Gray scale compensation method and unit, source driver, display panel and storage medium

Abstract

The invention discloses a gray scale compensation method and unit, a source driver, a display panel and a storage medium. The method comprises the following steps: receiving pixel gray scale data of at least one frame of to-be-displayed image; the pixel gray scale data of the to-be-displayed image is divided into a plurality of first groups according to a pre-divided circulation unit, the circulation unit comprises M * N sub-pixels, M and N are both natural numbers, and at least one of M and N is larger than 1; according to the positions and pixel gray scale data of the multiple sub-pixels in at least one first group, compensation difference values corresponding to the multiple sub-pixels in the first group are determined; and compensating the pixel gray scale data of the plurality of sub-pixels in the first group according to the determined compensation difference value.

Description

Technical Field

[0001] The embodiments of the present disclosure relate to, but are not limited to, the field of display technology, and in particular to a grayscale compensation method and unit, a source driver, a display panel, and a storage medium. Background Art

[0002] With the rapid development of display technology, people's requirements for display panel image quality are becoming increasingly higher. However, under existing technical conditions, display panel products often exhibit uneven brightness when displaying images, which is known as mura in the industry. This phenomenon is particularly noticeable when the display panel displays solid colors. Summary of the Invention

[0003] The following is a summary of the subject matter described in detail herein. This summary is not intended to limit the scope of the claims.

[0004] The present disclosure provides a grayscale compensation method, including: receiving pixel grayscale data of at least one frame of image to be displayed; Dividing the pixel grayscale data of the image to be displayed into a plurality of first groups according to cyclic units pre-divided into corresponding sub-pixels, at least one of the cyclic units including M*N sub-pixels, where M and N are both natural numbers and at least one of M and N is greater than 1; The pixel grayscale data of the plurality of sub-pixels in at least one of the first groups are compensated according to the relative positions of the sub-pixels in the cycle unit and the pixel grayscale data.

[0005] An embodiment of the present disclosure further provides a grayscale compensation unit, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, the steps of the grayscale compensation method described in any embodiment of the present disclosure are implemented.

[0006] The present disclosure also provides a source driver including the grayscale compensation unit according to any one of the embodiments of the present disclosure, and further including a digital-to-analog conversion unit and a power amplification unit, wherein: The digital-to-analog conversion unit is configured to convert the pixel grayscale data output by the grayscale compensation unit into an analog data voltage signal; The power amplifying unit is configured to amplify the power of the analog data voltage signal output by the digital-to-analog conversion unit and output the amplified signal to the source driving line.

[0007] An embodiment of the present disclosure also provides a display panel having a display area and a peripheral area; wherein the display area includes multiple gate drive lines, multiple data lines, multiple sub-pixel areas defined by the intersection of the multiple gate drive lines and the multiple data lines, and a switching transistor located in the sub-pixel area, the control electrode of the switching transistor is connected to the gate drive line, and the source electrode of the switching transistor is connected to the data line; the peripheral area includes at least one source driver as described in any embodiment of the present disclosure, and the source driver is connected to the data line of the display area through a signal connection line.

[0008] An embodiment of the present disclosure further provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the steps of the grayscale compensation method as described in any embodiment of the present disclosure are implemented.

[0009] The grayscale compensation method and unit, source driver, display panel and storage medium of the embodiments of the present disclosure divide the pixel grayscale data of the image to be displayed into multiple first groups according to the cyclic units pre-divided according to the sub-pixels to which they belong, at least one cyclic unit includes M*N sub-pixels, M and N are both natural numbers, and at least one of M and N is greater than 1. According to the relative positions of the sub-pixels in the cyclic unit and the pixel grayscale data, the pixel grayscale data of multiple sub-pixels in at least one first group are compensated, which can solve the problem of brightness difference caused by the difference in the physical properties of the sub-pixels themselves, realize precise compensation drive at the sub-pixel level, and finally achieve high uniformity of display brightness of the display panel.

[0010] Other features and advantages of the present disclosure will be described in the following description, and in part will become apparent from the description, or will be understood by practicing the present disclosure. Other advantages of the present disclosure can be realized and obtained through the solutions described in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The accompanying drawings are used to provide an understanding of the technical solution of the present disclosure and constitute a part of the specification. Together with the embodiments of the present disclosure, they are used to explain the technical solution of the present disclosure and do not constitute a limitation to the technical solution of the present disclosure.

[0012] Figure 1 A schematic flow chart of a grayscale compensation method according to an exemplary embodiment of the present disclosure; Figure 2A A schematic structural diagram of a sub-pixel arrangement according to an exemplary embodiment of the present disclosure; Figure 2B for Figure 2A Schematic diagram of sub-pixel grayscale test results of a sub-pixel under a test screen (pure red screen); Figure 3A for Figure 2AA schematic diagram of the voltage charging time corresponding to the sub-pixel in an exemplary case; Figure 3B A schematic diagram of a grayscale compensation process according to an exemplary embodiment of the present disclosure; Figure 4 is a structural schematic diagram of a grayscale compensation unit according to an exemplary embodiment of the present disclosure; Figure 5 FIG. 4 is a schematic structural diagram of a source driver according to an exemplary embodiment of the present disclosure. DETAILED DESCRIPTION

[0013] In order to make the purpose, technical solutions and advantages of the present disclosure clearer, the embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. Note that the embodiments can be implemented in a variety of different forms. A person of ordinary skill in the art can easily understand the fact that the methods and contents can be transformed into various forms without departing from the purpose and scope of the present disclosure. Therefore, the present disclosure should not be interpreted as being limited to the contents described in the following embodiments. In the absence of conflict, the embodiments in the present disclosure and the features in the embodiments can be arbitrarily combined with each other.

[0014] In this specification, ordinal numbers such as “first”, “second” and “third” are provided to avoid confusion among constituent elements, and are not intended to limit the number.

[0015] Traditional display panel designs typically use a regular row-by-row display, with one source drive line connected to a column of sub-pixels. The design of each sub-pixel and its corresponding switching transistor (TFT) remains consistent. Furthermore, for conventional products such as Full High Definition (FHD) and Quad High Definition (QHD), the sub-pixels have sufficient charging time. Therefore, traditional display panels do not cause brightness differences due to sub-pixel differences or insufficient charging.

[0016] With the evolution of display technology, some special pixel connection methods have gradually emerged in the display panel field, such as dual-gate in one row, multi-gate in one row, zigzag, etc. When designing a display panel, pixel connection methods such as these will lead to design differences in sub-pixels and switching transistors or gate drive line routing in different positions, which in turn leads to slight differences in the actual aperture ratios of different sub-pixels. At this time, this difference in aperture ratio between different sub-pixels will lead to brightness differences even when there is sufficient charging time. From the perspective of the panel, since the locations where the above-mentioned sub-pixel aperture ratio differences appear show a certain regularity, vertical stripes, diagonal stripes, etc. are prone to appear when the full screen is displayed.

[0017] In addition, the ever-increasing resolution and / or refresh rate requirements of display panels have greatly compressed the sub-pixel charging time. When the charging time is tight, the subtle charging brightness differences will be further amplified, and the regular Mura problem presented on the full screen will be more prominent.

[0018] Some display panels use horizontal line overdrive (Line OD) technology for pixel grayscale compensation. This technology calculates the compensation voltage difference based on the pixel voltage difference between two adjacent rows of sub-pixels, thereby correcting the brightness difference caused by the difference in the charge state of the sub-pixels in the two adjacent rows. However, this compensation method uses pixel rows as a unit and cannot solve the brightness unevenness caused by the aforementioned sub-pixel aperture ratio differences.

[0019] like Figure 1 As shown, the embodiment of the present disclosure provides a grayscale compensation method, including: Step 101: Receive pixel grayscale data of at least one frame of image to be displayed; Step 102: Divide the pixel grayscale data of the image to be displayed into a plurality of first groups according to the cyclic units into which the sub-pixels are pre-divided, wherein at least one cyclic unit includes M*N sub-pixels, where M and N are both natural numbers, at least one of M and N is greater than 1, and * represents a multiplication sign; Step 103 : Compensate the pixel grayscale data of a plurality of sub-pixels in at least one first group according to the relative positions of the sub-pixels in the cycle unit and the pixel grayscale data.

[0020] The grayscale compensation method of the embodiment of the present disclosure divides the pixel grayscale data of the image to be displayed into multiple first groups according to the cyclic units pre-divided according to the sub-pixels to which they belong, at least one cyclic unit includes M*N sub-pixels, M and N are both natural numbers, and at least one of M and N is greater than 1. According to the relative positions of the sub-pixels in the cyclic unit and the pixel grayscale data, the pixel grayscale data of multiple sub-pixels in at least one first group are compensated, which can solve the problem of brightness difference caused by the difference in the physical properties of the sub-pixels themselves, realize precise compensation drive at the sub-pixel level, and finally achieve high uniformity of display brightness of the display panel.

[0021] In some exemplary embodiments, the circulation unit can be determined according to the arrangement rule of the sub-pixels of the display panel, and the arrangement rule of the sub-pixels includes at least one of the following: the arrangement position of the sub-pixels, the arrangement position of the gate driving lines connected to the sub-pixels, the arrangement position of the switching transistors connected to the sub-pixels, etc.

[0022] In the embodiment of the present disclosure, the arrangement rules of sub-pixels include but are not limited to the multiple arrangement position rules listed above, and may also include the arrangement rules of other elements or components in the sub-pixels, which is not limited in the present disclosure.

[0023] The following is in accordance with Figure 2A An exemplary sub-pixel arrangement rule is used for illustration, but the present disclosure is not limited thereto, and other sub-pixel arrangement rules can be derived in a similar manner.

[0024] like Figure 2A As shown, the display panel includes sub-pixels of three colors (red, green, and blue) arranged in an array, each row of sub-pixels is connected to four gate drive lines GT1 to GT4, the source drive line SR1 is respectively connected to the data lines of sub-pixels R1, R5, R7, and R3 in four columns (where RGB respectively represents the pixel grayscale data of the three color sub-pixels of the pixel, i represents the i-th pixel in the same physical row, for example, R5 represents the fifth red sub-pixel), the source drive line SG1 is respectively connected to the data lines of sub-pixels G1, G5, G7, and G3 in four columns, the source drive line SB1 is respectively connected to the data lines of sub-pixels B3, B7, B1, and B5 in four columns, the source drive line SR2 is respectively connected to the data lines of sub-pixels R4, R8, R2, and R6 in four columns, the source drive line SG2 is respectively connected to the data lines of sub-pixels G6, G2, G4, and G8 in four columns, and the source drive line SB2 is respectively connected to the data lines of sub-pixels B6, B2, B4, and B8 in four columns. The specific arrangement is shown in Table 1. By turning on the gate drive lines GT1 to GT4 four times, the source driver outputs data four times, ultimately realizing the display drive of all sub-pixels in the same physical row on the panel. Table 1 according to Figure 2A According to the arrangement pattern of the sub-pixels shown, the 24 sub-pixels R1 to R8, G1 to G8, and B1 to B8 can be set as a minimum cyclic unit (i.e., M=1, N=24). Therefore, the 24 sub-pixels R1 to R8, G1 to G8, and B1 to B8 can be divided into a first group, and the sub-pixels in other areas of the display panel can be divided into multiple first groups in this way.

[0025] In the embodiment of the present disclosure, when a plurality of gate driving lines are connected to the sub-pixels in a cycle unit, the plurality of sub-pixels in a first group may be divided into a plurality of second groups according to the gate driving lines connected to the sub-pixels.

[0026] In some exemplary embodiments, a plurality of sub-pixels in at least one first group are connected to K gate drive lines and R source drive lines, where K and R are both natural numbers greater than 1, and K*R=M*N. After dividing pixel grayscale data of an image to be displayed into the plurality of first groups according to cyclic units pre-divided into corresponding sub-pixels, the method further includes: Dividing the pixel grayscale data of the plurality of sub-pixels in the first group into K second groups according to the gate drive lines connected to the corresponding sub-pixels; The pixel grayscale data in the second group are sorted according to the arrangement order of the source driving lines connected to the corresponding sub-pixels.

[0027] See also Figure 2A , when the input image data content is R1 G1 B1 R2 G2 B2..., the pixel grayscale data of multiple sub-pixels in the first group can be divided into K (in this example, K=4) second groups according to the gate drive lines connected to the corresponding sub-pixels. For example, the sub-pixels connected to GT1 are R1, G1, B3, R4, G6, B6. Therefore, R1, G1, B3, R4, G6, B6 can be divided into the first second group. Similarly, R5, G5, B7, R8, G2, B2 are divided into the second second group, R7, G7, B1, R3, G4, B4 are divided into the third second group, and R3, G3, B5, R6, G8, B8 are divided into the fourth second group. Then, the pixel grayscale data in the second group can be sorted according to the arrangement order of the source drive lines connected to the corresponding sub-pixels. For example, Figure 2A In the example, the sub-pixels may be sorted from left to right according to the arrangement order of the source driving lines connected to the corresponding sub-pixels.

[0028] In some exemplary embodiments, compensating pixel grayscale data of a plurality of sub-pixels in at least one first group according to relative positions of the sub-pixels in the cycle unit and the pixel grayscale data includes: The following operations are performed on at least one sub-pixel in at least one first group: Determine a corresponding compensation difference lookup table based on the grayscale data of the sub-pixel, wherein one compensation difference lookup table corresponds to one grayscale or a grayscale range, and each compensation difference lookup table includes compensation differences corresponding to sub-pixels at various positions within a cyclic unit; The compensation difference value of the corresponding position in the compensation difference lookup table is obtained according to the relative position of the sub-pixel in the cyclic unit, and the pixel grayscale data of the sub-pixel is compensated using the obtained compensation difference value.

[0029] In the embodiment of the present disclosure, each compensation difference lookup table stores the compensation differences of M*N sub-pixels in a cyclic unit at a corresponding grayscale or grayscale range.

[0030] In the embodiment of the present disclosure, the compensation difference lookup table can be set to a format similar to Table 2 according to the arrangement pattern of the sub-pixels of multiple second groups within a cycle unit. After the pixel grayscale data of the image to be displayed is divided into multiple first groups according to the cycle units pre-divided by the sub-pixels to which they belong, and the pixel grayscale data of the multiple sub-pixels in the first group is divided into K second groups according to the gate drive lines connected to the corresponding sub-pixels, the pixel grayscale data in each second group can be grayscale compensated according to the compensation difference at the corresponding position of the compensation difference lookup table. Table 2 In this example, taking the sub-pixel connected to the gate drive line GT1 as an example, before the gate drive line GT1 is turned on, the source driver chip converts the input image data R1 G1 B3 R4 G6 B6 into: R1' G1' B3' R4' G6'B6' after compensation processing, and generates corresponding data voltages. When the gate drive line GT1 is turned on, the source driver chip outputs the generated data voltage to the corresponding sub-pixel through the source drive line.

[0031] In the embodiment of the present disclosure, the compensation difference lookup table can also be set to a format similar to Table 3 according to the arrangement rule of the sub-pixels of a first group in a cycle unit. After the pixel grayscale data of the image to be displayed is divided into a plurality of first groups according to the cycle units pre-divided by the sub-pixels to which they belong, the pixel grayscale data in each first group can be grayscale compensated according to the compensation difference at the corresponding position of the compensation difference lookup table. At this time, the source driver chip can compensate the pixel grayscale data of all sub-pixels in each row before driving each row of sub-pixels, and then output the data voltage corresponding to the compensated grayscale to the sub-pixels corresponding to each gate drive line in sequence when each gate drive line is turned on. Table 3 In the disclosed embodiments, a compensation difference lookup table may correspond to a grayscale or a grayscale range. For example, a compensation difference lookup table may be provided for each grayscale between 0 and 255. Alternatively, all grayscales between 0 and 255 may be divided into multiple grayscale ranges, and a compensation difference lookup table may be provided for each grayscale range. When determining the corresponding compensation difference lookup table, the table may be determined based on the grayscale or grayscale range corresponding to each compensation difference lookup table.

[0032] In some exemplary embodiments, the method further comprises: determining at least one cycle unit to be tested and a plurality of grayscales to be tested; For each grayscale to be tested, the following operations are performed: determining the luminous brightness of multiple sub-pixels in the tested cycle unit at the grayscale to be tested; determining the luminous brightness difference of sub-pixels of the same color; and generating a compensation difference lookup table based on the determined luminous brightness difference.

[0033] In the embodiment of the present disclosure, when a compensation difference lookup table is set for each gray scale, each gray scale needs to be set as the gray scale to be tested in turn, and the above-mentioned brightness difference comparison operation is performed on each gray scale to be tested. According to the determined luminous brightness difference, a compensation difference lookup table for each gray scale to be tested is generated, and the generated compensation difference lookup table is stored in the source driver.

[0034] In the embodiment of the present disclosure, the luminous brightness of multiple sub-pixels in the cycle unit to be tested at the grayscale to be tested can be obtained through simulation during the panel design stage, or through actual testing after the panel is produced. The present disclosure does not impose any restrictions on this.

[0035] When a compensation difference lookup table is set for each of multiple preset grayscale ranges, a grayscale to be measured can be selected within each preset grayscale range to perform the above-mentioned brightness difference comparison operation. Based on the determined luminous brightness difference, a compensation difference lookup table for each grayscale to be measured is generated, and the compensation difference lookup table for the grayscale to be measured is used as the compensation difference lookup table corresponding to each grayscale within the grayscale range. The generated compensation difference lookup table is stored in the source driver.

[0036] Liquid crystal molecules in liquid crystal displays (LCDs) cannot be permanently fixed at a single voltage. Otherwise, over time, even if the voltage is removed, the liquid crystal molecules' properties will be disrupted, and they will no longer be able to rotate in response to changes in the electric field to form different grayscales. Generally speaking, the display voltage in LCDs has two polarities: positive polarity and negative polarity. When the voltage of the pixel electrode is higher than the voltage of the common electrode, it is considered positive polarity; when the voltage of the pixel electrode is lower than the voltage of the common electrode, it is considered negative polarity. Regardless of whether the polarity is positive or negative, a set of grayscales with the same brightness is achieved. The electric field applied to the liquid crystal molecules is directional. If the electric field is applied to the liquid crystal in opposite directions at different times, this is called "polarity reversal." In most cases, since the distance between the two electrodes is constant, the direction of the electric field corresponds to the positive and negative potential differences. Therefore, polarity reversal also means applying positive and negative potential differences to the liquid crystal molecules.

[0037] In the disclosed embodiments, the differences in sub-pixel brightness are primarily due to the following two factors: Firstly, differences in the physical design of sub-pixels at different locations within the cyclic unit result in differences in the resulting sub-pixel brightness. Secondly, the operational amplifiers (OPs) in the source driver chip, which output positive and negative polarity voltages, have different operating voltage ranges. Consequently, when the sub-pixels are actually charged and driven, the resulting brightness of the positive and negative polarity sub-pixels can also differ slightly.

[0038] Still Figure 2A The arrangement of sub-pixels is shown in the figure. Due to the different positions of the switching transistors in the sub-pixels at different positions, the aperture ratio of the sub-pixels may be different, which ultimately leads to the brightness difference of the sub-pixel level. Taking the L127 grayscale data of the full red screen as an example, in an ideal situation, the brightness of all red sub-pixels is 127, and the brightness of blue and green sub-pixels is 0. However, the actual brightness of the red sub-pixels is as follows: Figure 2B It should be noted that Figure 2B The brightness in is just one example.

[0039] See also Figure 2B When the gate drive line GT1 is turned on, the driven red sub-pixels are R1 and R4, R1 is + polarity, the brightness is 127, R4 is - polarity, the brightness is 126.8; when the gate drive line GT2 is turned on, the driven red sub-pixels are R5 and R8, R5 is + polarity, the brightness is 126.5, R8 is - polarity, the brightness is 126.3; when the gate drive line GT3 is turned on, the driven red sub-pixels are R7 and R2, R7 is + polarity, the brightness is 127.4, R2 is - polarity, the brightness is 127.2; when the gate drive line GT4 is turned on, the driven red sub-pixels are R3 and R6, R3 is + polarity, the brightness is 127, R6 is - polarity, the brightness is 126.8.

[0040] It can be seen that the brightness differences caused by different factors are: 1) The brightness of the -polarity sub-pixel when driven is about 0.2 lower than the brightness of the +polarity sub-pixel when driven. Grayscale compensation needs to be performed on all negative OP (i.e., OP that outputs negative polarity voltage) driven sub-pixels, and the compensation difference is 0.2; 2) The brightness of the gate drive line GT1 and the gate drive line GT4 are basically the same, both with a basic brightness of 127, but when the gate drive line GT2 and the gate drive line GT3 are driven, the position of the switching transistor affects the aperture ratio, resulting in slight differences in brightness. Among them, the brightness of the sub-pixel driven by the gate drive line GT2 is reduced by 0.5, and the brightness of the sub-pixel driven by the gate drive line GT3 is increased by 0.4. Accordingly, when driven by different gate drive lines, grayscale compensation is performed on the corresponding sub-pixels.

[0041] The embodiment of the present disclosure uses a compensation difference lookup table to store the brightness difference compensation value caused by the physical design of the sub-pixel. Since the compensation value may be different at different grayscales, the compensation difference lookup table can store the compensation value at different grayscales. Since the pixel design is repeated in a cyclic unit, the difference compensation of different sub-pixels can be stored according to the minimum cyclic unit. For example Figure 2A In the exemplary pixel arrangement, 24 sub-pixels are used as a period, and 6 source drive lines and 4 gate drive lines are used in conjunction with each other. The corresponding compensation difference lookup table stores the compensation values ​​corresponding to the 24 sub-pixels in one period.

[0042] like Figure 2A As shown, the gate drive lines GT1 to GT4 are OP driven four times in succession, that is, the chip is processed as four sets of data in sequence. Before each OP drive or before driving a row of pixels, the corresponding compensation value is called for compensation.

[0043] In some exemplary embodiments, the method further comprises: The waiting frame number is determined according to the compensation difference values ​​corresponding to the plurality of sub-pixels in the first group, where the waiting frame number is the number of image frames to be displayed without compensation after the current compensation.

[0044] Referring to the aforementioned actual brightness difference values, the brightness differences are generally small (less than 1). If voltage compensation is performed through ±1 grayscale, over-compensation or under-compensation will be formed. Therefore, the embodiment of the present disclosure can set some waiting frame intervals after one compensation, and no grayscale compensation is performed during the waiting frame interval. By superimposing multiple frames, a finer compensation adjustment accuracy can be obtained. For example, if the pixel grayscale of a red sub-pixel in the first frame performs +1 compensation, and the pixel grayscale of the red sub-pixel in the second to fourth frames is not compensated, then a total of 4 frames of 127+1, 127+0, 127+0, and 127+0 are combined (that is, the number of waiting frames is 3), and a compensation effect of +0.25 for the red sub-pixel can be obtained. Similarly, by superimposing more frames, a finer compensation adjustment accuracy can be obtained.

[0045] In some other exemplary embodiments, the method further comprises: Determine whether pixel grayscale data of multiple consecutive frames of images to be displayed are the same; When the pixel grayscale data of multiple consecutive frames of images to be displayed are the same, the waiting frame number is determined according to the compensation differences corresponding to multiple sub-pixels in the first group. The waiting frame number is the number of frames of the image to be displayed without compensation after the current compensation.

[0046] In the embodiment of the present disclosure, when determining the number of waiting frames, it is also possible to first determine whether the pixel grayscale data of multiple consecutive frames of images to be displayed are the same. When the pixel grayscale data of multiple consecutive frames of images to be displayed are the same, the next compensation is performed after setting the interval time of one or more waiting frames according to the aforementioned method; when the pixel grayscale data of multiple consecutive frames of images to be displayed are different, the interval time of the waiting frames may not be set, and the pixel grayscale data of each frame of the image to be displayed may be directly compensated according to the aforementioned compensation method, or no compensation may be performed (when the image content is constantly changing, the subtle brightness differences caused by the differences in sub-pixel aperture ratios are not easy to be observed by people).

[0047] The timing controller (TCON) chip can achieve finer compensation adjustment accuracy through dithering. However, the TCON chip usually implements dithering when converting high-bit data into low-bit data after internal image processing is completed. The dithering operation is relatively complex, involving 4*4, 8*8, 16*16 and other equalization operations. This method has a large area cost and requires a lot of cached data, making it unsuitable for implementation in the display driver chip.

[0048] The grayscale compensation method of the disclosed embodiment can be implemented through frame counting, a multiplexer (MUX), and an adder, and can be implemented within a display driver chip. The display driver chip can implement frame counting based on the time-domain control signal received from the front end. The driver chip only needs to select frames through the multiplexer and perform simple accumulation calculations through the adder, such as simple parameter information processing such as "this frame + 1" and "this frame + 0," to achieve sub-pixel brightness compensation.

[0049] In some exemplary embodiments, before compensating the pixel grayscale data of the plurality of sub-pixels in the at least one first group, the method further includes: determining whether pixel grayscale data of a plurality of sub-pixels in the first group is within a preset threshold range; When the pixel grayscale data of one or more sub-pixels is outside a preset threshold range, determining the corresponding compensation difference value of the one or more sub-pixels to be 0; When the pixel grayscale data of one or more sub-pixels is within a preset threshold range, the aforementioned step of compensating the pixel grayscale data of multiple sub-pixels in at least one first group according to the relative positions and pixel grayscale data of the sub-pixels in the cycle unit is triggered.

[0050] For some special pictures, such as when the original grayscale is 0, for example, in the above detection process, taking a pure red picture as an example, the grayscale of the red sub-pixel is 127, and the grayscales of the green sub-pixels and the blue sub-pixels are both 0. In order to avoid the green sub-pixels and the blue sub-pixels being displayed on the basis of grayscale 0 due to the above compensation operation, affecting the contrast, a special threshold judgment can be performed before compensation. If the pixel grayscale data of one or more sub-pixels is outside the preset threshold range, it will not be compensated. In this way, for special pictures such as low grayscale and high grayscale, sub-pixel brightness compensation is not performed. Since the above brightness compensation is all based on the judgment of sub-pixel grayscale data, it does not involve complex pictures or working mode detection, and the cost of implementation in the display driver chip is low, and the cost required is low.

[0051] In the embodiment of the present disclosure, the preset threshold range can be set as needed, and the present disclosure does not limit this.

[0052] In summary, after the above compensation operation, the original R / G / B grayscale data is compensated to obtain R' G' B' data during multiple gate drive line drive outputs and multi-frame outputs, thereby achieving grayscale compensation at the sub-pixel level. At the same time, because the above compensation operation is designed based on the minimum cyclic unit of panel pixel design differences, the internal operation logic, compensation difference lookup table and other compensation information storage are all minimum units, which will not increase the burden on the display driver chip.

[0053] In some exemplary embodiments, the method further comprises: Obtaining polarities of voltage signals of a plurality of sub-pixels in a first group; The voltage charging time is determined according to the polarities of the voltage signals of the plurality of sub-pixels in the first group, and the voltage charging time of the sub-pixels with negative voltage signal polarity is longer than the voltage charging time of the sub-pixels with positive voltage signal polarity.

[0054] The grayscale compensation method of the embodiment of the present disclosure can also perform differentiated control on the voltage output time of the operational amplifier based on the grayscale compensation of the previous level pixel (i.e., driving voltage compensation), thereby ensuring that the brightness performance of the sub-pixels after charging is ultimately consistent.

[0055] Still with the above Figure 2BTaking an exemplary embodiment as an example, the brightness of a negative-polarity sub-pixel when driven is approximately 0.2 lower than that of a positive-polarity sub-pixel when driven. This increases the voltage charging time of all negative-OP-driven sub-pixels, while reducing or not increasing the voltage charging time of all positive-OP-driven sub-pixels. A negative OP refers to an OP that outputs a negative voltage, and a positive OP refers to an OP that outputs a positive voltage. This embodiment controls the output time of the operational amplifier to adjust the charging time of the driving voltage ultimately applied to the source drive line and the sub-pixel.

[0056] In some exemplary embodiments, the method further comprises: Obtaining arrangement positions of gate drive lines connected to a plurality of sub-pixels in the second group; The voltage charging time of the multiple sub-pixels in the second group is determined according to the arrangement positions of the gate drive lines connected to the multiple sub-pixels in the second group, and the voltage charging time corresponding to each gate drive line is determined according to the brightness average value of the sub-pixels connected to the gate drive line detected in advance.

[0057] In the embodiment of the present disclosure, refer to the above Figure 2A The pixel driving sequence, gate drive line GT2 and gate drive line GT3 have slightly different aperture ratios due to the different positions of the switching transistors. From the perspective of driving timing, the gate drive line GT1 to gate drive line GT4 are kept unchanged in each row (because the compensation processing is all done on the driver chip side, the front-end control of the shift register GOA (or gate drive circuit) remains unchanged). When each row of gate drive lines is turned on, it matches a different operational amplifier turn-on timing. For example, Figure 3A As shown, the operational amplifier turn-on timing corresponding to the gate drive line GT1 and the gate drive line GT4 is used as the basic timing, and the operational amplifier turn-on time corresponding to the gate drive line GT1 and the gate drive line GT4 is set to T; the gate drive line GT2 drives the sub-pixel brightness to be low, and the operational amplifier turn-on time corresponding to the gate drive line GT2 is adjusted to T+Δt1, where Δt1 is a positive value, thereby extending the effective charging time; the gate drive line GT3 drives the sub-pixel brightness to be high, and the operational amplifier turn-on time corresponding to the gate drive line GT3 is adjusted to T+Δt2, where Δt2 is a negative value, thereby shortening the effective charging time.

[0058] The above adjustment of the voltage charging time is also based on the minimum cycle unit of pixel design, for example Figure 2A In the embodiment, the sub-pixels connected by 4 gate lines are a cycle unit, and the timing adjustment is also adjusted with 4-row driving time as a cycle unit, which can be expanded according to the difference in pixel design.

[0059] In some exemplary embodiments, the method further comprises: Obtaining an average distance between a plurality of sub-pixels in the first group and the source driver chip; The voltage charging time is determined according to the average distance between the multiple sub-pixels in the first group and the source driver chip. The voltage charging time of the first group in which the average distance between the multiple sub-pixels and the source driver chip is short is shorter than the voltage charging time of the first group in which the average distance between the multiple sub-pixels and the source driver chip is long.

[0060] Generally speaking, sub-pixels closer to the source driver chip have better charging effects than sub-pixels farther from the source driver chip. Therefore, the voltage charging time of sub-pixels farther from the source driver chip can be increased, while the voltage charging time of sub-pixels closer to the source driver chip can be reduced or not increased.

[0061] In other examples, the voltage charging time of sub-pixels at different positions of the panel can also be determined based on the non-uniformity of the panel production process. For example, the uniformity of sub-pixels at the middle position of the panel is generally better than the uniformity of sub-pixels at the edge position of the panel. Therefore, the voltage charging time of sub-pixels at the edge position of the panel can be increased, and the voltage charging time of sub-pixels at the middle position of the panel can be reduced or not increased.

[0062] For example, Figure 3B As shown, in an exemplary embodiment, when using the grayscale compensation method of the present disclosure, sub-pixel data mapping is first performed on the received pixel grayscale data of the image frame to be displayed, so as to rearrange the original RGB image data and match the connection relationship between the source drive and gate drive of different pixel panels. This step can be omitted when a row of sub-pixels in the display panel is connected to a corresponding gate drive line.

[0063] Next, by matching the corresponding compensation difference in the compensation difference lookup table, the sub-pixel grayscale data in each cycle is compensated for level I. In this step, a finer compensation adjustment accuracy can be achieved by waiting for the frame count, and the threshold range is used to determine whether the special picture compensation affects the contrast.

[0064] Next, based on the aforementioned Level I compensation process, Level II compensation is achieved by differentially controlling the OP output timing. The grayscale compensation method of the disclosed embodiment can ensure that the brightness of each sub-pixel after charging is consistent, achieving precise compensation drive at the sub-pixel level, and ultimately achieving highly uniform display brightness across the display panel.

[0065] An embodiment of the present disclosure further provides a grayscale compensation unit, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the steps of the grayscale compensation method as described in any embodiment of the present disclosure are implemented.

[0066] like Figure 4 As shown, in one example, the grayscale compensation unit may include: a processor 410, a memory 420, a bus system 430, and a transceiver 440, wherein the processor 410, the memory 420, and the transceiver 440 are connected via the bus system 430, the memory 420 is used to store instructions, and the processor 410 is used to execute the instructions stored in the memory 420 to control the transceiver 440 to send and receive signals. Specifically, under the control of the processor 410, the transceiver 440 may receive pixel grayscale data of at least one frame of an image to be displayed, and the processor 410 divides the pixel grayscale data of the image to be displayed into a plurality of first groups according to cyclic units pre-divided into sub-pixels, at least one of the cyclic units includes M*N sub-pixels, where M and N are both natural numbers, and at least one of M and N is greater than 1; and the pixel grayscale data of a plurality of sub-pixels in at least one of the first groups is compensated according to the relative positions of the sub-pixels in the cyclic unit and the pixel grayscale data.

[0067] It should be understood that the processor 410 may be a central processing unit (CPU), or may be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or any conventional processor.

[0068] The memory 420 may include a read-only memory and a random access memory, and provides instructions and data to the processor 410. A portion of the memory 420 may also include a non-volatile random access memory. For example, the memory 420 may also store information about the device type.

[0069] In addition to the data bus, the bus system 430 may also include a power bus, a control bus, and a status signal bus. Figure 4 Various buses are labeled as bus system 430 .

[0070] During implementation, the processing performed by the processing device can be completed by the hardware integrated logic circuit in the processor 410 or by instructions in the form of software. That is, the method steps of the embodiment of the present disclosure can be embodied as being executed by a hardware processor, or by a combination of hardware and software modules in the processor. The software module can be located in a storage medium such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory, or an electrically erasable programmable memory, a register, etc. The storage medium is located in the memory 420, and the processor 410 reads the information in the memory 420 and completes the steps of the above method in combination with its hardware. To avoid repetition, it will not be described in detail here.

[0071] like Figure 5 As shown, an embodiment of the present disclosure further provides a source driver, which includes the grayscale compensation unit 501 as described in any embodiment of the present disclosure, and also includes a digital-to-analog conversion unit 502 and a power amplification unit 503, wherein: The grayscale compensation unit 501 is configured to compensate the pixel grayscale data of at least one frame of the image to be displayed according to the above method; The digital-to-analog conversion unit 502 is configured to convert the pixel grayscale data output by the grayscale compensation unit 501 into an analog data voltage signal; The power amplifying unit 503 is configured to amplify the power of the analog data voltage signal output by the digital-to-analog converting unit 502 and output the amplified signal to the source driving line.

[0072] In the embodiment of the present disclosure, the digital-to-analog conversion unit 502 may be implemented by a digital-to-analog converter.

[0073] In the embodiment of the present disclosure, the power amplification unit 503 can be implemented by the operational amplifier (OP) described in the above embodiment. In the above embodiment, the adjustment of the sub-pixel voltage charging time can be achieved by controlling the turn-on time of the operational amplifier.

[0074] In some exemplary embodiments, the grayscale compensation unit 501 is further configured to output a first control signal to the power amplification unit 503 according to the determined voltage charging time, and the first control signal is used to control the duration of the power amplification unit 503 outputting the analog data voltage signal to the source driving line.

[0075] In this embodiment, how the grayscale compensation unit 501 specifically compensates the pixel grayscale data of a frame of image to be displayed can be found in the description of the above embodiment, which will not be repeated here.

[0076] The embodiment of the present disclosure further provides a display panel having a display area and a peripheral area; wherein, The display area includes a plurality of gate drive lines, a plurality of data lines, a plurality of sub-pixel regions defined by the intersection of the plurality of gate drive lines and the plurality of data lines, and a switching transistor located in the sub-pixel region, wherein the control electrode of the switching transistor is connected to the gate drive line, and the source electrode of the switching transistor is connected to the data line; The peripheral area includes at least one source driver as described in any embodiment of the present disclosure, and the source driver is connected to the data line of the display area through a source driving line.

[0077] An embodiment of the present disclosure further provides a display device, which includes: a display panel as described in any embodiment of the present disclosure.

[0078] In an exemplary embodiment, the display device may be any product or component with a display function, such as a wearable device, a mobile phone, a tablet computer, a television, a monitor, a laptop computer, a digital photo frame, or a navigator.

[0079] The drawings of the embodiments of the present disclosure only involve the structures involved in the embodiments of the present disclosure, and other structures may refer to general designs.

[0080] For the sake of clarity, the thickness and size of layers or microstructures are exaggerated in the drawings used to describe the embodiments of the present disclosure. It will be understood that when an element such as a layer, film, region, or substrate is referred to as being "on" or "under" another element, the element can be "directly on" or "under" the other element, or intervening elements may be present.

[0081] Although the embodiments disclosed in this disclosure are as described above, the contents described are merely embodiments adopted to facilitate understanding of the disclosure and are not intended to limit the disclosure. Any person skilled in the art to which the disclosure belongs may make any modifications and changes in the form and details of the implementation without departing from the spirit and scope of the disclosure. However, the scope of patent protection of the disclosure shall still be based on the scope defined by the attached claims.

Claims

1. A grayscale compensation method, characterized in that: include: receiving pixel grayscale data of at least one frame of image to be displayed; Dividing the pixel grayscale data of the image to be displayed into a plurality of first groups according to cyclic units pre-divided into corresponding sub-pixels, wherein at least one of the cyclic units includes M*N sub-pixels, where M and N are both natural numbers, at least one of M and N is greater than 1, and * represents a multiplication sign; The pixel grayscale data of the plurality of sub-pixels in at least one of the first groups are compensated according to the relative positions of the sub-pixels in the cycle unit and the pixel grayscale data.

2. The method according to claim 1, characterized in that The compensating pixel grayscale data of a plurality of sub-pixels in at least one of the first groups according to the relative positions of the sub-pixels in the cycle unit and the pixel grayscale data includes: Perform the following operation on at least one sub-pixel in at least one of the first groups: Determine a corresponding compensation difference lookup table according to the pixel grayscale data of the sub-pixel, wherein one compensation difference lookup table corresponds to one grayscale or a grayscale range, and each compensation difference lookup table includes compensation differences corresponding to sub-pixels at various positions within a cyclic unit; The compensation difference value of the corresponding position of the compensation difference lookup table is obtained according to the relative position of the sub-pixel in the circulation unit, and the pixel grayscale data of the sub-pixel is compensated using the obtained compensation difference value.

3. The method according to claim 2, characterized in that The method also includes: determining at least one cycle unit to be tested and a plurality of grayscales to be tested; For each grayscale to be tested, the following operations are performed: determining the luminous brightness of multiple sub-pixels in the cycle unit to be tested at the grayscale to be tested; determining the luminous brightness difference of sub-pixels of the same color; and generating the compensation difference lookup table according to the determined luminous brightness difference.

4. The method according to claim 2, characterized in that The method further comprises: The waiting frame number is determined according to the compensation difference values ​​corresponding to the plurality of sub-pixels in the first group, where the waiting frame number is the number of image frames to be displayed without compensation after the current compensation.

5. The method according to claim 2, characterized in that The method further comprises: Determine whether pixel grayscale data of multiple consecutive frames of images to be displayed are the same; When the pixel grayscale data of multiple consecutive frames of images to be displayed are the same, the waiting frame number is determined according to the compensation difference values ​​corresponding to the multiple sub-pixels in the first group. The waiting frame number is the number of image frames to be displayed without compensation after the current compensation.

6. The method according to claim 2, characterized in that Before compensating the pixel grayscale data of the plurality of sub-pixels in at least one of the first groups, the method further includes: determining whether pixel grayscale data of a plurality of sub-pixels in the first group is within a preset threshold range; When the pixel grayscale data of one or more sub-pixels is outside a preset threshold range, the corresponding compensation difference values ​​of the one or more sub-pixels are determined to be 0.

7. The method according to claim 1, characterized in that The circulation unit is determined according to the arrangement rule of the sub-pixels of the display panel, and the arrangement rule of the sub-pixels includes at least one of the following: the arrangement position of the sub-pixels, the arrangement position of the gate driving lines connected to the sub-pixels, and the arrangement position of the switching transistors connected to the sub-pixels.

8. The method according to claim 1, characterized in that A plurality of sub-pixels in at least one of the first groups are connected to K gate drive lines and R source drive lines, where K and R are both natural numbers greater than 1, and K*R=M*N. After dividing the pixel grayscale data of the image to be displayed into a plurality of first groups according to the cyclic units pre-divided into which the sub-pixels belong, the method further includes: Dividing the pixel grayscale data of the plurality of sub-pixels in the first group into K second groups according to the gate drive lines connected to the corresponding sub-pixels; The pixel grayscale data in the second group are sorted according to the arrangement order of the source driving lines connected to the corresponding sub-pixels.

9. The method according to claim 8, characterized in that The method further comprises: Obtaining arrangement positions of gate drive lines connected to a plurality of sub-pixels of the second group; The voltage charging time of the multiple sub-pixels in the second group is determined according to the arrangement positions of the gate drive lines connected to the multiple sub-pixels in the second group, and the voltage charging time corresponding to each of the gate drive lines is determined according to the pre-detected average brightness of the sub-pixels connected to the gate drive line.

10. The method according to claim 1, characterized in that The method further comprises: Obtaining an average distance between a plurality of sub-pixels in the first group and a source driver chip; The voltage charging time is determined based on the average distance between the multiple sub-pixels in the first group and the source driver chip, and the voltage charging time of the first group in which the average distance between the multiple sub-pixels and the source driver chip is longer is longer than the voltage charging time of the first group in which the average distance between the multiple sub-pixels and the source driver chip is shorter.

11. The method according to claim 1, wherein The method further comprises: determining polarities of voltage signals of a plurality of sub-pixels in the first group; The voltage charging time is determined according to the polarities of the voltage signals of the plurality of sub-pixels in the first group, wherein the voltage charging time of the sub-pixels with negative voltage signal polarity is longer than the voltage charging time of the sub-pixels with positive voltage signal polarity.

12. A grayscale compensation unit, characterized in that: The method comprises a memory, a processor and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the steps of the grayscale compensation method according to any one of claims 1 to 11 are implemented.

13. A source driver, characterized in that: The grayscale compensation unit according to claim 12 further comprises a digital-to-analog conversion unit and a power amplification unit, wherein: The digital-to-analog conversion unit is configured to convert the pixel grayscale data output by the grayscale compensation unit into an analog data voltage signal; The power amplifying unit is configured to amplify the power of the analog data voltage signal output by the digital-to-analog conversion unit and output the amplified signal to the source driving line.

14. A display panel, characterized in that: It has a display area and a peripheral area; wherein, The display area includes a plurality of gate drive lines, a plurality of data lines, a plurality of sub-pixel areas defined by the intersection of the plurality of gate drive lines and the plurality of data lines, and a switching transistor located in the sub-pixel area, wherein the control electrode of the switching transistor is connected to the gate drive line, and the source electrode of the switching transistor is connected to the data line; The peripheral area includes at least one source driver as claimed in claim 13 , and the source driver is connected to the data lines of the display area through source driving lines.

15. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the grayscale compensation method according to any one of claims 1 to 11 are implemented.

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