Common voltage regulation method, common voltage regulation circuit and display device

Abstract

The present application discloses a common voltage regulation method, a common voltage regulation circuit, and a display device, relating to the field of display technology. The common voltage regulation method comprises the following steps: a display panel enters a variable refresh rate mode; obtains the refresh rate of the current frame, and obtains a corresponding common voltage value based on the current frame refresh rate; outputs the common voltage value to drive the display panel; detects a flicker value of the display panel and evaluates the magnitude of the flicker value. If the flicker value is within a preset threshold, step S2 is repeated until the display panel exits the variable refresh rate mode; if the flicker value exceeds the preset threshold, the corresponding common voltage is obtained based on the flicker value and adjusted, and step S4 is re-executed; the preset threshold is a partial flicker value at the current frame refresh rate. This common voltage regulation method can adjust the common voltage value in real time, thereby improving display anomalies of the display panel.

Description

Technical Field

[0001] The present application relates to the field of display technology, and in particular to a common voltage regulation method, a common voltage regulation circuit, and a display device. Background Art

[0002] Currently, gaming monitors are gradually developing towards high resolution, high refresh rate, and curved screens. Market demand is growing, and high-end customers are also demanding higher quality displays. Gaming monitors are typically liquid crystal displays (LCDs). During the production process, LCDs exhibit a certain degree of flicker. Excessive flicker can cause visual fatigue and discomfort. Typically, LCDs require flicker adjustment before shipment to ensure the flicker level is within a predetermined range for optimal viewing experience.

[0003] Because flicker is related to the common voltage (Vcom), the typical flicker adjustment method is to adjust Vcom to adjust the flicker of the display panel. However, Vcom varies with the refresh rate and is affected by external settings. This can cause the common voltage received by pixels at different refresh rates to deviate from the actual common voltage required, resulting in display anomalies. Summary of the Invention

[0004] The purpose of this application is to provide a common voltage regulation method, a common voltage regulation circuit and a display device, which can adjust the value of the common voltage in real time and improve the display abnormality problem of the display panel.

[0005] This application discloses a common voltage regulation method, comprising the steps of:

[0006] S1: The display panel enters variable refresh rate mode;

[0007] S2: Get the refresh rate of the current frame, and get the corresponding common voltage value according to the refresh rate of the current frame;

[0008] S3: output common voltage value to drive the display panel;

[0009] S4: Detecting the flicker value of the display panel and evaluating the flicker value. If the flicker value is within a preset threshold, repeating step S2 until the display panel exits the variable refresh rate mode. If the flicker value exceeds the preset threshold, adjusting the corresponding common voltage based on the flicker value and re-executing step S4.

[0010] The preset threshold is a partial flicker value at the current frame refresh rate.

[0011] Optionally, step S2 includes:

[0012] S20: Obtaining the refresh rate of the current frame according to the duration of the vertical blanking period of the current frame;

[0013] S21: According to the refresh rate of the current frame, calling the pre-stored flicker value and common voltage data table to obtain the optimal common voltage value corresponding to the current frame refresh rate;

[0014] There are a plurality of flicker value and common voltage data tables, each of which has a plurality of groups of data, and each group of data corresponds to a flicker value and a common voltage value associated with the flicker value.

[0015] Optionally, the flicker value and the common voltage data table are obtained by testing through the following steps:

[0016] Output test video to the display panel;

[0017] Get the current refresh rate of the display panel based on the output test video;

[0018] Play the test video, capture the display panel image, and record the flicker value and common voltage of the display panel at the current refresh rate;

[0019] Switch to different common voltages and play test videos multiple times to create a data table of flicker values ​​and common voltages at the current refresh rate.

[0020] After the refresh rate is switched, the above steps are repeated to obtain a flicker value and a common voltage data table under the refresh rate after switching.

[0021] Optionally, obtaining the current refresh rate of the display panel according to the output test video includes:

[0022] Transmitting the test video to the conversion module to convert it into a digital signal;

[0023] The digital signal is transmitted to the time difference calculation module to be converted into a time difference signal, and the current refresh rate of the display panel is calculated.

[0024] Optionally, step S4 includes:

[0025] S40: Detecting the display brightness of the display panel within a preset frame number range;

[0026] S41: Calculate the average display brightness within a preset frame number range to obtain a flicker value;

[0027] The preset frame number range is between 1 and 10 frames.

[0028] Optionally, step S4 further includes:

[0029] S42: comparing the detected flicker value with a preset threshold at the current refresh rate;

[0030] S43: If the detected flicker value is within the preset threshold, maintain normal display and repeat step S2 until the display panel exits the variable refresh rate mode; if the detected flicker value exceeds the preset threshold, adjust the common voltage value according to the detected flicker value;

[0031] S44: Output the adjusted common voltage value to the display panel, and then jump to step S40;

[0032] When the detected flicker value exceeds a preset threshold, the common voltage value is adjusted according to the detected flicker value through the flicker value and the common voltage data table.

[0033] Optionally, the following steps are further included between step S43 and step S44:

[0034] S431: Writing the adjusted common voltage value into the corresponding flicker value and common voltage data table as new data.

[0035] Optionally, step S3 includes:

[0036] S30: Output the common voltage value to the power management integrated circuit;

[0037] S31: During the vertical blanking period of the next frame, the power management integrated circuit outputs the corresponding common voltage to the display panel.

[0038] The present application also discloses a common voltage regulation circuit, which is applied to any of the common voltage regulation methods described above, comprising:

[0039] A first detection module detects whether the display panel enters a variable refresh rate mode;

[0040] A second detection module detects the refresh rate of the display panel;

[0041] A third detection module detects a flicker value of the display panel;

[0042] a storage module for storing a plurality of common voltage values; and

[0043] a control module electrically connected to the first detection module, the second detection module, the third detection module, and the storage module;

[0044] wherein, when the first detection module detects that the display panel enters the variable refresh rate mode, the second detection module detects the refresh rate of the display panel, the control module calls the corresponding common voltage value stored in the storage module according to the refresh rate detected by the second detection module and outputs it to the display panel, the third detection module detects the flicker value of the display panel, and the control module determines whether to adjust the common voltage value according to the flicker value detected by the third detection module;

[0045] Among them, if the flicker value does not exceed the preset threshold, it is determined that no adjustment is required; if the flicker value exceeds the preset threshold, it is determined that adjustment is required, and the control module obtains the corresponding common voltage according to the flicker value and adjusts the output to drive the display panel.

[0046] The present application also discloses a display device, including a display panel and the common voltage regulation circuit as described above, wherein the common voltage regulation circuit is configured to execute the common voltage regulation method as described above.

[0047] The common voltage adjustment method of the present application detects whether the display panel enters the variable refresh rate mode, obtains the refresh rate of the current frame of the display panel, obtains the corresponding common voltage value according to the refresh rate of the current frame to preliminarily adjust the common voltage of the display panel, and then detects the flicker value of the display panel, compares the detected flicker value with the preset threshold value, and determines whether the display panel needs to continue to adjust the common voltage, so that the adjusted common voltage can change with the refresh rate of the display panel, and can be adjusted a second time according to the actual situation when the display panel is displayed, until the flicker value of the display panel is within the optimal preset threshold range. In general, the common voltage adjustment in the display panel can not only change with the change of the refresh rate, but also can be adjusted in real time according to the situation of using the switched common voltage, so that the deviation between the common voltage received by the pixel at different refresh rates and the actual required common voltage is reduced to a minimum or no deviation, thereby improving the display abnormality problem of the display panel. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] The included drawings are used to provide a further understanding of the embodiments of the present application, which constitute a part of the specification, are used to illustrate the implementation methods of the present application, and together with the text description, explain the principles of the present application. Obviously, the drawings described below are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without inventive work. In the drawings:

[0049] Figure 1 This is a flowchart of the steps of a common voltage regulation method according to the first embodiment of the present application;

[0050] Figure 2This is a detailed flow chart of the steps of a common voltage regulation method according to the first embodiment of the present application;

[0051] Figure 3 is a structural diagram of a common voltage regulation circuit according to the second embodiment of the present application;

[0052] Figure 4 It is a structural schematic diagram of a display device according to the third embodiment of the present application.

[0053] Among them, 100, common voltage regulation circuit; 110, first detection module; 120, second detection module; 130, third detection module; 140, storage module; 150, control module; 200, display panel; 300, display device. DETAILED DESCRIPTION

[0054] It should be understood that the terms used herein, the specific structures and functional details disclosed are only for describing specific embodiments and are representative. However, the present application can be implemented in many alternative forms and should not be construed as being limited to the embodiments described herein.

[0055] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate relative importance or implicitly specify the quantity of the technical features indicated. Therefore, unless otherwise specified, a feature specified as "first" or "second" may explicitly or implicitly include one or more of such features; "plurality" means two or more. The term "comprising" and any variations thereof are intended to be non-exclusive inclusion, and one or more other features, integers, steps, operations, units, components, and / or combinations thereof may be present or added.

[0056] In addition, terms indicating orientation or positional relationships such as “center,” “lateral,” “up,” “down,” “left,” “right,” “vertical,” “horizontal,” “top,” “bottom,” “inside,” and “outside” are described based on the orientation or relative positional relationships shown in the accompanying drawings. They are merely simplified descriptions for the convenience of describing the present application, and do not indicate that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they should not be understood as limitations on the present application.

[0057] Furthermore, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood broadly, and may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediary; or internal communication between two components. Those skilled in the art will understand the specific meanings of these terms in this application based on specific circumstances.

[0058] The present application is described in detail below with reference to the accompanying drawings and optional embodiments. It should be noted that, under the premise of no conflict, the embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0059] like Figure 1 As shown, as a first embodiment of the present application, a common voltage regulation method is disclosed. The method is specifically applied to a display device and to a variable refresh rate mode of a display panel. It should be noted that the variable refresh rate mode of the display panel refers to a refresh rate switching mode. The common voltage regulation method includes the steps of:

[0060] S1: The display panel enters variable refresh rate mode;

[0061] Specifically, when the display panel enters the variable refresh rate mode, the common voltage needs to be dynamically adjusted according to the change in the refresh rate to reduce the flickering of the display panel during display. When the display panel is in the fixed refresh rate mode, the common voltage can be used to drive the display panel based on the optimal common voltage value in the fixed refresh rate mode. It should be noted that the optimal common voltage value refers to the current refresh rate. When the display panel is driven by the common voltage, the flicker value of the display panel is at the minimum value (optimal value).

[0062] S2: Get the refresh rate of the current frame, and get the corresponding common voltage value according to the refresh rate of the current frame;

[0063] Specifically, after obtaining the refresh rate of the current frame, the preset common voltage value corresponding to the refresh rate of the current frame can be called according to the detected refresh rate of the current frame to adjust the common voltage. The flicker value of the corresponding common voltage value when driving the display panel at the current frame refresh rate is the optimal flicker value, so that the display effect of the display device applying the common voltage adjustment method can be optimized.

[0064] S3: output common voltage value to drive the display panel;

[0065] S4: Detecting the flicker value of the display panel and evaluating the flicker value. If the flicker value is within a preset threshold, repeating step S2 until the display panel exits the variable refresh rate mode. If the flicker value exceeds the preset threshold, adjusting the corresponding common voltage based on the flicker value and re-executing step S4.

[0066] Specifically, the common voltage corresponding to the refresh rate is obtained by detecting the refresh rate change. After adjusting the common voltage of the display panel, the flicker value of the display panel when in use is detected to evaluate whether the flicker value is within the preset flicker value range at the refresh rate of the current frame to determine whether the display panel needs to continue to be adjusted. It should be noted that the preset threshold is a range threshold close to the minimum flicker value at the current frame refresh rate. The flicker value within the preset threshold can be accepted by the user or recognized as an acceptable value by the industry.

[0067] The common voltage adjustment method provided in this embodiment detects whether the display panel enters the variable refresh rate mode, obtains the refresh rate of the current frame of the display panel, obtains the corresponding common voltage value according to the refresh rate of the current frame to preliminarily adjust the common voltage of the display panel, and then detects the flicker value of the display panel, compares the detected flicker value with the preset threshold value, and determines whether the display panel needs to continue to adjust the common voltage, so that the adjusted common voltage can change with the refresh rate of the display panel, and can be adjusted a second time according to the actual situation when the display panel is displayed, until the flicker value of the display panel is within the optimal preset threshold range. In general, the common voltage adjustment in the display panel can not only change with the change of the refresh rate, but also can be adjusted in real time according to the situation of using the switched common voltage, so that the deviation between the common voltage received by the pixel at different refresh rates and the actual required common voltage is reduced to a minimum or no deviation, thereby improving the display abnormality problem of the display panel.

[0068] The steps of the above embodiment will be further explained in detail below. Figure 2 As shown, step S2 includes:

[0069] S20: Obtaining the refresh rate of the current frame according to the duration of the vertical blanking period of the current frame;

[0070] S21: According to the refresh rate of the current frame, calling the pre-stored flicker value and common voltage data table to obtain the optimal common voltage value corresponding to the current frame refresh rate;

[0071] Specifically, the time period from the start of displaying one frame of image to the start of displaying the next frame of image on the display panel is called a frame period. A frame period includes a display stage and a vertical blanking period. The refresh rate of the current frame is obtained by detecting the length of the vertical blanking period. Then, based on the obtained refresh rate of the current frame, a set of flicker value and common voltage data tables corresponding to the current frame refresh rate are called to obtain the optimal common voltage value corresponding to the current frame refresh rate. The flicker value of the display panel driven under this common voltage value is the minimum value. It should be noted that there are multiple flicker value and common voltage data tables, each of which corresponds to a refresh rate value. Designers can set the data of the flicker value and common voltage data tables according to actual needs. Each flicker value and common voltage data table is provided with multiple groups of data, and each group of data corresponds to a flicker value and a common voltage value associated with the flicker value.

[0072] Take the refresh rate of the display panel as 60hz as an example: detect when the display panel enters the variable refresh rate mode, and obtain the refresh rate of the current frame as 60hz by detecting the length of the vertical blanking period of the current frame. Then call the flicker value and common voltage data table corresponding to 60hz, and select the common voltage value corresponding to the minimum flicker value in the flicker value and common voltage data table as the common voltage when the display panel is driven for the next frame.

[0073] As a further limitation of the above embodiment, step S4 includes:

[0074] S40: Detecting the display brightness of the display panel within a preset frame number range;

[0075] S41: Calculate the average display brightness within a preset frame number range to obtain a flicker value;

[0076] Specifically, the preset frame number range is between 1 and 10 frames. During detection, only one frame of the display panel can be detected, or multiple frames of the display panel can be detected to obtain the average value of the display brightness to ensure the accuracy of the obtained flicker value. It should be noted that designers can also select the preset frame number range according to actual needs, such as setting more frames, 20 frames or 30 frames, etc., to make the obtained flicker value more accurate.

[0077] S42: comparing the detected flicker value with a preset threshold at the current refresh rate;

[0078] Specifically, the preset threshold is the range value between the flicker value corresponding to the current refresh rate and the value close to the minimum flicker value in the public voltage data table. The detected flicker value needs to be compared with the flicker value corresponding to the current refresh rate and the data in the public voltage data table.

[0079] S43: If the detected flicker value is within the preset threshold, maintain normal display and repeat step S2 until the display panel exits the variable refresh rate mode; if the detected flicker value exceeds the preset threshold, adjust the common voltage value according to the detected flicker value;

[0080] S44: Output the adjusted common voltage value to the display panel, and then jump to step S40;

[0081] Specifically, if the detected flicker value is within the preset threshold, the common voltage will not be adjusted and normal display will be maintained until the vertical blanking period of the next frame is turned on, and step S2 will be repeated until the display panel exits the variable refresh rate mode; if the detected flicker value exceeds the preset threshold, it means that the output common voltage value has not reached the expected output common voltage value, and may be interfered by other external factors, resulting in the flicker value failing to reach the optimal value. Then, according to the detected flicker value, the flicker value corresponding to the current refresh rate and the corresponding flicker value data in the public voltage table, as well as its corresponding common voltage value, are called, and the corresponding common voltage value is output to the display panel for adjustment, and then step S40 is re-executed for detection until the detected flicker value is within the preset threshold; of course, a calculation unit can also be set, and according to the value of the detected flicker value exceeding the preset threshold, the common voltage value to be adjusted is obtained through the calculation unit for adjustment. Designers can choose the design according to actual needs, and there is no limitation here.

[0082] As a further limitation of the above embodiment, the above step S43 and step S44 further include the following steps:

[0083] S431: writing the adjusted common voltage value into the corresponding flicker value and common voltage data table as new data;

[0084] Specifically, after adjusting the common voltage value according to the current refresh rate, when the flicker value detected again exceeds the preset threshold, the common voltage value at this time corresponds to the detected flicker value, and it is written into the flicker value corresponding to the current refresh rate and the common voltage data table. The common voltage value adjusted according to the detected flicker value corresponds to the optimal flicker value, and it is written into the flicker value corresponding to the current refresh rate and the common voltage data table, so that the flicker value and the common voltage data table can be updated in real time according to usage. In this way, even if the output common voltage of the display device fails to reach the expected output common voltage value due to long-term use or other external factors, resulting in the flicker value not meeting the standard, the display device using this common voltage adjustment method can well avoid this situation, and can adjust the common voltage in real time by detecting changes in the flicker value, so that the flicker value can always be in the best state.

[0085] It should be noted that after adjusting the common voltage value based on the current refresh rate, if the flicker value detected again exceeds the preset threshold, the common voltage value adjusted based on the detected flicker value can be used directly without being recorded in the corresponding flicker value and common voltage data table. In this way, a judgment can be made each time based on the detected flicker value. If the detected flicker value is the optimal value, the data in the flicker value and common voltage data table is directly used. If the detected flicker value deviates from the optimal flicker value, the common voltage value is adjusted based on the detected flicker value. Because the flicker value and common voltage data tables are pre-stored based on rigorous debugging, the actual optimal common voltage value will only deviate from the pre-stored optimal common voltage value when the external environment changes or the hardware ages. The probability of such a deviation is small, so the common voltage value corresponding to the currently detected flicker value is not written into the flicker value and common voltage data tables, but is used directly. Even if the same situation occurs next time, the common voltage value is adjusted again based on the detected flicker value, and the flicker value and common voltage data tables remain unchanged. This keeps the flicker value and common voltage data tables generally stable, with minimal adjustments, which promotes more stable operation of the display device. This design is more suitable for newer equipment, relatively stable hardware, and relatively stable hardware. In these cases, the flicker value and common voltage values ​​are more likely to be affected by changes in the external environment, which are more accidental. Therefore, it is recommended to make judgments based on the detected flicker value each time, and directly use the data in the flicker value and common voltage data tables or adjust the common voltage based on the detected flicker value.

[0086] The following will be explained using a 60hz display panel as an example. The display panel is detected to enter the variable refresh rate mode. By detecting the duration of the vertical blanking period of the current frame, the refresh rate of the current frame is obtained to be 60hz. The flicker value and common voltage data table corresponding to 60hz is called, and the common voltage value corresponding to the minimum flicker value in the flicker value and common voltage data table is selected as the common voltage when the display panel is driven for the next frame. The common voltage value corresponding to the flicker value a is z, and the common voltage value z is called as the common voltage when the display panel is driven for the next frame. The flicker value is detected again. In the flicker value detection, it is found that the actual flicker value is greater than a, and the actual flicker value is at b. The flicker value and the common voltage value corresponding to the flicker value b recorded in the common voltage data table are y. When the actual common voltage value is y, the common voltage value is adjusted according to the detected flicker value b, and adjusted to z+(zy) so that the flicker value is at a. At this time, the adjusted common voltage value z+(zy) is written into the flicker value and common voltage data table corresponding to the current refresh rate, and the common voltage value corresponding to the flicker value a is recorded as z+(zy); it should be noted that the above is only an example, and the actual application is not limited to this. The designer can adjust the common voltage value according to actual needs and then test again whether the flicker value meets the requirements. If it does not meet the requirements, the adjustment can be continued, which can be gradually increasing the common voltage value or gradually decreasing the common voltage value to obtain the public voltage value corresponding to the optimal flicker value. This is not limited here.

[0087] As a further limitation of the above embodiment, after the common voltage value is adjusted according to the current refresh rate, when the flicker value detected again exceeds the preset threshold value, a re-test mark is added to the flicker value and common voltage data table used at this time, and the common voltage value adjusted according to the detected flicker value is recorded in the flicker value and common voltage data table; when the refresh rate same as the current refresh rate is detected again, the corresponding flicker value and the re-test mark in the common voltage data table are read, and after the common voltage value is adjusted according to the detected refresh rate, the flicker value is directly tested because the re-test mark is read, and the flicker value that needs to be adjusted is determined according to the detected flicker value. Common voltage value; in this way, when the flicker value corresponding to the detected refresh rate and the common voltage data table have a retest mark, it can be directly determined that the flicker value and the data in the common voltage data table are not sufficient to adjust the flicker value to the optimal value. After the common voltage value is preliminarily adjusted, the flicker value can be directly detected to obtain the optimal common voltage value based on the detected flicker value, so as to adjust the flicker value to the optimal value, thereby avoiding the inability to adjust the flicker value to the optimal value based on the flicker value and the common voltage data table due to other factors such as aging. In addition, this design also enables the display panel to adjust the common voltage according to actual conditions to adjust the flicker value;

[0088] Among them, the inventor took into account the problem that the detected flicker value may result in detection errors due to other reasons. After determining the common voltage value that needs to be adjusted based on the detected flicker value, the common voltage value determined this time is compared with the common voltage value adjusted according to the last detected flicker value. If the difference between the two common voltage values ​​is less than 5%, the average of the two common voltage values ​​is taken as the new common voltage value for adjustment; if the difference between the two common voltage values ​​is greater than 5%, the common voltage value determined this time is taken for adjustment; with this design, when the difference between the two common voltage values ​​is less than 5%, it means that an error may occur in the flicker value detection, so the average of the two common voltage values ​​can be taken as the new common voltage value for adjustment, thereby minimizing adjustment errors caused by detection errors as much as possible; when the difference between the two common voltage values ​​is greater than 5%, it means that the situations or environments that the two detections may face may have changed greatly, and the common voltage value determined this time is used for adjustment, so that the current optimal common voltage value that is closer to the actual one can be obtained as much as possible for supply work. In this way, it is possible to avoid the common voltage value adjusted according to the detected flicker value failing to adjust the flicker value to the optimal value in the current environment or situation, thereby minimizing adjustment errors caused by detection errors.

[0089] This situation is more suitable for use in situations where the machine is aging or the hardware is unstable, because after aging or hardware instability, this instability is normal, that is, the situations before and after are similar. Therefore, the common voltage value adjusted according to the detected flicker value is recorded in the flicker value and common voltage data table, which is convenient for direct use next time, improving the efficiency of common voltage adjustment and the stability of display device operation. Of course, this design for situations where the machine is aging or the hardware is unstable can also be used in conjunction with the aforementioned design suitable for situations where the device is newer, the hardware is not aged, and the hardware is relatively stable in a display device. In this way, when the device is newer, the hardware is not aged, and the hardware is relatively stable, the aforementioned flicker value and common voltage data table calling strategy is used. When the machine is aging or the hardware is unstable, the current flicker value and common voltage data table calling strategy is used. This combination allows the device to select the best mode according to the actual situation, which is more conducive to efficient and stable display of the display device.

[0090] As a further limitation of the above embodiment, the above step S3 includes:

[0091] S30: Output the common voltage value to the power management integrated circuit;

[0092] S31: During the vertical blanking period of the next frame, the power management integrated circuit outputs the corresponding common voltage to the display panel;

[0093] The common voltage is output to the display panel during the vertical blanking period to avoid abnormal images on the display panel caused by outputting the common voltage during the display phase.

[0094] The following describes how to obtain the flicker value and common voltage data table. The flicker value and common voltage data table in this embodiment are obtained by testing according to the following steps:

[0095] Output test video to the display panel;

[0096] Specifically, the test video is a video with a specific flickering picture, or may be a special slow-motion video, which displays a flickering image of the display panel through the specific flickering picture, so as to record the flicker value and common voltage when the display panel displays the specific flickering picture.

[0097] Get the current refresh rate of the display panel based on the output test video;

[0098] Specifically, the test video is transmitted to the conversion module to convert the video signal of the test video into a digital signal, and then the digital signal is transmitted to the time difference calculation module to convert it into a time difference signal to calculate the current refresh rate of the display panel. For example, for a display panel with a refresh rate of 60hz, the time of one frame is 1 / 60=0.0167s, and the response time is 16.7ms. The current refresh rate value of the display panel can be calculated based on this data to know whether the display panel is adjusted to the refresh rate value to be tested.

[0099] Play the test video, capture the display panel image, and record the flicker value and common voltage of the display panel at the current refresh rate;

[0100] Specifically, the flicker value and the common voltage value can be obtained through an optical measurement program and a multimeter.

[0101] Switch to different common voltages and play test videos multiple times to create a data table of flicker values ​​and common voltages at the current refresh rate.

[0102] Specifically, keep the display panel at the same refresh rate, switch different common voltages, and record the size of the flicker value that appears at different common voltages to obtain the value of the flicker value and common voltage data table at the current refresh rate; it should be noted that the tester can choose the number of data recorded in a flicker value and common voltage data table according to actual needs.

[0103] After switching the refresh rate, the above steps are repeated to obtain the flicker value and common voltage data table at the switched refresh rate, thereby establishing multiple flicker value and common voltage data tables, each corresponding to a different refresh rate, so as to obtain data when adjusting the common voltage.

[0104] like Figure 3 As shown, as a second embodiment of the present application, a common voltage regulation circuit is disclosed, which is applied to the common voltage regulation method described in the above embodiment. The common voltage regulation circuit includes a first detection module, a second detection module, a third detection module, a storage module and a control module. The first detection module detects whether the display panel enters the variable refresh rate mode, the second detection module detects the refresh rate of the display panel, the third detection module detects the flicker value of the display panel, and the storage module stores multiple common voltage values. The control module is electrically connected to the first detection module, the second detection module, the third detection module and the storage module. In this embodiment, the third detection module can be a photosensitive unit, which senses the luminous brightness of the display panel to obtain the flicker value of the display panel. The photosensitive unit includes a photosensitive transistor. After receiving light, the photosensitive transistor can convert the light signal into a current signal. The current value of the current signal sensed by the photosensitive transistor is proportional to the luminous brightness of the display panel and changes accordingly with the change of the luminous brightness. Therefore, the flicker value of the display panel can be obtained through the current signal detected by the photosensitive unit.

[0105] When the first detection module detects that the display panel enters the variable refresh rate mode, the second detection module detects the refresh rate of the display panel, and the control module calls the corresponding common voltage value stored in the storage module according to the refresh rate detected by the second detection module and outputs it to the display panel. The third detection module detects the flicker value of the display panel, and the control module determines whether to adjust the common voltage value according to the flicker value detected by the third detection module. If the detected flicker value does not exceed the preset threshold, it is determined that no adjustment is required. If the detected flicker value exceeds the preset threshold, it is determined that adjustment is required. The control module obtains the corresponding common voltage according to the flicker value and adjusts the output to drive the display panel.

[0106] like Figure 4 As shown, as the third embodiment of the present application, a display device is disclosed, which includes a display panel and a common voltage regulation circuit as described in the above embodiment, and the common voltage regulation circuit is configured to execute the common voltage regulation method as described in the above embodiment. The display device can adjust the common voltage for driving the display panel according to the refresh rate change, and can detect in real time whether the flicker value reaches a preset threshold after the adjustment, and continue to adjust according to the judgment conditions, and adjust the common voltage in real time to make the flicker value of the display device reach the best, thereby improving the user experience.

[0107] It should be noted that the limitations on the steps involved in this solution do not limit the order of the steps without affecting the implementation of the specific solution. The steps written in front can be executed first, later, or even simultaneously. As long as this solution can be implemented, it should be deemed to fall within the scope of protection of this application.

[0108] The technical solution of the present application can be widely used in various display panels, such as TN (Twisted Nematic) display panels, IPS (In-Plane Switching) display panels, VA (Vertical Alignment) display panels, MVA (Multi-Domain Vertical Alignment) display panels. Of course, other types of display panels, such as OLED (Organic Light-Emitting Diode) display panels, can all be applicable to the above solution.

[0109] It should be noted that the inventive concept of this application can form a large number of embodiments, but the length of the application document is limited and it is impossible to list them one by one. Therefore, under the premise of no conflict, the various embodiments or technical features described above can be arbitrarily combined to form new embodiments. After the various embodiments or technical features are combined, the original technical effects will be enhanced.

[0110] The above content is a further detailed description of the present application in conjunction with specific optional implementation methods, and the specific implementation of the present application cannot be considered to be limited to these descriptions. For ordinary technicians in the technical field to which the present application belongs, they can make several simple deductions or substitutions without departing from the concept of the present application, which should be considered to fall within the scope of protection of the present application.

Claims

1. A common voltage regulation method, characterized in that: Including steps: S1: The display panel enters variable refresh rate mode; S2: Get the refresh rate of the current frame, and get the corresponding common voltage value according to the refresh rate of the current frame; S3: output common voltage value to drive the display panel; S4: Detecting a flicker value of the display panel and evaluating the flicker value. If the flicker value is within a preset threshold, repeating step S2 until the display panel exits the variable refresh rate mode. If the flicker value exceeds the preset threshold, the corresponding common voltage is obtained according to the flicker value and adjusted, and step S4 is executed again; Wherein, the preset threshold is a partial flicker value at the current frame refresh rate; If the detected flicker value exceeds a preset threshold, the common voltage value is adjusted according to the detected flicker value, and the common voltage value is written into the flicker value and common voltage data table corresponding to the refresh rate of the current frame, or is directly used without recording; Among them, after the common voltage value is adjusted according to the detected flicker value, the common voltage value determined this time is compared with the common voltage value adjusted according to the detected flicker value last time. If the difference between the two common voltage values ​​is less than 5%, the average value of the two common voltage values ​​is taken as the new common voltage value for adjustment; if the difference between the two common voltage values ​​is greater than 5%, the common voltage value determined this time is taken for adjustment.

2. The common voltage regulation method according to claim 1, characterized in that: The step S2 comprises: S20: Obtaining the refresh rate of the current frame according to the duration of the vertical blanking period of the current frame; S21: According to the refresh rate of the current frame, calling the pre-stored flicker value and common voltage data table to obtain the optimal common voltage value corresponding to the current frame refresh rate; There are a plurality of flicker value and common voltage data tables, each of which has a plurality of groups of data, and each group of data corresponds to a flicker value and a common voltage value associated with the flicker value.

3. The common voltage regulation method according to claim 2, wherein: The flicker value and common voltage data table are obtained by testing through the following steps: Output test video to the display panel; Get the current refresh rate of the display panel based on the output test video; Play the test video, capture the display panel image, and record the flicker value and common voltage of the display panel at the current refresh rate; Switch to different common voltages and play test videos multiple times to create a data table of flicker values ​​and common voltages at the current refresh rate. After the refresh rate is switched, the above steps are repeated to obtain a flicker value and a common voltage data table under the refresh rate after switching.

4. The common voltage regulation method according to claim 3, wherein: The obtaining of the current refresh rate of the display panel according to the output test video includes: Transmitting the test video to the conversion module to convert it into a digital signal; The digital signal is transmitted to the time difference calculation module to be converted into a time difference signal, and the current refresh rate of the display panel is calculated.

5. The common voltage regulation method according to claim 1, wherein: The step S4 comprises: S40: Detecting the display brightness of the display panel within a preset frame number range; S41: Calculate the average display brightness within a preset frame number range to obtain a flicker value; The preset frame number range is between 1 and 10 frames.

6. The common voltage regulation method according to claim 1, wherein: The step S4 further includes: S42: comparing the detected flicker value with a preset threshold at the current refresh rate; S43: If the detected flicker value is within the preset threshold, maintain normal display and repeat step S2 until the display panel exits the variable refresh rate mode; if the detected flicker value exceeds the preset threshold, adjust the common voltage value according to the detected flicker value; S44: Output the adjusted common voltage value to the display panel, and then jump to step S40; When the detected flicker value exceeds a preset threshold, the common voltage value is adjusted according to the detected flicker value through the flicker value and the common voltage data table.

7. The common voltage regulation method according to claim 6, characterized in that: The steps between step S43 and step S44 also include: S431: Writing the adjusted common voltage value into the corresponding flicker value and common voltage data table as new data.

8. The common voltage regulation method according to claim 1, wherein: The step S3 comprises: S30: Output the common voltage value to the power management integrated circuit; S31: During the vertical blanking period of the next frame, the power management integrated circuit outputs the corresponding common voltage to the display panel.

9. A common voltage regulating circuit, applied to the common voltage regulating method according to any one of claims 1 to 8, characterized in that: include: A first detection module detects whether the display panel enters a variable refresh rate mode; A second detection module detects the refresh rate of the display panel; A third detection module detects a flicker value of the display panel; A storage module, storing multiple common voltage values; as well as a control module electrically connected to the first detection module, the second detection module, the third detection module, and the storage module; wherein, when the first detection module detects that the display panel enters the variable refresh rate mode, the second detection module detects the refresh rate of the display panel, the control module calls the corresponding common voltage value stored in the storage module according to the refresh rate detected by the second detection module and outputs it to the display panel, the third detection module detects the flicker value of the display panel, and the control module determines whether to adjust the common voltage value according to the flicker value detected by the third detection module; If the flicker value does not exceed the preset threshold, it is determined that no adjustment is required; if the flicker value exceeds the preset threshold, it is determined that adjustment is required, and the control module obtains the corresponding common voltage according to the flicker value and adjusts the output to drive the display panel; Among them, after the common voltage value is adjusted according to the detected flicker value, the common voltage value determined this time is compared with the common voltage value adjusted according to the detected flicker value last time. If the difference between the two common voltage values ​​is less than 5%, the average value of the two common voltage values ​​is taken as the new common voltage value for adjustment; if the difference between the two common voltage values ​​is greater than 5%, the common voltage value determined this time is taken for adjustment.

10. A display device, characterized in that: The device comprises a display panel and the common voltage regulating circuit according to claim 9, wherein the common voltage regulating circuit is configured to execute the common voltage regulating method according to any one of claims 1 to 8.

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