Liquid crystal display apparatus, image display method, and electronic device

Abstract

A liquid crystal display apparatus, an image display method, and an electronic device, which relate to the field of display. The liquid crystal display apparatus comprises a liquid crystal display panel and a control circuit (CU). The liquid crystal display panel comprises a liquid crystal display substrate (PNL) and a backlight module (BLU). The liquid crystal display substrate (PNL) comprises a plurality of pixels. The backlight module (BLU) comprises a plurality of backlight regions (BA), and each backlight region (BA) comprises light emitting devices of n colors. The control circuit (CU) comprises a first working mode, and is configured, in the first working mode, to: receive an mth frame of initial image, and control each liquid crystal display panel to sequentially display n different sub-field images to obtain an mth frame of actual image, wherein m and n are positive integers, and n≥2. The initial image comprises initial color information of each pixel. The initial color information of one pixel comprises an initial grayscale under n tones. In one sub-field image, the backlight regions (BA) comprise a first backlight region (BA1) and a plurality of second backlight regions (BA2). The tones of light emitted by the first backlight region (BA1) and the second backlight regions (BA2) are different, and the tones of the light emitted by the second backlight regions (BA2) are the same.

Description

Liquid crystal display device, image display method, and electronic equipment

[0001] Cross-references

[0002] This disclosure claims priority to Chinese patent application number 202310707518.8 filed on June 14, 2023, entitled “LIQUID CRYSTAL DISPLAY DEVICE, IMAGE DISPLAY METHOD AND ELECTRONIC EQUIPMENT”, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present disclosure relates to the field of display technology, and in particular to a liquid crystal display device, an image display method, and an electronic device. Background Art

[0004] Display panels are an indispensable part of electronic devices such as televisions and mobile phones, among which liquid crystal display panels are widely used. However, existing liquid crystal display panels suffer from high light loss and high energy consumption during the light output process.

[0005] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present disclosure, and therefore may include information that does not constitute prior art known to ordinary technicians in the field.

[0006] Summary of the Invention

[0007] The purpose of the present disclosure is to overcome the deficiencies of the above-mentioned prior art and to provide a liquid crystal display device, an image display method and an electronic device, which can reduce the color separation phenomenon under the premise of reducing power consumption and improving resolution.

[0008] According to one aspect of the present disclosure, a liquid crystal display device is provided, comprising a liquid crystal display panel and a control circuit, wherein the liquid crystal display panel comprises a liquid crystal display substrate and a backlight module, wherein the liquid crystal display substrate comprises a plurality of pixels, and the backlight module comprises a plurality of backlight regions, each of the backlight regions comprising light-emitting devices of n colors;

[0009] The control circuit includes a first operating mode, and in the first operating mode is configured to: receive an m-th frame of initial image, control each of the liquid crystal display panels to sequentially display n different sub-field images to obtain the m-th frame of actual image; m and n are positive integers, n ≥ 2; the initial image includes initial color information of each of the pixels; the initial color information of each pixel includes initial grayscales at n tones;

[0010] In one of the sub-field images, the backlight area includes a first backlight area and a plurality of second backlight areas; the first backlight area and the second backlight area emit light of different tones; and the second backlight areas emit light of the same tones.

[0011] In an exemplary embodiment of the present disclosure, under one of the sub-field images, the backlight area includes a plurality of first backlight areas; and at least two of the first backlight areas emit light with different tones.

[0012] In an exemplary embodiment of the present disclosure, in a frame of actual image, the color reflected by the initial color information of the pixels corresponding to the first backlight area is within a first reference color gamut determined based on n first reference primary colors; the color reflected by the initial color information of the pixels corresponding to each of the second backlight areas is within a second reference color gamut determined based on n second reference primary colors;

[0013] In one of the sub-field images, the color tone of the first backlight area is the first reference primary color; and the color tone of the second backlight area is the second reference primary color.

[0014] In an exemplary embodiment of the present disclosure, based on the initial color information of each pixel in a frame of initial image, the pixels include edge pixels and color separation pixels; the color separation pixels are pixels whose brightness is greater than a brightness threshold and whose saturation is less than a saturation threshold.

[0015] In an exemplary embodiment of the present disclosure, with one backlight area as the center, a plurality of the backlight areas adjacent to the backlight area are neighboring backlight areas of the backlight area at the center; one of the neighboring backlight areas of the first backlight area is a target neighboring backlight area;

[0016] In a frame of initial image, the color feature difference between the first backlight area and the target neighborhood backlight area is not less than the color feature difference between the first backlight area and other neighborhood backlight areas; the color feature difference of the backlight area is determined based on the color feature determined by the hue of each pixel corresponding to the backlight area.

[0017] In an exemplary embodiment of the present disclosure, in a frame of initial image, the color features of any specified area satisfy the following relationship:

[0018] H1+H2=C;

[0019] C is the color feature of the designated area; H1 is the average value of the maximum T% among the hues of the pixels corresponding to the designated area; H2 is the average value of the hues of the pixels corresponding to the designated area;

[0020] The color characteristic difference between two adjacent backlight areas is the absolute value of the difference between the color characteristics of the two backlight areas.

[0021] In an exemplary embodiment of the present disclosure, n=3, an initial grayscale of the pixel in an initial image frame is (R, G, B), where R is a red grayscale, G is a green grayscale, and B is a blue grayscale;

[0022] In a frame of the initial image, the hue of a pixel corresponding to the designated area satisfies the following relationship:

[0023] h = floor(hs × 30), hs ≥ 0; or

[0024] h=hs+180,hs<0;

[0025] h is the hue of the pixel; hs is the reference hue of the pixel;

[0026] The reference hue satisfies the following relationship:

[0027] If the maximum of the initial grayscales of a pixel is the red grayscale R, then hs=(GB) / ((R-min(R, G, B));

[0028] If the maximum of the initial grayscales of a pixel is the green grayscale G, then hs=2+(BR) / ((G-min(R, G, B));

[0029] If the maximum of the initial grayscales of a pixel is the blue grayscale B, then hs=4+(RG) / (B-min(R, G, B));

[0030] min(R, G, B) is the minimum grayscale among the initial grayscales of the pixel.

[0031] In an exemplary embodiment of the present disclosure, each of the backlight areas is divided into a plurality of sub-areas along a first direction and is divided into a plurality of sub-areas along a second direction; the first direction and the second direction intersect;

[0032] In an initial image, the grayscale features of any specified area satisfy the following relationship:

[0033] Gm+Ga=Gf;

[0034] Gf is the grayscale feature of the designated area; Gm is the maximum grayscale among the grayscales of the pixels corresponding to the designated area; Ga is the average grayscale of the pixels corresponding to the designated area;

[0035] In an initial image frame, the grayscale of a pixel and its initial grayscale satisfy the following relationship:

[0036] G = k1 × R + k2 × G + k3 × B;

[0037] k1, k2 and k3 are all positive numbers;

[0038] In an initial image frame, the number of edge pixels corresponding to the first backlight area is not less than an edge threshold, and the number of color separation pixels corresponding to the first backlight area is not less than a separation threshold; and the first backlight area satisfies at least one of the following first, second, and third conditions:

[0039] The first condition is that the difference in color characteristics between the first backlight area and the target neighborhood backlight area is not greater than a first threshold;

[0040] The second condition is: a color feature difference between the first backlight area and the target neighborhood backlight area is greater than the first threshold and not greater than a second threshold; a color feature difference between the first backlight area and an adjacent sub-area in the target neighborhood backlight area is not greater than the first threshold;

[0041] The third condition is: a difference in color characteristics between the first backlight area and the target neighborhood backlight area is greater than the first threshold, and a grayscale characteristic of at least one of adjacent sub-areas between the first backlight area and the target neighborhood backlight area is not greater than the grayscale threshold;

[0042] The second backlight area does not satisfy the first condition, the second condition, and the third condition.

[0043] In an exemplary embodiment of the present disclosure, in a frame of an initial image, the number of edge pixels corresponding to the first backlight area is less than an edge threshold, and the number of color separation pixels corresponding to the first backlight area is not less than a separation threshold; and the first backlight area satisfies a fourth condition:

[0044] The fourth condition is that: the color feature difference between the first backlight area and the target neighboring backlight area is not greater than a first threshold; and the first backlight area is adjacent to at least one of the first backlight areas;

[0045] The second backlight area does not meet the fourth condition.

[0046] In an exemplary embodiment of the present disclosure, the number of color separation pixels corresponding to the first backlight area is less than a separation threshold; and the first backlight area satisfies a fifth condition:

[0047] The fifth condition is: the first backlight area is adjacent to at least one of the first backlight areas;

[0048] The second backlight area does not meet the fifth condition.

[0049] In an exemplary embodiment of the present disclosure, the control circuit further includes a second operating mode, and in the second operating mode is configured to: receive an m-th frame initial image, and control the liquid crystal display device to sequentially display n subfield images according to the initial color information of each pixel to obtain an m-th frame image;

[0050] In a subfield image of the second operating mode, light-emitting devices of the same color in each backlight area emit light.

[0051] In an exemplary embodiment of the present disclosure, the liquid crystal display substrate includes:

[0052] An array substrate and a counter substrate arranged opposite to each other;

[0053] a liquid crystal layer, disposed between the array substrate and the counter substrate;

[0054] The control circuit is connected to the array substrate and the backlight module.

[0055] According to one aspect of the present disclosure, there is provided an image display method for a liquid crystal display device, the liquid crystal display device comprising a liquid crystal display panel and a control circuit, the liquid crystal display panel comprising a liquid crystal display substrate and a backlight module, the liquid crystal display substrate comprising a plurality of pixels, the backlight module comprising a plurality of backlight regions, each of the backlight regions comprising light-emitting devices of n colors; the image display method comprising:

[0056] In the first working mode:

[0057] Receive an m-th frame of an initial image, wherein the initial image includes initial color information of each pixel; the initial color information of each pixel includes initial grayscales at n tones; m and n are positive integers, and n≥2;

[0058] determining the actual color tone of each of the backlight areas under n sub-field images according to the initial color information;

[0059] Controlling each of the backlight areas to emit light according to the actual color tone, and controlling the pixels according to the initial grayscale to sequentially display n different subfield images to obtain the mth frame actual image;

[0060] In one of the sub-field images, the backlight area includes a first backlight area and a plurality of second backlight areas; the actual hues of light emitted by the first backlight area and the second backlight area are different; and the actual hues of light emitted by each of the second backlight areas are the same.

[0061] In an exemplary embodiment of the present disclosure, determining the actual color tone of each backlight area under n sub-field images according to the initial color information includes:

[0062] determining edge pixels in the initial image according to the initial color information;

[0063] determining the hue, saturation, and brightness of each pixel according to the initial color information;

[0064] Determining the color characteristics and grayscale characteristics of the color separation pixel and each of the backlight areas according to the hue, saturation and brightness of each of the pixels; the color separation pixel is a pixel having a brightness greater than a brightness threshold and a saturation less than a saturation threshold;

[0065] Dividing each of the backlight areas into at least a first backlight area and a second backlight area according to the color characteristics and grayscale characteristics of the backlight area;

[0066] Establishing a first reference color gamut according to the color reflected by the initial color information of the pixels corresponding to the first backlight area, and determining n first reference primary colors according to the first reference color gamut;

[0067] Establishing a second reference color gamut according to the colors reflected by the initial color information of the pixels corresponding to each of the second backlight areas, and determining n second reference primary colors according to the second reference color gamut;

[0068] Controlling each of the backlight areas to emit light according to the actual color tone; comprising:

[0069] In one of the sub-field images, the actual hue of light emitted from the first backlight area is controlled to be the first reference primary color; and the actual hue of light emitted from the second backlight area is controlled to be the second reference primary color.

[0070] In an exemplary embodiment of the present disclosure, determining edge pixels in the initial image according to the initial color information includes:

[0071] Gray-scaling the initial image to obtain the grayscale of each pixel;

[0072] Determining the gradient magnitude and gradient direction of each pixel according to the grayscale of each pixel;

[0073] An edge pixel among the pixels is determined according to the gradient magnitude and gradient direction of the pixels.

[0074] In an exemplary embodiment of the present disclosure, n=3, an initial grayscale of the pixel in an initial image frame is (R, G, B), where R is a red grayscale, G is a green grayscale, and B is a blue grayscale;

[0075] In a frame of initial image, the hue of a pixel satisfies the following relationship:

[0076] h = floor(hs × 30), hs ≥ 0; or

[0077] h=hs+180,hs<0;

[0078] h is the hue of the pixel; hs is the reference hue of the pixel;

[0079] The reference hue satisfies the following relationship:

[0080] If the maximum of the initial grayscales of a pixel is the red grayscale R, then hs=(GB) / ((R-min(R, G, B));

[0081] If the maximum of the initial grayscales of a pixel is the green grayscale G, then hs=2+(BR) / ((G-min(R, G, B));

[0082] If the maximum of the initial grayscales of a pixel is the blue grayscale B, then hs=4+(RG) / (B-min(R, G, B));

[0083] min(R, G, B) is the minimum grayscale among the initial grayscales of the pixel;

[0084] The saturation of the pixel satisfies the following relationship:

[0085] S = 1-W / max(R, G, B);

[0086] S is the saturation of the pixel; W is the second largest grayscale among the initial grayscales of the pixel; max(R, G, B) is the largest grayscale among the initial grayscales of the pixel;

[0087] The brightness of the pixel is the maximum gray level among its initial gray levels.

[0088] In an exemplary embodiment of the present disclosure, the color separation pixel is a pixel having a brightness less than a brightness threshold and a saturation greater than a saturation threshold;

[0089] In an initial image, the color features of any specified area satisfy the following relationship:

[0090] H1+H2=C;

[0091] C is the color feature of the designated area; H1 is the average value of the maximum T% among the hues of the pixels corresponding to the designated area; H2 is the average value of the hues of the pixels corresponding to the designated area;

[0092] The color characteristic difference between two adjacent backlight areas is the absolute value of the difference between the color characteristics of the two backlight areas;

[0093] In an initial image, the grayscale features of any specified area satisfy the following relationship:

[0094] Gm+Ga=Gf;

[0095] Gf is the grayscale feature of the designated area; Gm is the maximum grayscale among the grayscales of the pixels corresponding to the designated area; Ga is the average grayscale of the pixels corresponding to the designated area;

[0096] In an initial image frame, the grayscale of a pixel and its initial grayscale satisfy the following relationship:

[0097] G = k1 × R + k2 × G + k3 × B;

[0098] k1, k2 and k3 are all positive numbers.

[0099] In an exemplary embodiment of the present disclosure, each backlight area is divided into at least a first backlight area and a second backlight area according to the color characteristics and grayscale characteristics of the backlight area; comprising:

[0100] Dividing each of the backlight areas into a plurality of sub-areas along a first direction and into a plurality of sub-areas along a second direction; wherein the first direction and the second direction intersect;

[0101] Selecting one backlight area as a first backlight area to be divided from the backlight areas in which the number of the edge pixels is not less than the edge threshold and the number of the color separation pixels is not less than the separation threshold;

[0102] Taking the first backlight area to be divided as the center, determining the color feature differences and grayscale feature differences between the first backlight area and its adjacent neighborhood backlight areas; and taking the neighborhood backlight area with the largest color feature difference as the target neighborhood backlight area;

[0103] Determining a difference in color characteristics between the first backlight area to be divided and adjacent sub-areas in the target neighborhood backlight area;

[0104] If the color feature difference between the first backlight area to be divided and the target neighborhood backlight area is not greater than a first threshold, the first condition is met and the first backlight area to be divided is the first backlight area;

[0105] If the color feature difference between the first backlight area and the target neighboring backlight area is greater than the first threshold and not greater than the second threshold; and the color feature difference between the first backlight area to be divided and the adjacent sub-area in the target neighboring backlight area is not greater than the first threshold; then the second condition is met and the first backlight area to be divided is the first backlight area;

[0106] If the difference in color characteristics between the first backlight area and the target neighboring backlight area is greater than the first threshold, and the grayscale characteristic of at least one of the adjacent sub-areas between the first backlight area and the target neighboring backlight area is not greater than the grayscale threshold, then the third condition is met and the first backlight area to be divided is the first backlight area;

[0107] If the first condition, the second condition, and the third condition are not satisfied, the first backlight area to be divided is the second backlight area.

[0108] In an exemplary embodiment of the present disclosure, each of the backlight areas is divided into at least a first backlight area and a second backlight area according to the color characteristics and grayscale characteristics of the backlight area; further comprising:

[0109] Select one backlight area as a second backlight area to be divided from the backlight areas in which the number of edge pixels corresponding to the first backlight area is less than the edge threshold and the number of color separation pixels corresponding to the first backlight area is not less than the separation threshold;

[0110] If the color characteristic difference between the second backlight area to be divided and the target neighboring backlight area is not greater than the first threshold; and at least one of the neighboring backlight areas of the second backlight area to be divided is the first backlight area, then the fourth condition is met and the second backlight area to be divided is the first backlight area; if the fourth condition is not met, the second backlight area to be divided is the second backlight area.

[0111] In an exemplary embodiment of the present disclosure, each of the backlight areas is divided into at least a first backlight area and a second backlight area according to the color characteristics and grayscale characteristics of the backlight area; further comprising:

[0112] Selecting one from the backlight areas where the number of color separation pixels is less than the separation threshold as a third backlight area to be divided;

[0113] If the third backlight area to be divided is adjacent to at least one of the first backlight areas, the fifth condition is met and the third backlight area to be divided is the first backlight area; if the fifth condition is not met, the third backlight area to be divided is the second backlight area.

[0114] According to one aspect of the present disclosure, an electronic device is provided, comprising any one of the above-mentioned liquid crystal display devices.

[0115] The liquid crystal display device, image display method, and electronic device disclosed herein can achieve field sequential display by temporally mixing the colors of n sub-field images displayed successively, without adopting a spatial color mixing method and without setting a color filter, which can improve light extraction efficiency and eliminate the need to set sub-pixels of different colors, thereby improving resolution.

[0116] Furthermore, in the first operating mode, within a subfield image, the first and second backlight areas emit light with different hues, allowing different areas of the subfield image to use different primary colors, rather than the same primary color. In this process, since the first and second backlight areas are local to the liquid crystal display panel, the color gamut determined by the colors of their corresponding pixels is smaller than the color gamut determined by the colors of all pixels. This results in a smaller difference in primary colors between the first and second backlight areas within different subfield images than the difference in primary colors within different subfield images determined based on the colors of all pixels. This reduction in primary color differences can mitigate color separation. Thus, by determining primary colors based on backlight areas rather than across the entire liquid crystal display panel, primary color differences can be reduced, thereby improving color separation.

[0117] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0118] The accompanying drawings are incorporated into and constitute a part of the specification, illustrate embodiments consistent with the present disclosure, and together with the specification, are used to explain the principles of the present disclosure. Obviously, the drawings described below are only some embodiments of the present disclosure, and those skilled in the art can derive other drawings based on these drawings without inventive effort.

[0119] FIG1 is a schematic structural diagram of an embodiment of a liquid crystal display device disclosed herein.

[0120] FIG2 is a circuit diagram of an embodiment of a liquid crystal display device disclosed herein.

[0121] FIG3 is a partial schematic diagram of the mth frame image of the liquid crystal display device of the present disclosure in the first working mode.

[0122] 4 to 6 are principle diagrams of three subfield images of the m-th frame image in FIG. 3 .

[0123] FIG7 is a schematic diagram of an embodiment of an electronic device disclosed herein.

[0124] FIG8 is a flowchart of the image processing method disclosed herein.

[0125] FIG9 is a schematic diagram of a first backlight area and a second backlight area in the liquid crystal display device of the present disclosure.

[0126] FIG. 10 is a schematic diagram of a first backlight region and its neighboring backlight regions in the liquid crystal display device of the present disclosure. DETAILED DESCRIPTION

[0127] Example embodiments will now be described more fully with reference to the accompanying drawings. However, the example embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete and will fully convey the concepts of the example embodiments to those skilled in the art. Like reference numerals in the figures represent identical or similar structures, and thus their detailed descriptions will be omitted. Furthermore, the figures are merely schematic illustrations of the present disclosure and are not necessarily drawn to scale.

[0128] The terms "a", "an", "the", "said" and "at least one" are used to indicate the presence of one or more elements / components / etc.; the terms "including" and "having" are used to express open-ended inclusion and mean that additional elements / components / etc. may be present in addition to the listed elements / components / etc.; the terms "first", "second" and "third" etc. are used only as labels and are not intended to limit the quantity of their objects.

[0129] The present disclosure provides a liquid crystal display device, as shown in FIG1 and FIG2 . The liquid crystal display device may include a liquid crystal display panel and a control circuit CU, wherein:

[0130] A liquid crystal display panel has a plurality of pixels arranged in an array. A pixel is the smallest display unit. The liquid crystal display panel may include a liquid crystal display substrate (PNL) and a backlight unit (BLU). The liquid crystal display substrate (PNL) may include an array substrate (TB) and a counter substrate (FB) disposed opposite each other, and may further include a liquid crystal layer (LL) disposed between the array substrate (TB) and the counter substrate (FB).

[0131] The liquid crystal display substrate PNL also includes pixel electrodes and common electrodes. The pixel electrodes can be provided on the array substrate TB, while the common electrodes can be provided on the array substrate TB or the counter substrate FB. Each pixel can include a pixel electrode and its corresponding liquid crystal layer LL. The array substrate TB includes a drive circuit. The control circuit CU can be provided on the array substrate TB. The drive circuit controls the voltage between the pixel electrode and the common electrode, thereby controlling the degree of deflection of the liquid crystal molecules in the liquid crystal layer LL. This in turn controls the light transmittance of each pixel, thereby adjusting the grayscale of each pixel.

[0132] The backlight module BLU may be disposed on a side of the array substrate TB away from the counter substrate FB. The backlight module BLU may emit light toward the array substrate TB under the control of the control circuit CU.

[0133] In some embodiments, the counter substrate (FB) may include a color filter layer comprising multiple filter sections. Each pixel may include one filter section. Through the filtering effect of the filter sections, each pixel emits monochromatic light, and different pixels can emit different colors. However, the color filter layer causes significant light loss, reducing the brightness of the LCD device without increasing the power of the backlight unit (BLU). Increasing the brightness requires increasing the power of the backlight unit (BLU), resulting in increased power consumption.

[0134] In order to improve the light extraction efficiency without increasing power consumption, in some embodiments, the counter substrate FB may not be provided with a color filter layer to reduce light loss, which is conducive to improving the light extraction efficiency. In order to achieve color display, the backlight module BLU can include light-emitting devices of n different colors. The number of light-emitting devices of the same color is not specifically limited here, and the number of light-emitting devices of each color is multiple. The color of the light emitted by the backlight module BLU is the hue of the picture. The light emitted by the backlight module BLU can be used as a light source to display the image, and the pixel can control the deflection state of the liquid crystal, thereby controlling the grayscale of the pixel. The image display is achieved through the cooperation of the backlight module BLU and the pixel.

[0135] On this basis, field sequential display can be used when displaying images. For example, n subfield images are displayed in sequence within one frame. The colors of different subfield images can be different. In each subfield image, the grayscales of different pixels can be different, and the grayscales of the same pixel in different subfield images can be different.

[0136] The color of a sub-field image can be limited by the color of light emitted by the backlight module (BLU). For example, in some embodiments, when displaying the same sub-field image, only light-emitting devices of one color in the backlight module (BLU) emit light during each sub-field image display, so that each sub-field image has only one hue, that is, one color. This allows for a single frame of image to be obtained based on the persistence of vision phenomenon.

[0137] In some embodiments, the backlight module (BLU) can be divided into multiple backlight areas (BAs), each of which has light-emitting devices (LEDs) of n colors, each of which can be independently controlled. A backlight area (BA) can correspond to multiple pixels, meaning that the orthographic projections of multiple pixels on the backlight module (BLU) are located within a single backlight area (BA). The brightness of the light-emitting devices in different backlight areas (BAs) can vary, enabling different brightness levels across the BAs and enabling control of the BAs.

[0138] As shown in FIG2 , in some embodiments of the present disclosure, the control circuit CU may be configured to execute one or more operating modes, including a first operating mode. In the first operating mode:

[0139] The control circuit CU is configured to receive initial color information of each pixel of the mth frame initial image and control the brightness of each backlight area BA and the grayscale of the pixels based on the initial color information, thereby sequentially displaying n subfield images of different tones to obtain the mth frame actual image. m and n are positive integers, and n ≥ 2.

[0140] The initial color information for each pixel may include initial grayscales in n tones. For a pixel in an initial image frame, the n grayscales can be displayed sequentially, achieving temporal color mixing, so that the pixel presents the desired color. For example, if n = 3, and the three tones are red, green, and blue, the initial color information for each pixel in the mth frame of the image may include an initial grayscale for red, an initial grayscale for green, and an initial grayscale for blue.

[0141] The n tones represent the n primary colors of the actual image in the mth frame, meaning the actual image in the mth frame is a mixture of n primary colors. In a field sequence, each backlight area BA of the backlight unit (BLU) emits the same hue, with only light-emitting devices of the same color emitting light. The brightness of different backlight areas BA can be varied, which can be achieved by controlling the power of the light-emitting devices in each backlight area BA or by controlling the number of light-emitting devices actually emitting light.

[0142] After receiving the mth initial image, the color gamut of the mth initial image can be determined based on the colors reflected by the initial color information of all pixels. Based on this color gamut, n primary colors, or n hues, can be determined. Within the same subfield image, each backlight area BA has the same hue. For example, in the RGB color space, the color gamut can be represented by a color gamut triangle encompassing the colors of all pixels in the mth initial image. The three vertices of this triangle can serve as the three primary colors. Based on this, within each subfield image, only one light-emitting device of one color emits light in each backlight area BA.

[0143] Figures 4 through 6 illustrate three subfield images. In different subfield images, the illuminated pixels P form multiple stripe patterns. The illuminated pixels in different subfield images can differ or overlap, meaning the same pixel can illuminate in each subfield image. The three subfield images form the mth frame image shown in Figure 3. It should be noted that Figure 3 is intended only to illustrate the principle of color mixing and the resulting visual effect of the three subfield images and does not limit the specific patterns of the subfield images.

[0144] In one embodiment, the backlight unit (BLU) may include three types of light-emitting devices, each capable of emitting red, green, and blue light. A single frame of image can be divided into three sub-field images, each with a red, green, and blue hue. These three sub-field images are displayed sequentially to visually form a single frame of image.

[0145] As shown in Figure 2 , the control circuit CU can be connected to the array substrate TB and the backlight module BLU to control the backlight module BLU's light emission and the degree of liquid crystal deflection, that is, to control the color and grayscale of each pixel. The control circuit CU may include a timing controller, a gate drive circuit, a source drive circuit, a backlight control circuit, etc., and its structure is not particularly limited here.

[0146] The inventors discovered that when using field-sequential display, because a single actual image frame is composed of a color mix of multiple sub-field images displayed at different times, users may observe red, green, and blue tones simultaneously in the image when blinking, scanning, or when an object in the image moves, resulting in color separation. Furthermore, in each sub-field image, only one color of the light-emitting device emits light, resulting in the highest saturation of the primary color in each backlight area BA. This results in greater differences between the primary colors, making the aforementioned color separation phenomenon more pronounced.

[0147] The inventors have discovered through research that the primary colors can be determined independently by the area corresponding to at least a portion of the backlight area BA of the backlight module BLU, thereby reducing the saturation of the primary colors and thus weakening the color separation phenomenon. The following is an exemplary explanation:

[0148] In the first working mode, the control circuit CU may be configured to execute an image display method. As shown in FIG8 , the image display method may include steps S10 to S30, wherein:

[0149] Step S10: receiving initial color information of the mth frame of the initial image, where the initial color information of each pixel includes initial grayscales in n tones; m and n are positive integers, and n≥2;

[0150] Step S20: determining the actual color tone of each backlight area BA under n sub-field images according to the initial color information;

[0151] Step S30 : Control each backlight area BA to emit light according to the actual color tone, and control the pixels according to the initial grayscale to sequentially display n different sub-field images to obtain the mth frame actual image.

[0152] As shown in Figure 9, under a subfield image, the backlight area BA includes a first backlight area BA1 and multiple second backlight areas BA2. By implementing the image display method disclosed herein, the first backlight area BA1 and the second backlight area BA2 can emit light with different hues; and the second backlight areas BA2 can emit light with the same hue. The areas corresponding to different backlight areas BA (the first backlight area BA1 and the second backlight area BA2) of the subfield image can use different primary colors instead of the same primary color. In this process, the first backlight area BA1 and the second backlight area BA2 are local parts of the liquid crystal display panel, and the color gamut determined by the colors of the pixels corresponding to them is smaller than the color gamut determined by the colors of all pixels. This makes the difference between the primary colors of the first backlight area BA1 and the second backlight area BA2 under different subfield images smaller than the difference in primary colors under different subfield images determined based on the colors of all pixels. The reduction in the difference in primary colors can weaken the color separation phenomenon.

[0153] The image display method is described in detail below:

[0154] In step S10, any frame of the initial image may include the initial color information of each pixel, and the initial color information of each pixel in the frame of the initial image includes initial grayscales in n different tones. n can be a positive integer greater than or equal to 2, for example, n=3, and the three tones are red, green, and blue respectively; the initial grayscale of a pixel may include an initial grayscale R of red, an initial grayscale G of green, and an initial grayscale B of blue, and the initial grayscale of the pixel may be expressed as (R, G, B). Any initial grayscale may be any integer between 0 and 255. The initial image is not the image actually displayed by the liquid crystal display panel, but a collection of initial color information of each pixel.

[0155] In step S20, the actual hue of each backlight area BA under n subfield images can be derived based on the initial color information of each pixel in the mth frame of the initial image. Within the same subfield image, the actual hues of different backlight areas BA can be the same or different. A backlight area BA has light-emitting devices of n different colors. The actual hue of the backlight area BA is formed by the color mixing of light emitted by the light-emitting devices that actually emit light. For example, if only red light-emitting devices in a backlight area BA are emitting light, its actual hue is red. However, if all red light-emitting devices and some green light-emitting devices in a backlight area BA are emitting light, the actual hue is no longer red but rather yellowish, resulting in a mixed color of another color. The actual hue can be controlled by controlling the number of light-emitting devices that actually emit light. The actual hue is the primary color of the backlight area BA when displaying the mth frame of the image, that is, the color of the backlight area BA when displaying a field sequence.

[0156] For a backlight area BA, a color gamut range can be determined based on the colors reflected by the initial color information of its corresponding pixels, and a primary color can be determined based on this color gamut range, thereby determining the actual hue of the backlight area BA. Alternatively, multiple backlight areas BA can be treated as a whole, and a color gamut range can be determined based on the colors reflected by the initial color information of the pixels corresponding to the multiple backlight areas BA, and a primary color can be determined based on this color gamut range, thereby simultaneously determining the actual hues of the multiple backlight areas BA. The actual hues of these backlight areas BA in the same field-sequential image are the same.

[0157] If the actual hue is determined independently for each backlight area BA, the actual hues of different backlight areas BA may differ. The diffusion of light within the backlight areas BA will cause crosstalk between adjacent backlight areas BA, resulting in color shift. The color shift is particularly noticeable for backlight areas BA with large contrast in actual hue. To reduce the degree of color shift while improving separation, the backlight areas BA can be dynamically classified based on the initial color information of each initial image frame, dividing them into at least a first backlight area BA1 and a second backlight area BA2. The actual hue is determined individually for the first backlight area BA1, while the actual hue can be determined for the multiple second backlight areas BA2 as a whole. This is explained in detail below:

[0158] In some embodiments of the present disclosure, step S20 may include steps S210 to S240, wherein:

[0159] Step S210: Determine edge pixels in the initial image according to the initial color information.

[0160] For an initial image frame, edge detection can be performed on it according to an edge detection algorithm to determine edge pixels in the initial image frame. For example, Canny edge detection or other methods can be used to perform edge detection.

[0161] In some embodiments of the present disclosure, for a frame of initial image, step S210 may include steps S2110 to S2140, wherein:

[0162] Step S2110: grayscale the initial image to obtain the grayscale of each pixel.

[0163] Taking n=3 and the initial grayscale of each pixel as (R, G, B) above as an example, in an initial image frame, the grayscale of a pixel and its initial grayscale satisfy the following relationship:

[0164] G = k1 × R + k2 × G + k3 × B;

[0165] G is the pixel's grayscale, R is the initial grayscale of red, G is the initial grayscale of blue, and B is the initial grayscale of blue. k1, k2, and k3 are all positive numbers. Because the human eye is more sensitive to green than red, and more sensitive to red than blue, for example, k1 can be 0.3, k2 can be 0.59, and k3 can be 0.11.

[0166] Step S2120: filter the grayscale of each pixel.

[0167] The smoothness of the grayscale of each pixel can be improved by filtering. The filtering method can be Gaussian filtering, which is not specifically limited here. For example, a filter template is used to scan each pixel one by one, and the scanned pixel is the pixel located at the center of the filter template. The range of the filter template may include multiple pixels. For example, the filter template may include 3×3 pixels or 5×5 pixels. The average value or weighted average value of the grayscale of the pixels within the range of the filter template is used as the new grayscale of the pixel at the center of the filter template, but the new grayscale does not participate in the calculation of the new grayscale of other pixels, that is, the grayscale obtained in step S2110 is used when calculating the new grayscale during the filtering process.

[0168] Step S2130: Determine the gradient magnitude and gradient direction of each pixel according to the grayscale of each pixel.

[0169] Let (i, j) be the coordinates of a pixel in a coordinate system, and G(i, j) be the grayscale of the pixel located at (i, j).

[0170] The horizontal gradient of the pixel is: G_x = (G(i-1, j-1) + 2×G(i-1, j) + G(i-1, j+1)) - (G(i+1, j-1) + 2×G(i+1, j) + G(i+1, j+1)).

[0171] The vertical gradient of the pixel is: G_y = (G(i-1, j-1) + 2×G(i, j-1) + G(i+1, j-1)) - (G(i-1, j+1) + 2×G(i, j+1) + G(i+1, j+1)).

[0172] The corresponding gradient magnitude of the pixel is: G = |G_x| + |G_y|.

[0173] The gradient direction is: θ = arctan(G_x / G_y).

[0174] Step S2140: Determine edge pixels among the pixels based on the gradient magnitude and gradient direction of each pixel.

[0175] In an initial image frame, whether a pixel is an edge pixel can be determined by the following method:

[0176] Compare the gradient magnitude of the pixel with the gradient magnitudes of the two pixels before and after it in the gradient direction. If the gradient magnitude of the pixel is not the largest, the gradient magnitude of the pixel position can be set to 0, and the pixel is not an edge pixel.

[0177] If the gradient magnitude of the pixel exceeds the high gradient threshold, the pixel is an edge pixel. If the initial image is displayed, the pixel is an edge point. If the gradient magnitude of the pixel is lower than the low gradient threshold, the pixel is not an edge pixel. The high gradient threshold is greater than the low gradient threshold.

[0178] If the gradient magnitude of the pixel is between the high gradient threshold and the low gradient threshold, it can be determined whether there is a pixel with a gradient magnitude greater than the high gradient threshold among the 3×3 pixels adjacent to the pixel. If so, the pixel is an edge pixel, otherwise it is not an edge pixel.

[0179] Of course, in other embodiments of the present disclosure, the above filtering may also be performed, that is, step S2120 is not included, and the grayscale in step S2110 is used to perform step S2130.

[0180] In the initial image, the region of edge pixels is located in a region with a large color contrast. Therefore, the more edge pixels there are in a region, the more obvious the color separation phenomenon is.

[0181] Step S220: Determine the hue, saturation, and brightness of each pixel according to the initial color information.

[0182] Take n=3 and the initial grayscale of a pixel in an initial image frame as (R, G, B) as an example:

[0183] In a frame of initial image, the hue of a pixel satisfies the following relationship:

[0184] h = floor(hs × 30), hs ≥ 0; or

[0185] h=hs+180,hs<0;

[0186] h is the hue of a pixel; hs is the reference hue of a pixel; floor means rounding down. Specifically, if hs×30 is an integer, then h=hs. If hs×30 is not an integer, then h is the largest integer less than hs×30.

[0187] The reference hue hs can satisfy the following relationship:

[0188] If the maximum initial grayscale of a pixel is the red grayscale R, then hs = (GB) / ((R-min(R, G, B));

[0189] If the maximum initial grayscale of a pixel is the green grayscale G, then hs = 2 + (BR) / ((G - min (R, G, B));

[0190] If the maximum initial grayscale of a pixel is the blue grayscale B, then hs = 4 + (RG) / (B - min (R, G, B));

[0191] min(R, G, B) is the minimum grayscale among the initial grayscales of a pixel.

[0192] The saturation of a pixel satisfies the following relationship:

[0193] S = 1-W / max(R, G, B);

[0194] S is the saturation of the pixel; W is the second largest grayscale among the initial grayscales of a pixel, that is, the second one when the initial grayscales are sorted from large to small; max(R, G, B) is the largest grayscale among the initial grayscales of a pixel;

[0195] The brightness V of a pixel may be the maximum grayscale max(R, G, B) among its initial grayscales. Of course, the brightness V may also be the average value or weighted average value of its initial grayscales.

[0196] In the initial image, the degree of color separation is positively correlated with brightness and negatively correlated with saturation. For a region, the more pixels have brightness greater than the brightness threshold tv and saturation less than the saturation threshold ts, the more obvious the color separation is in the region.

[0197] Step S230: Determine the color characteristics and grayscale characteristics of the color separation pixels and each backlight area BA according to the hue, saturation and brightness of each pixel; the color separation pixels are pixels with brightness greater than the brightness threshold and saturation less than the saturation threshold.

[0198] In a frame of initial image, a designated area can be arbitrarily divided, and the color features and grayscale features of the designated area can be calculated. The designated area includes multiple pixels, but the size is not limited. Its range can be the same as the size of the backlight area BA, or it can be the same size or smaller than the backlight area BA.

[0199] In some embodiments of the present disclosure, based on the embodiment of step S220 above, the color characteristics of the designated area satisfy the following relationship:

[0200] H1+H2=C;

[0201] C is the color feature of the specified area; H1 is the average value of the largest T% among the hues of the pixels corresponding to the specified area, that is, the hues of the pixels in the specified area are sorted, and the first T% is selected to calculate the average value. T can be equal to 5, of course, or 3, 7, etc.; H2 is the average value of the hues of the pixels corresponding to the specified area;

[0202] In an initial image, the grayscale features of any specified area satisfy the following relationship:

[0203] Gm+Ga=Gf;

[0204] Gf is the grayscale feature of the specified area; Gm is the maximum grayscale among the grayscales of each pixel corresponding to the specified area; Ga is the average grayscale of each pixel corresponding to the specified area.

[0205] Through the above relationship, the color features and grayscale features of any area can be calculated. For example, the color features and grayscale features of each backlight area BA can be calculated. In addition, the backlight area BA can be further divided into multiple sub-areas along the first direction X, for example, into two or three sub-areas along the first direction X. At the same time, the backlight area BA can also be divided into multiple sub-areas along the second direction Y, for example, into two or three sub-areas along the second direction Y. The sub-areas divided along the first direction X and the sub-areas divided along the second direction Y may overlap. The first direction X and the second direction Y are directions that intersect each other. For example, the first direction X and the second direction Y are perpendicular. As shown in Figures 9 and 10, the first direction X is the horizontal direction in the figure, and the second direction Y is the vertical direction in the figure.

[0206] Furthermore, based on the color characteristics of two adjacent designated areas, the color characteristic difference between the two adjacent designated areas can be calculated. This difference can be the absolute value of the difference between the color characteristics of the two sub-areas. Accordingly, if the designated area is a backlight area BA, the color characteristic difference between the two adjacent backlight areas BA is the absolute value of the difference between the color characteristics of the two backlight areas BA. If the designated area is a sub-area, the color characteristic difference between the two adjacent sub-areas is the absolute value of the difference between the color characteristics of the two sub-areas.

[0207] Step S240 : Divide each backlight area BA into at least a first backlight area BA1 and a second backlight area BA2 according to the color characteristics and grayscale characteristics of the backlight area BA.

[0208] The first backlight area BA1 and the second backlight area BA2 are classifications of backlight areas BA, rather than specific backlight areas BA. For any backlight area BA in an initial image, the number of edge pixels and color separation pixels corresponding to that backlight area BA can be determined according to steps 210-230. The more edge pixels, the more likely color separation will occur, and the more color separation pixels, the more pronounced the color separation will be.

[0209] The number of color-separated pixels can be classified into two cases: less than the separation threshold and not less than the separation threshold. If the number of color-separated pixels is less than the separation threshold, it can be further classified into two cases: the number of edge pixels is greater than the edge threshold or not greater than the edge threshold. For example, the edge threshold can be 70 and the separation threshold can be 200.

[0210] In some embodiments of the present disclosure, a backlight area BA having a number of color separation pixels not less than a separation threshold and a number of edge pixels not less than an edge threshold may be defined as a first backlight area to be divided. The first backlight area to be divided may be divided into the first backlight area BA1 or the second backlight area BA2 based on the difference in color characteristics and grayscale characteristics. Detailed description is provided below:

[0211] The color feature differences between the first backlight area to be divided and the neighboring backlight area BA adjacent to it can be calculated respectively, and the neighboring backlight area BA with the largest color feature difference can be selected as the target neighboring backlight area BA. At the same time, the grayscale features of each backlight area BA and the sub-area of ​​each backlight area BA can be calculated. Among them, the field backlight area BA refers to a plurality of backlight areas BA adjacent to the first backlight area to be divided, that is, the first backlight area to be divided is used for the neighboring backlight area BA and there are no other backlight areas BA between them. The number of neighboring backlight areas BA of the first backlight area to be divided can be 8, that is, the first backlight area to be divided and its neighboring backlight area BA are distributed 3×3 along the first direction X and the second direction Y, and the first backlight area to be divided is located at the center.

[0212] If the color characteristic difference between the first backlight area to be divided and the target neighboring backlight area BA is no greater than a first threshold, i.e., greater than or equal to the first threshold (for example, the first threshold may be 6), the first condition is considered to be met, and the first backlight area to be divided may be divided into the first backlight area BA1. Furthermore, if the grayscale characteristic of a neighboring backlight area BA is no greater than the grayscale threshold, the color characteristic difference between the first backlight area to be divided and the neighboring backlight area BA may be set to 0.

[0213] If the color feature difference between the first backlight area BA1 and the target neighborhood backlight area BA is greater than the first threshold, the color feature difference can be further compared with the second threshold, and the second threshold is greater than the first threshold, for example, the second threshold is 50; and when it is less than or equal to the second threshold, that is, not greater than the second threshold, the color feature difference between the first backlight area to be divided and the two adjacent sub-areas in the target neighborhood backlight area BA is further compared, and the grayscale of the two sub-areas is compared with the grayscale threshold respectively; if the color feature difference between the first backlight area to be divided and the two adjacent sub-areas in the target neighborhood backlight area BA is not greater than the first threshold, it is deemed to meet the second condition; at the same time, if the grayscale features of the two sub-areas are both not greater than the grayscale threshold; it can be deemed to meet the third condition, and the first backlight area to be divided can be divided into the first backlight area BA1.

[0214] In addition, in order to facilitate the determination of the comparison results of the grayscale features and the grayscale threshold, when the grayscale features of the two adjacent sub-areas mentioned above are not greater than and not greater than the grayscale threshold, they can be recorded separately using the grayscale flag bit. For example, when the grayscale feature is not greater than the grayscale threshold, the grayscale flag bit is set to 0, and when the grayscale feature is greater than the grayscale threshold, the grayscale flag bit is set to 1.

[0215] For example, Figure 10 shows a first backlight area to be divided and its neighboring backlight areas BA. There are eight neighboring backlight areas BA, located above, below, on the left, and right sides, as well as on the upper left, upper right, lower left, and lower right sides. Each backlight area BA is divided into three sub-areas along the first direction X and the second direction Y: left, center, and right sub-areas in the first direction X, and top, center, and bottom sub-areas in the second direction Y.

[0216] If the target neighborhood backlight area is the upper left neighborhood backlight area, the sub-area below it is adjacent to the sub-area above the first backlight area to be divided;

[0217] If the target neighborhood backlight area is the upper neighborhood sub-pixel, the sub-area below it is adjacent to the sub-area above the first backlight area to be divided;

[0218] If the target neighborhood backlight area is the neighborhood backlight area on the upper right side, the lowermost sub-area thereof is adjacent to the upper sub-area of ​​the first backlight area to be divided;

[0219] If the target neighborhood backlight area is the neighborhood backlight area on the left, the sub-area on the right side thereof is adjacent to the sub-area on the left side of the first backlight area to be divided;

[0220] If the target neighborhood backlight area is the neighborhood backlight area on the right, the sub-area on the left side thereof is adjacent to the sub-area on the right side of the first backlight area to be divided;

[0221] If the target neighborhood backlight area is the lower left neighborhood backlight area, the sub-area above it is adjacent to the sub-area below the first backlight area to be divided;

[0222] If the target neighborhood backlight area is the lower neighborhood backlight area, the sub-area above it is adjacent to the sub-area below the first backlight area to be divided;

[0223] If the target neighborhood backlight area is the lower right neighborhood backlight area, the sub-area above it is adjacent to the sub-area below the first backlight area to be divided.

[0224] If the color feature difference between the first backlight area BA1 and the target neighborhood backlight area BA is greater than the first threshold, the relationship between the grayscale features of the two adjacent sub-areas in the first backlight area to be divided and the target neighborhood backlight area BA and the grayscale threshold can be further judged. If the grayscale features of the two sub-areas are not greater than the grayscale threshold, the first backlight area to be divided is the first backlight area BA1.

[0225] Based on the above division of the first backlight area to be divided, the first backlight area to be divided that does not meet the first to third conditions is the second backlight area BA2, that is, when the following conditions are met, the first backlight area to be divided is divided into the second backlight area BA2:

[0226] The color feature difference between the first backlight area to be divided and the target neighborhood backlight area BA is greater than the first threshold and greater than the second threshold; or, the color feature difference between the first backlight area to be divided and the target neighborhood backlight area BA is greater than the first threshold, and the color feature difference between the sub-area adjacent to the first backlight area to be divided and the target neighborhood backlight area BA is greater than the first threshold; or, the color feature difference between the first backlight area to be divided and the target neighborhood backlight area BA is greater than the first threshold, and the grayscale feature of the sub-area adjacent to the first backlight area to be divided and the target neighborhood backlight area BA is not greater than the grayscale threshold.

[0227] In some embodiments of the present disclosure, one backlight area BA is selected as the second backlight area to be divided from the backlight area BA1 where the number of edge pixels corresponding to the first backlight area BA1 is less than the edge threshold and the number of color separation pixels corresponding to the first backlight area BA1 is not less than the separation threshold. Therefore, the second backlight area to be divided is divided into the first backlight area BA1 or the second backlight area BA2 based on the color feature difference and the grayscale feature difference. The following is a detailed description:

[0228] The second backlight area to be divided has fewer edge pixels than the first backlight area to be divided. Comparatively, it is less likely to cause color separation and thus has a greater probability of being divided into the second backlight area BA2.

[0229] If the color characteristic difference between the second backlight area to be divided and the target neighboring backlight area BA is not greater than the first threshold; and at least one of the neighboring backlight areas BA of the second backlight area to be divided is the first backlight area BA1, then it can be regarded as meeting the fourth condition, and the second backlight area to be divided can be divided into the first backlight area BA1; if the fourth condition is not met, the second backlight area to be divided is the second backlight area BA2.

[0230] In order to reduce the amount of calculation, it can be set to determine whether only part of the neighboring backlight areas BA are the first backlight area BA1. Taking the second backlight area to be divided as an example with 8 neighboring backlight areas BA, it is sufficient to determine whether only the neighboring backlight area BA on the left or upper left side is the first backlight area BA1.

[0231] In some embodiments of the present disclosure, one backlight area BA in which the number of color-separated pixels is less than the separation threshold can be selected as the third backlight area to be divided; the third backlight area to be divided is less likely to undergo color separation, but if there is a first backlight area BA1 in its neighboring backlight area BA that will undergo color separation, it is necessary to avoid a large color difference between the third backlight area to be divided and the neighboring backlight area BA. To this end, the third backlight area to be divided can be divided. If the third backlight area to be divided is adjacent to at least one first backlight area BA1, that is, there is a backlight area BA in the neighboring backlight area BA of the third backlight area to be divided that has been previously divided into the first backlight area BA1, then it can be regarded as meeting the fifth condition, and the third backlight area to be divided can be divided into the first backlight area BA1; if the fifth condition is not met, the third backlight area to be divided is the second backlight area BA2.

[0232] In order to reduce the amount of calculation, it can be set to determine whether only part of the neighboring backlight areas BA are the first backlight area BA1. Taking the third backlight area to be divided as an example with 8 neighboring backlight areas BA, it is only necessary to determine whether the neighboring backlight area BA on the left or upper left side is the first backlight area BA1.

[0233] Step S250 : establishing a first reference color gamut according to the color reflected by the initial color information of the pixels corresponding to the first backlight area BA1 , and determining n first reference primary colors according to the first reference color gamut.

[0234] For a frame of initial image, the initial grayscale of the pixels corresponding to the first backlight area BA1 can be used to establish a first reference color gamut of the first backlight area BA1 in the RGB color space. Each first backlight area BA1 can independently establish a first reference color gamut. Based on the first reference color gamut, n first reference primary colors can be determined, which serve as the primary colors of the first backlight area BA1 when displaying n field sequential images. For example, if n=3, the first reference color gamut can be a triangle, and the colors represented by the three vertices of the triangle are the three first reference primary colors. Since the first backlight area BA1 is only a backlight area BA, its first reference color gamut must be smaller than the color gamut determined based on the initial grayscale of all pixels of the liquid crystal display panel.

[0235] Step S260 : establishing a second reference color gamut according to the colors reflected by the initial color information of the pixels corresponding to each second backlight area BA2 , and determining n second reference primary colors according to the second reference color gamut.

[0236] For a frame of initial image, each second backlight area BA2 can be treated as a whole, and a second reference color gamut of the second backlight area BA2 can be established in the RGB color space based on the initial grayscale of the pixels corresponding to all the second backlight areas BA2. A second reference color gamut can be established for the second backlight area BA2. Based on a reference color gamut, n second reference primary colors can be determined as the primary colors of the second backlight area BA2 when displaying n field sequential images. For example, if n=3, the second reference color gamut can be a triangle, and the colors represented by the three vertices of the triangle are the three second reference primary colors. Since the second backlight area BA2 is only a partial backlight area BA, its second reference color gamut must be smaller than the color gamut determined based on the initial grayscale of all pixels of the liquid crystal display panel, but can be larger than the first reference color gamut.

[0237] In step S30, based on the initial color information of each pixel in an initial image frame and the above steps, the actual hue of each backlight area BA in each sub-field image can be determined. Specifically, in a sub-field image, the actual hue of a first backlight area BA1 is a first reference primary color. The actual hues of different first backlight areas BA1 may be different, that is, the first reference primary colors may be different, depending on the initial color information of the pixels corresponding to the different first backlight areas BA1. The actual hue of each second backlight area BA2 is a second reference primary color, and the actual hues of different second backlight areas BA2 are the same.

[0238] The first and second backlight areas BA1 and BA2 can be made to emit light according to the actual hue by controlling the color and number of light-emitting devices. For example, in a subfield image, the first backlight area BA1 can have at least two colors of light-emitting devices simultaneously emit light. By controlling the ratio of different colors among the illuminated light-emitting devices, the color of the first backlight area BA1 as a whole in a subfield image can be controlled to be the first reference primary color. That is, the color of the mixed colors of the light-emitting devices emitting in each backlight area BA in a subfield image is the color of the light emitted by that backlight area BA. The second backlight area BA2 displays according to the same principle as the first backlight area BA1, except that the first backlight area BA1 emits light based on independent actual hues, while each second backlight area BA2 emits light based on the same actual hue in a subfield image.

[0239] Each backlight area BA is controlled to emit light according to the actual color tone, and the pixels are controlled according to the initial gray scale to display n different sub-field images in sequence to obtain the mth frame actual image.

[0240] In addition, while the backlight area BA is emitting light, the control circuit can determine the actual grayscale of each pixel based on the initial color information, and control the deflection degree of the liquid crystal through the pixel electrode and the common electrode to form a subfield image in conjunction with the backlight. The n subfield images are mixed to form a frame of actual image.

[0241] In addition, in some embodiments of the present disclosure, the second backlight area BA2 may also emit backlight using a primary color determined based on the initial grayscales of all pixels of the liquid crystal display panel as the actual color tone.

[0242] As shown in FIG2 , in some embodiments of the present disclosure, the control circuit CU further includes a second operating mode, and in the second operating mode is configured to: upon receiving initial color information of the mth frame initial image, control the liquid crystal display device to sequentially display n subfield images based on the initial color information to obtain the mth frame image; m and n are positive integers, and n is greater than or equal to 2. The actual color information of each pixel is its initial color information, and the actual grayscale is its initial grayscale.

[0243] In the second operating mode, the light-emitting devices of the same color in each backlight area BA emit light, and the hue of each backlight area BA is the same. A primary color applicable to each backlight area BA can be determined based on the color gamut determined based on the initial color information of all pixels. In other words, in the second operating mode, the above-mentioned process of classifying the first backlight area BA1 and the second backlight area BA2 and re-determining the primary colors can be omitted.

[0244] The first and second operating modes described above can be activated upon receiving an activation signal. For example, an image capture device can capture an image of the user's eyeball, and an image processing device can determine the eyeball's movement speed based on the eyeball image. When the movement speed reaches a speed threshold, color separation becomes more pronounced. In this case, the control circuit CU can be placed in the first operating mode to eliminate color separation. When the movement speed does not reach the speed threshold, the color separation may be less pronounced. In this case, the control circuit CU can be placed in the second operating mode to improve operational efficiency.

[0245] It should be noted that although the steps of the image display method of the present disclosure are described in a specific order in the accompanying drawings, this does not require or imply that the steps must be performed in this specific order, or that all steps must be performed to achieve the desired results. Additionally or alternatively, certain steps may be omitted, multiple steps may be combined into one step, and / or a single step may be broken down into multiple steps.

[0246] An embodiment of the present disclosure provides an electronic device, which may include a liquid crystal display device. The structure of the liquid crystal display device may be the liquid crystal display device of any embodiment described above, which will not be described in detail here.

[0247] As shown in FIG7 , the electronic device further includes an image acquisition device CAM and an image processing device CP, wherein:

[0248] The image acquisition device CAM may include one or more cameras, and of course, other devices that can acquire image information such as human body or object feature information may also be used. The image acquisition device CAM can acquire images of the user's eyeballs in real time.

[0249] The image processing device CP can be connected to the image acquisition device CAM. It can determine the movement speed of the eyeball based on the image of the eyeball. When the movement speed reaches a speed threshold, it outputs a start signal to the control circuit CU, placing the control circuit CU in the first operating mode. If the movement speed does not reach the speed threshold, no start signal is output, and the control circuit CU is placed in the second operating mode.

[0250] The image processing device CP can identify the pupil center based on the image of the eyeball and determine the movement speed of the eyeball based on the change in the position of the pupil center.

[0251] In some embodiments, the electronic device may further include an infrared detection device that uses infrared light to locate the center of the user's cornea. The line connecting the corneal center and the pupil center identified by the image processing device is the optical axis of the visual system. The true line of sight can then be determined based on the angle between the optical axis and the visual axis. Furthermore, a thermal mirror may be included to reduce tracking errors without affecting the display; alternatively, an optical waveguide may be used to transmit infrared light and eye images.

[0252] In addition, eye tracking may also be achieved through other methods, which are not particularly limited here.

[0253] The electronic device disclosed herein may be a mobile phone, a television, a tablet computer, or a head-mounted display device such as smart glasses, which are not listed here one by one.

[0254] Those skilled in the art will readily appreciate other embodiments of the present disclosure after considering the specification and practicing the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of the present disclosure that follow the general principles of the present disclosure and include common knowledge or customary techniques in the art not disclosed herein. The description and examples are to be considered as exemplary only, with the true scope and spirit of the present disclosure being indicated by the appended claims.

Claims

1. A liquid crystal display device, comprising a liquid crystal display panel and a control circuit, wherein the liquid crystal display panel comprises a liquid crystal display substrate and a backlight module, wherein the liquid crystal display substrate comprises a plurality of pixels, and the backlight module comprises a plurality of backlight areas, wherein each of the backlight areas comprises light-emitting devices of n colors; The control circuit includes a first working mode, and in the first working mode is configured to: receive an m-th frame of initial image, control each of the liquid crystal display panels to sequentially display n different sub-field images, so as to obtain the m-th frame of actual image; m and n are positive integers, n≥2; the initial image includes initial color information of each of the pixels; the initial color information of the pixel includes initial grayscales under n tones; In one of the sub-field images, the backlight area includes a first backlight area and a plurality of second backlight areas; the first backlight area and the second backlight area emit light of different tones; and the second backlight areas emit light of the same tones.

2. The liquid crystal display device according to claim 1, wherein: In one of the sub-field images, the backlight area includes a plurality of first backlight areas; at least two of the first backlight areas emit light of different tones.

3. The liquid crystal display device according to claim 2, wherein: In a frame of actual image, the color reflected by the initial color information of the pixel corresponding to the first backlight area is located in a first reference color gamut determined based on n first reference primary colors; The color reflected by the initial color information of the pixels corresponding to each of the second backlight areas is in a second reference color gamut determined based on n second reference primary colors; In one of the sub-field images, the color tone of the first backlight area is the first reference primary color; and the color tone of the second backlight area is the second reference primary color.

4. The liquid crystal display device according to claim 3, wherein: Based on the initial color information of each pixel in a frame of initial image, the pixels include edge pixels and color separation pixels; the color separation pixels are pixels whose brightness is greater than a brightness threshold and whose saturation is less than a saturation threshold.

5. The liquid crystal display device according to claim 4, wherein: Taking one of the backlight areas as the center, a plurality of the backlight areas adjacent to the backlight area are neighboring backlight areas of the backlight area at the center; one of the neighboring backlight areas of the first backlight area is a target neighboring backlight area; In a frame of initial image, the colors of the first backlight area and the target neighborhood backlight area are The characteristic difference is not less than the color characteristic difference between the first backlight area and other neighboring backlight areas; the color characteristic difference of the backlight area is determined based on the color characteristic determined by the hue of each pixel corresponding to the backlight area.

6. The liquid crystal display device according to claim 5, wherein: In an initial image, the color features of any specified area satisfy the following relationship: H1+H2=C; C is the color feature of the designated area; H1 is the average value of the largest T% of the hues of the pixels corresponding to the designated area; H2 is the average value of the hues of the pixels corresponding to the designated area; The color characteristic difference between two adjacent backlight areas is the absolute value of the difference between the color characteristics of the two backlight areas.

7. The liquid crystal display device according to claim 6, wherein: n=3, the initial grayscale of the pixel in an initial image frame is (R, G, B), R is the grayscale of red, G is the grayscale of green, and B is the grayscale of blue; In a frame of the initial image, the hue of a pixel corresponding to a specified area satisfies the following relationship: h=floor(hs×30), hs≥0; or h=hs+180,hs<0; h is the hue of the pixel; hs is the reference hue of the pixel; The reference hue satisfies the following relationship: If the largest of the initial gray levels of a pixel is the red gray level R, then hs = (GB) / ((R-min(R, G, B)); If the largest of the initial grayscales of a pixel is the green grayscale G, then hs=2+(BR) / ((G-min(R, G, B)); If the largest of the initial grayscales of a pixel is the blue grayscale B, then hs=4+(RG) / (B-min(R, G, B)); min(R, G, B) is the minimum grayscale among the initial grayscales of the pixel.

8. The liquid crystal display device according to claim 7, wherein: Each of the backlight areas is divided into a plurality of sub-areas along a first direction and is divided into a plurality of sub-areas along a second direction; the first direction intersects with the second direction; In an initial image, the grayscale features of any specified area satisfy the following relationship: Gm+Ga=Gf; Gf is the grayscale feature of the designated area; Gm is the maximum grayscale of the grayscales of the pixels corresponding to the designated area; Ga is the average grayscale of the pixels corresponding to the designated area; In an initial image frame, the grayscale of a pixel and its initial grayscale satisfy the following relationship: G = k1 × R + k2 × G + k3 × B; k1, k2 and k3 are all positive numbers; In a frame of initial image, the number of edge pixels corresponding to the first backlight area is not less than an edge threshold, and the number of color separation pixels corresponding to the first backlight area is not less than a separation threshold; the first backlight area satisfies at least one of the following first condition, second condition and third condition: The first condition is that the difference in color characteristics between the first backlight area and the target neighborhood backlight area is not greater than a first threshold; The second condition is: the color feature difference between the first backlight area and the target neighborhood backlight area is greater than the first threshold and not greater than the second threshold; the color feature difference between the first backlight area and the adjacent sub-area in the target neighborhood backlight area is not greater than the first threshold; The third condition is: the difference in color characteristics between the first backlight area and the target neighborhood backlight area is greater than the first threshold, and the grayscale characteristic of at least one of the adjacent sub-areas between the first backlight area and the target neighborhood backlight area is not greater than the grayscale threshold; The second backlight area does not satisfy the first condition, the second condition, and the third condition.

9. The liquid crystal display device according to claim 8, wherein: In an initial image frame, the number of edge pixels corresponding to the first backlight area is less than the edge threshold, and the number of color separation pixels corresponding to the first backlight area is not less than the separation threshold; the first backlight area satisfies the fourth condition: The fourth condition is that: the color feature difference between the first backlight area and the target neighborhood backlight area is not greater than a first threshold; and the first backlight area is adjacent to at least one of the first backlight areas; The second backlight area does not satisfy the fourth condition.

10. The liquid crystal display device according to claim 8, wherein: The number of color separation pixels corresponding to the first backlight area is less than the separation threshold; and the first backlight area satisfies the fifth condition: The fifth condition is: the first backlight area is adjacent to at least one of the first backlight areas; The second backlight area does not satisfy the fifth condition.

11. The liquid crystal display device according to any one of claims 1 to 10, wherein: The control circuit further includes a second working mode, and in the second working mode is configured to: receive the mth frame initial image, and control the liquid crystal display device to display n sub-field images in sequence according to the initial color information of each pixel to obtain the mth frame image; In a subfield image of the second working mode, light emitting devices of the same color in each backlight area emit light.

12. The liquid crystal display device according to any one of claims 1 to 10, wherein: The liquid crystal display substrate comprises: An array substrate and a counter substrate arranged opposite to each other; A liquid crystal layer, disposed between the array substrate and the counter substrate; The control circuit is connected to the array substrate and the backlight module.

13. An image display method, used in a liquid crystal display device, the liquid crystal display device comprising a liquid crystal display panel and a control circuit, the liquid crystal display panel comprising a liquid crystal display substrate and a backlight module, the liquid crystal display substrate comprising a plurality of pixels, the backlight module comprising a plurality of backlight areas, each of the backlight areas comprising light emitting devices of n colors; The image display method comprises: In the first working mode: Receive an m-th frame of initial image, wherein the initial image includes initial color information of each pixel; the initial color information of each pixel includes initial grayscales under n tones; m and n are positive integers, and n≥2; Determine the actual color tone of each of the backlight areas under n sub-field images according to the initial color information; Controlling each of the backlight areas to emit light according to the actual color tone, and controlling the pixels according to the initial grayscale, and sequentially displaying n different subfield images to obtain the mth frame actual image; In one of the sub-field images, the backlight area includes a first backlight area and a plurality of second backlight areas; the actual hues of light emitted by the first backlight area and the second backlight area are different; and the actual hues of light emitted by each of the second backlight areas are the same.

14. The image display method according to claim 13, wherein: Determine the actual color tone of each of the backlight areas under n sub-field images according to the initial color information; include: Determine edge pixels in the initial image according to the initial color information; Determine the hue, saturation and brightness of each pixel according to the initial color information; Determine the color separation pixel and the color characteristics and grayscale characteristics of each of the backlight areas according to the hue, saturation and brightness of each of the pixels; the color separation pixel is a pixel whose brightness is greater than a brightness threshold and whose saturation is less than a saturation threshold; Dividing each of the backlight areas into at least a first backlight area and a second backlight area according to the color characteristics and the grayscale characteristics of the backlight area; Establishing a first reference color gamut according to the color reflected by the initial color information of the pixel corresponding to the first backlight area, and determining n first reference primary colors according to the first reference color gamut; Establishing a second reference color gamut according to the color reflected by the initial color information of the pixels corresponding to each of the second backlight areas, and determining n second reference primary colors according to the second reference color gamut; Controlling each of the backlight areas to emit light according to the actual color tone; comprising: In one of the sub-field images, the actual color tone of the light emitted from the first backlight area is controlled to be the first reference primary color; and the actual color tone of the light emitted from the second backlight area is controlled to be the second reference primary color.

15. The image display method according to claim 13, wherein: Determining edge pixels in the initial image according to the initial color information; comprising: Gray-scaling the initial image to obtain the gray scale of each pixel; Determine the gradient magnitude and gradient direction of each pixel according to the grayscale of each pixel; An edge pixel among the pixels is determined according to the gradient magnitude and the gradient direction of the pixels.

16. The image display method according to claim 14, wherein: n=3, the initial grayscale of the pixel in an initial image frame is (R, G, B), R is the grayscale of red, G is the grayscale of green, and B is the grayscale of blue; In a frame of initial image, the hue of a pixel satisfies the following relationship: h=floor(hs×30), hs≥0; or h=hs+180,hs<0; h is the hue of the pixel; hs is the reference hue of the pixel; The reference hue satisfies the following relationship: If the largest of the initial gray levels of a pixel is the red gray level R, then hs = (GB) / ((R-min(R, G, B)); If the largest of the initial grayscales of a pixel is the green grayscale G, then hs=2+(BR) / ((G-min(R, G, B)); If the largest of the initial grayscales of a pixel is the blue grayscale B, then hs=4+(RG) / (B-min(R, G, B)); min(R, G, B) is the minimum grayscale among the initial grayscales of the pixel; The saturation of the pixel satisfies the following relationship: S = 1-W / max(R, G, B); S is the saturation of the pixel; W is the second largest grayscale among the initial grayscales of the pixel; max(R, G, B) is the largest grayscale among the initial grayscales of the pixel; The brightness of a pixel is the maximum gray level among its initial gray levels.

17. The image display method according to claim 16, wherein: The color separation pixel is a pixel whose brightness is less than a brightness threshold and whose saturation is greater than a saturation threshold; In an initial image, the color features of any specified area satisfy the following relationship: H1+H2=C; C is the color feature of the designated area; H1 is the average value of the largest T% of the hues of the pixels corresponding to the designated area; H2 is the average value of the hues of the pixels corresponding to the designated area; The color characteristic difference between two adjacent backlight areas is the absolute value of the difference between the color characteristics of the two backlight areas; In an initial image, the grayscale features of any specified area satisfy the following relationship: Gm+Ga=Gf; Gf is the grayscale feature of the designated area; Gm is the maximum grayscale of the grayscales of the pixels corresponding to the designated area; Ga is the average grayscale of the pixels corresponding to the designated area; In an initial image frame, the grayscale of a pixel and its initial grayscale satisfy the following relationship: G = k1 × R + k2 × G + k3 × B; k1, k2 and k3 are all positive numbers.

18. The image display method according to claim 17, wherein: Dividing each of the backlight areas into at least a first backlight area and a second backlight area according to the color characteristics and grayscale characteristics of the backlight area; comprising: Dividing each of the backlight areas into a plurality of sub-areas along a first direction and into a plurality of sub-areas along a second direction; the first direction intersects the second direction; Selecting one of the backlight areas in which the number of edge pixels is not less than the edge threshold and the number of color separation pixels is not less than the separation threshold as a first backlight area to be divided; Taking the first backlight area to be divided as the center, respectively determining the color feature difference and grayscale feature difference between the first backlight area to be divided and its adjacent neighborhood backlight area; and taking the neighborhood backlight area with the largest color feature difference as the target neighborhood backlight area; Determine the difference in color characteristics between the first backlight area to be divided and the adjacent sub-areas in the target neighborhood backlight area; If the color feature difference between the first backlight area to be divided and the target neighborhood backlight area is not greater than a first threshold, the first condition is met, and the first backlight area to be divided is the first backlight area; If the color feature difference between the first backlight area and the target neighborhood backlight area is greater than the first threshold and not greater than the second threshold; the color feature difference between the first backlight area to be divided and the adjacent sub-areas in the target neighborhood backlight area is not greater than the first threshold; then the second condition is met and the first backlight area to be divided is the first backlight area; If the difference in color characteristics between the first backlight area and the target neighborhood backlight area is greater than the first threshold, and the grayscale characteristic of at least one of the adjacent sub-areas between the first backlight area and the target neighborhood backlight area is not greater than the grayscale threshold, then the third condition is met and the first backlight area to be divided is the first backlight area; If the first condition, the second condition and the third condition are not satisfied, the first backlight area to be divided is the second backlight area.

19. The image display method according to claim 18, wherein: According to the color characteristics and grayscale characteristics of the backlight area, each of the backlight areas is at least divided into a first backlight area and a second backlight area; and further comprising: Select one from the backlight areas where the number of edge pixels corresponding to the first backlight area is less than the edge threshold and the number of color separation pixels corresponding to the first backlight area is not less than the separation threshold as the second backlight area to be divided; If the color characteristic difference between the second backlight area to be divided and the target neighborhood backlight area is not greater than a first threshold, and at least one of the neighborhood backlight areas of the second backlight area to be divided is If the first backlight area is satisfied, the fourth condition is satisfied and the second backlight area to be divided is the first backlight area; if the fourth condition is not satisfied, the second backlight area to be divided is the second backlight area.

20. The image display method according to claim 18, wherein: According to the color characteristics and grayscale characteristics of the backlight area, each of the backlight areas is at least divided into a first backlight area and a second backlight area; and further comprising: Selecting one from the backlight areas where the number of color separation pixels is less than the separation threshold as a third backlight area to be divided; If the third backlight area to be divided is adjacent to at least one of the first backlight areas, the fifth condition is met and the third backlight area to be divided is the first backlight area; if the fifth condition is not met, the third backlight area to be divided is the second backlight area.

21. An electronic device comprising the liquid crystal display device according to any one of claims 1 to 12.

Images