Display panel brightness adjustment method and device

Abstract

The present invention discloses a method and apparatus for adjusting brightness of a display panel, the method includes the steps of: obtaining brightness data of a plurality of pixels in a display panel; obtaining compensation data of a plurality of pixels according to the brightness data of the plurality of pixels, a preset target brightness data, and an aging curve of the pixels in the display panel; and using the compensation data to drive the plurality of pixels and perform an aging process on the plurality of pixels to adjust the brightness of the display panel to the target brightness. The present invention can make the brightness of the display panel uniform without adding additional DIC circuits and external memory, and improve the display uniformity of the display panel.

Description

[Technical Field]

[0001] This application claims priority to a Chinese patent application bearing application number 202110966799.X and entitled "Method and Apparatus for Adjusting Brightness of Display Panel," filed on August 23, 2021, and the specification, claims, accompanying drawings, and abstract of the above-mentioned Chinese patent application are incorporated herein by reference in their entirety.

[0002] The present invention relates to the field of display technology, and in particular to a method and apparatus for adjusting brightness of a display panel. [Background technology]

[0003] Both LED (Light-Emitting Diode) display technology and OLED (Organic Light-Emitting Diode) display technology have attracted much attention in the field of flat panel information displays. Both technologies have the advantages of self-illumination, high brightness, high contrast ratio, wide viewing angle, wide operating temperature range, and high reliability.

[0004] Both LED and OLED displays include corresponding display panels. Due to differences in manufacturing materials and / or manufacturing process errors, some display panels may exhibit the Mura phenomenon. Mura refers to the phenomenon of various traces (such as bright or dark spots) that occur due to uneven subpixel brightness on the display panel, causing visual discomfort and seriously affecting the quality of LCD panels. De-mura technology has been widely used to improve Mura defects. De-mura technology improves the display uniformity of display panels by changing the gray scale of the display screen according to the brightness and chromaticity shift conditions in various areas of the display panel. Currently, commonly used forms of de-mura include internal compensation and external compensation.

[0005] Internal compensation stores the TFT's threshold voltage (Vth) in the gate-source voltage (Vgs) during the compensation stage, and converts Vgs-Vth into current when light is emitted. Because Vgs already includes Vth, the conversion offsets the effect of Vth, achieving current consistency. However, the compensation effect of internal compensation is limited to the threshold voltage shift (Vth shift) of the drive circuit and the power supply voltage drop (IR drop), so the compensation effect is limited.

[0006] External compensation involves detecting the electrical or optical characteristics of pixels through an external driving circuit or device and performing compensation. This is exemplified by LG's mass-produced OLED display devices. External compensation can be divided into optical compensation and electrical compensation depending on the type of data detected. The optical method involves lighting the rear panel and then capturing images using an optical charge-coupled device (CCD) to read the brightness signal. The electrical method involves reading the electrical signals of the TFT and OLED through a sensing circuit. The electrical method is similar to internal compensation; it only measures the current difference and has limited compensation effectiveness. In contrast, the optical method has the best compensation effect and is the most widely used. However, the optical method requires additional DIC circuitry (Display Integrated Circuit, which is primarily used to input compensation data into the display and affect the circuitry, as well as to operate memories such as flash and SRAM) and a large amount of memory space (external flash, internal SRAM, etc.).

[0007] Therefore, there is a need to provide an improved technical solution to overcome the above technical problems in the prior art. Summary of the Invention

[0008] To solve the above technical problems, the present invention provides a method and apparatus for adjusting the brightness of a display panel. By using the collected pixel aging curves of the display panel and converting the non-uniform brightness data acquired by a brightness acquisition device (such as a camera) into the brightness data acquired by turning on the panel at a high temperature, the brightness of the display panel can be made uniform without adding an additional DIC circuit or external memory, thereby improving the display uniformity of the display panel.

[0009] According to a first aspect of the present disclosure, there is provided a method for adjusting brightness of a display panel, comprising: obtaining luminance data for a plurality of pixels in a display panel; Obtaining compensation data for the plurality of pixels according to the luminance data of the plurality of pixels, the target luminance data of the plurality of pixels, and an aging curve of pixels in the display panel; and driving the plurality of pixels using the compensation data to perform an aging process on the plurality of pixels to adjust the luminance of the display panel to a target luminance.

[0010] Optionally, the step of obtaining luminance data for a plurality of pixels in the display panel comprises: controlling the display panel to display a test image; and acquiring brightness data of a plurality of pixels in the display panel using a brightness acquisition device.

[0011] Optionally, obtaining compensation data for the plurality of pixels based on luminance data of the plurality of pixels, target luminance data of the plurality of pixels, and an aging curve of pixels in the display panel includes: obtaining the target luminance data based on luminance data of the plurality of pixels; Obtaining a pre-collected aging curve of a pixel in the display panel; calculating a difference between the acquired luminance data of each pixel in the plurality of pixels and the target luminance data; and obtaining compensation data for each pixel in the plurality of pixels based on the difference and the aging curve.

[0012] Optionally, the aging curve is a functional relationship or look-up table between the luminance difference and the illuminated gray scale when aging a pixel to a target luminance under conditions of a first temperature and a first time.

[0013] Optionally, the step of obtaining the target luminance data based on the luminance data of the plurality of pixels comprises: obtaining a target luminance data set based on a minimum luminance data of the luminance data of the plurality of pixels and a preset error tolerance range; selecting an arbitrary value of the target luminance data set as the target luminance data.

[0014] Optionally, the step of driving the plurality of pixels using the compensation data and performing an aging process on the plurality of pixels comprises: providing compensation data for the plurality of pixels corresponding to a plurality of pixels in the display panel; and controlling the display panel to drive the display panel at a first temperature for a first time based on the compensation data.

[0015] According to a second aspect of the present disclosure, there is provided a brightness adjustment device for a display panel, comprising: a luminance acquisition unit for acquiring luminance data of a plurality of pixels in the display panel; a generating unit for obtaining compensation data for a plurality of pixels according to the luminance data of the plurality of pixels, the target luminance data of the plurality of pixels, and an aging curve of pixels in the display panel; and an aging processing unit for providing an aging processing environment at a first temperature and a first time, wherein the display panel can drive the compensation data under the aging processing environment to achieve brightness adjustment.

[0016] Optionally, the brightness adjustment device The display device further includes a target brightness data acquiring unit for outputting target brightness data according to the brightness data of the plurality of pixels acquired by the brightness acquiring unit and a preset error tolerance range.

[0017] Optionally, the brightness adjustment device It further includes a memory for storing pre-collected aging curves of pixels in the display panel.

[0018] Optionally, the aging curve is a functional relationship or look-up table between the luminance difference and the illuminated gray scale when aging a pixel to a target luminance under conditions of a first temperature and a first time.

[0019] Optionally, the display panel comprises a cathode ray tube display panel, a digital light processing display panel, a liquid crystal display panel, a light emitting diode display panel, an organic light emitting diode display panel, a quantum dot display panel, a Micro-LED display panel, a Mini-LED display panel, a field emission display panel, a plasma display panel, an electrophoretic display panel or an electrowetting display panel.

[0020] The beneficial effects of the present invention are as follows: The present invention discloses a method and apparatus for adjusting the brightness of a display panel, which uses a brightness acquisition device (such as a camera) to acquire brightness data of multiple pixels on a display panel, and uses pre-collected aging curves of the pixels on the display panel to acquire the gray scale required for lighting, i.e., compensation data, to adjust the brightness of each pixel to a target brightness, and ages the display panel by lighting it at a high temperature, aging overly bright pixel points on the panel to the target brightness, thereby making the brightness of the display panel uniform without adding an additional DIC circuit or external memory, and thereby improving the display uniformity of the display panel.

[0021] It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention. [Brief explanation of the drawings]

[0022] [Figure 1] FIG. 1 shows a flowchart of a brightness adjustment method for a display panel provided by an embodiment of the present disclosure. [Figure 2] FIG. 2 shows a flowchart of a method for obtaining luminance data of multiple pixels in a display panel provided by an embodiment of the present disclosure. [Figure 3] FIG. 3 shows a flowchart of a method for obtaining compensation data for multiple pixels provided by an embodiment of the present disclosure. [Figure 4a] FIG. 4a shows a schematic diagram of the luminance distribution of a display panel at G160 gray scale provided by an embodiment of the present disclosure. [Figure 4b] FIG. 4b shows a schematic diagram of the aging curve provided by an embodiment of the present disclosure. [Figure 4c] FIG. 4c shows a schematic diagram of the luminance distribution when driving the compensation data through the display panel provided by an embodiment of the present disclosure. [Figure 4d]FIG. 4d shows a schematic diagram of the luminance distribution of the display panel at G160 gray scale after aging treatment provided by an embodiment of the present disclosure. [Figure 5] FIG. 5 shows a schematic structural diagram of a brightness adjusting device for a display panel provided by an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0023] To facilitate understanding of the present invention, the present invention will now be described in more detail with reference to the accompanying drawings. Preferred embodiments of the present invention are illustrated in the accompanying drawings. However, the present invention may be embodied in different forms and is not limited to the embodiments set forth herein. Rather, these embodiments are provided to provide a more complete and comprehensive understanding of the present disclosure.

[0024] The present invention will now be described in detail with reference to the accompanying drawings.

[0025] FIG. 1 shows a flowchart of a brightness adjustment method for a display panel provided by an embodiment of the present disclosure.

[0026] As shown in FIG. 1, in the present disclosure, the brightness adjusting method for a display panel includes performing steps S1 to S3.

[0027] Specifically, in step S1, brightness data of a plurality of pixels on a display panel is obtained.

[0028] Referring to FIG. 2, the method for acquiring brightness data of a plurality of pixels in a display panel includes controlling the display panel to display a test image (step S11), and using a brightness acquisition device to acquire brightness data of a plurality of pixels in the display panel (step S12).

[0029] In this embodiment, when controlling the display panel to display a test image, any grayscale value can be selected within the grayscale range of G0 to G255 to light up multiple pixels on the display panel. Illustratively, the test image displayed by the display panel is configured with driving data corresponding to a single grayscale value, so that the brightness difference of multiple pixels on the display panel (corresponding to all pixels on the display panel, and each pixel corresponding to one light-emitting element) can be better distinguished.

[0030] Optionally, the plurality of pixels in the display panel correspond to some or all of the pixels in the display panel, and each pixel corresponds to one light-emitting device in the display panel. Illustratively, the display panel in the present disclosure may be a cathode ray tube display panel, a digital light processing display panel, a liquid crystal display panel, a light-emitting diode display panel, an organic light-emitting diode display panel, a quantum dot display panel, a Micro-LED display panel, a Mini-LED display panel, a field emission display panel, a plasma display panel, an electrophoretic display panel, or an electrowetting display panel.

[0031] Furthermore, if the brightness acquisition device is a CCD camera, when acquiring brightness data of multiple pixels on the display panel, the CCD camera can be used to capture a test image displayed on the display panel, and referring to Figure 4a (taking the grayscale of G160 as an example), the brightness distribution data of the display panel at the current grayscale can be acquired.

[0032] In step S2, compensation data for a plurality of pixels is obtained according to the luminance data of a plurality of pixels, the target luminance data of a plurality of pixels, and the aging curve of the pixels in the display panel.

[0033] Referring to FIG. 3, step S2 may further include: obtaining target brightness data based on brightness data of a plurality of pixels (step S21); obtaining a pre-collected aging curve of pixels in the display panel (step S22); calculating a difference between the brightness data of each pixel in the plurality of pixels and the target brightness data (step S23); and obtaining compensation data for each pixel in the plurality of pixels based on the difference and the aging curve (step S24).

[0034] In this embodiment, the step of acquiring target brightness data based on the brightness data of the plurality of pixels includes acquiring a target brightness data set based on the minimum brightness data among the brightness data of the plurality of pixels and a preset error tolerance, and selecting an arbitrary value of the target brightness data set as the target brightness data. For example, if the minimum brightness data among the brightness data of the plurality of pixels acquired by the brightness acquisition device is 100 and the preset error tolerance is ±10%, the acquired target brightness data set is 100*90% to 100*110%, i.e., 90 to 110. In this case, one value from the range of 90 to 110 can be selected as the target brightness data. In this way, it is possible to ensure that the brightness of all pixels can be adjusted to a consistent brightness during the subsequent aging process of the display panel. Of course, in other embodiments of the present invention, other methods can be used to obtain the target pixel luminance, for example, selecting luminance data of a plurality of pixels ranked in 1 / 4 order from smallest to largest as the target luminance data, or selecting the average value of the luminance data of some of the smallest pixels as the target luminance data, etc. The above numerical values ​​in the present invention are merely examples, and can be selected according to actual conditions, and it can be understood that the present invention is not limited thereto.

[0035] Furthermore, if the difference between the minimum brightness data and other brightness data among the brightness data of multiple pixels is too large, the pixel corresponding to the brightness data is checked, thereby preventing pixel damage from affecting the brightness adjustment results of the display panel, and improving the accuracy of the brightness adjustment results.

[0036] In this embodiment, as shown in Figure 4b, the pre-collected aging curve of a pixel in a display panel is a functional relationship equation or look-up table between the luminance difference and the lit grayscale when the pixel is aged to the target luminance under the conditions of a first temperature (e.g., 120°C) and a first time (e.g., 1 hour), which is used to characterize the correspondence relationship between the difference between the luminance data of a pixel in a display panel and the target luminance data and the compensated grayscale value. That is, when the difference between the luminance data and the target luminance data of a specific pixel is obtained, the grayscale value that needs to be loaded into the pixel in the subsequent aging process can be estimated based on the aging curve, i.e., the compensation data corresponding to the pixel is obtained.

[0037] In this embodiment, the aging curve is prior information and can be obtained through measurement. For example, when collecting the aging curve of a pixel in a display panel to be measured, all gray scales G0 to G255 can be sequentially applied to pixels (light-emitting devices) with the same specifications as the pixel in the display panel to be measured. After aging at a first temperature (e.g., 120°C) for a first time (e.g., 1 hour), the luminance degradation values ​​of each gray scale G0 to G255 can be sequentially collected, and finally, the aging curve can be organized and formed. Furthermore, the aging curve can be stored in memory for easy subsequent retrieval.

[0038] In step S3, the compensation data is used to drive the plurality of pixels, and an aging process is performed on the plurality of pixels, so as to adjust the luminance of the display panel to the target luminance.

[0039] In this embodiment, step S3 further includes providing compensation data for a plurality of pixels corresponding to a plurality of pixels in a display panel, and controlling the display panel to drive at a first temperature and for a first time based on the compensation data.

[0040] After obtaining the compensation data for the plurality of pixels, the compensation data for the plurality of pixels can be written into the storage unit. The aging treatment for the plurality of pixels in the display panel involves placing the display panel in an environment of a first temperature (e.g., 120°C) and turning on the power, reading the compensation data for the plurality of pixels in the storage unit, and driving corresponding pixels in the display panel respectively for a first time (e.g., 1 hour) based on the compensation data, and aging the overly bright pixels in the display panel to a target brightness using the principle that pixel brightness decreases when operating at high temperatures.

[0041] Referring to Figures 4c and 4d, Figure 4c shows a schematic diagram of the luminance distribution of a display panel when compensation data is driven immediately after power-on. In the displayed image, the luminance data of multiple pixels are all higher than the target luminance data. Figure 4d shows a schematic diagram of the luminance distribution of the display panel when the display panel is aged at a first temperature (e.g., 120°C) for a first time (e.g., 1 hour) and then driven again with the G160 gray scale. In the displayed image, the luminance data of multiple pixels tends to be uniform. Furthermore, the present invention adjusts the luminance of the display panel by aging the panel at a high temperature, thereby uniforming the luminance of the display panel and improving the display uniformity of the display panel without adding an additional DIC circuit or external memory.

[0042] The aging treatment conditions set in this disclosure (including the aging treatment conditions when collecting the aging curve and the aging treatment conditions when performing the aging treatment on the display panel after obtaining the compensation data, and both aging treatment conditions should be the same) are 120°C for 1 hour, but this condition is just an example, and the actual aging treatment conditions may be any conditions and should be reasonably selected according to the actual situation. For example, in order to shorten the manufacturing time, the aging treatment conditions may be set to 200°C for 10 minutes, and the present invention is not limited thereto.

[0043] Furthermore, in the process of collecting the aging curve and adjusting the brightness of the display panel, the present invention ensures the accuracy and reliability of the brightness data of multiple pixels on the display panel acquired by the brightness acquisition device, since the brightness of the ambient light in the test environment is the same, which helps to improve the accuracy of the brightness adjustment results of the display panel.

[0044] Optionally, after the aging process of a plurality of pixels in the display panel is completed, step S1 is performed again to verify the brightness adjustment result of the display panel and ensure that the adjustment result can meet the requirements.

[0045] Furthermore, the present invention further discloses a brightness adjusting device for a display panel, which includes a brightness obtaining unit 100, a generating unit 200 and an aging processing unit 300, as shown in FIG.

[0046] A luminance acquisition unit (i.e., the aforementioned luminance acquisition device such as a CCD camera) 100 is used to collect luminance data of multiple pixels in a display panel. A generation unit 200 is connected to the luminance acquisition unit 100 and is used to acquire compensation data for multiple pixels according to the luminance data of the multiple pixels, target luminance data of the multiple pixels, and an aging curve of the pixels in the display panel. An aging processing unit 300 is connected to the generation unit 200 and provides an aging processing environment at a first temperature and a first time, so that the display panel can drive the compensation data under the aging processing environment to achieve luminance adjustment.

[0047] Furthermore, the brightness adjusting device for a display panel further includes a target brightness data acquiring unit 400, which is connected to the brightness acquiring unit 100 and the generating unit 200, and outputs target brightness data according to the brightness data of the plurality of pixels acquired by the brightness acquiring unit 100 and a preset error tolerance range.

[0048] Furthermore, the brightness adjusting device for a display panel further includes a memory 500. The memory 500 stores a previously collected aging curve of a pixel in the display panel. The aging curve stored in the memory 500 is a functional relationship or look-up table between a luminance difference and a lighting gray scale when a pixel in the display panel is aged to a target luminance under conditions of a first temperature and a first time.

[0049] It should be understood that the brightness adjusting device for a display panel disclosed in the present invention can be used to implement the brightness adjusting method for a display panel as shown in Figures 1 to 4d. Therefore, for the specific operating principles of each component unit in the brightness adjusting device for a display panel shown in this embodiment, reference can be made to the above description of the brightness adjusting method for a display panel, and they will not be repeated here.

[0050] Furthermore, the technical solution disclosed by the present invention can age excessively bright pixel points in a display panel to a target brightness, and has a wide range of applications. For example, it can be applied to any display product. That is, the display panel in this embodiment may include a cathode ray tube display panel, a digital light processing display panel, a liquid crystal display panel, a light emitting diode display panel, an organic light emitting diode display panel, a quantum dot display panel, a micro-LED display panel, a Mini-LED display panel, a field emission display panel, a plasma display panel, an electrophoretic display panel, or an electrowetting display panel.

[0051] As described above, the present invention obtains brightness data of multiple pixels in a display panel, and uses a pre-collected aging curve to obtain the gray scale required for lighting to adjust the brightness of each pixel to a target brightness. When the panel is aged at a high temperature, excessively bright pixel points in the panel can be aged to the target brightness, and the brightness of the display panel can be made uniform without adding an additional DIC circuit or external memory, thereby improving the display uniformity of the display panel. At the same time, the technical solution of the present invention is applicable to all display products and has a wide range of applications.

[0052] It should be noted that the above examples are merely examples for clearly explaining the examples of the present invention, rather than limiting the embodiments. Those skilled in the art can make other modifications or variations in different forms based on the above description. It is not necessary and impossible to cover all the embodiments here. However, obvious modifications or variations derived therefrom still fall within the scope of protection of the present invention.

Claims

1. obtaining luminance data for a plurality of pixels in a display panel; Obtaining compensation data for the plurality of pixels according to the luminance data of the plurality of pixels, the target luminance data of the plurality of pixels, and an aging curve of pixels in the display panel; and driving the plurality of pixels using the compensation data to perform an aging process on the plurality of pixels to adjust the luminance of the display panel to a target luminance; the aging curve is a functional relationship or look-up table between a luminance difference and a gray scale illuminated when aging a pixel to a target luminance under conditions of a first temperature and a first time; The compensation data represents a grayscale value corresponding to the brightness difference based on the aging curve, and the compensation data is used to drive a corresponding pixel that undergoes the aging treatment lasting for the first time at the first temperature.

2. The step of obtaining luminance data of a plurality of pixels in the display panel includes: controlling the display panel to display a test image; and acquiring brightness data of a plurality of pixels in the display panel using a brightness acquisition device.

3. Obtaining compensation data for the plurality of pixels according to brightness data of the plurality of pixels, target brightness data of the plurality of pixels, and an aging curve of pixels in the display panel includes: obtaining the target luminance data based on luminance data of the plurality of pixels; obtaining a pre-collected aging curve of a pixel in the display panel; calculating a difference between luminance data of each pixel in the plurality of pixels and the target luminance data; and obtaining compensation data for each pixel in the plurality of pixels based on the difference and the aging curve.

4. The step of obtaining the target luminance data based on the luminance data of the plurality of pixels includes: obtaining a target luminance data set based on a minimum luminance data of the luminance data of the plurality of pixels and a preset error tolerance range; and selecting an arbitrary value of the target brightness data set as the target brightness data.

5. driving the plurality of pixels using the compensation data and performing an aging process on the plurality of pixels, providing compensation data for the plurality of pixels corresponding to a plurality of pixels in the display panel; and controlling the display panel to drive under the first temperature and for the first time period based on the compensation data.

6. a luminance acquisition unit for acquiring luminance data of a plurality of pixels in a display panel; a generating unit for obtaining compensation data for a plurality of pixels according to the luminance data of the plurality of pixels, the target luminance data of the plurality of pixels, and an aging curve of pixels in the display panel; an aging processing unit for providing an aging processing environment at a first temperature and a first time, wherein the display panel can drive the compensation data under the aging processing environment to achieve brightness adjustment; the aging curve is a functional relationship or look-up table between a luminance difference and a gray scale illuminated when aging a pixel to a target luminance under the conditions of the first temperature and the first time; A brightness adjustment device, wherein the compensation data represents a grayscale value corresponding to the brightness difference based on the aging curve, and the compensation data is used to drive a corresponding pixel that undergoes aging processing by the aging processing unit under the aging processing environment.

7. The brightness adjustment device 7. The brightness adjusting device according to claim 6, further comprising a target brightness data acquiring unit for outputting the target brightness data based on the brightness data of the plurality of pixels acquired by the brightness acquiring unit and a preset error tolerance range.

8. The brightness adjustment device The brightness adjusting device according to claim 6 , further comprising a memory for storing pre-collected aging curves of pixels in the display panel.

9. The brightness adjusting device according to any one of claims 6 to 8, wherein the display panel comprises a cathode ray tube display panel, a digital light processing display panel, a liquid crystal display panel, a light emitting diode display panel, an organic light emitting diode display panel, a quantum dot display panel, a Mirco-LED display panel, a Mini-LED display panel, a field emission display panel, a plasma display panel, an electrophoretic display panel, or an electrowetting display panel.

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