CN110599973B

CN110599973B - Driving method of display panel

Info

Publication number: CN110599973B
Application number: CN201910766588.4A
Authority: CN
Inventors: 璧典附; 赵丽
Original assignee: Shenzhen China Star Optoelectronics Technology Co Ltd
Current assignee: TCL Huaxing Photoelectric Technology Co Ltd
Priority date: 2019-08-20
Filing date: 2019-08-20
Publication date: 2020-11-10
Anticipated expiration: 2039-08-20
Also published as: CN110599973A; WO2021031268A1

Abstract

The present disclosure provides a driving method of a display panel, including: inputting a gate signal to a first pixel unit and a second pixel unit to turn on a first transistor of the first pixel unit and a second transistor of the second pixel unit; inputting a first data signal to the first pixel unit to charge the first pixel unit when the first transistor of the first pixel unit is turned on; and inputting a second data signal to the second pixel unit to charge the second pixel unit when the second transistor of the second pixel unit is turned on, wherein an integrated area of a waveform of the first data signal is larger than an integrated area of a waveform of the second data signal.

Description

Driving method of display panel

Technical Field

The present disclosure relates to the field of display devices, and more particularly, to a driving method of a display panel.

Background

The Vertical Alignment (VA) display mode is a common display mode for large-sized liquid crystal display devices because of its advantages such as high contrast and no rubbing alignment. The VA mode realizes different transmittances by causing different degrees of liquid crystal tilting, thereby displaying a picture. A spacer (PS) is disposed in a display region of the display panel and is mainly used for supporting the upper and lower substrates. In general, a spacer includes both a primary spacer and a secondary spacer. The main spacer functions to support the upper and lower substrates to maintain a space (cell gap) between the two substrates at a specific value. The secondary spacers are used for auxiliary support, and the height of the secondary spacers is lower than that of the main spacers. When the display panel is pressed, the secondary spacers play a supporting role.

The technology of integrating a color filter on array (COA) with a color filter is to fabricate a Color Filter (CF) on an array substrate. The film thickness of the blue color resist is generally higher than the red and green color resists depending on the material characteristics. In order to ensure that the step difference between the primary and secondary spacers is maintained at a predetermined value, the primary spacers are disposed in the pixels corresponding to the blue color resists, and the secondary spacers are disposed in the pixels corresponding to the red and green color resists. Further, in order to increase the aperture ratio, spacers are formed at corresponding positions of Thin Film Transistors (TFTs).

The main spacer is always in a compressed state after the cell is formed, i.e., the main spacer continuously applies pressure to the TFT. Referring to fig. 1, a graph of voltage versus current for a TFT of a display panel in the related art is shown. A curve 11 represents a voltage-to-current graph of the TFT on which the main spacer is disposed, and a curve 12 represents a voltage-to-current graph of the TFT on which the sub spacer is disposed. As can be seen from fig. 1, the pressure applied by the main spacers causes a significant variation in the electrical properties of the TFTs corresponding to the blue pixels, and further causes the display effect of the blue pixels to be different from that of the other color pixels, resulting in the degradation of the display panel.

In view of the above, it is desirable to provide a driving method of a display panel to solve the problems in the prior art.

Disclosure of Invention

In order to solve the above-mentioned problems of the prior art, an object of the present disclosure is to provide a driving method of a display panel, which reduces the electrical variation of the TFT of the pixel unit caused by the pressure applied by the main spacer by changing the data signal of the pixel unit where the main spacer is located, thereby avoiding the difference between the display effect of the pixel unit and other pixels.

To achieve the above object, the present disclosure provides a driving method of a display panel, the display panel including a first pixel unit for displaying a first color and a second pixel unit for displaying a second color, wherein the driving method includes: inputting a gate signal to the first pixel unit and the second pixel unit to turn on a first transistor of the first pixel unit and a second transistor of the second pixel unit; inputting a first data signal to the first pixel unit to charge the first pixel unit when the first transistor of the first pixel unit is turned on; and inputting a second data signal to the second pixel unit to charge the second pixel unit when the second transistor of the second pixel unit is turned on, wherein an integrated area of a waveform of the first data signal is larger than an integrated area of a waveform of the second data signal.

In one preferred embodiment of the present disclosure, the initial charging voltage value of the first data signal is greater than the initial charging voltage value of the second data signal.

In one preferred embodiment of the present disclosure, the ending charge voltage value of the first data signal is equal to the ending charge voltage value of the second data signal.

In one preferred embodiment of the present disclosure, the time for charging the first pixel unit when receiving the first data signal is longer than the time for charging the second pixel unit when receiving the second data signal.

In one preferred embodiment of the present disclosure, the on time of the first transistor of the first pixel unit is equal to the on time of the second transistor of the second pixel unit.

In one preferred embodiment of the present disclosure, the first pixel unit and the second pixel unit are connected to a first gate line, and the first pixel unit and the second pixel unit are respectively connected to a first data line and a second data line which are adjacent to each other, wherein in the step of inputting the gate signal to the first pixel unit and the second pixel unit, the driving method further includes: inputting the gate signal to the first gate line to sequentially turn on the first transistor of the first pixel unit and the second transistor of the second pixel unit.

In one preferred embodiment of the present disclosure, the display panel includes a first substrate, a second substrate disposed opposite to the first substrate, and a first spacer and a second spacer disposed between the first substrate and the second substrate, wherein one end of the first spacer is disposed on the first substrate and the other end is in contact with the second substrate, and one end of the second spacer is disposed on the first substrate and the other end is spaced apart from the second substrate by a distance.

In one preferred embodiment of the present disclosure, in a vertical direction, an orthogonal projection of the first spacer on the first substrate corresponds to the first transistor of the first pixel unit, and an orthogonal projection of the second spacer on the first substrate corresponds to the second transistor of the second pixel unit.

In one preferred embodiment of the present disclosure, the first substrate includes a pixel array layer and a color filter layer, the pixel array layer includes the first transistor and the second transistor, and the color filter layer is disposed on the pixel array layer, and corresponding ends of the first spacer and the second spacer are connected to the color filter layer.

In one preferred embodiment of the present disclosure, the color filter layer includes a blue color filter, a red color filter, and a green color filter, and the first pixel unit corresponds to the blue color filter, and the second pixel unit corresponds to the red color filter or the green color filter.

Compared with the prior art, the charging difference between the first pixel unit and other second pixel units is corrected by changing the first data signal input into the first pixel unit where the first spacer is located. Specifically, the integrated area of the waveform of the first data signal is made larger than the integrated area of the waveform of the second data signal by changing the charging voltage or the charging time of the first data signal. By the design, the first pixel electrode of the first pixel unit can be charged to the same potential as the second pixel electrode of the second pixel unit, the uniformity of the display panel is improved, and the display quality is improved.

Drawings

FIG. 1 is a graph showing voltage versus current curves of TFTs of a display panel according to the prior art;

FIG. 2 is a circuit diagram of a display device according to a first preferred embodiment of the present disclosure;

FIG. 3 is a cross-sectional view of the display panel of the display device of FIG. 2 along a line A-A;

FIG. 4 is a waveform diagram illustrating driving signals of a display panel of the display device of FIG. 2; and

fig. 5 shows waveforms of driving signals of a display panel according to a second preferred embodiment of the present disclosure.

Detailed Description

In order to make the aforementioned and other objects, features and advantages of the present disclosure comprehensible, preferred embodiments accompanied with figures are described in detail below.

Referring to fig. 2, a circuit diagram of a display device 1 according to a first preferred embodiment of the disclosure is shown. The display device 1 includes a display panel 100 and a driver 200. The display panel 100 is provided with a plurality of

pixel units

130, 140, a plurality of data lines 110, and a plurality of scan lines 120, wherein the plurality of

pixel units

130, 140 are defined by the plurality of data lines 110 and the plurality of scan lines 120 crossing each other. The driver 200 includes a timing controller 210, a source driver 220, and a gate driver 230. The timing controller 210 is connected to the source driver 220 and the gate driver 230, and the source driver 220 and the gate driver 230 are connected to the display panel 100.

Referring to fig. 3, a cross-sectional view of the display panel 100 of the display device 1 of fig. 2 along the a-a section line is shown. The display panel 100 includes a first substrate 101, a second substrate 102, a liquid crystal layer, a first spacer 103, and a second spacer 104. The first substrate 102 is disposed opposite to the second substrate 102. The liquid crystal layer is disposed between the first substrate 101 and the second substrate 102. The first and

second spacers

103 and 104 are also disposed between the first and

second substrates

101 and 102. The first substrate 102 is a color filter integrated thin film transistor array substrate, that is, the first substrate 102 includes a pixel array layer 1011 and a color filter layer 1012, wherein the color filter layer 1012 is disposed on the pixel array layer 1011, and the color filter layer 1012 includes a blue color resistor B, a red color resistor R, a green color resistor G, a white color resistor, and the like.

As shown in fig. 3, the pixel unit of the present disclosure is divided into a first pixel unit 130 and a second pixel unit 140, wherein the first pixel unit 130 is the pixel unit provided with the first spacer 103, and the second pixel unit 140 is the pixel unit provided with the second spacer 104. That is, the first spacer 103 is disposed in the first pixel unit 130, and the second spacer 104 is disposed in the second pixel unit 140. One end of the first spacer 103 is disposed on the color filter layer 1012 of the first substrate 101 and the other end is in contact with the second substrate 102. One end of the second spacer 104 is disposed on the first substrate 101 and the other end is spaced apart from the second substrate 102 by a distance 106. The first spacers 103 serve to support the first and

second substrates

101 and 102 to maintain a space (cell gap)105 of the first and

second substrates

101 and 102 at a specific value. The second spacers 104 serve as auxiliary supports, and the height H2 of the second spacers 104 is lower than the height H1 of the first spacers 103. When the display panel 100 is pressed, it is supported by the second spacer 104.

As shown in fig. 3, the film thickness of the blue color resist B is generally higher than the red color resist R and the green color resist G according to the material characteristics of the color filter layer 1012. In order to ensure that the spacing 105 between the first substrate 101 and the second substrate 102 is maintained at a specific value, the first spacers 103 are usually disposed in the pixel units where the blue color resists B are located. That is, the first pixel unit 130 is a pixel unit corresponding to the blue color resistance B, and the second pixel unit 140 is a pixel unit corresponding to the color resistance other than the blue color resistance B. In the first preferred embodiment, the second pixel unit 140 corresponding to the red color resistor R is taken as an example, but not limited thereto. In other embodiments, the second pixel unit 140 can also be configured to correspond to a green color resistance G, a white color resistance, or a yellow color resistance.

As shown in fig. 2, the first pixel unit 130 further includes a first transistor 131 and a first pixel electrode 132, and the second pixel unit 140 further includes a second transistor 141 and a second pixel electrode 142. The first transistor 131 and the second pixel unit 140 of the first pixel unit 130 are connected to the first gate line 1201, and the first pixel unit 130 and the second pixel unit 140 are connected to the adjacent first data line 1101 and second data line 1102, respectively.

As shown in fig. 3, in the vertical direction, the orthographic projection of the first spacer 103 on the first substrate 101 corresponds to the first transistor 131 of the first pixel unit 130, and the orthographic projection of the second spacer 104 on the first substrate 101 corresponds to the second transistor 141 of the second pixel unit 140. By this design, the aperture ratio of the display panel 100 can be effectively increased.

The present disclosure provides a driving method of a display panel 100, which reduces an electrical variation of a first transistor 131 of a first pixel unit 130 caused by a pressure applied by a first spacer 103 by changing a waveform of a data signal 310 of the first pixel unit 130 where the first spacer 103 is located, thereby preventing a display effect of the first pixel unit 130 from being different from that of a second pixel unit 140. The driving method of the display panel 100 of the present disclosure specifically includes the following steps.

First, the timing controller 210 generates a scan control signal and a data control signal by the received timing synchronization signal. The timing controller 210 provides a scan control signal to the gate driver 230 so that the gate driver 230 generates the gate signal 400. And, the gate driver 230 transmits the gate signal 400 to the corresponding gate line 120 of the display panel 100 through the plurality of scan lines 120. Specifically, the gate driver 230 sequentially inputs the gate signal 400 to the first pixel unit 130 and the second pixel unit 140 through the first gate line 1201 to turn on the first transistor 131 of the first pixel unit 130 and the second transistor 141 of the second pixel unit 140.

Next, the source driver 220 receives a data control signal with respect to each pixel unit supplied from the timing controller 210. The source driver 220 converts the gray signal of each pixel cell into a data signal according to the data control signal, and supplies the data signal to each pixel cell through the corresponding data line 110. Specifically, when the first transistor 131 of the first pixel unit 130 is turned on, the source driver 220 inputs the first data signal 310 to the first pixel unit 130 through the first data line 1101 to charge the first pixel electrode 132 of the first pixel unit 130, so that the first pixel unit 130 emits blue light. Then, when the second transistor 141 of the second pixel unit 140 is turned on, the source driver 220 inputs a second data signal 320 to the second pixel unit 140 through the second data line 1102 to charge the second pixel electrode 142 of the second pixel unit 140, so that the second pixel unit 140 emits red light.

Referring to fig. 4, it shows a waveform diagram of the driving signals of the display panel 100 of the display device 1 of fig. 2, wherein the horizontal axis represents time and the vertical axis represents voltage values, and the waveforms of the data signals and the gate signals output by the source driver 220 and the gate driver 230 are approximate to square waves. The driving signals of the display panel 100 include gate signals and data signals, wherein fig. 4 shows the corresponding timing relationship between the gate signals 400 and the first data signals 310 and the second data signals 320. As shown in fig. 3, since the first spacer 103 is compressed after being formed into the box, the first spacer 103 exerts a pressure on the first transistor 131, so that the electrical property of the first transistor 131 corresponding to the first pixel unit 130 is significantly changed. In order to avoid the above problem, the present disclosure corrects the charging difference between the first pixel unit 130 and other pixel units by changing the first data signal 310 input to the first pixel unit 130 where the first spacer 103 is located.

As shown in fig. 4, in the case of corresponding to the same waveform of the gate signal 400 (i.e., the on time of the first transistor 131 of the first pixel unit 130 is equal to the on time of the second transistor 141 of the second pixel unit 140), the charging time lengths of the first data signal 310 and the second data signal 320 are the same, but the charging voltages of the first data signal 310 and the second data signal 320 are different. Specifically, the initial charging voltage value V2 of the first data signal 310 is greater than the initial charging voltage value V1 of the second data signal 320. Also, the end charging voltage value V1 of the first data signal 310 is equal to the end charging voltage value V1 of the second data signal 320. Accordingly, the integrated area of the waveform of the first data signal 310 is larger than the integrated area of the waveform of the second data signal 320. In the first preferred embodiment, the potential of the first data signal 310 written into the first pixel unit 130 corresponding to the first spacer 103 is higher than the potential of the data signals written into other pixel units, so that the abnormal first pixel unit 130 can be charged with a higher potential within a fixed charging time, and the first pixel electrode 132 can be charged to the same potential as the second pixel electrode 142 of the second pixel unit 140, thereby improving the uniformity of the display panel 100 and further improving the display quality.

Referring to fig. 5, a waveform diagram of a driving signal of a display panel according to a second preferred embodiment of the present disclosure is shown, wherein a horizontal axis represents time and a vertical axis represents voltage values. The display panel of the second preferred embodiment is similar to the display panel 100 of the first preferred embodiment, and is not described herein again. The driving signal of the second preferred embodiment contains a gate signal output by the gate driver and a data signal output by the source driver, and the waveforms of the output data signal and the gate signal approximate a square wave. Fig. 5 shows the corresponding timing relationship between the gate signal 500 and the first data signal 610 and the second data signal 620, wherein the gate signal 500 is a plurality of signals continuously output from the same gate line, and the first data signal 610 and the second data signal 620 are respectively output from two adjacent data lines. Two adjacent data lines are respectively connected with the adjacent first pixel unit and the second pixel unit. In the second preferred embodiment, the first data signal 610 is input to a first pixel cell where a first spacer is correspondingly disposed, and the second data signal 620 is input to a second pixel cell where a second spacer is correspondingly disposed. The first spacer applies a pressure to the first transistor of the first pixel unit to cause a significant variation in the electrical property of the first transistor. In order to avoid the above problem, the present disclosure corrects the charging difference between the first pixel unit and other pixel units by changing the first data signal 610 inputted to the first pixel unit where the first spacer is located.

As shown in fig. 5, in the case of corresponding to the same waveform of the gate signal 500 (i.e., the on time of the first transistor of the first pixel unit is equal to the on time of the second transistor of the second pixel unit), the charging voltages of the first data signal 610 and the second data signal 620 are the same, but the lengths of the charging times of the first data signal 610 and the second data signal 620 are different. Specifically, the charging voltage value V1 of the first data signal 610 is equal to the charging voltage value V1 of the second data signal 620, and the charging time of the first data signal 610 is greater than the charging time of the second data signal 620. That is, the interval time of T2 to T3 is greater than the interval time of T5 to T6. Accordingly, the integrated area of the waveform of the first data signal 610 is larger than the integrated area of the waveform of the second data signal 620. In the second preferred embodiment, the time for charging the first pixel unit receiving the first data signal 610 is longer than the time for charging the second pixel unit receiving the second data signal 620, so that the first pixel electrode of the first pixel unit is charged to the same potential as the second pixel electrode of the second pixel unit, the uniformity of the display panel is improved, and the display quality is further improved.

In summary, the present disclosure corrects the charging difference between the first pixel unit and the other second pixel units by changing the first data signal inputted to the first pixel unit where the first spacer is located. Specifically, the integrated area of the waveform of the first data signal is made larger than the integrated area of the waveform of the second data signal by changing the charging voltage or the charging time of the first data signal. By the design, the first pixel electrode of the first pixel unit can be charged to the same potential as the second pixel electrode of the second pixel unit, the uniformity of the display panel is improved, and the display quality is improved.

The foregoing is merely a preferred embodiment of the present disclosure, and it should be noted that modifications and refinements may be made by those skilled in the art without departing from the principle of the present disclosure, and these modifications and refinements should also be regarded as the protection scope of the present disclosure.

Claims

1. A driving method of a display panel, the display panel comprising a first pixel unit for displaying a first color, a second pixel unit for displaying a second color, a first substrate, a second substrate disposed opposite to the first substrate, and a first spacer and a second spacer disposed between the first substrate and the second substrate, wherein one end of the first spacer is disposed on the first substrate and the other end is in contact with the second substrate, one end of the second spacer is disposed on the first substrate and the other end is spaced apart from the second substrate by a distance, and in a vertical direction, an orthogonal projection of the first spacer on the first substrate corresponds to a first transistor of the first pixel unit, and an orthogonal projection of the second spacer on the first substrate corresponds to a second transistor of the second pixel unit, wherein the driving method comprises:

inputting a gate signal to the first pixel unit and the second pixel unit to turn on the first transistor of the first pixel unit and the second transistor of the second pixel unit;

inputting a first data signal to the first pixel unit disposed corresponding to the first spacer to charge the first pixel unit when the first transistor of the first pixel unit is turned on; and

when the second transistor of the second pixel unit is turned on, inputting a second data signal to the second pixel unit disposed corresponding to the second spacer to charge the second pixel unit, wherein an integrated area of a waveform of the first data signal is larger than an integrated area of a waveform of the second data signal.

2. The method of driving a display panel according to claim 1, wherein a start charge voltage value of the first data signal is larger than a start charge voltage value of the second data signal.

3. The method of driving a display panel according to claim 2, wherein the end-of-charge voltage value of the first data signal is equal to the end-of-charge voltage value of the second data signal.

4. The method of driving a display panel according to claim 1, wherein a time for which the first pixel unit receives the first data signal to be charged is longer than a time for which the second pixel unit receives the second data signal to be charged.

5. The method of driving a display panel according to claim 1, wherein an on time of the first transistor of the first pixel unit is equal to an on time of the second transistor of the second pixel unit.

6. The method of driving a display panel according to claim 1, wherein the first pixel unit and the second pixel unit are connected to a first gate line, and the first pixel unit and the second pixel unit are connected to adjacent first data line and second data line, respectively, wherein in the step of inputting the gate signal to the first pixel unit and the second pixel unit, the method further comprises: inputting the gate signal to the first gate line to sequentially turn on the first transistor of the first pixel unit and the second transistor of the second pixel unit.

7. The method for driving a display panel according to claim 1, wherein the first substrate includes a pixel array layer and a color filter layer, the pixel array layer includes the first transistor and the second transistor, and the color filter layer is provided over the pixel array layer, and corresponding ends of the first spacer and the second spacer are connected to the color filter layer.

8. The method as claimed in claim 7, wherein the color filter layer comprises a blue color filter, a red color filter, and a green color filter, and the first pixel unit corresponds to the blue color filter and the second pixel unit corresponds to the red color filter or the green color filter.