WO2020124479A1

WO2020124479A1 - Brightness demura method and system for liquid crystal display module

Info

Publication number: WO2020124479A1
Application number: PCT/CN2018/122322
Authority: WO
Inventors: 黄建军; 刘世仁; 李桐; 黄敬雄
Original assignee: 深圳大学
Priority date: 2018-12-20
Filing date: 2018-12-20
Publication date: 2020-06-25

Abstract

A brightness demura method for a liquid crystal display module, comprising: configuring greyscale values of multiple input signals, and acquiring brightness values of the input signals displayed on a liquid crystal display module (S101); according to the greyscale values of the multiple input signals and corresponding brightness values, solving the coefficient of a greyscale-brightness segmentation conversion function by means of performing fitting (102); configuring greyscale values of various inputted grey levels to be corrected of the liquid crystal display module, and according to the gamma relationship, acquiring target brightness values outputted by the grey levels to be corrected (103); obtaining compensation data corresponding to various grey levels to be corrected according to the target brightness values, the greyscale-brightness segmentation conversion function and the grey levels to be corrected (104); and using the compensation data to modify brightness values outputted by the liquid crystal display module such that the brightness values outputted by the liquid crystal display module are the target brightness values (105), thereby removing mura of the liquid crystal display module; because the greyscale-brightness segmentation conversion function may more accurately express the relationship between the actual input greyscale and output brightness of a liquid crystal display module, the effect of removing mura of a liquid crystal display module by using the method is better than that of the existing technology.

Description

Demura method and system for brightness of liquid crystal display module

Technical field

The invention relates to the field of display technology, and in particular to a brightness Demura method and system of a liquid crystal display module.

Background technique

With the development of liquid crystal display technology, liquid crystal displays have been widely used in various fields of life. The liquid crystal display module is the main component of the liquid crystal display. During the production process, the liquid crystal display module has various display unevenness phenomena (Mura) due to materials, production processes and other reasons. The existing method to eliminate the display unevenness of the LCD module is the Demura method (method of eliminating the Mura), which reduces or even eliminates the brightness unevenness on the LCD module (Mura) through brightness compensation. The size of the group is becoming more and more obvious, and the existing Demura method is difficult to meet the requirements of quality and production efficiency.

The traditional LCD module brightness correction process is: first perform gamma correction on the LCD module, store the calculated gamma correction data in its Flash (ROM), and then perform brightness Demura on the LCD module Calculate the brightness compensation data, and finally store it in its Flash ROM. When the LCD module wants to display the image, its control circuit controls the display brightness according to the gray level value displayed by the current display requirements and finds the Flash ROM data through the table lookup method. To complete the display brightness correction.

For the brightness of the liquid crystal display module, the method adopted by the existing products is: first collect the brightness image of the liquid crystal display module, and then use a single form function to fit the relationship between the grayscale and brightness of the liquid crystal display module to calculate the brightness Compensation data, store the data in its Flash ROM, and finally control the LCD display module to display the brightness image. The LCD display module uses the current compensation data to correct the brightness display brightness.

The traditional brightness correction process uses gamma correction equipment to perform gamma correction on the liquid crystal display module, and then uses the brightness Demura equipment to eliminate the Mura of the display module. When the effect of gamma correction is not good, the gamma value will be too large or small, which affects the subsequent Demura process, resulting in poor Mura elimination effect, or the gamma value after the previous gamma correction meets the requirements, but the liquid crystal The display module changes the gamma value during the Demura process, resulting in the gamma value not meeting the requirements. Therefore, the gamma correction should be performed again.

The existing Demura method eliminates the poor effect of the liquid crystal display module Mura, resulting in unsatisfactory product quality. After Demura, gamma correction occurs again, which reduces the production efficiency. Therefore, the Mura elimination effect of the liquid crystal display module in the prior art is affected by the size of the gamma value and the gamma value caused by Demura does not meet the requirements, thereby reducing the quality and production efficiency of the display module product.

technical problem

The main object of the present invention is to provide a brightness Demura method and system for a liquid crystal display module, which are used to solve the technical problem of eliminating the poor effect of the liquid crystal display module Mura by the existing method.

Technical solution

To achieve the above objective, a first aspect of the present invention provides a brightness Demura method for a liquid crystal display module, the method including:

Set the gray value of multiple input signals to obtain the brightness value of the input signal displayed on the liquid crystal display module;

According to the gray values of the plurality of input signals and the corresponding brightness values, the coefficients of the gray-luminance segmented conversion function are solved by fitting, and the gray-luminance segmented conversion function represents the liquid crystal Display module brightness conversion relationship;

Setting the gray value of each gray level to be corrected of each input of the liquid crystal display module, and obtaining the target brightness value of the gray level to be corrected output according to the gamma relationship;

Obtaining compensation data corresponding to each gray level to be corrected according to the target brightness value, the gray-to-luminance segmentation conversion function, and the gray level to be corrected;

The compensation data is used to correct the brightness value output by the liquid crystal display module so that the brightness value output by the liquid crystal display module is the target brightness value.

A second aspect of the present invention provides a brightness Demura system of a liquid crystal display module. The system includes:

The first setting module is used to set the gray values of multiple input signals and respectively obtain the brightness values of the input signals displayed on the liquid crystal display module;

The solving module is used to solve the coefficients of the grayscale-luminance segmentation conversion function by fitting according to the grayscale values of the multiple input signals and the corresponding brightness values. The function represents the brightness conversion relationship of the liquid crystal display module;

A second setting module, configured to set the gray value of each gray level to be corrected of each input of the liquid crystal display module, and obtain the target brightness value of the gray level to be corrected output according to the gamma relationship;

A processing module, configured to obtain compensation data corresponding to each gray level to be corrected according to the target luminance value, the gray-to-luminance segmentation conversion function, and the gray level to be corrected;

The correction module is used for correcting the brightness value output by the liquid crystal display module using the compensation data, so that the brightness value output by the liquid crystal display module is the target brightness value.

Beneficial effect

In the above technical solution, the gray-to-luminance segmented conversion function can be used to more accurately represent the relationship between the gray value of the actual input signal of the liquid crystal display module and the output brightness value. According to the gray-to-luminance segmented conversion function The compensation data can be accurately calculated, thereby improving the elimination effect of eliminating the liquid crystal display module Mura, and the elimination effect is superior to the prior art. In this technical solution, the target brightness value of the grayscale output to be corrected is set according to the gamma relationship. The gamma value of the LCD module after Demura meets the requirements, and there is no need to perform gamma correction again, which improves the generation efficiency.

BRIEF DESCRIPTION

FIG. 1 is a schematic flowchart of a brightness Demura method of a liquid crystal display module according to an embodiment of the invention;

2 is a schematic flowchart of a Demura method for brightness of a liquid crystal display module according to another embodiment of the present invention;

Figure 3 is a relationship diagram between the LCD module and Gamma;

4 is a schematic structural diagram of a brightness Demura system of a liquid crystal display module according to another embodiment of the present invention;

5 is a schematic structural diagram of a brightness Demura system of a liquid crystal display module according to another embodiment of the present invention;

6 is a schematic structural diagram of a computing device according to another embodiment of the present invention.

Embodiments of the invention

In order to make the purpose, features, and advantages of the present invention more obvious and understandable, the technical solutions in the embodiments of the present invention will be described clearly and completely in conjunction with the drawings in the embodiments of the present invention. Obviously, the description The embodiments are only a part of the embodiments of the present invention, but not all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative efforts fall within the protection scope of the present invention.

Due to the technical problem of eliminating the poor effect of the liquid crystal display module Mura in the prior art. In order to solve the above technical problems, the present invention proposes a brightness Demura method of a liquid crystal display module.

Please refer to FIG. 1, which is a schematic flowchart of a brightness Demura method of a liquid crystal display module according to an embodiment of the present invention. The brightness Demura method of the liquid crystal display module specifically includes:

Step 101: Set the gray values of multiple input signals, and obtain the brightness values of the input signals displayed on the liquid crystal display module, respectively.

Specifically, the gray value of multiple signals is set, and the signal is input into the liquid crystal display module, the liquid crystal display module displays the signal, and the brightness value acquisition device is used to acquire the brightness value of the signal displayed by the liquid crystal display module. The brightness value displayed by the liquid crystal display module corresponds one-to-one to the gray value of multiple input signals.

Among them, the input signal is the input signal of all pixels, each pixel input signal corresponds to a signal component in each input signal, the gray value of the input signal is the specific gray value of the input signal, the gray value is the Known.

Step 102: According to the gray values of the multiple input signals and the corresponding brightness values, the coefficients of the gray-luminance segmented conversion function are solved by fitting, and the gray-luminance segmented conversion function represents the liquid crystal display module The relationship of the brightness conversion.

Specifically, the gray values and corresponding brightness values of multiple input signals are substituted into the gray-luminance segmented conversion function, and the coefficients of the gray-luminance segmented conversion function are calculated by a fitting method, where, The gray-to-luminance segmented conversion function is represented by a polynomial function at low gray levels and an exponential function at high gray levels. The gray-to-luminance segmented conversion function is

Among them, (x, y) is the two-dimensional coordinates of each input signal, a _k (x, y), b ₀ (x, y) and b ₁ (x, y) are coefficients, k = 0, 1, 2 ,...,K,G are the segmentation points of the grayscale-luminance segmentation conversion function, K is the order of the polynomial, g(x,y) is the grayscale value of the input signal, f(g(x ,y); x,y) is the output brightness value;

Among them, the resolution of the liquid crystal display module is n×m, the two-dimensional coordinates (x, y) of each input signal of the liquid crystal display module, the values of x are: 0, 1, ..., n-1, The values of y are 0, 1, ..., m-1, and the gray-to-luminance segmented conversion function represents the gray value g(x, y) of the input signal and the output luminance value f(g(x, y); x ,y), when the gray value of the input signal belongs to the middle and low gray levels, use the polynomial function located above in the gray-to-luminance segmentation conversion function to express g(x,y) and f(g( x,y); the relationship between x,y); when the gray value of the input signal belongs to the high gray level, use the exponential function located below in the gray-to-luminance segmented conversion function to express g(x,y) Relationship with f(g(x,y); x,y).

It needs to be said that in each LCD module, according to the gray value of the input signal and the corresponding brightness value, the coefficients of the gray-luminance segmented conversion function are solved by fitting, according to the LCD display The grayscale-luminance segmentation conversion function solved by the data of the module can more accurately represent the relationship between the grayscale value of the input signal of the liquid crystal display module and the output brightness value.

Step 103: Set the gray value of each gray level to be corrected of each input of the liquid crystal display module, and obtain the target brightness value of the gray level to be corrected output according to the gamma relationship.

Specifically, S grayscale values of the grayscales to be corrected are set, and according to the gamma relationship between the grayscale values of the grayscales to be corrected and the output target brightness values, the corresponding output target brightness values of the S grayscales to be corrected are obtained ;

The gamma relationship is:

Among them, D _i is the gray value of the i-th gray level to be corrected, L _i is the i-th target brightness value, i=1, 2, ..., S, and L _max is the maximum value displayed by the liquid crystal display module Brightness value, L _min is the minimum brightness value displayed by the liquid crystal display module, r is the gamma value of the liquid crystal display module, 0≤r≤24.

It should be noted that the gray level to be corrected is a gray value of the input signal, and gamma is a physical property of the liquid crystal display module. When the input signal and the output signal displayed by the liquid crystal display module conform to the Gamma curve, The display of the liquid crystal display module conforms to the visual characteristics of the human eye, which is comfortable when the human eye observes the display of the liquid crystal display module. That is, when the relationship curve between the gray value of the gray scale to be corrected and the output target brightness value of the liquid crystal display module satisfies the Gamma curve, the liquid crystal display module display conforms to the visual characteristics of the human eye, and the human eye is more comfortable when observing the display device display . The normal range of gamma value is (0, 2.7).

Step 104: Obtain compensation data corresponding to each gray level to be corrected according to the target brightness value, the gray-to-luminance segmentation conversion function formula, and the gray level to be corrected.

Among them, it is necessary to select the specific functional relationship in the gray-to-luminance segmentation conversion function according to the specific gray value of the gray level to be corrected to solve the compensation data corresponding to the gray level to be corrected, and the gray level to be corrected corresponds to the compensation data. Different compensation data can be calculated according to the gray values of different gray levels to be corrected. In addition, a compensation data table including a plurality of compensation data of gray levels to be corrected is stored in the liquid crystal display module.

Step 105: Use the compensation data to correct the brightness value output by the liquid crystal display module, so that the brightness value output by the liquid crystal display module is the target brightness value.

For the input signal of the liquid crystal display module, the compensation data corresponding to the gray value in the compensation data table can be searched according to the specific gray value of the input signal. Therefore, the brightness value output by the signal is corrected according to the compensation data, so that the brightness value output by the liquid crystal display module is the target brightness value. Corresponding to the input signal with the same gray value, the brightness value output by the signal is adjusted to the target brightness value, thereby eliminating the Mura phenomenon of the liquid crystal display module.

It can be seen from the above Demura method of the brightness of the liquid crystal display module, in this method, the output brightness value of the liquid crystal display module is corrected according to the compensation data, so that the output brightness value of the liquid crystal display module is the target brightness value, thereby eliminating the liquid crystal display mode Group Mura. In this method, the grayscale-luminance segmented conversion function represents the brightness conversion relationship of the liquid crystal display module, and the grayscale-luminance segmented conversion function coefficients are based on the grayscale values and output brightness values of multiple input signals of the liquid crystal display module Calculated, the gray-to-luminance segmented conversion function can more accurately represent the relationship between the gray value of the actual input signal of the liquid crystal display module and the output brightness value, and can be accurately calculated according to the gray-to-luminance segmented conversion function The compensation data comes out, thereby improving the elimination effect of eliminating the LCD display module Mura.

As shown in FIG. 2, FIG. 2 is a schematic flowchart of a Demura method for brightness of a liquid crystal display module according to another embodiment of the present invention. The method includes:

Step 201: Set the gray values of multiple input signals to obtain the brightness values of the input signals displayed on the liquid crystal display module, respectively.

Specifically, the gray value of N signals is set, and the N signals are input into the liquid crystal display module, the liquid crystal display module displays the signal, and the brightness value acquisition device is used to acquire the brightness value of the signal displayed by the liquid crystal display module , The N brightness values obtained correspond to the gray values of the N signals in one-to-one correspondence. The relationship of the gray values of the set N signals is as follows: 0≤g ₁ (x,y)<g ₂ (x,y)<...<g _N1 (x,y)<g _N1+1 (x ,y)<g _N1+2 (x,y)<...<g _N (x,y), where g _N1 (x,y)<G, g _N (x,y)≤G _max ,N -1≥N ₁ ≥K+1, input the above N signals to the liquid crystal display module in sequence, obtain the brightness value of the signal displayed by the liquid crystal display module in sequence, and obtain the corresponding N brightness values: f(g ₁ (x,y); x,y), f(g ₂ (x,y); x,y),...f(g _N1 (x,y); x,y), f(g _{N1+ 1} (x,y); x,y), f(g _N1+2 (x,y); x,y),...f(g _N (x,y); x,y).

Among them, for a commonly used 8-bit display, the gray value of the input signal ranges from 0 to 255, and the N values are related to the number of solving coefficients.

Step 202: According to the gray values of the multiple input signals and the corresponding brightness values, the coefficients of the gray-luminance segmented conversion function are solved by fitting, the gray-luminance segmented conversion function represents the liquid crystal display module The relationship of the brightness conversion.

Among them, the gray value of the N input signals and the corresponding brightness value are substituted into the gray-luminance segmented conversion function, and the coefficients of the gray-luminance segmented conversion function are calculated by the fitting method, gray- The brightness segmentation conversion function is as follows:

Specifically, the gray values g ₁ (x, y), g ₂ (x, y), ..., g _N1 (x, y) of the first N ₁ input signals and the corresponding output luminance value f (g ₁ (x, y); x, y), f(g ₂ (x, y); x, y),... f(g _N1 (x, y); x, y) is substituted into gray-luminance In the polynomial formula of the piecewise conversion function, the coefficient a _k (x,y) in the polynomial function is solved, and then g _N1+1 (x,y), g _N1+2 (x,y),..., g _N (x,y) and the corresponding f(g _N1+1 (x,y); x,y), f(g _N1+2 (x,y); x,y),...f(g _N (x, y); x, y) is substituted into the formula of the exponential function of the grayscale-luminance piecewise conversion function, and the coefficients b ₀ (x, y) and b of the formula of the exponential function are solved by the curve fitting method ₁ (x,y). When the coefficients of the grayscale-luminance segmented conversion function are solved, the grayscale-luminance segmented conversion function is solved, that is, the brightness conversion relation is solved.

Step 203: Set the gray values of the gray scales to be corrected input by the liquid crystal display module, and obtain the target brightness values of the gray scales to be corrected output according to the gamma relationship.

Specifically, the gray values of the S gray levels to be corrected are set to D ₁ , D ₂ , ... D _S , respectively, and the target brightness values of the S gray levels to be corrected to be solved according to the gamma relationship are: L ₁ , L ₂ ,...L _S.

Among them, the gamma relationship is as follows:

Step 204: Input the target brightness corresponding to the S gray scales to be corrected into the gray-to-luminance segmentation conversion function, and calculate the gray value of the input signals corresponding to the gray scales to be corrected, that is, to obtain the input signal The gray scale value is: g _i (x, y) = f ^-1 (L _i ; x, y), i = 1, 2, ..., S.

Specifically, if the gray value D ₁ of the gray level to be corrected is in the range of [0, G), the target luminance value L ₁ corresponding to the gray level D ₁ to be corrected is input to the polynomial of the gray-to-luminance piecewise conversion function In the formula, as follows:

According to the above formula, the gray value g(x,y) of the input signal whose output brightness is the target brightness is solved.

If the gray value D ₁ of the gray level to be corrected is within the range of [G, G _max ], the target luminance value L ₁ corresponding to the gray level D ₁ to be corrected is input to the exponential function relationship of the gray-to-luminance segmentation conversion function In the formula, as follows:

Step 205: Obtain compensation data for the gray level to be corrected according to the gray level to be corrected and the gray value of the corresponding input signal.

Specifically, based on the gray level to be corrected and the gray value of the corresponding input signal, the compensation data is calculated according to the compensation data generation formula, and the compensation data generation formula is:

ΔD _i (x,y)=g _i (x,y)-D _i (5)

Among them, D _i is the ith gray level to be corrected, the corresponding g _i (x, y) is the gray value of the input signal and ΔD _i (x, y) is the compensation data, i=1, 2,... , S.

The formula to be corrected gradation generating compensation data D ₁ ΔD ₁ (x, y), corresponding, according to the compensation formula data generation, generate gray scale to be corrected _{_{D 1, D 2, ... D}} S corresponding compensation Data ΔD ₁ (x,y), ΔD ₂ (x,y), ..., ΔD _S (x,y).

It should be noted that the compensation data table includes: a plurality of gray levels to be corrected and their corresponding compensation data, and the compensation data corresponding to the gray levels to be corrected can be obtained according to the gray values of the gray levels to be corrected. According to the hardware circuit of the liquid crystal display module, the compensation data table is stored in the flash ROM of the display device, so as to subsequently be used to correct the display brightness of the display device.

It should also be noted that step 204 and step 205 in this embodiment are the detailed steps of step 104 in the previous embodiment.

Step 206: Use the compensation data to correct the brightness value output by the liquid crystal display module, so that the brightness value output by the liquid crystal display module is the target brightness value.

Specifically, the correction amount is calculated based on the compensation data, and then the brightness value of the signal output is corrected based on the correction amount.

Among them, after the output signal brightness value of the input signal is corrected by the correction amount, the brightness value of the output signal is the corrected brightness, therefore, the naked eye can observe the image displayed by the liquid crystal display module with naked eyes, so that the naked eye can not see Mura. display effect.

In the embodiment of the present invention, the two-dimensional coordinates of each signal are set to (x, y), the values of x are 0, 1, ..., 3839, and the values of y are 0, 1, ..., 2519, G _max is the maximum value of the pixel gray scale is 255, 0≤g(x,y)≤255, the cut-off point G of the grayscale-luminance segmentation conversion function is set to 200, and the order K of the polynomial function is set to 4 . The gray scale-luminance segmentation conversion function of the LCD module representing the brightness conversion relationship is as follows:

Among them, a ₀ (x,y), a ₁ (x,y), a ₂ (x,y), a ₃ (x,y), a ₄ (x,y), b ₀ (x,y) and b ₁ (x,y) is the coefficient.

In the embodiment of the present invention, the number N of input signals is set to 6, and the gray values of the input signals are g ₁ (x, y) = 0, g ₂ (x, y) = 20, and g ₃ ( x, y) = 50, g ₄ (x, y) = 100, g ₅ (x, y) = 200, g ₆ (x, y) = 255 are sequentially input into the liquid crystal display module, and the 6 inputs are obtained The signals correspond to the six brightness values displayed in the LCD module are f(g ₁ (x, y); x, y), f(g ₂ (x, y); x, y), f(g ₃ (x,y); x,y), f(g ₄ (x,y); x,y), f(g ₅ (x,y); x,y), f(g ₆ (x,y) ; X, y). Since the cutoff point G of the grayscale-luminance segmentation conversion function is 200, enter 0, 20, 50, 100 and the corresponding display brightness value into the formula (a), and use the least squares curve fitting method to solve the formula (a) Coefficients a ₀ (x,y), a ₁ (x,y), a ₂ (x,y), a ₃ (x,y), a ₄ (x,y), and then use the curve fitting method to solve the formula The coefficients b ₀ (x, y) and b ₁ (x, y) in (b). Thus, the expression of the grayscale-luminance piecewise conversion function is solved.

In the embodiment of the present invention, after the expression of the gray-to-luminance piecewise conversion function is solved, the process of generating compensation data is specifically as follows: the value of the number S of gray levels to be corrected is set to 3, and three grays to be corrected The order is: D ₁ = 24, D ₂ = 65, D ₃ = 220, input the value of the gray level to be corrected into the gamma relationship (2), the Gamma value in (2) is 2.2, and get the corresponding The target brightness values are L ₁ , L ₂ , and L ₃ , respectively, where the gray value 24 of the gray level D ₁ to be corrected is in the range of [0, 200), and the target brightness value L corresponding to the gray level D ₁ to be corrected is ₁ Bring into formula (a), get the following formula:

The gray value g ₂₄ (x, y) of the input signal of the target luminance value L ₁ is solved by the Newton iteration method from the above formula, and the compensation data of the gray level 24 to be corrected is:

ΔD ₁ (x,y)=g ₂₄ (x,y)-24 (d)

Target brightness value L ₂ into the equation to be corrected grayscale gradation value D ₂ 65 is in the range [0,200), to be corrected gray level corresponding to D ₂ (a) to give the following formula:

The gray value g ₆₅ (x, y) of the input signal of the target luminance value L ₂ is solved by the Newton iteration method from the above formula, and the compensation data of the gray level 65 to be corrected is:

ΔD ₂ (x,y)=g ₆₅ (x,y)-65 (f)

D gray scale to be corrected gradation value ₃ in the range of 220 [200,255), D ₃ to be corrected gray scale value corresponding to the target luminance L ₃ into Equation (a) to give the following formula:

The gray value g ₂₀₀ (x, y) of the input signal of the target luminance value L ₃ is directly solved from the above formula, and the compensation data of the gray level 220 to be corrected is:

ΔD ₃ (x,y)=g ₂₂₀ (x,y)-220 (h)

Wherein, ΔD ₁ (x, y), ΔD ₂ (x, y), ΔD ₃ (x, y) are the compensation data corresponding to the gray level to be corrected 24, the gray level to be corrected 65 and the gray level to be corrected 220 respectively. The generated compensation data is converted into a data table in a corresponding format by the hardware circuit of the liquid crystal display module, and stored in the Flash ROM to correct the display brightness of the liquid crystal display module. According to the compensation data table, the brightness value of the output signal can be corrected to achieve the effect of eliminating the LCD display module Mura.

In the embodiment of the present invention, the gray value of the input signal of the liquid crystal display module is 100, and its display signal is collected by a camera. The display signal is a display image, and the displayed picture has bright twill, dark twill, and diagonal stripe Black belts, diagonal strips of white belts, vertical white belts, vertical black belts and black massive Mura, Mura area reached 95%. After adopting the method of the present invention to perform brightness Demura on the liquid crystal display module, the liquid crystal display module is allowed to display an image with a gray value of an arbitrary value. The naked eye observes the image, and the Mura phenomenon of the image is not observed.

As shown in FIG. 3, FIG. 3 is a relationship diagram between a liquid crystal display module and Gamma. FIG. 3 is a process of 500 LCD display modules processed by using the brightness of the LCD display module Demura method, and 20 of them are randomly measured. Gamma value. It should be noted that the National Television System Committee recommends a Gamma value of 2.2, and the general industry requires the Gamma value of the LCD module after Demura to be between 10 and 245 when the Gamma value is between 2.0 and 2.4. Table 1 is the result of processing 500 LCD modules by this method. The statistics in the table are the main types of Mura, corresponding severity and just identifiable threshold of 500 LCD modules before processing (Just noticeable difference) , JND), and Mura elimination after treatment. The JND value is used internationally to measure the Mura level. When the JND value is less than 1, the Mura elimination index meets the requirements.

Table 1

It should also be noted that the brightness Demura method of the liquid crystal display module can also be used for the brightness Demura of other display devices.

It can be seen from the Demura method of brightness of the liquid crystal display module provided by this embodiment, in the first aspect, the method corrects the output brightness value of the liquid crystal display module according to the compensation data so that the output brightness value of the liquid crystal display module is the target brightness value, Thus eliminating the LCD display module Mura. In this method, the grayscale-luminance segmented conversion function represents the brightness conversion relationship of the liquid crystal display module, and the grayscale-luminance segmented conversion function coefficients are based on the grayscale values and output brightness values of multiple input signals of the liquid crystal display module Calculated, the gray-to-luminance segmented conversion function can more accurately represent the relationship between the gray value of the actual input signal of the liquid crystal display module and the output brightness value, and can be accurately calculated according to the gray-to-luminance segmented conversion function The compensation data comes out, which improves the elimination effect of eliminating the Mura of the LCD module. In the second aspect, the compensation data of this method is also calculated based on the gray level to be corrected and its target brightness value. Therefore, the input signal passes through the compensation data After the corrected brightness, the output brightness is the target brightness, which eliminates the Mura phenomenon of the device. This method sets the target brightness value of the grayscale output to be corrected according to the gamma relationship. The gamma value of the LCD module after Demura meets the requirements, and there is no need for subsequent Performing gamma correction improves the generation efficiency compared to the prior art.

As shown in FIG. 4, FIG. 4 is a schematic structural diagram of a brightness Demura system of a liquid crystal display module according to another embodiment of the present invention. The brightness Demura system of the liquid crystal display module includes:

The first setting module 301 is used to set the gray values of multiple input signals, and respectively obtain the brightness values of the input signals displayed on the liquid crystal display module.

Specifically, the first setting module 301 sets the gray values of multiple signals, and inputs the multiple signals into the liquid crystal display module. The liquid crystal display module displays the signal, and the brightness value acquisition device is used to acquire the display of the liquid crystal display module. The brightness value of the signal, the brightness value displayed by the liquid crystal display module and the gray value of the multiple input signals are in one-to-one correspondence.

The solving module 302 is used to solve the coefficients of the gray-luminance segmented conversion function by fitting according to the gray values of the multiple input signals and the corresponding brightness values. The gray-luminance segmented conversion function represents the liquid crystal display Module brightness conversion relationship.

Specifically, the solving module 302 substitutes the gray values and corresponding brightness values of the multiple input signals into the gray-luminance segmented conversion function, and calculates the coefficients of the gray-luminance segmented conversion function by using a fitting method , Where the grayscale-luminance segmented conversion function is expressed by a polynomial function at low grayscale, and expressed by an exponential function at high grayscale, and the grayscale-luminance segmented transfer function is:

It should be said that in each liquid crystal display module, the solving module 302 solves the coefficients of the gray-to-luminance segmented conversion function by fitting according to the gray value of the input signal and the corresponding brightness value, according to The grayscale-luminance segmentation conversion function solved by the data of the liquid crystal display module can more accurately represent the relationship between the grayscale value of the input signal of the liquid crystal display module and the output brightness value.

The second setting module 303 is configured to set the gray value of the gray scale to be corrected for each input of the liquid crystal display module, and obtain the target brightness value of the gray scale output to be corrected according to the gamma relationship.

Specifically, the second setting module 303 sets the gray values of the gray levels to be corrected, and according to the gamma relationship between the gray values of the gray levels to be corrected and the output target brightness value, the correspondence of the S gray levels to be corrected is obtained Output target brightness value;

The gamma relationship is:

It should be noted that the gray level to be corrected is a target gray value of the input signal. Gamma is a physical property of the liquid crystal display module. When the input signal and output signal displayed by the liquid crystal display module conform to the Gamma curve The display of the liquid crystal display module conforms to the visual characteristics of the human eye, which is comfortable when the human eye observes the display of the liquid crystal display module. That is, when the relationship curve between the gray value of the gray scale to be corrected and the output target brightness value of the liquid crystal display module satisfies the Gamma curve, the display of the liquid crystal display module conforms to the visual characteristics of the human eye, and the human eye is comfortable when viewing the display device. The normal range of gamma value is (0, 2.7).

The processing module 304 is configured to obtain compensation data corresponding to each gray level to be corrected according to the target brightness value, the gray-to-luminance segmentation conversion function, and the gray level to be corrected.

The processing module 304 needs to select the specific functional relationship in the gray-to-luminance segmentation conversion function according to the specific gray value of the gray level to be corrected to solve the compensation data corresponding to the gray level to be corrected, and the gray level to be corrected corresponds to the compensation data of. Different compensation data is solved according to different gray values of the gray level to be corrected. In addition, a compensation data table including a plurality of compensation data of gray levels to be corrected is stored in the liquid crystal display module.

The correction module 305 is used to correct the brightness value output by the liquid crystal display module using the compensation data, so that the brightness value output by the liquid crystal display module is the target brightness value.

For the input signal of the liquid crystal display module, the correction module 305 may search for the compensation data corresponding to the gray value in the compensation data table according to the specific gray value of the input signal. Therefore, the brightness value output by the signal is corrected according to the compensation data, so that the brightness value output by the liquid crystal display module is the target brightness value. Corresponding to the input signal with the same gray value, the brightness value output by the signal is adjusted to the target brightness value, thereby eliminating the mura phenomenon of the liquid crystal display module.

As can be seen from the Demura system of the brightness of the liquid crystal display module provided in this embodiment, the correction module 305 in the system corrects the output brightness value of the liquid crystal display module according to the compensation data so that the output brightness value of the liquid crystal display module is the target brightness Value, thereby eliminating the LCD display module Mura. The gray-to-luminance segmented conversion function in the system represents the brightness conversion relationship of the liquid crystal display module, and the gray-to-luminance segmented conversion function coefficient is the gray value of the solution module 302 according to a plurality of input signals of the liquid crystal display module Calculated with the output brightness value, the gray-to-luminance segmented conversion function can more accurately represent the relationship between the gray value of the actual input signal of the liquid crystal display module and the output brightness value, according to the gray-to-luminance segmented conversion The function can accurately calculate the compensation data, thereby improving the elimination effect of eliminating the liquid crystal display module Mura.

As shown in FIG. 5, FIG. 5 is a schematic structural diagram of a brightness Demura system of a liquid crystal display module according to another embodiment of the present invention. The system includes:

The first setting module 401 is used to set the gray values of multiple input signals and obtain the brightness values displayed by the multiple input signals on the liquid crystal display module.

Specifically, the first setting module 401 sets the gray value of the N signals, and inputs the N signals into the liquid crystal display module. The liquid crystal display module displays the signal, and the brightness value acquisition device is used to obtain the liquid crystal display module display. For the brightness value of the signal, the N brightness values obtained correspond to the gray values of the N signals in one-to-one correspondence. The relationship of the gray values of the N signals set by the first setting module 401 is as follows: 0≤g ₁ (x,y)<g ₂ (x,y)<...<g _N1 (x,y)<g _N1+1 (x,y)<g _N1+2 (x,y)<...<g _N (x,y), where g _N1 (x,y)<G, g _N (x,y) ≤G _max , N-1≥N ₁ ≥K+1, the first setting module 401 sequentially inputs the above N signals into the liquid crystal display module, sequentially obtains the brightness value of the signal displayed by the liquid crystal display module, and obtains the corresponding The N brightness values are: f(g ₁ (x,y); x,y), f(g ₂ (x,y); x,y),...f(g _N1 (x,y); x,y), f(g _N1+1 (x,y); x,y), f(g _N1+2 (x,y); x,y),...f(g _N (x,y ); x, y). Among them, for a commonly used 8-bit display, the gray value of the input signal ranges from 0 to 255, and the N values are related to the number of solving coefficients.

The solving module 402 is used to solve the coefficients of the gray-to-luminance segmented conversion function by fitting based on the gray values of the multiple input signals and the corresponding brightness values. The gray-to-luminance segmented conversion function represents the liquid crystal display Module brightness conversion relationship.

Among them, the solving module 402 substitutes the gray values and corresponding brightness values of the N input signals into the gray-to-luminance segmented conversion function, and calculates the coefficients of the gray-to-luminance segmented conversion function by using a fitting method, The grayscale-luminance segmentation conversion function is shown in the following formula:

Specifically, the solving module 402 compares the gray values g ₁ (x, y), g ₂ (x, y), ..., g _N1 (x, y) of the first N ₁ input signals and the corresponding output brightness values f(g ₁ (x,y); x,y), f(g ₂ (x,y); x,y),...f(g _N1 (x,y); x,y) is substituted into gray In the polynomial formula of the degree-luminance piecewise conversion function, the coefficient a _k (x,y) in the polynomial function is solved, and then g _N1+1 (x,y), g _N1+2 (x,y),. .., g _N (x,y) and the corresponding f(g _N1+1 (x,y); x,y), f(g _N1+2 (x,y); x,y),... f(g _N (x,y); x,y) is substituted into the formula of the exponential function of the grayscale-luminance piecewise conversion function, and the coefficient b ₀ (x,y) of the formula of the exponential function is solved by the curve fitting method ) And b ₁ (x,y). When the coefficients of the grayscale-luminance segmented conversion function are solved, the grayscale-luminance segmented conversion function is solved, that is, the brightness conversion relation is solved.

The second setting module 403 is used to set the gray values of the gray scales to be corrected input by the liquid crystal display module, and obtain the target brightness values of the S gray scales to be corrected output according to the gamma relationship.

Specifically, the second setting module 403 sets the gray values of the S gray levels to be corrected to D ₁ , D ₂ , ... D _S , respectively, and solves the target brightness values output by the S gray levels to be corrected according to the gamma relationship : L ₁ , L ₂ , ... L _S.

Among them, the gamma relationship is as follows:

The first calculation module 404 is used to input the target brightness corresponding to the output of the S gray levels to be corrected into the gray-to-luminance segmentation conversion function, and solve the gray value of the input signal corresponding to the gray levels to be corrected, namely The gray value of the input signal is solved as: g _i (x, y) = f ^-1 (L _i ; x, y), i = 1, 2, ..., S.

Specifically, if the gray value D ₁ of the gray level to be corrected is within the range of [0, G), the first calculation module 404 inputs the target luminance value L ₁ corresponding to the gray level D ₁ to be corrected to the gray-luminance points The polynomial formula of the segment transfer function is as follows:

The second calculation module 405 is configured to obtain the compensation data of the gray level to be corrected according to the gray level to be corrected and the gray value of the corresponding input signal.

Specifically, the second calculation module 405 calculates the compensation data based on the compensation data generation formula based on the gray level to be corrected and the gray value of the corresponding input signal, and the compensation data generation formula is:

ΔD _i (x,y)=g _i (x,y)-D _i (5)

The second calculation module 405 generates the compensation data ΔD ₁ (x, y) of the gray level D ₁ to be corrected according to the above formula, and accordingly, respectively generates the gray levels D ₁ , D ₂ , ... to be corrected according to the compensation data generation formula D _S corresponding compensation data _{ΔD 1 (x, y),} ΔD 2 (x, y), ..., ΔD S (x, y).

It should also be noted that the first calculation module 404 and the second calculation module 405 of this embodiment are refinement modules of the processing module 304 of the previous embodiment.

The correction module 406 is used to correct the brightness value output by the liquid crystal display module using the compensation data, so that the brightness value output by the liquid crystal display module is the target brightness value.

Specifically, the correction module 406 calculates a correction amount according to the compensation data, and then corrects the brightness value of the signal output according to the correction amount.

In the embodiment of the present invention, the first setting module 401 sets the two-dimensional coordinates of each signal to be (x, y), the value of x is 0, 1, ..., 3839, and the value of y is 0, 1 respectively ,..., 2519, G _max is the maximum value of the pixel gray scale is 255, 0≤g(x,y)≤255, the cut-off point G of the grayscale-luminance piecewise conversion function is set to 200, the order of the polynomial function The number K is set to 4. The gray scale-luminance segmentation conversion function of the LCD module representing the brightness conversion relationship is as follows:

In the embodiment of the present invention, the number N of input signals set by the first setting module 401 is 6, and the first setting module 401 sets the gray values of the input signals to g ₁ (x, y)=0 and g ₂ ( x, y) = 20, g ₃ (x, y) = 50, g ₄ (x, y) = 100, g ₅ (x, y) = 200, g ₆ (x, y) = 255 are sequentially input to the liquid crystal In the display module, the 6 input signals corresponding to the 6 brightness values displayed in the liquid crystal display module are f(g ₁ (x,y); x,y), f(g ₂ (x,y) ; X,y), f(g ₃ (x,y); x,y), f(g ₄ (x,y); x,y), f(g ₅ (x,y); x,y) , F(g ₆ (x, y); x, y). Since the cut-off point G of the grayscale-luminance segmentation conversion function is 200, the first setting module 401 inputs 0, 20, 50, 100 and the corresponding display brightness values into the formula (a), and the solving module 402 adopts the least squares curve The combined method solves the coefficients a ₀ (x,y), a ₁ (x,y), a ₂ (x,y), a ₃ (x,y), a ₄ (x,y) of the formula (a), Then use the curve fitting method to solve the coefficients b ₀ (x, y) and b ₁ (x, y) in the formula (b). Thus, the expression of the grayscale-luminance piecewise conversion function is solved.

In the embodiment of the present invention, after the solving module 402 solves the expression of the gray-to-luminance piecewise conversion function, the second setting module 403 sets the value of the number S of gray levels to be corrected to 3 and 3 grays to be corrected The levels are: D ₁ = 24, D ₂ = 65, D ₃ = 220, and the second setting module 403 inputs the value of the gray level to be corrected into the gamma relationship (2), where the Gamma value is taken 2.2. Obtain the corresponding target brightness values as L ₁ , L ₂ and L _{3 respectively} .

Where the gray value 24 of the gray level D ₁ to be corrected is in the range of [0, 200), the first calculation module 404 brings the target luminance value L ₁ corresponding to the gray level D ₁ to be corrected into the formula (a), to obtain The following formula:

The gray value g ₂₄ (x, y) of the input signal of the target luminance value L ₁ is solved by the Newton iteration method from the above formula. The compensation data of the gray level 24 to be corrected solved by the second calculation module 405 is:

ΔD ₁ (x,y)=g ₂₄ (x,y)-24 (d)

When the gray value 65 of the gray level D ₂ to be corrected is within the range of [0,200), the first calculation module 404 brings the target luminance value L ₂ corresponding to the gray level D ₂ to be corrected into the formula (a), and the following formula is obtained:

The gray value g ₆₅ (x, y) of the input signal of the target luminance value L ₂ is solved by the Newton iteration method from the above formula. The compensation data of the gray level 65 to be corrected solved by the second calculation module 405 is:

ΔD ₂ (x,y)=g ₆₅ (x,y)-65 (f)

When the gray value 220 of the gray level D ₃ to be corrected is within the range of [200,255), the first calculation module 404 brings the target luminance value L ₃ corresponding to the gray level D ₃ to be corrected into the formula (a), and the following formula is obtained:

The gray value g ₂₀₀ (x, y) of the input signal of the target luminance value L ₃ is directly solved from the above formula, and the compensation data of the gray level 220 to be corrected solved by the second calculation module 405 is:

ΔD ₃ (x,y)=g ₂₂₀ (x,y)-220 (h)

As can be seen from the Demura system that provides the brightness of the liquid crystal display module in this embodiment, in the first aspect, the correction module 406 in the system corrects the output brightness value of the liquid crystal display module according to the compensation data so that the output brightness value of the liquid crystal display module is The target brightness value, thus eliminating the LCD display module Mura. The grayscale-luminance segmented conversion function represents the brightness conversion relationship of the liquid crystal display module. The grayscale-luminance segmented conversion function coefficients are obtained by the solution module 402 according to the grayscale value and output brightness of multiple input signals of the liquid crystal display module Calculated by the value, the gray-to-luminance segmented conversion function can more accurately represent the relationship between the gray value of the actual input signal of the liquid crystal display module and the output brightness value, according to the gray-to-luminance segmented conversion function can be accurate The calculated compensation data improves the elimination effect of eliminating the LCD module Mura. In the second aspect, the compensation data in the system is also calculated based on the gray level to be corrected and its target brightness value. Therefore, after the brightness of the input signal is corrected by the compensation data, the output brightness is the target brightness, eliminating the Mura phenomenon of the device The system sets the target brightness value of the grayscale output to be corrected according to the gamma relationship. The gamma value of the Demura liquid crystal display module meets the requirements, and subsequent gamma correction is not required. Compared with the prior art, the generation efficiency is improved.

6 is a schematic structural diagram of a computing device according to another embodiment of the present invention. As shown in FIG. 6, the computing device 5 of this embodiment includes: a processor 501, a memory 502, and a computer program 503 stored in the memory 502 and executable on the processor 501, such as the brightness of the LCD module Demura method program. When the processor 501 executes the computer program 503, the steps in the embodiment of the above-mentioned brightness Demura method of the liquid crystal display module are implemented, for example, steps 101 to 105 shown in FIG. 1. Alternatively, when the processor 501 executes the computer program 503, the functions of each module/unit in the above device embodiments are realized, for example, the first setting module 301, the solving module 302, the second setting module 303, the processing module 304, and the correction shown in FIG. 4 Function of module 305.

Exemplarily, the computer program 503 of the Demura method of the brightness of the liquid crystal display module mainly includes: setting the gray values of multiple input signals, respectively obtaining the brightness values of the input signals displayed on the liquid crystal display module; Degree value and corresponding brightness value, the coefficients of the gray-to-luminance segmented conversion function are solved by fitting, the gray-to-luminance segmented conversion function represents the brightness conversion relationship of the liquid crystal display module; setting the liquid crystal display module Set the gray value of each input gray level to be corrected, and obtain the target brightness value of each gray level output to be corrected according to the gamma relationship; according to the target brightness value, the gray-luminance segmentation conversion function formula and the gray level to be corrected, get Compensation data corresponding to each gray level to be corrected; the compensation data is used to correct the brightness value output by the liquid crystal display module so that the brightness value output by the liquid crystal display module is the target brightness value. The computer program 503 may be divided into one or more modules/units, and the one or more modules/units are stored in the memory 502 and executed by the processor 501 to complete the present invention. The one or more modules/units may be a series of computer program instruction segments capable of performing specific functions. The instruction segments are used to describe the execution process of the computer program 503 in the computing device 5. For example, the computer program 503 can be divided into the functions of the first setting module 301, the solving module 302, the second setting module 303, the processing module 304, and the correction module 305 (modules in the virtual device). The specific functions of each module are as follows: The setting module 301 is used to set the gray values of multiple input signals and obtain the brightness values of the multiple input signals displayed on the liquid crystal display module; the solving module 302 is used to determine the gray values and corresponding brightness of the multiple input signals Value, the coefficient of the grayscale-luminance segmented conversion function is solved by fitting, the grayscale-luminance segmented conversion function represents the brightness conversion relationship of the LCD module; the second setting module 303 is used to set the LCD module Set the gray value of each input gray level to be corrected, and obtain the target brightness value of each gray level output to be corrected according to the gamma relationship; the processing module 304 is used to calculate the target brightness value, the gray-luminance segmentation conversion function, and the Correct the gray scale to obtain the compensation data corresponding to each gray scale to be corrected; the correction module 305 is used to correct the brightness value output by the liquid crystal display module using the compensation data so that the brightness value output by the liquid crystal display module is the target brightness value.

The computing device 5 may include, but is not limited to, a processor 501 and a memory 502. Those skilled in the art may understand that FIG. 6 is only an example of the computing device 5 and does not constitute a limitation on the computing device 5, and may include more or fewer components than shown, or combine certain components, or different components For example, the computing device may also include input and output devices, network access devices, buses, and so on.

The so-called processor 501 may be a central processing unit (Central Processing Unit, CPU), or other general-purpose processors, digital signal processors (Digital Signal Processor, DSP), application specific integrated circuits (Application Specific Integrated Circuit, ASIC), Ready-made programmable gate array (Field-Programmable Gate Array, FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or the processor may be any conventional processor or the like.

The memory 502 may be an internal storage unit of the computing device 5, such as a hard disk or a memory of the computing device 5. The memory 502 may also be an external storage device of the computing device 5, such as a plug-in hard disk equipped on the computing device 5, a smart memory card (Smart) Card (SMC), a secure digital (SD) card, and a flash memory card (Flash Card) etc. Further, the memory 502 may also include both the internal storage unit of the computing device 5 and the external storage device. The memory 502 is used to store computer programs and other programs and data required by the computing device. The memory 502 may also be used to temporarily store data that has been or will be output.

Those skilled in the art can clearly understand that for the convenience and conciseness of description, only the above-mentioned division of each functional unit and module is used as an example for illustration. In practical applications, the above-mentioned functions can be assigned by different functional units, Module completion means that the internal structure of the device is divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiment may be integrated into one processing unit, or each unit may exist alone physically, or two or more units may be integrated into one unit. The above integrated unit may use hardware It can also be implemented in the form of software functional units. In addition, the specific names of each functional unit and module are only for the purpose of distinguishing each other, and are not used to limit the protection scope of the present application. For the specific working processes of the units and modules in the above system, reference may be made to the corresponding processes in the foregoing method embodiments, which will not be repeated here.

Sequence listing free content

In the above embodiments, the description of each embodiment has its own emphasis. For a part that is not detailed or recorded in an embodiment, you can refer to the related descriptions of other embodiments.

Those of ordinary skill in the art may realize that the units and algorithm steps of the examples described in conjunction with the embodiments disclosed herein can be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are executed in hardware or software depends on the specific application of the technical solution and design constraints. Professional technicians can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the present invention.

Claims

A Demura method for the brightness of a liquid crystal display module, characterized in that the method includes:

Set the gray value of multiple input signals to obtain the brightness value of the input signal displayed on the liquid crystal display module;

According to the gray values of the plurality of input signals and the corresponding brightness values, the coefficients of the gray-luminance segmented conversion function are solved by fitting, and the gray-luminance segmented conversion function represents the liquid crystal Display module brightness conversion relationship;

Setting the gray value of each gray level to be corrected of each input of the liquid crystal display module, and obtaining the target brightness value of the gray level to be corrected output according to the gamma relationship;

Obtaining compensation data corresponding to each gray level to be corrected according to the target brightness value, the gray-to-luminance segmentation conversion function, and the gray level to be corrected;

The compensation data is used to correct the brightness value output by the liquid crystal display module so that the brightness value output by the liquid crystal display module is the target brightness value.
The method according to claim 1, wherein the grayscale-luminance segmented conversion function is represented by a polynomial function in low grayscale and an exponential function in high grayscale, and the grayscale-luminance segmented conversion The function is:

Among them, (x, y) is the two-dimensional coordinates of each input signal, a k (x, y), b 0 (x, y) and b 1 (x, y) are coefficients, k = 0, 1, 2 ,...,K,G are the segmentation points of the grayscale-luminance segmentation conversion function, K is the order of the polynomial, g(x,y) is the grayscale value of the input signal, f(g(x ,y); x,y) is the output brightness value.
The method according to claim 1, wherein the gray value of the gray level to be corrected of each input of the liquid crystal display module is set, and the target brightness value of the gray level output to be corrected is obtained according to a gamma relationship The steps include:

Set the gray values of the gray levels to be corrected, and obtain the corresponding output target brightness values of the S gray levels to be corrected according to the gamma relationship between the gray values of the gray levels to be corrected and the output target brightness values;

The gamma relationship is:

Among them, D i is the gray value of the i-th gray level to be corrected, L i is the i-th target brightness value, i=1, 2, ..., S, and L max is the maximum value displayed by the liquid crystal display module Brightness value, L min is the minimum brightness value displayed by the liquid crystal display module, r is the gamma value of the liquid crystal display module, 0≤r≤24.
The method according to claim 3, characterized in that, according to the target luminance value, the grayscale-luminance segmentation conversion function, and the grayscale to be corrected, the corresponding to each grayscale to be corrected is obtained The steps to compensate data include:

Input the target brightness corresponding to the output of the S gray scales to be corrected into the gray-to-luminance segmentation conversion function, find the gray value of the input signals corresponding to the gray scales to be corrected, and solve the S Correct the gray value of the input signal corresponding to the gray scale, the gray value is: g i (x, y) = f -1 (L i ; x, y), i = 1, 2, ..., S ;

The compensation data of the gray level to be corrected is obtained according to the gray level to be corrected and the gray value of the corresponding input signal.
The method according to claim 4, wherein the step of obtaining the compensation data of the gray level to be corrected according to the gray level to be corrected and the gray value of the corresponding input signal comprises:

Based on the gray level to be corrected and the gray value of the corresponding input signal, compensation data is calculated according to a compensation data generation formula, and the compensation data generation formula is:

ΔD i (x,y)=g i (x,y)-D i

Among them, D i is the ith gray level to be corrected, the corresponding g i (x, y) is the gray value of the input signal and ΔD i (x, y) is the compensation data, i=1, 2,... , S.
A brightness Demura system of a liquid crystal display module, the system includes:

The first setting module is used to set the gray values of multiple input signals and respectively obtain the brightness values of the input signals displayed on the liquid crystal display module;

The solving module is used to solve the coefficients of the grayscale-luminance segmentation conversion function by fitting according to the grayscale values of the multiple input signals and the corresponding brightness values. The function represents the brightness conversion relationship of the liquid crystal display module;

A second setting module, configured to set the gray value of each gray level to be corrected of each input of the liquid crystal display module, and obtain the target brightness value of the gray level to be corrected output according to the gamma relationship;

A processing module, configured to obtain compensation data corresponding to each gray level to be corrected according to the target luminance value, the gray-to-luminance segmentation conversion function, and the gray level to be corrected;

The correction module is used for correcting the brightness value output by the liquid crystal display module using the compensation data, so that the brightness value output by the liquid crystal display module is the target brightness value.
The system according to claim 6, wherein the processing module comprises:

The first calculation module is used to input the target brightness corresponding to the output of the S gray levels to be corrected into the gray-to-luminance segmentation conversion function, and to calculate the gray value of the input signal corresponding to the S gray levels to be corrected, Solve the gray values of the input signals corresponding to the S gray levels to be corrected, the gray values are: g i (x, y) = f -1 (L i ; x, y), i = 1, 2,...,S;

The second calculation module is used to obtain the compensation data of the gray level to be corrected according to the gray level to be corrected and the gray value of the corresponding input signal.
The system according to claim 7, wherein the second calculation module is specifically configured to calculate and obtain compensation data according to a compensation data generation formula based on the gray value of the gray level to be corrected and its corresponding input signal, and The formula for generating compensation data is:

ΔD i (x,y)=g i (x,y)-D i

Among them, D i is the ith gray level to be corrected, the corresponding g i (x, y) is the gray value of the input signal and ΔDi(x, y) is the compensation data, i=1, 2, ..., S.
A computing device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, when the processor executes the computer program, it is implemented as claimed in claims 1 to 5 any one of the method steps.
A computer-readable storage medium storing a computer program, characterized in that when the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 5 are implemented.