Brightness compensation method of display device, chip and display device

Abstract

The present disclosure relates to the technical field of display, and discloses a display device brightness compensation method, a chip and a display device. The brightness compensation method comprises the following steps: obtaining a gamma preset value; obtaining a display brightness value to be compensated, a light-emitting control signal input and output difference offset value; generating a pulse width of a low-level input signal of a light-emitting start signal before processing by a brightness control table; obtaining a minimum change pulse width of the low-level input signal of the light-emitting start signal after processing, and calculating a gamma index value by a gamma index value calculation module; searching for a gamma compensation value corresponding to the gamma index value by a gamma index value and gamma compensation value relationship lookup table; and outputting the gamma preset value and the gamma compensation value as an actual gamma value after brightness compensation. The chip is used to execute the above brightness compensation method. The display device adopts the above brightness compensation method for brightness compensation. The present disclosure can improve display brightness jump, which is beneficial to improve display quality and ensure user experience.

Description

Technical Field

[0001] This disclosure relates to the field of display technology, and in particular to a brightness compensation method, chip, and display device for a display device. Background Technology

[0002] In display technology, Organic Light Emitting Diode (OLED) displays are widely recognized as the third-generation display technology after Liquid Crystal Display (LCD) due to their numerous advantages, including thinness, active light emission, fast response speed, wide viewing angle, rich colors, high brightness, low power consumption, and resistance to high and low temperatures. Among them, Active Matrix Organic Light Emitting Diode (AMOLED) can achieve large-size, high-resolution panel designs and has become a current research hotspot.

[0003] However, due to limitations in the driving circuit, existing display panels often experience abrupt changes in display brightness when driving the display, which are perceived by the user's eyes and thus seriously affect the display effect and the user's experience.

[0004] Therefore, providing a brightness compensation method, chip, or display device that can effectively compensate for the brightness of a display panel, improve brightness fluctuations, enhance display quality, and ensure user experience is a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0005] To address the aforementioned technical problems, this disclosure provides a brightness compensation method, a chip, and a display device.

[0006] This disclosure provides a brightness compensation method for a display device, including:

[0007] Get the gamma preset value;

[0008] Obtain the display brightness value to be compensated and the offset value of the difference between the input and output of the illumination control signal;

[0009] Based on the difference offset value between the input and output of the light emission control signal and the display brightness value to be compensated, the pulse width of the low-level input signal in the light emission start signal before processing is generated through the brightness control table;

[0010] The minimum change pulse width of the low-level input signal in the light emission start signal after processing is obtained, and the gamma index value is calculated by the gamma index value calculation module based on the pulse width of the low-level input signal in the light emission start signal before processing.

[0011] The gamma compensation value corresponding to the gamma index value can be found by using a preset lookup table of gamma index value and gamma compensation value.

[0012] The preset gamma value and the gamma compensation value are output together as the actual gamma value corresponding to the brightness value of the display to be compensated.

[0013] Based on the same inventive concept, this disclosure also provides a chip for performing the above-described brightness compensation method.

[0014] Based on the same inventive concept, this disclosure also provides a display device that uses the above-described brightness compensation method for brightness compensation.

[0015] The technical solution provided in this disclosure has the following advantages compared with the prior art:

[0016] The brightness compensation method for the display device disclosed herein can improve the accuracy of brightness adjustment and avoid step-like jumps in display brightness when the display device uses a light emission control signal for dimming. Specifically, the brightness compensation method for the display device disclosed herein involves first obtaining a gamma preset value, which can be understood as the original gamma value preset before brightness compensation. Then, the brightness value to be compensated and the input and output difference offset values ​​of the light emission control signal are obtained. The pulse width of the low-level input signal in the light emission start signal before processing is generated using a brightness control table. Next, the minimum change pulse width of the low-level input signal in the light emission start signal after processing is obtained. This minimum change pulse width is preset and represents the minimum change pulse width of the initial low-level input signal of the light emission signal control circuit in the gate drive circuit after processing. Based on the minimum change pulse width of the low-level input signal in the light emission start signal after processing, the gamma index value is calculated using the gamma index value calculation module according to the pulse width of the low-level input signal in the light emission start signal before processing corresponding to the brightness value to be compensated obtained in the previous step. Then, the gamma compensation value corresponding to the gamma index value is found using a preset gamma index value and gamma compensation value lookup table, thus obtaining the gamma compensation value corresponding to the brightness value to be compensated. Finally, the gamma compensation value is superimposed on the preset gamma value and output as the actual gamma value corresponding to the brightness value to be compensated, which is input into the gamma register to drive the display panel of the display device to emit light. Because the brightness compensation method of the display device provided in this disclosure generates gamma compensation for the display brightness value to be compensated, that is, during the dimming process, at the display brightness value where the original display brightness value changes but the duty cycle of the light emission control signal remains unchanged and the display brightness remains almost unchanged, the display brightness also changes slightly at the corresponding display brightness value to be compensated. In this way, there is a smooth brightness change process throughout the dimming process, avoiding abrupt changes in display brightness, effectively achieving brightness compensation for the display panel, improving display brightness jumps, which is conducive to improving display quality and ensuring user experience. Attached Figure Description

[0017] The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments consistent with this disclosure and, together with the description, serve to explain the principles of this disclosure.

[0018] To more clearly illustrate the technical solutions in the embodiments of this disclosure or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1This is a schematic diagram illustrating how the display brightness and the duty cycle of the light emission control signal of a display device change with the display brightness value in the prior art.

[0020] Figure 2 This is a schematic flowchart of a brightness compensation method for a display device provided in an embodiment of the present disclosure;

[0021] Figure 3 yes Figure 2 The process sequence diagram;

[0022] Figure 4 Is adopted Figure 2 A schematic diagram illustrating how the display brightness and duty cycle of the light emission control signal of a display device change with the display brightness value after the brightness compensation method is applied.

[0023] Figure 5 It is an application Figure 2 A schematic diagram of a planar structure of a display device with a brightness compensation method;

[0024] Figure 6 This is a schematic diagram illustrating the linear correspondence between the display brightness value node and the low-level pulse width duty cycle of the light emission control signal provided in the embodiments of this disclosure;

[0025] Figure 7 This is another schematic flowchart of the brightness compensation method for a display device provided in the embodiments of this disclosure;

[0026] Figure 8 This is another schematic flowchart of the brightness compensation method for a display device provided in the embodiments of this disclosure;

[0027] Figure 9 yes Figure 5 A circuit block diagram of a driver chip;

[0028] Figure 10 Is adopted Figure 2 A comparison diagram of the position of the gamma compensation value fine-tuning step point and the original brightness point after the brightness compensation method. Detailed Implementation

[0029] To better understand the above-mentioned objectives, features, and advantages of this disclosure, the solutions disclosed herein will be further described below. It should be noted that, unless otherwise specified, the embodiments and features described herein can be combined with each other.

[0030] Numerous specific details are set forth in the following description in order to provide a full understanding of this disclosure, but this disclosure may also be implemented in other ways different from those described herein; obviously, the embodiments in the specification are only some, and not all, of the embodiments of this disclosure.

[0031] In existing technologies, when a display device drives an luminescent display, the duty cycle of the luminescence control signal is less precise than the DBV (Display Brightness Value) due to limitations imposed by the display panel's driving circuit. Assuming a display panel is driven by a single driving circuit driving two rows of luminescent devices, the duty cycle of the luminescence control signal (EM signal, or Emit signal) changes only once every four rows. Taking a 2400-line resolution display panel as an example, the duty cycle of the luminescence control signal changes at most 2400 / 4 = 600 times, while the DBV corresponding to luminescence control signal dimming (EM dimming) changes approximately 1000 times or more. Therefore, the precision of the duty cycle of the luminescence control signal is less than the precision of the DBV value. In a known example from a project, the DBV value of the display panel changes 1184 times, while the duty cycle of the luminescence control signal changes only 546 times.

[0032] Therefore, due to the limited precision of the duty cycle variation of the display panel's light emission control signal, the duty cycle of the display panel's light emission control signal changes in a step-like manner with the DBV value, and the brightness of the display panel also exhibits a step-like variation. For example, as... Figure 1 As shown, Figure 1 This is a schematic diagram illustrating the variation of display brightness and the duty cycle of the light emission control signal in a display device as a function of the display brightness value. Lum represents the display brightness of the display panel, measured in nits; EM duty represents the duty cycle of the light emission control signal of the display panel, measured in percent. Figure 1 It can be seen that the DVB value changed 60 times from 500 to 560, while the EM duty, or the duty cycle of the display panel's light-emitting control signal, changes in a step-like, abrupt manner. While the DVB value changed 60 times from 500 to 560, the EM duty only changed 12 times (because the duty cycle of the display panel's light-emitting control signal only changes once every four rows). This means that during EM dimming, when some DVB values ​​change, the EM duty remains unchanged; only when the DVB value changes to certain specific DVB values ​​will the EM duty change, resulting in abrupt changes in display brightness. In other words, at a certain DVB value, if the duty cycle of the display panel's light-emitting control signal changes abruptly, the display brightness will also change abruptly at that DVB value. This kind of abrupt change in display brightness is easily perceived by the user's eyes, severely affecting the display effect and the user experience.

[0033] Therefore, in the existing technology, when dimming with EM, the EM Duty changes step-like with the DBV value, and the display brightness also changes step-like with the DBV value. This results in low accuracy of the display brightness changing with the DBV value, and in severe cases, users may perceive brightness jumps with the naked eye.

[0034] To address the aforementioned issues, this application proposes a brightness compensation method, chip, and display device, which can effectively compensate for display brightness, improve brightness fluctuations, enhance display quality, and ensure a positive user experience. Specific embodiments of the brightness compensation method, chip, and display device proposed in this application are detailed below.

[0035] Please refer to the reference. Figure 2 and Figure 3 , Figure 2 This is a schematic flowchart of a brightness compensation method for a display device provided in an embodiment of this disclosure. Figure 3 yes Figure 2 The flowchart shows a brightness compensation method for a display device provided in this embodiment, which includes:

[0036] S10: Get the preset gamma level;

[0037] S11: Obtain the display brightness value (DBV) to be compensated. (x) The difference between the input and output offset values ​​of the light emission control signal is EM_Low_Offset;

[0038] S12: Based on the difference offset value EM_Low_Offset between the input and output of the light emission control signal and the display brightness value DBV to be compensated. (x) The pulse width EM_Low_In of the low-level input signal in the light emission start signal is generated by the brightness control table (i.e., BC table) before processing.

[0039] S13: Obtain the minimum change pulse width EM_step after processing the low-level input signal in the light emission start signal, and calculate the gamma index value Gamma Level Index based on the pulse width EM_Low_In before processing the low-level input signal in the light emission start signal through the gamma index value calculation module (i.e. GammaLevel Index Calculate).

[0040] S14: Find the gamma level offset corresponding to the gamma level index by using the preset gamma index value and gamma compensation value relationship lookup table (i.e., GammaLevel Index Tooffset LUT);

[0041] S15: The gamma preset value (Gamma Level) and the gamma compensation value (Gamma Level offset) are output together as the display brightness value (DBV) to be compensated. (x) The corresponding actual gamma value (x) .

[0042] Specifically, the brightness compensation method for the display device provided in this embodiment can improve the brightness adjustment accuracy and avoid step-like jumps in display brightness when the display device uses a light emission control signal for dimming. The brightness compensation method for the display device provided in this embodiment compensates for certain DBV values ​​that change during EM dimming but whose EM duty remains unchanged. For example... Figure 1 In the process of DBV values ​​from 500 to 503, since EMduty remains unchanged, the display brightness Lum also remains unchanged. Only when the DBV value becomes 504 does the display brightness undergo a sudden change following the change in EMduty. Therefore, the brightness compensation in this embodiment is for obtaining the actual compensated gamma values ​​corresponding to DBV values ​​of 501-503. Specifically, the brightness compensation method of the display device in this embodiment is as follows: First, obtain the gamma preset value GammaLevel. The gamma preset value GammaLevel can be understood as a preset original gamma value that will not cause a change in display brightness before brightness compensation. Then, obtain the display brightness value DBV to be compensated. (x) The difference offset value between the input and output of the illumination control signal is EM_Low_Offset; where DBV is the display brightness value to be compensated. (x) This can be understood as the DBV value corresponding to the brightness compensation required, such as... Figure 1 Except for DBV values ​​such as 500, 504, 508, and 512, which indicate changes in display brightness, all DBV values ​​that require brightness compensation. The EM_Low_Offset value represents the preset offset between the EM signal input and output in EM dimming mode. Based on the display brightness value DBV to be compensated... (x) The brightness control table (BC table) can generate the pulse width EM_Low_In before processing the low-level input signal in the light emission start signal. Specifically, the brightness control table (BC table) is a table that pre-sets each display brightness value node (DBV node) and each pulse width EM_Low_In node before processing the low-level input signal in the light emission start signal. If the display brightness value DBV to be compensated is found in the brightness control table... (x) Located in DBVnode (1) Values ​​and DBVnode (2)If the values ​​are between 0 and 1, then the display brightness value to be compensated is DBV. (x) The pulse width EM_Low_Innode of the corresponding light emission start signal before processing the low-level input signal (x) Also in DBVnode (1) The value corresponds to EM_Low_Innode (1) and DBVnode (2) The value corresponds to EM_Low_Innode (2) Between; if the display brightness value DBV to be compensated is found in the brightness control table. (x) Located in DBVnode (6) Values ​​and DBV nodes (7) If the values ​​are between 0 and 1, then the display brightness value to be compensated is DBV. (x) The pulse width EM_Low_Innode of the corresponding light emission start signal before processing the low-level input signal (x) Also in DBVnode (6) The value corresponds to EM_Low_Innode (6) and DBVnode (7) The value corresponds to EM_Low_Innode (7) Between; then by looking up the brightness control table, find EM_Low_Innode (1) and EM_Low_Innode (2) By combining the input and output difference offset value of the light emission control signal, EM_Low_Offset, the display brightness value DBV to be compensated can be generated. (x) The pulse width EM_Low_Innode of the corresponding light emission start signal before processing the low-level input signal (x) .

[0043] Next, the minimum change pulse width EM_step after processing the low-level input signal in the light emission start signal is obtained. This minimum change pulse width EM_step is also preset, representing the minimum change pulse width after processing the initial low-level input signal of the light emission signal control circuit in the gate drive circuit. Based on obtaining the minimum change pulse width EM_step after processing the low-level input signal in the light emission start signal, and according to the display brightness value DBV to be compensated obtained in the previous step... (x)The pulse width EM_Low_In of the corresponding light emission start signal before processing the low-level input signal is calculated into the gamma index value Gamma Level Index by the gamma index calculation module (i.e., Gamma Level Index Calculate). This gamma index calculation module, integrated into a driver chip such as an IC, is used to convert and calculate the corresponding gamma signal from the light emission control signal (EM signal). In other words, the gamma index calculation module calculates the display brightness value DBV to be compensated. (x) The corresponding gamma index value is Gamma Level Index. Then, using a preset lookup table (Gamma Level Index To offset LUT) to find the gamma compensation value Gamma Level offset corresponding to the gamma index value Gamma Level Index, we obtain the display brightness value DBV to be compensated. (x) The corresponding gamma compensation value is the Gamma Level offset. The final gamma compensation value (Gamma Level offset) is superimposed on the preset gamma level, and the combined output is the display brightness value (DBV) to be compensated. (x) The corresponding actual gamma value (x) The signal is input into the gamma register, which drives the display panel of the display device to emit light.

[0044] Because the brightness compensation method for the display device provided in this embodiment is for the display brightness value DBV to be compensated... (x) In EM dimming, gamma compensation is applied to DBV values ​​where the original DBV value changes while the EM duty remains constant and the display brightness remains almost unchanged. This results in a change in the corresponding display brightness value to be compensated (DBV). (x) The brightness of the display also changes slightly, resulting in a smooth brightness change process during dimming. This avoids abrupt changes in brightness and effectively compensates for the brightness of the display panel, improving brightness jumps and enhancing display quality to ensure a better user experience.

[0045] like Figure 1 and Figure 4 As shown, Figure 4 Is adopted Figure 2 This diagram illustrates the variation of display brightness and the duty cycle of the light emission control signal of a display device after the brightness compensation method, as a function of the display brightness value. Lum represents the display brightness variation trend of the display device in this embodiment, measured in nits; EM duty represents the duty cycle of the light emission control signal of the display device in this embodiment, measured in percent. (Comparison) Figure 1 and Figure 4It can be seen that the brightness of existing display devices varies in a step-like manner (e.g., Figure 1 (A stepped variation trend) occurs, with brightness abruptly changing only at certain DBV values. However, after applying the brightness compensation method provided in this embodiment, some specific display brightness values ​​(DBV) to be compensated are reduced. (x) Gamma compensation was performed at the location, resulting in a smoother change in display brightness (e.g., Figure 4 The trend of change is shown by the dashed line K in the figure. Figure 4 The dotted line in the middle indicates the display brightness (Lum graphic represents the display brightness change under EM dimming in the prior art), which avoids sudden brightness changes and helps to improve the smoothness of the brightness change of the entire screen, thereby improving display quality.

[0046] In some alternative embodiments, please refer to the references. Figures 2-4 , Figure 5 and Figure 6 , Figure 5 It is an application Figure 2 A schematic diagram of a planar structure of a display device using a brightness compensation method. Figure 6 This is a schematic diagram illustrating the linear correspondence between the display brightness value node and the low-level pulse width duty cycle of the light emission control signal provided in this embodiment of the disclosure. Figure 2 The display device 111 of the brightness compensation method in this embodiment includes a display panel 000. The display panel 000 includes an electrically connected light-emitting control circuit 10 and a light-emitting module 20. The light-emitting control circuit 10 provides a light-emitting control signal EM to the light-emitting module 20. Optionally, the display panel 000 may include a display area AA and a non-display area NA. The light-emitting control circuit 10 may be located in the non-display area NA, i.e., the border area of ​​the display panel 000. The light-emitting module 20 may be a circuit module included in the pixel circuit of the display panel 000. The light-emitting control circuit 10 can provide a light-emitting control signal EM to the light-emitting module 20 through a light-emitting control signal line. It is understood that this embodiment... Figure 5 The diagram below only illustrates the light-emitting control circuit 10 and the light-emitting module 20. In actual implementation, the structure of the display panel 000 includes, but is not limited to, this. For details, please refer to the actual structure of the display panel in related technologies.

[0047] It is understood that the brightness compensation method in this embodiment can be executed by the driver chip attached to the display panel 000. That is, the driver chip can be attached to the lower bezel area of ​​the non-display area NA of the display device 000 or the driver chip can be attached to a flexible circuit board. The module that implements the above-mentioned brightness compensation method is integrated into the driver chip, and brightness compensation can be performed when the display panel 000 is dimmed.

[0048] In the brightness compensation method of the display device 111 provided in this embodiment, the brightness value DBV to be compensated is obtained.(x) Previously, it also included determining the target display brightness value DBV range. The target display brightness value range includes multiple display brightness value nodes (DBV nodes). Different display brightness value nodes (DBV nodes) correspond to different low-level pulse width duty cycles of the luminance control signal (i.e., if the luminance control signal EM is low-level enabled, it means that the pulse width EM_Low_In in the luminance start signal before the low-level input signal is processed). Among them, the display brightness value DBV to be compensated is... (x) It is located between two adjacent DBV nodes that display brightness values.

[0049] This embodiment explains that when the display device 111 dims, the display brightness level is equivalent to a display brightness value node (DBV node). The entire DBV value range is divided into multiple target display brightness value (DBV) intervals corresponding to multiple display brightness levels. There is a PWM dimming interval between two adjacent display brightness levels, and different PWM dimming intervals correspond to different PWM duty cycle ranges. In PWM dimming, the display brightness corresponding to the range of display brightness values ​​is usually adjusted by regulating the low-level pulse width duty cycle (EMduty) of the light emission control signal EM in the pixel circuit and the data voltage provided to the pixel circuit. The low-level pulse width duty cycle (or high-level pulse width duty cycle) of the light emission control signal EM is used to control the duration of light emission of the light-emitting device within one frame, and the magnitude of the data voltage is used to control the driving current flowing through the light-emitting device. The data voltage is generally provided by the driver chip, which drives the display screen to emit light. The data voltage exists in the driver chip in the form of a gamma register value. Therefore, the dimming scheme involved in this embodiment adjusts the display brightness by regulating the low-level pulse width duty cycle of the light emission control signal in the pixel circuit (i.e., if the light emission control signal EM is low-level enabled, it means the pulse width EM_Low_In before the low-level input signal in the light emission start signal is processed) and the gamma register value.

[0050] The entire DBV value range can be divided into multiple target display brightness value DBV intervals corresponding to multiple display brightness levels. Each target display brightness value interval includes multiple display brightness value nodes (DBV nodes), such as... Figure 6 DBVnode shown (1) DBV node (2) ...DBV node (n) DBV node (n+1) ...DBV node (10)The low-level pulse width duty cycle of the luminance control signal corresponding to different display brightness value nodes (DBV nodes) is different (i.e., if the luminance control signal EM is low-level enabled, it means that the pulse width EM_Low_In node in the luminance start signal before the low-level input signal is processed). For example, DBV node (1) The duty cycle of the low-level pulse width of the corresponding light emission control signal, i.e., the pulse width of the low-level input signal in the light emission start signal before processing, is EM_Low_In node. (1) DBV node (2) The duty cycle of the low-level pulse width of the corresponding light emission control signal, i.e., the pulse width of the low-level input signal in the light emission start signal before processing, is EM_Low_In node. (2) ...DBV node (n) The duty cycle of the low-level pulse width of the corresponding light emission control signal, i.e., the pulse width of the low-level input signal in the light emission start signal before processing, is EM_Low_In node. (n) DBV node (n+1) The duty cycle of the low-level pulse width of the corresponding light emission control signal, i.e., the pulse width of the low-level input signal in the light emission start signal before processing, is EM_Low_In node. (n+1) ...DBV node (10) The duty cycle of the low-level pulse width of the corresponding light emission control signal, i.e., the pulse width of the low-level input signal in the light emission start signal before processing, is EM_Low_In node. (10) Among them, the display brightness value (DBV) to be compensated. (x) Located between two adjacent display brightness value nodes DBVnode, such as the display brightness value DBV to be compensated. (x) It can be located in DBV node (1) and DBV node (2) Between, or located in a DBV node (n) and DBV node (n+1) Between, etc.

[0051] Since the brightness control table (BC table) is a table containing preset display brightness value nodes (DBV nodes) and the pulse width EM_Low_Innode of each light emission start signal before processing, if the display brightness value DBV to be compensated is found in the brightness control table... (x) Located in DBVnode (1) Values ​​and DBV nodes (2) If the values ​​are between 0 and 1, then the display brightness value to be compensated is DBV. (x) The pulse width EM_Low_Innode of the corresponding light emission start signal before processing the low-level input signal (x)Also in DBVnode (1) The value corresponds to EM_Low_Innode (1) and DBVnode (2) The value corresponds to EM_Low_Innode (2) Between; then by looking up the brightness control table, find EM_Low_Innode (1) and EM_Low_Innode (2) And by using the preset input and output difference offset value EM_Low_Offset for the light emission control signal, the display brightness value DBV to be compensated can be generated. (x) The pulse width EM_Low_Innode of the corresponding light emission start signal before processing the low-level input signal (x) If the display brightness value DBV to be compensated is found in the brightness control table... (x) Located in DBVnode (n) Values ​​and DBV nodes (n+1) If the values ​​are between 0 and 1, then the display brightness value to be compensated is DBV. (x) The pulse width EM_Low_Innode of the corresponding light emission start signal before processing the low-level input signal (x) Also in DBVnode (n) The value corresponds to EM_Low_Innode (n) and DBVnode (n+1) The value corresponds to EM_Low_Innode (n+1) Between; then by looking up the brightness control table, find EM_Low_Innode (n) and EM_Low_Innode (n+) And by using the preset input and output difference offset value EM_Low_Offset for the light emission control signal, the display brightness value DBV to be compensated can be generated. (x) The pulse width EM_Low_Innode of the corresponding light emission start signal before processing the low-level input signal (x) .

[0052] Optional, such as Figures 2-6 , Figure 7 As shown, Figure 7 This is another schematic flowchart of a brightness compensation method for a display device provided in this embodiment. In this embodiment, the brightness compensation method for the display device includes:

[0053] S20: Get the preset gamma level;

[0054] S21: Obtain the display brightness value (DBV) to be compensated. (x)The difference between the input and output offset values ​​of the light emission control signal is EM_Low_Offset;

[0055] Based on the difference offset value EM_Low_Offset between the input and output of the light emission control signal and the display brightness value DBV to be compensated. (x) The brightness control table (BC table) generates the pulse width EM_Low_In of the low-level input signal in the light emission start signal before processing. In other words, the BC table uses linear interpolation to interpolate and calculate the display brightness value DBV to be compensated. (x) The pulse width EM_Low_Innode of the corresponding light emission start signal before processing the low-level input signal (x) Specifically:

[0056] S221: The target display brightness value range includes the adjacent first display brightness value node DBVnode. (n) Second display brightness value node DBVnode (n+1) The brightness value (DBV) to be compensated (x) Located at the first display brightness value node DBVnode (n) Second display brightness value node DBVnode (n+1) between;

[0057] S222: The brightness control table BC table is based on linear interpolation to obtain the first display brightness value node DBVnode. (n) Corresponding to the first pulse width, the second display brightness value node is DBVnode (n+1) Corresponding to the second pulse width;

[0058] S223: Based on the first pulse width, the second pulse width, and the difference offset value EM_Low_Offset between the input and output of the light emission control signal, calculate using the linear interpolation formula:

[0059] EM_Low_Innode (x) =LinearInterpoltatin(DBV node (n) EM_Low_In

[0060] node (n) DBV node (n+1) EM_Low_In node (n+1) DBV (x) +EM_Low_Offset;

[0061] S224: Calculate the display brightness value (DBV) to be compensated. (x) The corresponding third pulse width;

[0062] Wherein, the first pulse width is the first display brightness value node DBVnode. (n) The pulse width EM_Low_Innode of the corresponding light emission start signal before processing the low-level input signal (n) The second pulse width is the second display brightness value node DBVnode. (n+1) The pulse width EM_Low_Innode of the corresponding light emission start signal before processing the low-level input signal (n+1) The third pulse width is the display brightness value (DBV) to be compensated. (x) The pulse width EM_Low_Innode of the corresponding light emission start signal before processing the low-level input signal (x) .

[0063] S23: Obtain the minimum change pulse width EM_step after processing the low-level input signal in the light emission start signal, and calculate the display brightness value DBV to be compensated. (x) The pulse width EM_Low_Innode of the corresponding light emission start signal before processing the low-level input signal (x) The Gamma Level Index is calculated using the Gamma Index Calculation module.

[0064] S24: Find the gamma level offset corresponding to the gamma level index by using the preset gamma index value and gamma compensation value relationship lookup table (i.e., GammaLevel Index Tooffset LUT);

[0065] S25: The gamma preset value (Gamma Level) and the gamma compensation value (Gamma Level offset) are output together as the display brightness value (DBV) to be compensated. (x) The corresponding actual gamma value (x) .

[0066] This embodiment explains the brightness compensation method, which uses the input and output difference offset value EM_Low_Offset of the light emission control signal and the display brightness value DBV to be compensated. (x) The pulse width EM_Low_Innode of the low-level input signal in the emission start signal generated by the brightness control table BC table is calculated before processing. (x) This includes: the brightness control table BC table, which uses linear interpolation to interpolate and calculate the display brightness value DBV to be compensated. (x) The pulse width EM_Low_Innode of the corresponding light emission start signal before processing the low-level input signal (x) Specifically:

[0067] The target display brightness value range includes the adjacent first display brightness value node DBVnode. (n) Second display brightness value node DBVnode (n+1) The brightness value (DBV) to be compensated (x) Located at the first display brightness value node DBVnode (n) Second display brightness value node DBVnode (n+1) between;

[0068] The brightness control table BC table is based on linear interpolation to obtain the first display brightness value node DBVnode. (n) Corresponding to the first pulse width, the second display brightness value node is DBVnode (n+1) Corresponding to the second pulse width;

[0069] Based on the first pulse width, the second pulse width, and the difference offset value EM_Low_Offset between the input and output of the light emission control signal, the following calculation formula is used:

[0070] EM_Low_Innode (x) =LinearInterpoltatin(DBV node (n) EM_Low_In

[0071] node (n) DBV node (n+1) EM_Low_In node (n+1) DBV (x) +EM_Low_Offset;

[0072] The calculated display brightness value (DBV) is obtained. (x) The corresponding third pulse width;

[0073] Wherein, the first pulse width is the first display brightness value node DBVnode. (n) The pulse width EM_Low_Innode of the corresponding light emission start signal before processing the low-level input signal (n) The second pulse width is the second display brightness value node DBVnode. (n+1) The pulse width EM_Low_Innode of the corresponding light emission start signal before processing the low-level input signal (n+1) The third pulse width is the display brightness value (DBV) to be compensated. (x) The pulse width EM_Low_Innode of the corresponding light emission start signal before processing the low-level input signal (x) .

[0074] In this embodiment, LinearInterpolationTin represents a linear interpolation function. The brightness control table set by this function can only find the pulse width EM_Low_Innode of the low-level input signal in the light emission start signal before processing for each display brightness value node DBVnode. For non-display brightness value nodes, it is necessary to first find the pulse width EM_Low_Innode of the low-level input signal in the light emission start signal before processing for each adjacent display brightness value node DBVnode by looking up the brightness control table BC table. Then, add the offset value, that is, add the offset value EM_Low_Offset of the difference between the light emission control signal input and output, to obtain the display brightness value DBV to be compensated. (x) The pulse width EM_Low_Innode of the corresponding light emission start signal before processing the low-level input signal (x) .

[0075] In some alternative embodiments, please refer to the references. Figures 2-6 , Figure 8 , Figure 8 This is another schematic flowchart of a brightness compensation method for a display device provided in this embodiment. In this embodiment, the brightness compensation method for the display device includes:

[0076] S30: Get the preset gamma level;

[0077] S31: Obtain the display brightness value (DBV) to be compensated. (x) The difference between the input and output offset values ​​of the light emission control signal is EM_Low_Offset;

[0078] Based on the difference offset value EM_Low_Offset between the input and output of the light emission control signal and the display brightness value DBV to be compensated. (x) The brightness control table (BC table) generates the pulse width EM_Low_In of the low-level input signal in the light emission start signal before processing. In other words, the BC table uses linear interpolation to interpolate and calculate the display brightness value DBV to be compensated. (x) The pulse width EM_Low_Innode of the corresponding light emission start signal before processing the low-level input signal (x) Specifically:

[0079] S321: The target display brightness value range includes the adjacent first display brightness value node DBVnode. (n) Second display brightness value node DBVnode (n+1) The brightness value (DBV) to be compensated (x) Located at the first display brightness value node DBVnode (n)Second display brightness value node DBVnode (n+1) between;

[0080] S322: The brightness control table BC table is based on linear interpolation to obtain the first display brightness value node DBVnode. (n) Corresponding to the first pulse width, the second display brightness value node is DBVnode (n+1) Corresponding to the second pulse width;

[0081] S323: Based on the first pulse width, the second pulse width, and the difference offset value EM_Low_Offset between the input and output of the light emission control signal, the following formula is calculated using linear interpolation:

[0082] EM_Low_Innode (x) =LinearInterpoltatin(DBV node (n) EM_Low_In

[0083] node (n) DBV node (n+1) EM_Low_In node (n+1) DBV (x) +EM_Low_Offset;

[0084] S324: Calculate the display brightness value (DBV) to be compensated. (x) The corresponding third pulse width;

[0085] Wherein, the first pulse width is the first display brightness value node DBVnode. (n) The pulse width EM_Low_Innode of the corresponding light emission start signal before processing the low-level input signal (n) The second pulse width is the second display brightness value node DBVnode. (n+1) The pulse width EM_Low_Innode of the corresponding light emission start signal before processing the low-level input signal (n+1) The third pulse width is the display brightness value (DBV) to be compensated. (x) The pulse width EM_Low_Innode of the corresponding light emission start signal before processing the low-level input signal (x) .

[0086] S33: Obtain the minimum change pulse width EM_step after processing the low-level input signal in the light emission start signal, and calculate the display brightness value DBV to be compensated. (x) The pulse width EM_Low_Innode of the corresponding light emission start signal before processing the low-level input signal (x)The Gamma Level Index is calculated using the Gamma Index Calculation module, specifically as follows:

[0087] Gamma Level Index = EM_Low_In % EM_step; where Gamma Level Index represents the gamma index value, and EM_Low_In represents the display brightness value (DBV) to be compensated. (x) The pulse width of the low-level input signal in the corresponding light emission start signal before processing, and EM_step represents the minimum change pulse width of the low-level input signal in the light emission start signal after processing.

[0088] S34: Find the gamma level offset corresponding to the gamma level index by using the preset gamma index value and gamma compensation value relationship lookup table (i.e., GammaLevel Index Tooffset LUT);

[0089] S35: The preset gamma level and the gamma level offset are output together as the display brightness value (DBV) to be compensated. (x) The corresponding actual gamma value (x) .

[0090] This embodiment explains how to obtain the minimum change pulse width EM_step after processing the low-level input signal in the light emission start signal, and how to obtain the pulse width EM_Low_In node(x) of the low-level input signal in the light emission start signal before processing corresponding to the display brightness value DBV(x) to be compensated. Then, the gamma index value Gamma Level Index can be calculated using the gamma index calculation module (i.e., Gamma Level Index Calculate) integrated in the driver chip. Specifically, the gamma index calculation module can calculate the gamma index value as follows: Gamma Level Index = EM_Low_In % EM_step; where EM_Low_In represents the pulse width EM_Low_In node(x) of the low-level input signal in the light emission start signal before processing corresponding to the display brightness value DBV(x) to be compensated. (x)EM_step represents the minimum pulse width change after processing the low-level input signal in the light emission start signal. The remainder obtained after dividing the two signals (EM_step and EM_step) is the gamma level index corresponding to the display brightness value DBV(x) to be compensated. Finally, a lookup table of gamma index values ​​and gamma compensation values ​​is preset in the driver chip. This table allows for a one-to-one correspondence between the gamma index value and the gamma compensation value. By looking up this table, the gamma level offset corresponding to the gamma level index value can be obtained, thus achieving the gamma brightness compensation effect for the display brightness value DBV(x).

[0091] In some alternative embodiments, please continue to refer to the references. Figures 2-5 and Figure 9 , Figure 9 yes Figure 5 A circuit block diagram of the driver chip is shown in this embodiment. Figure 2 The display device 111 of the brightness compensation method in the embodiment includes a driver chip 30; the driver chip 30 integrates a gamma preset value generation circuit 301, a gamma compensation value generation circuit 302, and a gamma register 303;

[0092] The gamma preset value generation circuit 301 is configured to generate a gamma preset value, Gamma Level.

[0093] The gamma compensation value generation circuit 302 is configured to generate a gamma compensation value, Gamma Level offset.

[0094] The outputs of both the gamma preset value generation circuit 301 and the gamma compensation value generation circuit 302 are electrically connected to the gamma register 303.

[0095] This embodiment explains that the above-mentioned brightness compensation method can be executed by integrating a gamma preset value generation circuit 301 and a gamma compensation value generation circuit 302 in the driver chip 30. The gamma preset value generation circuit 301 is a module structure typically integrated in driver chips 30. In existing technologies, the gamma preset value generation circuit 301 generates a gamma preset value (GammaLevel) and directly outputs it to the gamma register 303, which then adjusts the display brightness. This embodiment adds an integrated gamma compensation value generation circuit 302 to the driver chip 30. The gamma compensation value generation circuit 302 is configured to be used to adjust the display brightness according to... Figure 2The brightness compensation method of the embodiment generates a gamma compensation value, Gamma Level offset, which is then superimposed on the gamma preset value Gamma Level generated by the gamma preset value generation circuit 301 and the gamma compensation value Gamma Level offset generated by the gamma compensation value generation circuit 302 and fed into the gamma register 303 from their respective output terminals to complete the brightness compensation during the dimming process and improve the display quality.

[0096] Optional, such as Figures 2-9 , Figure 10 As shown, Figure 10 Is adopted Figure 2 A comparison diagram of the positions of the gamma compensation value fine-tuning step points and the original brightness points after the brightness compensation method. Figure 1 and Figure 10 In this context, Lum represents the display brightness of a prior art display device (i.e., the display brightness variation trend without the brightness compensation method of this embodiment). Figure 4 In this context, Lum represents the display brightness of the display device in this embodiment (i.e., the trend of display brightness change after adopting the brightness compensation method of this embodiment). Figure 10 In this context, "Gamma Level offset" represents the fine-tuning step point after applying gamma compensation. Figure 10 As can be seen, by using the brightness compensation method of this embodiment, the gamma compensation value can be finely adjusted to reduce the actual display brightness from... Figure 1 Become Figure 4 This improves the smoothness of brightness changes across the entire screen, thereby enhancing display quality and mitigating sudden brightness changes.

[0097] Optionally, in this embodiment, the gamma preset value generation circuit 301 generates a gamma preset value based on the preset grayscale of the image to be displayed. That is, by inputting the image to be displayed, the preset grayscale of the image can be obtained, and then the gamma preset value corresponding to the preset grayscale is generated. It is understood that this embodiment does not elaborate on the principle of the gamma preset value generation circuit 301 generating the gamma preset value Gamma Level; for details, please refer to the dimming methods in related technologies for understanding.

[0098] Optionally, the brightness compensation method provided in this embodiment achieves the same accuracy of the actual gamma value change as the accuracy of all display brightness values ​​within the target display brightness value range. This embodiment explains that after using the above brightness compensation method, the accuracy of the change of all display brightness values ​​within the target display brightness value range is 12 bits, with a range of 2. 12That is, with a variation accuracy of 0-4095, the actual gamma value presented in the final gamma register 301 in this embodiment can also achieve a variation accuracy of 12 bits. This makes it possible to make the variation accuracy of the actual gamma value after compensation consistent with the variation accuracy of all display brightness values ​​in the target display brightness value range. This achieves the effect of optimizing the brightness variation accuracy and improves the problem of brightness abrupt changes caused by the variation accuracy of the duty cycle of the light emission control signal being less than the variation accuracy of DBV (Display Brightness Value). This is beneficial to improving display quality.

[0099] In some alternative embodiments, please continue to refer to the references. Figure 2 and Figure 5 This embodiment provides a chip 00, which can optionally be a driver chip 30. It can be bonded to the non-display area of ​​the display panel 000 via a flexible circuit board to form a display device 111 with the display panel 000. The chip 00 in this embodiment can also be a display driver IC (DDIC). This embodiment 00 is used to execute the brightness compensation method of any of the above embodiments, thereby improving the problem of sudden changes in display brightness and improving display quality.

[0100] In some alternative embodiments, please continue to refer to the references. Figure 2 and Figure 5 This embodiment provides a display device 111, which performs brightness compensation using any of the brightness compensation methods described in the above embodiments. It is understood that the display device 111 provided in this embodiment can be any other display device 111 with display functions, such as a computer, television, or vehicle-mounted display device; the present invention does not impose specific limitations on this. The display device 111 provided in this embodiment, after employing the brightness compensation method described in any of the above embodiments, has the beneficial effects provided by this embodiment. For details, please refer to the specific descriptions of the brightness compensation methods for the display devices in the above embodiments; these will not be repeated here.

[0101] It should 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 a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, 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 process, method, article, or apparatus that includes said element.

[0102] The above description is merely a specific embodiment of this disclosure, enabling those skilled in the art to understand or implement it. 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 disclosure. Therefore, this disclosure is not to be limited to the embodiments described herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A brightness compensation method for a display device, characterized in that, include: Get the gamma preset value; Obtain the display brightness value to be compensated and the offset value of the difference between the input and output of the illumination control signal; Based on the input and output difference offset values ​​of the light emission control signal and the display brightness value to be compensated, the pulse width of the light emission start signal before processing the low-level input signal is generated through the brightness control table; the minimum change pulse width of the low-level input signal after processing is obtained, and the gamma index value is calculated through the gamma index value calculation module based on the pulse width of the low-level input signal before processing in the light emission start signal; where Gamma Level Index = EM_Low_In%EM_step, Gamma Level Index represents the gamma index value, EM_Low_In represents the pulse width of the low-level input signal before processing in the light emission start signal corresponding to the display brightness value to be compensated, and EM_step represents the minimum change pulse width of the low-level input signal after processing in the light emission start signal; The gamma compensation value corresponding to the gamma index value is obtained by using a preset lookup table of gamma index value and gamma compensation value relationship. The preset gamma value and the gamma compensation value are output together as the actual gamma value corresponding to the display brightness value to be compensated.

2. The brightness compensation method for a display device according to claim 1, characterized in that, The display device further includes a display panel, which includes an electrically connected light-emitting control circuit and a light-emitting module. The light-emitting control circuit is used to provide a light-emitting control signal to the light-emitting module. Before obtaining the display brightness value to be compensated, the method further includes determining a target display brightness value range, which includes multiple display brightness value nodes. Different display brightness value nodes correspond to different low-level pulse width duty cycles of the light emission control signal. The display brightness value to be compensated is located between two adjacent display brightness value nodes.

3. The brightness compensation method for a display device according to claim 2, characterized in that, Based on the input and output difference offset value of the light emission control signal and the display brightness value to be compensated, the pulse width of the low-level input signal in the light emission start signal before processing is generated through the brightness control table, including: The brightness control table is based on linear interpolation to interpolate and calculate the pulse width of the low-level input signal in the light emission start signal before processing, corresponding to the brightness value to be compensated.

4. The brightness compensation method for a display device according to claim 3, characterized in that, The target display brightness value range includes adjacent first display brightness value nodes and second display brightness value nodes, and the display brightness value to be compensated is located between the first display brightness value node and the second display brightness value node; The brightness control table is based on linear interpolation to obtain the first pulse width corresponding to the first display brightness value node and the second pulse width corresponding to the second display brightness value node. Based on the first pulse width, the second pulse width, and the difference offset value between the input and output of the light emission control signal, the third pulse width corresponding to the display brightness value to be compensated is calculated using a linear interpolation formula. Wherein, the first pulse width is the pulse width of the light emission start signal corresponding to the first display brightness value node before the low-level input signal is processed, the second pulse width is the pulse width of the light emission start signal corresponding to the second display brightness value node before the low-level input signal is processed, and the third pulse width is the pulse width of the light emission start signal corresponding to the display brightness value to be compensated before the low-level input signal is processed.

5. The brightness compensation method for a display device according to claim 4, characterized in that, The linear interpolation calculation formula is as follows: EM_Low_In node (x) =Linear Interpoltatin (DBV node (n) ,EM_Low_In node (n) ,DBVnode (n+1) ,EM_Low_In node (n+1) ,DBV (x) )+EM_Low_Offset; Among them, DBV (x) For the display brightness value to be compensated, EM_Low_In node (x) For the third pulse width, DBVnode (n) For the first display brightness value node, EM_Low_In node (n) For the first pulse width, DBV node (n+1) For the second display brightness value node, EM_Low_In node (n+1) The second pulse width is EM_Low_Offset, which is the offset value between the input and output of the light emission control signal.

6. The brightness compensation method for a display device according to claim 1, characterized in that, The display device includes a driver chip; the driver chip integrates a gamma preset value generation circuit, a gamma compensation value generation circuit, and a gamma register. The gamma preset value generation circuit is configured to generate the gamma preset value, and the gamma compensation value generation circuit is configured to generate the gamma compensation value. The outputs of both the gamma preset value generation circuit and the gamma compensation value generation circuit are electrically connected to the gamma register.

7. The brightness compensation method for a display device according to claim 6, characterized in that, The gamma preset value generation circuit generates the gamma preset value based on the preset grayscale of the image to be displayed.

8. The brightness compensation method for a display device according to claim 2, characterized in that, The accuracy of the change in the actual gamma value is consistent with the accuracy of the change in all display brightness values ​​within the target display brightness value range.

9. A chip, characterized in that, The chip is used to perform the brightness compensation method according to any one of claims 1-8.

10. A display device, characterized in that, The display device performs brightness compensation using the brightness compensation method described in any one of claims 1-8.

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