Color shift compensation method and compensation system

Abstract

The present application discloses a color deviation compensation method and compensation system for a display panel. The compensation method includes: collecting a pure grayscale image displayed by a display panel based on a preset grayscale value; obtaining multiple channel component values ​​of each pixel point according to the pure grayscale image; respectively obtaining compensation values ​​of multiple channels of each pixel point; and respectively compensating the component values ​​of the corresponding channels for each pixel point according to the compensation values ​​of the multiple channels, wherein the compensation values ​​of the multiple channels are calculated according to the difference between the component values ​​of the corresponding channels of each pixel point and the mean value of the component values ​​of the multiple channels of each pixel point in the reference area of ​​the pure grayscale image. The color deviation compensation method also includes: if the display image of the display panel after compensation does not achieve the expected effect, repeating the above steps until the display panel achieves the expected display effect; if the expected effect is achieved, storing the compensation values ​​of the multiple channels of each pixel point for color deviation compensation in the display stage.

Description

Technical Field

[0001] The present invention relates to the field of display technology, and in particular to a color deviation compensation method and a compensation system for compensating a display panel. Background Art

[0002] With the development of display technology, the application of display panels is becoming more and more extensive, and the requirements for the display effect of display panels are also getting higher and higher. During the production process of display panels, due to production processes and other reasons, display panels will produce Mura phenomenon. Mura phenomenon refers to the phenomenon that the brightness displayed by the display panel is uneven, causing various traces.

[0003] The manifestation of color shift Mura in brightness is that the light intensity ratio of the RGB primary colors in the color shift area is inconsistent with the required ratio of white light. In the existing technical solutions, there are two main solutions for compensating color shift Mura: one is white screen monochrome compensation, that is, shooting the white screen with a camera and processing it to obtain compensation data for compensation, but this method cannot avoid the color shift phenomenon caused by the display panel process (such as the uniformity deviation of OLED panel evaporation) during the white screen monochrome compensation, and cannot ensure the reliability of the compensation result; the other is RGB three-color compensation, that is, using a camera to shoot the red, green, and blue screens at different grayscales, and calculate the compensation values ​​for compensation, but this method takes a long time to shoot, has high requirements for camera calibration, and cannot avoid color crosstalk between Camera-RGB and grayscale images, resulting in errors in the calculated compensation values, making some panels still appear to have color shift. Summary of the invention

[0004] In view of the above problems, an object of the present invention is to provide a color cast compensation method and a compensation system for compensating a display panel.

[0005] According to one aspect of the present application, a method for compensating for color deviation of a display panel is provided, comprising a plurality of steps: acquiring a pure grayscale image displayed by the display panel based on a preset grayscale value; obtaining component values ​​of multiple channels of each pixel point according to the pure grayscale image; respectively obtaining compensation values ​​of the multiple channels of each pixel point in the pure grayscale image; and for each pixel point, respectively compensating the component values ​​of the corresponding channels according to the compensation values ​​of the multiple channels, wherein the compensation values ​​of the multiple channels are calculated according to the difference between the component values ​​of the corresponding channels of each pixel point and the mean values ​​of the component values ​​of the multiple channels of each pixel point in a reference area in the pure grayscale image, and the method for compensating for color deviation further comprises: if the displayed image of the display panel after compensation does not achieve the expected effect, repeating the plurality of steps until the displayed image of the display panel achieves the expected effect; if the displayed image of the display panel after compensation achieves the expected effect, storing the compensation values ​​of the multiple channels of each pixel point for use in compensating for color deviation in the display stage.

[0006] Optionally, the component values ​​of the multiple channels are R, G, and B channel component values ​​of the pure grayscale image in an RGB color system.

[0007] Optionally, obtaining the compensation values ​​of the multiple channels of each pixel in the pure grayscale image includes: acquiring chromaticity information and brightness information of each pixel according to the pure grayscale image data; calculating component values ​​of the X, Y, and Z channels of each pixel in the XYZ color system according to the chromaticity information and brightness information; and calculating the R, G, and B channel component values ​​of each pixel in the RGB color system according to the component values ​​of the X, Y, and Z channels.

[0008] Optionally, the color deviation compensation method also includes: selecting a minimum number of repetitions; and compensating the multiple display panels with the minimum number of repetitions, and when the number of display panels that fail to achieve the expected effect exceeds an expected number, reselecting the minimum number of repetitions, wherein by executing the multiple steps with the minimum number of repetitions, the displayed image of the display panel after compensation achieves the expected effect, thereby reducing the compensation time.

[0009] Optionally, selecting the minimum number of repetitions includes: comparing the pure grayscale image displayed by the display panel before compensation and after the Nth compensation; if the difference in display effect of the display panel before compensation and after the Nth compensation is lower than a set requirement, taking N as the minimum number of repetitions, where N is a positive integer greater than or equal to 1.

[0010] Optionally, selecting the minimum number of repetitions includes: comparing the pure grayscale image displayed by the display panel after the Mth compensation and the M+1th compensation, if the difference in display effect of the display panel after the Mth compensation and the M+1th compensation is lower than the set requirement, then taking M as the minimum number of repetitions, where M is a positive integer greater than or equal to 1.

[0011] Optionally, the expected number is one.

[0012] Optionally, the reference area is a central area of ​​the pure grayscale image.

[0013] Optionally, the preset grayscale value is 2-4 different grayscale values.

[0014] Optionally, the display panel is one of LCD, OLED, and MicroLED.

[0015] According to another aspect of the present application, a color deviation compensation system for a display panel is provided, comprising: a display panel, for displaying a pure grayscale image at a preset grayscale value according to driving data; a driving module, connected to the display panel, for providing the driving data to the display panel; an acquisition device, for acquiring the pure grayscale image displayed by the display panel; a computer, connected to the acquisition device, for calculating compensation values ​​of the multiple channels of each pixel in the pure grayscale image as compensation data according to the pure grayscale image; and a flash memory, connected to the computer and the driving module, for storing the compensation values ​​of the multiple channels and providing them to the driving module, wherein the color deviation compensation system compensates for the color deviation of the display panel according to the color deviation compensation method according to any one of claims 1 to 10.

[0016] Optionally, the driving module also includes a compensation unit, and the driving module is configured to: provide the driving data to the display panel according to the grayscale data of the preset grayscale value, so that the display panel displays the pure grayscale image before compensation; and provide the driving data to the display panel according to the compensated grayscale data, so that the display panel displays the compensated grayscale image, wherein the compensation unit is used to superimpose the compensation data with the grayscale data of the preset grayscale value to obtain the compensated grayscale data.

[0017] According to the color deviation compensation method of the present invention, the chromaticity information and brightness information of each pixel in the grayscale image are obtained by photographing and processing pure grayscale images of different grayscale values ​​and converted into the component values ​​of the three channels of R, G, and B in the RGB color space, and the component values ​​of each pixel of the display screen are compensated based on the reference area data. The color deviation compensation method of the present invention only needs to photograph pure grayscale images under different grayscale values ​​to achieve RGB three-color compensation, avoiding the color deviation phenomenon caused by the display panel process when only monochrome compensation is performed on the white screen, and improving the reliability of compensation; at the same time, compared with the RGB three-color compensation of the prior art, the compensation method of the present invention can reduce the requirements for the camera, while reducing the production line photography time and improving production capacity. Furthermore, according to the compensation method of the present invention, the compensation effect can also be confirmed by repeated multiple times, so that the compensation effect is optimized. Furthermore, by selecting the minimum number of repetitions, the operation time can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The above and other objects, features and advantages of the present invention will become more apparent through the following description of the embodiments of the present invention with reference to the accompanying drawings, in which:

[0019] Figure 1 A schematic structural block diagram of a compensation system according to an embodiment of the present invention is shown;

[0020] Figure 2A schematic flow chart of a compensation method according to an embodiment of the present invention is shown;

[0021] Figure 3 Show Figure 2 A schematic flow chart of obtaining multiple channel component values ​​of each pixel is shown; DETAILED DESCRIPTION

[0022] The present invention will be described in more detail below with reference to the accompanying drawings. In each of the accompanying drawings, the same elements are represented by similar reference numerals. For the sake of clarity, the various parts in the accompanying drawings are not drawn to scale. In addition, some well-known parts may not be shown.

[0023] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the statement "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0024] Figure 1 This is a schematic structural block diagram of a compensation data acquisition system provided in an embodiment of the present application. Figure 1 The compensation data acquisition system 10 shown includes a computer 11 , a flash memory (Flash IC) 12 , an acquisition device 13 , a display panel 14 and a driving module 15 .

[0025] The driving module 15 is connected to the display panel 14, and provides driving data to the display panel according to the grayscale data of the preset grayscale value to drive the display panel 14 to display pure grayscale images under the preset grayscale value. In some embodiments, the driving module 15 drives the display panel 14 to display pure grayscale images under 2-4 different grayscale values, for example, grayscale images with four different grayscale values ​​of Gary32, Gary128, Gary192, and Gary255. In some embodiments, the display panel 14 is, for example, any one of LCD, OLED, or MicroLED. However, it should be understood that the number and grayscale value of pure grayscale images displayed by the display panel 14 of this embodiment should not be limited thereto. In the specific implementation process, technicians can select the number and grayscale value of grayscale images according to actual conditions.

[0026] In some embodiments, the acquisition device 13 is, for example, a camera, which is used to capture the pure grayscale image displayed on the display panel 14 and send the obtained image data to the computer 11 connected thereto. The computer 11 calculates compensation data based on the image data. In some embodiments, the computer 11 uses the central area of ​​the display panel 14 (i.e., A*B pixels in the central area of ​​the display panel) as a reference area, and compensates the component values ​​of the corresponding channels of other pixels relative to the mean value of the component values ​​of multiple channels of each pixel in the central area (for example, the mean value of the component values ​​of R, G, and B channels under the RGB color system) to calculate compensation values ​​as compensation data; in some other embodiments, the computer 11 can also use any position area in the display panel 14 as a reference area, and calculate compensation values ​​for other pixels relative to the mean value of the component values ​​of multiple channels of each pixel in the area (for example, the mean value of the component values ​​of R, G, and B channels under the RGB color system).

[0027] Furthermore, in some embodiments, the difference between the mean values ​​of each component value of the compensated point and the corresponding channel of the reference area is calculated as the compensation value; in some other embodiments, the ratio of the difference between the mean values ​​of each component value of the compensated point and the corresponding channel of the reference area to the mean values ​​of each component value of the reference area is calculated as the compensation value.

[0028] The flash memory 12 is connected to the computer 11 and the driving module 15 respectively, and the computer 11 stores the calculated compensation value in the flash memory 12 (Flash IC) matched with the display panel 14. The driving module 15 also includes a compensation unit 151, which is used to obtain compensated grayscale data by superimposing the compensation data in the flash memory 12 and the grayscale data of the preset grayscale value, and provide driving data to the display panel 14 according to the compensated grayscale data to drive the display panel 14 to display the compensated picture, thereby confirming the compensation effect.

[0029] Figure 2 A schematic flow chart of a color cast compensation method according to an embodiment of the present invention is shown, and the specific implementation steps are as follows:

[0030] S110: Acquiring a pure grayscale image displayed by the display panel based on a preset grayscale value;

[0031] In this step, the driving module 15 provides driving data to the display panel according to the grayscale data of the preset grayscale value to drive the display panel 14 to display pure grayscale images under the preset grayscale value. In some embodiments, the driving module 15 drives the display panel 14 to display pure grayscale images under 2-4 different grayscale values, for example, displaying pure grayscale images of four different grayscale values ​​of Gary32, Gary128, Gary192, and Gary255. The acquisition device 13 (for example, a camera in some embodiments) is used to acquire multiple pure grayscale images displayed by the display panel 14 and send the acquired image data to the computer 11. In some embodiments, the display panel 14 is, for example, any one of LCD, OLED or MicroLED. However, it should be understood that the number and grayscale value of the pure grayscale images displayed by the display panel 14 in this embodiment should not be limited thereto. In the specific implementation process, technicians can select the number and grayscale value of pure grayscale images according to actual conditions.

[0032] S120: Obtain component values ​​of multiple channels of each pixel according to the pure grayscale image:

[0033] In this step, the computer 11 processes the image data of the multiple pure grayscale images sent by the acquisition device 13 to obtain the component values ​​of the multiple channels of each pixel point, and executes step S130 after the component values ​​of the multiple channels of each pixel point.

[0034] For example, in some embodiments, see Figure 3 , taking obtaining R, G, and B channel component values ​​under the RGB color system as an example, the specific obtaining steps include S121, S122, and S123.

[0035] Step S121: Obtaining the chromaticity information and brightness information of each pixel according to the pure grayscale image data:

[0036] In this step, the computer 11 processes the image data acquired by the acquisition device 13 to obtain the color coordinates (x, y, lv) of each pixel, where x, y represent the chromaticity information of each pixel of the grayscale image; lv represents the brightness information.

[0037] Step S122: Calculate the component values ​​of the X, Y, and Z channels of each pixel in the XYZ color system according to the chromaticity information and the brightness information:

[0038] In this step, the computer 11 processes the color coordinates (x, y, lv) and obtains (X, Y, Z) data. In some embodiments, the calculation can be performed using the following formula:

[0039] X=x*Y / y (1)

[0040] Y=Lv (2)

[0041] Z=(1-XY)*Y / y (3)

[0042] Where x, y represent the chromaticity information of each pixel of the grayscale image; lv represents the brightness information, and X, Y, and Z represent the component values ​​of the X, Y, and Z channels in the XYZ color system (i.e., the three stimulus values ​​in the XYZ color system).

[0043] Step S123: Calculating the R, G, B channel component values ​​of each pixel in the RGB color system according to the component values ​​of the X, Y, Z channels;

[0044] In this step, the computer 11 processes (X, Y, Z) and obtains (R, G, B) data. In some embodiments, the calculation can be performed using the following formula:

[0045] R=3.2406*X / 100-1.5372*Y / 100-0.4986*Z / 100 (4)

[0046] G=-0.9689*X / 100+1.8758*Y / 100+0.0415*Z / 100 (5)

[0047] B=0.0557*X / 100-0.2040*Y / 100+1.0570*Z / 100 (6)

[0048] Among them, X, Y, Z as well as R, G, B respectively represent the component values ​​of each channel in the XYZ color system or the RGB color system (that is, the three stimulus values ​​under the XYZ color system and the RGB color system).

[0049] By way of example, steps S122 and S123 are further described in conjunction with two sets of (x, y, lv) data.

[0050] For example, when x=0.3024; y=0.3197; lv=553.39, combining equations (1), (2), and (3) yields X=523.444; Y=553.39; Z=654.132, and further combining equations (4), (5), and (6) yields R=5.19452; G=5.5803; B=6.07682.

[0051] For example, when x=0.2833; y=0.2995; lv=126.18, combining equations (1), (2), and (3) yields X=119.355; Y=126.18; Z=175.767, and further combining equations (4), (5), and (6) yields R=1.0518; G=1.2834; B=1.66693.

[0052] Step S130: respectively obtaining compensation values ​​of the multiple channels of each pixel in the pure grayscale image:

[0053] In this step, the computer 11 calculates the compensation values ​​of the multiple channels according to the difference between the component value of the corresponding channel of each pixel point and the mean value of the component value of the corresponding channel of the reference area in the pure grayscale image, and interpolates the unselected grayscale values ​​according to the compensation of the selected grayscale value to obtain all the compensation data.

[0054] In some embodiments, the computer 11 uses the central area of ​​the display panel 14 (i.e., A*B pixels in the central area of ​​the display panel) as a reference area, and compensates the component values ​​of the corresponding channels of other pixels relative to the average value of the component values ​​of multiple channels of each pixel in the central area (for example, the R, G, and B channel component values ​​under the RGB color system) to calculate compensation values ​​as compensation data; in some other embodiments, the computer 11 can also use any position area in the display panel 14 as a reference area, and calculates compensation values ​​for other pixels relative to the average value of the component values ​​of multiple channels of each pixel in the area (for example, the R, G, and B channel component values ​​under the RGB color system).

[0055] Furthermore, in some embodiments, the difference between the mean values ​​of each component value of the compensated point and the corresponding channel of the reference area is calculated as the compensation value; in some other embodiments, the ratio of the difference between the mean values ​​of each component value of the compensated point and the corresponding channel of the reference area to the mean values ​​of each component value of the reference area is calculated as the compensation value.

[0056] Step S140: for each pixel, the component values ​​of the corresponding channels are compensated according to the compensation values ​​of multiple channels.

[0057] In this step, the compensation unit 151 in the driving module 15 superimposes the compensation data (i.e., the compensation values ​​of multiple channels) with the grayscale data of the preset grayscale value (i.e., the multiple channel component values ​​of each pixel point in the pure grayscale image before compensation), thereby completing the compensation of the corresponding channel component values ​​and obtaining the compensated grayscale data (i.e., the multiple channel component values ​​of each pixel point after compensation).

[0058] Step S150: Determine whether the expected effect is achieved:

[0059] In this step, the driving module 15 drives the display panel 14 to display the compensated image according to the compensated grayscale data to confirm the compensation effect. If the expected effect is not achieved, steps S110 to S140 are repeated until the expected effect is achieved.

[0060] Step S160: storing the compensation values ​​of the multiple channels of each pixel point:

[0061] In this step, when the display image of the display panel 14 achieves the expected effect after compensation, the computer 11 stores the compensation values ​​of multiple channels of each pixel point in the flash memory 12 (Flash IC) as compensation data for color deviation compensation in the display stage.

[0062] The compensation data acquisition method of the present invention can realize RGB three-color compensation by only taking pictures of pure grayscale images under different grayscale values, avoiding the color cast caused by the display panel process when only the white screen is compensated in monochrome, and improving the reliability of compensation; at the same time, compared with the RGB three-color compensation of the prior art, the compensation method of the present invention can reduce the requirements for the camera, while reducing the production line photography time and improving the production capacity. Furthermore, according to the compensation method of the present invention, the compensation effect can also be confirmed by repeated multiple times, so that the compensation effect is optimized.

[0063] Furthermore, in some embodiments, the compensation data acquisition method of the present invention further includes step S170 and step S180:

[0064] S170, select the minimum number of repetitions:

[0065] In this step, when the expected effect is achieved, the minimum number of cycles of steps S110 to S140 is recorded as the minimum number of repetitions. For example, in some embodiments, the pure grayscale image displayed by the display panel before compensation is compared with that after the Nth compensation. If the difference in display effect of the display panel before compensation and that after the Nth compensation is lower than the set requirement, N is taken as the minimum number of repetitions, where N is a positive integer greater than or equal to 1; in some other embodiments, the pure grayscale image displayed by the display panel after the Mth compensation is compared with that after the M+1th compensation. If the difference in display effect of the display panel after the Mth compensation and that after the M+1th compensation is lower than the set requirement, M is taken as the minimum number of repetitions, where M is a positive integer greater than or equal to 1.

[0066] S180, verify the minimum number of repetitions:

[0067] In this step, the compensation data under the minimum number of repetitions is verified through multiple display panels, that is, the multiple display panels are compensated for the minimum number of repetitions to determine whether each display panel can achieve the expected effect under the minimum number of repetitions, and when the number of display panels that fail to achieve the expected effect exceeds a certain number (for example, in some embodiments, more than one display panel fails to achieve the expected effect), the minimum number of repetitions is reselected.

[0068] By confirming the minimum number of repetitions, repeated compensation due to defects in a certain display panel can be avoided, thereby further reducing the operation time.

[0069] According to the embodiments of the present invention as described above, these embodiments do not describe all the details in detail, nor do they limit the invention to the specific embodiments described. Obviously, many modifications and changes can be made based on the above description. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can make good use of the present invention and the modified use based on the present invention. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A method for compensating color deviation of a display panel, comprising a plurality of steps: Acquiring a pure grayscale image displayed by the display panel based on a preset grayscale value; Obtain component values ​​of multiple channels of each pixel in the RGB color system according to the pure grayscale image; Obtain compensation values ​​of the multiple channels of each pixel in the pure grayscale image according to the difference between the component value of each pixel in each channel in the RGB color system and the mean value of the corresponding channel component value of each pixel in the reference area in the pure grayscale image; as well as For each pixel point, the component values ​​of the corresponding channels are compensated respectively according to the compensation values ​​of the multiple channels. in, The method for obtaining component values ​​of multiple channels of each pixel in the RGB color system according to the pure grayscale image includes: Obtaining chromaticity information and brightness information of each pixel point according to the pure grayscale image data; Calculating the component values ​​of the X, Y, and Z channels of each pixel in the XYZ color system according to the chromaticity information and the brightness information; and Calculate the R, G, and B channel component values ​​of each pixel in the RGB color system according to the component values ​​of the X, Y, and Z channels, The color deviation compensation method also includes: if the display image of the display panel does not achieve the expected effect after compensation, repeatedly executing the multiple steps until the display image of the display panel achieves the expected effect; if the display image of the display panel achieves the expected effect after compensation, storing the compensation values ​​of the multiple channels of each pixel point for compensating for the color deviation in the display stage.

2. The color cast compensation method according to claim 1, wherein: The color cast compensation method further includes: Selecting a minimum number of repetitions; and Compensating the minimum number of repetitions for the plurality of display panels, and reselecting the minimum number of repetitions when the number of display panels that fail to achieve the expected effect exceeds the expected number, By performing the multiple steps a minimum number of times, the display image of the display panel after compensation can achieve the expected effect, thereby reducing the compensation time.

3. The color cast compensation method according to claim 2, wherein: The selecting of the minimum number of repetitions comprises: Compare the pure grayscale image displayed by the display panel before compensation and after the Nth compensation. If the difference in display effect of the display panel before compensation and after the Nth compensation is lower than the set requirement, N is used as the minimum number of repetitions, where N is a positive integer greater than or equal to 1.

4. The color cast compensation method according to claim 3, wherein: The selecting of the minimum number of repetitions comprises: Compare the pure grayscale image displayed by the display panel after the Mth compensation and the M+1th compensation. If the difference in display effect of the display panel after the Mth compensation and the M+1th compensation is lower than the set requirement, M is used as the minimum number of repetitions, where M is a positive integer greater than or equal to 1.

5. The color cast compensation method according to claim 3, wherein: The expected number is one.

6. The color cast compensation method according to claim 1, wherein: The reference area is the central area of ​​the pure grayscale image.

7. The color cast compensation method according to claim 1, wherein: The preset grayscale value is 2-4 different grayscale values.

8. The color cast compensation method according to claim 1, wherein: The display panel is one of LCD, OLED, and MicroLED.

9. A color deviation compensation system for a display panel, comprising: The display panel is used to display a pure grayscale image at a preset grayscale value according to the driving data; A driving module, connected to the display panel, and configured to provide the driving data to the display panel; An acquisition device, used for acquiring the pure grayscale image displayed by the display panel; A computer connected to the acquisition device, and used for calculating compensation values ​​of the multiple channels of each pixel in the pure grayscale image as compensation data according to the pure grayscale image; as well as A flash memory connected to the computer and the driving module, used for storing the compensation values ​​of the multiple channels and providing them to the driving module, Wherein, the color deviation compensation system compensates for the color deviation according to the color deviation compensation method according to any one of claims 1 to 8.

10. The color shift compensation system according to claim 9, wherein: The driving module further includes a compensation unit, and the driving module is configured as follows: providing the driving data to the display panel according to the grayscale data of the preset grayscale value, so that the display panel displays the pure grayscale image before compensation; as well as providing driving data to the display panel according to the compensated grayscale data so that the display panel displays the compensated grayscale image, The compensation unit is used for superimposing the compensation data and the grayscale data of the preset grayscale value to obtain the compensated grayscale data.

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