Display driving method and display driving chip of display panel, and display device

Abstract

The application discloses a display driving method and a display driving chip and a display device. The display driving method comprises the following steps: obtaining a to-be-displayed gray scale of a sub-pixel in a frame of to-be-displayed picture; judging whether the to-be-displayed gray scale meets a gray scale optimization condition of a gamma curve; if yes, dividing a refresh period of the to-be-displayed picture into a plurality of sub-frames; and controlling the sub-pixel to display a first gray scale based on a first data signal in the refresh period of the to-be-displayed picture, wherein the first gray scale corresponding to at least part of the sub-frames is greater than the to-be-displayed gray scale, the first gray scale corresponding to at least part of the sub-frames is less than the to-be-displayed gray scale, and the first gray scale is not equal to the to-be-displayed gray scale; and the first gray scale and the corresponding first data signal meet the gamma curve.

Description

Technical Field

[0001] This application relates to the field of image display technology, and more specifically, to a display driving method, display driving chip, and display device for a display panel. Background Technology

[0002] With the continuous advancement of science and technology, more and more display devices are being widely used in people's daily lives and work, bringing great convenience to people's daily lives and work, and becoming an indispensable tool in people's lives today.

[0003] The display panel is the main component of a display device that enables its display function. The display panel requires a display driver chip to display images. In related display devices, when the display driver chip controls the display panel to display images, it may be unable to accurately display the brightness of the grayscale levels to be displayed, thus affecting display quality. Summary of the Invention

[0004] In view of this, this application provides a display driving method, display driving chip, and display device for a display panel, as follows:

[0005] A display driving method for a display panel, comprising:

[0006] Obtain the grayscale of a subpixel in a frame to be displayed;

[0007] Determine whether the grayscale to be displayed meets the grayscale optimization conditions of the gamma curve;

[0008] If so, divide the refresh cycle of the screen to be displayed into multiple subframes;

[0009] During the refresh cycle of the screen to be displayed, the first gray level is displayed by controlling the sub-pixels based on the first data signal. The first gray level corresponding to at least some sub-frames is greater than the gray level to be displayed, the first gray level corresponding to at least some sub-frames is less than the gray level to be displayed, and the first gray level is not equal to the gray level to be displayed. The first gray level and the corresponding first data signal satisfy the gamma curve.

[0010] The display driving method provided by this application can divide the refresh cycle of the screen to be displayed into multiple sub-frames when the gray level to be displayed meets the gray level optimization conditions of the gamma curve. During the refresh cycle of the screen to be displayed, based on the first gray level that meets the gamma curve and the corresponding first data signal, the sub-pixels are controlled to display the image in each sub-frame, which can accurately display the brightness of the gray level to be displayed and improve the display quality.

[0011] A display driver chip, comprising:

[0012] The acquisition module is used to acquire the grayscale of a sub-pixel in a frame of the image to be displayed;

[0013] The processing module is used to determine whether the grayscale to be displayed meets the grayscale optimization conditions of the gamma curve; if so, the refresh cycle of the screen to be displayed is divided into multiple sub-frames.

[0014] A driving module is configured to control the sub-pixels to display a first gray level based on a first data signal during the refresh cycle of the screen to be displayed, wherein at least some of the sub-frames correspond to a first gray level that is greater than the gray level to be displayed, at least some of the sub-frames correspond to a first gray level that is less than the gray level to be displayed, and the first gray level is not equal to the gray level to be displayed.

[0015] Wherein, the first gray level and the corresponding first data signal satisfy the gamma curve.

[0016] The display driver chip provided in this application can execute the above-mentioned display driving method, and can control the display panel to display grayscale that cannot be accurately displayed through multiple subframes, thereby improving the display quality.

[0017] A display device includes the aforementioned display driver chip.

[0018] The display device can display grayscale values ​​that cannot be accurately displayed through multiple subframes, thus improving display quality. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this application or related technologies, the drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the drawings described below are only embodiments of this application. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0020] The structures, proportions, sizes, etc., shown in the accompanying drawings are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed in the specification, and are not intended to limit the implementation conditions of this application. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size, without affecting the effects and purposes that this application can produce, should still fall within the scope of the technical content disclosed in this application.

[0021] Figure 1 This is a schematic diagram illustrating the principle of a conventional PWM drive mode.

[0022] Figure 2 This is a schematic diagram illustrating the principle that the required brightness for grayscale cannot be accurately displayed in the conventional PWM drive mode.

[0023] Figure 3 A flowchart illustrating a display driving method provided in an embodiment of this application;

[0024] Figure 4 A flowchart illustrating another display driving method provided in an embodiment of this application;

[0025] Figure 5 A flowchart illustrating a method for determining whether a grayscale level to be displayed and its corresponding data signal to be displayed satisfy a gamma curve, provided in an embodiment of this application.

[0026] Figure 6 A flowchart illustrating yet another display driving method provided in an embodiment of this application;

[0027] Figure 7 A flowchart illustrating yet another display driving method provided in an embodiment of this application;

[0028] Figure 8 A flowchart illustrating yet another display driving method provided in an embodiment of this application;

[0029] Figure 9 A flowchart illustrating yet another display driving method provided in an embodiment of this application;

[0030] Figure 10 A flowchart illustrating a method for dividing a refresh cycle into multiple subframes, as provided in this application embodiment;

[0031] Figure 11 A schematic diagram of a display driver chip provided in an embodiment of this application;

[0032] Figure 12 A schematic diagram of another display driver chip provided in an embodiment of this application;

[0033] Figure 13 A schematic diagram of yet another display driver chip provided in an embodiment of this application;

[0034] Figure 14 A schematic diagram of another display driver chip provided in an embodiment of this application;

[0035] Figure 15 A schematic diagram of another display driver chip provided in an embodiment of this application;

[0036] Figure 16 A schematic diagram of another display driver chip provided in an embodiment of this application;

[0037] Figure 17 A schematic diagram of a processing module provided in an embodiment of this application;

[0038] Figure 18 This is a schematic diagram illustrating the principle of a display driver chip controlling a display panel in accordance with an embodiment of this application.

[0039] Figure 19 An image timing diagram provided for an embodiment of this application;

[0040] Figure 20 Another image timing diagram provided for embodiments of this application;

[0041] Figure 21 This application provides yet another image timing diagram;

[0042] Figure 22 This application provides yet another image timing diagram;

[0043] Figure 23 This is a schematic diagram of the structure of a display device provided in an embodiment of this application. Detailed Implementation

[0044] The embodiments of this application will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0045] Various modifications and variations can be made to this application without departing from its spirit or scope, which will be apparent to those skilled in the art. Therefore, this application is intended to cover modifications and variations falling within the scope of the corresponding claims (the claimed technical solutions) and their equivalents. It should be noted that the embodiments provided in this application can be combined with each other without contradiction.

[0046] PWM (Pulse Width Modulation) driving mode is a commonly used display driving method in the MicroLED field. It can effectively improve LED luminous efficiency and reduce power consumption at low grayscale levels. However, when adjusting gamma in PWM driving mode, grayscale distortion can occur, making it impossible to accurately display the brightness of grayscale levels. This results in the inability to distinguish the brightness of adjacent grayscale levels, affecting display quality.

[0047] In non-PWM drive mode, when controlling sub-pixels to display an image, the refresh cycle of one display frame is directly divided into multiple sub-frames, and each sub-frame is controlled sequentially for image display. Grayscale is related to the drive current; for example, the higher the grayscale, the greater the drive current, and the duration of the illumination phase is the same for different display grayscales. In PWM drive mode, however, the drive current is a PWM signal. In PWM drive mode, the amplitude of the drive current during the illumination phase is the same for sub-frames displaying different grayscales, but the duration of the illumination phase differs. The brightness of the displayed grayscale is determined based on the overall display effect of multiple sub-frames, based on the combined effect of the multiple sub-frames, to display the required grayscale brightness for one refresh cycle.

[0048] refer to Figure 1 As shown, Figure 1 This is a schematic diagram illustrating the principle of a conventional PWM drive mode. Figure 1 A frame F0 is divided into 8 subframes F1. Each subframe F1 includes a data writing phase F11 and a light emission phase F12. The duration of the data writing phase F11 is the same for all subframes F1, while the duration of the light emission phase F12 varies. These 8 subframes are designated as subframe 1 to subframe 8 in chronological order, and the duration of the light emission phase F12 in the i-th subframe is 2 seconds. i-1 T, where i is a positive integer not greater than 8, and T is a set constant. The duration of the emission phase F12 from the 1st to the 8th subframe are 1T / 2T / 4T / 8T / 16T / 32T / 64T / 128T respectively.

[0049] The grayscale displayed in a frame is positively correlated with the total duration of the illumination phase. By controlling the illumination state of subframes 1 to 8, any grayscale level from 0 to 252 can be displayed. If all subframes are illuminated, the total illumination phase duration of a frame is 255T, which can represent 255 grayscale levels; if all subframes are not illuminated, the total illumination phase duration of a frame is 0T, which can represent 0 grayscale levels; if only subframes 1 and 3 are illuminated, the total illumination phase duration of a frame is 5T, which can represent 5 grayscale levels.

[0050] refer to Figure 2 As shown, Figure 2 This is a schematic diagram illustrating the principle that the required brightness for grayscale cannot be accurately displayed in conventional PWM drive mode. Figure 2 The horizontal axis represents grayscale, the vertical axis represents brightness, and the dashed curve represents the gamma curve of the display panel. The actual relationship between displayed grayscale and brightness is as follows: Figure 2 The solid line represents the relationship between grayscale and brightness when a refresh cycle is divided into 8 subframes; the thin line represents the relationship between grayscale and brightness when a refresh cycle is divided into 10 subframes.

[0051] Because the PWM drive mode makes the brightness and the display time of the light emission stage have a linear relationship, while the gamma curve is non-linear, the display grayscale and display brightness cannot accurately correspond to the coordinate information on the gamma curve. As a result, the display panel cannot be accurately driven according to the gamma curve, resulting in display brightness deviation.

[0052] contrast Figure 2 As can be seen from the thin and thick polylines, increasing the number of subframes in the refresh cycle increases the density of the polyline segments representing the actual displayed grayscale and brightness, making the polylines closer to the gamma curve. During display driving, the display panel can be better driven based on the gamma curve, thus resolving the brightness deviation issue. However, if too many subframes are divided into a single refresh cycle, sufficient charging time for each subframe cannot be guaranteed, affecting display brightness.

[0053] In view of this, embodiments of this application provide a display driving method, display driving chip, and display device for a display panel. When the grayscale to be displayed meets the grayscale optimization conditions of the gamma curve, the refresh cycle of the image to be displayed is divided into multiple sub-frames. During the refresh cycle of the image to be displayed, based on the first grayscale that meets the gamma curve and the corresponding first data signal, the sub-pixels are controlled to display images in each sub-frame, which can accurately display the brightness of the grayscale to be displayed and improve the display quality.

[0054] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0055] refer to Figure 3 As shown, Figure 3 This is a flowchart illustrating a display driving method provided in an embodiment of this application. The display driving method includes:

[0056] Step S11: Obtain the grayscale of the sub-pixel in a frame of the image to be displayed.

[0057] Step S12: Determine whether the grayscale to be displayed meets the grayscale optimization conditions of the gamma curve.

[0058] Step S13: If so, divide the refresh cycle of the screen to be displayed into multiple subframes.

[0059] Step S14: During the refresh cycle of the screen to be displayed, the sub-pixels are controlled to display the first gray level based on the first data signal, wherein at least some sub-frames correspond to a first gray level that is greater than the gray level to be displayed, at least some sub-frames correspond to a first gray level that is less than the gray level to be displayed, and the first gray level is not equal to the gray level to be displayed; wherein the first gray level and the corresponding first data signal satisfy the gamma curve.

[0060] When the grayscale to be displayed satisfies the grayscale optimization conditions of the gamma curve, one refresh cycle is divided into multiple (complex) subframes, and display control is performed on each subframe separately. The first grayscale displayed in a subframe and its corresponding first data signal satisfy the gamma curve. Grayscales to be displayed that do not satisfy the gamma curve are equivalently displayed in multiple (complex) subframes using the first grayscale that satisfies the gamma curve and its corresponding first data signal, thus accurately displaying the brightness of the grayscale to be displayed.

[0061] refer to Figure 4 , Figure 4 This is a flowchart illustrating another display driving method provided in an embodiment of this application. Figure 3 Based on the method shown, Figure 4 The display driver method shown also includes:

[0062] Step S15: If the gray level to be displayed does not meet the gray level optimization conditions of the gamma curve, based on the given data signal to be displayed, control the sub-pixels to display the gray level to be displayed during the refresh cycle.

[0063] When the grayscale optimization conditions of the gamma curve are not met, only one display control of the sub-pixel is needed based on the data signal to be displayed during the refresh cycle. There is no need to perform multiple display controls in multiple sub-frames to accurately display the brightness required for the grayscale to be displayed.

[0064] In step S12 above, the method for determining whether the grayscale optimization conditions are met includes: if the grayscale to be displayed and its corresponding data signal to be displayed do not meet the gamma curve, then the grayscale optimization conditions are met; if the grayscale to be displayed and its corresponding data signal to be displayed meet the gamma curve, then the grayscale optimization conditions are not met.

[0065] refer to Figure 5 As shown, Figure 5 A flowchart of a method for determining whether a grayscale level to be displayed and its corresponding data signal satisfy a gamma curve, provided in this application embodiment, is included in the method:

[0066] Step S21: Determine the brightness of the sub-pixel when displaying the grayscale according to the data signal to be displayed, based on the grayscale to be displayed and its corresponding data signal to be displayed.

[0067] For a given display panel, its gamma curve is fixed, and the brightness of the corresponding grayscale value displayed based on the data signal to be displayed is also fixed. The display panel's luminance can be tested beforehand to obtain the brightness of the sub-pixels displaying the grayscale value under the data signal to be displayed.

[0068] Step S22: Determine whether the target coordinates are located on the gamma curve.

[0069] In this table, the horizontal axis of the target coordinates represents the grayscale to be displayed, and the vertical axis represents the brightness of the sub-pixel when it is displayed based on the grayscale to be displayed.

[0070] Step S23: If so, determine that the grayscale to be displayed and its corresponding data signal to be displayed satisfy the gamma curve.

[0071] Step S24: If not, then determine that the grayscale to be displayed and its corresponding data signal to be displayed do not satisfy the gamma curve.

[0072] When determining whether the grayscale to be displayed and its corresponding data signal satisfy the gamma curve, it is only necessary to determine whether the target coordinates are located on the gamma curve, that is, whether the relationship corresponding to the gamma curve is satisfied. If the relationship is not satisfied, it is determined that the grayscale optimization condition is satisfied, and the screen to be displayed needs to be displayed in multiple sub-frames based on the solution of this application. Otherwise, it is determined that the grayscale optimization condition is not satisfied, and multiple sub-frames are not required. The grayscale to be displayed can be directly controlled by controlling the sub-pixels based on the data signal to be displayed.

[0073] Optionally, during the refresh cycle of the screen to be displayed, the display of the first grayscale by controlling the sub-pixels based on the first data signal includes: determining the first grayscale of the sub-pixels in different sub-frames and the corresponding first data signal based on the number of sub-frames divided by the refresh cycle. The first grayscale and the first data signal corresponding to each sub-frame are related to the number of sub-frames divided by the refresh cycle. Multiple sets of first grayscale and their corresponding first data signals need to be pre-stored for different numbers of sub-frames, so that when the grayscale optimization conditions are met, the first grayscale and the first data signal corresponding to each sub-frame can be read, and the brightness of the grayscale to be displayed can be accurately displayed through equivalent multi-sub-frame display.

[0074] refer to Figure 6 , Figure 6 This is a flowchart illustrating another display driving method provided in an embodiment of this application. Figure 3 Based on the display driver method shown, Figure 6 The display driver method shown also includes:

[0075] Step S10: Pre-store multiple information tables, the information tables including: when the refresh cycle is divided into a preset number of subframes, the first data signals corresponding to multiple different first gray levels; wherein, different information tables correspond to different preset numbers.

[0076] When multiple information tables are pre-stored, different preset numbers of subframes correspond to different information tables. After determining the number of subframes, the first gray level and first data signal to be displayed for each subframe can be obtained by querying the corresponding information table. This allows for accurate equivalent display of the brightness of the gray level to be displayed by displaying the corresponding first gray level in multiple subframes.

[0077] Figure 6 In the illustrated method, an information table is pre-stored for dividing the refresh cycle into multiple preset numbers. The information table includes the first data signals corresponding to multiple different first gray levels for each preset number of times. Thus, when the above display driving method is executed, the first gray level and corresponding first data signal for each sub-frame controlled by the selected refresh cycle can be selected from the corresponding information table based on the number of sub-frames into which the refresh cycle is divided.

[0078] Brightness information detection of the display panel can be performed to obtain the first data signal corresponding to different first gray levels when the display panel displays multiple subframes according to a preset number of subframes. Brightness information detection is required before the display panel leaves the factory to obtain the gamma curve. During the brightness detection process required to obtain the gamma curve, the first data signal corresponding to different first gray levels when the display panel displays multiple subframes according to a preset number of subframes can be simultaneously obtained based on the brightness detection data. This eliminates the need for a separate brightness information detection process.

[0079] When multiple information tables are pre-stored, step S13 above divides the refresh cycle of the screen to be displayed into multiple subframes, including: determining the number of subframes to be divided in the refresh cycle based on input information representing the number of subframes. This method can divide the refresh cycle into different numbers of subframes based on input information, making the division of the refresh cycle into multiple subframes more diverse. The preset number corresponding to different information tables can be set according to requirements, such as 2 or 4, etc., and this application embodiment does not limit this. When multiple information tables are pre-stored, the display driving method can be as follows: Figure 7 As shown.

[0080] refer to Figure 7 As shown, Figure 7 This is a flowchart illustrating another display driving method provided in an embodiment of this application. The display driving method includes:

[0081] Step S31: Obtain the grayscale of the sub-pixel in a frame of the image to be displayed.

[0082] Step S32: Determine whether the grayscale to be displayed meets the grayscale optimization conditions of the gamma curve.

[0083] Step S33: If yes, determine the number of subframes to be divided in the refresh period based on the input information representing the number of subframes.

[0084] Step S34: Based on the number of subframes divided by the refresh cycle, select the corresponding information table. In the selected information table, determine the first grayscale and the corresponding first data signal to be displayed for each subframe.

[0085] Figure 7 In the display driving method shown, steps S31-S32 are the same as steps S11-S12 in the above embodiment. The difference from the above embodiment includes: when the grayscale optimization condition of the gamma curve is met, the method of dividing the refresh cycle of the screen to be displayed into multiple sub-frames is as shown in step S33. Thus, as described above, the refresh cycle can be divided into different numbers of sub-frames based on the input information, making the division of the refresh cycle into multiple sub-frames more diverse.

[0086] Figure 7 The method shown differs from the aforementioned implementation in that it further includes: during the refresh cycle of the screen to be displayed, a method for controlling the display of a first grayscale level by controlling the sub-pixels based on the first data signal, as shown in step S34. In this way, by using the number of sub-frames currently divided in the refresh cycle as the target preset number, the corresponding information table can be determined. From this information table, the first grayscale level to be displayed for each sub-frame and the corresponding first data signal can be selected.

[0087] In other embodiments, the display driving method may also pre-store an information table, which corresponds to the first data signals of multiple first gray levels when the refresh cycle is divided into a first number of subframes.

[0088] When only one information table is stored in advance, and the grayscale optimization conditions of the gamma curve are met, the refresh cycle is directly divided into a first number of subframes based on a fixed subframe division method. This subframe division method is simple and unique. When the grayscale optimization conditions of the gamma curve are met, the division of the refresh cycle into a fixed number of subframes can be automatically achieved without manual user intervention. At this time, brightness information can also be detected on the display panel to obtain the first data signal corresponding to different first grayscale levels when the display panel displays multiple subframes according to the first number of subframes.

[0089] When an information table is pre-stored, the display driving method divides the refresh cycle of the screen to be displayed into multiple subframes, including dividing the refresh cycle into a first number of subframes. At this time, as mentioned above, when the grayscale optimization condition of the gamma curve is met, the division of the refresh cycle into a fixed number of subframes can be automatically achieved. The first number can be set based on requirements, such as 2 or 4, etc., and this application embodiment does not limit this. When an information table is pre-stored, the display driving method can be as follows: Figure 8 As shown.

[0090] refer to Figure 8 As shown, Figure 8 This is a flowchart illustrating another display driving method provided in an embodiment of this application. Figure 3 Based on the display driver method shown, Figure 8 The display driver method shown also includes:

[0091] Step S41: Obtain the grayscale of the sub-pixel in a frame of the image to be displayed.

[0092] Step S42: Determine whether the grayscale to be displayed meets the grayscale optimization conditions of the gamma curve.

[0093] Step S43: If so, divide the refresh cycle into a first number of subframes.

[0094] Step S44: Read the data stored in the information table and determine the first grayscale and the corresponding first data signal to be displayed in each subframe.

[0095] Figure 8 In the display driving method shown, steps S41-S42 are the same as steps S11-S12 in the above embodiment. The difference from the above embodiment includes: when the grayscale optimization condition of the gamma curve is met, a method for dividing the refresh cycle of the screen to be displayed into multiple sub-frames is shown in step S43. Thus, as described above, the division of the refresh cycle into a fixed number of sub-frames can be automatically achieved.

[0096] Figure 8 The method shown differs from the aforementioned implementation in that it further includes: during the refresh cycle of the screen to be displayed, a method for controlling the display of a first grayscale level by controlling the sub-pixels based on the first data signal, as shown in step S44. In this way, the refresh cycle can be automatically divided into a fixed number of sub-frames, and then the first grayscale level to be displayed and the corresponding first data signal for each sub-frame can be directly selected from the information table.

[0097] In the above embodiments, the method of dividing the refresh period of the screen to be displayed into multiple subframes can be as follows: Figure 9As shown in step S53, the refresh cycle is divided into multiple sub-frames of the same duration; wherein, in the multiple sub-frames, the duration of the light emission phase of the sub-pixel is not exactly the same, thereby enabling a PWM driving method for grayscale display based on the duration of the light emission phase.

[0098] refer to Figure 9 As shown, Figure 9 This is a flowchart illustrating another display driving method provided in an embodiment of this application. Based on the display driving method of the above embodiments, Figure 9 The display driving method shown includes:

[0099] Step S51: Obtain the grayscale of the sub-pixel in a frame of the image to be displayed.

[0100] Step S52: Determine whether the grayscale to be displayed meets the grayscale optimization conditions of the gamma curve.

[0101] Step S53: If so, divide the refresh cycle into multiple subframes of the same duration; wherein, the duration of the emission phase of the subpixel is not exactly the same in the multiple subframes.

[0102] Step S54: During the refresh cycle of the screen to be displayed, the sub-pixels are controlled to display a first gray level based on the first data signal, wherein at least some sub-frames have a first gray level greater than the gray level to be displayed, at least some sub-frames have a first gray level less than the gray level to be displayed, and the first gray level is not equal to the gray level to be displayed; wherein the first gray level and the corresponding first data signal satisfy the gamma curve.

[0103] Figure 9 In the display driving method shown, the process of steps S51-S52 is the same as that of steps S11-S12 in the above embodiment. The difference from the above embodiment is that the method of dividing the refresh period of the screen to be displayed into multiple sub-frames is as shown in step S53.

[0104] exist Figure 9 In the display driving method shown, regardless of whether the refresh cycle is divided into a fixed first number of subframes or into a preset number of subframes related to the input information, the duration of each subframe in the refresh cycle is the same. This allows for the direct division of the refresh cycle into multiple subframes of equal duration, facilitating the division of the refresh cycle into multiple subframes.

[0105] Optionally, within the multiple subframes divided in the same refresh cycle, each subframe has the same duration, but the duration of the light-emitting phase during the light-emitting process differs between different subframes, in order to facilitate PWM driving. Having the same duration for different subframes but different durations for the data writing phase allows for different durations of the light-emitting phase during the light-emitting process in different subframes.

[0106] The method described above for dividing the refresh period into multiple subframes of equal duration can be as follows: Figure 10 As shown.

[0107] refer to Figure 10 As shown, Figure 10 A flowchart of a multi-subframe partitioning method with a refresh period provided in this application embodiment is included. The method includes:

[0108] Step S61: Obtain the refresh rate of the screen to be displayed.

[0109] Step S62: Determine whether the refresh rate of the screen to be displayed is greater than the set frequency.

[0110] Step S63: If so, reduce the refresh rate, extend the refresh period from the first period time to the second period time, and divide the second period time into multiple subframes.

[0111] Step S64: If not, divide the first cycle time into multiple subframes based on the first cycle time of the refresh cycle.

[0112] Optional, in Figure 10 In the method shown, the set frequency is not less than 120Hz.

[0113] Based on the above embodiments, another embodiment of this application also provides a display driver chip, which can execute the above display driving method.

[0114] refer to Figure 11 As shown, Figure 11 This is a schematic diagram of a display driver chip provided in an embodiment of this application. The display driver chip includes:

[0115] Acquisition module 11 is used to acquire the grayscale of a sub-pixel in a frame of the image to be displayed;

[0116] Processing module 12 is used to determine whether the grayscale to be displayed meets the grayscale optimization conditions of the gamma curve; if so, the refresh cycle of the screen to be displayed is divided into multiple subframes.

[0117] The driving module 13 is used to control the sub-pixels to display a first gray level based on the first data signal during the refresh cycle of the screen to be displayed. The first gray level corresponding to at least some sub-frames is greater than the gray level to be displayed, the first gray level corresponding to at least some sub-frames is less than the gray level to be displayed, and the first gray level is not equal to the gray level to be displayed. The first gray level and the corresponding first data signal satisfy the gamma curve.

[0118] If the grayscale to be displayed satisfies the grayscale optimization conditions of the gamma curve, it indicates that the sub-pixels cannot accurately display the brightness of the grayscale to be displayed based on the data signal to be displayed. The display driver chip can split the grayscale to be displayed that cannot accurately display its brightness into two or more first grayscale combinations, divide one refresh cycle into multiple subframes, and control the sub-pixels to display the first grayscale based on the first data signal in each subframe, so as to effectively display the grayscale to be displayed and accurately display its brightness.

[0119] refer to Figure 12 As shown, Figure 12 This is a schematic diagram of another display driver chip provided in an embodiment of this application. Based on the above embodiment, Figure 12 The display driver chip shown includes a processing module 12, comprising: a first judgment unit 121, used to judge whether the grayscale to be displayed and its corresponding data signal to be displayed satisfy the gamma curve; and a first determination unit 122, used to determine that the grayscale optimization condition is satisfied when the grayscale to be displayed and its corresponding data signal to be displayed do not satisfy the gamma curve; and to determine that the grayscale optimization condition is not satisfied when the grayscale to be displayed and its corresponding data signal to be displayed satisfy the gamma curve.

[0120] When the first judgment unit 121 judges whether the gray level to be displayed and its corresponding data signal to be displayed satisfy the gamma curve, it only needs to judge whether the target coordinates are located on the gamma curve, that is, whether the relationship corresponding to the gamma curve is satisfied. If the relationship is not satisfied, it is determined that the gray level optimization condition is satisfied, and the screen to be displayed needs to be displayed in multiple sub-frames based on the solution of this application. Otherwise, it is determined that the gray level optimization condition is not satisfied, and multiple sub-frames are not required. The gray level to be displayed can be directly controlled by controlling the sub-pixels based on the data signal to be displayed.

[0121] refer to Figure 13 As shown, Figure 13 This is a schematic diagram of another display driver chip provided in an embodiment of this application. The driver module 13 shown includes a second determining unit 131, which is used to determine the first gray level and corresponding first data signal of a sub-pixel in different sub-frames based on the number of sub-frames divided by the refresh cycle. The first gray level and first data signal corresponding to each sub-frame are related to the number of sub-frames divided by the refresh cycle. Multiple sets of first gray levels and their corresponding first data signals need to be pre-stored when the number of sub-frames is different, so that when the gray level optimization conditions are met, the first gray level and first data signal corresponding to each sub-frame can be read, and the brightness of the gray level to be displayed can be accurately displayed through multiple sub-frames.

[0122] refer to Figure 14 As shown, Figure 14This is a schematic diagram of another display driver chip provided in an embodiment of this application. Figures 11-13 Based on the display driver chip provided in any embodiment, Figure 14 The display driver chip shown also includes a first storage module 14, which is used to pre-store multiple information tables. Each information table includes first data signals corresponding to multiple different first gray levels when the refresh cycle is divided into a preset number of subframes. Different information tables correspond to different preset numbers. When multiple information tables are pre-stored, different preset number subframe division methods correspond to different information tables. After determining the number of subframes, the first gray level and first data signal to be displayed for each subframe can be obtained by querying the corresponding information table, so as to accurately and equivalently display the brightness of the gray level to be displayed by displaying the corresponding first gray level separately through multiple subframes.

[0123] refer to Figure 15 As shown, Figure 15 This is a schematic diagram of another display driver chip provided in an embodiment of this application. Figure 14 Based on the display driver chip shown, Figure 15 In the display driver chip shown, the processing module 12 includes a third determining unit 123, which is used to determine the number of subframes to be divided in the refresh cycle based on input information representing the number of subframes. When multiple information tables are pre-stored, different preset numbers of subframes correspond to different information tables. After determining the number of subframes, the first grayscale and first data signal to be displayed for each subframe can be obtained by querying the corresponding information table, so as to accurately and equivalently display the brightness of the grayscale to be displayed by displaying the corresponding first grayscale in multiple subframes respectively.

[0124] refer to Figure 16 As shown, Figure 16 This is a schematic diagram of another display driver chip provided in an embodiment of this application. Figures 11-13 Based on the display driver chip provided in any embodiment, Figure 16 The display driver chip also includes: a second storage module, which pre-stores an information table corresponding to the first data signals of multiple first gray levels when the refresh cycle is divided into a first number of subframes; and a processing module including a first division unit 124, which divides the refresh cycle into a first number of subframes. In this way, the refresh cycle can be automatically divided into a fixed first number of subframes, and then the first gray level and corresponding first data signal to be displayed in each subframe can be directly selected from the information table.

[0125] In the display driver chip provided in this application embodiment, the processing module 12 is used to divide the refresh cycle into multiple subframes of equal duration. Among these subframes, the duration of the light-emitting phase of each subpixel is not entirely the same, thereby enabling a PWM driving method for grayscale display based on the duration of the light-emitting phase. Whether the refresh cycle is divided into a fixed first number of subframes or a preset number of subframes related to the input information, the duration of each subframe is the same. This allows for the direct division of the refresh cycle into multiple subframes of equal duration, facilitating the division of the refresh cycle into multiple subframes.

[0126] refer to Figure 17 As shown, Figure 17 This is a schematic diagram of a processing module provided in an embodiment of this application. In this embodiment, the processing module 12 includes:

[0127] The second judgment unit 21 is used to determine whether the refresh rate of the screen to be displayed is greater than the set frequency.

[0128] The second division unit 22 is used to reduce the refresh frequency when the refresh frequency is greater than the set frequency, extend the refresh period from the first period time to the second period time, and divide the second period time into multiple subframes.

[0129] The third division unit 23 is used to divide the second cycle time into multiple subframes based on the first cycle time of the refresh period when the refresh frequency is not greater than a set frequency. The set frequency is not less than 120Hz.

[0130] If the refresh rate of the image to be displayed is too high, exceeding the set frequency, the refresh cycle will be too short. When the refresh cycle is divided into multiple subframes, some subframes will not have enough charging time, thus failing to accurately display the corresponding first grayscale. This application's embodiment solves the above problem by extending the refresh cycle from the first cycle time to the second cycle time and dividing the second cycle time into multiple subframes.

[0131] If the refresh rate of the screen to be displayed is not greater than the set frequency, then when the screen refresh cycle is divided into multiple subframes for display, the charging time of the multiple subframes divided based on the first cycle time can meet the requirements, and thus the corresponding first gray level can be accurately displayed during the light emission stage.

[0132] refer to Figure 18 As shown, Figure 18This is a schematic diagram illustrating the principle of a display driver chip controlling a display panel, provided in an embodiment of this application. When the grayscale optimization conditions of the gamma curve are met, the display driver chip can read the sub-frame image data from an information table based on the number of sub-frames divided by the refresh cycle and the original image data. It then controls the sub-pixels to sequentially display the corresponding first grayscale level in each sub-frame based on the first data signal in the sub-frame image data. The initial image data includes the grayscale level to be displayed and the data signal to be displayed for the sub-pixels in the image to be displayed. The information table can be programmed into the display driver chip using an OTP (One-Time Programmable) method.

[0133] After the original image data is input, the first data signal of each sub-pixel in the image corresponding to the original data at different first gray levels is determined according to the information table and buffered. Based on the number of subframes and the refresh rate, a timing sequence that conforms to the subframe output frequency is formed, and the buffered data is called to output the subframe image data according to the determined timing sequence.

[0134] based on Figure 18 As shown, the technical solution of this application can split the original screen data into multiple sub-screen data when driving the display panel to display images, and display them sequentially in the form of sub-frames. The algorithm ensures the immediacy and accuracy of input and output operations and guarantees data stream synchronization.

[0135] The technical solution of this application can display grayscale that cannot accurately display brightness by combining multiple first grayscale that can accurately display brightness into multiple subframes. It can accurately present the brightness of all grayscale levels according to the brightness relationship of the gamma curve, and in particular, it can ensure the accurate differentiation and display of low grayscale brightness.

[0136] A refresh cycle is divided into multiple subframes, and the corresponding first grayscale level is displayed sequentially in each subframe based on the first data signal. In any two temporally adjacent subframes, one displays a first grayscale level higher than the grayscale to be displayed, and the other displays a first grayscale level lower than the grayscale to be displayed. This allows for rapid switching between the first grayscale levels adjacent to the grayscale to be displayed while sequentially displaying the first grayscale levels of each subframe, ensuring that the luminous flux per unit time accurately represents the brightness of the grayscale to be displayed.

[0137] In multiple subframes divided within the same refresh cycle, the first grayscale level displayed may not be exactly the same, and the first grayscale level displayed by multiple subframes can exhibit periodic changes. It is possible to configure the first grayscale level displayed in odd-numbered subframes to be the same, and the first grayscale level displayed in even-numbered subframes to be the same, but also different from that displayed in even-numbered subframes. In other methods, the first grayscale level displayed by multiple subframes may not change periodically; in this case, the first grayscale levels displayed in each odd-numbered subframe may not be exactly the same, and the first grayscale levels displayed in each even-numbered subframe may not be exactly the same.

[0138] For example, a refresh cycle can be divided into 2N subframes, which are sequentially designated as subframe 1 to subframe 2N based on the display timing, where N is a positive integer. Gray level 15 is the gray level to be displayed that cannot accurately represent brightness, while gray levels 14 and 16 are the two first gray levels that can accurately represent brightness. It can be set that the first gray level displayed in odd-numbered subframes is gray level 14, and the first gray level displayed in even-numbered subframes is gray level 15.

[0139] In this embodiment, one of the first gray levels displayed in any two adjacent subframes is greater than the gray level to be displayed, and the other is less than the gray level to be displayed. This allows the first gray level greater than the gray level to be displayed and the first gray level less than the gray level to be displayed to be displayed quickly and alternately during the sequential display of each subframe, so that the luminous flux per unit time can accurately represent the brightness of the gray level to be displayed.

[0140] Table 1

[0141] Grayscale to be displayed The first grayscale displayed in the first subframe F1 The first grayscale displayed in the second subframe F2 16 15 17 14 13 15 12 11 13

[0142] Table 1 above shows the equivalent display of the first gray level displayed in the first subframe F1 and the second subframe F2 for three different gray levels to be displayed based on the first gray level displayed in the first subframe F1 and the second subframe F2.

[0143] As shown in Table 1 above, the refresh cycle of a frame to be displayed is divided into two subframes. According to the scanning time, these two subframes are the first subframe F1 and the second subframe F2, respectively. The first gray level displayed in the first subframe F1 is smaller than the gray level to be displayed, and the first gray level displayed in the second subframe F2 is larger than the gray level to be displayed.

[0144] refer to Figure 19 As shown, Figure 19 This application provides an image timing diagram as an embodiment. Figure 19 The upper middle figure shows the timing of the original image when the grayscale to be displayed is based on the data to be displayed. This method divides a frame of original image F0 into the first subframe F1 and the second subframe F2.

[0145] Table 2

[0146]

[0147] Table 2 above shows the equivalent display of the first gray level displayed in the first to fourth subframes F1 to F4 for 12 different gray levels to be displayed when a refresh cycle is divided into the first subframe F1 to the fourth subframe F4. When the gray level to be displayed is 1, if the minimum first gray level is 8, then the number of subframes in a refresh cycle needs to be set to at least 8 so that all subframes have an equivalent display effect of 1 gray level.

[0148] As shown in Table 2 above, the refresh cycle of a frame to be displayed is divided into 4 subframes. According to the scanning time, these 4 subframes are, in order, the first subframe F1 to the fourth subframe F4. The first gray level displayed in the first subframe F1 is smaller than the gray level to be displayed, and the first gray level displayed in the second subframe F2 is larger than the gray level to be displayed.

[0149] refer to Figure 20 As shown, Figure 20 This is another image timing diagram provided in the embodiments of this application. Figure 20 The upper middle figure shows the original image timing based on the data to be displayed and the grayscale to be displayed. This method divides a frame of original image F0 into the first subframe F1 to the second subframe F4.

[0150] When displaying a single frame of an image using multiple subframes, the difference between the average value of the first grayscale displayed by all subframes and the grayscale to be displayed is set to be no more than 1. In other words, the number of subframes divided by the refresh cycle in a single frame of an image to be displayed is set to n, where n is a positive integer greater than 1. The sum of the first grayscale displayed by the n subframes is A, and the grayscale to be displayed is G0. The difference between A / n and G0 is no greater than 1, so that sub-pixels can accurately display the brightness of each grayscale to be displayed and distinguish the brightness of adjacent grayscales.

[0151] In this embodiment, n can be selected based on different effects, and the value of n is not specifically limited. As mentioned above, multiple information tables corresponding to different n can be pre-stored. When n is different, the output timing of each subframe needs to be adapted to the value of n.

[0152] refer to Figure 21 , Figure 21 This is another image timing diagram provided in the embodiments of this application, which is similar to... Figure 19 The difference is that each frame of the original image F0 extends the refresh period from the first period time to the second period time, and then divides the second period time into the first subframe F1 and the second subframe F2.

[0153] refer to Figure 22 , Figure 22 This is another image timing diagram provided in the embodiments of this application, which is similar to... Figure 20 The difference is that the refresh period of each original image F0 is extended from the first period time to the second period time, and then the second period time is divided equally into the first subframe F1 to the fourth subframe F4.

[0154] When the original image is a static input frame, the original image data content of each frame is the same. In this case, it is preferable to extend the refresh cycle from the first cycle time to the second cycle time, and then divide the second cycle time into multiple subframes.

[0155] The display driver chip provided in this application can execute the above-described display driving method, control the display panel for display based on PWM driving mode, decompose the original image data into multiple sub-frame image data according to a pre-stored information table, and display each sub-frame image sequentially in a predetermined timing sequence through data transfer processing. The number of sub-frames can be set to two or more, with different numbers of sub-frames corresponding to different information tables, and the display control is performed sequentially according to the adapted timing sequence. The display timing sequence of each sub-frame can be a dynamic image synchronized with the input timing sequence, or a static image with a certain delay or timing matching relationship.

[0156] Based on the above embodiments, another embodiment of this application also provides a display device, which is as follows: Figure 23 As shown, Figure 23 This is a schematic diagram of the structure of a display device provided in an embodiment of this application. The display device includes a display driver chip 100, which can be any of the display driver chips described in the above embodiments.

[0157] The display device can be an electronic device such as a mobile phone, tablet, or wearable device. The display device can display grayscale levels that cannot be accurately displayed otherwise through multiple subframes, thus improving display quality.

[0158] The various embodiments in this specification are described in a progressive, parallel, or combined manner. Each embodiment focuses on the differences from other embodiments, and the same or similar parts between the embodiments can be referred to each other.

[0159] It should be noted that, in the description of this application, the accompanying drawings and embodiments are illustrative rather than restrictive. The same reference numerals throughout the embodiments identify the same structures. Additionally, for ease of understanding and description, the thicknesses of some layers, films, panels, regions, etc., may be exaggerated in the drawings. It is also understood that when an element such as a layer, film, region, or substrate is referred to as being "on" another element, the element may be directly on the other element or there may be intermediate elements. Furthermore, "on" means positioning an element on or below another element, but does not inherently mean positioning it above another element according to the direction of gravity.

[0160] The terms "upper," "lower," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application. When a component is considered to be "connected" to another component, it can be directly connected to the other component or there may be a component positioned centrally in the middle.

[0161] It should also be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that an article or apparatus comprising a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such an article or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the article or apparatus that includes the aforementioned element.

[0162] The above description of the disclosed embodiments enables those skilled in the art to make or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A display driving method of a display panel, characterized by, The method comprises the following steps: acquiring a to-be-displayed gray scale of a sub-pixel in a frame of to-be-displayed image; determining whether the to-be-displayed gray scale meets a gray scale optimization condition of a gamma curve; if yes, dividing a refresh period of the to-be-displayed image into a plurality of sub-frames; controlling the sub-pixel to display a first gray scale based on a first data signal in the refresh period of the to-be-displayed image, wherein the first gray scale corresponding to at least part of the sub-frames is greater than the to-be-displayed gray scale, the first gray scale corresponding to at least part of the sub-frames is less than the to-be-displayed gray scale, and the first gray scale is not equal to the to-be-displayed gray scale; the first gray scale and the corresponding first data signal meet the gamma curve; the method for determining whether the gray scale optimization condition is met comprises: if the to-be-displayed gray scale and the corresponding to-be-displayed data signal do not meet the gamma curve, it is determined that the gray scale optimization condition is met; if the to-be-displayed gray scale and the corresponding to-be-displayed data signal meet the gamma curve, it is determined that the gray scale optimization condition is not met.

2. The display driving method according to claim 1, wherein controlling the sub-pixel to display a first gray scale based on a first data signal in the refresh period of the to-be-displayed image comprises: determining the first gray scale of the sub-pixel in different sub-frames and the corresponding first data signal based on the number of sub-frames divided by the refresh period.

3. The display driving method according to claim 2, wherein The method further comprises: pre-storing a plurality of information tables, wherein the information tables comprise: a plurality of first data signals corresponding to a plurality of different first gray scales when the refresh period is divided into a preset number of sub-frames; wherein different information tables correspond to different preset numbers.

4. The display driving method according to claim 3, wherein dividing the refresh period of the to-be-displayed image into a plurality of sub-frames comprises: determining the number of sub-frames divided by the refresh period based on input information representing the number of sub-frames.

5. The display driving method according to claim 2, wherein an information table is pre-stored, and the information table corresponds to a plurality of first data signals corresponding to a plurality of first gray scales when the refresh period is divided into a first number of sub-frames; dividing the refresh period of the to-be-displayed image into a plurality of sub-frames comprises: dividing the refresh period into a first number of sub-frames.

6. The display driving method according to claim 1, wherein dividing the refresh period of the to-be-displayed image into a plurality of sub-frames comprises: dividing the refresh period into a plurality of sub-frames with the same time length; wherein in the plurality of sub-frames, the light-emitting phase duration of the sub-pixel is not completely the same.

7. The display driving method according to claim 6, wherein dividing the refresh period into a plurality of sub-frames with the same time length comprises: determining whether the refresh frequency of the to-be-displayed image is greater than a set frequency; if yes, reducing the refresh frequency, extending the refresh period from a first cycle time to a second cycle time, and dividing the second cycle time into a plurality of sub-frames; if no, dividing the first cycle time of the refresh period into a plurality of sub-frames based on the first cycle time.

8. The display driving method according to claim 7, wherein The set frequency is not less than 120 Hz.

9. A display driving chip, characterized in that, The method comprises the following steps: an acquisition module is configured to acquire a to-be-displayed gray scale of a sub-pixel in a frame of to-be-displayed image; a processing module is configured to determine whether the to-be-displayed gray scale meets a gray scale optimization condition of a gamma curve; if yes, divide a refresh period of the to-be-displayed image into a plurality of sub-frames; The driving module is configured to control the sub-pixels to display a first gray scale based on a first data signal in a refresh cycle of the picture to be displayed, wherein the first gray scale corresponding to at least part of the sub-frames is greater than the gray scale to be displayed, the first gray scale corresponding to at least part of the sub-frames is less than the gray scale to be displayed, and the first gray scale is not equal to the gray scale to be displayed. The first gray scale and the corresponding first data signal satisfy the gamma curve. The processing module comprises: A first judging unit configured to judge whether the gray scale to be displayed and the corresponding data signal to be displayed satisfy the gamma curve. A first determining unit configured to determine that the gray scale optimization condition is satisfied when the gray scale to be displayed and the corresponding data signal to be displayed do not satisfy the gamma curve, and determine that the gray scale optimization condition is not satisfied when the gray scale to be displayed and the corresponding data signal to be displayed satisfy the gamma curve.

10. The display driver chip of claim 9, wherein, The driving module comprises: A second determining unit configured to determine the first gray scale and the corresponding first data signal of the sub-pixels in different sub-frames based on the number of sub-frames divided in the refresh cycle.

11. The display driver chip of claim 10, wherein, The display driving chip further comprises a first storage module configured to pre-store a plurality of information tables, wherein the information tables comprise first data signals corresponding to a plurality of different first gray scales when the refresh cycle is divided into a preset number of sub-frames. Different information tables correspond to different preset numbers.

12. The display driver chip of claim 11, wherein, The processing module comprises a third determining unit configured to determine the number of sub-frames divided in the refresh cycle based on input information representing the number of sub-frames.

13. The display driver chip of claim 10, wherein, The display driving chip further comprises a second storage module configured to pre-store an information table corresponding to first data signals corresponding to a plurality of first gray scales when the refresh cycle is divided into a first number of sub-frames. The processing module comprises a first dividing unit configured to divide the refresh cycle into a first number of sub-frames.

14. The display driver chip of claim 9, wherein, The processing module is configured to divide the refresh cycle into a plurality of sub-frames with the same time length. In the plurality of sub-frames, the duration of the light-emitting phase of the sub-pixels is not completely the same.

15. The display driver chip of claim 14, wherein, The processing module comprises: A second judging unit configured to judge whether the refresh frequency of the picture to be displayed is greater than a set frequency. A second dividing unit configured to, when the refresh frequency is greater than the set frequency, reduce the refresh frequency, extend the refresh cycle from a first cycle time to a second cycle time, and divide the second cycle time into a plurality of sub-frames. A third dividing unit configured to, when the refresh frequency is not greater than the set frequency, divide a first cycle time of the refresh cycle into a plurality of sub-frames based on the first cycle time.

16. A display device comprising: The display driving chip comprises any one of claims 9-15.

Images