Driving method of display panel, display panel and driving circuit thereof

Abstract

This application discloses a driving method for a display panel, a display panel, and a driving circuit thereof. The driving method includes the following steps: calculating the difference between the grayscale value of the data voltage of the positive channel and the grayscale value of the data voltage of the negative channel; when the difference is less than a grayscale difference threshold, using a standard preset level to control the driving level of the positive channel and the driving level of the negative channel respectively; when the difference is greater than or equal to the grayscale difference threshold, using a first preset level to control the driving level of the positive channel and the driving level of the negative channel respectively; the first preset level is greater than or less than a standard preset level, and the larger the driving level, the faster the data voltage of the positive channel or the data voltage of the negative channel reaches the target potential. This application makes the feedthrough voltage of two grayscale levels with large differences nearly identical, so that they are nearly identical when setting the optimal common voltage, thereby improving the ghosting phenomenon caused by two grayscale levels with large differences.

Description

Technical Field

[0001] This application relates to the field of display technology, and in particular to a driving method for a display panel, a display panel and its driving circuit. Background Technology

[0002] In LCD display panels, to prevent the liquid crystal molecules from polarizing under the same voltage for an extended period when displaying static images, positive and negative driving voltages are introduced. Theoretically, these voltages correspond in meaning, and the absolute values ​​of the voltages applied to both sides of the liquid crystal molecules are equal. However, due to parasitic capacitances, such as the coupling effect between the gate voltage of the thin-film transistor (TFT) and the liquid crystal capacitor Clc and storage capacitor Cst, the voltage of the pixel electrode drops. This drop in voltage is called the feedthrough voltage, which causes a level shift in the optimal common voltage Vcom. The difference in feedthrough voltage prevents the effective voltage between the pixel electrode and the common voltage Vcom from being fully reset, resulting in a DC voltage bias across frames. This bias continues to act on the liquid crystal molecules, changing their alignment, causing residual images to be "imprinted" onto the screen, resulting in image retention, or ghosting. In the exemplary technology, the image retention phenomenon is suppressed by modifying the gray level reference voltage of a specific gray level, such as gray level 0. However, this method cannot take into account the situation of each gray level, and the image retention phenomenon will still exist when there are other gray level changes. Summary of the Invention

[0003] The purpose of this application is to provide a driving method for a display panel, a display panel and its driving circuit, so that the feedthrough voltages of two gray levels with large differences are nearly identical, so that they are nearly identical when the optimal common voltage is set, thereby improving the image retention phenomenon caused by two gray levels with large differences.

[0004] This application discloses a method for driving a display panel, including the following steps: Obtain the data voltage of one positive polarity channel and one negative polarity channel in the current frame; Calculate the difference between the grayscale value of the data voltage of the positive polarity channel and the grayscale value of the data voltage of the negative polarity channel; The absolute value of the difference is compared with the grayscale difference threshold, and the driving level of the positive polarity channel and the driving level of the negative polarity channel are controlled according to the comparison result. Wherein, when the difference is less than the gray level difference threshold, the driving level of the positive polarity channel and the driving level of the negative polarity channel are controlled by a standard preset level respectively. When the difference is greater than or equal to the grayscale difference threshold, the driving level of the positive polarity channel and the driving level of the negative polarity channel are controlled by the first preset level respectively. Wherein, the first preset gear is greater than or less than the standard preset gear, and the larger the driving gear, the faster the data voltage of the positive polarity channel or the data voltage of the negative polarity channel reaches the target potential.

[0005] Optionally, the step of calculating the difference between the grayscale value of the data voltage of the positive polarity channel and the grayscale value of the data voltage of the negative polarity channel includes: When the grayscale value of the data voltage of the positive polarity channel is greater than the grayscale value of the data voltage of the negative polarity channel, the difference between the grayscale value of the data voltage of the positive polarity channel and the grayscale value of the data voltage of the negative polarity channel is calculated as the first difference value. The step of controlling the driving level of the positive channel and the driving level of the negative channel respectively using a first preset level when the difference is greater than or equal to the gray level difference threshold includes: When the first difference is greater than or equal to the grayscale difference threshold, one or n gears are added on the basis of the standard preset gears as driving gears for controlling the positive polarity channel and driving gears for the negative polarity channel. Where n is a natural number greater than 1.

[0006] Optionally, the step of calculating the difference between the grayscale value of the data voltage of the positive polarity channel and the grayscale value of the data voltage of the negative polarity channel includes: When the grayscale value of the data voltage of the positive polarity channel is less than the grayscale value of the data voltage of the negative polarity channel, the difference between the grayscale value of the data voltage of the positive polarity channel and the grayscale value of the data voltage of the negative polarity channel is calculated as the second difference value. The step of controlling the driving level of the positive channel and the driving level of the negative channel respectively using a first preset level when the difference is greater than or equal to the gray level difference threshold includes: When the second difference is greater than or equal to the grayscale difference threshold, one or n levels are reduced from the standard preset levels as the driving levels for controlling the positive polarity channel and the negative polarity channel. Where n is a natural number greater than 1.

[0007] Optionally, the greater the difference between the difference and the grayscale difference threshold, the greater the level difference between the first preset level and the standard preset level.

[0008] Optionally, the display panel further includes a grayscale mapping table, in which grayscale values ​​of all the data signals are set. The grayscale mapping table includes x sequentially increasing grayscale values, where x is an even number greater than 0, the minimum grayscale value is 0, the maximum grayscale value is x-1, and the grayscale difference threshold is equal to x / 2.

[0009] Optionally, the grayscale mapping table includes 256 sequentially increasing grayscale values, and the grayscale difference threshold is 128. When the difference is greater than 128 and less than 144, the first preset level is increased or decreased by one level based on the standard preset level; when the difference is greater than 144 and less than 176, the first preset level is increased or decreased by two levels based on the standard preset level; when the difference is greater than 176 and less than 208, the first preset level is increased or decreased by three levels based on the standard preset level; when the difference is greater than 208 and less than 240, the first preset level is increased or decreased by four levels based on the standard preset level; when the difference is greater than 240 and less than 255, the first preset level is increased or decreased by five levels based on the standard preset level.

[0010] Optionally, after comparing the absolute value of the difference with the grayscale difference threshold and controlling the driving level of the positive polarity channel and the driving level of the negative polarity channel based on the comparison result, the method further includes: Acquire the data voltage of one positive polarity channel and one negative polarity channel across multiple consecutive frames; When the grayscale value of the data voltage of the positive polarity channel in the previous frame is greater than the grayscale value of the data voltage of the negative polarity channel, the difference between the grayscale value of the data voltage of the positive polarity channel and the grayscale value of the data voltage of the negative polarity channel is calculated as the first difference. When the first difference is greater than or equal to the grayscale difference threshold, one or more gears are added on the basis of the standard preset gears as driving gears for controlling the positive polarity channel and driving gears for the negative polarity channel. When the grayscale value of the data voltage of the positive polarity channel in the next frame is less than the grayscale value of the data voltage of the negative polarity channel, the difference between the grayscale value of the data voltage of the positive polarity channel and the grayscale value of the data voltage of the negative polarity channel is calculated as the second difference value. When the second difference is greater than or equal to the grayscale difference threshold, the driving gear of the positive polarity channel and the driving gear of the negative polarity channel are controlled by the standard preset gear.

[0011] Optionally, the step of obtaining the data voltage of one positive polarity channel and one negative polarity channel of the current frame includes, before: Obtain the data voltage of a preset region for a consecutive preset number of frames; If the data voltage in the preset area does not change for a preset number of consecutive frames, it is determined to be a static image; after the preset number of frames, the control data line is connected to the common electrode line to discharge; If there is a change in the data voltage in the preset area for a consecutive preset number of frames, it is determined that the screen has switched from a static screen to a dynamic screen, and the steps of obtaining the data voltage of one positive polarity channel and one negative polarity channel of the current frame are performed.

[0012] This application also discloses a driving circuit for a display panel, characterized in that it employs the aforementioned driving method for the display panel, wherein the driving circuit includes a timing controller, a calculation circuit, and a data driving circuit; the timing controller is used to acquire the data voltage of a positive polarity channel and the data voltage of a negative polarity channel in the current frame; the calculation circuit is used to calculate the difference between the grayscale value of the data voltage of the positive polarity channel and the grayscale value of the data voltage of the negative polarity channel, and compare the absolute value of the difference with a grayscale difference threshold; the data driving circuit includes at least one positive polarity channel and one negative polarity channel, wherein one of the positive polarity channels... A positive channel and a negative channel are each connected to a data line; wherein, when the difference is less than the grayscale difference threshold, the timing controller uses a standard preset level to control the driving level of the positive channel and the driving level of the negative channel respectively; when the difference is greater than or equal to the grayscale difference threshold, the timing controller uses a first preset level to control the driving level of the positive channel and the driving level of the negative channel respectively; wherein, the first preset level is greater than or less than the standard preset level, and the larger the driving level, the faster the data voltage of the positive channel or the data voltage of the negative channel reaches the target potential.

[0013] This application also discloses a display device, which includes a display panel and a driving circuit, wherein the driving circuit is the aforementioned driving circuit, and the driving circuit is used to drive the display panel to display.

[0014] This application monitors one positive and one negative channel of the current frame. When the difference between the grayscale values ​​of the positive and negative data voltages exceeds a grayscale difference threshold, it indicates that image retention will occur when switching to other grayscale levels, requiring compensation for the data voltages of these two channels. By adjusting the drive levels of the positive and negative channels containing the two data voltages, the feedthrough voltages of the two significantly different data voltages are brought closer together, thereby bringing the feedthrough voltages of the two significantly different grayscale levels closer together. This ensures that the optimal common voltage is set almost identically, thus improving the image retention phenomenon caused by the significant difference in grayscale levels. Attached Figure Description

[0015] The accompanying drawings, which form part of the specification, are used to provide a further understanding of the embodiments of this application and illustrate the implementation methods of this application, together with the textual description, to explain the principles of this application. Obviously, the drawings described below are merely some embodiments of this application, and those skilled in the art can obtain other drawings based on these drawings without any creative effort. In the drawings: Figure 1 This is a schematic diagram illustrating the steps of a driving method for a display panel according to this application; Figure 2 This is a schematic diagram of grayscale voltage and feedthrough voltage according to an embodiment of this application; Figure 3 This is a schematic diagram of the steps of the second type of display panel driving method of this application; Figure 4 This is a schematic diagram of the driving circuit of the display panel of this application; Figure 5 This is a schematic diagram of the computing circuit of this application; Figure 6 This is a schematic diagram of the steps of the third display panel driving method of this application; Figure 7 This is a schematic diagram of the display panel of this application.

[0016] Among them, 100 is a driving circuit; 110 is a timing controller; 120 is a calculation circuit; 121 is a subtractor; 121a is a first input terminal; 121b is a second input terminal; 122 is a comparator; 122a is a first comparison input terminal; 122b is a second comparison input terminal; 130 is a data driving circuit; 131 is a positive polarity channel; 132 is a negative polarity channel; 200 is a display panel; and 300 is a display device. Detailed Implementation

[0017] It should be understood that the terminology, specific structural and functional details used herein are merely for describing particular embodiments and are representative. However, this application may be implemented in many alternative forms and should not be construed as being limited to the embodiments set forth herein.

[0018] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating relative importance or implying the number of technical features indicated. Therefore, unless otherwise stated, a feature specified as "first" or "second" may explicitly or implicitly include one or more of that feature; "multiple" means two or more. Furthermore, terms such as "upper," "lower," "left," "right," "vertical," and "horizontal," indicating orientation or positional relationships, are based on the orientation or relative positional relationships shown in the accompanying drawings and are only for the purpose of simplifying the description of this application, not indicating that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as limiting this application. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0019] The present application will now be described in detail with reference to the accompanying drawings and optional embodiments.

[0020] Figure 1 This is a schematic diagram illustrating the steps of a display panel driving method according to this application. See also... Figure 1 As shown, this application discloses a method for driving a display panel, including the following steps: S110: Obtain the data voltage of one positive polarity channel and one negative polarity channel of the current frame; S120: Calculate the difference between the grayscale value of the data voltage of the positive polarity channel and the grayscale value of the data voltage of the negative polarity channel; S130: Compare the absolute value of the difference with the grayscale difference threshold, and control the driving level of the positive polarity channel and the driving level of the negative polarity channel according to the comparison result. S131: When the difference is less than the gray level difference threshold, the driving level of the positive polarity channel and the driving level of the negative polarity channel are controlled by a standard preset level respectively. S132: When the difference is greater than or equal to the grayscale difference threshold, the driving level of the positive polarity channel and the driving level of the negative polarity channel are controlled by the first preset level respectively. Wherein, the first preset gear is greater than or less than the standard preset gear, and the larger the driving gear, the faster the data voltage of the positive polarity channel or the data voltage of the negative polarity channel reaches the target potential.

[0021] This application monitors one positive and one negative channel of the current frame. When the difference between the grayscale values ​​of the positive and negative data voltages exceeds a grayscale difference threshold, it indicates that image retention will occur when switching to other grayscale levels, requiring compensation for the data voltages of these two channels. By adjusting the drive levels of the positive and negative channels containing the two data voltages, the feedthrough voltages of the two significantly different data voltages are brought closer together, thereby bringing the feedthrough voltages of the two significantly different grayscale levels closer together. This ensures that the optimal common voltage is set almost identically, thus improving the image retention phenomenon caused by the significant difference in grayscale levels.

[0022] The advantage of this embodiment lies in that it identifies the grayscale values ​​of the data voltages of a positive and a negative channel, calculates the difference between them, and this difference is generally an absolute value. The grayscale values ​​are generally unsigned, being only natural numbers. For example, if there are 256 grayscale values ​​in the grayscale table, they correspond to grayscale levels 0 to 255. When the difference is greater than a grayscale difference threshold, for example, grayscale level 128 is used as the grayscale difference threshold in the range of 0 to 255. Grayscale levels 1 and 130, 120 and 255, etc., all have differences greater than the grayscale difference threshold, thus compensating for the data signals at grayscale levels 1 and 130 that are about to be output. Compared to schemes that only identify high and low grayscale levels, this application compares the difference; that is, when the grayscale difference between two data signal voltages satisfies a condition greater than the grayscale difference threshold, compensation is simultaneously applied to both the low and high grayscale data voltages, improving the precision of the compensation. It is understood that the grayscale values ​​mentioned in this application are only numbers and do not represent positive or negative polarity.

[0023] In this embodiment, the positive and negative channels are adjacent positive and negative channels. Generally, a display panel has at least one data driver chip, which contains multiple positive and multiple negative channels, the number of which is related to the number of data lines. The data driver chip transmits data voltage signals to the data lines through the positive and negative channels. At any given time, using a dot-inverting drive method, half of the data lines are positive channels and half are negative channels. In this embodiment, the positive and negative channels corresponding to two adjacent data lines in a row are detected.

[0024] Figure 2 This is a schematic diagram of grayscale voltage and feedthrough voltage according to an embodiment of this application. See also... Figure 2As shown, when a high grayscale data voltage, such as a positive polarity data voltage with a grayscale value of 255, is denoted as V255+, when a polarity reversal scheme is used, the negative polarity data voltage of the next frame is V255-, which is a negative polarity data voltage with a grayscale value of 255. Due to the existence of the feedthrough voltage, the actual displayed V255+ is represented by a dashed line, and there is a voltage difference between it and the ideal solid line portion of V255+. This voltage difference is the feedthrough voltage, and the feedthrough voltage Vkb at this time is equal to ΔV255. When a low grayscale data voltage, such as a positive polarity data voltage with a grayscale value of 0, is denoted as V0+, when a polarity reversal scheme is used, the negative polarity data voltage of the next frame is V0-, which is a negative polarity data voltage with a grayscale value of 0. Due to the existence of the feedthrough voltage, the actual displayed V0- is represented by a dashed line, while the ideal case is the solid line portion of V0-, and its feedthrough voltage is ΔV0. Since the feedthrough voltage is related to the liquid crystal capacitor Clc, the storage capacitor Cst, and the gate-source voltage difference of the thin-film transistor, the feedthrough voltage ΔV0 when the gray level value is 0 is less than ΔV255, which makes the corresponding optimal common voltage Vcom different.

[0025] To address this, this application modifies the driving level of the positive or negative channel, thereby altering the time it takes for the data voltage to reach the target potential by employing different driving levels. For example... Figure 2 In the V255+ configuration, adjusting the drive capability (increasing the drive level) allows the V255+ to reach the target potential (corresponding to its ideal solid line portion) more quickly. For the V255- configuration, the drive level needs to be decreased, causing the voltage to reach the target potential more slowly, thus making the potential of the V255- closer to the ideal solid line portion.

[0026] The aforementioned difference is an absolute value, encompassing two scenarios: first, the grayscale value of the positive channel is greater than that of the negative channel; second, the grayscale value of the negative channel is greater than that of the positive channel. Different gear control methods are applied to each of these scenarios.

[0027] Specifically, step S120 includes: S121a: When the grayscale value of the data voltage of the positive polarity channel is greater than the grayscale value of the data voltage of the negative polarity channel, the difference between the grayscale value of the data voltage of the positive polarity channel and the grayscale value of the data voltage of the negative polarity channel is calculated as the first difference value. Step S132 includes: S132a: When the first difference is greater than or equal to the grayscale difference threshold, one or n gears are added on the basis of the standard preset gears as driving gears for controlling the positive polarity channel and the negative polarity channel; where n is a natural number greater than 1.

[0028] In this embodiment, a judgment is also made on the grayscale value of the data voltage of the positive polarity channel and the grayscale value of the data voltage of the negative polarity channel. When the grayscale value of the data voltage of the positive polarity channel is larger, it is necessary to raise the potential of the data voltage of the positive polarity channel and raise the potential of the data voltage of the negative polarity channel.

[0029] Taking a driving voltage of 100mV corresponding to a certain level as an example. When the standard preset level for driving a certain grayscale is 1, the corresponding driving voltage is 10V. When a level is added to the standard preset level, the corresponding driving voltage is 10.1V. For example, if the driving voltage at the standard preset level of 255 grayscale is 10V, then when comparing the 255 grayscale of the positive channel with any grayscale below 128 in the negative channel, the difference is greater than or equal to 128 grayscale. Therefore, by increasing the driving level of the positive channel to drive it at 10.1V, the feedthrough voltage of the 255 grayscale in the positive channel is reduced, thus causing the optimal common voltage corresponding to that grayscale to shift upward. When the corresponding negative polarity channel, such as gray level 120, is driven at a higher absolute value by a higher driving voltage, the feedthrough voltage of gray level 120 in its negative polarity channel increases, thereby causing the optimal common voltage to shift downward. Ultimately, the feedthrough voltage ΔV255 corresponding to gray level 255 mentioned above is equal to the feedthrough voltage ΔV120 corresponding to gray level 120.

[0030] In this embodiment, the driving voltage range for one gear setting is from 100mV to 500mV. The grayscale voltage range in this embodiment is from 0.7V to 14V. When the grayscale voltage is greater than the common voltage Vcom, the polarity is positive. When the grayscale voltage is less than the common voltage Vcom, the polarity is negative.

[0031] This corresponds to the second scenario where the grayscale value of the negative polarity channel is greater than that of the positive polarity channel. Specifically, step S120 includes: S121b: When the grayscale value of the data voltage of the positive polarity channel is less than the grayscale value of the data voltage of the negative polarity channel, the difference between the grayscale value of the data voltage of the positive polarity channel and the grayscale value of the data voltage of the negative polarity channel is calculated as the second difference value. S132b: When the second difference is greater than or equal to the grayscale difference threshold, reduce the number of gears by 1 or n based on the standard preset gears, and use this as the driving gear for controlling the positive polarity channel and the driving gear for the negative polarity channel; where n is a natural number greater than 1.

[0032] In this embodiment, the situation is exactly the opposite of the previous one. The grayscale value of the data voltage in the negative channel is relatively large. In practice, the feedthrough voltage causes this grayscale value to shift downwards due to the negative polarity. Therefore, by reducing the drive level, the time it takes for the data voltage of the corresponding grayscale value to reach the target potential is increased, and the corresponding data voltage shifts upwards, that is, the absolute value of the data voltage decreases. Similarly, for the positive channel, the drive level also needs to be reduced, so that the data voltage of the positive channel reaches the target potential with a delay, causing its optimal common voltage to shift downwards.

[0033] Taking a driving voltage of 100mV corresponding to a certain level as an example. When the standard preset level for driving a certain grayscale is 1, the corresponding driving voltage is 10V. When the standard preset level is reduced by one level, the corresponding driving voltage is 9.9V. For example, if the driving voltage at the standard preset level of 255 grayscale is 10V, then when comparing the 255 grayscale of the negative channel with any grayscale below 128 of the positive channel, the difference is greater than or equal to 128 grayscale. Therefore, by reducing the driving level of the positive channel to drive it at 9.9V, the optimal common voltage corresponding to the 255 grayscale of the negative channel shifts upward. Similarly, the optimal common voltage corresponding to its lower negative grayscale shifts upward, making the feedthrough voltages of both approach the same.

[0034] In this embodiment, the data signal is not simply distinguished by high and low gray levels. Instead, the absolute values ​​of the data voltages output by the positive and negative polarity channels are compared. When the difference in their absolute values ​​(i.e., the difference in gray level values ​​mentioned above) is greater than the gray level difference threshold, it indicates that the data voltages output by the positive and negative polarity channels are prone to ghosting and need to be compensated.

[0035] Understandably, in the grayscale mapping table corresponding to its standard preset level, each grayscale value is assigned a data voltage. When the first preset level needs to add or remove a level from the standard preset level, the data voltage corresponding to each grayscale value in the grayscale mapping standard of the standard preset level will increase or decrease by 100mV respectively.

[0036] Figure 3 This is a schematic diagram illustrating the steps of the second display panel driving method of this application. See [link / reference]. Figure 3 As shown, in one embodiment, compensation may be implemented for only one of the two situations described above, while no compensation may be performed for the other situation.

[0037] Specifically, the process following step S130 also includes: S210: Acquire the data voltage of one positive polarity channel and one negative polarity channel for multiple consecutive frames; S220a: When the grayscale value of the data voltage of the positive polarity channel in the previous frame is greater than the grayscale value of the data voltage of the negative polarity channel, the difference between the grayscale value of the data voltage of the positive polarity channel and the grayscale value of the data voltage of the negative polarity channel is calculated as the first difference. S230a: When the first difference is greater than or equal to the grayscale difference threshold, one or n levels are added on the basis of the standard preset levels, which are used as the driving levels for controlling the positive polarity channel and the driving levels for the negative polarity channel. S220b: When the grayscale value of the data voltage of the positive polarity channel in the next frame is less than the grayscale value of the data voltage of the negative polarity channel, the difference between the grayscale value of the data voltage of the positive polarity channel and the grayscale value of the data voltage of the negative polarity channel is calculated as a second difference. S230b: When the second difference is greater than or equal to the grayscale difference threshold, the standard preset position is used as the driving position of the positive polarity channel and the driving position of the negative polarity channel.

[0038] In this embodiment, only the first difference is compensated, while the second difference is driven at a standard preset level. For polarity reversal, especially in static images, each sub-pixel differs only in polarity in adjacent frames, and its grayscale value is equal. That is, the above two situations alternate between adjacent frames, so compensation only needs to be performed once in adjacent frames. By reducing the number of compensations, the power consumption of the corresponding data driving chip is reduced.

[0039] Of course, in another embodiment, compensation can be performed separately for the second case, while no compensation is performed for the first case. That is, when the first difference is greater than or equal to the grayscale difference threshold, the driving positions of the positive and negative channels are controlled by the standard preset positions. When the second difference is greater than or equal to the grayscale difference threshold, one or n positions are added to the standard preset positions as driving positions for the positive and negative channels.

[0040] In another embodiment, considering that image retention is actually affected by DC bias, and that compensation is only applied to the positive channel or the negative channel when the grayscale is high in consecutive frames, using a single-level control method for a long time can easily accumulate deviations and cause unidirectional offset. Therefore, for the above two situations, compensation can be applied by increasing or decreasing the level in alternating frames.

[0041] Specifically, in multiple consecutive frames, the grayscale values ​​of the data voltages of the positive and negative channels are acquired respectively. When the grayscale value of the data voltage of the positive channel in the previous frame is greater than the grayscale value of the data voltage of the negative channel, steps S121a and S132a mentioned above are executed. When the grayscale value of the data voltage of the positive channel in the current frame is less than the grayscale value of the data voltage of the negative channel, steps S121b and S132b mentioned above are executed.

[0042] In this embodiment, by using the method of increasing and decreasing the level in alternating frames, the offset of the feedthrough voltage is made more uniform during long-term compensation, and the problem of unidirectional offset caused by long-term single-level control is avoided.

[0043] Of course, compensation can also be performed alternately every two or more consecutive frames. That is, in the first two frames, compensation is performed only for one case. For example, steps S121a and S132a are executed; in the second two frames, compensation is performed for the second case, such as steps S121b and S132b.

[0044] Based on the above embodiments, considering the different differences between 255 gray levels and 0, 32, 64, 96, and 128 gray levels, the feedthrough voltage corresponding to different differences when two adjacent channels output the above two gray levels will also be different. Therefore, in this embodiment, different levels can be set for different differences.

[0045] Specifically, the greater the difference between the difference value and the grayscale difference threshold, the greater the level difference between the first preset level and the standard preset level.

[0046] In this embodiment, when comparing multiple differences, the larger the difference, the larger the corresponding first preset level. This first preset level is the larger the level increase from the standard preset level. For example, the difference between 255 grayscale and 64 grayscale is 191, and its corresponding first preset level is equal to the standard preset level increased or decreased by 2 levels. If one level is 100mV, this corresponds to an increase or decrease of 200mV. Similarly, the difference between 255 grayscale and 0 grayscale is 255, and its corresponding first preset level is equal to the standard preset level increased by 3 levels. If one level is 100mV, this corresponds to an increase or decrease of 300mV.

[0047] Specifically, the display panel further includes a grayscale mapping table, which sets the grayscale values ​​of all the data signals. The grayscale mapping table includes x sequentially increasing grayscale values, where x is an even number greater than 0, the minimum grayscale value is 0, the maximum grayscale value is x-1, and the grayscale difference threshold is equal to x / 2.

[0048] In this embodiment, the grayscale difference threshold is set using the median grayscale value. This filters out data from adjacent channels where the difference in data voltage is small, such as +255 grayscale and -255 grayscale (the difference is 0), or +130 grayscale and -150 grayscale (the difference is 20). Although these grayscale values ​​are all higher than the grayscale difference threshold, the feedthrough voltages corresponding to the two grayscale values ​​are actually quite close, resulting in a low probability of image retention, thus eliminating the need for compensation.

[0049] Taking x as 256 as an example, the grayscale mapping table includes 256 sequentially increasing grayscale values, and the grayscale difference threshold is 128. When the difference is greater than 128 and less than 144, the first preset level is increased or decreased by one level based on the standard preset level; when the difference is greater than 144 and less than 176, the first preset level is increased or decreased by two levels based on the standard preset level; when the difference is greater than 176 and less than 208, the first preset level is increased or decreased by three levels based on the standard preset level; when the difference is greater than 208 and less than 240, the first preset level is increased or decreased by four levels based on the standard preset level; when the difference is greater than 240 and less than 255, the first preset level is increased or decreased by five levels based on the standard preset level.

[0050] Each gear level corresponds to a drive voltage of 100mV, meaning that each gear level increases or decreases the drive voltage by 100mV. Five gear levels would then increase or decrease the drive voltage by 500mV.

[0051] In this embodiment, by making the two gray levels with a large difference have stronger or weaker driving capabilities, the data voltage offset value output by the two channels with a large difference is adjusted.

[0052] Figure 4 This is a schematic diagram of the driving circuit of the display panel of this application. Figure 5 This is a schematic diagram of the computing circuit of this application, see [link / reference]. Figures 4 to 5As shown, corresponding to the above-described driving method for a display panel, this application also discloses a driving circuit 100 for a display panel. This driving circuit 100 is used to execute the driving method of any of the above embodiments. The driving circuit 100 includes a timing controller 110, a calculation circuit 120, and a data driving circuit 130. The timing controller 110 is used to acquire the data voltage of a positive channel 131 and a negative channel 132 in the current frame. The calculation circuit 120 is used to calculate the difference between the grayscale value of the data voltage of the positive channel 131 and the grayscale value of the data voltage of the negative channel 132, and compare the absolute value of the difference with a grayscale difference threshold. The data driving circuit 130 includes at least one positive channel 131 and one negative channel 132, with each positive channel 131 and negative channel 132 connected to a data line. The data driving circuit 130 in this embodiment is the aforementioned data driving chip, which is typically bonded to the display panel.

[0053] Specifically, when the difference is less than the grayscale difference threshold, the timing controller 110 uses a standard preset setting to control the driving setting of the positive channel 131 and the driving setting of the negative channel 132 respectively; when the difference is greater than or equal to the grayscale difference threshold, the timing controller 110 uses a first preset setting to control the driving setting of the positive channel 131 and the driving setting of the negative channel 132 respectively; wherein, the first preset setting is greater than or less than the standard preset setting, and the larger the driving setting, the faster the data voltage of the positive channel 131 or the data voltage of the negative channel 132 reaches the target potential.

[0054] Specifically, the calculation circuit 120 generally includes a subtractor 121 and a comparator 122. The subtractor has a first input terminal 121a and a second input terminal 121b, which receive the data voltages of the positive polarity channel 131 and the negative polarity channel 132, respectively. The output terminal of the subtractor 121 is connected to the first comparison input terminal 122a of the comparator 122, and the second comparison input terminal 122b of the comparator 122 is connected to the grayscale difference threshold. When the difference output by the subtractor 121 is greater than or equal to the grayscale difference threshold, the comparator 122 outputs a control signal. This control signal is transmitted to the timing controller 110, which controls the driving level of the positive polarity channel 131 and the negative polarity channel 132 corresponding to the data driving circuit 130. Since the positive polarity channel 131 and negative polarity channel 132 of the data driving circuit 130 can be adjusted to different levels, the driving capability of the data driving circuit 130 can be selected according to different control signals, thereby adjusting the rising and falling speed of the data.

[0055] Figure 6This is a schematic diagram of the steps of the third display panel driving method of this application, see [link / reference]. Figure 6 As shown, in another embodiment, the step further includes S110: S101: Obtain the data voltage of a preset area for a consecutive preset number of frames.

[0056] By continuously acquiring data voltage data from a preset region across multiple frames (e.g., 100, 200, or 1000 frames), and analyzing the changes within this consecutive frame count, it's determined whether the scene is static. Generally, in a static scene, each sub-pixel corresponds to the same grayscale value, but the polarity changes. This is addressed by inverting the polarity between frames. Therefore, a timing controller can monitor the data voltage data from a preset region across multiple consecutive frames, determining whether a switch from a static to a dynamic scene is needed by observing changes in the grayscale value of each sub-pixel. The preset region can be randomly selected, containing at least 6x6 sub-pixels, which is generally the smallest area visible to the naked eye.

[0057] S102: If the data voltage in the preset area does not change for a preset number of consecutive frames, it is determined to be a static image; after the preset number of frames, the control data line is connected to the common electrode line for discharge.

[0058] In this embodiment, when the image is determined to be static and does not switch to a dynamic image after a preset number of frames, the driving method corresponding to this embodiment does not need to be executed. Instead, discharge is achieved by connecting the data line to the common electrode line after the preset number of frames. The preset number of frames can be 500 to 1000 frames. In the discharge control, by turning on all clock signals and connecting the data line to the common voltage line corresponding to the common voltage Vcom, charge is released, reducing the impact of long-term DC accumulation.

[0059] S103: If there is a change in the data voltage in the preset area for a consecutive preset number of frames, it is determined that the static screen has been switched to the dynamic screen, and step S110 is performed.

[0060] In a continuous 1000 frames of data, the first 200 frames are determined to be static images, followed by dynamic images. To avoid ghosting during transitions between static and dynamic images, compensation is needed for the first 200 static frames. Generally, when the preset frame rate of S102 is 500 to 1000 frames, during a transition between static and dynamic images within 500 frames, the static images cannot meet the requirement of 500 consecutive frames, thus preventing discharge. In other words, a short period of static imagery cannot meet the standard for charge release. Therefore, the driving method in this embodiment can only be implemented in this situation. Generally, real-time adjustment of the data driving level increases the power consumption of the data driving. Therefore, to reduce power consumption, a time-based judgment standard is added. The timing controller detects changes in data within the preset frame rate and initiates different compensation methods.

[0061] Figure 7 This is a schematic diagram of the display panel of this application; see below. Figure 7 As shown, this application also discloses a display device 300, which includes a display panel 200 and a driving circuit 100, the driving circuit 100 being used to drive the display panel 200 to display.

[0062] It should be noted that the inventive concept of this application can form many embodiments, but due to the limited space of the application documents, they cannot all be listed. Therefore, without conflict, the embodiments described above or the technical features can be arbitrarily combined to form new embodiments. After the embodiments or technical features are combined, the original technical effect will be enhanced.

[0063] The above description, in conjunction with specific optional embodiments, provides a further detailed explanation of this application and should not be construed as limiting the specific implementation of this application to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the concept of this application, and all such modifications or substitutions should be considered within the scope of protection of this application.

Claims

1. A driving method for a display panel, characterized in that, Including the following steps: Obtain the data voltage of one positive polarity channel and one negative polarity channel in the current frame; Calculate the difference between the grayscale value of the data voltage of the positive polarity channel and the grayscale value of the data voltage of the negative polarity channel; The absolute value of the difference is compared with the grayscale difference threshold, and the driving level of the positive polarity channel and the driving level of the negative polarity channel are controlled according to the comparison result. Wherein, when the difference is less than the gray level difference threshold, the driving level of the positive polarity channel and the driving level of the negative polarity channel are controlled by a standard preset level respectively. When the difference is greater than or equal to the grayscale difference threshold, the driving level of the positive polarity channel and the driving level of the negative polarity channel are controlled by the first preset level respectively. Wherein, the first preset gear is greater than or less than the standard preset gear, and the larger the driving gear, the faster the data voltage of the positive polarity channel or the data voltage of the negative polarity channel reaches the target potential.

2. The driving method for the display panel according to claim 1, characterized in that, The step of calculating the difference between the grayscale value of the data voltage of the positive polarity channel and the grayscale value of the data voltage of the negative polarity channel includes: When the grayscale value of the data voltage of the positive polarity channel is greater than the grayscale value of the data voltage of the negative polarity channel, the difference between the grayscale value of the data voltage of the positive polarity channel and the grayscale value of the data voltage of the negative polarity channel is calculated as the first difference value. The step of controlling the driving level of the positive channel and the driving level of the negative channel respectively using a first preset level when the difference is greater than or equal to the gray level difference threshold includes: When the first difference is greater than or equal to the grayscale difference threshold, one or n gears are added on the basis of the standard preset gears as driving gears for controlling the positive polarity channel and driving gears for the negative polarity channel. Where n is a natural number greater than 1.

3. The driving method for the display panel according to claim 1, characterized in that, The step of calculating the difference between the grayscale value of the data voltage of the positive polarity channel and the grayscale value of the data voltage of the negative polarity channel includes: When the grayscale value of the data voltage of the positive polarity channel is less than the grayscale value of the data voltage of the negative polarity channel, the difference between the grayscale value of the data voltage of the positive polarity channel and the grayscale value of the data voltage of the negative polarity channel is calculated as the second difference value. The step of controlling the driving level of the positive channel and the driving level of the negative channel respectively using a first preset level when the difference is greater than or equal to the gray level difference threshold includes: When the second difference is greater than or equal to the grayscale difference threshold, one or n levels are reduced from the standard preset levels as the driving levels for controlling the positive polarity channel and the negative polarity channel. Where n is a natural number greater than 1.

4. The driving method for a display panel according to claim 1, characterized in that, The greater the difference between the difference and the grayscale difference threshold, the greater the level difference between the first preset level and the standard preset level.

5. The driving method for a display panel according to claim 4, characterized in that, The display panel also includes a grayscale map table, which contains grayscale values ​​for all the data signals. The grayscale mapping table includes x sequentially increasing grayscale values, where x is an even number greater than 0, the minimum grayscale value is 0, the maximum grayscale value is x-1, and the grayscale difference threshold is equal to x / 2.

6. The driving method for a display panel according to claim 5, characterized in that, The grayscale mapping table includes 256 sequentially increasing grayscale values, and the grayscale difference threshold is 128. When the difference is greater than 128 and less than 144, the first preset gear is based on the standard preset gear with one gear added or removed; When the difference is greater than 144 and less than 176, the first preset gear is based on the standard preset gear with two gears added or removed. When the difference is greater than 176 and less than 208, the first preset gear is based on the standard preset gear with three gears added or removed. When the difference is greater than 208 and less than 240, the first preset gear is based on the standard preset gear with four gears added or removed; When the difference is greater than 240 and less than 255, the first preset gear is based on the standard preset gear with five gears added or removed.

7. The driving method for a display panel according to claim 2, characterized in that, The step of comparing the absolute value of the difference with the grayscale difference threshold and controlling the driving level of the positive and negative channels based on the comparison result further includes: Acquire the data voltage of one positive polarity channel and one negative polarity channel across multiple consecutive frames; When the grayscale value of the data voltage of the positive polarity channel in the previous frame is greater than the grayscale value of the data voltage of the negative polarity channel, the difference between the grayscale value of the data voltage of the positive polarity channel and the grayscale value of the data voltage of the negative polarity channel is calculated as the first difference. When the first difference is greater than or equal to the grayscale difference threshold, one or more gears are added on the basis of the standard preset gears as driving gears for controlling the positive polarity channel and driving gears for the negative polarity channel. When the grayscale value of the data voltage of the positive polarity channel in the next frame is less than the grayscale value of the data voltage of the negative polarity channel, the difference between the grayscale value of the data voltage of the positive polarity channel and the grayscale value of the data voltage of the negative polarity channel is calculated as the second difference value. When the second difference is greater than or equal to the grayscale difference threshold, the driving gear of the positive polarity channel and the driving gear of the negative polarity channel are controlled by the standard preset gear.

8. The driving method for a display panel according to claim 1, characterized in that, The step of obtaining the data voltage of one positive polarity channel and one negative polarity channel of the current frame includes the following: Obtain the data voltage of a preset region for a consecutive preset number of frames; If the data voltage in the preset area does not change for a preset number of consecutive frames, it is determined to be a static image; after the preset number of frames, the control data line is connected to the common electrode line to discharge; If there is a change in the data voltage in the preset area for a consecutive preset number of frames, it is determined that the screen has switched from a static screen to a dynamic screen, and the steps of obtaining the data voltage of one positive polarity channel and one negative polarity channel of the current frame are performed.

9. A driving circuit for a display panel, characterized in that, The driving method for the display panel according to any one of claims 1 to 8, wherein the driving circuit comprises: The timing controller is used to acquire the data voltage of one positive channel and one negative channel of the current frame; A computing circuit is used to calculate the difference between the grayscale value of the data voltage of the positive polarity channel and the grayscale value of the data voltage of the negative polarity channel, and to compare the absolute value of the difference with a grayscale difference threshold; and A data driving circuit includes at least one positive channel and one negative channel, wherein one of the positive channels and one of the negative channels are respectively connected to a data line; Wherein, when the difference is less than the gray level difference threshold, the timing controller uses a standard preset setting to control the driving setting of the positive polarity channel and the driving setting of the negative polarity channel respectively. When the difference is greater than or equal to the grayscale difference threshold, the timing controller uses a first preset setting to control the driving setting of the positive polarity channel and the driving setting of the negative polarity channel respectively. Wherein, the first preset gear is greater than or less than the standard preset gear, and the larger the driving gear, the faster the data voltage of the positive polarity channel or the data voltage of the negative polarity channel reaches the target potential.

10. A display device, characterized in that, The display device includes a display panel and a driving circuit, the driving circuit including the driving circuit as described in claim 9, the driving circuit being used to drive the display panel to display.

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