CN116381983A

CN116381983A - Luminance compensation method and device for display panel and display panel

Info

Publication number: CN116381983A
Application number: CN202211711252.6A
Authority: CN
Inventors: 王倩
Original assignee: TCL China Star Optoelectronics Technology Co Ltd
Current assignee: TCL China Star Optoelectronics Technology Co Ltd
Priority date: 2022-12-29
Filing date: 2022-12-29
Publication date: 2023-07-04
Anticipated expiration: 2042-12-29
Also published as: CN116381983B

Abstract

The method comprises the steps of firstly obtaining a first brightness difference curve along the horizontal direction and a second brightness difference curve along the vertical direction when a light-load picture and a heavy-load picture are respectively displayed on the display panel, then determining each partition point and a compensation partition according to each inflection point on the two curves, obtaining central point brightness compensation data and central point positions of the display panel, obtaining first brightness compensation data of each partition point by combining the first brightness difference curve, obtaining second brightness compensation data of each partition point by combining the second brightness difference curve, obtaining partition brightness compensation data by combining the two brightness compensation data, and finally carrying out brightness compensation on each compensation partition based on the central point brightness compensation data and the partition brightness compensation data. According to the method and the device, the partition points are determined through the inflection points on the brightness difference curve, the partition mode is matched with the charging characteristic, and the phenomenon of strip Mura is relieved.

Description

Luminance compensation method and device for display panel and display panel

Technical Field

The present disclosure relates to the field of display technologies, and in particular, to a brightness compensation method and device for a display panel, and a display panel.

Background

The large-sized UD resolution lcd panel is designed using a normal gate architecture as shown in fig. 1 (a) and a Tri-gate architecture as shown in fig. 2 (a). The liquid crystal display panel of the normal gate architecture comprises a plurality of red sub-pixels R, green sub-pixels G, blue sub-pixels B, D1, D2 and the like which are arranged in a vertical array, wherein the data lines are represented by G1, G2 and the like, each column of sub-pixels is connected with one data line, and each row of sub-pixels is connected with one scanning line. The liquid crystal display panel of the Tri-gate architecture comprises a plurality of red sub-pixels R, green sub-pixels G and blue sub-pixels B which are arranged in a transverse array manner, wherein each row of sub-pixels is connected with a scanning line, and each three rows of sub-pixels are connected with a data line. As shown in fig. 1 (b) and fig. 2 (b), the liquid crystal display panel 100 is connected to the driving circuit 300 through the flip-chip film 200, the source driving chips are disposed in the flip-chip film 200, 12 source driving chips are required for the liquid crystal display panel 100 of the normal gate architecture, and only 4 source driving chips are required for the liquid crystal display panel 100 of the Tri-gate architecture, so that the Tri-gate architecture has more cost advantage, and the industry is gradually invested in developing the Tri-gate architecture as a low cost solution.

Because the charging time of a single pixel in the Tri-gate architecture is only 1/3 of that of the normal gate architecture under the same condition, the charging time is seriously insufficient, so that the display brightness cannot reach the expected value. In addition, since there is a problem of RC delay (resistance capacitance delay) in the display panel, in-plane luminance unevenness is easily caused. In order to solve the problem of display brightness, each panel manufacturer adds a charge compensation function algorithm in a driving module such as a time sequence control board Tcon or a system-on-a-chip SOC, and the like, when the charge compensation algorithm is started, a central point brightness compensation data table LUT1 and a partition compensation brightness compensation data table LUT2 are required to be written so as to perform partition real-time compensation processing on video signals, and improve the screen display image quality, wherein the LUT1 records overdrive gray scale of a central point of a display panel and is used for overdrive compensation of the central point, the LUT2 records compensation coefficients of each partition point relative to the central point, and partition compensation can be performed according to the overdrive gray scale of the central point and the compensation coefficients.

Taking the normal gate structure liquid crystal display panel 100 of fig. 3 including 4 flip chip films 200 as an example, in the vertical direction, the charging effect is better in the region closer to the flip chip film 200, the charging effect is worse in the region farther from the flip chip film 200, and in the horizontal direction, the charging rate shows the effect shown in fig. 4 due to the periodic regularity of RC delay during panel charging, and x in fig. 4 ₁ To x ₄ Respectively correspond to the horizontal positions of the 4 flip chip films 200. Due to this regularity, the current scoreThe zone compensation scheme is equally spaced zone compensation, for example, the liquid crystal display panel 100 in fig. 3 is divided into 3*8 equally spaced compensation zones to compensate respectively. However, the scheme of equidistant partition is only suitable for normal gate architecture with no great difference in intra-area charging, when the Tri-gate architecture is adopted, because the charging is insufficient, the RC delay is serious and the period regularity is poor, the equidistant partition mode cannot be effectively matched with the actual charging characteristics, and different charging characteristics may exist for each pixel in the same compensation partition, then the compensation is performed based on the same compensation coefficient, so that the brightness of a part of pixels is too high or too low after the compensation, and the display panel has the phenomenon of strip Mura and the like, thereby influencing the display effect.

Therefore, the existing Tri-gate architecture display panel has the technical problem that the equidistant partition compensation mode is easy to cause strip Mura, and needs improvement.

Disclosure of Invention

The embodiment of the application provides a brightness compensation method and device for a display panel and the display panel, which are used for relieving the technical problem that the strip Mura occurs due to an equidistant partition compensation mode of the existing Tri-gate architecture display panel.

The embodiment of the application provides a brightness compensation method of a display panel, which comprises the following steps:

when a light-load picture and a heavy-load picture are respectively displayed on a display panel, a first brightness difference curve along the horizontal direction and a second brightness difference curve along the vertical direction are obtained, wherein data signals of sub-pixels in different rows in the light-load picture are the same, and data signals of sub-pixels in odd rows and data signals of sub-pixels in even rows in the heavy-load picture are different;

determining each partition point of the display panel according to each first inflection point on the first brightness difference curve and each second inflection point on the second brightness difference curve, and determining each compensation partition of the display panel according to each partition point position;

acquiring center point brightness compensation data and a center point position of the display panel;

obtaining first brightness differences between the partition points and the central point along the horizontal direction according to the central point positions, the partition point positions and the first brightness difference curves, and obtaining first brightness compensation data of the partition points according to the first brightness differences and the central point brightness compensation data; obtaining second brightness differences between the partition points and the central point along the vertical direction according to the central point positions, the partition point positions and the second brightness difference curves, and obtaining second brightness compensation data of the partition points according to the second brightness differences and the central point brightness compensation data;

And obtaining partition brightness compensation data of the display panel according to the first brightness compensation data and the second brightness compensation data of each partition point, and carrying out brightness compensation on each compensation partition of the display panel based on the center point brightness compensation data and the partition brightness compensation data.

In one embodiment, the step of obtaining a first luminance difference curve along a horizontal direction and a second luminance difference curve along a vertical direction when the display panel displays a light-load screen and a heavy-load screen, respectively, includes:

controlling the display panel to display a light-load picture, and collecting first horizontal brightness of a plurality of first sampling points in the horizontal direction and first vertical brightness of a plurality of second sampling points in the vertical direction in the light-load picture;

controlling the display panel to display a heavy-duty picture, and collecting second horizontal brightness of the first sampling points and second vertical brightness of the second sampling points in the heavy-duty picture;

obtaining horizontal brightness differences of the first sampling points according to the first horizontal brightness and the second horizontal brightness of the first sampling points, fitting to obtain a first brightness difference curve, obtaining vertical brightness differences of the second sampling points according to the first vertical brightness and the second vertical brightness of the second sampling points, and fitting to obtain a second brightness difference curve.

In one embodiment, the step of controlling the display panel to display the light-load picture includes:

controlling the display panel to display a light-load picture, wherein each row of sub-pixels in the light-load picture comprises a first display unit and a second display unit which are alternately arranged along the horizontal direction, each of the first display unit and the second display unit comprises at least one pixel, one of the first display unit and the second display unit displays a first gray scale, the other displays a second gray scale, and the difference value between the first gray scale and the second gray scale is larger than a threshold value;

the step of controlling the display panel to display the heavy-duty picture comprises the following steps:

and controlling the display panel to display a heavy-duty picture, wherein one of all odd-numbered row sub-pixels and all even-numbered row sub-pixels in the heavy-duty picture displays the first gray scale, and the other displays the second gray scale.

In one embodiment, before the step of collecting the first horizontal luminance of the plurality of first sampling points in the horizontal direction and the first vertical luminance of the plurality of second sampling points in the vertical direction in the light-load picture, the method further includes:

acquiring a horizontal central line and a vertical central line of the display panel;

And determining each first sampling point from the horizontal central line according to the first preset sampling precision, and determining each second sampling point from the vertical central line according to the second preset sampling precision.

In one embodiment, the step of determining each partition point of the display panel according to each first inflection point on the first luminance difference curve and each second inflection point on the second luminance difference curve includes:

acquiring first abscissas of i first inflection points on the first brightness difference curve and second abscissas of j second inflection points on the second brightness difference curve, wherein i and j are positive integers;

determining i partition abscissas according to the i first abscissas, and determining j partition abscissas according to the j second abscissas;

and determining i x j partition points of the display panel according to the i partition abscissas and the j partition ordinates.

In one embodiment, the step of determining each compensation zone of the display panel based on each zone point location comprises:

determining a horizontal partition line passing through each row of partition points and a vertical partition line passing through each column of partition points according to the positions of each partition point;

and determining each compensation partition of the display panel according to each horizontal partition line and each vertical partition line.

In one embodiment, the step of obtaining the first luminance compensation data of each partition point according to each first luminance difference and the luminance compensation data of the center point includes:

obtaining first target brightness compensation data of each partition point according to the central point brightness compensation data, each first brightness difference and brightness difference coefficient;

according to the brightness compensation data of each central point and the first target brightness compensation data, a first target brightness compensation coefficient of each partition point relative to the central point is obtained, and each first target brightness compensation coefficient is determined to be the first brightness compensation data of each partition point;

obtaining second brightness compensation data of each partition point according to each second brightness difference and the brightness compensation data of the central point, wherein the second brightness compensation data comprises the following steps:

obtaining second target brightness compensation data of each partition point according to the center point brightness compensation data, each second brightness difference and brightness difference coefficient;

and obtaining second target brightness compensation coefficients of the partition points relative to the center points according to the brightness compensation data of the center points and the second target brightness compensation data, and determining the second target brightness compensation coefficients as the second brightness compensation data of the partition points.

In one embodiment, after the step of obtaining the partition luminance compensation data of the display panel, the method further includes:

and storing the center point brightness compensation data and the partition brightness compensation data into a driving module connected with the display panel.

The application also provides a brightness compensation device of a display panel, comprising:

the first acquisition module is used for acquiring a first brightness difference curve along the horizontal direction and a second brightness difference curve along the vertical direction when the display panel displays a light-load picture and a heavy-load picture respectively, wherein data signals of different rows of sub-pixels in the light-load picture are the same, and data signals of odd-numbered row sub-pixels and data signals of even-numbered row sub-pixels in the heavy-load picture are different;

the determining module is used for determining each partition point of the display panel according to each first inflection point on the first brightness difference curve and each second inflection point on the second brightness difference curve, and determining each compensation partition of the display panel according to each partition point position;

the second acquisition module is used for acquiring the center point brightness compensation data and the center point position of the display panel;

the first obtaining module is used for obtaining first brightness differences between each partition point and the central point along the horizontal direction according to the central point position, each partition point position and the first brightness difference curve, and obtaining first brightness compensation data of each partition point according to each first brightness difference and the central point brightness compensation data; obtaining second brightness differences between the partition points and the central point along the vertical direction according to the central point positions, the partition point positions and the second brightness difference curves, and obtaining second brightness compensation data of the partition points according to the second brightness differences and the central point brightness compensation data;

And the second obtaining module is used for obtaining the partition brightness compensation data of the display panel according to the first brightness compensation data and the second brightness compensation data of each partition point, and carrying out brightness compensation on each compensation partition of the display panel based on the center point brightness compensation data and the partition brightness compensation data.

The application also provides a display panel, which performs brightness compensation by the brightness compensation method described in any one of the above.

The beneficial effects are that: the method comprises the steps of firstly obtaining a first brightness difference curve along a horizontal direction and a second brightness difference curve along a vertical direction when a light-load picture and a heavy-load picture are respectively displayed on the display panel, then determining each partition point of the display panel according to each first inflection point on the first brightness difference curve and each second inflection point on the second brightness difference curve, determining each compensation partition of the display panel according to each partition point position, obtaining central point brightness compensation data and central point position of the display panel, obtaining first brightness difference between each partition point and the central point along the horizontal direction according to the central point position, each partition point position and the first brightness difference curve, and obtaining first brightness compensation data of each partition point according to each first brightness difference and central point brightness compensation data; obtaining second brightness differences between each partition point and the central point along the vertical direction according to the central point position, each partition point position and the second brightness difference curve, obtaining second brightness compensation data of each partition point according to each second brightness difference and the central point brightness compensation data, and finally obtaining partition brightness compensation data of the display panel according to the first brightness compensation data and the second brightness compensation data of each partition point, and carrying out brightness compensation on each compensation partition of the display panel based on the central point brightness compensation data and the partition brightness compensation data. According to the method and the device, the partition points are determined through the inflection points on the brightness difference curves, and then the compensation partition and the partition brightness compensation data are determined, so that all pixels in the same compensation partition have similar charging characteristics, when the same compensation partition is compensated based on the same compensation scheme, the situation that the brightness of one row (column) or a plurality of rows (column) of pixels is too high or too low after compensation is avoided, the partition mode is matched with the charging characteristics, and the phenomenon of strip Mura is relieved.

Drawings

Technical solutions and other advantageous effects of the present application will be made apparent from the following detailed description of specific embodiments of the present application with reference to the accompanying drawings.

FIG. 1 is a schematic diagram of a normal gate architecture in the prior art.

FIG. 2 is a flow chart of a prior art Tri-gate architecture.

Fig. 3 is a schematic diagram of a partition scheme of a display panel in the prior art.

FIG. 4 is a schematic diagram of the charging rate of a normal gate structure display panel according to the prior art.

Fig. 5 is a flowchart of a brightness compensation method of a display panel according to an embodiment of the present application.

Fig. 6 is a schematic diagram of a light-load screen in an embodiment of the present application.

Fig. 7 is a schematic diagram of a reloading screen in an embodiment of the present application.

Fig. 8 is a schematic diagram of a first luminance difference curve in an embodiment of the present application.

Fig. 9 is a schematic diagram of a partition scheme of a display panel according to an embodiment of the present application.

Fig. 10 is a schematic diagram of LUT1 in the embodiment of the present application.

Fig. 11 is a schematic diagram of LUT2 in an embodiment of the present application.

Fig. 12 is a schematic structural diagram of a brightness compensation device of a display panel according to an embodiment of the present application.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. It will be apparent that the described embodiments are only some, but not all, of the embodiments of the present application. All other embodiments, which can be made by those skilled in the art based on the embodiments herein without making any inventive effort, are intended to be within the scope of the present application.

In the description of the present application, it should be understood that the terms "center," "longitudinal," "transverse," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," etc. indicate or are based on the orientation or positional relationship shown in the drawings, merely for convenience of description and to simplify the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present application. Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more of the described features. In the description of the present application, the meaning of "a plurality" is two or more, unless explicitly defined otherwise.

In the description of the present application, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be mechanically connected, electrically connected or can be communicated with each other; can be directly connected or indirectly connected through an intermediate medium, and can be communicated with the inside of two elements or the interaction relationship of the two elements. The specific meaning of the terms in this application will be understood by those of ordinary skill in the art as the case may be.

In this application, unless expressly stated or limited otherwise, a first feature being "above" or "below" a second feature may include the first feature and the second feature being in direct contact, or may include the first feature and the second feature not being in direct contact but being in contact by another feature therebetween. Moreover, a first feature being "above," "over" and "on" a second feature includes the first feature being directly above and obliquely above the second feature, or simply indicating that the first feature is higher in level than the second feature. The first feature being "under", "below" and "beneath" the second feature includes the first feature being directly under and obliquely below the second feature, or simply means that the first feature is less level than the second feature.

The following disclosure provides many different embodiments or examples for implementing different structures of the present application. In order to simplify the disclosure of the present application, the components and arrangements of specific examples are described below. Of course, they are merely examples and are not intended to limit the present application. Furthermore, the present application may repeat reference numerals and/or letters in the various examples, which are for the purpose of brevity and clarity, and which do not in themselves indicate the relationship between the various embodiments and/or arrangements discussed. In addition, the present application provides examples of various specific processes and materials, but one of ordinary skill in the art may recognize the application of other processes and/or the use of other materials.

The embodiment of the application provides a brightness compensation method and device for a display panel and the display panel, which are used for relieving the technical problem that the equidistant partition compensation mode of the existing Tri-gate architecture display panel is easy to cause strip Mura.

As shown in fig. 5, a flowchart of a brightness compensation method for a display panel according to an embodiment of the present application is shown, where the method specifically includes:

s1: when the display panel displays a light-load picture and a heavy-load picture respectively, a first brightness difference curve along the horizontal direction and a second brightness difference curve along the vertical direction are obtained, data signals of different rows of sub-pixels in the light-load picture are the same, and data signals of odd-row sub-pixels and data signals of even-row sub-pixels in the heavy-load picture are different.

The display panel in the embodiment of the present application is a Tri-gate architecture liquid crystal display panel shown in fig. 2, and the brightness compensation method is implemented based on the row overdrive compensation principle and the partition compensation principle. The driving compensation principle is as follows: for the liquid crystal display panel, when a data signal on a data line needs to be switched from a gray level required by a previous row of sub-pixels to a target gray level required by a current row of sub-pixels, if only a target driving voltage corresponding to the target gray level of the current row of sub-pixels is given, the current row of sub-pixels cannot actually reach the target gray level due to slow response speed of liquid crystal inversion, but has a certain deviation, and at this time, if an overdrive voltage is given to the current row of sub-pixels, the overdrive voltage and the target driving voltage have a certain difference value, the liquid crystal inversion speed can be increased, so that the gray level of the current row of sub-pixels can reach the target gray level required in practice, and the process of inputting the overdrive voltage to enable the current row of sub-pixels to display the target gray level is the row overdrive compensation process. The partition compensation principle is as follows: because the problem of RC delay (resistor-capacitor delay) exists in the display panel, even if the same driving voltage is input, pixels at different positions of the display panel can display different gray scales, so that uneven brightness is caused, if the display panel is partitioned first, and compensation coefficients of each partition point relative to a central point, namely compensation proportion, are given, brightness compensation data of the central point of the display panel can be used as a reference, compensation of different degrees is carried out on each partition according to different compensation coefficients of different partition points, and finally the display brightness uniformity of the panel is realized.

As shown in fig. 6, the light-load screen includes a plurality of rows of red sub-pixels R, a plurality of rows of green sub-pixels G, and a plurality of rows of blue sub-pixels B alternately arranged along the vertical direction, and data signals of the sub-pixels in different rows in the light-load screen are the same, that is, gray scales of the nth sub-pixel in each row of sub-pixels are equal. When the display panel scans and displays a light-load picture line by line, the gray scale required to be displayed by the sub-pixels in the previous line is always the same as the gray scale required to be displayed by the sub-pixels in the next line, and the same data signals are always input to each data line, so that the turning angle of the liquid crystal is also unchanged, and the ideal gray scale can be displayed by each sub-pixel in each line without adopting an overdrive technology in the light-load picture.

As shown in fig. 7, in the heavy-duty screen, the data signals of the sub-pixels 103 in the odd-numbered lines and the data signals of the sub-pixels 104 in the even-numbered lines are different, that is, the gray scale displayed by the sub-pixels 103 in the odd-numbered lines is different from the gray scale displayed by the sub-pixels 104 in the even-numbered lines, when the display panel scans line by line, the liquid crystal turning angles of any two adjacent lines need to be changed, and the gray scale actually displayed by the sub-pixels in the next line in the scanning sequence when a specific driving voltage is input is different from the ideal gray scale, and a certain brightness compensation is required to be performed by adopting a line overdrive technology to display the ideal gray scale.

When the display panel displays a light-load picture and a heavy-load picture respectively, each position point along the horizontal direction has two different brightnesses, the difference value of the two brightnesses is the brightness difference of the current position point, as shown in fig. 8, the lower left corner of the display panel is taken as the origin of coordinates, and the horizontal position and the horizontal brightness difference are taken as the horizontal and vertical coordinates respectively, so that a first brightness difference curve along the horizontal direction can be obtained. Similarly, when the display panel displays the light-load picture and the heavy-load picture respectively, each position point along the vertical direction has two different brightnesses, the difference value of the two brightnesses is the brightness difference of the current position point, the lower left corner of the display panel is taken as the origin of coordinates O, and the vertical position and the vertical brightness difference are taken as the horizontal and vertical coordinates respectively, so that a second brightness difference curve along the vertical direction can be obtained.

In one embodiment, S1 specifically includes:

s11: the control display panel displays a light-load picture, and acquires first horizontal brightness of a plurality of first sampling points in the horizontal direction and first vertical brightness of a plurality of second sampling points in the vertical direction in the light-load picture.

Controlling the display panel to display a light-load picture, and photographing the light-load picture by using an optical instrument to obtain first horizontal brightness Lv of a plurality of first sampling points from left to right along the horizontal direction _x1 And a first vertical luminance Lv of a plurality of second sampling points from bottom to top in the vertical direction _y1 。

S12: and controlling the display panel to display a heavy-duty picture, and collecting second horizontal brightness of a plurality of first sampling points and second vertical brightness of a plurality of second sampling points in the heavy-duty picture.

Controlling the display panel to display a heavy-duty picture, and photographing the heavy-duty picture by using an optical instrument to obtain second horizontal brightness Lv of a plurality of first sampling points from left to right along the horizontal direction _x2 And a second vertical luminance Lv of a plurality of second sampling points from bottom to top in the vertical direction _y2 . The line overdrive (Line over driving, LOD) function of the display panel needs to be turned off at the time of photographing and capturing, that is, each line of sub-pixels in the display panel is displayed at the original driving voltage, not at the overdrive voltage.

S13: obtaining horizontal brightness differences of the first sampling points according to the first horizontal brightness and the second horizontal brightness of the first sampling points, fitting to obtain a first brightness difference curve, obtaining vertical brightness differences of the second sampling points according to the first vertical brightness and the second vertical brightness of the second sampling points, and fitting to obtain a second brightness difference curve.

For each first sampling point, the first horizontal brightness Lv _x1 And a second horizontal luminance Lv _x2 By subtracting, the horizontal luminance difference DeltaLv can be obtained _x . With the lower left corner of the display panel as the origin of coordinates, using x _w The axis represents the horizontal distance between each point in the display panel and the origin of coordinates, y _w The axis represents the horizontal brightness difference of each point in the display panel, a first coordinate system is established, and a plurality of first sampling points in the first coordinate system are fitted to obtain a first brightness difference curve f (x _w )＝y _w ＝△Lv _x ＝a ₁ +b ₁ x _w +c ₁ (x _w ) ² +...+k ₁ (x _w ) ^t T is less than or equal to 6. Similarly, for each second sampling point, its first vertical luminance Lv _y1 And a second vertical luminance Lv _y2 Subtracting them to obtain the vertical brightness difference DeltaLv _y . With the lower left corner of the display panel as the origin of coordinates, using x _h The axis represents the vertical distance between each point in the display panel and the origin of coordinates, y _h The axes represent the vertical brightness differences of the points in the display panel, a second coordinate system is established, and a plurality of second sampling points in the second coordinate system are fitted to obtain a second brightness difference curve f (x) _h )＝y _h ＝△Lv _y ＝a ₂ +b ₂ x _h +c ₂ (x _h ) ² +...+k ₂ (x _h ) ^t ，t≤6。

In one embodiment, as shown in fig. 6, when the display panel is controlled to display a light-load picture, each row of sub-pixels in the light-load picture includes a first display unit 101 and a second display unit 102 alternately arranged along a horizontal direction, where each of the first display unit 101 and the second display unit 102 includes at least one pixel, one of the first display unit 101 and the second display unit 102 displays a first gray level m, and the other displays a second gray level n, and a difference value between the first gray level m and the second gray level n is greater than a gray level threshold. As shown in fig. 7, when the control display panel displays a heavy-duty screen, one of all odd-numbered row sub-pixels and all even-numbered row sub-pixels in the heavy-duty screen displays a first gray scale m, and the other displays a second gray scale n.

The display modes of the sub-pixels in different rows in the light-load picture are the same, but if all the sub-pixels in each row of sub-pixels display the same gray scale, the whole picture can display solid colors, the brightness of the adjacent pixels can cause larger interference when the brightness is acquired, so that the brightness data is not accurate enough, the mode that the first display unit 101 and the second display unit 102 are alternately arranged can be adopted, the gray scale difference of the two display units is larger, the influence of the adjacent pixels on the brightness of the current first sampling point is smaller, the accuracy of the brightness data of the current first sampling point is higher, and the effect of subsequent compensation is better. For the heavy-duty picture, the gray scale difference between the sub-pixels in the odd lines and the sub-pixels in the even lines is also larger, and the accuracy of the brightness data of the second sampling point is improved.

In one embodiment, before collecting the brightness of each first sampling point and each second sampling point, the method further comprises:

s14: a horizontal center line and a vertical center line of the display panel are acquired.

S15: and determining each first sampling point from the horizontal central line according to the first preset sampling precision, and determining each second sampling point from the vertical central line according to the second preset sampling precision.

When the first sampling points are determined, the center point of the column is determined to be the first sampling point, and all the first sampling points are distributed on the horizontal center line of the display panel, and according to the difference of the first preset sampling precision, each column where the first sampling point is located can correspond to one column of sub-pixels, or can correspond to two or more columns of sub-pixels. Similarly, a whole row is formed by the points with the same vertical distance from the origin of coordinates in the display panel, when the second sampling points are determined, the center point of the row is determined to be the second sampling points, and all the second sampling points are distributed on the vertical center line of the display panel, and according to the difference of the second preset sampling precision, each row of the second sampling points can correspond to one row of sub-pixels, or can correspond to two or more rows of sub-pixels.

In the subsequent steps, the partition brightness compensation data is needed to be obtained by combining the brightness compensation data of the central point of the display panel, the first brightness difference curve and the second brightness difference curve, and the central point of the display panel is located on the horizontal central line and the vertical central line at the same time, so that each point on the horizontal central line is taken as a first sampling point to acquire the brightness data and establish the first brightness difference curve, each point on the vertical central line is taken as a second sampling point to acquire the brightness data and establish the second brightness difference curve, the deviation of sampling position factors on the brightness data can be reduced, and the accuracy of a final calculation result is improved.

S2: and determining each partition point of the display panel according to each first inflection point on the first brightness difference curve and each second inflection point on the second brightness difference curve, and determining each compensation partition of the display panel according to each partition point position.

The first brightness difference curve is used for representing the change trend of the charging characteristic of the display panel in the horizontal direction, the change trend is in various states such as ascending, descending or stable, when the states are changed, first inflection points exist in the first brightness difference curve, and a section of curve between two adjacent first inflection points shows a unified change trend. The judging condition of whether each point on the first brightness difference curve is a first inflection point is as follows: if at a certain point x _w Y of (2) _w "=0 and y _w ' ₊ ×y _w ' _- If less than 0, the first inflection point is a certain point x _w Y of (2) _w "noteq0, or y _w "=0 and y _w ' ₊ ×y _w ' _- Greater than 0, then not the first inflection point.

When a certain section of curve has a monotonically rising trend, the horizontal brightness difference delta Lv is shown in the horizontal position section corresponding to the section of curve _x With position x _w When a certain section of curve has a monotonically decreasing trend, the right shift of the curve gradually increases, and the horizontal brightness difference delta Lv is displayed in the horizontal position interval corresponding to the section of curve _x With position x _w Gradually decreasing right shift of (c). For a certain horizontal position interval with consistent change trend of the charging characteristics, if the same compensation coefficient is adopted for compensation, the brightness of each position point in the horizontal position interval after compensation is uniform, and the phenomenon that the brightness of a certain position point is obviously too high or too low to cause strip Mura is avoided. Therefore, how the division is performed in the horizontal direction can be determined from each first inflection point in the first luminance difference curve.

Similarly, the second brightness difference curve is used for representing the variation trend of the charging characteristic of the display panel in the vertical direction, the variation trend has various states such as rising, falling or stable, and when the states are changed, a second inflection point exists in the second brightness difference curve, and a section of curve between two adjacent second inflection points presents a uniform variation trend. The judging condition of whether each point on the second brightness difference curve is a second inflection point is as follows: if at a certain point x _h Y of (2) _h "=0 and y _h ' ₊ ×y _h ' _- If less than 0, the second inflection point is a certain point x _h Y of (2) _h "noteq0, or y _h "=0 and y _h ' ₊ ×y _h ' _- Greater than 0, then not the second inflection point.

When a certain section of curve has a monotonically rising trend, the vertical brightness difference delta Lv is shown in the vertical position interval corresponding to the section of curve _y With position x _h When a certain section of curve is in monotonous descending trend, the upward movement of the curve gradually increases, and the vertical brightness difference delta Lv is shown in the vertical position interval corresponding to the section of curve _y With position x _h Gradually decreasing upward movement of (c). For a certain vertical position interval with consistent charging characteristic change trend, if the same compensation coefficient is adopted for compensation, the brightness of each position point in the vertical position interval after compensation is uniform, and the phenomenon that the brightness of a certain position point is obviously too high or too low to cause strip Mura can not occur. Therefore, how the division is performed in the vertical direction can be determined from each second inflection point in the second luminance difference curve.

In one embodiment, the step of determining each partition point according to the first inflection point and the second inflection point may specifically include:

s21: and acquiring a first abscissa of i first inflection points on the first brightness difference curve and a second abscissa of j second inflection points on the second brightness difference curve, wherein i and j are positive integers.

S22: and determining i partition abscissas according to the i first abscissas, and determining j partition abscissas according to the j second abscissas.

S23: and determining i x j partition points of the display panel according to the i partition abscissas and the j partition ordinates.

As shown in fig. 8, i first inflection points on the first luminance difference curve are determined according to the above-mentioned first inflection point judgment conditions, and corresponding i first abscissa x are obtained _w1 To x _wi Simultaneously determining j first inflection points on a second brightness difference curve according to the judgment conditions of the second inflection points, and obtaining corresponding j second abscissa x _h1 To x _hj . And then, taking the lower left corner of the display panel as the origin of coordinates, using an x axis to represent the horizontal distance between each point in the display panel and the origin of coordinates, and using a y axis to represent the vertical distance between each point in the display panel and the origin of coordinates, and establishing a third coordinate system, wherein in the third coordinate system, the i first abscissas are respectively used as i partition abscissas of the partition points, and the j second abscissas are respectively used as j partition ordinates of the partition points, so that i×j partition points are obtained.

As shown in fig. 9, the liquid crystal display panel 100 is connected to a driving circuit 300 through a flip chip film 200. After determining how to partition in the horizontal direction and how to partition in the vertical direction, each partition point 11 in the display panel may be determined, each partition point 11 is distributed in an array in the display panel, according to the positions of each partition point, a horizontal partition line 110 passing through each row of partition points and a vertical partition line 120 passing through each column of partition points may be determined, the display panel may be divided into a plurality of rectangular small areas by the plurality of horizontal partition lines 110 and the plurality of vertical partition lines 120, each small area is one compensation partition 111, and since the positions of each partition point are determined according to the first inflection point and the second inflection point, the partition scheme is an irregular partition scheme, and the obtained sizes of the compensation partitions 111 are not exactly the same.

By the method, the change trend of the charging characteristics in each compensation partition is kept consistent, and each pixel in the same compensation partition has similar charging characteristics, so that the situation that the brightness of one row (column) or a plurality of rows (columns) of pixels is too high or too low after compensation is avoided when the same compensation partition is compensated based on the same compensation coefficient later, the partition mode is matched with the charging characteristics, and the phenomenon of strip Mura is relieved.

S3: and acquiring the center point brightness compensation data and the center point position of the display panel.

The display panel requires center-lighting luminance compensation data and partition-luminance compensation data when compensating based on the row overdrive principle and the partition compensation principle. The center point brightness compensation data exists in a Table form, which is called LUT1 (Look-Up Table 1), and LUT1 is used for recording overdrive gray scales of the center point of the display panel in each case. The partition luminance compensation data also exists in a Table format, which is called LUT2 (Look-Up Table 2), and LUT2 is used to record the luminance compensation coefficient of each partition point of the display panel with respect to the center point.

The LOD Table shown in fig. 10 is LUT1, in which the gray-scale binding point value of the previous row of sub-pixels in the display panel is horizontally recorded, the gray-scale binding point value of the current row of sub-pixels in the display panel is vertically recorded, the crossing position of the two records the overdrive gray-scale value of the current row of sub-pixels in this case, and on the diagonal, the overdrive gray-scale value is equal to the two gray-scale binding point values because the gray-scale binding point values of the previous row of sub-pixels and the current row of sub-pixels are equal. And recording corresponding overdrive gray scale values according to specific difference values of gray scale binding point values of the previous row of sub-pixels and the current row of sub-pixels corresponding to the positions at different positions on the non-diagonal line, wherein the overdrive voltage corresponding to the overdrive gray scale values can enable the current row of sub-pixels to display ideal target gray scales. In order to maintain the picture quality, it is necessary to ensure that the gray level of the center point of the display panel reaches the target gray level during compensation, and the data recorded in LUT1 are all used to provide compensation reference for the center point of the display panel.

The Gain Table shown in fig. 11 is LUT2, in which the number of pixel distributions of each partition point in the horizontal direction is transversely recorded, the number of pixel distributions of each partition point in the vertical direction is longitudinally recorded, the intersection position of the two records the brightness compensation coefficient of the current partition point relative to the center point, that is, the compensation proportion, and the compensation partition where the center point is located defaults to 100%. In the display panel, due to the influence of RC delay, gray scales at different positions of the display panel have certain difference, when the same driving voltage is adopted, the brightness of some areas is higher than the brightness of the central point, or the brightness of some areas is lower than the brightness of the central point, so that the brightness of the whole panel is uniform, the brightness compensation coefficient of each partition point relative to the central point needs to be recorded by taking the brightness of the central point as a reference, and then the compensation scheme of the corresponding compensation partition is determined according to the brightness compensation coefficient and a related algorithm. When the brightness compensation coefficient is greater than 100%, the driving voltage in the current compensation partition needs to be greater than the driving voltage of the central point to keep brightness consistent, and when the brightness compensation coefficient is less than 100%, the driving voltage in the current compensation partition needs to be less than the driving voltage of the central point to keep brightness consistent.

In this step, the center point luminance compensation data LUT1 of the display panel is obtained, and the center point position is obtained to obtain the abscissa x of the center point in the third coordinate system ₀ And the ordinate y ₀ . Wherein the abscissa x ₀ Corresponding to the abscissa x in the first coordinate system where the first brightness difference curve is located _w0 The ordinate y ₀ Corresponding to the abscissa x in the second coordinate system where the second brightness difference curve is located _h0 。

S4: obtaining first brightness differences between each partition point and the central point along the horizontal direction according to the central point position, each partition point position and a first brightness difference curve, and obtaining first brightness compensation data of each partition point according to each first brightness difference and the central point brightness compensation data; and obtaining second brightness differences between each partition point and the central point along the vertical direction according to the central point position, each partition point position and the second brightness difference curve, and obtaining second brightness compensation data of each partition point according to each second brightness difference and the central point brightness compensation data.

After the coordinates of the center point and the coordinates of the partition points are obtained, the horizontal brightness of the partition points and the horizontal brightness of the center point can be obtained on a first brightness difference curve, the horizontal brightness difference can be obtained by subtracting the two, the first brightness difference can reflect the difference of the required compensation degree of the partition points and the center point in the horizontal direction, and then the central brightness compensation data can be used as a reference and combined with the first brightness difference to calculate the first brightness compensation data. Similarly, the vertical brightness of each partition point and the vertical brightness of the central point can be obtained on the second brightness difference curve, the two can be subtracted to obtain a second brightness difference along the vertical direction, the second brightness difference can reflect the difference of the required compensation degree of each partition point and the central point along the vertical direction, and when the brightness compensation data of the central point are known, the second brightness compensation data can be obtained according to the second brightness difference of each partition point.

In one embodiment, the step of obtaining the first luminance compensation data of each compensation partition specifically includes:

s41: and obtaining first target brightness compensation data of each partition point according to the central brightness compensation data, each first brightness difference and the brightness difference coefficient.

S42: and obtaining first target brightness compensation coefficients of the partition points relative to the central points according to the brightness compensation data of the central points and the first target brightness compensation data, and determining the first target brightness compensation coefficients as the first brightness compensation data of the partition points.

The step of obtaining the second luminance compensation data of each compensation partition specifically includes:

s43: and obtaining second target brightness compensation data of each partition point according to the central brightness compensation data, each second brightness difference and the brightness difference coefficient.

S44: and obtaining second target brightness compensation coefficients of the partition points relative to the central points according to the brightness compensation data of the central points and the second target brightness compensation data, and determining the second target brightness compensation coefficients as the second brightness compensation data of the partition points.

The center point luminance compensation data, f (x) _wi ) Representing the luminance difference of each partition point on the first luminance difference curve, f (x _w0 ) Representing the brightness difference of the center point of the display panel on the first brightness difference curve, and k represents the brightness difference coefficient, the first target brightness compensation data V of each partition point _i The following conditions are satisfied:

since the LUT2 usually describes the compensation ratio, the first target brightness compensation coefficients V are calculated _i The LUT1 is the first luminance compensation data of each partition point.

According to the same calculation method, the second target brightness compensation data H of each partition point can be calculated _j Each second target brightness compensation coefficient H _j LUT1, regard every second goal luminance compensation coefficient as the second luminance compensation data of every partition point.

S5: and obtaining partition brightness compensation data of the display panel according to the first brightness compensation data and the second brightness compensation data of each partition point, and carrying out brightness compensation on each compensation partition of the display panel based on the central brightness compensation data and the partition brightness compensation data.

After the first brightness compensation data and the second brightness compensation data of each partition point are obtained, the first brightness compensation data and the second brightness compensation data are integrated and filled in the positions corresponding to the partition points in the LUT2, and then the partition brightness compensation data of the display panel are obtained. Then, the central lighting brightness compensation data LUT1 and the partition brightness compensation data LUT2 are stored in a driving module connected with the display panel, wherein the driving module can be a time sequence control board Tcon or a system level chip SOC, when the display panel is in a display state, required data are directly inquired from the LUT1 and the LUT2, calculation is performed through a corresponding charging compensation algorithm, and a compensation scheme of each compensation partition, namely data signals which should be input on each data line in each compensation partition, is determined according to a calculation result, so that the whole display panel achieves the expected brightness.

As shown in fig. 12, an embodiment of the present application further provides a brightness compensation device of a display panel, specifically including:

a first obtaining module 10, configured to obtain a first luminance difference curve along a horizontal direction and a second luminance difference curve along a vertical direction when the display panel displays a light-load picture and a heavy-load picture, where data signals of different rows of sub-pixels in the light-load picture are the same, and data signals of odd-numbered rows of sub-pixels and data signals of even-numbered rows of sub-pixels in the heavy-load picture are different;

a determining module 20, configured to determine each partition point of the display panel according to each first inflection point on the first luminance difference curve and each second inflection point on the second luminance difference curve, and determine each compensation partition of the display panel according to each partition point position;

a second obtaining module 30, configured to obtain center point brightness compensation data and a center point position of the display panel;

a first obtaining module 40, configured to obtain first luminance differences between each partition point and a central point along a horizontal direction according to the central point position, each partition point position, and the first luminance difference curve, and obtain first luminance compensation data of each partition point according to each first luminance difference and the central point luminance compensation data; obtaining second brightness differences between the partition points and the central point along the vertical direction according to the central point positions, the partition point positions and the second brightness difference curves, and obtaining second brightness compensation data of the partition points according to the second brightness differences and the central point brightness compensation data;

And a second obtaining module 50, configured to obtain partition luminance compensation data of the display panel according to the first luminance compensation data and the second luminance compensation data of each partition point, and perform luminance compensation on each compensation partition of the display panel based on the center point luminance compensation data and the partition luminance compensation data.

In one embodiment, the first acquisition module 10 comprises:

the first control sub-module is used for controlling the display panel to display a light-load picture and collecting first horizontal brightness of a plurality of first sampling points in the light-load picture along the horizontal direction and first vertical brightness of a plurality of second sampling points in the vertical direction;

the second control submodule is used for controlling the display panel to display a heavy-load picture and collecting second horizontal brightness of the first sampling points and second vertical brightness of the second sampling points in the heavy-load picture;

the fitting sub-module is used for obtaining the horizontal brightness differences of the first sampling points according to the first horizontal brightness and the second horizontal brightness of the first sampling points, fitting to obtain a first brightness difference curve, obtaining the vertical brightness differences of the second sampling points according to the first vertical brightness and the second vertical brightness of the second sampling points, and fitting to obtain a second brightness difference curve.

In one embodiment, the first control submodule is to: controlling the display panel to display a light-load picture, wherein each row of sub-pixels in the light-load picture comprises a first display unit and a second display unit which are alternately arranged along the horizontal direction, each of the first display unit and the second display unit comprises at least one pixel, one of the first display unit and the second display unit displays a first gray scale, the other displays a second gray scale, and the difference value between the first gray scale and the second gray scale is larger than a gray scale threshold value;

the second control submodule is used for: and controlling the display panel to display a heavy-duty picture, wherein one of all odd-numbered row sub-pixels and all even-numbered row sub-pixels in the heavy-duty picture displays the first gray scale, and the other displays the second gray scale.

In one embodiment, the first acquisition module 10 further comprises:

the first acquisition submodule is used for acquiring a horizontal central line and a vertical central line of the display panel;

and the first determining submodule is used for determining each first sampling point from the horizontal central line according to a first preset sampling precision and determining each second sampling point from the vertical central line according to a second preset sampling precision.

In one embodiment, the determining module 20 includes:

a second obtaining submodule, configured to obtain a first abscissa of i first inflection points on the first luminance difference curve and a second abscissa of j second inflection points on the second luminance difference curve, where i and j are positive integers;

the second determining submodule is used for determining i partition abscissas according to the i first abscissas and determining j partition abscissas according to the j second abscissas;

and the third determining submodule is used for determining i x j partition points of the display panel according to the i partition abscissa and the j partition ordinate.

In one embodiment, the determining module 20 includes:

a fourth determining submodule, configured to determine a horizontal partition line passing through each row of partition points and a vertical partition line passing through each column of partition points according to the location of each partition point;

and a fifth determining sub-module for determining each compensation zone of the display panel according to each horizontal zone line and each vertical zone line.

In one embodiment, the first deriving module 40 comprises:

the first obtaining submodule is used for obtaining first target brightness compensation data of each partition point according to the brightness compensation data of the central point, each first brightness difference and a brightness difference coefficient;

A sixth determining sub-module, configured to obtain, according to the luminance compensation data of each center point and the first target luminance compensation data, a first target luminance compensation coefficient of each partition point relative to the center point, and determine each first target luminance compensation coefficient as first luminance compensation data of each partition point;

a second obtaining sub-module, configured to obtain second target luminance compensation data of each partition point according to the luminance compensation data of the center point, each second luminance difference, and a luminance difference coefficient;

and a seventh determining sub-module, configured to obtain, according to the luminance compensation data of each center point and the second target luminance compensation data, a second target luminance compensation coefficient of each partition point relative to the center point, and determine each second target luminance compensation coefficient as the second luminance compensation data of each partition point.

In one embodiment, the second deriving module 50 further comprises:

and the storage module is used for storing the central point brightness compensation data and the partition brightness compensation data into a driving module connected with the display panel.

According to the brightness compensation device of the display panel, the partition points are determined through the inflection points on the brightness difference curves, and then the compensation partition and the partition brightness compensation data are determined, so that all pixels in the same compensation partition have similar charging characteristics, when the same compensation partition is compensated based on the same compensation scheme, the situation that brightness is too high or too low after one row (column) or a plurality of rows (columns) of pixels are compensated is avoided, and therefore the situation that an nonstandard partition mode is matched with the charging characteristics is achieved, and the phenomenon of strip Mura is relieved.

The embodiment of the application also provides a display panel, which performs brightness compensation by the brightness compensation method described in any one of the embodiments, and the display panel may be a large-sized UD display panel with various Tri-gate architectures. After the brightness compensation is performed in the mode, the in-plane brightness is uniform, the phenomenon of strip Mura is relieved, and the display effect is improved.

The embodiment of the application also provides a display device, which comprises a display panel and a driving module, wherein the display panel performs brightness compensation by the brightness compensation method according to any embodiment. The display panel can be a large-size UD display panel with various Tri-gate architectures, the driving module can be a time sequence control board Tcon or a system-on-chip SOC, after brightness compensation is carried out in the mode, the brightness in the plane is uniform, the phenomenon of strip Mura is relieved, and the display effect is improved.

In the foregoing embodiments, the descriptions of the embodiments are emphasized, and for parts of one embodiment that are not described in detail, reference may be made to related descriptions of other embodiments.

The foregoing describes in detail a luminance compensation method, a luminance compensation device, a display panel and a display device for a display panel provided in the embodiments of the present application, and specific examples are applied to illustrate the principles and embodiments of the present application, where the foregoing description of the embodiments is only for helping to understand the technical solution and core ideas of the present application; those of ordinary skill in the art will appreciate that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A brightness compensation method for a display panel, comprising:

2. The method of compensating brightness of a display panel according to claim 1, wherein the step of acquiring a first brightness difference curve in a horizontal direction and a second brightness difference curve in a vertical direction of the display panel when the display panel displays a light-load picture and a heavy-load picture, respectively, comprises:

3. The method of claim 2, wherein the step of controlling the display panel to display a light-load picture comprises:

controlling the display panel to display a light-load picture, wherein each row of sub-pixels in the light-load picture comprises a first display unit and a second display unit which are alternately arranged along the horizontal direction, each of the first display unit and the second display unit comprises at least one pixel, one of the first display unit and the second display unit displays a first gray scale, the other displays a second gray scale, and the difference value between the first gray scale and the second gray scale is larger than a gray scale threshold value;

4. The method of claim 2, further comprising, prior to the step of collecting first horizontal luminances of a plurality of first sampling points in a horizontal direction and first vertical luminances of a plurality of second sampling points in a vertical direction in the light-load picture:

5. The method of compensating for brightness of a display panel according to claim 1, wherein the step of determining each partition point of the display panel according to each first inflection point on the first brightness difference curve and each second inflection point on the second brightness difference curve comprises:

6. The method of compensating for brightness of a display panel according to claim 1, wherein the step of determining each compensation partition of the display panel according to each partition point position comprises:

7. The method of compensating brightness of a display panel according to claim 1, wherein the step of obtaining first brightness compensation data of each of the partition points based on each of the first brightness differences and the center point brightness compensation data comprises:

8. The method of luminance compensation of a display panel according to any one of claims 1 to 7, further comprising, after the step of obtaining the divided luminance compensation data of the display panel:

9. A brightness compensation device for a display panel, comprising:

10. A display panel characterized in that the display panel is brightness-compensated by the brightness compensation method according to any one of claims 1 to 8.