Gamma voltage adjustment method, gamma voltage adjustment circuit and display device

Abstract

The present application discloses a gamma voltage adjustment method, a gamma voltage adjustment circuit and a display device. The gamma voltage adjustment method is used for displaying a picture after entering a variable refresh rate mode, and includes the following steps: when displaying the current frame, pre-storing the original driving data of the next frame, and calculating the refresh rate of the next frame; obtaining the target refresh rate in the variable refresh rate mode; obtaining the gamma compensation voltage corresponding to the next frame refresh rate; calculating the gamma driving voltage of the next frame according to the gamma compensation voltage and the gamma reference voltage of the next frame, and writing the compensated gamma driving voltage in the vertical blanking period of the current frame to drive the display of the next frame of the display panel. Under the same gray scale, the gamma driving voltage compensated by the gamma compensation voltage makes the brightness of the next frame refresh rate consistent with the brightness of the target refresh rate, thereby improving the problem of large brightness difference or flickering when the display panel displays at different refresh rates.

Description

Technical Field

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

[0002] Conventional display panels (e.g., cathode ray tube (CRT) display panels, liquid crystal display panels (LCD), light emitting diode (LED) display panels, organic light emitting diode (OLED) display panels, active matrix organic light emitting diode (AMOLED) display panels, etc.) operate at a fixed refresh rate, such as 60 Hz, 85 Hz, or 120 Hz. In other words, the display panel is configured to refresh each pixel of the screen at a specific frequency. In conventional systems, the video signal transmitted to the display panel must match the fixed frequency of the refresh rate of the display panel.

[0003] In recent years, the booming e-sports market has allowed many hardware manufacturers to see business opportunities, resulting in more and more diversified choices of monitors. However, the refresh rate of game screens in the e-sports market changes very quickly, with obvious image tearing and fluctuations. The brightness of the display panel varies greatly when switching between different refresh rates, and flickering problems often occur, resulting in a decrease in gaming experience. Summary of the invention

[0004] The purpose of the present application is to provide a gamma voltage adjustment method, a gamma voltage adjustment circuit and a display device, which compensate and adjust the gamma voltage of the next frame in advance to ensure that the brightness remains unchanged when the refresh rate is switched, so as to improve the problem of large brightness difference of the display panel at different refresh frequencies or flickering of the display, and improve the display effect.

[0005] The present application discloses a gamma voltage adjustment method for displaying a picture after entering a variable refresh rate mode, comprising the steps of:

[0006] When the current frame is displayed, the original drive data of the next frame is stored in advance, and the refresh rate of the next frame is calculated; the target refresh rate in the variable refresh rate mode is obtained;

[0007] According to the refresh rate of the next frame and the target refresh rate, a gamma compensation voltage corresponding to the refresh rate of the next frame is obtained;

[0008] Calculating the gamma driving voltage of the next frame according to the gamma compensation voltage and the gamma reference voltage of the next frame, and writing the compensated gamma driving voltage in the vertical blanking period of the current frame to drive the display panel to display the next frame;

[0009] Wherein, under the same gray scale, the gamma driving voltage compensated by the gamma compensation voltage makes the brightness of the next frame refresh rate consistent with the brightness of the target refresh rate.

[0010] Optionally, when the current frame is displayed, the original driving data of the next frame is pre-stored, and the refresh rate of the next frame is calculated; the step of obtaining the target refresh rate in the variable refresh rate mode includes:

[0011] Pre-store the original driving data of N frames after the current frame, calculate the refresh rate of the N frames, arrange the sizes of the refresh rates of the N frames, and select the median refresh rate as the target refresh rate.

[0012] Optionally, the voltage value of the gamma compensation voltage is GAMMA compensation, the gamma voltage value corresponding to the brightness difference between the refresh rate of the next frame and the target refresh rate at the same grayscale is GAMMA difference, and the leakage voltage value in the vertical blanking period of the current frame is GAMMA leakage;

[0013] Among them, GAMMA complement = GAMMA difference + GAMMA leakage;

[0014] The gamma compensation voltage value corresponding to different refresh rates is different; the leakage voltage value of a low refresh rate is greater than the leakage voltage value of a high refresh rate.

[0015] Optionally, the leakage voltage value in the vertical blanking period of the current frame is equal to the sum of the voltage value of the leakage voltage of the thin film transistor corresponding to the pixel of the current frame and the voltage value of the leakage voltage generated by the parasitic capacitor.

[0016] Optionally, the gamma adjustment method further comprises the steps of:

[0017] Get the refresh rate of the previous frame before entering variable refresh rate mode and cache it as the target refresh rate.

[0018] Optionally, the target refresh rate value is greater than or equal to 48 Hz and less than or equal to 144 Hz, and the target refresh rate value is greater than the current frame refresh rate value and less than the next frame refresh rate value.

[0019] Optionally, when the current frame is displayed, the original driving data of the next frame is pre-stored, and the refresh rate of the next frame is calculated; the step of obtaining the target refresh rate in the variable refresh rate mode includes:

[0020] When the current frame is displayed, the original drive data of the next frame and the next frame are stored in advance, and the refresh rates of the next frame and the next frame are calculated; the target refresh rate in the variable refresh rate mode is obtained;

[0021] The step of obtaining the gamma compensation voltage corresponding to the next frame refresh rate according to the next frame refresh rate and the target refresh rate includes:

[0022] According to the refresh rate of the next frame and the target refresh rate, a gamma compensation voltage corresponding to the refresh rate of the next frame is obtained; according to the refresh rate of the next next frame and the target refresh rate, a gamma compensation voltage corresponding to the refresh rate of the next next frame is obtained;

[0023] The step of calculating the gamma driving voltage of the next frame according to the gamma compensation voltage and the gamma reference voltage of the next frame, and writing the compensated gamma driving voltage in the vertical blanking period of the current frame to drive the display panel to display the next frame includes:

[0024] Determine the size of the gamma compensation voltage corresponding to the next frame and the next next frame, select the smaller gamma compensation voltage corresponding to the next frame and the next next frame as the gamma compensation voltage, and calculate the gamma drive voltage of the next frame according to the corresponding gamma reference voltage, and write the compensated gamma drive voltage in the vertical blanking period of the current frame to drive the display panel to display the next frame.

[0025] Optionally, the step of calculating the gamma driving voltage of the next frame according to the gamma compensation voltage and the gamma reference voltage of the next frame, and writing the compensated gamma driving voltage in the vertical blanking period of the current frame to drive the display panel to display the next frame includes:

[0026] When the current frame enters the vertical blanking period, a preset common voltage is used for driving;

[0027] The preset common voltage is greater than the common voltage in the display stage.

[0028] The present application also discloses a gamma voltage adjustment circuit, which is adjusted using any of the gamma adjustment methods described above, and the gamma voltage adjustment circuit includes a detection module, a storage module, a compensation voltage acquisition module and a timing control module; the detection module detects whether the display panel enters the variable refresh rate mode; the storage module stores the original driving data of the next frame and the gamma compensation voltage corresponding to the refresh rate; the compensation voltage acquisition module is electrically connected to the detection module and the storage module; the timing control module is electrically connected to the compensation voltage acquisition module; wherein, when the detection module detects that the display panel enters the variable refresh rate mode, the compensation voltage acquisition module obtains the gamma compensation voltage corresponding to the refresh rate of the next frame according to the refresh rate of the next frame and the target refresh rate and outputs it to the timing control module, and the timing control module calculates the gamma drive voltage according to the gamma compensation voltage and the gamma reference voltage of the next frame to drive the display of the next frame of the display panel; under the same gray scale, the gamma drive voltage compensated by the gamma compensation voltage makes the brightness of the next frame refresh rate consistent with the brightness of the target refresh rate.

[0029] The present application also discloses a display device, including a display panel and any of the gamma voltage adjustment circuits described above, wherein the gamma voltage adjustment circuit uses any of the gamma voltage adjustment methods described above to adjust the gamma driving voltage of the display panel to drive the display panel.

[0030] The gamma voltage adjustment method provided in the present application is used for picture display after entering the variable refresh rate mode. In the variable refresh rate mode, before the refresh rate is frequently switched, when the current frame is displayed, the original driving data of the next frame is pre-stored, the refresh rate of the next frame is calculated and the target refresh rate is set, and the gamma compensation voltage corresponding to the refresh rate of the next frame is obtained; according to the gamma compensation voltage and the gamma reference voltage of the next frame, the gamma driving voltage of the next frame is calculated, and the compensated gamma driving voltage is written in the vertical blanking period of the current frame to drive the display of the next frame of the display panel to perform brightness correction on the display panel, and in the same In grayscale, the gamma driving voltage compensated by the gamma compensation voltage makes the brightness of the next frame refresh rate consistent with the brightness of the target refresh rate. Therefore, even if the refresh rate of the display panel keeps changing, the gamma driving voltage of the next frame is calculated in advance, and the display is driven directly by the gamma driving voltage calculated in advance when the next frame is displayed. The display panel maintains the same display brightness when the refresh rate keeps changing, thereby improving the problem of large brightness difference or flickering of the display panel at different refresh frequencies, solving image tearing and fluctuations, improving the smoothness of the game experience, and bringing users a better gaming experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] 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 ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0032] Figure 1 is a flow chart of a gamma voltage adjustment method according to the first embodiment of the present application;

[0033] Figure 2 is a flow chart of a gamma voltage adjustment method according to the second embodiment of the present application;

[0034] Figure 3 is a flow chart of a gamma voltage adjustment method according to the third embodiment of the present application;

[0035] Figure 4 is a structural schematic diagram of a gamma voltage adjustment circuit according to a fourth embodiment of the present application;

[0036] Figure 5 It is a structural schematic diagram of a display device of the fifth embodiment of the present application.

[0037] Among them, 100, display device; 110, main board; 200, display panel; 300, gamma voltage adjustment circuit; 310, detection module; 320, storage module; 321, storage table; 330, compensation voltage acquisition module; 340, timing control module; 341, micro control unit. DETAILED DESCRIPTION

[0038] 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, but the present application can be implemented in many alternative forms and should not be construed as being limited to only the embodiments described herein.

[0039] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating relative importance or implicitly indicating the number of technical features indicated. Therefore, unless otherwise specified, features defined as "first" and "second" may explicitly or implicitly include one or more of the features; "plurality" means two or more. The term "including" and any variation thereof means non-exclusive inclusion, and one or more other features, integers, steps, operations, units, components and / or combinations thereof may exist or be added.

[0040] 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 and are merely simplified descriptions for the convenience of describing the present application. They do not indicate that the devices or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limitations on the present application.

[0041] In addition, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be internally connected between two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0042] 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.

[0043] like Figure 1 As shown, as a first embodiment of the present application, a gamma voltage adjustment method is disclosed for displaying a picture after entering a variable refresh rate mode, comprising the steps of:

[0044] S1: When the current frame is displayed, the original drive data of the next frame is stored in advance, the refresh rate of the next frame is calculated, and the target refresh rate in the variable refresh rate mode is obtained;

[0045] S2: Obtaining a gamma compensation voltage corresponding to the next frame refresh rate according to the next frame refresh rate and the target refresh rate;

[0046] S3: calculating the gamma driving voltage of the next frame according to the gamma compensation voltage and the gamma reference voltage of the next frame, and writing the compensated gamma driving voltage in the vertical blanking period of the current frame to drive the display panel to display the next frame;

[0047] Wherein, under the same gray scale, the gamma driving voltage compensated by the gamma compensation voltage makes the brightness of the next frame refresh rate consistent with the brightness of the target refresh rate.

[0048] Since large brightness differences or display flickering problems are prone to occur when the refresh rate changes, an embodiment of the present invention provides a gamma voltage adjustment method, which sets a target refresh rate and obtains a gamma compensation voltage corresponding to the next frame refresh rate; calculates the gamma drive voltage of the next frame according to the gamma compensation voltage and the gamma reference voltage of the next frame, and writes the compensated gamma drive voltage in the vertical blanking period of the current frame to drive the display of the next frame of the display panel to perform brightness correction on the display panel. Under the same gray scale, the gamma drive voltage compensated by the gamma compensation voltage makes the brightness of the next frame refresh rate consistent with the brightness of the target refresh rate, even in the variable refresh rate mode, the brightness of the display panel can be consistent or nearly consistent when the refresh rate changes, and when the refresh rate changes, the gamma drive voltage generated according to the gamma compensation voltage can take effect in real time, so that the brightness difference when the refresh rate changes is not obvious due to the short time, making it difficult for the human eye to perceive the flicker phenomenon, thereby improving the display effect of the display panel.

[0049] To sum up, after entering the variable refresh rate mode, the first frame should be displayed in the first frame cycle, the original drive data of the second frame should be cached, and the gamma compensation voltage value of the second frame should be calculated; the second frame should be displayed in the second frame cycle, the original drive data of the third frame should be cached, and the gamma compensation voltage value of the third frame should be calculated, and so on.

[0050] In addition, the selection of the target refresh rate is also very important. The brightness of the target refresh rate determines the difference in the compensation value selected for each frame refresh rate. Generally, the target refresh rate can be selected as 48Hz or 144Hz. Using the current highest refresh rate or lowest refresh rate as the target refresh rate can help find the compensation value corresponding to the next frame refresh more quickly.

[0051] The brightness of the target refresh rate is used as the fixed brightness, and the gamma compensation voltage is adjusted to make the display brightness at different refresh rates close to the display brightness of the target refresh rate, wherein the target refresh rate is preferably a high refresh rate, such as any value between 100 Hz and 144 Hz, so that the display brightness of the display device applying the gamma voltage adjustment method is brighter and the display effect of the display device is better. Of course, it can also be set according to actual conditions. For example, if the display device using the gamma voltage adjustment method needs to achieve a low power consumption function, the target refresh rate is preferably a low refresh rate, such as any value between 44 Hz and 60 Hz. Of course, any value between 48 Hz and 144 Hz can also be selected. In order to facilitate table lookup to obtain the compensation value of the next frame refresh rate, the value of the target refresh rate is set to be greater than the current frame refresh rate and less than the next frame refresh rate.

[0052] Of course, you can also use the frame before entering the variable refresh rate mode as the target refresh rate. Before and after entering the variable refresh rate mode, the brightness remains consistent, there will be no change in brightness, and the picture will be smoother.

[0053] It should be noted that the current frame and the next frame correspond to different cycles. The cycle of each frame includes a display phase (Vactive) and a vertical blanking period (Vblank). The duration of the display phase and the duration of the vertical blanking period are different under different refresh rates.

[0054] Since the length of the vertical blanking period under different refresh rates is different, the leakage current generated is also different. As the second embodiment of the present application, on the basis of considering the brightness compensation to set the gamma compensation voltage, the leakage voltage conditions at different refresh rates are also considered and combined into the gamma compensation voltage to improve the accuracy of the gamma compensation voltage.

[0055] The voltage value of the gamma compensation voltage is GAMMA compensation, the gamma voltage value corresponding to the brightness difference between the refresh rate of the next frame and the target refresh rate at the same gray scale is GAMMA difference, and the leakage voltage value in the vertical blanking period of the current frame is GAMMA leakage;

[0056] Among them, GAMMA complement = GAMMA difference + GAMMA leakage;

[0057] The gamma compensation voltage value corresponding to different refresh rates is different; the leakage voltage value of a low refresh rate is greater than the leakage voltage value of a high refresh rate.

[0058] Furthermore, it should be noted that the leakage voltage value in the vertical blanking period of the current frame is equal to the sum of the voltage value of the leakage voltage of the thin film transistor corresponding to the pixel of the current frame and the voltage value of the leakage voltage generated by the parasitic capacitance. The gamma compensation voltage of the present application takes into account the leakage voltage generated by the thin film transistor in the pixel, as well as the leakage voltage caused by the parasitic capacitance generated between the pixel electrode and the data line and the scanning line, thereby ensuring the accuracy of the gamma compensation voltage.

[0059] like Figure 2 As shown, as the second embodiment of the present application, different from the above embodiment, step S1 includes:

[0060] S1': when the current frame is displayed, the original driving data of the next frame and the next frame are stored in advance, and the refresh rates of the next frame and the next frame are calculated; the target refresh rate in the variable refresh rate mode is obtained;

[0061] The S2 step includes:

[0062] S2': according to the refresh rate of the next frame and the target refresh rate, obtain the gamma compensation voltage corresponding to the refresh rate of the next frame; according to the refresh rate of the next next frame and the target refresh rate, obtain the gamma compensation voltage corresponding to the refresh rate of the next next frame; (the next next frame: the next frame of the next frame)

[0063] The S3 steps include:

[0064] S3': Determine the size of the gamma compensation voltage corresponding to the next frame and the next next frame, select the smaller gamma compensation voltage corresponding to the next frame and the next next frame as the gamma compensation voltage, and calculate the gamma drive voltage of the next frame according to the corresponding gamma reference voltage, and write the compensated gamma drive voltage in the vertical blanking period of the current frame to drive the display panel to display the next frame.

[0065] When the current frame is displayed, the original driving data of two frames are pre-stored to obtain the refresh rate of the next two frames. When the refresh of the next two frames is known, the gamma compensation voltage corresponding to the refresh rate of the next two frames can be known. Since the adjustment of the gamma compensation voltage is also adjusted according to the brightness of the target refresh rate, after obtaining the target refresh rate in the variable refresh rate mode, the gamma compensation voltage of the refresh rate that is closer to the target refresh rate is selected for compensation according to the brightness value of the target refresh rate. The target refresh rate is set to a value between the refresh rates of the two frames. When compensating, the adjusted gamma compensation voltage range is smaller, which further saves power consumption.

[0066] In addition, when the current frame is displayed, the original driving data of N frames after the current frame is pre-stored, the refresh rate of the N frames is calculated, the refresh rates of the N frames are arranged, and the median refresh rate is selected as the target refresh rate. In this way, when the picture is displayed in the variable refresh rate mode, since the refresh rate of most frames is close to the target refresh rate, the brightness compensation can be completed more quickly, ensuring that the picture brightness changes little when the refresh rate is switched in the entire variable refresh rate mode, and the picture is smoother.

[0067] Taking N equals 5 as an example, the original drive data of the next 5 frames of the current frame is pre-stored, and the refresh rate of the next 5 frames is calculated based on the original drive data of the next 5 frames. Assuming that the refresh rates of the next 5 frames are 60Hz, 70Hz, 80Hz, 60Hz, and 80Hz, the refresh rates of the next 5 frames are sorted by band, that is, the order is 60Hz, 60Hz, 70Hz, 80Hz, and 80Hz, where 70Hz is the median of the 5-frame refresh rate, and 70Hz is used as the target refresh rate. If N is an even number, any refresh rate of the two medians can be selected as the target refresh rate; of course, the average of all refresh rates can be calculated again, and a median with a smaller difference from the average value can be selected as the target refresh rate. Of course, the refresh rate of the mode value or the average value can also be used as the target refresh rate, and the selection and calculation can be made according to the actual refresh rate of the next N frames to reduce the adjustment range between the target refresh rate and other refresh rates in the variable refresh rate mode.

[0068] like Figure 3 As shown, as the third embodiment of the present application, different from the above-mentioned first embodiment, the step of calculating the gamma driving voltage of the next frame of the picture according to the gamma compensation voltage and the gamma reference voltage of the next frame, and writing the compensated gamma driving voltage in the vertical blanking period of the current frame to drive the display panel to display the next frame of the picture includes:

[0069] S31: calculating the gamma driving voltage of the next frame according to the gamma compensation voltage and the gamma reference voltage of the next frame;

[0070] S32: when the current frame enters the vertical blanking period, the preset common voltage is used for driving, and the compensated gamma driving voltage is written in the vertical blanking period of the current frame to drive the display panel to display the next frame.

[0071] The preset common voltage is greater than the common voltage in the display stage.

[0072] Specifically, when the display panel enters the variable refresh rate mode, when the current frame enters the vertical blanking period, it is driven using the preset color film substrate common voltage (CFvcom); wherein the preset color film substrate common voltage is the common voltage when the display panel is at maximum brightness at 255 grayscales. According to the VT curve characteristics, the transmittance and brightness of the liquid crystal depend on the voltage difference between CFvcom and the gamma drive voltage. The higher the gamma drive voltage, the higher the transmittance of the liquid crystal, and the brighter the brightness. Based on this characteristic, the optimal CFvcom of 255 grayscales is found in the variable refresh rate mode as the CFvcom of the display panel when it enters the variable refresh rate module. When the display panel switches to normal display mode, the CFvcom in normal display mode can be used.

[0073] The display panel has multiple grayscales. Different gamma driving voltages are called to drive the display panel according to different grayscales. After the timing control module generates the gamma driving voltage, the gamma driving voltage is output to the source driver chip (Source-IC), and the gamma circuit inside the source driver chip is combined to generate voltages for all grayscales, and then the sub-gamma driving voltage of the corresponding grayscale is output to drive the display panel.

[0074] Of course, you can also increase Avcom and increase the charge of the storage capacitor Cst to partially offset the leakage. Combined with the gamma compensation voltage, it can better improve the brightness difference or flickering problem of the display panel when switching the refresh rate.

[0075] like Figure 4 As shown, as the fourth embodiment of the present application, the present application also discloses a gamma voltage adjustment circuit 300, which is adjusted using any of the gamma adjustment methods described above, and the gamma voltage adjustment circuit 300 includes a detection module 310, a storage module 320, a compensation voltage acquisition module 330 and a timing control module 340; the compensation voltage acquisition module 330 is electrically connected to the detection module 310 and the storage module 320; the timing control module 340 is electrically connected to the compensation voltage acquisition module 330.

[0076] The detection module 310 detects whether the display panel enters the variable refresh rate mode; the storage module 320 stores the original driving data of the next frame and the gamma compensation voltage corresponding to the refresh rate; wherein, when the detection module 310 detects that the display panel enters the variable refresh rate mode, the compensation voltage acquisition module 330 obtains the gamma compensation voltage corresponding to the refresh rate of the next frame according to the refresh rate of the next frame and the target refresh rate, and outputs it to the timing control module 340; the timing control module 340 calculates the gamma driving voltage according to the gamma compensation voltage and the gamma reference voltage of the next frame to drive the display of the next frame of the display panel; under the same gray scale, the gamma driving voltage compensated by the gamma compensation voltage makes the brightness of the next frame refresh rate consistent with the brightness of the target refresh rate.

[0077] The storage module 320 includes a storage table 321, which obtains the gamma compensation voltage corresponding to the refresh rate by looking up the table. After using the timing control module 340 to detect the refresh rate of the current frame, the corresponding pre-stored gamma compensation voltage is selected according to the difference between the refresh rate of the current frame and the target refresh rate. The gamma compensation voltage is output to the timing control module 340 for use in the display stage of the next frame cycle, thereby realizing brightness correction of the display panel.

[0078] The storage module 320 will store all the picture data of the next frame. When the current frame is displayed, the timing control module 340 can calculate the refresh rate of the next frame according to the picture stored in the storage module 320, and feed back the compensation voltage acquisition module 330. Further, the micro control unit 341 inside the timing control module 340 is used to dynamically adjust the gamma compensation voltage according to the change of the refresh rate of the current frame, and N I2C instructions are issued in the vertical blanking period, that is, the gamma compensation voltage data stored in the micro control unit 341 is transmitted to the compensation voltage acquisition module 330 through the I2C bus, and each An I2C instruction corresponds to a gamma compensation voltage of the same frequency. By outputting N I2C instructions to switch different gamma compensation voltages, the brightness of the current frame refresh rate is close to the brightness of the target refresh rate, so that the display brightness of the display panel remains unchanged or almost the same, thereby improving the problem of large brightness difference of the display panel at different refresh frequencies or display flickering. It should be noted that storing and applying multiple groups of gamma compensation voltage data in the form of I2C instructions reduces the storage amount of data and is also convenient for calling applications, where N is a natural number, and N is greater than or equal to 1.

[0079] like Figure 5As shown, as the fifth embodiment of the present application, a display device 100 is disclosed, wherein the display device 100 includes a display panel 200 and a gamma voltage adjustment circuit 300 as described above, wherein the gamma voltage adjustment circuit 300 uses any of the gamma voltage adjustment methods as described above to adjust the gamma driving voltage of the display panel 200 to drive the display panel 200.

[0080] The detection module 310, the storage module 320, and the compensation voltage acquisition module 330 are arranged in the main board (System on Chip, SOC) of the display device. The storage module 320 reads the front cache and the rear cache to identify the current refresh rate. When the timing control module 340 modifies the next frame data in the gamma chip during the V-blank time of the current frame, when the current frame is displayed, TCON calculates the refresh rate of the current frame, and then feeds it back to the main board, giving an I2C instruction to solve the problem of 1 frame delay caused by the gamma driving voltage taking effect in the next frame.

[0081] In VRR mode, a VGC compensation algorithm is added to the timing control module 340, wherein the VGC compensation algorithm is a corresponding gamma compensation voltage calculated at the same brightness under the same grayscale and different refresh rates; when the timing control module detects a V-blank area, N groups of I2C instructions are added according to the length of the V-blank area, and the GAMMA voltage register address that can identify the gamma chip is added to the corresponding I2C instruction, and after the VGC function is turned on, the GAMMA voltage compensation value of the frequency is called at different frequencies in VRR mode.

[0082] It should be noted that the limitations on the various steps involved in this solution, without affecting the implementation of the specific solution, are not deemed to limit the order of the steps. The steps written in front can be executed first, or 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.

[0083] The technical solution of the present application can be widely used in various display panels, such as TN (Twisted Nematic) display panel, IPS (In-Plane Switching) display panel, VA (Vertical Alignment) display panel, MVA (Multi-Domain Vertical Alignment) display panel, and of course, other types of display panels, such as OLED (Organic Light-Emitting Diode) display panel, can all be applicable to the above solution.

[0084] It should be noted that the inventive concept of the present 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 embodiments or technical features described above can be arbitrarily combined to form new embodiments. After the embodiments or technical features are combined, the original technical effects will be enhanced.

[0085] The above content is a further detailed description of the present application in combination with specific optional implementation methods, and it cannot be determined that the specific implementation of the present application is limited to these descriptions. For ordinary technicians in the technical field to which the present application belongs, several simple deductions or substitutions can be made without departing from the concept of the present application, which should be deemed to fall within the scope of protection of the present application.

Claims

1. A gamma voltage adjustment method for displaying a picture after entering a variable refresh rate mode, characterized in that: Includes steps: When the current frame is displayed, the original drive data of the next frame is stored in advance and the refresh rate of the next frame is calculated; Get the target refresh rate in variable refresh rate mode; According to the refresh rate of the next frame and the target refresh rate, a gamma compensation voltage corresponding to the refresh rate of the next frame is obtained; Calculating the gamma driving voltage of the next frame according to the gamma compensation voltage and the gamma reference voltage of the next frame, and writing the compensated gamma driving voltage in the vertical blanking period of the current frame to drive the display panel to display the next frame; Wherein, under the same gray scale, the gamma driving voltage compensated by the gamma compensation voltage makes the brightness of the next frame refresh rate consistent with the brightness of the target refresh rate; When the current frame is displayed, the original drive data of the next frame is pre-stored, and the refresh rate of the next frame is calculated; the step of obtaining the target refresh rate in the variable refresh rate mode includes: When the current frame is displayed, the original drive data of the next frame and the next frame are stored in advance, and the refresh rates of the next frame and the next frame are calculated; the target refresh rate in the variable refresh rate mode is obtained; The step of obtaining the gamma compensation voltage corresponding to the next frame refresh rate according to the next frame refresh rate and the target refresh rate includes: According to the refresh rate of the next frame and the target refresh rate, a gamma compensation voltage corresponding to the refresh rate of the next frame is obtained; according to the refresh rate of the next next frame and the target refresh rate, a gamma compensation voltage corresponding to the refresh rate of the next next frame is obtained; The step of calculating the gamma driving voltage of the next frame according to the gamma compensation voltage and the gamma reference voltage of the next frame, and writing the compensated gamma driving voltage in the vertical blanking period of the current frame to drive the display panel to display the next frame includes: Determine the size of the gamma compensation voltage corresponding to the next frame and the next next frame, select the smaller gamma compensation voltage corresponding to the next frame and the next next frame as the gamma compensation voltage, and calculate the gamma drive voltage of the next frame according to the corresponding gamma reference voltage, and write the compensated gamma drive voltage in the vertical blanking period of the current frame to drive the display panel to display the next frame.

2. The gamma voltage adjustment method according to claim 1, characterized in that: When the current frame is displayed, the original drive data of the next frame is pre-stored and the refresh rate of the next frame is calculated; The steps to obtain the target refresh rate in variable refresh rate mode include: Pre-store the original driving data of N frames after the current frame, calculate the refresh rate of the N frames, arrange the sizes of the refresh rates of the N frames, and select the median refresh rate as the target refresh rate.

3. The gamma voltage adjustment method according to claim 1, wherein: The voltage value of the gamma compensation voltage is GAMMA compensation, the gamma voltage value corresponding to the brightness difference between the refresh rate of the next frame and the target refresh rate at the same grayscale is GAMMA difference, and the leakage voltage value in the vertical blanking period of the current frame is GAMMA leakage; Among them, GAMMA complement = GAMMA difference + GAMMA leakage; The gamma compensation voltage value corresponding to different refresh rates is different; the leakage voltage value of a low refresh rate is greater than the leakage voltage value of a high refresh rate.

4. The gamma voltage adjustment method according to claim 3, characterized in that: The leakage voltage value in the vertical blanking period of the current frame is equal to the sum of the voltage value of the leakage voltage of the thin film transistor corresponding to the pixel of the current frame and the voltage value of the leakage voltage generated by the parasitic capacitor.

5. The gamma voltage adjustment method according to claim 1, wherein: The gamma voltage adjustment method further comprises the steps of: Get the refresh rate of the previous frame before entering variable refresh rate mode and cache it as the target refresh rate.

6. The gamma voltage adjustment method according to claim 1, wherein: The target refresh rate is greater than or equal to 48 Hz and less than or equal to 144 Hz, and the target refresh rate is greater than the current frame refresh rate and less than the next frame refresh rate.

7. The gamma voltage adjustment method according to claim 1, characterized in that: The step of calculating the gamma driving voltage of the next frame according to the gamma compensation voltage and the gamma reference voltage of the next frame, and writing the compensated gamma driving voltage in the vertical blanking period of the current frame to drive the display panel to display the next frame includes: When the current frame enters the vertical blanking period, a preset common voltage is used for driving; The preset common voltage is greater than the common voltage of the array substrate in the display stage.

8. A gamma voltage adjustment circuit, using the gamma voltage adjustment method according to any one of claims 1 to 7 for adjustment, characterized in that: include: A detection module, detecting whether the display panel enters a variable refresh rate mode; A storage module stores the original driving data of the next frame and the gamma compensation voltage corresponding to the refresh rate; A compensation voltage acquisition module, electrically connected to the detection module and the storage module; A timing control module, electrically connected to the compensation voltage acquisition module; Wherein, when the detection module detects that the display panel enters the variable refresh rate mode, the compensation voltage acquisition module obtains the gamma compensation voltage corresponding to the refresh rate of the next frame according to the refresh rate of the next frame and the target refresh rate, and outputs it to the timing control module, and the timing control module calculates the gamma drive voltage according to the gamma compensation voltage and the gamma reference voltage of the next frame to drive the display panel to display the next frame of the picture; Under the same gray scale, the gamma driving voltage compensated by the gamma compensation voltage makes the brightness of the next frame refresh rate consistent with the brightness of the target refresh rate.

9. A display device, characterized in that: The invention comprises a display panel and a gamma voltage regulating circuit as claimed in claim 8, wherein the gamma voltage regulating circuit uses a gamma voltage regulating method as claimed in any one of claims 1 to 7 to regulate a gamma driving voltage of the display panel to drive the display panel.

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