Temporal color mixing principle-based display method for pre-lighting frame reduction image synthesis

Abstract

Disclosed in the present invention is a temporal color mixing principle-based display method for pre- lighting frame reduction image synthesis. When using the temporal color mixing principle, three sub-frames need to be continuously displayed for one cycle to reproduce an original color image, and by means of a pre-lighting method, the original color image can be reproduced by only using one to two sub-frames for one cycle. The pre-lighting frame reduction image synthesis method can significantly reduce the number of frames required for the synthesis.

Description

A display method for pre-fill light frame-subtraction image synthesis based on time color mixing principle Technical Field

[0001] The present invention relates to the technical field of liquid crystal display, and in particular to a display method for pre-fill light frame-subtraction image synthesis based on the principle of temporal color mixing. Background Art

[0002] Temporal color mixing is a display technology that displays monochrome images in a time-sequential, high-speed sequence, overlaying three consecutive red, green, and blue monochrome images to create a color image. One such technology, called Field Sequential Color (FSC), implements this by first turning on all red backlights to illuminate the corresponding grayscale pattern, then turning on all green backlights to illuminate the corresponding grayscale pattern, and finally turning on all blue backlights to illuminate the corresponding grayscale pattern. The three consecutively displayed red, green, and blue monochrome images are then superimposed to create the final color image. Technical issues

[0003] At any given time, the backlight of FSC technology is fixed to one of the three colors: red, green, and blue. For any image, FSC technology requires three consecutive frames to synthesize. This has the disadvantages of fixed colors and a high number of frames required for synthesis. Technical Solutions

[0004] The technical solution adopted in the present invention is:

[0005] (1) First, according to the principle of temporal color mixing, the color image to be displayed is obtained from the input video, and the single color image is decomposed into three monochrome images of red, green and blue. The three monochrome images are reordered in a fixed order (such as green-red-blue) or according to the influence calculation formula according to their influence on the color image, and then further separated into three groups of monochrome light source luminous intensity values ​​and their corresponding grayscale patterns. Among them, the luminous intensity of the first color light source is A and its corresponding grayscale pattern is X, the luminous intensity of the second color light source is B and its corresponding grayscale pattern is Y, and the luminous intensity of the third color light source is C and its corresponding grayscale pattern is Z. Then the color image can be expressed in the form of (A×X)+(B×Y)+(C×Z). The original color image can be reproduced by continuously displaying three subframes in a cycle.

[0006] (2) Then, the second monochrome image (B×Y) can be decomposed. The portion of the first color grayscale pattern X illuminated by the partial light intensity nB of the second color is (nB×X), where the intensity of nB is controlled so that when illuminating the grayscale pattern X, any image point thereof does not exceed the corresponding value of the second monochrome image (B×Y). The decomposed (nB×X) is deducted from the second monochrome image (B×Y), and the remaining portion is (B×(Y-nX)), that is, the grayscale pattern (Y-nX) is illuminated by the light intensity B of the second color light source. A small conclusion is drawn that the grayscale pattern X is first illuminated by the second color light intensity nB, and then the grayscale pattern (Y-nX) is illuminated by the second color light intensity B. The original second monochrome image (B×Y) can be reproduced by continuously displaying two subframes in a cycle.

[0007] (3) Finally, the third monochrome image (C×Z) can be decomposed into the portion (mC×X) where the third color partial light intensity mC illuminates the first color grayscale pattern X, where the mC light intensity is controlled so that when illuminating the grayscale pattern X, any image point does not exceed the corresponding value of the third monochrome image (C×Z). It can also be further decomposed into the portion (pC×(Y-nX)) where the third color partial light intensity pC illuminates the second color grayscale pattern (Y-nX), where the pC light intensity is controlled so that when illuminating the grayscale pattern (Y-nX), any image point does not exceed the corresponding value of the third monochrome image (C×Z) after deducting the (mC×X) grayscale pattern. The third monochrome image (C×Z) can be decomposed into the (mC×X) portion, and then into the (pC×(Y-nX)) portion, leaving the (C×(Z-mX-pY+npX)) portion. A small conclusion is drawn: first use the third color mC light intensity to illuminate the grayscale pattern X, then use the third color pC light intensity to illuminate the grayscale pattern (Y-nX), and finally use the third color C light intensity to illuminate the grayscale pattern (Z-mX-pY+npX). The original third monochrome image (C×Z) can be reproduced by continuously displaying three subframes in a cycle.

[0008] (4) The pre-fill light subtraction image synthesis method of the present invention is used. In the first subframe of each display cycle, the first color grayscale pattern X is first illuminated with the first color light intensity A to fully display the first monochrome image (A×X). At the same time, partial light intensity nB of the second color is used for pre-fill light illumination to display a portion of the second image (nB×X). At the same time, partial light intensity mC of the third color is used for pre-fill light illumination to display a portion of the third image (mC×X). Using the pre-fill light method, an image ((A+nB+mC)×X) can be displayed in the first subframe of each display cycle; when the grayscale pattern Y and the grayscale pattern Z are both equal to 0 or are proportional to the grayscale pattern X, only one subframe is needed to complete the entire cycle to reproduce the original color image. For example, to display a golden sun, only (green light + red light) needs to be used to illuminate the sun-shaped grayscale pattern, and the original golden sun image can be reproduced with only one subframe.

[0009] (5) When a subframe cannot complete the entire cycle to reproduce the original color image, in the second subframe of the display cycle, the second color intensity B is first used to illuminate the second color grayscale pattern (Y-nX), and the second monochrome image (B×Y) is fully displayed using two subframes. At the same time, partial light intensity pC of the third color is used for pre-fill lighting, and a portion of the third image (pC×(Y-nX)) is displayed. Using the pre-fill lighting method, an image ((B+pC)×(Y-nX)) can be displayed in the second subframe of each display cycle. When the grayscale pattern Z is equal to 0 or is proportional to the grayscale pattern (Y-nX), only two subframes are needed to complete the entire cycle to reproduce the original color image. For example, to display a golden sun with purple eyes, only (red light + blue light) needs to be used in the second subframe to illuminate the eye-shaped grayscale pattern, and only two subframes are needed to reproduce the original golden sun image with purple eyes.

[0010] (6) When two subframes cannot complete the entire cycle to reproduce the original color image, if the residual third color C light intensity illuminates the grayscale pattern (Z-mX-pY+npX) with too little information, it can be directly added to the next cycle of color image for processing. If the display refresh rate is fast enough, the human eye cannot distinguish the difference. If the residual information is large, the third subframe can be used for display, and the pre-fill method can be used to fill in part of the image of the next cycle. Beneficial effects

[0011] The pre-fill light frame-subtraction image synthesis method of the present invention can reduce the original color image reproduction method of using the time mixing principle to continuously display three sub-frames in a cycle to only 1-2 frames. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The accompanying figure is a schematic diagram of the final golden sun image with purple eyes synthesized from the golden sun image of the first subframe and the purple eye image of the second subframe.

[0013] In the first subframe on the left, the first green sub-light source illuminates the corresponding sun-shaped grayscale pattern, and the second red sub-light source is turned on to pre-fill the sun-shaped grayscale pattern to synthesize a golden sun image.

[0014] In the second middle subframe, the second red sub-light source illuminates the corresponding eye-shaped grayscale pattern, and the third blue sub-light source is turned on to pre-fill the eye-shaped grayscale pattern to synthesize a purple eye image.

[0015] Reference numerals: 1: liquid crystal panel sub-pixel; 2: sun-shaped grayscale pattern; 3: eye-shaped grayscale pattern; 4: first color sub-light source; 5: second color sub-light source; 6: third color sub-light source. Best Mode for Carrying Out the Invention

[0016] Example 1:

[0017] Embodiment 1 of the present invention provides a liquid crystal display method based on the principles of optical isolation and partitioning and temporal color mixing, which is described by taking a specific implementation as an example.

[0018] (1) When selecting a 1600*1200 resolution, high refresh rate, color filter-free LCD panel, a reflective cup array plate with 25 horizontal and 19 vertical reflective cups is molded out of an iron-nickel-cobalt Kovar alloy sheet with a thermal expansion coefficient close to that of the LCD panel. The reflective cup array plate is mounted on a color LED backlight array plate. Each individual rectangular reflective cup in the reflective cup array plate covers a display area of ​​64*64 pixels. The color LED backlight array plate is configured using a method for achieving color backlight luminescence balance and improving luminous intensity, which is implemented as step A.

[0019] (2) Optical films such as diffusion films, BEF prism films, and DBEF birefringent films with light-homogenizing and brightness-enhancing effects are installed on the molded reflective cup array board. Finally, a high-refresh rate, color-filter-free liquid crystal panel is installed on the optical film. The reflective cup array board can be used to partition the liquid crystal display area, and any partition is optically isolated from the other partitions. By using the optical isolation partitioning method, the color and brightness of the color light source in the partition can be independently adjusted without affecting other adjacent partitions.

[0020] (3) By collecting the VSYNC frame synchronization signal or the DE display data enable signal generated by the display video signal, the backlight control counter is triggered to record the video signal CLK clock cycle, which continues until the first row scan line of the next frame starts to update the display. The delay time is calculated based on the total number of video signal CLK clocks recorded during this period, the row scan line position is determined, and the color and brightness of the color light source in the corresponding optical isolation partition are updated.

[0021] (4) For the color backlight source and the high refresh rate color filter-free liquid crystal panel in the optical isolation partition, an energy-saving display method based on the synchronous adjustment of the color backlight and grayscale pattern of the optical isolation partition is used to perform energy-saving optimization, which is implemented as step B.

[0022] (5) A display method of pre-fill light subtraction image synthesis based on the principle of time color mixing is used as step C to complete the final color picture display. Modes for Carrying Out the Invention

[0023] Example 2:

[0024] A second embodiment of the present invention provides a method for achieving balanced color backlighting and increasing luminous intensity. This method can be applied to the liquid crystal display method based on optical isolation, zoning, and temporal color mixing principles provided in the first embodiment, as a specific implementation of step A. Furthermore, this method for achieving balanced color backlighting and increasing luminous intensity can also be performed independently to increase the driving current share of the green and blue sub-light sources, significantly improving the average driving current and luminous intensity of the sub-light sources. This embodiment uses the independent implementation as an example for illustration.

[0025] (1) Select a 3030 packaged RGB-LED lamp as the red, green, and blue light source, and replace the blue LED chip with a red LED chip as the red, green, and red light source. The maximum current limit for each chip is 20mA. When the red chip is supplied with 18mA, the green chip with 13.5mA, and the blue chip with 4.5mA, the RGB-LED lamp emits white light with a color temperature of 6500K. The average current per chip is 12mA, and the average luminous intensity of each LED lamp is 2.85cd.

[0026] (2) The backlight micro unit is composed of two red, green and blue light sources and two red, green and red light sources arranged alternately, where the ratio of blue: green: red LED chips is 1:2:3.

[0027] (3) Hardware low blue light is achieved by using blue LED chips with a main wavelength of 460nm.

[0028] (4) All red sub-light sources in the backlight micro-unit are connected in series and driven individually, all green sub-light sources in the backlight micro-unit are connected in series and driven individually, and all blue sub-light sources in the backlight micro-unit are connected in series and driven individually.

[0029] (5) Use several backlight micro units to arrange into a complete color backlight.

[0030] (6) In the process of achieving color backlight luminescence balance, when the target is standard white light with a color temperature of 6500K, according to the method of using all red, green and blue light sources, the solution of 4 RGB-LED lights in a single backlight micro-unit has an average current of 12mA per chip and a luminous intensity of 11.4cd per backlight micro-unit; using the solution of 2 red, green and blue light sources and 2 red, green and red light sources in a single backlight micro-unit, the red chip has an 18mA current, the green chip has a 20mA current, and the blue chip has a 13.5mA current, with an average current of 18mA per chip and a luminous intensity of 17.1cd per backlight micro-unit; experiments have shown that using this method to achieve color backlight luminescence balance and improve luminous intensity can increase the average current of the sub-light source by 50% under the same maximum driving current limit of the sub-light source, thereby increasing the luminous intensity by 50%. Example

[0031] A third embodiment of the present invention provides an energy-saving display method for synchronously adjusting a color-separated backlight and a grayscale pattern based on optically isolated zoning. This method can be applied to the liquid crystal display method based on optically isolated zoning and temporal color mixing principles provided in the first embodiment, as a specific implementation of step B. Furthermore, this energy-saving display method for synchronously adjusting a color-separated backlight and a grayscale pattern based on optically isolated zoning can also be performed independently. By synchronously adjusting the color-separated backlight and the grayscale pattern, energy savings can be achieved while maintaining the same display. This embodiment uses the independent method as an example for illustration.

[0032] (1) When selecting a 1600*1200 resolution LCD panel, a reflective cup array plate with 25 horizontal and 19 vertical reflective cups is molded out of an iron-nickel-cobalt Kovar alloy sheet with a thermal expansion coefficient close to that of the LCD panel. The reflective cup array plate is then mounted on a color LED backlight array panel. Each individual rectangular reflective cup in the reflective cup array plate covers a display area of ​​64*64 pixels. Then, optical films such as a diffusion film, a BEF prism sheet, and a DBEF birefringent sheet with light-homogenizing and brightening effects are mounted on the molded reflective cup array plate. Finally, the LCD panel is mounted on the optical film. The reflective cup array plate can be used to partition the LCD display area, and any partition is optically isolated from the other partitions. By using the optical isolation partitioning method, the color and brightness of the color light source in the partition can be independently adjusted without affecting other adjacent partitions.

[0033] (2) The main controller inside the display decodes the video signal sent by the host computer to the display and separates the 64*64 pixel color display image corresponding to each reflector cup in the next frame. It then searches for the maximum grayscale level of the sub-pixel corresponding to the sub-light source within the optical isolation partition. The maximum grayscale level of the sub-pixel corresponding to the red sub-light source is 127; the maximum grayscale level of the sub-pixel corresponding to the green sub-light source is 63; and the maximum grayscale level of the sub-pixel corresponding to the blue sub-light source is 192.

[0034] (3) Because the grayscale range displayed by the LCD panel is 0-255, the upper limit of the grayscale range of the LCD panel is divided by the maximum value of the grayscale levels of the three sub-pixels, and the magnification corresponding to red is 2 times, the magnification corresponding to green is 4 times, and the magnification corresponding to blue is 1.33 times.

[0035] (4) The grayscale levels of all sub-pixels corresponding to the red sub-light source in the optical isolation partition are increased to 2 times, and the luminous intensity of the red sub-light source is reduced to 1 / 2. The 64*64 grayscale pattern with a grayscale level of 0-127 is illuminated by a 100% brightness backlight. The display effect is the same as that of the 64*64 grayscale pattern with a grayscale level of 0-255 using a 50% brightness backlight. Therefore, by synchronously adjusting the color separation backlight and the grayscale pattern, a 50% energy saving effect can be achieved without changing the display.

[0036] (5) Similarly, the grayscale levels of all sub-pixels corresponding to the green sub-light source in the optical isolation partition are increased to 4 times, and the luminous intensity of the green sub-light source is reduced to 1 / 4. A 100% brightness backlight is used to illuminate a 64*64 grayscale pattern with a grayscale level of 0-63. The display effect is the same as that of a 25% brightness backlight to illuminate a 64*64 grayscale pattern with a grayscale level of 0-255. By synchronously adjusting the color separation backlight and the grayscale pattern, a 75% energy saving effect can be achieved without changing the display.

[0037] (6) Similarly, the grayscale levels of all sub-pixels corresponding to the blue sub-light source in the optical isolation partition are increased to 1.33 times, and the luminous intensity of the blue sub-light source is reduced to 75%. The 64*64 grayscale pattern with a grayscale level of 0-192 is illuminated by a 100% brightness backlight. The display effect is the same as that of the 64*64 grayscale pattern with a grayscale level of 0-255 using a 75% brightness backlight. By synchronously adjusting the color separation backlight and the grayscale pattern, a 25% energy saving effect is achieved without changing the display.

[0038] Taking various situations into consideration, the use of this energy-saving display method based on optical isolation partitioning, color backlight and grayscale pattern synchronous adjustment can save an average of about 50% energy while keeping the display unchanged. Example

[0039] A fourth embodiment of the present invention provides a display method for pre-fill light subtraction frame image synthesis based on the principle of temporal color mixing. This method can be applied to the liquid crystal display method based on optical isolation and zoning and temporal color mixing provided in the first embodiment, as a specific implementation of step C. Furthermore, this display method for pre-fill light subtraction frame image synthesis based on the principle of temporal color mixing can also be performed independently, reducing the original color image reproduction method using the principle of temporal color mixing, which requires a fixed, continuous display of three subframes in a cycle, to only one or two frames. This embodiment uses the independent method as an example for illustration.

[0040] (1) The main controller inside the display decodes the video signal sent by the host computer to the display and separates the next frame of 64*64 pixel color display image. The image content is the image of a golden sun with purple eyes.

[0041] (2) Decompose a single color image into three monochrome images of red, green and blue. The three monochrome images are rearranged in a fixed order of green-red-blue according to their influence on the color image.

[0042] (3) The three monochrome images are further decomposed into a grayscale pattern in the shape of a sun illuminated by green light, a grayscale pattern in the shape of a sun with eyes illuminated by red light, and a grayscale pattern in the shape of an eye illuminated by blue light.

[0043] (4) Using the pre-fill light frame-reduction image synthesis method of the present invention, in the first subframe of the current display cycle, 100% green light is used to illuminate the sun-shaped grayscale pattern, and the entire green monochrome image is displayed. At the same time, 100% red light is used for pre-fill light, illuminating the sun-shaped grayscale pattern, and partially displaying the red monochrome image. At the same time, the calculation results show that the sun-shaped grayscale pattern has nothing to do with blue, and the blue light brightness is 0 and no pre-fill light is performed. Assuming that the image content is a golden sun image, to display the golden sun, it is only necessary to illuminate the sun-shaped grayscale pattern with (green light + red light), and the original golden sun image can be reproduced with only one subframe.

[0044] (5) Using the pre-fill light and frame-subtraction image synthesis method of the present invention, in the second subframe of the current display cycle, 100% red light is used to illuminate the eye-shaped grayscale pattern. Together with the sun-shaped grayscale pattern already displayed in the first subframe, the red monochrome image is fully displayed. At the same time, 100% blue light is used for pre-fill light to illuminate the eye-shaped grayscale pattern, displaying a blue monochrome image. The first subframe already displays a golden sun. To further display a golden sun with purple eyes, it is only necessary to use (red light + blue light) to illuminate the eye-shaped grayscale pattern in the second subframe. The original golden sun image with purple eyes can be reproduced using only two subframes. Industrial Applicability

[0045] The pre-fill light frame-subtraction image synthesis method of the present invention uses only software recalculation, which can reduce the method of reproducing the original color image by continuously displaying three sub-frames in a cycle based on the principle of time mixing to only 1-2 frames. Sequence Listing Free Content

[0046] Unordered list.

Claims

1. A display method for pre-fill light subtraction frame image synthesis based on the principle of temporal color mixing, characterized in that: The method comprises the following steps: First, according to the principle of temporal color mixing, the color image to be displayed is obtained from the input video, and the single color image is decomposed into three monochrome images of red, green and blue. The three monochrome images are reordered in a fixed order (e.g., green-red-blue) or according to the influence calculation formula according to their influence on the color image, and then further separated into three groups of monochrome light source luminous intensity values ​​and their corresponding grayscale patterns. Where the luminous intensity of the first color light source is A and its corresponding grayscale pattern is X, the luminous intensity of the second color light source is B and its corresponding grayscale pattern is Y, and the luminous intensity of the third color light source is C and its corresponding grayscale pattern is Z, then the color image can be expressed in the form of (A×X)+(B×Y)+(C×Z), and the original color image can be reproduced by displaying three subframes in a cycle. Then, the second monochrome image (B×Y) can be disassembled, and the part of the first color grayscale pattern X illuminated by the partial light intensity nB of the second color is (nB×X), where the light intensity of nB is controlled so that any image point does not exceed the corresponding value of the second monochrome image (B×Y) when irradiating the grayscale pattern X. The second monochrome image (B×Y) is deducted from the decomposed (nB×X), and the remaining part is (B×(Y-nX)), that is, the grayscale pattern (Y-nX) is illuminated by the luminous intensity B of the second color light source. Finally, the third monochrome image (C×Z) can be decomposed, and the part of the first color grayscale pattern X illuminated by the partial light intensity mC of the third color is (mC×X), where the light intensity of mC is controlled so that when irradiating the grayscale pattern X, any image point does not exceed the corresponding value of the third monochrome image (C×Z). It can also be further decomposed, and the part of the second color grayscale pattern (Y-nX) is illuminated by the partial light intensity pC of the third color is (pC×(Y-nX)), where the light intensity of pC is controlled so that when irradiating the grayscale pattern (Y-nX), any image point does not exceed the corresponding value of the third monochrome image (C×Z) after deducting the grayscale pattern (mC×X). The third monochrome image (C×Z) can be decomposed into (mC×X) parts, and then into (pC×(Y-nX)) parts, with the remaining (C×(Z-mX-pY+npX)) parts. The pre-fill light frame-reduction image synthesis method of the present invention is used, and in the first subframe of each display cycle, the first color grayscale pattern X is first illuminated with the light intensity A of the first color, and the first monochrome image (A×X) is completely displayed. At the same time, partial light intensity nB of the second color is used for pre-fill light, and part of the second image (nB×X) is displayed. At the same time, partial light intensity mC of the third color is used for pre-fill light, and part of the third image (mC×X) is displayed. Using the pre-fill light method, an image of ((A+nB+mC)×X) can be displayed in the first subframe of each display cycle. When the grayscale pattern Y and the grayscale pattern Z are both equal to 0 or proportional to the grayscale pattern X, only one subframe is needed to complete the entire cycle and reproduce the original color image. For example, to display a golden sun, only (green light + red light) needs to be used to illuminate the sun-shaped grayscale pattern to reproduce the original golden sun image with only one subframe.When one subframe cannot complete the entire cycle to reproduce the original color image, then in the second subframe of the display cycle, the second color light intensity B is first used to illuminate the second color grayscale pattern (Y-nX), and the second monochrome image (B×Y) is fully displayed using two subframes. At the same time, partial light intensity pC of the third color is used for pre-fill lighting, and part of the third image (pC×(Y-nX)) is displayed. Using the pre-fill lighting method, an image of ((B+pC)×(Y-nX)) can be displayed in the second subframe of each display cycle. When the grayscale pattern Z is equal to 0 or is proportional to the grayscale pattern (Y-nX), only two subframes are needed to complete the entire cycle to reproduce the original color image. For example, to display a golden sun with purple eyes, it is only necessary to use (red light + blue light) to illuminate the eye-shaped grayscale pattern in the second subframe to reproduce the original golden sun image with purple eyes using only two subframes. When two subframes cannot complete the entire cycle to reproduce the original color image, if the residual third color C light intensity irradiation grayscale pattern (Z-mX-pY+npX) has too little information, it can be directly added to the next cycle of color image for processing. If the display refresh rate is fast enough, the human eye cannot distinguish the difference. If the residual information is large, the third subframe can be used for display, and the pre-fill light method can be used to fill in part of the image of the next cycle.

2. The method according to claim 1, characterized in that The influencing factors of the influence calculation formula include the sensitivity of different colors to the human eye (green 0.7, red 0.2, blue 0.1), the average grayscale level of all sub-pixels corresponding to the three basic colors of red, green and blue, and the luminous intensity of the three basic color light sources of red, green and blue. The three are multiplied together according to the same or different weights as the influence calculation formula.

3. The method according to claim 1, characterized in that The first part that can be decomposed from the second monochrome image (B×Y) can have a partial light intensity of the second color when actually used that is less than or equal to the nB value; similarly, the first part that can be decomposed from the third monochrome image (C×Z) can have a partial light intensity of the third color when actually used that is less than or equal to the mC value; Similarly, the third color partial light intensity of the second part decomposed from the third monochrome image (C×Z) in actual application may be less than or equal to the pC value.

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