CN113284470B

CN113284470B - Public voltage compensation method and liquid crystal display device

Info

Publication number: CN113284470B
Application number: CN202110576025.6A
Authority: CN
Inventors: 曾德康; 胡水秀; 袁海江
Original assignee: HKC Co Ltd
Current assignee: HKC Co Ltd
Priority date: 2021-05-26
Filing date: 2021-05-26
Publication date: 2023-04-25
Anticipated expiration: 2041-05-26
Also published as: CN113284470A

Abstract

The application provides a common voltage compensation method and a liquid crystal display device, and relates to the technical field of display, wherein the common voltage compensation method comprises the following steps: when the driving mode of the display picture is dot inversion, column 2 dot inversion or row 2 dot inversion, determining whether the display picture belongs to a first type of display picture; when the display picture does not belong to the first type of display picture, determining the number of first target sub-pixels and second target sub-pixels in each row of sub-pixels; when the numbers of the first target sub-pixels and the second target sub-pixels are unequal, corresponding public voltage compensation values are determined and output according to the data voltages of the first target sub-pixels and the data voltages of the second target sub-pixels. According to the method and the device, whether the number of the positive and negative polarity sub-pixels is required to be determined is judged by determining the driving mode and the type of the display picture, and the corresponding common voltage compensation value is determined and compensated by the data voltage of the positive and negative polarity sub-pixels, so that the compensated display picture can be normally displayed.

Description

Public voltage compensation method and liquid crystal display device

Technical Field

The application belongs to the technical field of display, and particularly relates to a common voltage compensation method and a liquid crystal display device.

Background

The liquid crystal display panel (Liquid Crystal Display, LCD) has advantages of low radiation, small volume, low energy consumption, etc., and is widely used in various electronic devices such as notebook computers, televisions, etc.

At present, the liquid crystal display panel utilizes an electric field formed by a common electrode and a pixel electrode to control liquid crystal molecules to deflect so as to achieve the purpose of displaying different gray-scale pictures.

However, when the liquid crystal display panel displays a picture, as a coupling capacitor exists between the common electrode and the data line, when the data voltage on the data line is suddenly changed, the voltages at two ends of the coupling capacitor are suddenly changed, so that the common voltage of the common electrode is fluctuated due to the capacitive coupling effect, and is difficult to keep stable, and further, the voltage difference between the common electrode and the pixel electrode is abnormal, so that deviation occurs between the deflection direction of liquid crystal molecules and the preset direction, and defects such as flicker (flicker), green light emission (greenish), crosstalk (cross talk) and the like of the display picture are caused, and the display effect and the yield of products are reduced. Thus, the common voltage needs to be compensated.

Disclosure of Invention

The embodiment of the application provides a common voltage compensation method and a liquid crystal display device, which are used for judging whether the number of positive and negative polarity sub-pixels is required to be determined by determining the driving mode and the type of a display picture, and determining a corresponding common voltage compensation value and compensating the data voltage of the positive and negative polarity sub-pixels, so that the compensated display picture can be normally displayed.

In order to achieve the above purpose, the present application adopts the following technical scheme:

in a first aspect, there is provided a common voltage compensation method applied to a liquid crystal display device including a liquid crystal display panel including a display area for displaying a display screen, the display area including a plurality of sub-pixels arranged in an array, the compensation method including: when the driving mode of the display picture is dot inversion, column 2 dot inversion or row 2 dot inversion, determining whether the display picture belongs to a first type of display picture; the first type of display picture comprises a full white display picture, a full black display picture and a three primary color display picture;

when the display picture does not belong to the first type of display picture, determining the number of first target sub-pixels and second target sub-pixels in each row of sub-pixels; the driving polarity corresponding to the first target sub-pixel is positive, and the driving polarity corresponding to the second target sub-pixel is negative;

and when the numbers of the first target sub-pixels and the second target sub-pixels are unequal for each row of sub-pixels, determining corresponding common voltage compensation values according to the data voltages of the first target sub-pixels and the data voltages of the second target sub-pixels and outputting the common voltage compensation values.

According to the public voltage compensation method provided by the first aspect, whether the number of the positive and negative polarity sub-pixels is required to be determined is judged by determining the driving mode of the display picture and the type of the display picture, and when the number of the positive and negative polarity sub-pixels is required to be determined and the number is different, the corresponding public voltage compensation value is determined and compensated by the data voltage of the positive and negative polarity sub-pixels, so that the compensated display picture can be normally displayed, and the purposes of solving the defects such as crosstalk among pixels and the like are achieved.

In a possible implementation manner of the first aspect, after determining that the display screen does not belong to the first type of display screen, before determining the number of the first target sub-pixel and the second target sub-pixel in each row of sub-pixels, the compensation method further includes:

determining the gray scale corresponding to each sub-pixel for each row of sub-pixels;

determining a sub-pixel of which the gray level meets a preset gray level range as a target sub-pixel, wherein the target sub-pixel comprises the first target sub-pixel and the second target sub-pixel.

In a possible implementation manner of the first aspect, determining and outputting a corresponding common voltage compensation value according to the data voltage respectively corresponding to the first target sub-pixel and the data voltage respectively corresponding to the second target sub-pixel includes:

determining an average value of data voltages of a plurality of first target sub-pixels as a first voltage for each row of sub-pixels;

determining an average value of the data voltages of the plurality of second target sub-pixels as a second voltage;

determining a voltage difference between the first voltage and the second voltage;

and determining the corresponding common voltage compensation value according to the voltage difference value and outputting the common voltage compensation value.

In a possible implementation manner of the first aspect, the compensation method further includes:

determining a driving mode of the display picture;

wherein the driving mode includes the dot inversion, the column 2 dot inversion, and the row 2 dot inversion.

In a second aspect, there is provided a liquid crystal display device comprising: a liquid crystal display panel, a timing controller and a compensation unit; the compensation unit is connected with the time sequence controller and the liquid crystal display panel; the liquid crystal display panel comprises a display area, wherein the display area is used for displaying a display picture, and the display area comprises a plurality of sub-pixels which are arranged in an array manner;

when the driving mode of the display picture is dot inversion, column 2 dot inversion or row 2 dot inversion, the time sequence controller is used for determining whether the display picture belongs to a first type of display picture; the first type of display picture comprises a full white display picture, a full black display picture and a three primary color display picture;

when the display picture does not belong to the first type of display picture, the time sequence controller is used for determining the number of first target sub-pixels and second target sub-pixels in each row of sub-pixels; the driving polarity corresponding to the first target sub-pixel is positive, and the driving polarity corresponding to the second target sub-pixel is negative;

for each row of sub-pixels, when the numbers of the first target sub-pixels and the second target sub-pixels are unequal, the time sequence controller is used for determining corresponding public voltage compensation values according to the data voltages of the first target sub-pixels and the data voltages of the second target sub-pixels and outputting the public voltage compensation values to the compensation unit;

the compensation unit is used for compensating the common voltage of the liquid crystal display panel according to the common voltage compensation value.

In a possible implementation manner of the second aspect, for each row of sub-pixels, the timing controller is configured to determine a gray level corresponding to each sub-pixel; and the sub-pixels are used for determining that the gray scale meets the preset gray scale range as target sub-pixels, and the target sub-pixels comprise the first target sub-pixels and the second target sub-pixels.

In a possible implementation manner of the second aspect, the timing controller is configured to determine, according to the data voltages respectively corresponding to the first target sub-pixel and the second target sub-pixel, a corresponding common voltage compensation value and output the common voltage compensation value to the compensation unit, where the determining includes:

the time schedule controller is used for determining that the average value of the data voltages of a plurality of first target sub-pixels is a first voltage;

the time schedule controller is used for determining that the average value of the data voltages of a plurality of the second target sub-pixels is a second voltage;

the timing controller is further configured to determine a voltage difference between the first voltage and the second voltage; and the compensation unit is used for determining the corresponding common voltage compensation value according to the voltage difference value and outputting the common voltage compensation value to the compensation unit.

In a possible implementation manner of the second aspect, the timing controller is configured to determine a driving manner of the display screen; wherein the driving mode includes the dot inversion, the column 2 dot inversion, and the row 2 dot inversion.

In a third aspect, a common voltage compensation device is provided for performing the common voltage compensation method as in the first aspect or any possible implementation of the first aspect above.

In a fourth aspect, a computer-readable storage medium is provided, in which a computer program or instructions is stored which, when read and executed by a computer, cause the computer to perform the common voltage compensation method as in the above first aspect or any possible implementation of the first aspect.

The embodiment of the application provides a common voltage compensation method and a liquid crystal display device, which judge whether the number of positive and negative polarity sub-pixels is required to be determined by determining the driving mode of a display picture and the type of the display picture, and when the number of the positive and negative polarity sub-pixels is required to be determined and the number is different, the corresponding common voltage compensation value is determined and compensated by the data voltage of the positive and negative polarity sub-pixels, so that the compensated display picture can be normally displayed, and the aim of solving the defects such as crosstalk among pixels is fulfilled.

Drawings

Fig. 1 is a schematic structural diagram of a liquid crystal display device according to an embodiment of the present disclosure;

FIG. 2 is a schematic diagram of the sub-pixel of FIG. 1;

FIG. 3 is a schematic waveform diagram corresponding to FIG. 2;

FIG. 4 is a schematic waveform diagram corresponding to a row of subpixels;

FIG. 5 is a schematic flow chart of a method for compensating a common voltage according to an embodiment of the present application;

FIG. 6 is a polarity diagram of a subpixel;

FIG. 7 is a flow chart of another method for compensating a common voltage according to an embodiment of the present disclosure;

fig. 8 is a schematic structural diagram of another liquid crystal display device according to an embodiment of the present application.

Reference numerals:

1-a liquid crystal display device; 10-a liquid crystal display panel; 11-grid lines; 12-data lines; 13-subpixels; 14-a common electrode line; 20-a drive unit; 31-a display area; 32-peripheral region; 200-a power module; 210-gate driver; 220-timing controller; 230-a data driver; 240-a compensation unit; vcom—a common voltage; vdata-data voltage.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more apparent, the present application will be further described in detail with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the present application.

In the description of the embodiments of the present application, unless otherwise indicated, "/" means or, for example, a/B may represent a or B; "and/or" herein is merely an association relationship describing an association object, and means that three relationships may exist, for example, a and/or B may mean: a exists alone, A and B exist together, and B exists alone.

The terms "first" and "second" are used below for descriptive purposes only and are not to be construed as indicating or implying 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 such feature. In the description of the present embodiment, unless otherwise specified, the meaning of "plurality" is two or more.

The terms of orientation such as "left", "right", "upper" and "lower" are defined with respect to the orientation in which the display assembly is schematically positioned in the drawings, and it should be understood that these directional terms are relative concepts that are used for descriptive and clarity with respect thereto and that may be varied accordingly in response to changes in the orientation in which the display device is positioned.

With the development of display technology, liquid crystal display technology has been widely used in various electronic devices. An electronic apparatus that performs display using a liquid crystal display technology includes a liquid crystal display device. The embodiment of the application provides a compensation method of a common electrode, which is applied to a liquid crystal display device in electronic equipment.

The electronic device may be a smart phone, a tablet computer, an electronic reader, a vehicle-mounted computer, a navigator, a digital camera, an intelligent television, an intelligent wearable device, and other electronic devices of different types. The embodiment of the present application does not impose any limitation on this.

Fig. 1 is a schematic diagram showing a structure of a liquid crystal display device in an exemplary technology. As shown in fig. 1, the liquid crystal display device generally includes a liquid crystal display panel 10 and a driving unit 20.

Wherein the driving unit 20 includes: the power module 200, the gate driver 210, the timing controller 220, and the data driver 230.

As shown in fig. 1, the liquid crystal display panel 10 includes a display area 31 and a peripheral area 32, and fig. 1 is a schematic view of the peripheral area 32 surrounding the display area 31. The display area 31 is for displaying an image, and the peripheral area 32 is for wiring.

As shown in fig. 1, in the display area 10, a plurality of gate lines 11 extending in a first direction (for example, a row direction), a plurality of data lines 12 extending in a second direction (for example, a column direction), and sub-pixels 13 arranged in an array defined by the gate lines 11 and the data lines 12 are distributed on the liquid crystal display panel 10, and the sub-pixels 13 include thin film transistors (thin film transistor, TFTs), storage capacitors, liquid crystal capacitors, and the like. The liquid crystal display panel 10 further has a plurality of common electrode lines 14 parallel to the gate lines 11, and the common electrode lines 14 are in one-to-one correspondence with the gate lines 11.

The timing controller 220 is connected to the gate driver 210 and the data driver 230, the gate driver 210 is connected to the plurality of gate lines 11, the data driver 230 is connected to the plurality of data lines 12, and the power module 200 is connected to the common electrode line 14.

It should be appreciated that in operation, the timing controller 220 is configured to provide control signals to the gate driver 210 and the data driver 230, control the gate driver 210 to provide a scan voltage to the sub-pixels 13 via the gate lines 11, and control the data driver 230 to provide a data voltage to the sub-pixels 13 via the data lines 12. The power supply module 200 supplies a common voltage Vcom to the sub-pixel 13 through the common electrode line 14.

Fig. 2 is a schematic diagram illustrating a structure of one sub-pixel 13 in fig. 1, and fig. 3 is a waveform diagram corresponding to fig. 2. As shown in fig. 2 and 3, in each sub-pixel 13, the gate electrode of the thin film transistor is connected to the gate line 11, and the gate line 11 has an input scanning voltage; the source electrode of the thin film transistor is connected with the data line 12, and the data line 12 is provided with an input data voltage Vdata; the first poles of the storage capacitor and the liquid crystal capacitor are connected with the drain electrode of the thin film transistor, and the second poles of the storage capacitor and the liquid crystal capacitor are connected with the common electrode line 14 and connected with the common voltage Vcom.

Based on this structure, when the thin film transistor is turned on during display of a picture, there is a coupling capacitance (i.e., a liquid crystal capacitance and a storage capacitance) between the common electrode line 14 and the data line 12, and when the data voltage Vdata on the data line 12 is suddenly changed, the voltages across the coupling capacitance are suddenly changed.

For example, as shown in fig. 3, when the data voltage Vdata suddenly changes upward (e.g., from 0V to 3V), the common voltage Vcom on the common electrode line 14 fluctuates upward due to the capacitive coupling effect; and when the data voltage Vdata suddenly changes downward (e.g., from 3V to 0V), the common voltage Vcom on the common electrode line 14 fluctuates downward due to the capacitive coupling effect.

Therefore, when the data voltage Vdata on the data line 12 is suddenly changed, the common voltage Vcom on the common electrode line 14 is difficult to keep stable, and further, the voltage difference between the common electrode and the pixel electrode is abnormal, so that deviation occurs between the deflection direction of the liquid crystal molecules and the preset direction, so that defects such as flickering, green light emitting, crosstalk and the like occur on the display screen, and the display effect and the yield of products are reduced.

Based on this, as shown in fig. 4, when the data voltages Vdata on the data lines 12 corresponding to the plurality of sub-pixels 13 connected to the same common electrode line 14 are suddenly changed, the common voltage Vcom on the common electrode line 14 is commonly affected by the plurality of data voltages Vdata, resulting in a drift.

For example, as shown in (b) of fig. 4, the data voltage Vdata1 corresponding to the 1 st sub-pixel 13 varies upward (e.g., from 3V to 5V), and the common voltage Vcom on the common electrode line 14 fluctuates upward (e.g., into a waveform corresponding to Vcom1 shown in the region P); while the data voltage Vdata2 corresponding to the 2 nd sub-pixel 13 changes downward (e.g., from 3V to 2V), the common voltage Vcom on the common electrode line 14 fluctuates downward (e.g., into a waveform corresponding to Vcom2 shown in the region P), but since the common electrode line 14 is simultaneously affected by two fluctuations, and since the influence of the upward fluctuation is large, the common voltage Vcom on the common electrode line 14 shifts upward after the influence of the two fluctuations, that is, the common voltage Vcom rises. On this basis, if the common voltage Vcom on the common electrode line 14 is affected by a plurality of fluctuations corresponding to the same row of sub-pixels 13, a large drift will occur, and thus compensation for the common voltage Vcom is required.

In view of this, the embodiment of the application provides a common voltage compensation method, which determines whether the number of the positive and negative polarity sub-pixels needs to be determined by determining the driving mode of the display picture and the type of the display picture, and when the number of the positive and negative polarity sub-pixels needs to be determined and the number is different, determines the corresponding common voltage compensation value by the data voltage of the positive and negative polarity sub-pixels and compensates the common voltage compensation value, so that the compensated display picture can be normally displayed, and the purposes of solving the defects such as crosstalk among pixels and the like are achieved.

The following describes a common voltage compensation method provided in the embodiments of the present application. The common voltage compensation method provided by the embodiment of the application is applied to a liquid crystal display device comprising a liquid crystal display panel, wherein the liquid crystal display panel comprises a display area, the display area is used for displaying a display picture, and the display area comprises a plurality of sub-pixels which are arranged in an array. Fig. 5 shows a flow chart of a method for compensating a common voltage according to an embodiment of the present application.

As shown in fig. 5, the method for compensating the common voltage according to the embodiment of the present application includes the following steps S100 to S300, which are described in detail below.

S100, when the driving mode of the display picture is dot inversion, column 2 dot inversion or row 2 dot inversion, determining whether the display picture is a first type display picture.

The first type of display screen comprises a full white display screen, a full black display screen and a three primary color display screen.

It should be understood that in order to prevent physical properties of liquid crystal from being damaged, for example, polarization of liquid crystal occurs when a fixed screen is displayed for a long time, the pixel electrode is generally driven with alternating current, that is, the data voltage Vdata supplied from the data line is an alternating current voltage.

For example, assuming that the common voltage Vcom is 7V and the data voltages Vdata are 13.5V and 0.5V, the voltages of 13.5V and 7V are equal to the voltages of 0.5V and 7V, so that when two sets of voltages are applied to both sides of the liquid crystal, the liquid crystal can deflect by the same angle, so that the liquid crystal display device 1 achieves the same display brightness. In general, the data voltage Vdata larger than the common voltage Vcom is referred to as a positive polarity voltage, and the driving polarity corresponding to the sub-pixel 13 to which the positive polarity voltage is applied is referred to as a positive polarity; the data voltage Vdata smaller than the common voltage Vcom is referred to as a negative polarity voltage, and the driving polarity corresponding to the sub-pixel 13 to which the negative polarity voltage is applied is referred to as a negative polarity.

Based on this, in the display process, the polarities of the sub-pixels 13 corresponding to the same pixel are opposite between the consecutive two frames of the display screen.

Although the liquid crystal can be prevented from being polarized by the ac drive, flicker of the display screen is easily caused by the ac drive. For flicker problems, spatial fusion is generally used to eliminate the flicker problem. The space fusion method refers to: the adjacent sub-pixels 13 are held at opposite drive polarities so that the optical response waveforms of the adjacent sub-pixels 13 are 180 deg. out of phase. In this way, the waveforms of adjacent sub-pixels 13 are spatially fused, and the flicker component present in each particular sub-pixel 13 is not discerned by the human eye.

A large number of driving modes with opposite polarities of adjacent sub-pixels 13 can be realized, mainly dot inversion, column 2 dot inversion and row 2 dot inversion. Fig. 6 shows a polarity diagram of one of the sub-pixels 13.

It should be understood that, as shown in fig. 6 (a), dot inversion refers to that each dot (sub-pixel) maintains opposite polarities from its neighboring four dots (sub-pixels) on the top, bottom, left, and right under the same frame display screen.

As shown in fig. 6 b, the column 2 dot inversion refers to the inversion of positive and negative polarities in units of 2 dots (two sub-pixels) on each column and the inversion of positive and negative polarities in units of columns on two adjacent columns of sub-pixels in the same frame display.

As shown in fig. 6 (c), the line 2 dot inversion refers to the inversion of positive and negative polarities in units of 2 dots (two sub-pixels) on each line, and the inversion of positive and negative polarities in units of lines on two adjacent lines under the same frame display screen.

When the display screen is driven in the dot inversion, the column 2 dot inversion, or the row 2 dot inversion, the data voltage Vdata corresponding to the same row of the sub-pixels 13 may have an upward or downward ripple influence on the common electrode, but in this case, a plurality of ripples may be in a ripple neutral condition.

It should be understood that the full white display screen is a screen corresponding to the maximum difference between the data voltage Vdata and the common voltage Vcom, and the full black display screen is a screen corresponding to the same difference between the data voltage Vdata and the common voltage Vcom (in this case, it may be considered that there is no positive or negative polarity); the three primary color display screens are referred to as a red display screen, a green display screen, and a blue display screen, and at this time, only the sub-pixels 13 of the corresponding color are applied with the data voltage Vdata different from the common voltage Vcom regardless of the display screens of the three primary colors.

In this way, in any driving method, when the first type of display screen is displayed, the number of sub-pixels 13 corresponding to positive polarity is substantially the same as the number of sub-pixels 13 corresponding to negative polarity in each row of sub-pixels 13, and the data voltage Vdata applied to the sub-pixels 13 corresponding to positive and negative polarities is equal to the common voltage Vcom, so that the influence of the data voltage Vdata corresponding to the plurality of sub-pixels 13 on the common voltage Vcom can be considered to be neutralized. In this case, it is considered that the common voltage Vcom is not influenced, and compensation is not necessary, but the influence on the common voltage Vcom is relatively remarkable in the other display screen, and compensation is necessary.

S200, when the display picture does not belong to the first type of display picture, determining the number of first target sub-pixels and second target sub-pixels in each row of sub-pixels 13; the driving polarity corresponding to the first target sub-pixel is positive, and the driving polarity corresponding to the second target sub-pixel is negative.

It should be understood that when the display screen does not belong to the first type of display screen, the influence of the plurality of data voltages Vdata corresponding to the same row of sub-pixels 13 on the common voltage Vcom is different, and if the number of the two sub-pixels 13 with the positive polarity and the negative polarity are equal, the applied voltages are different, but the number of times of rising fluctuation and falling fluctuation is the same, so that the drift caused by the same number of times of rising fluctuation and falling fluctuation is small, which is negligible.

S300, when the numbers of the first target sub-pixels and the second target sub-pixels are unequal for each row of sub-pixels 13, corresponding common voltage compensation values are determined and output according to the data voltages of the first target sub-pixels and the data voltages of the second target sub-pixels.

If the numbers of the two sub-pixels 13 with positive polarity and negative polarity are not equal, that is, the number of the first target sub-pixels is greater than the number of the second target sub-pixels, the common voltage Vcom will be caused to drift upward, and if the number of the first target sub-pixels is smaller than the number of the second target sub-pixels, the common voltage Vcom will be caused to drift downward, so that the common voltage Vcom needs to be compensated.

It will be appreciated that a corresponding common voltage compensation value may be determined from the data voltages of the first plurality of target sub-pixels and the data voltages of the second plurality of target sub-pixels in each row of sub-pixels 13. That is, each row of the sub-pixels 13 (each common electrode line 14) corresponds to one common voltage compensation value.

The embodiment of the application provides a public voltage compensation method, which judges whether the number of the positive and negative polarity sub-pixels is required to be determined by determining the driving mode of a display picture and the type of the display picture, and when the number of the positive and negative polarity sub-pixels is required to be determined and the number is different, the corresponding public voltage compensation value is determined and compensated by the data voltage of the positive and negative polarity sub-pixels, so that the compensated display picture can be normally displayed, and the aim of solving the defects such as crosstalk among pixels is fulfilled.

Optionally, as a possible implementation manner, the compensation method further includes: determining a driving mode of a display picture; the driving mode comprises dot inversion, column 2 dot inversion and row 2 dot inversion.

It will be appreciated that the manner in which the display is driven is determined, i.e. whether the drive polarities of the adjacent two rows of sub-pixels 13 and the adjacent two columns of sub-pixels 13 in the display are opposite. If the driving polarities of the two adjacent rows and the two adjacent columns of sub-pixels 13 are opposite, the dot inversion driving mode is adopted; if the driving polarities of two adjacent rows of sub-pixels 13 are opposite, but the polarities of the two columns of sub-pixels 13 are opposite, the row 2 point inversion is performed; if the driving polarities of the two adjacent columns of sub-pixels 13 are opposite, but the polarities of the two rows of sub-pixels 13 are opposite, the column 2 is inverted.

Optionally, as a possible implementation manner, after determining that the display screen does not belong to the first type of display screen, before determining the number of the first target sub-pixel and the second target sub-pixel in each row of sub-pixels 13, the compensation method further includes:

for each row of sub-pixels 13, the gray scale corresponding to each sub-pixel 13 is determined.

The sub-pixel 13 with the gray level meeting the preset gray level range is determined as a target sub-pixel, and the target sub-pixel comprises a first target sub-pixel and a second target sub-pixel.

It should be understood that if the input image display data is binary 8 bits, 8 gray levels from darkest to brightest of 2 are generated, that is, 256 different gray levels (for example, referred to as 0 th to 255 th gray levels) are generated. The intensity of the brightness of the liquid crystal display device 1 is determined by the voltage difference applied to both sides of the liquid crystal during display. The voltage at one side of the liquid crystal is fixed, namely the common voltage Vcom, the voltage at the other side is the data voltage, and 256 levels of different gray levels correspond to 256 levels of data voltage Vdata.

It should be understood that, taking VA liquid crystal as an example, the larger the voltage difference between the data voltage Vdata and the common voltage Vcom, the brighter the data voltage Vdata is displayed in the 256-level data voltage Vdata. Thus, it is assumed that the difference between the data voltage Vdata corresponding to the 0 th gray level and the common voltage Vcom is the smallest, and thus, the brightness corresponds to darkest; the data voltage Vdata corresponding to the 255 th gray level has the largest difference from the common voltage Vcom, and thus the brightness corresponds to the brightest. Since the data voltage Vdata driving the sub-pixel 13 is divided into the positive and negative voltages, each gray level corresponds to two data voltages Vdata of positive and negative polarities. For example, the common voltage is 6V, the positive polarity data voltage corresponding to the 255 th gray level is 11V, and the negative polarity data voltage is 1V.

It should be appreciated that the magnitude of the data voltage Vdata is not linearly dependent on the setting of the gray scale levels, but non-linearly dependent, since the human eye is less sensitive to variations in luminance that are too bright and more sensitive to variations in luminance that are darker. Then, the influence on the sub-pixels 13 with lower gray scale levels is more serious and the influence on the sub-pixels 13 with higher gray scale levels is less when the data voltages Vdata corresponding to the plurality of sub-pixels 13 are converted, thereby paying more attention to the sub-pixels 13 with lower gray scale levels when the common voltage Vcom is compensated.

It should be understood that the preset gray scale range may be set and modified as needed, and this embodiment of the present application does not impose any limitation, and for example, the preset gray scale range may be set to [30,200]. That is, after determining that the display screen does not belong to the first type of display screen, it is determined, for each row of sub-pixels 13, whether the gray scale corresponding to each sub-pixel 13 belongs to the preset gray scale range, when the gray scale belongs to the 30 th to 200 th gray scales, the sub-pixel 13 is used as the target sub-pixel, if the corresponding driving polarity is positive, the first target sub-pixel is used, and if the corresponding driving polarity is negative, the second target sub-pixel is used.

Optionally, as a possible implementation manner, fig. 7 shows a schematic flow chart of another common voltage compensation method provided in an embodiment of the present application, as shown in fig. 7, S300 includes:

s310, determining, for each row of sub-pixels 13, an average value of the data voltages of the plurality of first target sub-pixels as the first voltage.

S320, determining an average value of the data voltages of the plurality of second target sub-pixels as a second voltage.

It should be understood that the data voltage of the first target sub-pixel will affect the upward fluctuation of the common voltage Vcom, the average value of the data voltage of the first target sub-pixel is the voltage value that may be reached after the upward drift of the common voltage Vcom, that is, the first voltage, and the data voltage of the second target sub-pixel will affect the downward fluctuation of the common voltage Vcom, and the average value of the data voltage of the second target sub-pixel is the voltage value that may be reached after the downward drift of the common voltage Vcom, that is, the second voltage.

S330, determining a voltage difference value between the first voltage and the second voltage.

S340, according to the voltage difference value, a corresponding common voltage Vcom compensation value is determined and output.

It should be understood that determining the voltage difference between the first voltage and the second voltage is the fluctuation influence of the common voltage Vcom after neutralization, and thus, from the voltage difference, a corresponding common voltage compensation value can be determined. By compensating the common voltage Vcom, the image quality of the picture can be improved, and the product competitiveness can be improved.

Fig. 8 shows a schematic structural diagram of a liquid crystal display device 1 according to an embodiment of the present application. As shown in fig. 8, the liquid crystal display device 1 includes: the liquid crystal display panel 10, the timing controller 220, and the compensation unit 240.

The compensation unit 240 is connected to both the timing controller 220 and the liquid crystal display panel 10.

The timing controller 220 and the compensation unit 240 are connected through an ICC bus.

The liquid crystal display panel 10 includes a display area 31 for displaying a display screen, and a peripheral area 32 for wiring, and the display area 31 includes a plurality of sub-pixels arranged in an array, as shown in fig. 8. As shown in fig. 8, assuming that the horizontal direction x is the row direction, the sub-pixels arranged along the horizontal direction x are one row of sub-pixels. The vertical direction y is a column direction, and the subpixels arranged along the vertical direction y are a column of subpixels. Of course, the row and column directions may be interchanged, which is not subject to any limitation by the embodiments of the present application.

When the driving mode of the display frame is dot inversion, column 2 dot inversion or row 2 dot inversion, the timing controller 220 is configured to determine whether the display frame belongs to the first type of display frame; the first type of display screen comprises a full white display screen, a full black display screen and a three primary color display screen.

When the driving mode of the display picture is not dot inversion, column 2 dot inversion or row 2 dot inversion, no compensation is performed. When the display screen belongs to the first type of display screen, compensation of the common voltage Vcom is not performed either.

When the display screen does not belong to the first type of display screen, the timing controller 220 is configured to determine the number of the first target sub-pixels and the second target sub-pixels in each row of sub-pixels 13; the driving polarity corresponding to the first target sub-pixel is positive, and the driving polarity corresponding to the second target sub-pixel is negative.

When the number of the first target sub-pixels and the second target sub-pixels is equal for each row of the sub-pixels 13, the influence on the common voltage Vcom can be considered to be almost equal, and thus compensation may be omitted.

For each row of sub-pixels, when the numbers of the first target sub-pixels and the second target sub-pixels are unequal, the timing controller 220 is configured to determine a corresponding common voltage compensation value according to the data voltages of the plurality of first target sub-pixels and the data voltages of the plurality of second target sub-pixels and output the common voltage compensation value to the compensation unit 240.

The compensation unit 240 is used for compensating the common voltage of the liquid crystal display panel 10 according to the common voltage compensation value.

As shown in fig. 8, the liquid crystal display device 1 further includes a power supply module 200, a gate driver 210, and a data driver 230 as shown in fig. 1. The connection relationship between the power module 200, the gate driver 210 and the data driver 230 and the liquid crystal display panel 10 is described above, and is not described here again.

It should be understood that, after the timing controller 220 determines the common voltage compensation value, the common voltage compensation value may be updated to the compensation unit 240 through the ICC bus, and the compensation unit 240 may further provide the voltage to the corresponding common electrode line 14 on the lcd panel 10 for compensation according to the common voltage compensation value.

It should be understood that here, the compensation unit 240 and the power module 200 may be integrated on one chip, and the compensation unit 240 directly outputs the compensated common voltage.

The embodiment of the application provides a liquid crystal display device, which judges whether the number of the positive and negative polarity sub-pixels is required to be determined by determining the driving mode of a display picture and the type of the display picture, and when the number of the positive and negative polarity sub-pixels is required to be determined and the number is different, the corresponding common voltage compensation value is determined and compensated by the data voltage of the positive and negative polarity sub-pixels, so that the compensated display picture can be normally displayed, and the aim of solving the defects such as crosstalk among pixels is fulfilled.

Alternatively, as a possible implementation manner, the timing controller 220 is configured to determine a driving manner of the display screen; the driving mode comprises dot inversion, column 2 dot inversion and row 2 dot inversion.

It should be understood that there is typically, in addition to this, row inversion and column inversion, which is not compensated for by the present application.

Alternatively, as a possible implementation manner, for each row of sub-pixels, the timing controller 220 is configured to determine a gray level corresponding to each sub-pixel 13; the sub-pixel 13, which is further used for determining that the gray level satisfies the preset gray level range, is a target sub-pixel, and the target sub-pixel includes a first target sub-pixel and a second target sub-pixel.

The preset gray scale range can be set and modified as required, and the embodiment of the application does not limit the preset gray scale range.

Alternatively, as a possible implementation manner, the timing controller 220 is configured to determine a corresponding common voltage compensation value according to the data voltage respectively corresponding to the first target sub-pixel and the data voltage respectively corresponding to the second target sub-pixel, and output the common voltage compensation value to the compensation unit 240, where the determining includes:

the timing controller 220 is configured to determine an average value of the data voltages of the plurality of first target sub-pixels as a first voltage; the timing controller 220 is configured to determine an average value of the data voltages of the plurality of second target sub-pixels as a second voltage; the timing controller 220 is further configured to determine a voltage difference between the first voltage and the second voltage; and for determining a corresponding common voltage compensation value according to the voltage difference and outputting it to the compensation unit 240.

The embodiment of the application also provides a common voltage compensation device which is used for executing the common voltage compensation method.

The beneficial effects of the public voltage compensation device provided in the embodiment of the application are the same as those of the public voltage compensation method, and are not described herein.

Embodiments of the present application also provide a computer-readable storage medium having a computer program or instructions stored therein, which when read and executed by a computer, cause the computer to perform the common voltage compensation method.

The beneficial effects of the computer readable storage medium provided in the embodiment of the present application are the same as those of the common voltage compensation method described above, and are not described herein again.

The above embodiments are only for illustrating the technical solution of the present application, and are not limiting; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art 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 and scope of the technical solutions of the embodiments of the present application, and are intended to be included in the scope of the present application.

Claims

1. A common voltage compensation method, which is applied to a liquid crystal display device including a liquid crystal display panel, the liquid crystal display panel including a display area for displaying a display screen, the display area including a plurality of sub-pixels arranged in an array, the compensation method comprising:

when the driving mode of the display picture is dot inversion, column 2 dot inversion or row 2 dot inversion, determining whether the display picture belongs to a first type of display picture; the first type of display picture comprises a full white display picture, a full black display picture and a three primary color display picture;

for each row of sub-pixels, when the numbers of the first target sub-pixels and the second target sub-pixels are unequal, determining corresponding common voltage compensation values according to the data voltages of the first target sub-pixels and the data voltages of the second target sub-pixels, and outputting the common voltage compensation values;

determining and outputting a corresponding common voltage compensation value according to the data voltages respectively corresponding to the first target sub-pixel and the second target sub-pixel, including:

for each row of sub-pixels, determining an average value of the data voltages of a plurality of first target sub-pixels as a first voltage, wherein the average value is a voltage value reached after the common voltage is increased;

determining an average value of the data voltages of the plurality of second target sub-pixels as a second voltage, wherein the average value is a voltage value reached after the common voltage is reduced;

determining and outputting the corresponding common voltage compensation value according to the voltage difference value;

the compensation method further comprises the following steps:

determining a driving mode of the display picture, wherein the driving mode comprises the dot inversion, the column 2 dot inversion and the row 2 dot inversion;

wherein the pixel electrode is driven with an alternating current.

2. The compensation method according to claim 1, wherein after determining that the display screen does not belong to the first type of display screen, before determining the number of first target sub-pixels and second target sub-pixels in each row of sub-pixels, the compensation method further comprises:

3. A liquid crystal display device, comprising: a liquid crystal display panel, a timing controller and a compensation unit; the compensation unit is connected with the time sequence controller and the liquid crystal display panel; the liquid crystal display panel comprises a display area, wherein the display area is used for displaying a display picture, and the display area comprises a plurality of sub-pixels which are arranged in an array manner;

the compensation unit is used for compensating the common voltage of the liquid crystal display panel according to the common voltage compensation value;

the time schedule controller is configured to determine a corresponding common voltage compensation value according to the data voltages respectively corresponding to the first target sub-pixel and the second target sub-pixel, and output the common voltage compensation value to the compensation unit, and includes:

the time sequence controller is used for determining that the average value of the data voltages of the plurality of first target sub-pixels is a first voltage, and the average value is a voltage value reached after the common voltage is increased;

the time sequence controller is used for determining that the average value of the data voltages of the plurality of second target sub-pixels is a second voltage, and the average value is a voltage value reached after the common voltage is reduced;

the timing controller is further configured to determine a voltage difference between the first voltage and the second voltage; the common voltage compensation unit is used for determining a corresponding common voltage compensation value according to the voltage difference value and outputting the common voltage compensation value to the compensation unit;

the time schedule controller is used for determining a driving mode of the display picture; the driving mode includes the dot inversion, the column 2 dot inversion, and the row 2 dot inversion; wherein the pixel electrode is driven with an alternating current.

4. A liquid crystal display device according to claim 3, wherein the timing controller is configured to determine, for each row of sub-pixels, a corresponding gray level for each sub-pixel; and the sub-pixels are used for determining that the gray scale meets the preset gray scale range as target sub-pixels, and the target sub-pixels comprise the first target sub-pixels and the second target sub-pixels.

5. A common voltage compensation device for performing the common voltage compensation method according to claim 1 or 2.

6. A computer-readable storage medium, in which a computer program or instructions is stored which, when read and executed by a computer, cause the computer to perform the common voltage compensation method according to claim 1 or 2.