Display panel, brightness compensation method thereof and display driving chip

Abstract

The application provides a display panel, a brightness compensation method thereof and a display driving chip, and solves the problem of uneven brightness of the same gray scale display screen in the prior art. The display panel comprises a display area, the display area comprises a plurality of sub-display areas, and the brightness compensation method comprises the following steps: acquiring a voltage drop of the display area, a screen body current of the display area and a resistance of any sub-display area; determining an actual display brightness of any sub-display area based on the voltage drop, the screen body current, the resistance of any sub-display area and a preset relationship model: Lum n ∝(K‑I*R n ) 2 , determining an actual display brightness of any sub-display area; determining a brightness compensation value of each sub-display area based on the actual display brightness of the sub-display area; and performing brightness compensation on the sub-display area based on the brightness compensation value. The phenomenon of overcompensation of brightness is almost not present.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of display, in particular to a display panel, a brightness compensation method thereof and a display driving chip. BACKGROUND

[0002] The voltage in the ELVDD metal line gradually decreases in the direction away from the display driving chip due to the voltage division caused by the resistance of the ELVDD metal line in the display panel, which leads to the non-uniformity of the ELVDD voltage in the entire display panel, and further leads to the non-uniformity of the brightness of the display screen of the same gray scale. SUMMARY

[0003] Therefore, the embodiments of the present application provide a brightness compensation method of a display panel, which solves the problem of the non-uniformity of the brightness of the display screen of the same gray scale in the prior art.

[0004] The first aspect of the present application provides a brightness compensation method of a display panel, the display panel comprising a display area, the display area comprising a plurality of sub-display areas, the brightness compensation method comprising:

[0005] obtaining a voltage drop of the display area, a screen body current of the display area and a resistance of any sub-display area;

[0006] determining an actual display brightness of any sub-display area based on a preset relationship model Lum n ∝(K-I R n ) 2 , wherein Lum n is the actual display brightness of the nth sub-display area, R n is the resistance of the nth sub-display area, I is the screen body current, K is the voltage drop, n is the number of the sub-display areas, and n is an integer greater than or equal to 1;

[0007] determining a brightness compensation value of each sub-display area based on the actual display brightness of the sub-display area;

[0008] compensating the brightness of the sub-display area based on the brightness compensation value.

[0009] In one embodiment, the step of obtaining the voltage drop of the display area, the screen body current of the display area and the resistance of any sub-display area comprises:

[0010] obtaining a target display brightness of a predetermined area of the display area in full gray scale display, the voltage drop of the display area, the screen body current of the display area and the resistance of any sub-display area;

[0011] Preferably, the actual display brightness of any sub-display area is determined based on a preset relationship model Lum n ∝(K-I R n ) 2determining the actual display brightness of any sub-display area comprises:

[0012] based on the target display brightness, the voltage drop, the panel current, the resistance of any sub-display area, and a preset relationship model: Lum n / L1=(K-I R n ) 2 / K 2 determining the actual display brightness of any sub-display area, wherein L1 is the target display brightness;

[0013] Preferably, the step of obtaining the target display brightness of the predetermined area of the display area in full gray scale display comprises:

[0014] obtaining the brightness of the center position of the display area in full gray scale display as the target display brightness;

[0015] Preferably, based on the actual display brightness of the sub-display area, determining the brightness compensation value of each sub-display area comprises:

[0016] based on the target display brightness and the actual display brightness of the sub-display area, determining the brightness compensation value of each sub-display area.

[0017] In one embodiment, based on the target display brightness and the actual display brightness of the sub-display area, determining the brightness compensation value of each sub-display area comprises:

[0018] determining the brightness compensation value of each sub-display area as the difference between the target display brightness and the actual display brightness.

[0019] In one embodiment, before obtaining the target display brightness of the predetermined area of the display area in full gray scale display, the brightness compensation method further comprises: performing global voltage drop compensation on the display panel.

[0020] In one embodiment, before the step of obtaining the target display brightness of the predetermined area of the display area in full gray scale display, further comprising:

[0021] measuring the actual display brightness of each sub-display area in full gray scale display;

[0022] based on the actual display brightness of each sub-display area, the panel current of the display area, the target display brightness, the voltage drop, and the relationship model, determining the resistance of each sub-display area;

[0023] Preferably, the step of obtaining the voltage drop of the display area comprises:

[0024] obtaining the power supply voltage and the data voltage of the display panel, and determining the difference between the power supply voltage and the data voltage as the voltage drop of the display area;

[0025] Preferably, the panel current is proportional to the average display brightness of the display area, and the step of obtaining the panel current of the display area comprises:

[0026] obtaining the average display brightness of the display area;

[0027] determining the panel current based on the average display brightness.

[0028] In one embodiment, the step of compensating the brightness of the sub-display area based on the brightness compensation value comprises:

[0029] compensating the brightness of the sub-display area of the current frame based on the brightness compensation value of the sub-display area of the current frame; or

[0030] compensating the brightness of the sub-display area of the next frame based on the brightness compensation value of the sub-display area of the current frame.

[0031] The second aspect of the present application provides a display driving chip, which uses the above-mentioned brightness compensation method to compensate a display panel, the display panel comprising a display area, and the display driving chip comprising:

[0032] an in-plane current statistical module, configured to count the current flowing through the display area;

[0033] a first compensation module, connected to the in-plane current statistical module, configured to compensate the brightness of the display area.

[0034] In one embodiment, the display driving chip further comprises a second compensation module, configured to compensate the global voltage drop of the display panel.

[0035] In one embodiment, the first compensation module and the second compensation module are combined into one compensation module.

[0036] The third aspect of the present application provides a display panel, which comprises the above-mentioned display driving chip.

[0037] The inventors of the present application consider the resistance in the ELVDD metal line, establish a corresponding relationship model between the actual display brightness of each sub-display area and the voltage drop of the display area, the panel current of the display area and the resistance of the sub-display area, can determine the actual display brightness of each sub-display area according to the relationship model, and further determine the brightness compensation value of each sub-display area based on the actual display brightness of each sub-display area. The brightness compensation of each sub-display area is more accurate, and the phenomenon of over-compensation of brightness is almost not present. Moreover, the brightness compensation method of the present application is not affected by the display background, and can accurately compensate the brightness for any display picture. BRIEF DESCRIPTION OF DRAWINGS

[0038] Figure 1 FIG. 1 is a structural schematic diagram of a display panel in one embodiment of the present application.

[0039] Figure 2 A flowchart of a brightness compensation method of a display panel in one embodiment of the present application.

[0040] Figure 3 A diagram of the relationship between pixel display brightness and pixel current in one embodiment of the present application.

[0041] Figure 4 A flowchart of a brightness compensation method of a display panel in another embodiment of the present application.

[0042] Figure 5 A flowchart of a brightness compensation method of a display panel in another embodiment of the present application.

[0043] Figure 6 A flowchart of a brightness compensation method of a display panel in another embodiment of the present application.

[0044] Figure 7 A structural diagram of a display driving chip in one embodiment of the present application.

[0045] Figure 8 A structural diagram of a display driving chip in another embodiment of the present application.

[0046] Figure 9 A structural diagram of a display driving chip in another embodiment of the present application. DETAILED DESCRIPTION

[0047] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of the present application.

[0048] In addition, in order to better illustrate the present application, numerous specific details are given in the following detailed description. Those skilled in the art should understand that the present application can also be implemented without some specific details. In some examples, methods and means familiar to those skilled in the art are not described in detail, in order to highlight the main ideas of the present application.

[0049] It should be noted that: similar reference numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0050] In addition, if the terms "first", "second", etc. are used, they are only used to distinguish description, and cannot be understood as indicating or implying relative importance.

[0051] The voltage in the ELVDD metal line gradually decreases in the direction away from the display driving chip due to the voltage division caused by the resistance of the ELVDD metal line, which is referred to as local IR drop (LIR), and the local IR drop can cause display unevenness, and therefore, compensation needs to be made for the local IR drop. The current local IR drop compensation scheme generally obtains single gray scale in-plane brightness data, determines the average brightness of each region and the average target brightness when 255 gray scale is displayed, and the brightness compensation value of each region is the difference between the average brightness of each region and the average target brightness. This compensation method is prone to overcompensation of the brightness of local regions and cannot solve the problem of display unevenness.

[0052] Therefore, the first aspect of the present application provides a brightness compensation method for a display panel. Referring to the structural schematic diagram of the display panel shown in Figure 1 The display panel 100 includes a display area 110, which includes a plurality of sub-display areas 111. Referring to the flowchart of the brightness compensation method shown in Figure 2 The brightness compensation method includes the following steps.

[0053] S100: Obtain the voltage drop of the display area, the screen body current of the display area, and the resistance of any sub-display area.

[0054] It should be noted that the screen body current is equal to the sum of the currents of all pixels.

[0055] It can be understood that the plurality of sub-display areas 111 can be arranged in an array, for example, the display area 110 can be divided into 9 sub-display areas 111, and the 9 sub-display areas 111 can be arranged in a 3 3 array; for example, the display area 110 can also be divided into 25 sub-display areas 111, and the 25 sub-display areas 111 can be arranged in a 5 5 array; the number of sub-display areas can be flexibly selected according to actual conditions.

[0056] In one embodiment, the step of obtaining the voltage drop of the display area, the screen body current of the display area, and the resistance of any sub-display area includes: obtaining the target display brightness of a predetermined region of the display area when full gray scale is displayed, the voltage drop of the display area, the screen body current of the display area, and the resistance of any sub-display area.

[0057] In one embodiment, obtaining the target display brightness of a predetermined region of the display area when full gray scale is displayed includes: obtaining the brightness of the center position of the display area when full gray scale is displayed as the target display brightness. In this way, the brightness of the center position of the display area when full gray scale is displayed is taken as the target display brightness, and the subsequently obtained brightness compensation value is more accurate, which is beneficial to avoid overcompensation of the brightness.

[0058] In one embodiment, the screen current is proportional to the average display brightness of the display area, and the screen current of the display area is obtained by: obtaining the average display brightness of the display area; and determining the screen current based on the average display brightness. As shown in the relationship between the pixel current and the display brightness Figure 3 The screen current can be determined based on the relationship curve between the pixel current and the display brightness and the average display brightness.

[0059] It should be noted that the average display brightness is equal to the sum of the brightness of all pixels.

[0060] In one embodiment, referring to the flowchart of the brightness compensation method shown in Figure 4 Before obtaining the target display brightness of the predetermined area of the display area when displaying in full gray scale, the method further includes the following steps.

[0061] S110: measuring the actual display brightness of each sub-display area when displaying in full gray scale.

[0062] S120: determining the resistance of each sub-display area based on the actual display brightness of each sub-display area, the screen current of the display area, the target display brightness, the voltage drop, and the relationship model.

[0063] In one embodiment, the voltage drop of the display area is obtained by: obtaining the power voltage and the data voltage of the display panel, and determining the difference between the power voltage and the data voltage as the voltage drop of the display area.

[0064] It can be understood that the target display brightness and the resistance of each sub-display area can be pre-stored in the display panel, and can be directly called when brightness compensation is needed.

[0065] S200: determining the actual display brightness of any sub-display area based on the voltage drop, the screen current, the resistance of any sub-display area, and the preset relationship model Lum n ∝(K-I R n ) 2 .

[0066] Wherein, Lum n is the actual display brightness of the nth sub-display area, R n is the resistance of the nth sub-display area, I is the screen current, K is the voltage drop, and n is the number of sub-display areas, n is an integer greater than or equal to 1.

[0067] It can be understood that the above relationship model can be pre-stored in the display panel, and can be directly called when brightness compensation is needed, which is simple, convenient, and easy to implement.

[0068] In one embodiment, the voltage drop, the screen current, the resistance of any sub-display area, and the preset relationship model Lumn α(K-I R n ) 2 , the step of determining the actual display brightness of any sub-display area comprises: based on the target display brightness, the voltage drop, the panel current, the resistance of any sub-display area, and a preset relationship model: Lum n / L1=(K-I R n ) 2 / K 2 , determining the actual display brightness of any sub-display area, wherein L1 is the target display brightness, and α represents a mathematical symbol proportional to.

[0069] The main factor affecting the LIR effect of the same gray scale under different backgrounds is still the panel current; from the pixel circuit current formula: I ds = μC ox (ELVDD-Vdata-|Vth|) 2 , wherein ELVDD is the power supply voltage, W and L are the width and length of the driving transistor channel respectively, μ is the effective carrier mobility, C ox is the unit area capacitance of the gate oxide layer, Vdata is the data voltage, and Vth is the threshold voltage of the driving transistor. It can be obtained that the pixel current is proportional to (ELVDD-Vdata) 2 , and the expression is pixel current α (ELVDD-Vdata) 2 . The relationship diagram of pixel current and pixel display brightness is shown in Figure 4 , and the pixel display brightness is proportional to the pixel current, so that the pixel display brightness Lum α pixel current α (ELVDD-Vdata) 2 , and the pixel display brightness α (ELVDD-Vdata) 2 .

[0070] The present inventors have found through a large amount of research that: 1. Due to the ELVDD metal line resistance, there is a voltage drop △ELVDD of the power supply voltage at different positions of the display area, so that the actual power supply voltage at different positions is ELVDD-△ELVDD, thereby obtaining the pixel display brightness Lum α pixel current α (ELVDD-△ELVDD-Vdata) 2 at different positions. The inventors found that the voltage drop △ELVDD of the power supply voltage at different positions is the panel current I R (the in-plane resistance at this location), thus obtaining the following relationship: the voltage drop of the power supply ΔELVDD ∝ the screen current I. 2. When displaying the same grayscale, ELVDD and Vdata are constants, represented by the constant K, where ELVDD-Vdata is represented. The in-plane line resistance R (the in-plane line resistance R is the resistance of the ELVDD line) at the same location in the display area is approximately constant as well. The pixel display brightness Lum at the same location ∝ (ELVDD-ΔELVDD−Vdata). 2 ∝(KI R) 2 We get Lum∝(KI) R) 2 3. The brightness of a single pixel, Lum, is equal to the pixel current, I'. Therefore, the total screen current, I, is equal to the sum of all pixel currents, ∑I'. Since the current I' of each pixel is proportional to its brightness, Lum, and the total screen current, I, is proportional to the sum of all pixel brightness, ∑Lum equals the average brightness, the total screen current, I, is proportional to the average brightness. Thus, the relationship is: Screen current I ∝ ∑Lum. 4. At different locations, the display brightness, Lum, is equal to (KI... R) 2 The display brightness is obtained as Lum∝(K'-∑Lum) R) 2 The in-plane line resistance R depends on the position; K is a constant across the entire screen. Since the screen current I∝∑Lum, the ratio of ∑Lum to I is equal to the ratio of K' to K, i.e., K'=K. ∑Lum / I, K' is also a constant. Based on the inventor's above research, the inventor will set the resistance R of any sub-display area... n Assuming it's a constant, the relationship between the actual display brightness, screen current, and resistance of any sub-display area is modeled as: Lum n ∝(KI R n ) 2 Meanwhile, Lum n ∝(K'-∑Lum R) 2 .

[0071] In one specific embodiment of this application, the brightness of the center position of the display area in full grayscale display is obtained as the target display brightness L1. At this time, the inventor sets the resistance at the center position to 0, and the target display brightness L1 at the center position is the actual display brightness, based on the above relationship model Lum. n ∝(KI R n ) 2 We obtain the following relation: L1∝K 2 .

[0072] In another specific embodiment of the present application, Lum n ∝(K’-∑Lum R) 2 , the target display brightness L1 of the center position is the actual display brightness, and the following relationship can be obtained: L1∝K’ 2 .

[0073] It can be understood that when the resistance of the center position of the display panel is set to 0, the resistance of different sub-display areas is relative to the resistance of the center position, that is, R n may be positive or negative in value.

[0074] In one specific embodiment, when full gray scale display, the actual display brightness and the screen current I of each sub-display area are measured, the target display brightness L1 is known, K is a constant, and the relationship model Lum n / L1=(K-I R n ) 2 / K 2 , the resistance R n of each sub-display area can be calculated.

[0075] In one specific embodiment, since the screen current I∝∑Lum, when full gray scale display, the actual display brightness of each sub-display area is measured, the target display brightness L1 is known, the average display brightness ∑Lum of the display area is the same size as L1, K’ is a constant, and the relationship model Lum n / L1=(K’-∑Lum R n ) 2 / K’ 2 , the resistance R n of each sub-display area can be calculated in proportion to K’, at this time, without calculating the specific value of the resistance R n of each sub-display area, the calculation process is simplified.

[0076] S300: Determine the brightness compensation value of each sub-display area based on the actual display brightness of the sub-display area.

[0077] Optionally, determining the brightness compensation value of each sub-display area based on the actual display brightness of the sub-display area includes: determining the brightness compensation value of each sub-display area based on the target display brightness and the actual display brightness of the sub-display area.

[0078] In one embodiment, determining the brightness compensation value of each sub-display area based on the target display brightness and the actual display brightness of the sub-display area comprises: determining the brightness compensation value of each sub-display area as the difference between the target display brightness and the actual display brightness.

[0079] S400: brightness compensation is performed on the sub-display area based on the brightness compensation value.

[0080] In one embodiment, the brightness compensation performed on the sub-display area based on the brightness compensation value comprises: compensating the brightness of the sub-display area of the current frame based on the brightness compensation value of the sub-display area of the current frame.

[0081] In another embodiment, the brightness compensation performed on the sub-display area based on the brightness compensation value comprises: compensating the brightness of the sub-display area of the next frame based on the brightness compensation value of the sub-display area of the current frame.

[0082] The inventors of the present application consider the resistance in the ELVDD metal line, set the resistance of each sub-display area as a constant value, and construct a relationship model: Lum n / L1=(K-I R n ) 2 / K 2 The actual display brightness of each sub-display area is established in correspondence with the target display brightness, the voltage drop of the display area, the screen current of the display area, and the resistance of the sub-display area, the actual display brightness of each sub-display area can be accurately determined, and then the brightness compensation value of each sub-display area is determined based on the target display brightness and the actual display brightness of each sub-display area, the brightness compensation of each sub-display area is more accurate, and the phenomenon of brightness overcompensation is almost not present; and the brightness compensation method of the present application is not affected by the display background, and accurate brightness compensation can be performed for any display picture.

[0083] In one embodiment, referring to the method flow diagram of brightness compensation shown in Figure 5 or Figure 6 Before obtaining the target display brightness of the predetermined area of the display area when displaying in full gray scale, the brightness compensation method further comprises the following steps.

[0084] S500: global voltage drop compensation is performed on the display panel.

[0085] After global voltage drop (GIR) compensation, the display panel brightness compensation effect is better, and the display picture uniformity is better.

[0086] In one specific embodiment, the display area is divided into 3 9 sub-display areas arranged in a 3

[0087] 1. Measure the target display brightness L1 at the center position of the display panel when displaying full gray scale, and the average display brightness ∑Lum=100% L1, the average display brightness can determine the screen body current, the line resistance of the 9 sub display areas is R1, R2, R3…R9 respectively, and the resistance at the center position is 0.

[0088] 2. Measure the actual display brightness Lum1, Lum2, Lum3…Lum9 of each sub display area, and use the relationship model Lum n / L1=(K-I R n ) 2 / K 2 to calculate the resistance of each sub display area, which is equivalent to the resistance at the center position. The resistance of the sub display area can be positive or negative in value.

[0089] 3. Measure the average display brightness ∑Lum of any display picture, and use the relationship model Lum n / L1=(K-I R n ) 2 / K 2 to calculate the actual display brightness Lum n ’ of each sub display area.

[0090] 4. Calculate the difference between the target display brightness L1 and the actual display brightness Lum n ’ of each sub display area, △Lum1’=L1-Lum1’, and determine the brightness compensation value based on the difference △Lum1’. Specifically, the brightness compensation value of each sub display area is determined as the difference △Lum1’ between the target display brightness and the actual display brightness.

[0091] 5. Perform brightness compensation on the sub display area based on the brightness compensation value.

[0092] For example, any sub display area is displayed at 255 gray scale, the remaining sub display areas are displayed at 0 gray scale, and the display area of the any sub display area accounts for 10% of the entire display area. The average display brightness ∑Lum of the display area is 10% L1, the average display brightness determines the screen body current I, and uses the relationship model Lum n / L1=(K-I R n ) 2 / K 2 to calculate the actual display brightness Lum n ’ of each sub display area. The brightness compensation value of each sub display area is △Lum1’, △Lum1’=L1-Lum n ’.

[0093] The second aspect of the present application provides a display driving chip, which uses the above-mentioned brightness compensation method to compensate a display panel, the display panel comprising a display area, the display driving chip comprising Figure 7 The structure diagram of the display driving chip is shown in FIG. 2, the display driving chip 200 comprising: an in-plane current statistical module, configured to count the current flowing through the display area; and a first compensation module, connected to the in-plane current statistical module, configured to compensate the brightness of the display area. Thus, the in-plane current statistical module is configured to count the pixel current of the display area, as described above, the pixel current is proportional to the pixel display brightness, and the relationship between the current and the display brightness can be established by counting the current, so that the display brightness of the display panel is compensated by using the above-mentioned brightness compensation method.

[0094] In one embodiment, referring to the structure diagram of the display driving chip shown in FIG. 2, the display driving chip further comprises: a second compensation module, configured to compensate the global voltage drop of the display panel. Figure 8

[0095] In one embodiment, referring to the structure diagram of the display driving chip shown in FIG. 2, the first compensation module and the second compensation module are combined into one compensation module. Figure 9

[0096] It can be understood that the display driving chip can further comprise a storage module, for example, a flash memory (FLASH) and a static random-access memory (SRAM), the flash memory and the static random-access memory being connected to the first compensation module respectively, the flash memory being configured to write and / or read the data in the aging compensation module; and the static random-access memory being configured to output the brightness compensation data to the display area.

[0097] It can be understood that the target display brightness L1, the resistance value of each sub-display area, and the target display brightness, the voltage drop, the panel current, the resistance of any sub-display area, and the preset relationship model: Lum n / L1=(K-I R n ) 2 / K 2 The data can be pre-stored in the display driving chip, and when brightness compensation is needed, the required data can be directly called.

[0098] The third aspect of the present application provides a display panel, comprising the above-mentioned display driving chip.

[0099] It can be understood that the display driving chip has the functions of the above-mentioned compensation function and the functions that a conventional display driving chip should have, which will not be described in detail here.​​

[0100] In one embodiment, the display panel includes a display area and a non-display area, the non-display area surrounds the display area, the display area is used to display a picture, and the display driving chip is arranged in the non-display area and is used to drive the display panel to display the picture in the display area. The display panel of the application has high picture uniformity.

[0101] Exemplarily, the display panel can be used to display a color picture or a black-and-white picture. Regardless of the type of the picture, the display panel of the application has high picture quality and good uniformity, and the picture quality is uniform and almost free of excessive brightness or excessive darkness.

[0102] Exemplarily, the type of the display panel is not particularly limited, and the display panel can be a mobile phone, a tablet computer, a smart watch, or the like. The display panel can be an OLED display panel or an LCD display panel.

[0103] It should be noted that, in addition to the display driving chip, the display panel also includes an array substrate, a pixel layer, an encapsulation structure, and other structures that should be included in a conventional display panel, which will not be described in detail here.

[0104] The application will be further described below in combination with specific embodiments. It should be noted that the following embodiments are only used to explain the application and cannot be understood as a limitation of the application.

[0105] Embodiment 1

[0106] The display area is divided into 3 9 sub-display areas arranged in an array, and the brightness compensation method of the display panel includes the following processes:

[0107] 1. The target display brightness of the display panel when displaying in full gray scale is L1, and the average display brightness ∑Lum=100%. L1, the screen body current can be determined according to the average display brightness, and the line resistances of the 9 sub-display areas are R1, R2, R3…R9, respectively.

[0108] 2. The actual display brightness of each sub-display area Lum1, Lum2, Lum3…Lum9 is measured, and the relationship model Lum n / L1=(K-I R n ) 2 / K 2 is used to calculate the resistance of each sub-display area, and n is 1, 2, 3…9.

[0109] 3. Any one sub-display area is displayed at 255 gray scale, the rest of the sub-display area is displayed at 0 gray scale, and the display area of the any one sub-display area accounts for 10% of the display area of the whole display area, and the average display brightness of the display area is ∑Lum=10% L1, the average display brightness can determine the screen current, using the relationship model Lum n / L1=(K-I R n ) 2 / K 2 , the actual display brightness Lum n ’ of each sub-display area is calculated, and the brightness compensation value of each sub-display area is △Lum1’, △Lum1’=L1-Lum n ’.

[0110] 4. The difference between the target display brightness L1 and the actual display brightness Lum n ’ of each sub-display area is calculated, △Lum1’=L1-Lum1’, and the brightness compensation value is determined based on the difference △Lum1’, and the size of the brightness compensation value is equal to △Lum1’.

[0111] 5. The brightness of the sub-display area is compensated based on the brightness compensation value.

[0112] The display brightness Lv of each sub-display area after compensation is obtained, and the brightness uniformity of the whole display area is calculated. The brightness compensation method of the embodiment can improve the brightness uniformity of the display picture to 97%.

[0113] Embodiment 2

[0114] The brightness compensation method of the display panel is basically the same as that of embodiment 1, and the difference is that before step 1, it further includes:

[0115] The global voltage drop compensation is performed on the display panel.

[0116] The display brightness Lv of each sub-display area after compensation is obtained, and the brightness uniformity of the whole display area is calculated. In this embodiment, the brightness compensation method combined with the global voltage drop compensation can improve the brightness uniformity of the display picture to 98%.

[0117] The basic principles of the present application are described above in combination with specific embodiments, but it should be pointed out that the advantages, advantages, effects and the like mentioned in the present application are only examples and not limitations, and these advantages, advantages, effects and the like cannot be considered as the must-have of each embodiment of the present application. In addition, the above specific details are only for the purpose of example and for the purpose of understanding, and are not limited to the above specific details. The above details do not limit the present application to be realized by the above specific details.

[0118] The foregoing description has been presented for purposes of illustration and description. Furthermore, this description is not intended to limit the embodiments of the application to the forms disclosed herein. Although various example aspects and embodiments have been discussed above, those of ordinary skill in the art will appreciate a variety of modifications, alternatives, permutations, additions, and sub-combinations of the described aspects and embodiments.

Claims

1. A brightness compensation method for a display panel, characterized in that, The display panel includes a display area, which in turn includes multiple sub-display areas. The brightness compensation method includes: Obtain the voltage drop of the display area, the screen current of the display area, and the resistance of any sub-display area; Based on the voltage drop, the screen current, the resistance of any sub-display area, and the preset relationship model Lum n ∝(KI R n ) 2 Determine the actual display brightness of any sub-display area, where Lum n R is the actual display brightness of the nth sub-display area. n Let I be the resistance of the nth sub-display area, I be the screen current, K be the voltage drop, and K equal to ELVDD-Vdata, n be the number of sub-display areas, and n be an integer greater than or equal to 1; Based on the actual display brightness of the sub-display areas, determine the brightness compensation value for each sub-display area; The brightness of the sub-display area is compensated based on the brightness compensation value; The step of obtaining the voltage drop of the display area, the screen current of the display area, and the resistance of any sub-display area includes: The target display brightness of a predetermined area of ​​the display area in full grayscale display, the voltage drop of the display area, the screen current of the display area, and the resistance of any sub-display area are obtained. The relationship is based on the voltage drop, the screen current, the resistance of any sub-display area, and the preset relationship model Lum. n ∝(KI R n ) 2 The steps for determining the actual display brightness of any sub-display area include: Based on the target display brightness, the voltage drop, the screen current, the resistance of any sub-display area, and a preset relationship model: Lum n / L1=(KI R n ) 2 / K 2 Determine the actual display brightness of any sub-display area, where L1 is the target display brightness; Before the step of obtaining the target display brightness of the predetermined area of ​​the display area when displayed in full grayscale, the method further includes: measuring the actual display brightness of each of the sub-display areas when displayed in full grayscale; and determining the resistance of each of the sub-display areas based on the actual display brightness of each of the sub-display areas, the screen current of the display area, the target display brightness, the voltage drop, and the relationship model. The step of obtaining the voltage drop of the display area includes: obtaining the power supply voltage and data voltage of the display panel, and determining the difference between the power supply voltage and the data voltage as the voltage drop of the display area; The screen current is proportional to the average display brightness of the display area. The step of obtaining the screen current of the display area includes: obtaining the average display brightness of the display area; and determining the screen current based on the average display brightness. The brightness compensation method is a brightness compensation method for the display panel under the same grayscale display screen.

2. The brightness compensation method according to claim 1, characterized in that, The step of obtaining the target display brightness of a predetermined area of ​​the display area in full grayscale display includes: The brightness of the center position of the display area in full grayscale display is obtained as the target display brightness.

3. The brightness compensation method according to claim 1, characterized in that, Based on the actual display brightness of the sub-display areas, the brightness compensation value for each sub-display area is determined as follows: Based on the target display brightness and the actual display brightness of the sub-display area, a brightness compensation value for each sub-display area is determined.

4. The brightness compensation method according to claim 3, characterized in that, Based on the target display brightness and the actual display brightness of the sub-display area, the brightness compensation value for each sub-display area is determined as follows: The brightness compensation value for each sub-display area is determined to be the difference between the target display brightness and the actual display brightness.

5. The brightness compensation method according to claim 1, characterized in that, Before obtaining the target display brightness of the predetermined area of ​​the display area in full grayscale display, the brightness compensation method further includes: performing global voltage drop compensation on the display panel.

6. The brightness compensation method according to claim 1, characterized in that, Performing brightness compensation on the sub-display area based on the brightness compensation value includes: Based on the brightness compensation value of the sub-display area in the current frame, the brightness of the sub-display area in the current frame is compensated; or, Based on the brightness compensation value of the sub-display area in the current frame, the brightness of the sub-display area in the next frame is compensated.

7. A display driver chip, characterized in that, The display panel is compensated using the brightness compensation method according to any one of claims 1 to 6, the display panel including a display area, and the display driver chip including: An in-plane current statistics module is used to count the current flowing through the display area; The first compensation module, connected to the in-plane current statistics module, is used to compensate for the brightness of the display area.

8. The display driver chip according to claim 7, characterized in that, Also includes: The second compensation module is used to perform global voltage drop compensation on the display panel.

9. The display driver chip according to claim 8, characterized in that, The first compensation module and the second compensation module are combined into one compensation module.

10. A display panel, characterized in that, Includes the display driver chip as described in any one of claims 7 to 9.

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