WO2020172922A1

WO2020172922A1 - Charging method and device for monochromatic picture of tri-gate panel

Info

Publication number: WO2020172922A1
Application number: PCT/CN2019/078604
Authority: WO
Inventors: 杨惠; 何涛; 吴宇
Original assignee: 深圳市华星光电半导体显示技术有限公司
Priority date: 2019-02-28
Filing date: 2019-03-19
Publication date: 2020-09-03
Also published as: CN109658901A; CN109658901B

Abstract

A charging method and device for a monochromatic picture of a tri-gate panel, the charging method for the monochromatic picture of the tri-gate panel comprising: step 10, acquiring grey scale data of a monochromatic picture of a tri-gate panel; step 20, detecting a high grey scale value H and a low grey scale value 0 in the grey scale data of the monochromatic picture, and determining an output time sequence by which a source chip outputs the high grey scale value H and the low grey scale value 0; step 30, when the monochromatic picture is displayed and the low grey scale value 0 is outputted before the high grey scale value H, the source chip replacing the low grey scale value 0 with a preset charging value for output, and then replacing the high grey scale value H with an overvoltage compensation value for output; and a corresponding charging device for the monochromatic picture of the tri-gate panel is provided. The charging method and device for the monochromatic picture of the tri-gate panel reduce the grey scale voltage difference of the monochromatic picture, and increase the rise time of pixel voltage, thereby solving the problem of the inadequate charging capacity of monochromatic pictures of tri-gate panels.

Description

Charging method and device for monochromatic picture of tri-grid panel

Technical field

The present invention relates to the field of display technology, and in particular to a method and device for charging a monochromatic screen of a tri-gate panel.

Background technique

TFT (Thin Film Transistor) LCD, or thin film field effect transistor LCD, is one of the active matrix type liquid crystal displays (AM-LCD). Liquid crystal display, especially TFT-LCD, is currently the only display device that can fully catch up with and exceed CRT in terms of comprehensive performance such as brightness, contrast, power consumption, life, volume and weight. It has excellent performance, good mass production characteristics, and automation. High degree, low cost of raw materials, broad development space, will quickly become mainstream products in the new century, and a bright spot for global economic growth in the 21st century.

Today's panel market is becoming saturated and market prices are constantly falling. In order to make profits, it is imperative to improve and innovate to reduce costs. In order to reduce the number of source driver ICs (IC) and reduce costs, people have proposed a panel tri-gate architecture, that is, the number of gate scan lines is tripled, and the source The number of driver chips has been reduced to 1/3 of the original, greatly reducing costs.

For ultra-high definition (UD) tri-gate panels, the three sub-pixels of BGR are arranged vertically, the scanning frequency is three times that of normal panels, and the charging time for each row is one-third of that of normal panels, which is likely to cause charging insufficient.

When the existing source line overvoltage compensation (OD) technology changes from the previous scan line to the current scan line, and the grayscale data changes between low grayscale and high grayscale, first precharge higher/lower The gray-scale voltage is then charged into the normal gray-scale voltage, so that the dots on the current scan line can be charged and discharged faster.

Refer to Figure 1, which is a schematic diagram of the grayscale data of a monochrome screen to illustrate the grayscale data of a monochrome screen. Screen 1 is a red (R) screen with a grayscale of 255, and screen 2 is a green ( G) Picture, Picture 3 is a blue (B) picture with a gray scale of 64. For a monochrome screen, when the grayscale data changes in the order of grayscale 0→H, the source line overvoltage compensation increases the voltage difference between low grayscale value 0→high grayscale value H, and the pixel voltage rise time will become longer. long. For example, when the overvoltage compensation technology is used in the prior art, if the high grayscale value H is 127 grayscale, the corresponding overvoltage compensation value can be 200 grayscale. If the high grayscale value H is 180 grayscale, the The voltage compensation value can be 255 gray scales. For high gray scale values H greater than 180 gray scales, the overvoltage compensation value can be 255 gray scales. Then there is a risk that the voltage greater than 180 gray scales cannot be filled in time.

Refer to Figure 2, which is a schematic diagram of the effect of the existing source line overvoltage compensation technology. In the figure, G127 represents a monochrome image with a green gray scale of 127, the gray scale value H of the green sub-pixel is 127, and the adjacent red sub-pixels and blue The gray scale value of the color sub-pixel is 0. When the overvoltage compensation technology is used, the corresponding overvoltage compensation value is 200 gray scales. The length of the OD is used to represent the pressure difference between the overvoltage compensation value and the high grayscale value H.

Summary of the invention

Therefore, the object of the present invention is to provide a method and device for charging a monochromatic image of a tri-gate panel to solve the problem of insufficient charging capability of the monochromatic image of the tri-gate panel.

To achieve the above objective, the present invention provides a method for charging a monochromatic screen of a tri-gate panel, which includes:

Step 10. Obtain grayscale data of a monochrome image of the tri-gate panel;

Step 20: Detect the high grayscale value H and the low grayscale value 0 in the grayscale data of the monochrome image, and determine the output timing of each high grayscale value H and low grayscale value 0 of the source chip;

Step 30. When the monochrome image is displayed, when the low grayscale value 0 before the high grayscale value H is output, the source chip uses the precharge value to replace the low grayscale value 0 for output, and then replaces the high grayscale with the overvoltage compensation value The order value H is output.

Among them, the pre-charged value satisfies:

Where n is a natural number, and m1, m2, m(n-2), ... m(n-1) increase and less than 255.

The pre-charge value is 1 or 2 or 3.

Among them, the pre-charged value satisfies:

The present invention also provides a charging device for a monochromatic screen of the tri-gate panel, which includes:

An obtaining module for obtaining grayscale data of a monochrome picture of the tri-gate panel;

The detection module is used to detect the high grayscale value H and the low grayscale value 0 in the grayscale data of the monochrome image, and determine the output timing of the source chip to output each high grayscale value H and low grayscale value 0 ；

The precharge module is used to control the source chip to use the precharge value to replace the low grayscale value 0 for output when the low grayscale value 0 before the high grayscale value H is output when the monochrome screen is displayed, and then the source chip Replace the high grayscale value H with an overvoltage compensation value for output.

Among them, the pre-charged value satisfies:

The pre-charge value is 1 or 2 or 3.

Among them, the pre-charged value satisfies:

In summary, the charging method and device for monochromatic screens of tri-gate panels of the present invention reduce the gray-scale voltage difference of monochromatic screens, increase the rise time of pixel voltage, and solve the problem of insufficient charging capacity of tri-gate panels for monochromatic screens.

Description of the drawings

The technical solutions and other beneficial effects of the present invention will be made obvious by describing the specific embodiments of the present invention in detail below in conjunction with the accompanying drawings.

In the attached picture,

Figure 1 is a schematic diagram of grayscale data of a monochrome picture;

Figure 2 is a schematic diagram of the effect of the existing source line overvoltage compensation technology;

Figure 3 is a schematic diagram of a voltage-gray scale curve;

Figure 4 is a schematic diagram of a voltage-transmittance curve;

5 is a schematic diagram of an effect of an embodiment of a method for charging a monochrome image of a tri-gate panel according to the present invention;

FIG. 6 is a flowchart of the charging method of the monochromatic picture of the tri-gate panel of the present invention.

detailed description

Figure 3 is a schematic diagram of a voltage-grayscale curve. The horizontal axis represents voltage and the vertical axis represents grayscale. It uses a vertical alignment (VA) panel in normally black mode as an example to draw a voltage-grayscale curve. It can be seen that the gamma voltage required when the gray level changes is higher when the gray level is low. As shown in Fig. 3, the voltage difference between gray scale 0 and gray scale 1 is about 200 millivolts. For other gray scales, the pressure difference required for gray scale changes is about tens of millivolts, for example, gray scale When the gray scale changes from 254 to 255, the pressure difference is about 50-60 mV.

FIG. 4 is a schematic diagram of the voltage-transmittance curve. From the voltage-transmittance curve shown in FIG. 4, it can be seen that the change of the gray scale has little effect on the transmittance of the panel when the gray scale is low.

According to FIG. 3 and FIG. 4, the present invention can solve the insufficient charging capacity of the monochromatic picture of the tri-gate panel, design a smaller overvoltage compensation value for each gray level, and make the pixels of each gray level voltage be filled in time.

Refer to FIG. 6, which is a flowchart of a charging method for a monochromatic picture of a tri-gate panel of the present invention. The present invention mainly includes:

Step 10. Obtain the grayscale data of a monochromatic picture of the tri-gate panel; for example, according to the arrangement order of the three sub-pixels of the BGR, the grayscale data of the monochromatic picture can be 0 H (0 H 0 or H 0 0) , Where the high grayscale value H corresponds to the color to be displayed.

Step 20: Detect the high grayscale value H and low grayscale value 0 in the grayscale data of the monochrome image, and determine the output timing of each high grayscale value H and low grayscale value 0 of the source chip; The grayscale data of the color screen detects the size of the high grayscale value H, that is, detects the grayscale value of a specific sub-pixel in the monochrome screen, and further determines the grayscale corresponding to each sub-pixel in the monochrome screen as shown in Figure 1. Value and output timing.

Step 30. When the monochrome image is displayed, when the low grayscale value 0 before the high grayscale value H is output, the source chip uses the precharge value to replace the low grayscale value 0 for output, and then replaces the high grayscale with the overvoltage compensation value The order value H is output. According to Fig. 3 and Fig. 4, because the gamma voltage required for gray scale changes at low gray scales is higher and the gray scales are larger, and the gray scale changes at low gray scales have little effect on the transmittance of the panel. The adjacent gray-scale value before the gray-scale value H is replaced with the pre-charged value of 0, and the pre-charged value is used to replace the low gray-scale value 0 for output to achieve pre-charge in advance, reducing the gray-scale pressure difference when displaying a monochrome screen , The pixel voltage rise time is increased, so that the pixel can obtain the gray-scale voltage corresponding to the high gray-scale value H with a smaller overvoltage compensation value.

Among them, the pre-charge Value and the high grayscale value H are natural numbers, and the selection range of the pre-charge Value can be determined according to the principles of FIG. 3 and FIG. 4. The formula of pre-charge Value can be set as:

Where n is a natural number, and m1, m2, m(n-2), ... m(n-1) increase and less than 255. For example, the BGR grayscale value of the front end, that is, the image data input, can be set to 1 1 1. At this time, the source driver chip can be set to output a pixel voltage with a grayscale value of 3 3. When displaying a monochrome screen, before the grayscale data changes from a low grayscale value of 0 to a high grayscale value H, you can replace the grayscale value 0 with a grayscale value of 1 or 2 or 3 to achieve pre-charge. At this time, pre-charge Value is 1 or 2 or 3, so that a high grayscale value H can be obtained with a smaller overvoltage compensation value. At this time, according to the aforementioned pre-charge Value formula, n=3, and m1 and m2 can be further set to 40 and 100, respectively. At this time, the pre-charge Value formula can be set as:

Refer to FIG. 5, which is a schematic diagram of an effect of an embodiment of a method for charging a monochrome image of a tri-gate panel of the present invention. In the figure, G127 represents a monochrome picture with a green gray scale of 127, and the gray scale value H of the green sub-pixel is 127. According to the present invention, the gray scale value of the adjacent blue sub-pixel is precharged from 0 to 3 to realize precharge. Therefore, the corresponding overvoltage compensation value can be reduced to 160 gray scales. The length of OD in FIG. 5 is used to represent the pressure difference between the overvoltage compensation value and the high gray scale value H. By pre-charging the grayscale value of the adjacent blue sub-pixels from 0 to 3, the grayscale voltage difference of the monochrome image is reduced, the pixel voltage rise time is increased, and the charging capability of the monochrome image is improved.

Furthermore, according to the method for charging a monochromatic screen of a tri-gate panel of the present invention, the invention also provides a charging device for a monochromatic screen of a tri-gate panel, which mainly includes:

As mentioned above, for those of ordinary skill in the art, various other corresponding changes and modifications can be made according to the technical solutions and technical ideas of the present invention, and all these changes and modifications shall belong to the appended claims of the present invention. The scope of protection.

Claims

A charging method for a monochromatic picture of a tri-gate panel includes:

Step 10. Obtain grayscale data of a monochrome image of the tri-gate panel;

Step 20: Detect the high grayscale value H and the low grayscale value 0 in the grayscale data of the monochrome image, and determine the output timing of each high grayscale value H and low grayscale value 0 of the source chip;

Step 30. When the monochrome image is displayed, when the low grayscale value 0 before the high grayscale value H is output, the source chip uses the precharge value to replace the low grayscale value 0 for output, and then replaces the high grayscale with the overvoltage compensation value The order value H is output.
The method for charging a monochromatic picture of a tri-gate panel according to claim 1, wherein the pre-charge value Value satisfies:

Where n is a natural number, and m1, m2, m(n-2), ... m(n-1) increase and less than 255.
The method for charging a monochrome image of a tri-gate panel as claimed in claim 1, wherein the pre-charge value Value is 1 or 2 or 3.
The method for charging a monochromatic picture of a tri-gate panel according to claim 3, wherein the pre-charge value Value satisfies:
A charging device for a monochromatic image of a tri-grid panel, comprising:

An obtaining module for obtaining grayscale data of a monochrome picture of the tri-gate panel;

The detection module is used to detect the high grayscale value H and the low grayscale value 0 in the grayscale data of the monochrome image, and determine the output timing of the source chip to output each high grayscale value H and low grayscale value 0 ；

The precharge module is used to control the source chip to use the precharge value to replace the low grayscale value 0 for output when the low grayscale value 0 before the high grayscale value H is output when the monochrome screen is displayed, and then the source chip Replace the high grayscale value H with an overvoltage compensation value for output.
The charging device for a monochromatic screen of a tri-gate panel according to claim 5, wherein the precharge value Value satisfies:

Where n is a natural number, and m1, m2, m(n-2), ... m(n-1) increase and less than 255.
The charging device for a monochromatic screen of a tri-gate panel as claimed in claim 1, wherein the pre-charge value Value is 1 or 2 or 3.
8. The charging device for a monochromatic screen of a tri-gate panel according to claim 7, wherein the pre-charge value Value satisfies: