Liquid crystal display device and backlight driving method thereof

Abstract

The invention provides a liquid crystal display device and a backlight driving method thereof, and a backlight module of the liquid crystal display device comprises a light emitting unit, a calculation unit, a comparison unit and a control unit, the calculation unit is used for calculating a first preset backlight brightness value of a corresponding backlight partition according to a partition average brightness value and a partition maximum brightness value of a display partition in a current frame display picture; the comparison unit is used for comparing a second preset backlight brightness value of the backlight subarea in the previous frame of display picture with the first preset backlight brightness value and outputting a comparison result, and the control unit is used for outputting a first brightness driving value of the backlight subarea in the current frame of display picture based on the comparison result. The light-emitting unit emits light in the backlight subarea based on the first brightness driving value, the backlight brightness of the backlight subarea under the dark-state display picture is improved, and therefore the detail display capacity of the liquid crystal display device is improved.

Description

Technical Field

[0001] The present application relates to the field of display technology, and in particular to a liquid crystal display device and a backlight driving method thereof. Background Art

[0002] Liquid Crystal Display (LCD) with Mini Light-Emitting Diode (Mini-LED) backlight dynamically adjusts the backlight brightness of the backlight module through the local dimming (LD) algorithm to achieve ultra-high contrast of the display screen. The LD algorithm counts the brightness information of the display screen corresponding to each backlight partition in the backlight module, and then selects the appropriate backlight brightness according to the brightness information. The higher the brightness of a certain area of ​​the display screen, the higher the brightness of the corresponding backlight partition. When a certain area of ​​the display screen is a black screen, the corresponding backlight partition does not emit light. If the display screen to be displayed is a dark screen with a small and scattered bright area, such as a starry sky screen, the average brightness of the display screen and the average brightness of the corresponding backlight partition are both very low, then a backlight brightness value very close to zero will be obtained through the LD algorithm. Once the backlight accuracy is not high, the backlight module will eventually output the backlight in a state where the backlight brightness value is zero, resulting in loss of display screen details, so that the detail display capability of the liquid crystal display device is insufficient. Summary of the invention

[0003] The present application provides a liquid crystal display device and a backlight driving method thereof, so as to solve the problem that the liquid crystal display device has insufficient detail display capability when displaying dark images.

[0004] In a first aspect, the present application provides a liquid crystal display device, comprising:

[0005] A display panel, wherein the display panel includes a plurality of display partitions;

[0006] A backlight module, the backlight module comprising:

[0007] A light emitting unit, the light emitting unit comprising a plurality of backlight subareas corresponding to the display subareas;

[0008] A calculation unit, the calculation unit is used to calculate a first preset backlight brightness value of the backlight partition corresponding to the display partition according to a partition average brightness value and a partition maximum brightness value of the display partition in a current frame display picture;

[0009] A comparison unit, the comparison unit is used to compare the second preset backlight brightness value of the backlight partition in the previous frame display picture with the first preset backlight brightness value, and output a comparison result;

[0010] A control unit is used to output a first brightness driving value of the backlight partition in a current frame display picture based on the comparison result, so that the light-emitting unit emits light in the backlight partition based on the first brightness driving value.

[0011] In the liquid crystal display device provided in the present application, the calculation unit is used to calculate the first preset backlight brightness value based on the partition maximum brightness value, the partition average brightness value, and the second preset weight value corresponding to the partition average brightness value.

[0012] In the liquid crystal display device provided in the present application, the control unit is used to output the first brightness driving value based on the partition maximum brightness value, the first driving weight value corresponding to the partition maximum brightness value, the partition average brightness value and the second driving weight value corresponding to the partition average brightness value, wherein the first driving weight value is determined according to the first preset weight value and the third driving weight value corresponding to the partition maximum brightness value of the backlight partition in the previous frame display image, and the second driving weight value is determined according to the second preset weight value and the fourth driving weight value corresponding to the partition average brightness value of the backlight partition in the previous frame display image.

[0013] In the liquid crystal display device provided in the present application, the control unit is used to calculate the first brightness driving value according to a first preset relationship, and the first preset relationship is: L(x)=k1*L_max(x)+k2*L_av(x), wherein L(x) is the first brightness driving value, L_max(x) is the maximum brightness value of the partition, L_av(x) is the average brightness value of the partition, k1 is the first driving weight value, and k2 is the second driving weight value.

[0014] In the liquid crystal display device provided in the present application, the control unit is also used to calculate the size of the other of the first drive weight value and the second drive weight value based on one of the first drive weight value and the second drive weight value and a second preset relationship formula, and the second preset relationship formula is: k1+k2=1.

[0015] In the liquid crystal display device provided in the present application, the control unit is used to determine the third driving weight value as the first driving weight value of the backlight partition in the current frame display picture when the comparison result is that the first preset backlight brightness value is the same as the second preset backlight brightness value, and to determine the fourth driving weight value as the second driving weight value of the backlight partition in the current frame display picture.

[0016] In the liquid crystal display device provided in the present application, the control unit is used to determine whether the average grayscale value of the current frame display screen satisfies a first preset threshold and whether the maximum backlight grayscale value of all the backlight partitions in the current frame display screen satisfies a second preset threshold when the comparison result is that the first preset backlight brightness value is different from the second preset backlight brightness value. If not, the first preset weight value is determined as the first driving weight value, and the second preset weight value is determined as the second driving weight value.

[0017] In the liquid crystal display device provided in the present application, the calculation unit is also used to calculate the average grayscale value of the current frame display image and the maximum backlight grayscale value of all the backlight partitions in the current frame display image when the comparison result is that the first preset backlight brightness value is different from the second preset backlight brightness value.

[0018] In the liquid crystal display device provided in the present application, if the conditions are met, the control unit is also used to determine the first driving weight value of the backlight partition in the current frame display picture according to the first preset weight value and the weight adjustment value, and to determine the second driving weight value of the backlight partition in the current frame display picture according to the second preset weight value and the weight adjustment value.

[0019] In the liquid crystal display device provided in the present application, the control unit is used to determine the first driving weight value of the backlight partition in the current frame display picture based on the first preset weight value, the weight adjustment value and the third preset relationship formula, and the third preset relationship formula is: ky1+k0=k1, wherein ky1 is the first preset weight value, k0 is the weight adjustment value, and k1 is the first driving weight value of the backlight partition in the current frame display picture.

[0020] In a second aspect, the present application further provides a backlight driving method for a liquid crystal display device, wherein the liquid crystal display device comprises a display panel and a backlight module, wherein the display panel comprises a plurality of display partitions, and the backlight module comprises a plurality of backlight partitions corresponding to the display partitions, and the backlight driving method comprises:

[0021] Calculate a first preset backlight brightness value of the backlight partition corresponding to the display partition according to a partition average brightness value and a partition maximum brightness value of the display partition in the current frame display picture;

[0022] Compare the second preset backlight brightness value of the backlight partition in the previous frame display picture with the first preset backlight brightness value, and output the comparison result;

[0023] Outputting a first brightness driving value of the backlight partition in a current frame display picture based on the comparison result;

[0024] The backlight partitions are controlled to emit light based on the first brightness driving value.

[0025] In the backlight driving method provided in the present application, the step of calculating the first preset backlight brightness value of the backlight partition corresponding to the display partition according to the average brightness value of the partition in the current frame display picture and the maximum brightness value of the partition includes:

[0026] Calculating the average brightness value of the display partition in the current frame display picture;

[0027] Calculating the maximum brightness value of the display partition in the current frame display picture;

[0028] The first preset backlight brightness value is calculated based on a first preset weight value corresponding to the partition maximum brightness value, a second preset weight value corresponding to the partition maximum brightness value, the partition average brightness value, and the partition maximum brightness value.

[0029] In the backlight driving method provided in the present application, the step of outputting the first brightness driving value of the backlight partition in the current frame display picture based on the comparison result includes:

[0030] Determine, based on the comparison result, a first driving weight value corresponding to the maximum brightness value of the partition and a second driving weight value corresponding to the average brightness value of the partition;

[0031] The first brightness driving value is output according to the first driving weight value, the second driving weight value, the partition average brightness value, and the partition maximum brightness value.

[0032] In the backlight driving method provided in the present application, the step of outputting the first brightness driving value according to the first driving weight value, the second driving weight value, the partition average brightness value and the partition maximum brightness value includes:

[0033] The first brightness driving value is output according to the first preset relationship, the first driving weight value, the second driving weight value, the partition average brightness value and the partition maximum brightness value. The first preset relationship is: L(x)=k1*L_max(x)+k2*L_av(x), wherein L(x) is the first brightness driving value, L_max(x) is the partition maximum brightness value, L_av(x) is the partition average brightness value, k1 is the first driving weight value, and k2 is the second driving weight value.

[0034] In the backlight driving method provided in the present application, the size of the other of the first driving weight value and the second driving weight value is calculated based on one of the first driving weight value and the second driving weight value and a second preset relationship, and the second preset relationship is: k1+k2=1.

[0035] In the backlight driving method provided in the present application, the step of determining the first driving weight value corresponding to the partition maximum brightness value and the second driving weight value corresponding to the partition average brightness value based on the comparison result includes:

[0036] If the comparison result is that the second preset backlight brightness value is the same as the first preset backlight brightness value, the third driving weight value corresponding to the maximum brightness value of the backlight partition in the previous frame display image is determined as the first driving weight value, and the fourth driving weight value corresponding to the average brightness value of the backlight partition in the previous frame display image is determined as the second driving weight value.

[0037] In the backlight driving method provided in the present application, the step of determining the first driving weight value corresponding to the partition maximum brightness value and the second driving weight value corresponding to the partition average brightness value based on the comparison result includes:

[0038] If the comparison result is that the second preset backlight brightness value is different from the first preset backlight brightness value, determining whether the average grayscale value of the current frame display image satisfies a requirement of being less than a first preset threshold value and whether the maximum backlight grayscale values ​​of all the backlight subareas in the current frame display image satisfies a requirement of being less than a second preset threshold value;

[0039] If not, the first preset weight value is determined as the first driving weight value, and the second preset weight value is determined as the second driving weight value.

[0040] The backlight driving method provided in the present application also includes:

[0041] If satisfied, obtain the weight adjustment value;

[0042] Determining the first driving weight value according to the first preset weight value and the weight adjustment value;

[0043] The second driving weight value is determined according to the second preset weight value and the weight adjustment value.

[0044] In the backlight driving method provided in the present application, the step of determining the first driving weight value according to the first preset weight value and the weight adjustment value includes:

[0045] The first driving weight value is determined according to the first preset weight value, the weight adjustment value and a third preset relationship, wherein the third preset relationship is: ky1+k0=k1, wherein ky1 is the first preset weight value, k0 is the weight adjustment value, and k1 is the first driving weight value.

[0046] The liquid crystal display device provided in the present application compares the second preset backlight brightness value of the backlight partition in the previous frame display picture and the first preset backlight brightness value in the current frame display picture through a comparison unit, so that the control unit outputs a brightness driving value corresponding to the comparison result, so that the light-emitting unit emits light in the corresponding backlight partition based on the brightness driving value, thereby improving the backlight brightness of the backlight partition in the dark display picture, and then improving the detail display capability of the liquid crystal display device. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 A block diagram of a liquid crystal display device provided in an embodiment of the present application;

[0048] Figure 2 A first block diagram of a backlight module provided in an embodiment of the present application;

[0049] Figure 3 A second block diagram of a backlight module provided in an embodiment of the present application;

[0050] Figure 4 A first flow chart of a driving method for a liquid crystal display device provided in an embodiment of the present application;

[0051] Figure 5 for Figure 4 A specific flow chart of S10 in FIG.

[0052] Figure 6 This is a second flow chart of the driving method of the liquid crystal display device provided in the embodiment of the present application. DETAILED DESCRIPTION

[0053] The technical solutions in the embodiments of the present application will be described below in conjunction with the accompanying drawings in the embodiments of the present application. The described embodiments are only used to explain the ideas created by the present invention and should not be regarded as limiting the scope of protection of the present application.

[0054] like Figure 1 As shown, the liquid crystal display device 100 provided in this embodiment includes a display panel 10 and a backlight module 20. The display panel 10 includes a display area and a non-display area other than the display area. The display area includes a plurality of display subareas AA1. The display area AA is used to provide a display image. Each display subarea AA1 is provided with a plurality of pixels.

[0055] like Figure 2As shown, the backlight module 20 specifically includes a light emitting unit 201 , a calculating unit 202 , a comparing unit 203 and a control unit 204 .

[0056] The light-emitting unit 201 includes a plurality of backlight partitions BA1 corresponding to the display partitions AA1, and each backlight partition BA1 is provided with a plurality of Mini-LEDs. The light-emitting unit 201 is driven by a local dimming (LD) method. There is a one-to-one correspondence between the plurality of backlight partitions BA1 and the plurality of display partitions AA1, that is, each display partition AA1 has a corresponding backlight partition BA1 to provide a backlight source for displaying the picture. The LD algorithm is used to divide the entire light-emitting unit 201 into a plurality of independently drivable backlight partitions BA1. The driving current of the LED of the backlight partition corresponding to the corresponding part is automatically adjusted according to the grayscale to be displayed in different areas of the display picture, so as to realize the individual adjustment of the brightness of each backlight partition BA1 in the light-emitting unit 201, thereby improving the contrast of the display picture.

[0057] The calculation unit 202 is used to calculate the first preset backlight brightness value of the backlight partition BA1 corresponding to the display partition AA1 according to the partition average brightness value and the partition maximum brightness value of the display partition AA1 in the current frame display picture. The first preset backlight brightness value of the backlight partition BA1 in the current frame display picture is related to the display brightness of the display partition AA1 corresponding to the backlight partition BA1 in the current frame display picture, and the size of the preset backlight brightness value of the backlight partition BA1 depends on the size of the display brightness value of the frame display picture corresponding to the display partition AA1 corresponding to the backlight partition BA1.

[0058] The calculation unit 202 obtains the brightness values ​​of all pixels in the display partition AA1 and determines the maximum brightness value of the pixels in the display partition AA1, and determines the maximum brightness value of the pixels in the display partition AA1 as the partition maximum brightness value of the display partition AA1.

[0059] The calculation unit 202 accumulates the brightness values ​​of all pixels in the display partition AA1 to obtain the total brightness value of the display partition AA1, and then obtains the partition average brightness value of the display partition AA1 according to the total brightness value of the display partition AA1 and the number of pixels in the display partition AA1.

[0060] The calculation unit 202 is further used to calculate the first preset backlight brightness value based on the average brightness value of the display partition AA1 corresponding to the backlight partition BA1 in the current frame display picture, the maximum brightness value of the partition of the same display partition AA1, the first preset weight value and the second preset weight value, wherein the first preset weight value is the weight value corresponding to the maximum brightness value of the partition, and the second preset weight value is the weight value corresponding to the average brightness value of the partition. The first preset weight values ​​corresponding to different backlight partitions BA1 in different frame display pictures are the same, and the second preset weight values ​​corresponding to different backlight partitions BA1 in different frame display pictures are the same.

[0061] The first preset weight value is a weight value of a preset partition maximum brightness value stored in the calculation unit 202. The second preset weight value is a weight value of a preset partition average brightness value stored in the calculation unit 202.

[0062] When calculating the brightness value of the backlight partition BA1 based on the LD algorithm, the partition average brightness value and the partition maximum brightness value of the display screen corresponding to this backlight partition BA1 will be referred to. The brightness value of the backlight partition BA1 can be adjusted by adjusting the weight value of the partition maximum brightness value and the partition average brightness value accordingly. Therefore, the preset backlight brightness value of the corresponding backlight partition BA1 can be calculated based on the first preset weight value, the partition maximum brightness value, the second preset weight value and the partition average brightness value. In the LD algorithm, increasing the first preset weight value will increase the brightness of all backlight partitions BA1. The result of this adjustment may be that the details of the initial dark area of ​​the display screen are improved, but the halo of the initial bright area of ​​the display screen becomes serious. Therefore, the size of the first preset weight value should not be too large and should be less than 1.

[0063] The comparison unit 203 is used to compare the second preset backlight brightness value of the backlight partition BA1 in the previous frame display picture with the first preset backlight brightness value, and output the comparison result. The comparison unit 203 compares the preset backlight brightness values ​​of the same backlight partition BA1 in the previous and next frames of display pictures, and outputs a comparison result that the preset backlight brightness values ​​of the same backlight partition BA1 in the previous and next frames of display pictures are the same or different. The comparison unit 203 can also store the preset backlight brightness values ​​of each backlight partition BA1 in different frames of display pictures, so as to compare the preset backlight brightness values ​​of a specific backlight partition BA1 in the previous and next frames of display pictures.

[0064] The control unit 204 is used to output the first brightness driving value of the backlight partition BA1 in the current frame display picture based on the comparison result, so that the light-emitting unit 201 emits light in the corresponding backlight partition based on the first brightness driving value, wherein the first brightness driving value is determined according to the second brightness driving value of the same backlight partition BA1 in the previous frame display picture and the first preset backlight brightness value of the current frame display picture.

[0065] If the first preset backlight brightness value and the second preset backlight brightness value of the same backlight partition BA1 are the same, then the brightness data corresponding to this backlight partition BA1 does not change in the two previous and next frames of display, and there is no need to adjust the detail display capability of this backlight partition BA1 in the current frame display, that is, there is no need to enhance the weight value of the partition maximum brightness value and the weight value of the partition average brightness value corresponding to this display partition BA1.

[0066] In the case of this comparison result, the control unit 204 obtains the first driving weight value corresponding to the previous frame display picture of the backlight partition BA1 and the second driving weight value corresponding to the current frame display picture of the backlight partition BA1, and determines the first driving weight value of the backlight partition BA1 in the previous frame display picture as the first driving weight value of the current frame display picture, and determines the second driving weight value of the backlight partition BA1 in the previous frame display picture as the second driving weight value of the current frame display picture. That is, the first driving weight value of the backlight partition BA1 in the previous and next two frames of display pictures is the same, and the second driving weight value of the backlight partition BA1 in the previous and next two frames of display pictures is the same.

[0067] If the second preset backlight brightness value and the first preset backlight brightness value of the same backlight partition BA1 are different in size, then the brightness data corresponding to this backlight partition BA1 changes in the two previous and subsequent frames, and it is necessary to optimize the detail display capability of this backlight partition BA1 under the current frame display screen, that is, it is necessary to adjust the weight value of the maximum brightness value of the partition corresponding to this display partition BA1 and the weight value of the weighted average brightness value.

[0068] The control unit 204 outputs the first brightness driving value based on the maximum brightness value of the partition, the first driving weight value corresponding to the maximum brightness value of the partition, the average brightness value of the partition, and the second driving weight value corresponding to the average brightness value of the partition. The first driving weight value of the backlight partition in the current frame display picture is determined according to the first preset weight value and the first driving weight value corresponding to the second brightness driving value, wherein the first driving weight value is determined according to the first preset weight value and the third driving weight value corresponding to the maximum brightness value of the partition of the same backlight partition in the previous frame display picture, and the second driving weight value is determined according to the second preset weight value and the fourth driving weight value corresponding to the average brightness value of the partition of the same backlight partition in the previous frame display picture. The control unit 204 can also store the driving weight value corresponding to the maximum brightness value of the partition and the driving weight value corresponding to the average brightness value of the partition of each backlight partition BA1 in each frame display picture, so as to compare the driving weight values ​​of a specific backlight partition BA1 in the previous and next two frames of display pictures.

[0069] The control unit 204 is used to calculate the first brightness driving value according to a first preset relationship. The first preset relationship is:

[0070] L(x) = k1 * L_max(x) + k2 * L_av(x) (1);

[0071] In the above first preset relational expression (1), L(x) is the first brightness driving value, L_max(x) is the maximum brightness value of the partition, L_av(x) is the average brightness value of the partition, k1 is the first driving weight value of the current frame display screen, and k2 is the second driving weight value of the current frame display screen. The value range of k1 is: 0 < k1 < 1, and the value range of k2 is: 0 < k2 < 1.

[0072] When the maximum brightness value of the partition and the average brightness value of the partition are determined, adjusting the magnitude of the first driving weight value and / or the second driving weight value can adjust the magnitude of the brightness driving value, and further adjust the backlight brightness of the corresponding backlight partition BA1, so as to improve the backlight accuracy of the corresponding backlight partition BA1, ensure the normal display of the details of the display screen of the corresponding backlight partition BA1, and thus improve the detail display ability of the liquid crystal display device.

[0073] The control unit 204 is further configured to calculate the magnitude of the other one of the first driving weight value and the second driving weight value based on one of the first driving weight value and the second driving weight value and a second preset relational expression. The second preset relational expression is:

[0074] k1 + k2 = 1 (2);

[0075] In the above relational expression (2), k1 is the first driving weight value and k2 is the second driving weight value.

[0076] The control unit 204 outputs a corresponding brightness driving value based on the comparison result that the preset backlight brightness values of the same backlight partition BA1 in the front and back two frames of the display screen are the same, so that the light emitting unit 201 emits light in the backlight partition based on the brightness driving value. The control unit 204 outputs a corresponding brightness driving value based on the comparison result that the preset backlight brightness values of the same backlight partition BA1 in the front and back two frames of the display screen are different, so that the light emitting unit 201 emits light in the backlight partition based on the brightness driving value.

[0077] Such as Figure 3As shown, in the liquid crystal display device 100 provided in this embodiment, the backlight module 20 may further include a storage unit 205, which is used to store the preset backlight brightness value of each backlight partition BA1 in different frames of display pictures in real time, so as to provide the preset backlight brightness value of a certain backlight partition BA1 in a certain frame of display picture to the comparison unit 203 in real time. The storage unit 205 can also be used to store the driving weight value corresponding to the maximum brightness value of the partition and the driving weight value corresponding to the average brightness value of the partition in each frame of display picture of each partition BA1 in real time, so as to provide the corresponding driving weight value of a certain backlight partition BA1 in a certain frame of display picture to the control unit 204 in real time.

[0078] The present liquid crystal display device 100 compares the preset backlight brightness value of the backlight partition BA1 in the previous frame display image with the preset backlight brightness value in the current frame display image through the comparison unit 203, so that the control unit 204 outputs a brightness driving value corresponding to the comparison result, so that the light-emitting unit 201 emits light in the corresponding backlight partition based on the brightness driving value, thereby improving the backlight brightness of the backlight partition BA1 in the dark display image, and thereby improving the detail display capability of the liquid crystal display device.

[0079] In the liquid crystal display device provided in the present application, when the comparison results of the preset backlight brightness values ​​of the same backlight partition BA1 in the previous and next two frames of display images are different, and when the first preset backlight brightness value and the second preset backlight brightness value are different, the calculation unit 202 is also used to calculate the average grayscale value of the display panel 10 in the current frame display image and the maximum backlight grayscale value of all backlight partitions BA1 in the current frame display image.

[0080] The calculation unit 202 obtains the grayscale values ​​of all pixels in all display partitions AA1 in the current frame display image, accumulates the brightness values ​​of all pixels to obtain the total grayscale value of the display panel 10, and then obtains the average grayscale value of the display panel 10 in the current frame display image according to the total grayscale value of the display panel 10 and the total number of pixels of the display panel 10.

[0081] The calculation unit 202 obtains the grayscale values ​​of all Mini-LEDs in all backlight partitions BA1 in the current frame display picture, and determines the maximum grayscale value of the Mini-LEDs in all backlight partitions BA1.

[0082] The control unit 204 is further configured to determine whether the average grayscale value of the display panel 10 in the current frame display is less than a first preset threshold and whether the maximum backlight grayscale values ​​of all backlight subareas BA1 in the current frame display are less than a second preset threshold.

[0083] If the average grayscale value of the display panel 10 in the current frame display is greater than or equal to the first preset threshold, then the average brightness of the current frame display is high, and all Mini-LEDs in the light-emitting unit 201 are turned on or only a few are turned off in the current frame display.

[0084] Therefore, there is no need to adjust the brightness of this backlight partition BA1, and there is no need to optimize the detail display capability of this backlight partition BA1 under the current frame display screen, that is, there is no need to adjust the weight value of the partition maximum brightness value and the weight value of the partition average brightness value corresponding to this backlight partition BA1. Under this judgment result, the control unit 204 determines the first preset weight value as the first driving weight value and the second preset weight value as the second driving weight value, then the first preset backlight brightness value of the backlight partition BA1 is the same as the first light-emitting driving value of this backlight partition BA1, and the light-emitting unit 201 emits light in the corresponding backlight partition BA1 based on the first preset backlight brightness value under the current frame display screen.

[0085] If the average grayscale value of the display panel 10 in the current frame display is less than the first preset threshold, but the maximum backlight grayscale values ​​of all backlight partitions BA1 in the current frame display are greater than or equal to the second preset threshold, then the average brightness of the current frame display is low and the peak brightness of the current frame display is high. In this case, there is a backlight partition BA1 with higher backlight brightness. The backlight partition BA1 produces a light diffusion phenomenon based on the higher backlight brightness, and the light diffusion phenomenon will enhance the ability to display details in the dark area around the backlight partition BA1 with higher backlight brightness.

[0086] Therefore, there is no need to adjust the brightness of the backlight partition BA1 with higher backlight brightness, and there is no need to optimize the detail display capability of the backlight partition BA1 under the current frame display screen, that is, there is no need to adjust the weight value of the partition maximum brightness value and the weight value of the partition average brightness value corresponding to the backlight partition BA1. Under this judgment result, the control unit 204 determines the first preset weight value as the first driving weight value and the second preset weight value as the second driving weight value, then the first preset backlight brightness value of the backlight partition BA1 is the same as the first light-emitting driving value of the backlight partition BA1, and the light-emitting unit 201 emits light in the corresponding backlight partition BA1 based on the first preset backlight brightness value under the current frame display screen.

[0087] If the average gray level value of the display panel 10 in the current frame display screen is less than the first preset threshold, and the maximum backlight gray level of all backlight zones BA1 in the current frame display screen is less than the second preset threshold, then the overall brightness of all backlight zones BA1 is relatively low or all Mini-LEDs of all backlight zones BA1 are in the off state. To ensure detailed display in the display zone AA1 corresponding to this backlight zone BA1, it is necessary to improve the detailed display ability of this backlight zone BA1 in this case.

[0088] Based on this judgment result, the control unit 204 is further configured to re-determine the first driving weight value of the backlight zone BA1 in the current frame display screen according to the first preset weight value and the weight adjustment value, and re-determine the second driving weight value of the same backlight zone in the current frame display screen according to the second preset weight value and the weight adjustment value.

[0089] The specific value of the weight adjustment value is determined through experimental debugging. The control unit 204 determines the first driving weight value according to the first preset weight value, the weight adjustment value determined through debugging, and the third preset relational expression. The third preset relational expression is:

[0090] ky1 + k0 = k1 (3);

[0091] In the above third preset relational expression (3), ky1 is the first preset weight value, k0 is the weight adjustment value, and k1 is the first driving weight value. Among them, the specific value range of the weight adjustment value k0 is: 0 < k0 < 1 - ky1. To improve the detailed display ability of the dark state display screen corresponding to the backlight zone BA1, it is necessary to increase the weight value corresponding to the maximum brightness value of this backlight zone. Therefore, the weight adjustment value should be greater than 0. At the same time, to avoid the halo expansion of the display screen corresponding to the over-dimming of the backlight zone BA1, the first driving weight value k1 calculated from the first preset weight value ky1 and the weight adjustment value k0 should be less than 1, that is, the weight adjustment value should not only be greater than 0 but also satisfy being less than the difference between 1 and the first preset weight value ky1.

[0092] Since the re-determined first driving weight value and the corresponding second driving weight value still need to satisfy the above second preset relational expression (2), the corresponding second driving weight value can be calculated based on the re-determined first driving weight value and the second preset relational expression (2). Then, according to the first preset relational expression (1), the re-determined first driving weight value, the corresponding second driving weight value, the average brightness value of the backlight zone, and the maximum brightness value of the backlight zone, the brightness driving value of the corresponding backlight zone in the current frame display screen is calculated.

[0093] The present liquid crystal display device 100 can also determine the size between the average grayscale value of the current frame display image and the first preset threshold value and the size between the maximum backlight grayscale value of the current frame display image and the second preset threshold value of all backlight partitions through the control unit 204. While increasing the display brightness of the backlight partition BA1 in the dark display image to improve the detail display capability of the liquid crystal display device, it can also avoid excessive dimming of the backlight partition BA1 so as to expand the halo of the corresponding display image.

[0094] like Figure 4 As shown, an embodiment of the present application further provides a backlight driving method for a liquid crystal display device. The liquid crystal display device of this embodiment includes a display panel and a backlight module. The display panel includes a plurality of display partitions, and the backlight module includes a plurality of backlight partitions corresponding to the display partitions. The backlight driving method of this embodiment includes the following steps:

[0095] S10, calculating a first preset backlight brightness value of the backlight partition corresponding to the display partition according to the average brightness value of the partition in the current frame display image and the maximum brightness value of the partition. Figure 5 As shown, step S10 may specifically include:

[0096] S101, calculating the average brightness value of the display partition in the current frame display picture. Accumulate the brightness values ​​of all pixels in the display partition to obtain the total brightness value of the display partition, and then divide the total brightness value of the display partition AA1 by the number of pixels in the display partition to obtain the average brightness value of the display partition.

[0097] S102, calculating the maximum brightness value of the display partition in the current frame display picture. Obtain the brightness values ​​of all pixels in the display partition and determine the maximum brightness value of the pixels in the display partition, and determine the maximum brightness value of the pixels in the display partition as the partition maximum brightness value.

[0098] S103, calculating a first preset backlight brightness value based on a first preset weight value corresponding to the partition maximum brightness value, a second preset weight value corresponding to the partition maximum brightness value, a partition average brightness value, and a partition maximum brightness value.

[0099] S20, comparing the second preset backlight brightness value of the backlight partition in the previous frame display picture with the first preset backlight brightness value, and outputting the comparison result, that is, comparing whether the preset backlight brightness values ​​of the same backlight partition in the previous and next frames are the same.

[0100] There are two comparison results in step S20. The first comparison result is that the second preset backlight brightness value is the same as the first preset backlight brightness value, and the second comparison result is that the second preset backlight brightness value is different from the first preset backlight brightness value.

[0101] S30, outputting a first brightness driving value of the backlight partition in the current frame display picture based on the comparison result.

[0102] The backlight driving method of the liquid crystal display device provided in the present embodiment compares the preset backlight brightness of the backlight partition in the previous frame display picture with the preset backlight brightness value of this backlight partition in the current frame display picture, and then determines the first brightness driving value of the backlight partition in the current frame display picture based on the comparison result, thereby improving the display brightness of the backlight partition in the dark state display picture to improve the detail display capability of the liquid crystal display device.

[0103] Combination Figure 4 as well as Figure 6 As shown, step S30 may specifically include step S301 and step S302.

[0104] S301 , determining a first driving weight value corresponding to a partition maximum brightness value and a second driving weight value corresponding to a partition average brightness value based on a comparison result.

[0105] Step S301 may further specifically include the following:

[0106] S3011, if the comparison result is that the second preset backlight brightness value is the same as the first preset backlight brightness value, then the third driving weight value corresponding to the maximum brightness value of this backlight partition in the previous frame display image is determined as the first driving weight value, and the fourth driving weight value corresponding to the average brightness value of the partition of this backlight partition in the previous frame display image is determined as the second driving weight value.

[0107] S3012, if the comparison result is that the second preset backlight brightness value is different from the first preset backlight brightness value, then determine whether the average grayscale value of the current frame display screen satisfies the first preset threshold and whether the maximum backlight grayscale value of all backlight partitions in the current frame display screen satisfies the second preset threshold, and determine the first driving weight value and the second driving weight value according to the judgment result.

[0108] Step S3012 may further include:

[0109] S30121: If not satisfied, the first preset weight value is determined as the first driving weight value, and the second preset weight value is determined as the second driving weight value.

[0110] S30122, if satisfied, that is, if the average gray scale value of the current frame display screen is less than the first preset threshold and the maximum backlight gray scale value of all backlight zones in the current frame display screen is less than the second preset threshold, then obtain a weight adjustment value, determine the first driving weight value according to the first preset weight value and the weight adjustment value, and determine the second driving weight value according to the second preset weight value and the weight adjustment value.

[0111] In step S30122, the first driving weight value can be determined according to the first preset weight value, the weight adjustment value, and a third preset relational expression. The third preset relational expression is:

[0112] ky1 + k0 = k1 (3);

[0113] In the above third preset relational expression (3), ky1 is the first preset weight value, k0 is the weight adjustment value, and k1 is the first driving weight value. Among them, the specific value range of the weight adjustment value k0 is: 0 < k0 < 1 - ky1.

[0114] S302, output a first brightness driving value according to the first driving weight value, the second driving weight value, the zone average brightness value, and the zone maximum brightness value.

[0115] In step S302, the first brightness driving value can be output according to a first preset relational expression, the first driving weight value, the second driving weight value, the zone average brightness value, and the zone maximum brightness value. Among them, the first preset relational expression is:

[0116] L(x) = k1 * L_max(x) + k2 * L_av(x) (1);

[0117] In the above first preset relational expression (1), L(x) is the first brightness driving value, L_max(x) is the zone maximum brightness value, L_av(x) is the zone average brightness value, k1 is the first driving weight value, and k2 is the second driving weight value. The value range of k1 is: 0 < k1 < 1, and the value range of k2 is: 0 < k2 < 1.

[0118] In step S302, the magnitude of the other of the first driving weight value and the second driving weight value can also be calculated based on one of the first driving weight value and the second driving weight value and a second preset relational expression. The second preset relational expression is:

[0119] k1 + k2 = 1 (2);

[0120] In the above relational expression (2), k1 is the first driving weight value, and k2 is the second driving weight value.

[0121] S40, control the backlight zones to emit light based on the first brightness driving value.

[0122] The backlight driving method of the liquid crystal display device provided in the present embodiment determines the size between the average grayscale value of the current frame display picture and the first preset threshold value and the size between the maximum backlight grayscale value of all backlight partitions in the current frame display picture and the second preset threshold value, and determines the first brightness driving value of the backlight partition in the current frame display picture based on the judgment result. While improving the display brightness of the backlight partition in the dark state display picture to improve the detail display capability of the liquid crystal display device, it can also avoid the problem of excessive dimming of the backlight partition resulting in the expansion of the halo of the corresponding display picture.

[0123] Of course, the present application may have many other embodiments. Without departing from the spirit and essential points of the present application, technicians familiar with the field may make various corresponding changes and modifications based on the present application, but these corresponding changes and modifications should all fall within the scope of protection of the claims attached to the present application.

Claims

1. A liquid crystal display device, characterized in that: include: A display panel, wherein the display panel includes a plurality of display partitions; A backlight module, the backlight module comprising: A light emitting unit, the light emitting unit comprising a plurality of backlight subareas corresponding to the display subareas; A calculation unit, the calculation unit is used to calculate a first preset backlight brightness value of the backlight partition corresponding to the display partition according to a partition average brightness value and a partition maximum brightness value of the display partition in a current frame display picture; A comparison unit, the comparison unit is used to compare the second preset backlight brightness value of the backlight partition in the previous frame display picture with the first preset backlight brightness value, and output a comparison result; A control unit is used to output a first brightness driving value of the backlight partition in a current frame display picture based on the comparison result, so that the light-emitting unit emits light in the backlight partition based on the first brightness driving value.

2. The liquid crystal display device according to claim 1, characterized in that: The calculation unit is used to calculate the first preset backlight brightness value based on the partition maximum brightness value, the first preset weight value corresponding to the partition maximum brightness value, the partition average brightness value and the second preset weight value corresponding to the partition average brightness value.

3. The liquid crystal display device according to claim 2, characterized in that: The control unit is used to output the first brightness driving value based on the partition maximum brightness value, the first driving weight value corresponding to the partition maximum brightness value, the partition average brightness value and the second driving weight value corresponding to the partition average brightness value, wherein the first driving weight value is determined according to the first preset weight value and the third driving weight value corresponding to the partition maximum brightness value of the backlight partition in the previous frame display image, and the second driving weight value is determined according to the second preset weight value and the fourth driving weight value corresponding to the partition average brightness value of the backlight partition in the previous frame display image.

4. The liquid crystal display device according to claim 3, characterized in that: The control unit is used to calculate the first brightness drive value according to a first preset relationship, and the first preset relationship is: L(x)=k1*L_max(x)+k2*L_av(x), wherein L(x) is the first brightness drive value, L_max(x) is the maximum brightness value of the partition, L_av(x) is the average brightness value of the partition, k1 is the first drive weight value, and k2 is the second drive weight value.

5. The liquid crystal display device according to claim 4, characterized in that: The control unit is further configured to calculate the size of the other of the first driving weight value and the second driving weight value based on one of the first driving weight value and the second driving weight value and a second preset relationship, wherein the second preset relationship is: k1+k2=1.

6. The liquid crystal display device according to claim 3, characterized in that: The control unit is used to determine the third driving weight value as the first driving weight value of the backlight partition in the current frame display picture when the comparison result is that the first preset backlight brightness value is the same as the second preset backlight brightness value, and to determine the fourth driving weight value as the second driving weight value of the backlight partition in the current frame display picture.

7. The liquid crystal display device according to claim 3, characterized in that: The control unit is used to determine whether the average grayscale value of the current frame display screen satisfies a first preset threshold and whether the maximum backlight grayscale values ​​of all the backlight partitions in the current frame display screen satisfies a second preset threshold when the comparison result is that the first preset backlight brightness value is different from the second preset backlight brightness value. If not, the first preset weight value is determined as the first driving weight value, and the second preset weight value is determined as the second driving weight value.

8. The liquid crystal display device according to claim 7, characterized in that: The calculation unit is further configured to calculate the average grayscale value of the current frame display image and the maximum backlight grayscale value of all the backlight partitions in the current frame display image when the comparison result is that the first preset backlight brightness value is different from the second preset backlight brightness value.

9. The liquid crystal display device according to claim 7, characterized in that: If satisfied, the control unit is also used to determine the first driving weight value of the backlight partition in the current frame display image according to the first preset weight value and the weight adjustment value, and to determine the second driving weight value of the backlight partition in the current frame display image according to the second preset weight value and the weight adjustment value.

10. The liquid crystal display device according to claim 9, characterized in that: The control unit is used to determine the first driving weight value of the backlight partition in the current frame display picture according to the first preset weight value, the weight adjustment value and the third preset relationship formula, and the third preset relationship formula is: ky1+k0=k1, wherein ky1 is the first preset weight value, k0 is the weight adjustment value, and k1 is the first driving weight value of the backlight partition in the current frame display picture.

11. A backlight driving method for a liquid crystal display device, the liquid crystal display device comprising a display panel and a backlight module, the display panel comprising a plurality of display partitions, the backlight module comprising a plurality of backlight partitions corresponding to the display partitions, characterized in that: The backlight driving method comprises: Calculate a first preset backlight brightness value of the backlight partition corresponding to the display partition according to a partition average brightness value and a partition maximum brightness value of the display partition in the current frame display picture; Compare the second preset backlight brightness value of the backlight partition in the previous frame display picture with the first preset backlight brightness value, and output the comparison result; Outputting a first brightness driving value of the backlight partition in a current frame display picture based on the comparison result; The backlight partitions are controlled to emit light based on the first brightness driving value.

12. The backlight driving method according to claim 11, characterized in that: The step of calculating the first preset backlight brightness value of the backlight partition corresponding to the display partition according to the average brightness value of the partition in the current frame display picture and the maximum brightness value of the partition comprises: Calculating the average brightness value of the display partition in the current frame display picture; Calculating the maximum brightness value of the display partition in the current frame display picture; The first preset backlight brightness value is calculated based on a first preset weight value corresponding to the partition maximum brightness value, a second preset weight value corresponding to the partition maximum brightness value, the partition average brightness value, and the partition maximum brightness value.

13. The backlight driving method according to claim 11, characterized in that: The step of outputting the first brightness driving value of the backlight partition in the current frame display picture based on the comparison result includes: Determine, based on the comparison result, a first driving weight value corresponding to the maximum brightness value of the partition and a second driving weight value corresponding to the average brightness value of the partition; The first brightness driving value is output according to the first driving weight value, the second driving weight value, the partition average brightness value, and the partition maximum brightness value.

14. The backlight driving method according to claim 13, characterized in that: The step of outputting the first brightness driving value according to the first driving weight value, the second driving weight value, the subarea average brightness value and the subarea maximum brightness value comprises: The first brightness driving value is output according to the first preset relationship, the first driving weight value, the second driving weight value, the partition average brightness value and the partition maximum brightness value. The first preset relationship is: L(x)=k1*L_max(x)+k2*L_av(x), wherein L(x) is the first brightness driving value, L_max(x) is the partition maximum brightness value, L_av(x) is the partition average brightness value, k1 is the first driving weight value, and k2 is the second driving weight value.

15. The backlight driving method according to claim 14, characterized in that: Also includes: The magnitude of the other of the first driving weight value and the second driving weight value is calculated based on one of the first driving weight value and the second driving weight value and a second preset relationship, wherein the second preset relationship is: k1+k2=1.

16. The backlight driving method according to claim 13, characterized in that: The step of determining the first driving weight value corresponding to the maximum brightness value of the partition and the second driving weight value corresponding to the average brightness value of the partition based on the comparison result comprises: If the comparison result is that the second preset backlight brightness value is the same as the first preset backlight brightness value, the third driving weight value corresponding to the maximum brightness value of the backlight partition in the previous frame display image is determined as the first driving weight value, and the fourth driving weight value corresponding to the average brightness value of the backlight partition in the previous frame display image is determined as the second driving weight value.

17. The backlight driving method according to claim 13, characterized in that: The step of determining the first driving weight value corresponding to the maximum brightness value of the partition and the second driving weight value corresponding to the average brightness value of the partition based on the comparison result comprises: If the comparison result is that the second preset backlight brightness value is different from the first preset backlight brightness value, determining whether the average grayscale value of the current frame display image satisfies a requirement of being less than a first preset threshold value and whether the maximum backlight grayscale values ​​of all the backlight subareas in the current frame display image satisfies a requirement of being less than a second preset threshold value; If not, the first preset weight value is determined as the first driving weight value, and the second preset weight value is determined as the second driving weight value.

18. The backlight driving method according to claim 17, characterized in that: Also includes: If satisfied, obtain the weight adjustment value; Determining the first driving weight value according to the first preset weight value and the weight adjustment value; The second driving weight value is determined according to the second preset weight value and the weight adjustment value.

19. The backlight driving method according to claim 18, characterized in that: The step of determining the first driving weight value according to the first preset weight value and the weight adjustment value comprises: The first driving weight value is determined according to the first preset weight value, the weight adjustment value and a third preset relationship, wherein the third preset relationship is: ky1+k0=k1, wherein ky1 is the first preset weight value, k0 is the weight adjustment value, and k1 is the first driving weight value.

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