Display panel and brightness compensation method thereof

Abstract

The application discloses a display panel and a brightness compensation method thereof. The method comprises the following steps: for any sub-pixel in the edge display area, determining a first compensation value corresponding to the sub-pixel of the edge display area according to the display brightness value of the display panel and the gray scale of the sub-pixel under the display brightness value; the first compensation value is related to the product of the actual brightness of the gray scale of the sub-pixel under the display brightness value and the compensation coefficient corresponding to the sub-pixel; in the edge display area, the compensation coefficients corresponding to each sub-pixel arranged in the direction of the edge display area pointing to the middle display area monotonously change. The actual brightness of the sub-pixel under the gray scale is multiplied by the compensation coefficient to obtain a new actual brightness, and then the corresponding first compensation value is determined according to the new actual brightness, so that the display law of the screen body under a lower display brightness value can be considered, the compensation effect of the display panel under each display brightness value is better, and the display uniformity is improved.

Description

Technical Field

[0001] This invention relates to the field of display technology, and more particularly to display panels and their brightness compensation methods. Background Technology

[0002] Organic light-emitting diode (OLED) displays possess numerous advantages such as self-illumination and high contrast, making them a promising display technology with broad application prospects. Traditional OLED products utilize low-temperature polycrystalline silicon (LTPS) technology. However, LTPS is limited by the relatively high leakage current of transistor devices, leading to noticeable flickering in low-frequency applications. Low-temperature polycrystalline oxide (LTPO) technology has emerged to address this issue. LTPO combines the high mobility of LTPS with the low leakage current characteristics of oxides, enabling both high-frequency and low-frequency applications, thus gaining market favor.

[0003] However, existing screens, such as LTPO screens, are prone to uneven display due to problems such as transistor leakage. Although existing technologies compensate for uneven display, the compensation effect is poor and the display quality is not high. Summary of the Invention

[0004] This invention provides a display panel and its brightness compensation method to solve the problem of uneven display on the display panel.

[0005] According to one aspect of the present invention, a brightness compensation method for a display panel is provided, the display panel including an edge display area and a central display area, the edge display area being disposed around the central display area;

[0006] The brightness compensation method for the display panel includes:

[0007] For any sub-pixel in the edge display area, a first compensation value corresponding to the sub-pixel in the edge display area is determined based on the display brightness value of the display panel and the grayscale of the sub-pixel under the display brightness value.

[0008] The first compensation value is related to the product of the actual brightness of the sub-pixel at the gray level under the display brightness value and the compensation coefficient corresponding to the sub-pixel. In the edge display area, the compensation coefficients corresponding to each sub-pixel arranged along the direction from the edge display area to the middle display area change monotonically. For any sub-pixel in the edge display area, the first compensation value corresponding to the same gray level under different display brightness values ​​is different.

[0009] Optionally, in the edge display area, the compensation coefficients corresponding to each sub-pixel in the edge display area, arranged along the direction from the edge display area to the central display area, satisfy a linear monotonic change.

[0010] Optionally, in the edge display area, the compensation coefficients corresponding to each sub-pixel in the edge display area arranged along the direction from the edge display area to the middle display area satisfy a polynomial monotonic change.

[0011] Optionally, in the edge display area, the compensation coefficient corresponding to each sub-pixel in the edge display area arranged along the direction from the edge display area to the middle display area changes monotonically from 0.5 to 1, or the compensation coefficient corresponding to each sub-pixel in the edge display area arranged along the direction from the edge display area to the middle display area changes monotonically from 1.5 to 1.

[0012] Optionally, for any sub-pixel in the edge display area, determining the first compensation value corresponding to the sub-pixel in the edge display area based on the display brightness value of the display panel and the grayscale of the sub-pixel in the edge display area under the display brightness value includes:

[0013] For any sub-pixel in the edge display area, the first compensation value corresponding to the sub-pixel in the edge display area is determined based on the display brightness value of the display panel, the grayscale of the sub-pixel in the edge display area under the display brightness value, and the first preset correspondence relationship corresponding to the sub-pixel in the edge display area under the display brightness value; the first preset correspondence relationship is the correspondence relationship between grayscale and first compensation value.

[0014] Optionally, for any sub-pixel in the edge display area, determining the first compensation value corresponding to the sub-pixel in the edge display area based on the display brightness value of the display panel, the grayscale of the sub-pixel in the edge display area at the display brightness value, and the first preset correspondence relationship corresponding to the sub-pixel in the edge display area at the display brightness value includes:

[0015] The display panel includes multiple reference display brightness values ​​and a reference first preset correspondence relationship for each of the reference display brightness values;

[0016] When the display brightness value of the display panel is equal to any of the reference display brightness values, the first compensation value is determined according to the reference first preset correspondence between the sub-pixels of the edge display area and the grayscale of the sub-pixels of the edge display area under the display brightness value.

[0017] When the display brightness value of the display panel is not equal to any of the reference display brightness values, the first compensation value corresponding to the sub-pixel of the edge display area in the grayscale under the display brightness value is determined by interpolation calculation.

[0018] Optionally, the display panel includes multiple display brightness ranges, and each display brightness range includes at least one reference display brightness value;

[0019] Before determining the first compensation value corresponding to the sub-pixels of the edge display area based on the display brightness value of the display panel, the grayscale of the sub-pixels of the edge display area under the display brightness value, and the first preset correspondence relationship corresponding to the sub-pixels of the edge display area under the display brightness value, the method further includes:

[0020] Obtain the brightness grayscale curve of each sub-pixel in the display panel at each of the reference display brightness values; the brightness grayscale curve is the relationship curve between grayscale and the actual brightness of the sub-pixel.

[0021] For any grayscale of any sub-pixel in the edge display area at any reference display brightness value, the actual brightness of the sub-pixel in the grayscale of the reference display brightness value is determined based on the brightness grayscale curve corresponding to the sub-pixel in the edge display area at the reference display brightness value and the grayscale of the sub-pixel in the edge display area at the reference display brightness value.

[0022] The first compensation value of the sub-pixel of the edge display area under the grayscale of the reference display brightness value is generated based on the product of the actual brightness of the sub-pixel of the edge display area under the grayscale of the reference display brightness value and the compensation coefficient corresponding to the sub-pixel of the edge display area, and the target brightness corresponding to the grayscale of the reference display brightness value.

[0023] For any reference display brightness value of any sub-pixel in the edge display area, the reference first preset correspondence relationship corresponding to the reference display brightness value is generated based on each gray level under the reference display brightness value and the first compensation value corresponding to each gray level.

[0024] Optionally, for any grayscale under any of the reference display brightness values, the actual brightness of the sub-pixel located at the middle position of the display panel corresponding to the grayscale under the reference display brightness value is taken as the target brightness.

[0025] Optionally, the brightness compensation method for the display panel also includes:

[0026] For any sub-pixel of the intermediate display area, a second compensation value corresponding to the sub-pixel of the intermediate display area at the gray level of the display brightness value is determined based on the display brightness value of the display panel, the gray level of the sub-pixel of the intermediate display area at the display brightness value, and the second preset correspondence relationship corresponding to the sub-pixel of the intermediate display area at the display brightness value. The second preset correspondence relationship is the correspondence relationship between the gray level and the second compensation value.

[0027] Optionally, for any sub-pixel in the intermediate display area, the second compensation value corresponding to the same grayscale under different display brightness values ​​is different.

[0028] Optionally, determining the second compensation value corresponding to the sub-pixel of the intermediate display area at the grayscale of the display brightness value based on the display brightness value of the display panel, the grayscale of the sub-pixel of the intermediate display area at the display brightness value, and the second preset correspondence relationship corresponding to the sub-pixel of the intermediate display area at the display brightness value includes:

[0029] When the display brightness value of the display panel is equal to any of the reference display brightness values, the second compensation value corresponding to the sub-pixels of the intermediate display area under the grayscale of the display brightness value is determined according to the reference second preset correspondence relationship corresponding to the reference display brightness value and the grayscale of the sub-pixels of the intermediate display area under the display brightness value.

[0030] When the display brightness value of the display panel is not equal to any of the reference display brightness values, the second compensation value corresponding to the sub-pixel of the intermediate display area in the grayscale of the display brightness value is determined by interpolation calculation.

[0031] Optionally, before determining the second compensation value corresponding to the grayscale of the sub-pixels in the display brightness value based on the display brightness value of the display panel, the grayscale of the sub-pixels in the middle display area at the display brightness value, and the second preset correspondence relationship corresponding to the sub-pixels in the middle display area at the display brightness value, the method further includes:

[0032] For any grayscale of any sub-pixel in the intermediate display area at any reference display brightness value, the actual brightness of the sub-pixel in the intermediate display area at the grayscale of the reference display brightness value is determined based on the brightness grayscale curve corresponding to the sub-pixel in the intermediate display area at the reference display brightness value and the grayscale at the reference display brightness value.

[0033] A second compensation value is generated based on the actual brightness of the sub-pixels in the grayscale of the reference display brightness value and the target brightness corresponding to the grayscale of the reference display brightness value.

[0034] For any reference display brightness value of any sub-pixel in any of the intermediate display areas, a reference second preset correspondence relationship is generated based on each gray level under the reference display brightness value and the second compensation value corresponding to each gray level.

[0035] Optionally, each of the aforementioned reference display brightness values ​​includes at least two bounding grayscale levels;

[0036] Before obtaining the luminance grayscale curve of each sub-pixel corresponding to each of the reference display luminance values, the following steps are also included:

[0037] For any of the aforementioned reference display brightness values, the display panel is sequentially illuminated using at least two bounding grayscale values ​​under the aforementioned reference display brightness value.

[0038] Obtain the actual brightness of each of the binding point grayscales of each sub-pixel in the display panel under the reference display brightness value;

[0039] For any sub-pixel, a brightness grayscale curve is generated based on the grayscale of each binding point and the actual brightness under each binding point grayscale.

[0040] According to another aspect of the present invention, a display panel is provided, wherein the brightness compensation method of the display panel described above is used for brightness compensation.

[0041] The technical solution of this invention, on the one hand, determines the first compensation value corresponding to the sub-pixel based on the display brightness value. Different first compensation values ​​correspond to different display brightness values, thereby improving the compensation effect. On the other hand, considering that the edge display area exhibits a gradual brightness change trend along the direction from the edge display area to the center display area, when the display panel generates the first compensation value corresponding to the grayscale in the early stage, the actual brightness of the sub-pixel at the grayscale is multiplied by a compensation coefficient to obtain the new actual brightness. Then, the corresponding first compensation value is determined based on the new actual brightness. This allows the display pattern of the screen at lower display brightness values ​​to be taken into account, resulting in a better compensation effect of the display panel at various display brightness values, thereby improving display uniformity.

[0042] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0043] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0044] Figure 1 This is a schematic diagram of the structure of a display panel provided in an embodiment of the present invention;

[0045] Figure 2 A flowchart illustrating a brightness compensation method for a display panel provided in an embodiment of the present invention;

[0046] Figure 3 A flowchart of another brightness compensation method for a display panel provided in an embodiment of the present invention;

[0047] Figure 4 A schematic diagram of the brightness grayscale curve of a sub-pixel provided in an embodiment of the present invention;

[0048] Figure 5 A diagram showing the correspondence between compensation coefficients and sub-pixel positions is provided in an embodiment of the present invention.

[0049] Figure 6 A flowchart of another brightness compensation method for a display panel provided in an embodiment of the present invention;

[0050] Figure 7 A flowchart of another brightness compensation method for a display panel provided in an embodiment of the present invention. Detailed Implementation

[0051] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0052] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0053] As described in the background section, existing technologies have poor compensation effects for display unevenness. The inventors discovered that this is because, during brightness compensation, different display brightness values ​​are compensated using the same grayscale and compensation value correspondence. Mobile phones, computers, and other display devices typically include brightness adjustment buttons, which users use to change the input display brightness value (DBV), also known as a display brightness level. Each display brightness value corresponds to a brightness level of the maximum grayscale in the display panel. Changing the brightness corresponding to the maximum grayscale in the display panel will change the brightness of other grayscale levels. Specifically, when the brightness corresponding to the maximum grayscale in the display panel increases, the brightness of other grayscale levels also increases; conversely, when the brightness corresponding to the maximum grayscale in the display panel decreases, the brightness of other grayscale levels also decreases. Therefore, it can also be understood that each input display brightness value corresponds to a brightness level of the display panel. When the display brightness corresponding to the maximum gray level in the display panel is large, the brightness level is large and the overall display brightness of the display panel is large; when the display brightness corresponding to the maximum gray level in the display panel is small, the brightness level is small and the overall display brightness of the display panel is small.

[0054] In existing technologies, to compensate for display unevenness in display panels, a display brightness value is selected and designated as a reference brightness value. The correspondence between each grayscale level and the compensation value is determined under this reference brightness value. Subsequently, during the display process, regardless of the brightness value of the display panel, the correspondence between grayscale levels and compensation values ​​is always based on the reference brightness value. This results in all brightness values ​​having the same set of correspondences, leading to poor compensation. Furthermore, existing display panels, when compensating for display unevenness, typically use a higher brightness value to determine the correspondence between grayscale levels and compensation values. At higher brightness values, the brightness consistency between sub-pixels in the edge display area and those in the center display area is high. However, at lower brightness values, due to manufacturing processes, the brightness difference between sub-pixels in the edge display area and those in the center display area is significant. If the correspondence from a higher brightness value is used to determine the compensation value at lower brightness values, the compensation effect will be unsatisfactory.

[0055] To address the aforementioned technical problems, embodiments of the present invention provide a brightness compensation method for a display panel to solve the problems of uneven display and poor compensation effect.

[0056] Figure 1 This is a schematic diagram of the structure of a display panel provided in an embodiment of the present invention, with reference to... Figure 1 The display panel includes an edge display area 1 and a central display area 2, with the edge display area 1 surrounding the central display area 2. Both the edge display area 1 and the central display area 2 contain an array of sub-pixels for display. The edge display area 1 can be the area extending along the row direction of the sub-pixel arrangement, from the first sub-pixel at the edge of the display panel 3, in a direction pointing towards the central display area 2, to the m-th sub-pixel; and along the column direction of the sub-pixel arrangement, from the first sub-pixel at the edge of the display panel, in a direction pointing towards the central display area 2, to the h-th sub-pixel, where m and h are both integers greater than or equal to 2. Optionally, if the display panel includes a rows and b columns of sub-pixels, then m = 0.2 * b, h = 0.2 * a, where a and b are both integers greater than or equal to 2.

[0057] Figure 2 A flowchart of a brightness compensation method for a display panel provided in an embodiment of the present invention is shown below. Figure 1 and Figure 2 The method includes:

[0058] S110: For any sub-pixel in the edge display area, determine the first compensation value corresponding to the sub-pixel in the edge display area based on the display brightness value of the display panel and the grayscale of the sub-pixel under the display brightness value.

[0059] The first compensation value is related to the product of the actual brightness of the grayscale of the sub-pixel under the display brightness value and the compensation coefficient corresponding to the sub-pixel. In the edge display area 1, the compensation coefficients of each sub-pixel arranged along the direction from the edge display area 1 to the middle display area 2 change monotonically.

[0060] For any sub-pixel in the edge display area 1, the first compensation value corresponding to the same gray level is different under different display brightness values.

[0061] For any sub-pixel in the edge display area 1, under a given display brightness value, the grayscale corresponds one-to-one with the first compensation value. Furthermore, for the same grayscale, the corresponding first compensation value differs under different display brightness values. This allows for the use of different correspondences to determine the first compensation value for the grayscale under different display brightness values, improving compensation accuracy. When the display panel is in the normal display phase, before displaying the next frame, the display brightness value of the display panel in the next display frame and the grayscale of any sub-pixel in the edge display area 1 are obtained. Once the display brightness value is determined, the grayscale corresponds one-to-one with the first compensation value. Therefore, the first compensation value corresponding to the sub-pixel can be determined based on the display brightness value and the grayscale. In an optional implementation, for any sub-pixel in the edge display area 1, when the first compensation value corresponding to the grayscale of the sub-pixel under a certain display brightness value is determined earlier, the actual brightness corresponding to the grayscale of the sub-pixel under that display brightness value is obtained. Then, the first compensation value corresponding to the grayscale of the sub-pixel under that display brightness value is determined based on the product of the actual brightness and the compensation coefficient corresponding to the sub-pixel. The compensation coefficient is independent of both the display brightness value and grayscale; it is only related to the distance of the sub-pixel from the central display area 2. During the sub-pixel fabrication process, due to processes such as vapor deposition, the display brightness of sub-pixels in the edge display area 1 at lower display brightness values ​​differs significantly from that of sub-pixels in the central display area 2. Most sub-pixels in the edge display area 1 exhibit a monotonic brightness variation corresponding to each sub-pixel arranged along the direction from the edge display area 1 to the central display area 2. That is, at the same grayscale with the same display brightness value, the sub-pixels in the edge display area 1 show a gradual brightness change trend in the direction from the edge display area 1 to the central display area 2.

[0062] When determining the first compensation value for the sub-pixels of the edge display area 1, a medium or high display brightness value, such as the actual brightness of the grayscale at 500 nits, is generally selected. At medium or high display brightness values, the actual brightness of the sub-pixels of the edge display area 1 at a certain grayscale is not significantly different from the actual brightness of the sub-pixels of the middle display area 2, resulting in a relatively small first compensation value. However, at lower display brightness values, such as 2 nits, the actual brightness of the sub-pixels of the edge display area 1 at a certain grayscale differs significantly from the actual brightness of the sub-pixels of the middle display area 2, and the brightness of the sub-pixels of the edge display area 1 exhibits a gradual change. If, at this point, the brightness of the sub-pixels of the edge display area 1 is still compensated based on the actual brightness at a higher display brightness value, or if the first compensation value determined based on the actual brightness at a higher display brightness value is used for interpolation calculation to compensate the brightness of the sub-pixels of the edge display area 1, both methods result in insufficient compensation, i.e., undercompensation. Therefore, to conform to the direction from the edge display area 1 to the central display area 2 under other display brightness values, the edge display area 1 exhibits a gradual brightness change trend. The actual brightness is multiplied by a compensation coefficient to obtain the new actual brightness. Based on the new actual brightness, the corresponding first compensation value is determined, thereby solving the undercompensation problem and improving the display effect. Specifically, whether the sub-pixels of the edge display area 1 exhibit a gradual brightening or dimming trend in the direction from the edge display area 1 to the central display area 2 is determined by the screen itself.

[0063] The technical solution of this invention, on the one hand, determines the first compensation value corresponding to the sub-pixel based on the display brightness value. Different first compensation values ​​correspond to different display brightness values, thereby improving the compensation effect. On the other hand, considering that the edge display area exhibits a gradual brightness change trend along the direction from the edge display area to the center display area, when the display panel generates the first compensation value corresponding to the grayscale in the early stage, the actual brightness of the sub-pixel at the grayscale is multiplied by a compensation coefficient to obtain the new actual brightness. Then, the corresponding first compensation value is determined based on the new actual brightness. This allows the display pattern of the screen at lower display brightness values ​​to be taken into account, resulting in a better compensation effect of the display panel at various display brightness values, thereby improving display uniformity.

[0064] Figure 3 A flowchart of another brightness compensation method for a display panel provided in an embodiment of the present invention is shown below. Figure 1 and Figure 3 The method includes:

[0065] S111: Obtain the brightness grayscale curve of each sub-pixel in the display panel at each reference display brightness value; the brightness grayscale curve is the relationship curve between grayscale and the actual brightness of the sub-pixel.

[0066] Figure 4 This is a schematic diagram of a sub-pixel's brightness grayscale curve provided in an embodiment of the present invention. The horizontal axis represents the grayscale level, and the vertical axis represents the actual brightness of the sub-pixel. After generating the brightness grayscale curve, the actual brightness of the sub-pixel at any grayscale level can be obtained.

[0067] The display panel includes multiple display brightness ranges, each including at least one reference display brightness value. The display panel is divided into multiple display brightness ranges from its minimum to its maximum display brightness value. For example, if the maximum display brightness value is 1200 nits and the minimum display brightness value is 0 nits, the display panel is divided into four display brightness ranges: 0-2 nits, 2 nits-90 nits, 90 nits-500 nits, and 500 nits-1200 nits. A reference display brightness value is selected from each display brightness range; for example, the four selected reference display brightness values ​​are 1 nit, 50 nits, 300 nits, and 800 nits. The corresponding grayscale curve for each reference display brightness value is then obtained.

[0068] S121: For any grayscale of any sub-pixel in the edge display area under any reference display brightness value, determine the actual brightness of the sub-pixel in the edge display area under the grayscale of the reference display brightness value based on the brightness grayscale curve corresponding to the sub-pixel in the edge display area under the reference display brightness value and the grayscale of the sub-pixel in the edge display area under the reference display brightness value.

[0069] Once the grayscale curve corresponding to the reference display brightness value is determined, the actual brightness corresponding to any grayscale level under that reference display brightness value can be determined. For example, if the reference display brightness value is 300 nits, the actual brightness corresponding to any grayscale level of the sub-pixel at 300 nits can be determined based on the grayscale curve corresponding to the sub-pixel at 300 nits.

[0070] S131: Generate the first compensation value of the sub-pixel of the edge display area in the grayscale of the reference display brightness value based on the product of the actual brightness of the sub-pixel of the edge display area in the grayscale of the reference display brightness value and the compensation coefficient corresponding to the sub-pixel of the edge display area, and the target brightness corresponding to the grayscale of the reference display brightness value.

[0071] In edge display area 1, each sub-pixel corresponds one-to-one with the product of its compensation coefficient. Before generating the first compensation value for each grayscale level under the reference display brightness value, the entire display panel is illuminated with any grayscale level, such as grayscale 128, at a smaller display brightness value, such as 2 nits. The actual brightness of each sub-pixel in the display panel is obtained. Based on the actual brightness of each sub-pixel, the display pattern of the sub-pixels in edge display area 1 and the display difference between them and the sub-pixels in the central display area 2 can be determined. This allows us to determine whether the compensation coefficients of each sub-pixel arranged along the direction from edge display area 1 to central display area 2 in the edge display area are monotonically increasing or monotonically decreasing. Optionally, the compensation coefficients of each sub-pixel arranged along the direction from edge display area 1 to central display area 2 can change monotonically from 0.5 to 1, which can be a uniform monotonic change. Alternatively, the compensation coefficients of each sub-pixel arranged along the direction from edge display area 1 to central display area 2 can change monotonically from 1.5 to 1, which can also be a uniform monotonic change. Assuming a monotonically increasing compensation coefficient, and considering a display panel comprising 1000 rows and 1000 columns of sub-pixels, with the edge display area 1 of the display panel comprising four sub-areas: a first sub-area 11 and a second sub-area 12, and two sub-areas 13 and 14, arranged opposite to each other. The first and second sub-areas 11 and 12 are arranged along the column direction of the sub-pixels, forming the top and bottom borders of the display area. The third and fourth sub-areas 13 and 14 are arranged along the row direction of the sub-pixels, forming the left and right borders of the display area. Taking the third sub-area 13 as an example, for any row of sub-pixels within the third sub-area 13, the compensation coefficient for the first sub-pixel at the edge of the display panel is 0.5, and the compensation coefficient for the sub-pixel closest to the center display area 2 in the edge display area 1 is 1. Therefore, the compensation coefficient for each sub-pixel from the first to the last sub-pixel in the edge display area 1 uniformly changes from 0.5 to 1.

[0072] In edge display area 1, the compensation coefficients of each sub-pixel of edge display area 1 arranged along the direction from edge display area 1 to the central display area 2 satisfy a linear monotonically changing condition, such as monotonically changing from 0.5 to 1. For any row of sub-pixels in edge display area 1, the difference between the compensation coefficients of any two adjacent sub-pixels is equal. Alternatively, in edge display area 1, the compensation coefficients of each sub-pixel of edge display area 1 arranged along the direction from edge display area 1 to the central display area 2 satisfy a polynomial monotonically changing condition. This polynomial monotonically changing condition of the compensation coefficients makes the display of edge display area 1 smoother after compensation, improving the display effect. In edge display area 1, sub-pixels equidistant from the central display area 2 (specifically, sub-pixels in the center of the display panel) have the same compensation coefficient.

[0073] Figure 5 This is a diagram showing the correspondence between compensation coefficients and sub-pixel positions, provided in an embodiment of the present invention. The horizontal axis represents the sub-pixel position in the horizontal direction, and the vertical axis represents the magnitude of the compensation coefficient. Figure 5 This includes a first curve 4 and a second curve 5, both of which are horizontal and represent the correspondence between sub-pixels of the edge display area 1 and their compensation coefficients. Within the edge display area 1, the compensation coefficients corresponding to each sub-pixel of the edge display area 1, arranged along the direction from the edge display area 1 to the central display area 2, exhibit a linear monotonically changing relationship, as detailed in the first curve 4. Alternatively, within the edge display area 1, the compensation coefficients corresponding to each sub-pixel of the edge display area 1, arranged along the direction from the edge display area 1 to the central display area 2, exhibit a multiplicative monotonically changing relationship, such as a quadratic monotonically changing relationship, as detailed in the second curve 5.

[0074] The compensation coefficient for a sub-pixel in the edge display area 1 is determined based on its position, or distance from the central display area 2. A first compensation value is determined by the difference between the product of the sub-pixel's actual brightness at the grayscale of the display brightness value and its corresponding compensation coefficient, and the target brightness at that grayscale. Specifically, for any grayscale at any reference display brightness value, the actual brightness of the sub-pixel located in the center of the display panel at that grayscale is taken as the target brightness. The first compensation value can be a compensation amount for the data voltage.

[0075] S141: For any reference display brightness value of any sub-pixel in the edge display area, generate a reference first preset correspondence relationship corresponding to the reference display brightness value based on each gray level under the reference display brightness value and the first compensation value corresponding to each gray level.

[0076] For any reference display brightness value, the corresponding first reference preset correspondence includes each gray level under the reference display brightness value and the first compensation value corresponding to each gray level.

[0077] S151: For any sub-pixel in the edge display area, determine the first compensation value corresponding to the sub-pixel in the edge display area based on the display brightness value of the display panel, the grayscale of the sub-pixel in the edge display area under the display brightness value, and the first preset correspondence relationship of the sub-pixel in the edge display area under the display brightness value.

[0078] For any sub-pixel in the edge display area 1, the display panel stores the correspondence between multiple gray levels and the first compensation value under different reference display brightness values. Therefore, for any sub-pixel in the edge display area 1, after obtaining the display brightness value and gray level of the display panel in the next display frame, the correspondence between the gray level and the first compensation value of the display panel in the next display frame can be determined based on the correspondence between the gray levels and the first compensation value under the multiple reference display brightness values ​​stored in the display panel, thereby determining the magnitude of the first compensation value.

[0079] Specifically, the display panel includes multiple reference display brightness values ​​and a first preset correspondence between each reference display brightness value. When the display brightness value of the display panel is equal to any reference display brightness value, a first compensation value is determined based on the first preset correspondence between the sub-pixels of the edge display area and the grayscale of the sub-pixels of the edge display area under the display brightness value. When the display brightness value of the display panel is not equal to any reference display brightness value, the first compensation value corresponding to the grayscale of the sub-pixels of the edge display area under the display brightness value is determined by interpolation calculation.

[0080] For example, three display brightness values ​​are selected from multiple display brightness values ​​as reference display brightness values, such as 50 nit, 300 nit, and 800 nit as reference display brightness values. Then, the first preset correspondence between the grayscale and the first compensation value under the above three reference display brightness values ​​is determined, and the first preset correspondence corresponding to the reference display brightness value is recorded as the reference first preset correspondence.

[0081] When the display panel's brightness value in the next display frame is 300 nits, the first compensation value corresponding to the sub-pixel in the grayscale of the next display frame is determined directly based on the reference first preset correspondence corresponding to 300 nits. When the display panel's brightness value in the next display frame is not equal to any reference display brightness value, the first compensation value corresponding to the grayscale of the sub-pixel in the next display frame is determined by interpolation calculation based on the reference first preset correspondence corresponding to the two reference display brightness values ​​closest to the display brightness value of the next display frame. Specifically, the display brightness value of the next display frame is taken as the two nearest reference display brightness values ​​and denoted as the first reference display brightness value and the second reference display brightness value. The gray level of the sub-pixel in the next display frame is denoted as the target gray level. Then, a first compensation value is determined according to the first reference preset correspondence of the target gray level under the first reference display brightness value and denoted as the first value. A first compensation value is determined according to the first reference preset correspondence of the target gray level under the second reference display brightness value and denoted as the second value. Then, the first compensation value of the display brightness value of the next display frame under the target gray level is determined by interpolation, such as linear interpolation, based on (first reference display brightness value, first value) and (second reference display brightness value, second value).

[0082] In embodiments of the present invention, all display brightness values ​​of the display panel are divided into multiple display brightness intervals. For each display brightness interval, at least one reference display brightness value is selected, and a first preset correspondence is determined for each reference display brightness value. This allows for the determination of the first preset correspondence for the display brightness value of the next display frame based on each reference display brightness value during practical application. The uneven display appearance of the display panel differs between lower and higher display brightness values. By dividing the display panel into multiple brightness intervals and determining the first preset correspondence for at least one reference display brightness value in each interval, the first preset correspondence for the next display frame is determined based on the first preset correspondence of the multiple reference display brightness values, thereby determining a first compensation value. This approach improves the brightness compensation effect by considering the inconsistency in the uneven display appearance of the display panel at different display brightness values.

[0083] Figure 6 A flowchart of another brightness compensation method for a display panel provided in an embodiment of the present invention is shown below. Figure 1 and Figure 6 The method includes:

[0084] S112: For any sub-pixel in the edge display area, determine the first compensation value corresponding to the sub-pixel in the edge display area based on the display brightness value of the display panel, the grayscale of the sub-pixel in the edge display area under the display brightness value, and the first preset correspondence relationship of the sub-pixel in the edge display area under the display brightness value.

[0085] S122: For any sub-pixel in the middle display area, based on the display brightness value of the display panel, the grayscale of the sub-pixel in the middle display area under the display brightness value, and the second preset correspondence relationship of the sub-pixel in the middle display area under the display brightness value, determine the second compensation value corresponding to the grayscale of the sub-pixel in the middle display area under the display brightness value. The second preset correspondence relationship is the correspondence between the grayscale and the second compensation value.

[0086] For any sub-pixel in the intermediate display area 2, the display panel stores the correspondence between multiple gray levels and the second compensation value under different reference display brightness values. Therefore, for any sub-pixel in the intermediate display area 2, after obtaining the display brightness value and gray level of the display panel in the next display frame, the correspondence between the gray level and the second compensation value of the display panel in the next display frame can be determined based on the correspondence between the gray levels and the second compensation value under the multiple reference display brightness values ​​stored in the display panel, thereby determining the magnitude of the second compensation value. For any sub-pixel in the intermediate display area, the second compensation value corresponding to the same gray level under different display brightness values ​​is different.

[0087] Specifically, S122 can be further refined as follows: When the display brightness value of the display panel is equal to any reference display brightness value, the second compensation value corresponding to the sub-pixel of the intermediate display area 2 in the grayscale of the display brightness value is determined according to the reference second preset correspondence corresponding to the reference display brightness value and the grayscale of the sub-pixel of the intermediate display area 2 in the display brightness value; when the display brightness value of the display panel is not equal to any reference display brightness value, the second compensation value corresponding to the sub-pixel of the intermediate display area 2 in the grayscale of the display brightness value is determined by interpolation calculation. The specific process is similar to that of determining the first compensation value in S151, and will not be repeated here.

[0088] For any reference display brightness value, the corresponding second reference preset correspondence includes each gray level under the reference display brightness value and the second compensation value corresponding to each gray level.

[0089] Figure 7 A flowchart of another brightness compensation method for a display panel provided in an embodiment of the present invention is shown below. Figure 1 and Figure 7 Optionally, the method includes:

[0090] S113: For any reference display brightness value, sequentially illuminate the display panel using at least two bound point grayscale values ​​under the reference display brightness value.

[0091] For example, taking a reference display brightness value of 300 nits as an example, the grayscale of the display panel includes 0-255 grayscale levels. Grayscale levels 16, 64, and 192 are all used as binding grayscale levels. The display panel is lit up with grayscale level 16, grayscale level 32, and grayscale level 192 in sequence.

[0092] S123: Obtain the actual brightness of each sub-pixel in the display panel at each bound point grayscale under the reference display brightness value.

[0093] After the display panel is lit up at each grayscale of the bound point, the camera captures the lit image for any given grayscale of the bound point, and then extracts the actual brightness of each sub-pixel.

[0094] S133: For any sub-pixel, generate a brightness grayscale curve based on the grayscale of each binding point and the actual brightness under each binding point grayscale.

[0095] For any sub-pixel, after acquiring three data points—namely, the actual brightness at grayscale level 16, grayscale level 32, and grayscale level 192—a brightness grayscale curve is generated by fitting these data points together. Figure 4 As shown.

[0096] S143: For any grayscale of any sub-pixel in the edge display area under any reference display brightness value, determine the actual brightness of the sub-pixel in the edge display area under the grayscale of the reference display brightness value based on the brightness grayscale curve corresponding to the sub-pixel in the edge display area under the reference display brightness value and the grayscale of the sub-pixel in the edge display area under the reference display brightness value.

[0097] S153: Generate the first compensation value of the sub-pixel of the edge display area in the grayscale of the reference display brightness value based on the product of the actual brightness of the sub-pixel of the edge display area in the grayscale of the reference display brightness value and the compensation coefficient corresponding to the sub-pixel of the edge display area, and the target brightness corresponding to the grayscale of the reference display brightness value.

[0098] S163: For any reference display brightness value of any sub-pixel in the edge display area, generate a reference first preset correspondence relationship corresponding to the reference display brightness value based on each gray level under the reference display brightness value and the first compensation value corresponding to each gray level.

[0099] S173: Based on the first preset correspondence of the sub-pixel to each reference display brightness value, determine the first preset correspondence of the sub-pixel to the display brightness value of the display panel. For any sub-pixel in the edge display area, determine the first compensation value corresponding to the sub-pixel in the edge display area based on the display brightness value of the display panel, the grayscale of the sub-pixel in the edge display area to the display brightness value, and the first preset correspondence of the sub-pixel in the edge display area to the display brightness value.

[0100] S183: For any grayscale of any sub-pixel in the intermediate display area at any reference display brightness value, determine the actual brightness of the sub-pixel in the intermediate display area at the grayscale of the reference display brightness value based on the corresponding brightness grayscale curve of the sub-pixel in the intermediate display area at the reference display brightness value and the grayscale at the reference display brightness value.

[0101] Once the grayscale curve corresponding to the reference display brightness value is determined, the actual brightness corresponding to any grayscale level under that reference display brightness value can be determined. For example, if the reference display brightness value is 300 nits, the actual brightness corresponding to any grayscale level of any sub-pixel under 300 nits can be determined based on the grayscale curve corresponding to any sub-pixel in the middle display area 2 at 300 nits.

[0102] S193: Generate a second compensation value based on the actual brightness of the sub-pixels in the middle display area at the grayscale of the reference display brightness value and the target brightness corresponding to the grayscale of the reference display brightness value.

[0103] Since the sub-pixels in the middle display area 2 have the same characteristics and display rules regardless of whether the display brightness value is large or small, the corresponding second compensation value is directly determined based on the actual brightness. The second preset correspondence for other display brightness values ​​determined by looking up a table or interpolation based on the second preset correspondence for the reference display brightness value also conforms to the display rules for other display brightness values, resulting in high compensation accuracy.

[0104] The feature targets any grayscale of a sub-pixel in the central display area 2 at any reference display brightness value, and determines a second compensation value based on the deviation between the actual brightness and the target brightness at that grayscale. Specifically, the magnitude of the data voltage written to the sub-pixel is continuously changed until the obtained actual brightness is the same as or has a small deviation from the target brightness. The difference between the corresponding data voltage at this point and the initial data voltage before adjustment is then determined as the second compensation value.

[0105] S203: For any reference display brightness value of any sub-pixel in any intermediate display area, generate a reference second preset correspondence relationship corresponding to the reference display brightness value based on each gray level under the reference display brightness value and the second compensation value corresponding to each gray level.

[0106] For any reference display brightness value, the corresponding second reference preset correspondence includes each gray level under the reference display brightness value and the second compensation value corresponding to each gray level.

[0107] S213: Determine the second preset correspondence of the sub-pixel under the display brightness value of the display panel according to the second preset correspondence of the sub-pixel under each reference display brightness value. For any sub-pixel in the middle display area, determine the second compensation value corresponding to the sub-pixel in the middle display area according to the display brightness value of the display panel, the grayscale of the sub-pixel in the middle display area under the display brightness value, and the second preset correspondence of the sub-pixel in the middle display area under the display brightness value.

[0108] This invention also provides a display panel that uses the brightness compensation method of the display panel in any of the above embodiments to perform brightness compensation in order to solve the problem of uneven display of the display panel, which will not be described in detail here.

[0109] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0110] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A brightness compensation method for a display panel, characterized in that, The display panel includes an edge display area and a central display area, wherein the edge display area is arranged around the central display area; The brightness compensation method for the display panel includes: For any sub-pixel in the edge display area, a first compensation value corresponding to the sub-pixel in the edge display area is determined based on the display brightness value of the display panel and the grayscale of the sub-pixel under the display brightness value. The first compensation value is related to the product of the actual brightness of the sub-pixel at the gray level under the display brightness value and the compensation coefficient corresponding to the sub-pixel. In the edge display area, the compensation coefficients corresponding to each sub-pixel arranged along the direction from the edge display area to the middle display area change monotonically. For any sub-pixel in the edge display area, the first compensation value corresponding to the same gray level under different display brightness values ​​is different.

2. The brightness compensation method for a display panel according to claim 1, characterized in that, In the edge display area, the compensation coefficients corresponding to each sub-pixel in the edge display area, arranged along the direction from the edge display area to the central display area, satisfy a linear monotonic change.

3. The brightness compensation method for a display panel according to claim 1, characterized in that, In the edge display area, the compensation coefficients corresponding to each sub-pixel in the edge display area, which are arranged along the direction from the edge display area to the middle display area, satisfy a polynomial monotonic change. Preferably, in the edge display area, the compensation coefficient corresponding to each sub-pixel in the edge display area arranged along the direction from the edge display area to the middle display area changes monotonically from 0.5 to 1, or the compensation coefficient corresponding to each sub-pixel in the edge display area arranged along the direction from the edge display area to the middle display area changes monotonically from 1.5 to 1.

4. The brightness compensation method for a display panel according to claim 1, characterized in that, For any sub-pixel in the edge display area, determining the first compensation value corresponding to the sub-pixel in the edge display area based on the display brightness value of the display panel and the grayscale of the sub-pixel in the edge display area at the display brightness value includes: For any sub-pixel in the edge display area, the first compensation value corresponding to the sub-pixel in the edge display area is determined based on the display brightness value of the display panel, the grayscale of the sub-pixel in the edge display area under the display brightness value, and the first preset correspondence relationship corresponding to the sub-pixel in the edge display area under the display brightness value; the first preset correspondence relationship is the correspondence relationship between grayscale and first compensation value. Preferably, for any sub-pixel in the edge display area, determining the first compensation value corresponding to the sub-pixel in the edge display area based on the display brightness value of the display panel, the grayscale of the sub-pixel in the edge display area at the display brightness value, and the first preset correspondence relationship corresponding to the sub-pixel in the edge display area at the display brightness value includes: The display panel includes multiple reference display brightness values ​​and a reference first preset correspondence relationship for each of the reference display brightness values; When the display brightness value of the display panel is equal to any of the reference display brightness values, the first compensation value is determined according to the reference first preset correspondence between the sub-pixels of the edge display area and the grayscale of the sub-pixels of the edge display area under the display brightness value. When the display brightness value of the display panel is not equal to any of the reference display brightness values, the first compensation value corresponding to the sub-pixel of the edge display area in the grayscale of the display brightness value is determined by interpolation calculation.

5. The brightness compensation method for a display panel according to claim 4, characterized in that, The display panel includes multiple display brightness ranges, and each display brightness range includes at least one reference display brightness value; Before determining the first compensation value corresponding to the sub-pixels of the edge display area based on the display brightness value of the display panel, the grayscale of the sub-pixels of the edge display area under the display brightness value, and the first preset correspondence relationship corresponding to the sub-pixels of the edge display area under the display brightness value, the method further includes: Obtain the brightness grayscale curve of each sub-pixel in the display panel at each of the reference display brightness values; the brightness grayscale curve is the relationship curve between grayscale and the actual brightness of the sub-pixel. For any grayscale of any sub-pixel in the edge display area at any reference display brightness value, the actual brightness of the sub-pixel in the grayscale of the reference display brightness value is determined based on the brightness grayscale curve corresponding to the sub-pixel in the edge display area at the reference display brightness value and the grayscale of the sub-pixel in the edge display area at the reference display brightness value. The first compensation value of the sub-pixel of the edge display area under the grayscale of the reference display brightness value is generated based on the product of the actual brightness of the sub-pixel of the edge display area under the grayscale of the reference display brightness value and the compensation coefficient corresponding to the sub-pixel of the edge display area, and the target brightness corresponding to the grayscale of the reference display brightness value. For any reference display brightness value of any sub-pixel in the edge display area, the reference first preset correspondence relationship corresponding to the reference display brightness value is generated based on each gray level under the reference display brightness value and the first compensation value corresponding to each gray level. Preferably, for any grayscale under any reference display brightness value, the actual brightness of the sub-pixel located at the middle position of the display panel corresponding to the grayscale under the reference display brightness value is taken as the target brightness.

6. The brightness compensation method for a display panel according to claim 5, characterized in that, Also includes: For any sub-pixel of the intermediate display area, a second compensation value corresponding to the sub-pixel of the intermediate display area at the gray level of the display brightness value is determined based on the display brightness value of the display panel, the gray level of the sub-pixel of the intermediate display area at the display brightness value, and the second preset correspondence relationship corresponding to the sub-pixel of the intermediate display area at the display brightness value. The second preset correspondence relationship is the correspondence relationship between the gray level and the second compensation value. Preferably, for any sub-pixel in the intermediate display area, the second compensation value corresponding to the same grayscale under different display brightness values ​​is different.

7. The brightness compensation method for a display panel according to claim 6, characterized in that, The step of determining the second compensation value corresponding to the grayscale of the sub-pixels in the display area at the display brightness value based on the display brightness value of the display panel, the grayscale of the sub-pixels in the middle display area at the display brightness value, and the second preset correspondence relationship corresponding to the sub-pixels in the middle display area at the display brightness value includes: When the display brightness value of the display panel is equal to any of the reference display brightness values, the second compensation value corresponding to the sub-pixels of the intermediate display area under the grayscale of the display brightness value is determined according to the reference second preset correspondence relationship corresponding to the reference display brightness value and the grayscale of the sub-pixels of the intermediate display area under the display brightness value. When the display brightness value of the display panel is not equal to any of the reference display brightness values, the second compensation value corresponding to the sub-pixel of the intermediate display area in the grayscale of the display brightness value is determined by interpolation calculation.

8. The brightness compensation method for a display panel according to claim 7, characterized in that, Before determining the second compensation value corresponding to the grayscale of the sub-pixels in the display brightness value based on the display brightness value of the display panel, the grayscale of the sub-pixels in the middle display area at the display brightness value, and the second preset correspondence relationship corresponding to the sub-pixels in the middle display area at the display brightness value, the method further includes: For any grayscale of any sub-pixel in the intermediate display area at any reference display brightness value, the actual brightness of the sub-pixel in the intermediate display area at the grayscale of the reference display brightness value is determined based on the brightness grayscale curve corresponding to the sub-pixel in the intermediate display area at the reference display brightness value and the grayscale at the reference display brightness value. A second compensation value is generated based on the actual brightness of the sub-pixels in the grayscale of the reference display brightness value and the target brightness corresponding to the grayscale of the reference display brightness value. For any reference display brightness value of any sub-pixel in any of the intermediate display areas, a reference second preset correspondence relationship is generated based on each gray level under the reference display brightness value and the second compensation value corresponding to each gray level.

9. The brightness compensation method for a display panel according to claim 5 or 8, characterized in that, Each of the aforementioned reference display brightness values ​​includes at least two bounding gray levels; Before obtaining the luminance grayscale curve of each sub-pixel corresponding to each of the reference display luminance values, the following steps are also included: For any of the aforementioned reference display brightness values, the display panel is sequentially illuminated using at least two bounding grayscale values ​​under the aforementioned reference display brightness value. Obtain the actual brightness of each of the binding point grayscales of each sub-pixel in the display panel under the reference display brightness value; For any sub-pixel, a brightness grayscale curve is generated based on the grayscale of each binding point and the actual brightness under each binding point grayscale.

10. A display panel, characterized in that, Brightness compensation is performed using the brightness compensation method for the display panel as described in any one of claims 1-9.

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