Picture compensation method and display device

Abstract

The invention provides a picture compensation method and a display device, belongs to the technical field of brightness compensation, aims to improve the accuracy of brightness compensation and is applied to the display device, the display device comprises a plurality of pixels, each pixel comprises a pixel driving circuit, and the method comprises the following steps: selecting a pixel driving circuit from picture data to be displayed, obtaining an input gray scale corresponding to each pixel and a display parameter of the display device; determining a first compensation value corresponding to the input gray scale of each pixel based on the accumulated display duration, the input gray scale of each pixel and a preset brightness attenuation relationship; determining a second compensation value corresponding to the input gray scale of each pixel based on the accumulated display duration, the input gray scale corresponding to each pixel and a preset current attenuation relationship; wherein the current attenuation relation is used for representing the relation between the current of the pixel driving circuit and the accumulated display duration under different gray scales; and compensating the input gray scale corresponding to each pixel based on the first compensation value and the second compensation value.

Description

Technical Field

[0001] This disclosure relates to the field of brightness compensation technology, and in particular to a screen compensation method and display device. Background Technology

[0002] In the development of OLED display technology, brightness compensation design is a key step in improving display quality. However, the accuracy of brightness compensation in current display devices is insufficient. Summary of the Invention

[0003] Based on the background technology, this disclosure proposes a screen compensation method and a display device.

[0004] In a first aspect, this disclosure provides a screen compensation method applied to a display device, the display device including a plurality of pixels, each pixel including a pixel driving circuit, the method comprising: From the image data to be displayed, obtain the input grayscale corresponding to each pixel and the display parameters of the display device, wherein the display parameters include the cumulative display duration of the display device; Based on the cumulative display duration, the input grayscale of each pixel, and the preset brightness attenuation relationship, a first compensation value corresponding to the input grayscale of each pixel is determined; wherein, the brightness attenuation relationship is used to characterize the relationship between the display brightness of the pixel and the cumulative display duration under different grayscale levels; Based on the cumulative display duration, the input grayscale corresponding to each pixel, and the preset current attenuation relationship, a second compensation value corresponding to the input grayscale of each pixel is determined; wherein, the current attenuation relationship is used to characterize the relationship between the current of the pixel driving circuit and the cumulative display duration under different grayscale levels; Based on the first compensation value and the second compensation value, the input grayscale corresponding to each pixel is compensated.

[0005] Optionally, determining the first compensation value corresponding to the input grayscale of each pixel based on the cumulative display duration, the input grayscale of each pixel, and a preset brightness attenuation relationship includes: Obtain a first compensation table, which is obtained by fitting the brightness attenuation relationship; wherein, the first compensation table includes compensation values ​​corresponding to different cumulative display durations and different input gray levels; Find the first compensation value corresponding to the cumulative display duration and the input grayscale from the first compensation table.

[0006] Optionally, determining the second compensation value corresponding to the input grayscale of each pixel based on the cumulative display duration, the input grayscale corresponding to each pixel, and a preset current attenuation relationship includes: Obtain a second compensation table, which is obtained by fitting the current attenuation relationship; wherein, the second compensation table includes compensation values ​​corresponding to different cumulative display durations and different input gray levels; Find the second compensation value corresponding to the cumulative display duration and the input grayscale from the second compensation table.

[0007] Optionally, the current decay relationship is determined through the following steps: The display device is driven to display a test screen, which includes multiple image blocks; Multiple image blocks are lit up respectively, and when each image block is lit up, the current value of the image block under different gray levels and different cumulative display durations is detected; Based on the current values ​​corresponding to the multiple gray levels and the multiple cumulative display durations, the change of the current value with respect to the gray levels and the cumulative display duration is determined; The current attenuation relationship is determined based on the change of the current value with the grayscale and the cumulative display duration.

[0008] Optionally, lighting up the plurality of image blocks respectively includes: Multiple image blocks are illuminated in several stages, with different image blocks illuminated each time. When the image block is lit up, among the multiple image blocks, the image blocks other than the lit image block are displayed as black.

[0009] Optionally, the method for obtaining the brightness attenuation relationship includes: The test screen is displayed using the aforementioned display device, and the test screen includes multiple image blocks; wherein the display colors of the multiple image blocks are not exactly the same; Obtain the brightness values ​​of the display device at different gray levels and different cumulative display durations; Based on the brightness values ​​corresponding to the multiple gray levels and the multiple cumulative display durations, the change of the brightness value with respect to the gray levels and the cumulative display duration is determined; The brightness attenuation relationship is determined based on the change of the brightness value with the grayscale and the cumulative display duration.

[0010] Optionally, in every 2×2 image blocks in the test screen, the two image blocks located on the first diagonal are both black image blocks, and the two image blocks located on the second diagonal are different in color from each other and are different from the black image blocks; The first diagonal and the second diagonal are two intersecting diagonals in a 2×2 image block.

[0011] Optionally, the display parameters may also include the current temperature of the display device; The step of determining the second compensation value corresponding to the input grayscale of each pixel based on the cumulative display duration, the input grayscale corresponding to each pixel, and a preset current attenuation relationship includes: Based on the cumulative display duration, the input grayscale corresponding to each pixel, the current temperature, and the current attenuation relationship, a second compensation value is determined for each pixel.

[0012] Optionally, the step of compensating the input grayscale corresponding to each pixel based on the first compensation value and the second compensation value includes: Obtain the weights corresponding to the first compensation value and the second compensation value, respectively; The input grayscale corresponding to each pixel is compensated using the first compensation value, the second compensation value, and their respective weights.

[0013] A second aspect of this disclosure provides a display device, including a display panel and a display driving module; The driving display module is used to execute the image compensation method described in the first aspect above.

[0014] Optionally, it also includes a storage unit, which stores a first compensation table and a second compensation table; The driving display module is also used to look up the first compensation value corresponding to the cumulative display duration and input grayscale from the first compensation table; And a second compensation value used to look up the cumulative display duration and input grayscale from the second compensation table; The first compensation table is obtained by fitting the brightness attenuation relationship, and the second compensation table is obtained by fitting the current attenuation relationship.

[0015] The image compensation method disclosed herein is applied to a display device, which includes multiple pixels, each pixel including a pixel driving circuit. The method includes: obtaining, from image data to be displayed, an input grayscale corresponding to each pixel and display parameters of the display device, the display parameters including the cumulative display duration of the display device; determining a first compensation value corresponding to the input grayscale of each pixel based on the cumulative display duration, the input grayscale of each pixel, and a preset brightness attenuation relationship; wherein the brightness attenuation relationship is used to characterize the relationship between the display brightness of the pixel and the cumulative display duration at different grayscales; determining a second compensation value corresponding to the input grayscale of each pixel based on the cumulative display duration, the input grayscale corresponding to each pixel, and a preset current attenuation relationship; wherein the current attenuation relationship is used to characterize the relationship between the current of the pixel driving circuit and the cumulative display duration at different grayscales; and compensating for the input grayscale corresponding to each pixel based on the first compensation value and the second compensation value. Therefore, the image compensation method disclosed herein obtains the compensation value corresponding to the brightness attenuation of the pixel through a preset brightness attenuation relationship, display parameters, and input grayscale, and obtains the compensation value corresponding to the current attenuation of the pixel driving circuit through a preset current attenuation relationship, display parameters, and input grayscale. Then, the two compensation values ​​are used to comprehensively compensate the input grayscale of the pixel, thereby improving the compensation accuracy and further improving the display quality.

[0016] The above description is merely an overview of the technical solution disclosed herein. In order to better understand the technical means of this disclosure and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this disclosure more apparent and understandable, specific embodiments of this disclosure are described below. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments or related technologies of this disclosure, the accompanying drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. It should be noted that the scale in the drawings is for illustration only and does not represent the actual scale.

[0018] Figure 1 A flowchart illustrating the steps of the image compensation method provided in this embodiment is shown. Figure 2 A flowchart illustrating the steps of the method for obtaining the current attenuation relationship in an embodiment of this disclosure is shown; Figure 3 A flowchart illustrating the steps of the method for obtaining the brightness attenuation relationship in an embodiment of this disclosure is shown; Figure 4 A schematic diagram of a test screen in an embodiment of this disclosure is shown; Figure 5 A schematic diagram showing the test screen being lit up multiple times in an embodiment of this disclosure is shown; Figure 6 A schematic diagram of the structure of the display device provided in an embodiment of this disclosure is shown; Figure 7 A schematic flowchart of the image compensation method in an embodiment of this disclosure is shown. Detailed Implementation

[0019] To make the above-mentioned objectives, features, and advantages of this disclosure more apparent and understandable, the technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this disclosure. Based on the embodiments of this disclosure, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this disclosure.

[0020] In related technologies, brightness compensation design typically relies on parameters such as OLED brightness, emission time, and temperature to determine the degradation of the light-emitting material in the pixels, and then compensates for this degradation. However, research shows that after prolonged use, transistors in the pixel driving circuit of OLED displays also age, causing a decrease in driving current and consequently, a decrease in the brightness of the display. Therefore, current brightness compensation schemes, which only consider brightness degradation caused by the degradation of the pixel's light-emitting material, have limited accuracy.

[0021] In view of this, the present disclosure provides a screen compensation method and display device, which improves the compensation accuracy of brightness compensation by adding compensation for the current attenuation of the pixel driving circuit on the basis of the original brightness attenuation compensation.

[0022] Reference Figure 1 , Figure 1 A flowchart illustrating the steps of a screen compensation method provided in an embodiment of this disclosure is shown. This screen compensation method is applied to a display device, which includes a plurality of pixels, each pixel including a pixel driving circuit, such as... Figure 1 As shown, the image compensation method specifically includes: S101, obtain the input grayscale corresponding to each pixel and the display parameters of the display device from the screen data to be displayed. The display parameters include the cumulative display duration of the display device.

[0023] S102, based on the cumulative display duration, the input grayscale of each pixel, and the preset brightness attenuation relationship, determines the first compensation value corresponding to the input grayscale of each pixel.

[0024] Among them, the brightness decay relationship is used to characterize the relationship between the display brightness of a pixel and the cumulative display time at different gray levels.

[0025] S103 determines the second compensation value corresponding to the input gray level of each pixel based on the cumulative display duration, the input gray level corresponding to each pixel, and the preset current attenuation relationship.

[0026] Among them, the current decay relationship is used to characterize the relationship between the current of the pixel driving circuit and the cumulative display time under different gray levels.

[0027] In this embodiment, when displaying the screen, the image data to be displayed can be obtained so as to obtain the input grayscale corresponding to each pixel based on the image data; at the same time, the display parameters of the display device can be obtained. The display parameters may include the cumulative display duration of the display device, which represents the total display duration of the display device from the first display of the screen to the current time period, or the cumulative display duration may be the cumulative light emission duration of each pixel in the display device from the first light emission to the current time period.

[0028] In some examples, the temperature of the display device also affects the degree of decay of the light-emitting material of the pixels, as well as the current value of the pixel driving circuit. Therefore, the display parameters of the display device may also include the current temperature of the display device, so as to facilitate the subsequent acquisition of the brightness decay relationship and current decay relationship corresponding to the current temperature.

[0029] The preset brightness attenuation relationship and preset current attenuation relationship can be obtained and stored in the display device during the testing phase. Therefore, when the display device is in operation, the brightness attenuation relationship and current attenuation relationship can be directly obtained. The display brightness of a pixel decreases as the cumulative display time of the display device increases, and the degree of brightness attenuation varies at different gray levels. Similarly, the current of the pixel driving circuit decreases as the cumulative display time of the display device increases, and the degree of current attenuation varies at different gray levels. Therefore, when determining the compensation value, the input gray level corresponding to each pixel can be introduced. That is, based on the pixel's input gray level, cumulative display time, and preset brightness attenuation relationship, the compensation value corresponding to brightness attenuation is determined; and based on the pixel's input gray level, cumulative display time, and preset current attenuation relationship, the compensation value corresponding to current attenuation is determined.

[0030] Specifically, the process of determining the first compensation value can be as follows: first, determine the brightness attenuation value based on the cumulative display time and the input grayscale; then, determine the first compensation value corresponding to the brightness attenuation value. This first compensation value can be calculated based on the brightness attenuation value, or the compensation values ​​corresponding to different brightness attenuation values ​​can be stored in advance. After obtaining the brightness attenuation value, the first compensation value corresponding to the brightness attenuation value is determined. Similarly, the process of determining the second compensation value can be as follows: first, determine the current attenuation value based on the cumulative display time and the input grayscale; then, determine the second compensation value corresponding to the current attenuation value. This compensation value can be calculated based on the current attenuation value, or the compensation values ​​corresponding to different current attenuation values ​​can be stored in advance. After obtaining the current attenuation value, the second compensation value corresponding to the current attenuation value is determined.

[0031] It is understandable that the process of obtaining the first compensation value and the second compensation value does not distinguish the order of execution. That is, the execution order of steps S102 and S103 is not limited. Specifically, step S102 can be executed first and then step S103 can be executed, or step S103 can be executed first and then step S102 can be executed, or steps S102 and S103 can be executed simultaneously.

[0032] S104, based on the first compensation value and the second compensation value, compensate for the input grayscale corresponding to each pixel.

[0033] After obtaining the first compensation value and the second compensation value, the first compensation value and the second compensation value can be directly used to compensate the input gray level corresponding to each pixel, and then the compensated gray level value can be used to drive the display to display the image.

[0034] In some examples, weights can be assigned to the first compensation value and the second compensation value respectively. Then, when compensating the input grayscale, the compensation can be performed by combining the weights corresponding to the first compensation value and the second compensation value respectively.

[0035] The image compensation method provided in this embodiment determines a first compensation value based on a preset brightness attenuation relationship, the grayscale value of each pixel, and the cumulative display duration when the display device is displaying an image. Simultaneously, a second compensation value is determined based on a preset current attenuation relationship, the grayscale value of each pixel, and the cumulative display duration. The first and second compensation values ​​are used to compensate the input grayscale of each pixel. Therefore, during image compensation, not only is the input grayscale of each pixel compensated based on the brightness attenuation of the pixel, but also on the current attenuation of the pixel driving current included in the pixel. This improves the compensation accuracy of image compensation for the display device and enhances display quality.

[0036] In one embodiment, compensation values ​​under different brightness attenuation and different current attenuation conditions can be directly obtained during the display device testing phase. Then, during image compensation, the corresponding compensation value can be determined directly based on the brightness attenuation and current attenuation conditions.

[0037] Specifically, for the first compensation value, a first compensation table can be obtained first, which is obtained by fitting the brightness attenuation relationship; wherein, the first compensation table includes compensation values ​​corresponding to different cumulative display durations and different input gray levels; then, the first compensation value corresponding to the cumulative display duration and input gray level is found from the first compensation table.

[0038] In this embodiment, the brightness compensation value corresponding to different brightness attenuation values ​​can be determined during the testing phase. Since different gray levels and different cumulative display durations correspond to different brightness attenuation values, the compensation values ​​corresponding to different gray levels and different cumulative display durations can be determined, thereby forming a first compensation table. When compensating the screen, the stored first compensation table can be directly obtained, and the corresponding first compensation value can be found from the first compensation table based on the cumulative display duration and the input gray level of the pixel.

[0039] For the second compensation value, the second compensation table can be obtained first. The second compensation table is obtained by fitting the current attenuation relationship. The second compensation table includes compensation values ​​corresponding to different cumulative display durations and different input gray levels. Then, the second compensation value corresponding to the cumulative display duration and input gray level can be found from the second compensation table.

[0040] Similarly, during the testing phase, the current compensation value corresponding to different current attenuation values ​​can be determined. Since different gray levels and different cumulative display durations correspond to different current attenuation values, the compensation values ​​corresponding to different gray levels and different cumulative display durations can be determined, thus forming a second compensation table. Subsequently, during image compensation, the stored second compensation table can be directly retrieved, and the corresponding second compensation value can be found from the second compensation table based on the cumulative display duration and the input gray level of the pixel. It should be noted that when the display device is displaying an image, even if some pixels are not emitting light, the pixel driving circuit still experiences current attenuation. Therefore, for brightness attenuation, the cumulative display duration can be the cumulative light-emitting duration of the pixel, while for current attenuation, the cumulative display duration can be the cumulative image display duration of the display device. That is, when obtaining the compensation value, the corresponding first compensation value is determined based on the cumulative light-emitting duration of the pixel and the input gray level, and the corresponding second compensation value is determined based on the cumulative image display duration of the display device and the input gray level.

[0041] In this disclosure, the preset brightness decay relationship and the preset current decay relationship can both be obtained by performing an aging test on the display device in advance. When performing an aging test on the display device, the current of the display device can be detected to obtain the current decay of the pixel driving circuit, and the display brightness of the display device can be detected to obtain the brightness decay of the pixels.

[0042] In one scenario, the current decay relationship is obtained during an aging test of the display device. In this case, reference is made to... Figure 2 , Figure 2 The method for obtaining the current attenuation relationship in an embodiment of this disclosure is shown, such as... Figure 2 As shown, the method specifically includes: S201, drive the display device to display the test screen, which includes multiple image blocks.

[0043] S202, illuminates multiple image blocks respectively, and when illuminating each image block, detects the current value of the image block under different gray levels and different cumulative display durations.

[0044] S203 determines the current attenuation relationship based on the change of current value with grayscale and cumulative display time.

[0045] In this embodiment, the display device is driven to display a test screen for aging test. During the aging test, multiple test time points are determined. Each time a test time point is reached, multiple image blocks are lit up. When an image block is lit up, the current value of the display device detected is the current value of that image block.

[0046] This method allows the same image block to be illuminated multiple times. Each time the image block is illuminated, its grayscale level differs, allowing for the testing of the current value at different grayscale levels. It's important to note that during the illumination of multiple image blocks, the multiple display grayscale levels of each image block remain the same to obtain the current attenuation in different areas of the display device. For example, when image block A is illuminated, its current value is measured at grayscale levels 32, 127, and 255. Similarly, when image block B is illuminated, its current value at grayscale levels 32, 127, and 255 should also be measured.

[0047] After determining the change of current value with grayscale and cumulative display time, a relationship curve can be fitted to determine the current decay relationship. This current decay relationship can include the relationship curves of current value change with cumulative display time under multiple grayscale levels.

[0048] In this test, all the image blocks in the test screen have the same area, so the size of the image block that is lit up each time is the same, in order to ensure the accuracy of the current value of the final display device. When the pixels can display different colors of light, the current value of the image block can also be detected when displaying different colors of light.

[0049] It is understandable that during the process of lighting up multiple image blocks, each image block is lit up independently so that when the current value corresponding to the image block is detected each time, it will not be affected by the interference of adjacent image blocks. Specifically, the process of lighting up multiple image blocks can be done by lighting up multiple image blocks in multiple sessions, with different image blocks lit up each time. When lighting up an image block, the image blocks other than the lit image blocks will display a black screen.

[0050] Understandably, the image blocks other than the lit ones will display a black screen. That is, except for the pixels in the area where the lit image blocks are located, the pixels in other areas of the display device will not be lit. This can avoid the situation where the current detection is inaccurate due to the lighting of other image blocks.

[0051] In another example, when performing an aging test on a display device to obtain the brightness decay relationship, reference is made to... Figure 3 , Figure 3 The method for obtaining the brightness attenuation relationship in an embodiment of this disclosure is shown, such as... Figure 3 As shown, the method specifically includes: S301, a display device is used to display a test screen, which includes multiple image blocks; wherein the display colors of the multiple image blocks are not exactly the same.

[0052] S302, acquire the brightness values ​​of the display device under different gray levels and different cumulative display durations.

[0053] S303 determines the brightness decay relationship based on the changes in brightness value with grayscale and cumulative display time.

[0054] In this embodiment, the brightness values ​​of multiple image blocks under the test screen can be obtained during the aging test phase. Since the display colors of the multiple image blocks are not exactly the same, the change of pixel brightness values ​​under different display colors with the cumulative display time can be obtained.

[0055] Specifically, during the aging test phase of the display device, the brightness value of the display device can be detected after continuously displaying the test screen for a period of time. Then, the grayscale of multiple test screens can be adjusted to obtain the brightness value of the display device under different grayscale levels. After that, the display device continues to undergo aging tests until the brightness values ​​under different cumulative durations and different grayscale levels are obtained, thereby obtaining the brightness decay relationship.

[0056] The test screen used to obtain the brightness decay relationship can be the same as the test screen used to obtain the current decay relationship, or they can be different. If the brightness decay relationship and the current decay relationship are obtained in different aging test stages, different test screens can be used to obtain the brightness decay relationship and the current decay relationship respectively. However, if the brightness decay relationship and the current decay relationship are obtained simultaneously in the same aging test, the same test screen can be used. In this case, the current value when multiple image blocks are displayed can be detected separately after a period of time, and the brightness value when multiple image blocks are displayed simultaneously can be detected, so as to obtain the brightness decay relationship and the current decay relationship simultaneously.

[0057] Specifically, refer to Figure 4 , Figure 4 A schematic diagram of the test screen used in the embodiments of this disclosure is shown, such as... Figure 4 As shown, in every 2×2 image blocks in the test screen, the two image blocks on the first diagonal are both black image blocks, and the two image blocks on the second diagonal are different in color and are different from the black image blocks; wherein, the first diagonal and the second diagonal are the two intersecting diagonals in the 2×2 image blocks.

[0058] In this embodiment, a 2×2 image block is considered as a single region. The two image blocks on the first diagonal are both black, so they are not illuminated when the test screen is displayed. The two image blocks on the second diagonal are of different colors and are not black, meaning the pixels in the area containing these two image blocks are illuminated. Multiple image blocks form a test screen resembling a chessboard pattern. Each color image block in this chessboard pattern is adjacent to four black image blocks. This reduces current interference between pixels displaying different colors, improves the accuracy of current detection, and facilitates the detection of brightness in different image blocks. It can be applied simultaneously to the process of obtaining brightness attenuation relationships and current attenuation relationships. For example, as... Figure 4 As shown, the image blocks of different colors can include a red image block R, a green image block G, and blue image blocks B1 and B2. The saturation of the two blue image blocks B1 and B2 can be different, so as to obtain the brightness attenuation relationship and current attenuation relationship when displaying different colors using this test screen.

[0059] In one embodiment, considering that the temperature of the display device also affects the current attenuation of the pixel driving current, the obtained display parameters may also include the current temperature of the display device. Then, the second compensation value corresponding to each pixel can be determined based on the cumulative display duration, the input grayscale corresponding to each pixel, the current temperature, and the current attenuation relationship.

[0060] In this embodiment, when obtaining the current attenuation relationship, i.e. when testing the display device, the current attenuation relationship corresponding to different temperatures can be obtained. When performing screen compensation on the display device, the current temperature of the display device can be obtained at the same time. Based on the input grayscale corresponding to each pixel and the current attenuation relationship at the current temperature, the corresponding second compensation value can be obtained based on the current attenuation relationship and the cumulative display time.

[0061] Of course, considering that pixel brightness decay is also affected by the temperature of the display device, when obtaining the brightness decay relationship, the brightness decay relationship corresponding to different temperatures can be determined. Then, when performing screen compensation on the display device, the corresponding brightness decay relationship can be determined based on the current temperature of the display device and the input grayscale corresponding to each pixel. Then, based on the brightness decay relationship and the cumulative display time, the corresponding first compensation value can be obtained.

[0062] In one embodiment, weights can be preset for the first compensation value and the second compensation value, and compensation can be performed according to the weights. Specifically, this process can be to first obtain the weights corresponding to the first compensation value and the second compensation value respectively; then, the first compensation value, the second compensation value and their respective weights are used to compensate the input grayscale corresponding to each pixel.

[0063] In this embodiment, the weights corresponding to the first compensation value and the second compensation value can be stored in advance. When performing image compensation, the weights corresponding to the first compensation value and the second compensation value can be obtained directly. The weights of the first compensation value and the second compensation value can be the same or different, and can be set according to the actual situation.

[0064] The image compensation method provided in this disclosure determines a first compensation value by pre-acquired brightness attenuation relationships, the input grayscale corresponding to each pixel, and the cumulative display duration; and determines a second compensation value by pre-acquired current attenuation relationships, the input grayscale corresponding to each pixel, and the cumulative display duration, and uses the first and second compensation values ​​to compensate the input grayscale of each pixel. Thus, during image compensation, both brightness attenuation and current attenuation of the pixel driving circuit are considered, improving compensation accuracy and thereby improving image quality. Furthermore, a method for determining current attenuation relationships is also provided, using a test screen comprising multiple image blocks, and lighting up multiple image blocks separately when detecting current, testing the current value of one image block at a time, providing reliable data support for accurately evaluating current attenuation.

[0065] The image compensation method provided in this disclosure embodiment will now be described with reference to a specific example: Before image compensation, an aging test can be performed on the display device to obtain the brightness decay relationship and the current decay relationship. The process of obtaining the current decay relationship can be as follows: First, the driver displays the test screen, so that... Figure 4 For example, the test screen can include 25 image blocks, all of which are the same size. Taking each 2×2 image block as an example, such as the four image blocks numbered 1, 2, 6, and 7, the two image blocks numbered 2 and 6, which are located on the diagonal, are both black images. The two image blocks numbered 1 and 7, which are located on the diagonal, are image blocks of different colors. Number 1 is a white image block and number 7 is a black image block. During the display of this test screen, the two lit image blocks are isolated by the black image blocks, which can prevent the driving current of the two adjacent image blocks from affecting each other when they are lit.

[0066] After a certain time interval, multiple image blocks in the test screen are displayed multiple times. During each display of an image block, the current of the display device is detected to determine the current value corresponding to the cumulative display duration. For example, refer to... Figure 5 , Figure 5 The diagram illustrates the images displayed by the display device at different times of illumination, such as... Figure 5 As shown, during a single lighting cycle, as Figure 5 As shown in Figure a, image block numbered 1 in the test screen is lit up, while the remaining image blocks are black. During another lighting test, as shown... Figure 5 As shown in Figure b, image block number 21 in the test screen is lit up, while the other image blocks are black. That is, when multiple image blocks in the test screen are displayed multiple times, only one image block is lit up each time to avoid the current of the other image blocks affecting the detection of the current corresponding to that image block.

[0067] After detecting the current of the display device, the display grayscale of the image block can be adjusted to obtain the current value corresponding to the image block under multiple display grayscales, which makes it convenient to obtain the current value corresponding to the cumulative display time under different grayscales; of course, each pixel of the display device generally includes red sub-pixels, green sub-pixels and blue sub-pixels, so the current value can be obtained when the image block emits red light, green light, blue light and white light respectively.

[0068] It is understandable that the temperature of the display device will also affect the degree of current attenuation in the pixel driving circuit, so it is also possible to obtain the current value corresponding to different cumulative display durations at different temperatures.

[0069] After obtaining the current values ​​corresponding to different cumulative display durations at different temperatures and gray levels, the current curves of the pixel driving circuit with cumulative display duration at different temperatures and gray levels can be determined, i.e., the current decay relationship.

[0070] Then, the display devices can be debugged under different temperatures and different gray levels for multiple cumulative display durations to obtain the second compensation value corresponding to each current value in the current attenuation relationship, thereby obtaining the second compensation table.

[0071] Similarly, when driving the display device to display the test screen, the brightness value of each image block can be obtained after a certain time interval to determine the brightness at different points on the display device. Of course, after each brightness test, the display grayscale of multiple image blocks can be adjusted to obtain the brightness of the display device under multiple different grayscales, thereby obtaining the brightness curve of the pixel under different grayscales as a function of cumulative time, i.e., the brightness decay relationship.

[0072] Then, the display devices under different gray levels and multiple cumulative display durations can be debugged to obtain the first compensation value corresponding to each brightness value in the brightness attenuation relationship, thereby obtaining the first compensation table.

[0073] During the display phase, the input grayscale corresponding to each pixel and the display parameters of the display device can be obtained from the image data to be displayed. These display parameters may include the cumulative display duration and the current temperature of the display device. Then, based on the cumulative display duration and the input grayscale of each pixel, the corresponding first compensation value is looked up from a first compensation value table. Similarly, based on the cumulative display duration, the input grayscale of each pixel, and the current temperature of the display device, the corresponding second compensation value is looked up from a second compensation value table. Next, the weights corresponding to the first and second compensation values ​​are obtained, and the input grayscale corresponding to each pixel is compensated. Finally, the compensated grayscale values ​​are used to drive the display device to display the image.

[0074] Based on the same inventive concept, this disclosure also provides a display device, referring to... Figure 6 , Figure 6 A schematic diagram of the structure of the display device provided in an embodiment of this disclosure is shown, such as... Figure 6 As shown, the display device 400 includes a display panel 410 and a driving display module; wherein the driving display module is used to perform the screen compensation method provided in any of the above embodiments.

[0075] In this embodiment, the display device is an OLED display device, and the driving display module is used to implement the image compensation method and drive the display panel 410 to display the image after compensation of grayscale value.

[0076] In one embodiment, the display device 400 further includes a storage unit storing a first compensation table and a second compensation table; The driver display module is also used to look up the first compensation value corresponding to the cumulative display duration and input grayscale from the first compensation table; And a second compensation value used to look up the cumulative display duration and input grayscale from the second compensation table; The first compensation table is obtained by fitting the brightness attenuation relationship, and the second compensation table is obtained by fitting the current attenuation relationship.

[0077] Specifically, refer to Figure 7 , Figure 7 A schematic diagram of the image compensation process in an embodiment of this disclosure is shown, such as... Figure 7 As shown, when the driving display module obtains the cumulative display duration and the input grayscale corresponding to each pixel, it can obtain the first compensation table and the second compensation table from the storage unit. Both the first compensation table and the second compensation table are LUT tables. The corresponding first compensation value and the second compensation value can be found according to the cumulative display duration and the input grayscale corresponding to each pixel. Then, the first compensation value and the second compensation value are used to compensate the input grayscale corresponding to each pixel, and then the compensated grayscale value is used to drive the display panel to display the image.

[0078] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0079] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0080] The above provides a detailed description of the image compensation method and display device provided by this disclosure. Specific examples have been used to illustrate the principles and implementation methods of this disclosure. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of this disclosure. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this disclosure. Therefore, the content of this specification should not be construed as a limitation of this disclosure.

[0081] Other embodiments of this disclosure will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This disclosure is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this disclosure are indicated by the following claims.

[0082] It should be understood that this disclosure is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this disclosure is limited only by the appended claims.

[0083] The terms "an embodiment," "embodiment," or "one or more embodiments" as used herein mean that a particular feature, structure, or characteristic described in connection with an embodiment is included in at least one embodiment of this disclosure. Furthermore, please note that the examples of the phrase "in one embodiment" do not necessarily all refer to the same embodiment.

[0084] Numerous specific details are set forth in the specification provided herein. However, it will be understood that embodiments of this disclosure may be practiced without these specific details. In some instances, well-known methods, structures, and techniques have not been shown in detail so as not to obscure the understanding of this specification.

[0085] In the claims, any reference signs placed between parentheses should not be construed as limiting the claims. The word "comprising" does not exclude the presence of elements or steps not listed in the claims. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. This disclosure can be implemented by means of hardware comprising a plurality of different elements and by means of a suitably programmed computer. In a unit claim enumerating a plurality of means, several of these means may be embodied by the same item of hardware. The use of the words first, second, and third, etc., does not indicate any order. These words may be interpreted as names.

[0086] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this disclosure, and are not intended to limit them. Although this disclosure has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this disclosure.

Claims

1. A method for image compensation, characterized in that, Applied to a display device, the display device including a plurality of pixels, each pixel including a pixel driving circuit, the method includes: From the image data to be displayed, obtain the input grayscale corresponding to each pixel and the display parameters of the display device, wherein the display parameters include the cumulative display duration of the display device; Based on the cumulative display duration, the input grayscale of each pixel, and the preset brightness attenuation relationship, a first compensation value corresponding to the input grayscale of each pixel is determined; wherein, the brightness attenuation relationship is used to characterize the relationship between the display brightness of the pixel and the cumulative display duration under different grayscale levels; Based on the cumulative display duration, the input grayscale corresponding to each pixel, and the preset current attenuation relationship, a second compensation value corresponding to the input grayscale of each pixel is determined; wherein, the current attenuation relationship is used to characterize the relationship between the current of the pixel driving circuit and the cumulative display duration under different grayscale levels; Based on the first compensation value and the second compensation value, the input grayscale corresponding to each pixel is compensated.

2. The image compensation method according to claim 1, characterized in that, The step of determining the first compensation value corresponding to the input grayscale of each pixel based on the cumulative display duration, the input grayscale of each pixel, and a preset brightness attenuation relationship includes: Obtain a first compensation table, which is obtained by fitting the brightness attenuation relationship; wherein, the first compensation table includes compensation values ​​corresponding to different cumulative display durations and different input gray levels; Find the first compensation value corresponding to the cumulative display duration and the input grayscale from the first compensation table.

3. The image compensation method according to claim 1, characterized in that, The step of determining the second compensation value corresponding to the input grayscale of each pixel based on the cumulative display duration, the input grayscale corresponding to each pixel, and a preset current attenuation relationship includes: Obtain a second compensation table, which is obtained by fitting the current attenuation relationship; wherein, the second compensation table includes compensation values ​​corresponding to different cumulative display durations and different input gray levels; Find the second compensation value corresponding to the cumulative display duration and the input grayscale from the second compensation table.

4. The brightness compensation method according to claim 1, characterized in that, The current decay relationship is determined through the following steps: The display device is driven to display a test screen, which includes multiple image blocks; Multiple image blocks are lit up respectively, and when each image block is lit up, the current value of the image block under different gray levels and different cumulative display durations is detected; The current attenuation relationship is determined based on the change of the current value with the grayscale and the cumulative display duration.

5. The image compensation method according to claim 4, characterized in that, The step of lighting up multiple image blocks respectively includes: Multiple image blocks are illuminated in several stages, with different image blocks illuminated each time. When the image block is lit up, among the multiple image blocks, the image blocks other than the lit image block are displayed as black.

6. The image compensation method according to claim 1, characterized in that, The method for obtaining the brightness attenuation relationship includes: The test screen is displayed using the aforementioned display device, and the test screen includes multiple image blocks; wherein the display colors of the multiple image blocks are not exactly the same; Obtain the brightness values ​​of the display device at different gray levels and different cumulative display durations; Based on the brightness values ​​corresponding to the multiple gray levels and the multiple cumulative display durations, the change of the brightness value with respect to the gray levels and the cumulative display duration is determined; The brightness attenuation relationship is determined based on the change of the brightness value with the grayscale and the cumulative display duration.

7. The image compensation method according to claim 4 or 6, characterized in that, In every 2×2 image blocks in the test screen, the two image blocks on the first diagonal are both black image blocks, and the two image blocks on the second diagonal are different in color from the black image blocks. The first diagonal and the second diagonal are two intersecting diagonals in a 2×2 image block.

8. The image compensation method according to claim 1, characterized in that, The display parameters also include the current temperature of the display device; The step of determining the second compensation value corresponding to the input grayscale of each pixel based on the cumulative display duration, the input grayscale corresponding to each pixel, and a preset current attenuation relationship includes: Based on the cumulative display duration, the input grayscale corresponding to each pixel, the current temperature, and the current attenuation relationship, a second compensation value is determined for each pixel.

9. The image compensation method according to claim 1, characterized in that, The step of compensating the input grayscale corresponding to each pixel based on the first compensation value and the second compensation value includes: Obtain the weights corresponding to the first compensation value and the second compensation value, respectively; The input grayscale corresponding to each pixel is compensated using the first compensation value, the second compensation value, and their respective weights.

10. A display device, characterized in that, This includes the display panel and the display driver module; The driving display module is used to perform the screen compensation method as described in any one of claims 1-9.

11. The display device according to claim 11, characterized in that, It also includes a storage unit, which stores a first compensation table and a second compensation table; The driving display module is also used to look up the first compensation value corresponding to the cumulative display duration and input grayscale from the first compensation table; And a second compensation value used to look up the cumulative display duration and input grayscale from the second compensation table; The first compensation table is obtained by fitting the brightness attenuation relationship, and the second compensation table is obtained by fitting the current attenuation relationship.

Images