on the initial brightness compensation image to update the brightness compensation image.

[0076] In this embodiment, steps S521 and S522 are repeatedly executed multiple times, and a more accurate brightness compensation image is obtained after multiple iterations. Among them, the updated image of each iteration is used as the initial brightness image for the next iteration process, and the brightness compensation image updated each time is used as the initial brightness compensation table for the next iteration process.

[0077] In step S530, a brightness compensation table (demura_table) is obtained.

[0078] Divide the brightness compensation image after multiple iterations by the initial brightness image to obtain the brightness compensation table (demura_table), that is, the brightness compensation table (demura_table) is the ratio of the brightness compensation image after multiple iterations to the initial brightness image. In this embodiment, an upper limit is set for the brightness compensation table (demura_table) to prevent situations that affect the visual perception such as color temperature deviation.

[0079] In other embodiments, in order to prevent intensity saturation, the ratio of the brightness compensation table (demura_table) to the maximum brightness value in the brightness compensation table (demura_table) is used as the final brightness compensation table (demura_table), that is, the final brightness compensation table (demura_table) is: demura_table / max(demura_table).

[0080] S600: The control module 310 compensates any display brightness of the display panel 220 with the brightness compensation table (demura_table) to improve the uniformity of the display panel brightness.

[0081] The control system and control method of the display module provided by this application generate a brightness compensation table to adjust the brightness of each partition of the display panel, thereby significantly improving the brightness uniformity of the display panel.

[0082] The control system and control method of the display module provided by this application obtain a reference brightness image, fit the reference brightness image to obtain its light type curve, and simulate the brightness result after compensation according to the light type curve.

[0083] The control system and control method of the display module provided by this application obtain a reference brightness image and an initial brightness image, and perform multiple iterations algorithmically using the offline image to obtain an accurate brightness compensation table.

[0084] In a preferred embodiment, an actual adjustment ratio is calculated based on the maximum brightness value and the minimum brightness value of the initial brightness image, and compared with the given adjustment ratio. When the actual adjustment ratio is less than the given adjustment ratio, the actual adjustment ratio is selected as the final adjustment ratio, ensuring the accuracy of brightness adjustment. When the actual adjustment ratio is greater than the given adjustment ratio, the given adjustment ratio is selected as the final adjustment ratio, avoiding the problem of over-adjustment.

[0085] As described above, the embodiments in accordance with the present application do not describe all the details in detail, nor do they limit the application to the specific embodiments described. Obviously, many modifications and variations can be made based on the above description. These embodiments are selected and specifically described in this specification to better explain the principles and practical applications of the present application, so that those skilled in the art can make good use of the present application and its modifications based on the present application. The present application is only limited by the claims and their full scope and equivalents.

Claims

1. A control method for a display module, wherein the display module comprises a direct-type backlight module and a display panel, wherein the direct-type backlight module comprises a plurality of light-emitting elements, and the display panel comprises a plurality of partitions, each partition corresponding to a light-emitting element ； The control method comprises: Acquire a reference brightness image of the display panel, and fit the reference brightness image to obtain an iterative convolution kernel, wherein the reference brightness image is an image when a single partition of the display panel is lit; Acquire an initial brightness image of the display panel, where the initial brightness image is an image when all subareas of the display panel are lit; Calculating target brightness according to the initial brightness image; generating an initial brightness compensated image; According to the iterative convolution kernel and the target brightness, the initial brightness image and the initial brightness compensation image are iterated multiple times to obtain a brightness compensation table; The light emitting brightness of each light emitting element of the backlight module is adjusted according to the brightness compensation table.

2. The control method according to claim 1, in, Methods for obtaining iterative convolution kernels include: Obtain the brightness information of the row / column where the maximum brightness point in the reference brightness image is located; Adaptively searching the row / column where the brightness point of the brightness reference image is the largest with the specified signal length, and intercepting a section with the largest brightness within the specified signal length for Gaussian filtering, and fitting with a mixed Gaussian model to obtain a brightness curve; and The discrete iterative convolution kernel is obtained through the fitted function.

3. The control method according to claim 1, in, The method for calculating the target brightness according to the initial brightness image comprises: Obtain the maximum brightness value and the minimum brightness value of the initial brightness image, and calculate the actual adjustment ratio according to the maximum brightness value and the minimum brightness value of the initial brightness image; Generate a given adjustment ratio; The smaller one between the actual adjustment ratio and the given adjustment ratio is selected as the final adjustment ratio; Calculate the target brightness based on the final adjustment ratio.

4. The control method according to claim 3, in, The actual adjustment ratio is calculated as follows: real_scale=(max-min) / (max+min); Among them, max is the maximum brightness of the initial brightness image, min is the minimum brightness of the initial brightness image, and real_scale is the actual adjustment ratio; The target brightness is calculated as: obj = max*(1-scale); Among them, obj is the target brightness, max is the maximum brightness of the initial brightness image, and scale is the final adjustment ratio.

5. The control method according to claim 1, in, Methods for obtaining the brightness compensation table include: Partition the initial brightness image and obtain the brightness of each partition; According to the iterative convolution kernel and the target brightness, the initial brightness image and the initial brightness compensation image are iterated multiple times to obtain a more accurate brightness compensation image; The brightness compensation image after multiple iterations is divided by the initial brightness image to obtain a brightness compensation table.

6. The control method according to claim 5, in, The size of the initial brightness compensated image is the same as that of the initial brightness image, the partitions of the initial brightness compensated image correspond to the partitions of the initial brightness image, and the brightness of each partition of the initial brightness compensated image is zero.

7. The control method according to claim 5, in, An iteration process includes: The initial brightness compensation image is multiplied by the iterative convolution kernel to obtain a brightness compensation result, and the brightness compensation result is superimposed on the initial brightness image to obtain an updated image; Calculate the difference between the brightness of each partition in the updated image and the target brightness, add the difference to the initial brightness compensated image, and update the brightness compensated image; The image updated in each iteration is used as the initial brightness image of the next iteration process, and the brightness compensation image updated in each iteration is used as the initial brightness compensation image of the next iteration process.

8. The control method according to claim 5, in, The ratio of the brightness compensation table to the maximum brightness value in the brightness compensation table is used as the final brightness compensation table.

9. A control system for a display module, the display module comprising a direct-type backlight module and a display panel, the direct-type backlight module comprising a plurality of light-emitting elements directly irradiating the display panel, the display panel comprising a plurality of partitions, each partition corresponding to a light-emitting element ； The control system includes: a brightness compensation module and a control module. The brightness compensation module performs the following steps to obtain a brightness compensation table: Acquire a reference brightness image of the display panel, and fit the reference brightness image to obtain an iterative convolution kernel, wherein the reference brightness image is an image when a single partition of the display panel is lit; Acquire an initial brightness image of the display panel, where the initial brightness image is an image when all subareas of the display panel are lit; Calculating target brightness according to the initial brightness image; generating an initial brightness compensated image; According to the iterative convolution kernel and the target brightness, the initial brightness image and the initial brightness compensation image are iterated multiple times to obtain a brightness compensation table; The control module adjusts the light emitting brightness of each light emitting element of the backlight module according to the brightness compensation table.

10. The control system of the display module according to claim 9, in, The brightness compensation module performs the following steps to obtain an iterative convolution kernel: Obtain the brightness information of the row / column where the maximum brightness point in the reference brightness image is located; Adaptively search the row / column where the brightness point in the brightness reference image is the maximum with the specified signal length, and intercept the section with the maximum brightness within the specified signal length for Gaussian filtering, and fit it with a mixed Gaussian model to obtain a brightness curve; as well as The discrete iterative convolution kernel is obtained through the fitted function.

11. The control system of the display module according to claim 9, in, The brightness compensation module performs the following steps to obtain the target brightness: Obtain the maximum brightness value and the minimum brightness value of the initial brightness image, and calculate the actual adjustment ratio according to the maximum brightness value and the minimum brightness value of the initial brightness image; Generate a given adjustment ratio; The smaller one between the actual adjustment ratio and the given adjustment ratio is selected as the final adjustment ratio; Calculate the target brightness based on the final adjustment ratio.

12. The control system of the display module according to claim 11, in, The actual adjustment ratio is calculated as follows: real_scale=(max-min) / (max+min); Among them, max is the maximum brightness of the initial brightness image, min is the minimum brightness of the initial brightness image, and real_scale is the actual adjustment ratio; The target brightness is calculated as: obj = max*(1-scale); Among them, obj is the target brightness, max is the maximum brightness of the initial brightness image, and scale is the final adjustment ratio.

13. The control system of the display module according to claim 9, in, The brightness compensation module performs the following steps to obtain a brightness compensation table: Partition the initial brightness image and obtain the brightness of each partition; generating an initial brightness compensated image; According to the iterative convolution kernel and the target brightness, the initial brightness image and the initial brightness compensation image are iterated multiple times to obtain a more accurate brightness compensation image; The brightness compensation image after multiple iterations is divided by the initial brightness image to obtain a brightness compensation table.

14. The control system of the display module according to claim 13, in, The size of the initial brightness compensated image is the same as that of the initial brightness image, the partitions of the initial brightness compensated image correspond to the partitions of the initial brightness image, and the brightness of each partition of the initial brightness compensated image is zero.

15. The control system of the display module according to claim 13, in, The brightness compensation module performs the following steps to complete an iterative process: The initial brightness compensation image is multiplied by the iterative convolution kernel to obtain a brightness compensation result, and the brightness compensation result is superimposed on the initial brightness image to obtain an updated image; Calculate the difference between the brightness of each partition in the updated image and the target brightness, add the difference to the initial brightness compensated image, and update the brightness compensated image; The updated image of each iteration is used as the initial brightness image of the next iteration process, and the brightness compensation image updated of each iteration is used as the initial brightness compensation image of the next iteration process.

16. The control system of the display module according to claim 13, in, The ratio of the brightness compensation table to the maximum brightness value in the brightness compensation table is used as the final brightness compensation table.

Images