Partitioned color mixing method based on spatial color mixing and time color mixing conversion principle

Abstract

The application provides a partition color adjusting method based on space color mixing and time color mixing conversion principle. The space color mixing and time color mixing light intensity conversion function relationship is obtained by making the light emitting effect of space color mixing and the light emitting effect based on time color mixing equivalent. The multi-primary color is displayed in turn based on the time color mixing principle to perform backlight partition color adjusting control. Thus, the liquid crystal display technology with high display quality considering super high resolution and super high gray scale is realized.

Description

Technical Field

[0001] The present invention belongs to the technical field of backlight partition color adjustment display technology, and in particular relates to a partition color adjustment method based on the principle of spatial color mixing and temporal color mixing conversion. Background Art

[0002] Liquid crystal display technology is one of the current mainstream display technologies, and it is widely used in electronic products, including televisions, mobile phones, and tablets. In LCD display technology, the design and performance of the backlight module have a crucial impact on the display effect. Traditional LCD displays use the principle of spatial color mixing, and the backlight technology usually uses global dimming, that is, the brightness and color of the entire screen are adjusted uniformly. However, this technology has certain limitations in displaying color details and contrast, especially when more realistic and rich colors are needed. Therefore, with the development of LED miniaturization and full-color technology, LCD zone dimming technology has also developed rapidly, but it can still only achieve local brightness adjustment but not local color adjustment. Summary of the Invention

[0003] In response to the defects and shortcomings of the existing technology, the present invention proposes a new liquid crystal display partition color adjustment technology, which converts the traditional liquid crystal display technology based on the RGB three-primary color space color mixing principle into a liquid crystal display technology based on the rapid display of RGB three-primary color subframes in turn; the display screen is divided into multiple display areas, and then the single primary color light output brightness of the corresponding backlight area is modulated separately in each primary color subframe according to the display requirements.

[0004] This solution combines the human eye visual display principle and mathematical derivation. By making the lighting effect of spatial color mixing equivalent to the lighting effect based on time color mixing, it derives the light intensity conversion function relationship between spatial color mixing and time color mixing; and further obtains a backlight partition color adjustment display technology based on the time color mixing principle, realizing a high display quality LCD display technology that takes into account ultra-high resolution and ultra-high grayscale.

[0005] Compared to traditional spatial color mixing, LCD zone color mixing technology switches between spatial and temporal color mixing within each LCD pixel. This technology not only enables zone-by-zone modulation of brightness but also color. More importantly, it transforms the traditional three-pixel structure of LCD displays into a single-pixel structure. This technology facilitates the realization of LCD displays with ultra-high resolution and ultra-high grayscale, providing users with more realistic, vivid, and detailed color rendering and superior visual experience.

[0006] The technical solution specifically adopted by the present invention to solve the technical problem is:

[0007] A partition color adjustment method based on the principle of spatial color mixing and temporal color mixing conversion is proposed. The spatial color mixing and temporal color mixing light intensity conversion function relationship is obtained by making the light emission effect of spatial color mixing equivalent to the light emission effect based on temporal color mixing. Based on the temporal color mixing principle, multiple primary colors are displayed in turn to perform backlight partition color adjustment control.

[0008] Furthermore, according to the principle of temporal color mixing, a frame of image is divided into a corresponding number of single-primary-color subframes according to the number of primary colors. When the primary-color subframes are displayed in turn in a certain order and the refresh frequency meets the requirements, and the luminous brightness of the single primary color in the corresponding display area is equal, it is equivalent to direct mixing of the primary color lights.

[0009] Furthermore, within a single primary color subframe, the luminance of a single pixel has the following relationship:

[0010]

[0011] Among them, s represents a certain primary color, Y S Indicates the final brightness of the single primary color s when mixing colors in space, Y s ' is the final brightness of the single primary color s in time mixing, a is the proportional coefficient, which is a positive constant; n is the total number of subframes corresponding to the time mixing method when the single primary color is used; k is the subframe number, 1≤k≤n; Y k is the backlight brightness of the kth subframe; σ k is the liquid crystal transmittance in the kth subframe; t k is the backlight on time in the kth subframe; T s is the total time of the s-primary color subframe; q is the ratio of the backlight on time to the total time in a single primary color subframe, that is, the backlight duty cycle corresponding to the s-primary color subframe;

[0012] When the t of each single primary color subframe k When consistent, the following expressions are related to time mixing:

[0013]

[0014] Formula (2) is used to realize the brightness of a single primary color of a pixel based on the principle of time mixing.

[0015] Furthermore, for a three-primary-color liquid crystal display, the three primary-color luminance expressions are:

[0016]

[0017] Among them, Y rk 、Y gk 、Y bk are the luminance components of the kth subframe corresponding to the red, green, and blue subframes respectively.

[0018] Furthermore, the color adjustment method adopted is: adjustment based on the time duty cycle q; within a single primary color subframe, by adjusting the ratio q of the backlight on time of each backlight partition to the total time, the light intensity of each backlight partition within the single primary color subframe is adjusted; by superimposing the modulation effects of other primary color subframes, the light intensity and light color of each liquid crystal backlight partition are modulated separately.

[0019] Furthermore, the color adjustment method adopted is: adjusting according to the light sources with adjustable brightness of the three primary colors of RGB; and modulating the brightness using the adjustable light sources in the backlight partitions in different primary color subframes.

[0020] If further combined with the liquid crystal modulation method for spatial light of display pixels (reference 1. twistednematic liquid-crystal displays," Journal of Applied Physics, vol. 62, no. 5, pp. 1717-1733, 1987.

[0021] 2.ARBahadur, "Liquid Crystal Display Devices: Principles, Design, and Implementation," SPIE Press, 30Nov.1999.

[0022] 3.Y.Hsu,et al.,"High-performance twisted nematic liquid-crystal display employing a novel compensation film,"Optics Express,vol.28,no.6,pp.7453-7467,2020.,etc.) can make the entire liquid crystal display have ultra-high grayscale modulation capability.

[0023] Furthermore, according to formula (2), the method for adjusting the light output brightness of a single pixel in a single primary color subframe is as follows: the light output brightness of the pixel in the single primary color subframe is achieved by modulating the transmittance of the pixel molecule and the light output brightness of the corresponding backlight partition, or by adjusting the backlight on duty cycle q and the number of subframes n of the primary color.

[0024] Furthermore, different values ​​of the total number of subframes n of a single primary color can achieve different display modes. The method is as follows:

[0025] 1) When n is 1, that is, no sub-frame is divided, and a single frame is used to realize three-primary color display, that is, the traditional spatial color mixing technology. At this time, the brightness of a single primary color of a single liquid crystal pixel is:

[0026] Y′ S =q·Y k ·σ k (4)

[0027] 2) When n is 2, it is a two-frame display technology based on time-mixing. This technology provides a theoretical basis for frame reduction for the current mainstream three-subframe field sequential display technology, thereby reducing the high refresh rate requirements of field sequential LCDs. At this time, the brightness of a single LCD pixel is:

[0028]

[0029] 3) When n is 3, which is the current mainstream RGB three-subframe field sequential LCD display method, the brightness of a single LCD pixel is:

[0030]

[0031] 4) When n is greater than 3, that is, the multi-subframe color mixing method, the brightness of a single liquid crystal pixel is:

[0032]

[0033] This formula provides a theoretical basis for multi-primary color sub-frame display technology.

[0034] Furthermore, according to different display requirements, there can be different selection and combination methods for color s. The details are as follows:

[0035] 1) When a color is selected, it is displayed in monochrome mode

[0036] 2) When two different colors are selected, in order to meet the white balance requirements of color display, the two colors should be complementary colors. This method is suitable for the complementary color mixing display method based on the time mixing principle.

[0037] 3) When three different colors are selected, in order to meet the white balance requirements of color display, the color combination must be a combination of three colors based on the three primary colors.

[0038] 4) When more than three different colors are selected, a very large color gamut can be displayed. Taking the six-primary color display scheme as an example, s can be magenta, red, yellow, green, cyan, and blue.

[0039] Furthermore, the turn-on time t of the single primary color subframe backlight k The different value implementation methods of are as follows:

[0040] 1)t k Same, indicating that each single-primary-color subframe has the same time;

[0041] 2)t kDifferent, press t k =2t k-1 The subframe time is divided in this way, and 1≤k≤n is satisfied; the ratio of the lighting time of each subframe is: 1:2:4:…:256:…:2 n , n is in the range of [1, 100];

[0042] 3)t k Different, according to the different spectral visibility of the three primary colors of red, green and blue by the human eye k Perform adaptation and determine the corresponding t of the three primary colors of red, green and blue k This solution can make the display screen more suitable for the human eye and improve the visual effect.

[0043] Furthermore, for the mapping relationship between the image data and the light source data of the backlight in the partition color adjustment, consider that formula (2) is established for each pixel. Assuming that the number of pixels corresponding to a single backlight partition is i×j, when corresponding to the kth subframe, the light output brightness of each pixel corresponding to the single backlight partition satisfies the following relationship:

[0044] For a single primary color s, the following equation holds true:

[0045]

[0046] Among them [Y s '] represents the time-mixed backlight brightness matrix of the entire partition, which represents the brightness of each pixel in the partition, and Y S '(i,j) represents the time-mixed backlight brightness of the pixel with coordinates (i,j) relative to partition a; Y k (i, j) represents the backlight brightness of the spatial mixed color of the pixel with coordinates (i, j) relative to partition a; σ k (i, j) represents the liquid crystal transmittance of the pixel with coordinates (i, j) relative to partition a. Since the backlight intensity in a single partition is the same, and a single partition has a total of i×j pixels, the brightness of a single backlight partition after the liquid crystal is obtained by weighted calculation of the displayed image data:

[0047] Y'=f(Y S ') (9)

[0048] Y' represents the brightness data of a single backlight partition RGBLED driver; Y S ' is the backlight brightness matrix of a single partition, representing the backlight brightness value of each pixel in the entire partition; f(Y S ') represents a function f applied to the brightness of each pixel.

[0049] The above weighted calculation method may include but is not limited to the following methods: weighted average, weighted maximum, and weighted minimum.

[0050] At this point, the LED driving light intensity of a single partition in the partition color adjustment can be obtained, thereby realizing the conversion of image data into backlight data.

[0051] Furthermore, gamma correction is used in the conversion process of the display image data stream to LED light intensity data; the LED light intensity data after gamma correction is:

[0052] Y γ '=f[(Y S ') γ ] (10)

[0053] where Y γ ' is the LED light intensity data after gamma correction; the γ value is usually a positive real number, ranging from 0.1 to 100, depending on the screen's optoelectronic display characteristics. It can improve the visual effect of the image and improve brightness and contrast.

[0054] Furthermore, the proportional coefficient a is used to adjust the requirement of linear enhancement or linear reduction of the brightness value;

[0055] When the value range of a is [0,1), it means that the brightness of the mutual transformation between temporal color mixing and spatial color mixing needs to be reduced linearly;

[0056] When the value interval of a is equal to 1, it means that the brightness of the conversion between temporal color mixing and spatial color mixing is equal;

[0057] When the value range of a is greater than 1, it means that the brightness of the conversion between temporal color mixing and spatial color mixing needs to increase linearly.

[0058] Compared to existing technologies, this invention and its preferred embodiment provide a feasible conversion scheme for the visual equivalence of temporal and spatial color mixing in liquid crystal displays (LCDs), and lay the foundation for the implementation of sequential LCD color grading technology. Based on the visual characteristics of the human eye and mathematical theory, this technology derives the mapping relationship between the display data of temporal and spatial color mixing in LCDs. Furthermore, it develops a LCD color grading display technology based on the principle of temporal color mixing, achieving high-quality LCD displays that combine ultra-high resolution with ultra-high grayscale. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments:

[0060] Figure 1 Schematic diagram of conversion between spatial color mixing and temporal color mixing in an embodiment of the present invention;

[0061] Figure 2 1 is a principle block diagram of a partition color adjustment method based on the spatial color mixing and temporal color mixing conversion principles in an embodiment of the present invention;

[0062] Figure 3 Schematic diagram of the relationship between liquid crystal backlight partitions and corresponding pixels within the partitions in an embodiment of the present invention;

[0063] Figure 4 Schematic diagram of gamma correction of liquid crystal pixel brightness and conversion of backlight partition luminous brightness in an embodiment of the present invention. DETAILED DESCRIPTION

[0064] To make the features and advantages of this patent more clearly understood, the following embodiments are specifically described in detail as follows:

[0065] It should be noted that the following detailed description is illustrative and is intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used in this specification have the same meaning as commonly understood by those skilled in the art to which this application belongs.

[0066] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof.

[0067] The solution provided by the embodiments of the present invention converts traditional liquid crystal display technology based on spatial color mixing of the RGB three primary colors into a multi-subframe liquid crystal display technology based on temporal color mixing. According to the temporal color mixing principle, a frame of an image is divided into three corresponding single-primary color subframes according to the RGB color. When the three primary color subframes are displayed in a certain order and the refresh rate is fast enough, the color perception produced by the human eye is the same as when the three primary colors are directly mixed. Therefore, the display effects based on temporal color mixing and spatial color mixing must be the same, and furthermore, the luminous brightness of the single primary color in the corresponding display area must be equal.

[0068] Considering that within a single primary color subframe, the brightness and chromaticity of the light emitted by the liquid crystal molecules must be consistent with the brightness and chromaticity of the light emitted by the primary color liquid crystal molecules based on the principle of spatial color mixing; since brightness is proportional to light intensity, and chromaticity also depends on the mixing of different primary color light intensities, the brightness of a single liquid crystal pixel within a single primary color subframe exists in the following expression group:

[0069]

[0070] Among them, s represents a certain primary color, Y S Indicates the final brightness of the single primary color s when mixing colors in space, Y s' is the final brightness of the single primary color s in time mixing; n is the total number of subframes corresponding to the time mixing method for a single primary color; k is the subframe number, 1≤k≤n; Y k is the backlight brightness of the kth subframe; σ k is the liquid crystal transmittance in the kth subframe; t k is the backlight on time in the kth subframe; T s is the total time of the s-primary color subframe; q is the ratio of the backlight-on time to the total time in a single primary color subframe, that is, the backlight duty cycle corresponding to the s-primary color subframe.

[0071] When the t of each single primary color subframe k When consistent, the following expressions are related to time mixing:

[0072]

[0073] This expression shows the method for achieving the final brightness of the light emitted by a single primary color s corresponding to a single pixel of the liquid crystal.

[0074] Therefore, the corresponding expression of the three primary colors luminous intensity based on the time mixing principle is:

[0075]

[0076] The derivation process of the above design is as follows:

[0077] When the three primary color subframes are displayed in a certain order and the refresh frequency is fast enough, the color perception produced by the human eye is the same as when the three primary colors are directly mixed. Therefore, the display effects based on temporal color mixing and spatial color mixing must be the same, and further, the luminous brightness of the single primary color in the corresponding display area must be equal. Therefore,

[0078] Y S =aY′ S

[0079] Assuming that the light intensity of a single partition in a single subframe is the same, the liquid crystal transmittance of the partition color display is σ k , the monochrome backlight intensity is Y k , when the number of sub-frames divided to achieve full-color display is n (positive integer), the backlight on time for the kth sub-frame is t k . Define Y S The final brightness of the corresponding single primary color s when spatial color mixing is equivalent brightness, which is a time function of the light source intensity, so:

[0080] L k (t) = Y k ·σ k

[0081] Only the monochrome S, S = (R, G, B) is discussed: the monochrome S backlight intensity of each subframe is:

[0082] S1, S2, S3, ..., S k

[0083] Assuming the duration of one frame is T, the perceived brightness of the disk is linearly related to the duty cycle of the white exposure during the periodic interval. This relationship between exposure time and brightness is known as Talbot's law. According to Talbot's law, the final mixed color light intensity is:

[0084]

[0085] Among them I s It is the intensity of monochromatic light of traditional display.

[0086] Assume that the backlight is on for a certain time in each subframe k are equal, the backlight is turned off during the subframe c The number of subframes is n (n is a positive integer), and we get:

[0087]

[0088] Substitute into the above formula to get:

[0089]

[0090] After sorting, we get

[0091]

[0092] Among them are The ratio of the backlight on time to the total time in a frame, that is, the backlight duty cycle q, is substituted into the equation to obtain the following formula:

[0093]

[0094] The traditional liquid crystal display technology based on the principle of spatial color mixing of RGB three primary colors is converted into a liquid crystal display technology based on the principle of time color mixing with multiple subframes. According to the principle of time color mixing, a frame of image is divided into three corresponding single primary color subframes according to RGB color. When the three primary color subframes are displayed in a certain order and the refresh frequency is fast enough, the color perception produced by the human eye is the same as when the three primary colors are directly mixed. Therefore, the display effects based on time color mixing and space color mixing are required to be the same, and further, the luminous brightness of the single primary color in the corresponding display area must be equal. Within the time of a single primary color subframe, the brightness and chromaticity of the light emitted by the liquid crystal molecules must be consistent with the brightness and chromaticity of the light emitted by the primary color liquid crystal molecules based on the principle of spatial color mixing. Since the brightness is proportional to the light intensity, and the chromaticity also depends on the mixing of different primary color light intensities, as a further technical solution of the present invention, within a single primary color subframe, the light output brightness of a single liquid crystal pixel exists in the following expression group:

[0095]

[0096] Among them, s represents a certain primary color, Y s Indicates the final brightness of the single primary color s when mixing colors in space, Y s ' is the final brightness of the single primary color s in time mixing; n is the total number of subframes corresponding to the time mixing method for a single primary color; k is the subframe number, 1≤k≤n; Y k is the backlight brightness of the kth subframe; σ k is the liquid crystal transmittance in the kth subframe; t k is the backlight on time in the kth subframe; T s is the total time of the s-primary color subframe; q is the ratio of the backlight-on time to the total time in a single primary color subframe, that is, the backlight duty cycle corresponding to the s-primary color subframe.

[0097] As a further technical solution of the present invention, when t of each single primary color subframe k When consistent, the following expressions are related to time mixing:

[0098]

[0099] This formula shows the method for achieving the final brightness of the light emitted by a single primary color s corresponding to a single pixel of the liquid crystal.

[0100] The corresponding expression of the luminous intensity of the three primary colors based on the time mixing principle is:

[0101]

[0102] Based on the above design, we can further:

[0103] The brightness value of the liquid crystal pixel can be achieved by modulating the transmittance of the liquid crystal molecules and the brightness of the corresponding backlight partition, and the transmittance of the liquid crystal molecules and the backlight partition brightness value are both related to the displayed image data, and can be achieved through the corresponding existing image data to backlight partition brightness data related algorithm.

[0104] According to the above expression group, it can be found that the brightness value of the liquid crystal molecules can also be achieved from a temporal perspective by adjusting the backlight on duty cycle q and the total number of subframes n of the primary color:

[0105] As a further technical solution of the present invention, the backlight duty cycle q is adjusted as follows:

[0106] 1) In order to achieve high brightness and high image quality color presentation on the display, the value of q should be large.

[0107] 2) In order for the display to work in certain extreme conditions, such as high-brightness environments, it needs to present extremely high brightness. In this case, q can be 1.

[0108] 3) In order to extend the service life of the display and make it energy-efficient, the value of q should be small, but it must meet the basic requirements of the display and cannot be too low to cause excessive brightness and damage the human eye.

[0109] As a further technical solution of the present invention, the total number of subframes n is adjusted as follows:

[0110] 1) In order to realize the traditional spatial color mixing technology, take n as 1 and use a single frame to realize the three-primary color display. At this time, the brightness of a single primary color of a single liquid crystal pixel is Y S '=q·Y k ·σ k

[0111] 2) In order to achieve a two-subframe display method with high refresh rate and high color mixing efficiency, n is set to 2. This technology provides a theoretical basis for frame reduction for the current mainstream three-subframe field sequential display technology, thereby reducing the requirements of traditional field sequential displays for high refresh rate. At this time, the light output brightness of a single LCD pixel is

[0112] 3) In order to realize the mainstream RGB three-subframe field sequential liquid crystal display method of the current sequential color mixing display, n is taken as 3. At this time, the light output brightness of a single liquid crystal pixel is

[0113] 4) In order to realize the multi-subframe color mixing method and provide a theoretical basis for the multi-primary color subframe display technology, n is set to be greater than 3. At this time, the light output brightness of a single liquid crystal pixel is

[0114] When different display control methods are required, different n values ​​can be selected to achieve display brightness control. For example, when the three-subframe color mixing and partitioning color grading technology has high refresh rate requirements, a frame reduction algorithm with n = 2 can be selected to minimize the high refresh rate requirements while still achieving color display.

[0115] As a further technical solution of the present invention, the liquid crystal backlight partition color adjustment technology can not only realize brightness adjustment within the backlight partition, but also adjust the color information in the backlight partition according to the time duty cycle. In a single primary color subframe, the modulation method of the duty cycle q in formula (2) is applied to the corresponding liquid crystal backlight partitions, which can realize the adjustment of the light intensity of each backlight partition within the single primary color subframe; and then superimpose the modulation effect of other different primary color subframes, thereby realizing the separate modulation of the light intensity and light color of each liquid crystal backlight partition.

[0116] When the backlight partition light source uses a light source with adjustable luminous intensity for the three primary colors of RGB, the backlight partition will have the function of modulating the luminous brightness. Combined with the grayscale modulation function of the LCD pixels, the entire LCD display has the ability to express ultra-high grayscale. This makes this LCD display backlight partition color adjustment technology suitable for LCD displays with ultra-high resolution and ultra-high grayscale.

[0117] As a further technical solution of the present invention, there are different methods for selecting and combining the colors s, including but not limited to the following methods:

[0118] 1) In order to simplify the display, save energy and extend the life of the display, only one color is selected to implement monochrome display.

[0119] 2) In order to reduce the high requirements of the three-subframe time mixing display on the display resolution, two complementary colors are selected to meet the white balance requirements of the color display. This method is suitable for the complementary color mixing display method based on the time mixing principle.

[0120] 3) In order to achieve the current mainstream three-primary color display and adapt to the current display production line and production method, three different colors that meet the white balance requirements of color display are selected, and the color combination must be a combination of three colors based on the three primary colors.

[0121] 4) In order to expand the color gamut of the display or widen the adjustable range of the display and improve the display effect of the display, select more than 3 different colors.

[0122] As a further technical solution of the present invention, t k The options include but are not limited to the following division methods:

[0123] 1) In order to adapt to the current mainstream display driver circuit, take tk The same indicates that the time of each single primary color subframe is the same.

[0124] 2) In order to achieve high refresh rate, reduce motion blur and reduce eye fatigue, take t k Different, press t k =2t k-1 The subframe time is divided in this way, and 1≤k≤n is satisfied. Taking n=8 as an example, the ratio of the lighting time of each subframe is: 1:2:4:…:256:…:2 n This method can be extended to PDP sub-field display technology.

[0125] 3) In order to increase the visual effect of human eyes and improve the color quality, take t k Different, according to the different spectral viewing rates of the three primary colors of red, green and blue, k Perform adaptation and determine the corresponding t of the three primary colors of red, green and blue k This method can make the display screen more suitable for the human eye and improve the visual effect.

[0126] In the mapping relationship for the mutual conversion of backlight light source data, since the first expression 2 is established for each pixel, assuming that the number of pixels corresponding to a single backlight partition is i×j, then for the kth subframe, the light output brightness of each pixel corresponding to the single backlight partition satisfies the following relationship. Therefore, when a single primary color S is displayed, the following equation is established:

[0127]

[0128] where Y S (i, j) and Y(i, j) represent the relative coordinates of the pixel with respect to partition a. Since the backlight intensity in a single partition is the same, and a single partition has i*j pixels, the brightness of a single backlight partition after leaving the liquid crystal is obtained by weighted calculation of the displayed image data. Taking the weighted average algorithm as an example, we can get:

[0129]

[0130] Y' represents the brightness data of a single backlight partition RGBLED driver; Y S' is the backlight brightness matrix of a single partition, representing the brightness value of the backlight of each pixel in the entire partition. Weighted calculation is to ensure that the brightness of each pixel has a balanced impact on the overall image. In the process of weighted calculation of display image data, the brightness values ​​of different pixels may be different. Through weighted calculation, the effects of pixels with higher brightness values ​​and pixels with lower brightness values ​​on the overall image can be balanced, so that the brightness of a single backlight partition after the liquid crystal is obtained is more uniform and stable. This can improve the display effect and make the image clearer and more realistic. The present invention obtains the LED driving light intensity of a single partition in the partition color adjustment through weighted calculation, thereby realizing the conversion of image data to backlight data.

[0131] In order to better restore the image, the present invention further adds a gamma correction link based on the photoelectric display characteristics of the screen. γ 'The data is:

[0132]

[0133] Gamma correction is a method used to adjust image brightness and contrast, altering the image's appearance by performing a nonlinear transformation on pixel values. Combining weighted calculations with gamma correction allows for nonlinear adjustments to the data, based on the average value, to better reflect the characteristics and impact of different data. This results in calculations that are more realistic and suitable for specific application scenarios.

[0134] It's important to note that the gamma value is typically a positive real number, ranging from 0.1 to 10, depending on the screen's electro-optical display characteristics. Adjusting the gamma value (gamma) alters the image's brightness and contrast to improve visual quality. Generally, increasing the gamma value makes dark details more prominent while reducing bright details. This adjustment enhances image contrast, making the image clearer and sharper. Decreasing the gamma value makes bright details more prominent while reducing dark details. This adjustment reduces image contrast, making the image softer and smoother. Therefore, for images that require more detail and contrast, increase the gamma value; for images that require less contrast and a softer image, decrease the gamma value. When adjusting the gamma value, experiment with different values ​​to observe how the image changes and find the most suitable gamma value.

[0135] The proportional coefficient a reflects the corresponding brightness proportional relationship when the liquid crystal pixel emits light when the temporal color mixing and the spatial color mixing are transformed into each other. Different values ​​of a can meet the needs of linear enhancement or linear reduction of the brightness value.

[0136] When the value range of a is [0,1), it means that the brightness of the mutual transformation between temporal color mixing and spatial color mixing needs to be reduced linearly;

[0137] When the value interval of a is equal to 1, it means that the brightness of the conversion between temporal color mixing and spatial color mixing is equal;

[0138] When the value range of a is greater than 1, it means that the brightness of the conversion between temporal color mixing and spatial color mixing needs to increase linearly.

[0139] Based on the above design of the present invention, several application examples are provided below according to different application scenarios for reference by those skilled in the art:

[0140] In order to realize an active square display screen that needs to be displayed outdoors, its q value should be as large as possible, and in extreme cases it can be 1.

[0141] Example 2 In order to realize a two-subframe display method with high refresh rate and high color mixing efficiency, such as a partitioned color mixing display method based on complementary color mixing, n should be set to 2, and a pair of complementary primary colors should be selected, and t k Similarly, the weighted algorithm for backlight driving is then selected as needed.

[0142] Example 3 uses a six-primary color display solution based on ultra-large color gamut partitioning technology of mini-LED backlight as an example. S can be magenta, red, yellow, green, cyan, and blue. The size of current light-emitting chips is getting smaller and smaller. If a light source with multiple primary colors can be realized, then the mixing of multiple primary colors can be used to expand the existing RGB color gamut and achieve ultra-large color gamut display.

[0143] With reference to the accompanying drawings, the design results of the embodiments of the present invention are summarized as follows:

[0144] The embodiment of the present invention combines the liquid crystal display method of complementary color frame subtraction and partition color matching technology, and the process of converting spatial color mixing and temporal color mixing is as follows: Figure 1 As shown, when using traditional spatial color mixing technology, the three RGB sub-pixels emit light simultaneously to complete the color and brightness presentation. After converting to temporal color mixing, one sub-pixel and one sub-frame respectively display the corresponding color in three very short periods of time to complete the color and brightness presentation. Only one sub-pixel is needed to realize the image presentation, which means that when the sub-pixel size remains unchanged, the display method of the present invention can achieve ultra-high resolution display that is three times higher than that of traditional displays.

[0145] The embodiment of the present invention provides a liquid crystal display method combining complementary color frame reduction and partition color matching technology. The overall process in a specific application process can be as follows: Figure 2As shown, the computer first processes the image data using the algorithm of the present invention and related algorithms for liquid crystal transmittance, obtaining the image's liquid crystal transmittance and backlight brightness and color data. Further debugging and parameter determination are then performed using a molecular frame time mixing method.

[0146] The embodiment of the present invention provides a liquid crystal display method combining complementary color frame reduction and partition color matching technology, wherein the combination of partition color matching is as follows: Figure 3 As shown, the resolution of the LCD screen is i*j*m*n, there are m rows and n columns in partition a, and each partition has an RGBLED light source that can display various colors.

[0147] The embodiment of the present invention provides a liquid crystal display method combining complementary color frame subtraction and partition color matching technology, and the gamma correction process is as follows: Figure 4 As shown, gamma correction is used to adjust the brightness of the screen backlight to better suit the viewing needs of the human eye.

[0148] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any other manner. Any person skilled in the art may utilize the above-disclosed technical content to modify or modify the present invention into equivalent embodiments. However, any simple modifications, equivalent variations, and modifications to the above embodiments that do not depart from the technical content of the present invention and are based on the technical essence of the present invention remain within the scope of protection of the present invention.

[0149] This patent is not limited to the above-mentioned best implementation method. Anyone can derive various other forms of partition color adjustment methods based on the principles of spatial color mixing and temporal color mixing conversion under the inspiration of this patent. All equal changes and modifications made within the scope of the patent application of this invention should be covered by this patent.

Claims

1. A partition color adjustment method based on the principle of spatial color mixing and temporal color mixing conversion, characterized in that: By making the spatial color mixing effect equivalent to the light emission effect based on time color mixing, the spatial color mixing and time color mixing light intensity conversion function relationship is obtained, and multiple primary colors are displayed in turn based on the time color mixing principle to perform backlight zone color adjustment control; According to the principle of time color mixing, a frame of image is divided into a corresponding number of single primary color subframes according to the number of primary colors. When the primary color subframes are displayed in a certain order and the refresh frequency meets the requirements, and the luminous brightness of the single primary color in the corresponding display area is equal, it is equivalent to direct mixing of the primary color lights. In a single primary color subframe, the luminance of a single pixel has the following relationship: （1） Among them, S represents a primary color, Y S Indicates the final brightness of the single primary color S when mixing colors in space, Y S ' is the final brightness of the single primary color S in time mixing, a is the proportional coefficient, which is a positive constant; n is the total number of subframes corresponding to the time mixing method when the single primary color is used; k is the subframe number, 1≤k≤n; Y k is the backlight brightness of the kth subframe; is the liquid crystal transmittance in the kth subframe; t k is the backlight on time in the kth subframe; T S is the total time of the S primary color subframe; q is the ratio of the backlight on time to the total time in a single primary color subframe, that is, the backlight duty cycle corresponding to the S primary color subframe; When the t of each single primary color subframe k When consistent, the following expressions are related to time mixing: （2） Formula (2) is used to realize the brightness of a single primary color of a pixel based on the principle of time mixing; Turn-on time t of single primary color sub-frame backlight k The different value implementation methods of are as follows: 1) Same, indicating that each single-primary-color subframe has the same time; 2) Different, press The subframe time is divided in this way, and 1≤ ≤ ; The ratio of each subframe lighting time is: , n is in the range of [1, 100]; 3) Different, according to the different spectral viewing rates of the three primary colors of red, green and blue Adapt and determine the corresponding red, green and blue primary colors Proportion; For the mapping relationship between the image data and the light source data of the backlight in the partition color adjustment, consider that formula (2) is established for each pixel, assuming that the number of pixels corresponding to a single backlight partition is , corresponding to the kth subframe, the light output brightness of each pixel corresponding to a single backlight partition satisfies the following relationship: The following equation holds true for a single primary color S: （8） in Represents the time-mixed backlight brightness matrix of the entire partition, indicating the brightness of each pixel in the partition, and Indicates that the coordinates relative to partition a are The time-mixed backlight brightness of the pixel; Indicates that the coordinates relative to partition a are The backlight brightness of the spatial color mixing of the pixels; Indicates that the coordinates relative to partition a are The liquid crystal transmittance of the pixel; and because the backlight intensity in a single partition is the same due to the partition color adjustment, and a single partition has pixels, so the brightness of a single backlight partition after the liquid crystal is obtained by weighted calculation of the displayed image data: （9） Represents the brightness data of a single backlight partition RGBLED driver; The backlight brightness matrix of a single partition represents the backlight brightness value of each pixel in the entire partition; Represents the brightness of each pixel as a function f; The conversion process of display image data stream to LED light intensity data adopts gamma correction; the LED light intensity data after gamma correction is: （10） in This is the LED light intensity data after gamma correction; the value range of γ is between 0.1 and 100.

2. The method for color grading by partitioning based on the principle of spatial color mixing and temporal color mixing conversion according to claim 1, characterized in that: For a three-primary color liquid crystal display, the three primary color luminance expressions are: （3） in, 、 、 are the luminance components of the kth subframe corresponding to the red, green, and blue subframes respectively.

3. The method for color grading by partitioning based on the principle of spatial color mixing and temporal color mixing conversion according to claim 1 or 2, characterized in that: The color adjustment method adopted is: adjustment based on the time duty cycle q; within a single primary color subframe, by adjusting the ratio q of the backlight on time of each backlight partition to the total time, the light intensity of each backlight partition within the single primary color subframe is adjusted; by superimposing the modulation effects of other primary color subframes, the light intensity and light color of each liquid crystal backlight partition are modulated separately.

4. The method for color grading by partitioning based on the principle of spatial color mixing and temporal color mixing conversion according to claim 2, characterized in that: The color adjustment method adopted is: adjusting according to the light source with adjustable brightness of the three primary colors of RGB; in different primary color subframes, the brightness is modulated by using the adjustable light source in the backlight partition.

5. The method for color grading by partitioning based on the principle of spatial color mixing and temporal color mixing conversion according to claim 1, characterized in that: According to formula (2), the method for adjusting the light output brightness of a single pixel in a single primary color subframe is as follows: the light output brightness of the pixel in the single primary color subframe is achieved by modulating the transmittance of the pixel molecule and the light output brightness of the corresponding backlight partition, or by adjusting the backlight on duty cycle q and the number of subframes n of the primary color.

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