Display panel and discharge control method for display panel

Abstract

This application provides a display panel and a discharge control method for the display panel. The display panel includes: a scan driving circuit; a discharge terminal and a switching circuit, wherein the switching circuit is connected to the discharge terminal and a data line; wherein the scan driving circuit is used to output a scan signal to the scan line during the power-off period of the display panel, causing the corresponding pixel unit to turn on; the switching circuit is used to turn on during the power-off period and connect the data line and the discharge terminal when turned on, so that the residual charge in the turned-on pixel unit is released to the discharge terminal through the corresponding data line. This display panel solves the problem in the prior art that residual charge still exists in the pixel units of the display panel after power-off.

Description

Technical Field

[0001] This application relates to the field of display panel technology, and more particularly to a display panel and a discharge control method for the display panel. Background Technology

[0002] Thin-film transistors (TFTs) are the core of modern display technology. Each pixel unit in a display panel is equipped with an independent TFT, which acts as a switch to control the charging of the capacitor in the pixel unit. Early TFTs used amorphous silicon (A-Si) as the semiconductor material. With the increasing demand for large-size display panels, TFTs using high-mobility oxide (HMO) as the semiconductor material have become increasingly common in the pixel units of display panels. Compared with A-Si TFTs, HMO TFTs have a higher carrier mobility, enabling faster charging of the pixel unit's capacitor. However, HMO TFTs also have lower leakage current, causing the charge stored in the pixel unit's capacitor to remain for a longer period. This results in residual charge remaining in the pixel units after the display panel is turned off, causing image retention and degrading the display quality. Summary of the Invention

[0003] This application provides a display panel and a discharge control method for the display panel to solve the problem in the prior art that the pixel units of the display panel still have residual charge after the power is turned off.

[0004] In a first aspect, this application provides a display panel, the display panel further comprising: a scan driving circuit; a discharge terminal and a switching circuit, the switching circuit being connected to the discharge terminal and connected to a data line; wherein, the scan driving circuit is used to output a scan signal to the scan line during the power-off period of the display panel to turn on the corresponding pixel unit, the switching circuit being used to turn on during the power-off period, and connecting the data line and the discharge terminal when turned on, so that the residual charge in the turned-on pixel unit is released to the discharge terminal through the corresponding data line.

[0005] Optionally, the switching circuit includes: a first power supply terminal; a plurality of discharge control modules, wherein the first terminal of each discharge control module is connected to the discharge terminal, the discharge control module corresponds one-to-one with the data line, the second terminal of each discharge control module is connected to the corresponding data line, and the controlled terminal of each discharge control module is connected to the first power supply terminal. The first power supply terminal is used to pull down the potential of the controlled terminal of the discharge control module during the power-off period so that the potential of the controlled terminal of the discharge control module is less than the turn-on threshold potential. The discharge control module is used to connect the corresponding data line to the discharge terminal when the potential of the controlled terminal is less than the turn-on threshold potential.

[0006] Optionally, the discharge terminal is a ground terminal or a second power supply terminal, wherein the second power supply terminal is used to connect to a constant negative voltage.

[0007] Optionally, the scan driving circuit includes: P cascaded scan driving units, each scan driving unit being connected to a corresponding row of scan lines, where P is a positive integer, and each scan driving unit being used to output the scan signal to the corresponding scan line during the power-off period.

[0008] Optionally, the nth-level scan drive unit includes: an output module, a clock signal terminal, a third power supply terminal, and a reset signal terminal. The first terminal of the output module is connected to the clock signal terminal, and the second terminal of the output module is connected to the nth scan line, where n is a positive integer less than P. The nth-level scan drive unit further includes: an energy storage module, the first terminal of which is connected to the third power supply terminal; and a charging reset module, the first terminal of which is connected to the second terminal of the energy storage module, and the second terminal of which is connected to the controlled terminal of the output module, with the connection node being a pull-up node. The controlled terminal of the charging reset module is connected to the reset signal terminal. The third power supply terminal is used to raise the potential of the second terminal of the energy storage module during the power-off period, so that the potential of the second terminal of the energy storage module is higher than the potential of the pull-up node. The reset signal terminal is used to raise the potential of the controlled terminal of the charging reset module during the power-off period. The charging reset module is used to turn on when the potential of the controlled terminal is raised, and raise the potential of the pull-up node when the potential of the second terminal of the energy storage module is raised and is higher than the potential of the pull-up node. The clock signal terminal is used to raise the potential of the first terminal of the output module during the power-off period. The output module is used to output the scan signal to the nth scan line when the potential of the pull-up node is raised.

[0009] Optionally, the nth-level scanning drive unit further includes: a charging module and a fourth power supply terminal, wherein a first terminal of the charging module is connected to the fourth power supply terminal, the fourth power supply terminal is used to raise the potential of the first terminal of the charging module, and a second terminal of the charging module is connected to the pull-up node; the nth-level scanning drive unit further includes: a charging sustaining module, wherein a first terminal of the charging sustaining module is connected to the second terminal of the energy storage module, and a second terminal of the charging sustaining module is connected to the pull-up node; The charging module is used to raise the potential of the pull-up node during the pre-charge scan period, and the charging maintenance module is used to raise the potential of the second terminal of the energy storage module when the potential of the pull-up node is raised and is higher than the potential of the second terminal of the energy storage module.

[0010] Optionally, the nth level scanning drive unit further includes: a first reset module, a first end of the first reset module being connected to the third power supply terminal, a second end of the first reset module being connected to the pull-up node, the third power supply terminal being used to reset the potential of the first end of the first reset module during a blank period, the first reset module being used to reset the potential of the pull-up node during the blank period, and the charging sustaining module being used to maintain the potential of the second end of the energy storage module when the potential of the pull-up node is reset.

[0011] Optionally, the nth-level scanning drive unit further includes: a second reset module, the first end of the second reset module being connected to a third power supply terminal, the second end of the second reset module being connected to the pull-up node, and the controlled end of the second reset module being connected to a start signal terminal or a cascade signal terminal of the (n-1)th-level scanning drive unit; wherein, the third power supply terminal is used to reset the potential of the first end of the second reset module during the frame header reset period of the display panel, the start signal terminal or the cascade signal terminal of the (n-1)th-level scanning drive unit is used to raise the potential of the controlled end of the second reset module during the frame header reset period, the second reset module is used to reset the potential of the pull-up node when the potential of the controlled end is raised, the reset signal terminal is used to raise the potential of the controlled end of the charging reset module during the frame header reset period to enable the charging reset module, and the charging reset module resets the potential of the second end of the energy storage module when the pull-up node is reset.

[0012] Secondly, this application provides a discharge control method for a display panel, the method being applied to any of the aforementioned display panels, the method comprising: detecting whether the display panel has entered the power-off period; when the display panel enters the power-off period, controlling the switching circuit to turn on to connect the data line and the discharge terminal, so that the residual charge in the activated pixel unit is released to the discharge terminal through the corresponding data line.

[0013] Optionally, the switching circuit includes: a first power supply terminal and multiple discharge control modules. Controlling the switching circuit to turn on includes: outputting a preset potential signal to the first power supply terminal to turn on each discharge control module, such that when the discharge control module is turned on, the corresponding data line is connected to the discharge terminal, and the preset potential signal is less than the turn-on threshold potential of the discharge control module.

[0014] In this embodiment, during the power-off period of the display panel, the scanning drive circuit outputs a scanning signal to each scan line, which turns on the corresponding pixel unit and the switching circuit. When the switch is turned on, the data line is connected to the discharge terminal, so that the residual charge in the turned-on pixel unit is released to the discharge terminal through the corresponding data line. This solves the problem that the pixel unit still has residual charge after the display panel is turned off in the prior art, avoids the situation of image retention after the display panel is turned off, and improves the display quality of the product. Attached Figure Description The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0015] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] One or more embodiments are illustrated by way of example with reference numerals in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0017] Figure 1 This is a schematic diagram of the structure of a first type of display panel provided in an embodiment of this application; Figure 2 This is a schematic diagram of the structure of a second type of display panel provided in an embodiment of this application; Figure 3 A timing diagram of the signals of the reset signal terminal, the third power supply terminal, the clock signal terminal in the prior art, and the first power supply terminal provided in the embodiments of this application; Figure 4 This is a schematic diagram of the structure of a scanning driving unit provided in an embodiment of this application; Figure 5(a) is a schematic diagram of signal transmission of the shutdown period scanning drive unit provided in an embodiment of this application; Figure 5(b) is a schematic diagram of signal transmission of the precharge period scanning drive unit provided in an embodiment of this application; Figure 5(c) is a schematic diagram of signal transmission of the scanning drive unit during the scanning period provided in an embodiment of this application; Figure 5(d) is a schematic diagram of signal transmission of the blank time period scanning drive unit provided in the embodiment of this application; Figure 5(e) is a schematic diagram of signal transmission of the frame header reset period scanning drive unit provided in an embodiment of this application; The accompanying diagrams in the instruction manual are illustrated below: 10. Pixel unit; 20. Scan driving circuit; 21. Scan driving unit; 210. Output module; 211. First energy storage module; 212. Second energy storage module; 213. Charging reset module; 214. Charging module; 215. Charging maintenance module; 216. First reset module; 217. Second reset module; 218. Cascade module; 30. Switching circuit; 31. Discharge control module. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0019] The following disclosure provides numerous different embodiments or examples for implementing various structures of the invention. To simplify the disclosure, specific examples of components and arrangements are described below. These are merely examples and are not intended to limit the scope of the invention. Furthermore, reference numerals and / or letters may be repeated in different examples. Such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed.

[0020] To address the technical problem in the prior art where residual charge remains in pixel units of display panels after power-off, this application provides a display panel and a discharge control method for the display panel. This method solves the problem of residual charge remaining in pixel units of display panels after power-off, avoids image retention after power-off, and improves product display quality.

[0021] Figure 1A display panel provided in this application embodiment includes: a plurality of pixel units 10 arranged in a matrix, a plurality of rows of scan lines, and a plurality of columns of data lines. Each row of the scan lines is connected to a corresponding row of pixel units 10 among the plurality of pixel units 10, and each column of the data lines is connected to a corresponding column of pixel units 10 among the plurality of pixel units 10. The display panel further includes: Scan drive circuit 20; The discharge terminal DIS and the switching circuit 30 are connected to the discharge terminal DIS and the data line. The scanning drive circuit 20 is used to output a scanning signal to the scanning line during the power-off period of the display panel, so that the corresponding pixel unit 10 is turned on. The switching circuit 30 is used to connect the data line and the discharge terminal DIS during the power-off period, so that the residual charge in the turned-on pixel unit 10 is released to the discharge terminal DIS through the corresponding data line.

[0022] For example, Figure 1 as well as Figure 2 In the table, G1, G2...GP represent the 1st scan line, the 2nd scan line...the Pth scan line, respectively, and L1, L2...LM represent the 1st data line, the 2nd data line...the Mth data line, respectively, where P and M are both positive integers.

[0023] For example, such as Figure 2 As shown, the pixel unit 10 includes a first thin-film transistor T0 and a first capacitor C0. The scan driving circuit 20 is used to output a scan signal to each scan line during the power-off period of the display panel, so that the first thin-film transistor T0 in the corresponding pixel unit 10 is turned on. The switching circuit 30 is used to connect the data line and the discharge terminal DIS during the power-off period, so that the residual charge in the first capacitor C0 in the turned-on pixel unit 10 is released to the discharge terminal DIS through the corresponding data line.

[0024] Through the above embodiments, during the power-off period of the display panel, the scanning drive circuit 20 outputs a scanning signal to each scan line, which turns on the corresponding pixel unit 10. When the switching circuit 30 is turned on, it connects the data line and the discharge terminal DIS, so that the residual charge in the turned-on pixel unit 10 is released to the discharge terminal DIS through the corresponding data line. This solves the problem that the pixel unit still has residual charge after the display panel is turned off in the prior art, avoids the situation of image retention after the display panel is turned off, and improves the display quality of the product.

[0025] In one alternative embodiment, such as Figure 2 As shown, the switching circuit 30 includes: First power supply terminal SW; Multiple discharge control modules 31 are provided. The first end of each discharge control module 31 is connected to the discharge terminal DIS. Each discharge control module 31 corresponds to a data line. The second end of each discharge control module 31 is connected to the corresponding data line. The controlled end of each discharge control module 31 is connected to the first power supply terminal SW. The first power supply terminal SW is used to lower the potential of the controlled end of the discharge control module 31 during the power-off period so that the potential of the controlled end of the discharge control module 31 is less than the turn-on threshold potential. When the potential of the controlled end is less than the turn-on threshold potential, the discharge control module 31 is used to connect the corresponding data line to the discharge terminal DIS.

[0026] For example, such as Figure 2 As shown, each discharge control module 31 includes: a second thin-film transistor T2, which is a P-type thin-film transistor (P-TFT). The controlled terminal of the discharge control module 31 is the gate of the second thin-film transistor T2, the first terminal of the discharge control module 31 is the source of the second thin-film transistor T2, and the second terminal of the discharge control module 31 is the drain of the second thin-film transistor T2. When the potential of the gate of the second thin-film transistor T2 is less than the aforementioned turn-on threshold potential (the aforementioned turn-on threshold potential is a negative potential), the second thin-film transistor T2 is turned on, that is, the discharge control module 31 is turned on. For example, as shown... Figure 3 As shown, "Display" indicates the transition period from the display panel's display time to its power-off time, and "Power off" indicates the display panel's power-off time. Figure 3 As shown, during the power-off period of the display panel, the potential of the first power terminal SW is pulled low. After the display panel enters the power-off period, the potential of the first power terminal SW is always lower than the power-on threshold potential.

[0027] In one optional embodiment, the discharge terminal is either a ground terminal or a second power supply terminal, wherein the second power supply terminal is used to connect to a constant negative voltage.

[0028] For example, such as Figure 2 As shown, each discharge control module 31 includes: a second thin-film transistor T2, the second thin-film transistor T2 is a P-type thin-film transistor, the controlled terminal of the discharge control module 31 is the gate of the second thin-film transistor T2, the first terminal of the discharge control module 31 is the source of the second thin-film transistor T2, and the second terminal of the discharge control module 31 is the drain of the second thin-film transistor T2. Based on the turn-on conditions of the P-type thin-film transistor (the potential of the gate is less than the turn-on potential threshold and the potential of the gate is less than the potential of the source), when the discharge terminal DIS is the second power supply terminal, the constant negative voltage connected to the second power supply terminal should be greater than the potential of the first power supply terminal SW when the display panel is in the power-off period.

[0029] In one alternative embodiment, such as Figure 2 As shown, the scan driving circuit 20 includes P cascaded scan driving units 21, each scan driving unit 21 being connected to a corresponding row of scan lines, where P is a positive integer, and each scan driving unit 21 being used to output the scan signal to the corresponding scan line during the power-off period.

[0030] For example, the operating cycle of the display panel includes a display period and a power-off period. The display period consists of multiple consecutive driving periods (each driving period displays one frame of the image). Each driving period includes a frame header reset period, a precharge period, a scan period, and a blank period. The blank period is the time between the end time of the scan period of the current frame and the start time of the frame header reset period of the next frame. It should be noted that the blank period of the last driving period refers to the time between the end time of the scan period of the current frame and the start time of the power-off period.

[0031] In one alternative embodiment, such as Figure 4 As shown, the nth-level scan driving unit 21 includes: an output module 210, a clock signal terminal CK, a third power supply terminal VSS, and a reset signal terminal CLR. The first terminal of the output module 210 is connected to the clock signal terminal CK, and the second terminal of the output module 210 is connected to the nth scan line, where n is a positive integer less than P. The nth-level scan driving unit 21 also includes: Energy storage module, wherein the first end of the energy storage module is connected to the third power supply terminal VSS; The charging reset module 213 has its first end connected to the second end of the energy storage module, and its second end connected to the controlled end of the output module 210, with the connection node being a pull-up node PU. The controlled end of the charging reset module 213 is also connected to the reset signal terminal CLR. Specifically, the third power supply terminal VSS is used to raise the potential of the second terminal of the energy storage module during the power-off period, so that the potential of the second terminal of the energy storage module is higher than the potential of the pull-up node PU. The reset signal terminal CLR is used to raise the potential of the controlled terminal of the charging reset module 213 during the power-off period. The charging reset module 213 is used to turn on when the potential of the controlled terminal is raised, and raise the potential of the pull-up node PU when the potential of the second terminal of the energy storage module is higher than the potential of the pull-up node PU. The clock signal terminal CK is used to raise the potential of the first terminal of the output module 210 during the power-off period. The output module 210 is used to output the scan signal to the nth scan line Gn when the potential of the pull-up node PU is raised.

[0032] For example, the above-mentioned energy storage module is defined as the first energy storage module, such as... Figure 4 As shown, the first end of the first energy storage module 211 is connected to the third power supply terminal VSS, and the first end of the charging reset module 213 is connected to the second end of the first energy storage module 211. The nth level scanning drive unit 21 further includes a second energy storage module 212, the first end of which is connected to the pull-up node PU, and the second end of which is connected to the nth scan line Gn. For example, the first energy storage module 211 includes a first capacitor Cboost, the second energy storage module 212 includes a second capacitor Cbt, the charging reset module 213 includes a third thin-film transistor T1, and the output module 210 includes a fourth thin-film transistor M10. The third thin-film transistor T1 and the fourth thin-film transistor M10 are both N-type thin-film transistors. The output module 210 is activated when the potential of the controlled terminal rises. The controlled terminal of the charging reset module 213 is the gate of the third thin film transistor T1, the first terminal of the charging reset module 213 is the source of the third thin film transistor T1, and the second terminal of the charging reset module 213 is the drain of the third thin film transistor T1. The controlled terminal of the output module 210 is the gate of the fourth thin film transistor M10, the first terminal of the output module 210 is the source of the fourth thin film transistor M10, and the second terminal of the output module 210 is the drain of the fourth thin film transistor M10.

[0033] For example, such as Figure 3 As shown, Display represents the blank period during the last frame driving time of the display panel, and Power off represents the power-off period of the display panel. Figure 3 As shown, in the prior art, when the display panel enters the power-off period, the potential of the reset signal terminal CLR, the potential of the third power supply terminal VSS, and the potential of the clock signal terminal CK are all first pulled high and then gradually decreased. Utilizing this characteristic, such as... Figure 3As shown in Figure 5(a), Figure 5(a) is a schematic diagram of the potential signal flow of the nth level scan drive unit during the power-off period of the display panel. In Figure 5(a), the solid line represents signal transmission and is a high-potential signal transmission, and the dashed line represents no signal transmission. During the power-off period of the display panel, the third power supply terminal VSS raises the potential of the second terminal of the first energy storage module 211, making the potential of the second terminal of the first energy storage module 211 higher than the potential of the pull-up node PU. The reset signal terminal CLR raises the potential of the controlled terminal of the charging reset module 213 during the power-off period. The charging reset module 213 is used to turn on when the potential of the controlled terminal rises, and when it is turned on and the first When the potential of the second terminal of the energy storage module 211 is higher than the potential of the pull-up node PU, the potential of the pull-up node PU is raised (actually, the first energy storage module 211 discharges to charge the second energy storage module 212 to raise the pull-up node PU). The clock signal terminal CK raises the potential of the first terminal of the output module 210 during the power-off period. The output module 210 is used to turn on when the potential of the pull-up node PU is raised, and outputs the scanning signal to the nth scan line Gn when it is turned on and the potential of the first terminal is raised. This realizes that the nth level scan drive unit outputs the scanning signal to the nth scan line Gn during the power-off period, so that the nth row pixel unit is turned on.

[0034] For example, such as Figure 4 As shown in Figure 5(a), the nth-level scanning drive unit 21 further includes a cascade module 218. The controlled terminal of the cascade module 218 is connected to the pull-up node PU. The first terminal of the cascade module 218 is connected to the clock signal terminal CK. The second terminal of the cascade module 218 serves as the cascade signal terminal of the nth-level scanning drive unit 21 (the cascade signal terminal of the nth-level scanning drive unit is used to represent Tn). As shown in Figure 5(a), when the display panel enters the power-off period, the cascade module 218 is turned on due to the potential rise of the pull-up node PU. At this time, the second terminal of the cascade module 218 outputs the cascade signal. The cascade module 218 includes an eighth thin-film transistor M11. The eighth thin-film transistor M11 is an N-type thin-film transistor and is turned on when the potential of the controlled terminal rises. The controlled terminal of the cascade module 218 is the gate of the eighth thin-film transistor M11. The first terminal of the cascade module 218 is the source of the eighth thin-film transistor M11. The second terminal of the cascade module 218 is the drain of the eighth thin-film transistor M11.

[0035] In one alternative embodiment, such as Figure 4As shown, the nth-level scanning drive unit 21 further includes: a charging module 214 and a fourth power supply terminal VGH. The first end of the charging module 214 is connected to the fourth power supply terminal VGH, which is used to raise the potential of the first end of the charging module 214. The second end of the charging module 214 is connected to the pull-up node PU. The nth-level scanning drive unit 21 also includes: The charging sustaining module 215 has a first end connected to the second end of the energy storage module (first energy storage module 211), and the second end of the charging sustaining module 215 is connected to the pull-up node PU. The charging module 214 is used to raise the potential of the pull-up node PU during the pre-charge scanning period, and the charging maintenance module 215 is used to raise the potential of the second terminal of the energy storage module (first energy storage module 211) when the potential of the pull-up node PU is raised and is higher than the potential of the second terminal of the energy storage module (first energy storage module 211).

[0036] For example, such as Figure 4 As shown, the charging module 214 includes a fifth thin-film transistor M1, and the charging sustaining module 215 includes a diode D1. The fifth thin-film transistor M1 is an N-type thin-film transistor that turns on when the potential of the controlled terminal rises. The controlled terminal of the charging module 214 is the gate of the fifth thin-film transistor M1. The first terminal of the charging module 214 is the source of the fifth thin-film transistor M1, and the second terminal of the charging module 214 is the drain of the fifth thin-film transistor M1. The first terminal of the charging sustaining module 215 is the cathode of the diode D1, and the second terminal of the charging sustaining module 215 is the anode of the diode D1.

[0037] For example, such as Figure 4As shown, the first end of the charging module 214 is connected to the fourth power supply terminal VGH, the second end of the charging module 214 is connected to the pull-up node PU, and the controlled end of the charging module 214 is connected to the stage transmission signal terminal of the (n-4)th stage scan drive unit (the stage transmission signal terminal of the (n-4)th stage scan drive unit is represented by Tn-4). The pre-charge scan period includes the pre-charge period and the scan period. Figure 5(b) is a schematic diagram of the potential signal flow of the nth stage scan drive unit during the pre-charge period, and Figure 5(c) is a schematic diagram of the potential signal flow of the nth stage scan drive unit during the scan period. In Figures 5(b) and 5(c), solid lines represent signal transmission, dashed lines represent no signal transmission, dark gray lines represent high-potential signal transmission, and light gray lines represent low-potential signal transmission. As shown in Figures 5(b) and 5(c), when the nth stage scan drive unit enters the pre-charge period or enters the scan period, the potential of the fourth power supply terminal VGH is always at a high potential, which is used to raise the voltage of the first end of the charging module 214. At this time, the potential of the stage transmission signal terminal of the (n-4)th stage scan drive unit (represented by Tn-4) is at a high potential, raising the potential of the controlled terminal of the charging module 214. The charging module 214 is turned on when the potential of the controlled terminal is raised, and the potential of the pull-up node PU is raised when it is turned on. During the pre-charging period, the potential of the third power supply terminal VSS is at a low potential, and the potential of the pull-up node PU is higher than the potential of the second terminal of the energy storage module (first energy storage module 211). The charging maintenance module 215 is turned on when the potential of the pull-up node PU is raised and is higher than the potential of the second terminal of the energy storage module (first energy storage module 211), and the potential of the second terminal of the energy storage module (first energy storage module 211) is raised when it is turned on, so that the first energy storage module 211 stores a portion of electrical energy so that when the display panel enters the shutdown period, the potential of the pull-up node PU is not raised enough, which would prevent the output module 210 from being turned on.

[0038] For example, as shown in Figures 5(b) and 5(c), when the nth-level scan drive unit enters the precharge period or the scan period, the potential of the pull-up node PU rises during both the precharge and scan periods. Therefore, the output module 210 and the cascade module 218 are both turned on during the precharge and scan periods. The difference between the precharge and scan periods is that when the nth-level scan drive unit enters the precharge period, the clock signal terminal CK is at a low potential. Therefore, the output module 210 will not output a scan signal to the nth row scan line Gn, and the second terminal of the cascade module 218 (i.e., the cascade signal terminal of the nth-level scan drive unit, denoted by Tn) will not output a cascade signal. However, when the nth-level scan drive unit enters the scan period, the clock signal terminal CK is at a high potential, the output module 210 will output a scan signal to the nth row scan line Gn, and the second terminal of the cascade module 218 (i.e., the cascade signal terminal of the nth-level scan drive unit, denoted by Tn) will output a cascade signal.

[0039] In one alternative embodiment, such as Figure 4 As shown, the nth-level scanning drive unit 21 further includes: a first reset module 216, the first end of the first reset module 216 being connected to the third power supply terminal VSS, the second end of the first reset module 216 being connected to the pull-up node PU, the third power supply terminal VSS being used to reset the potential of the first end of the first reset module 216 during a blank period, the first reset module 216 being used to reset the potential of the pull-up node PU during the blank period, and the charging sustaining module 215 being used to maintain the potential of the second end of the energy storage module (first energy storage module 211) when the potential of the pull-up node PU is reset.

[0040] For example, such as Figure 4 As shown, the first reset module 216 includes: a sixth thin-film transistor M9, which is an N-type thin-film transistor and is turned on when the potential of the controlled terminal rises. The controlled terminal of the first reset module 216 is the gate of the sixth thin-film transistor M9, the first terminal of the first reset module 216 is the source of the sixth thin-film transistor M9, and the second terminal of the first reset module 216 is the drain of the sixth thin-film transistor M9.

[0041] For example, such as Figure 4As shown, the controlled terminal of the first reset module 216 is connected to the stage transmission signal terminal of the (n+6)th stage scan drive unit (the stage transmission signal terminal of the (n+6)th stage scan drive unit is represented by Tn+6). Figure 5(d) is a schematic diagram of the potential signal flow of the nth stage scan drive unit during the blank period. In Figure 5(d), solid lines represent signal transmission, dashed lines represent no signal transmission, dark gray lines represent high-potential signal transmission, and light gray lines represent low-potential signal transmission. As shown in Figure 5(d), when the nth stage scan drive unit enters the blank period, the third power supply terminal VSS is at a low potential. At this time, the stage transmission signal terminal of the (n+6)th stage scan drive unit (the stage transmission signal terminal of the (n+6)th stage scan drive unit) is connected to the stage transmission signal terminal of the (n+6)th stage scan drive unit. The stage transmission signal terminal of the moving unit (represented by Tn+6) is at a high potential, raising the potential of the controlled terminal of the first reset module 216. The first reset module 216 is turned on when the potential of the controlled terminal is raised and resets the potential of the pull-up node PU when it is turned on and the potential of the first terminal is reset. The charging maintenance module 215 is used to turn off when the potential of the pull-up node PU is reset and maintain the potential of the second terminal of the energy storage module (first energy storage module 211) when it is turned off, thereby maintaining the power in the energy storage module (first energy storage module 211) during the blank period of the last frame driving period (before entering the power-off period).

[0042] In one alternative embodiment, such as Figure 4 As shown, the nth level of the above-mentioned scanning drive unit further includes: The second reset module 217 has its first end connected to the third power supply terminal VSS, its second end connected to the pull-up node PU, and its controlled end connected to the start signal terminal STV or to the transmission signal terminal of the (n-1)th level scan drive unit. Wherein, the third power supply terminal VSS is used to reset the potential of the first terminal of the second reset module 217 during the frame header reset period of the display panel; the start signal terminal STV or the stage transmission signal terminal of the (n-1)th level of the scan drive unit is used to raise the potential of the controlled terminal of the second reset module 217 during the frame header reset period; the second reset module 217 is used to reset the potential of the pull-up node PU when the potential of the controlled terminal is raised; the reset signal terminal CLR is used to raise the potential of the controlled terminal of the charging reset module 213 during the frame header reset period to enable the charging reset module 213; and the charging reset module 213 is used to reset the potential of the second terminal of the energy storage module when the pull-up node PU is reset.

[0043] For example, such as Figure 4As shown, the second reset module 217 includes: a seventh thin-film transistor M15, which is an N-type thin-film transistor and is turned on when the potential of the controlled terminal rises. The controlled terminal of the second reset module 217 is the gate of the seventh thin-film transistor M15, the first terminal of the second reset module 217 is the source of the seventh thin-film transistor M15, and the second terminal of the second reset module 217 is the drain of the seventh thin-film transistor M15.

[0044] For example, such as Figure 4 As shown, if the nth level scan drive unit is the 1st level scan drive unit, then the controlled terminal of the second reset module 217 is connected to the start signal terminal STV; otherwise, the controlled terminal of the second reset module 217 is connected to the transmission signal terminal of the (n-1)th level scan drive unit. Figure 5(e) is a schematic diagram of the potential signal flow of the nth level scan drive unit during the frame header reset period. In Figure 5(e), solid lines represent signal transmission, dashed lines represent no signal transmission, dark gray lines represent high-potential signal transmission, and light gray lines represent low-potential signal transmission. As shown in Figure 5(e), when the nth level scan drive unit enters the frame header reset period, the third power supply terminal VSS is at a low potential. At this time, the start signal terminal STV... When TV is at a high potential, the potential of the controlled terminal of the second reset module 217 is raised. The second reset module 217 is used to turn on when the potential of the controlled terminal is raised, and to reset the potential of the pull-up node PU when it is turned on and the potential of the first terminal is reset. At this time, the reset signal terminal CLR is at a high potential, raising the potential of the controlled terminal of the charging reset module 213 so that the charging reset module 213 is turned on. The charging reset module 213 is used to reset the potential of the second terminal of the energy storage module (first energy storage module 211) when it is turned on and the pull-up node PU is reset, thereby realizing the reset of the energy storage module (first energy storage module 211).

[0045] Embodiments of this application also provide a discharge control method for a display panel, which is applied to any of the above-described display panels. The method includes: Step S101: Detect whether the above-mentioned display panel has entered the above-mentioned power-off period; Step S102: When the display panel enters the shutdown period, the switch circuit is turned on to connect the data line and the discharge terminal, so that the residual charge in the activated pixel unit is released to the discharge terminal through the corresponding data line.

[0046] Through the above embodiments, such as Figure 4As shown, during the power-off period of the display panel, the scanning drive circuit 20 outputs a scanning signal to each scan line, which turns on the corresponding pixel unit 10 and the switching circuit 30. When turned on, the data line is connected to the discharge terminal DIS, so that the residual charge in the turned-on pixel unit 10 is released to the discharge terminal DIS through the corresponding data line. This solves the problem that the pixel unit still has residual charge after the display panel is turned off in the prior art, avoids the situation of image retention after the display panel is turned off, and improves the display quality of the product.

[0047] In an optional embodiment, step S102 above can be implemented as follows: A preset potential signal is output to the first power supply terminal to turn on each discharge control module, so that when the discharge control module is turned on, the corresponding data line is connected to the discharge terminal, and the preset potential signal is less than the turn-on threshold potential of the discharge control module.

[0048] It should be understood that the terminology used herein is for the purpose of describing particular exemplary embodiments only and is not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms “a,” “an,” and “described” as used herein may also include the plural forms. The terms “comprising,” “including,” “containing,” and “having” are inclusive and therefore indicate the presence of the stated features, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components, and / or combinations thereof. The method steps, processes, and operations described herein are not construed as requiring them to be performed in a particular order described or illustrated unless the order of performance is explicitly indicated. It should also be understood that additional or alternative steps may be used.

[0049] The above description is merely a specific embodiment of the present invention, enabling those skilled in the art to understand or implement the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A display panel, characterized in that, The display panel also includes: Scan drive circuit; The system includes a discharge terminal and a switching circuit, wherein the switching circuit is connected to the discharge terminal and to a data line; The scanning drive circuit is used to output a scanning signal to the scanning line during the power-off period of the display panel to turn on the corresponding pixel unit. The switching circuit is used to connect the data line and the discharge terminal during the power-off period so that the residual charge in the turned-on pixel unit is released to the discharge terminal through the corresponding data line. The scan driving circuit includes: P cascaded scan driving units, each scan driving unit being connected to a corresponding row of scan lines, where P is a positive integer; The scan driving unit of the nth level includes: an output module, a clock signal terminal, a third power supply terminal, and a reset signal terminal. The first terminal of the output module is connected to the clock signal terminal, and the second terminal of the output module is connected to the nth scan line, where n is a positive integer less than P. The scan driving unit at level n further includes: An energy storage module, wherein a first end of the energy storage module is connected to the third power supply end; A charging reset module is provided, wherein the first end of the charging reset module is connected to the second end of the energy storage module, the second end of the charging reset module is connected to the controlled end of the output module, and the connection node is a pull-up node connection, and the controlled end of the charging reset module is connected to the reset signal end.

2. The display panel according to claim 1, characterized in that, The switching circuit includes: First power supply terminal; Multiple discharge control modules are provided. The first end of each discharge control module is connected to the discharge terminal. Each discharge control module corresponds to a data line. The second end of each discharge control module is connected to the corresponding data line. The controlled end of each discharge control module is connected to the first power supply terminal. The first power supply terminal is used to lower the potential of the controlled end of the discharge control module during the power-off period so that the potential of the controlled end of the discharge control module is less than the activation threshold potential. The discharge control module is used to connect the corresponding data line to the discharge terminal when the potential of the controlled end is less than the activation threshold potential.

3. The display panel according to claim 2, characterized in that, The discharge terminal is either a ground terminal or a second power supply terminal, with the second power supply terminal used to connect to a constant negative voltage.

4. The display panel according to claim 1, characterized in that, Each of the scan drive units is used to output the scan signal to the corresponding scan line during the power-off period.

5. The display panel according to claim 4, characterized in that, The third power supply terminal is used to raise the potential of the second terminal of the energy storage module during the power-off period, so that the potential of the second terminal of the energy storage module is higher than the potential of the pull-up node. The reset signal terminal is used to raise the potential of the controlled terminal of the charging reset module during the power-off period. The charging reset module is used to turn on when the potential of the controlled terminal is raised, and raise the potential of the pull-up node when the potential of the second terminal of the energy storage module is raised and is higher than the potential of the pull-up node. The clock signal terminal is used to raise the potential of the first terminal of the output module during the power-off period. The output module is used to output the scan signal to the nth scan line when the potential of the pull-up node is raised.

6. The display panel according to claim 5, wherein the nth level scanning driving unit further comprises: The charging module and a fourth power supply terminal are provided. A first terminal of the charging module is connected to the fourth power supply terminal, which is used to raise the potential of the first terminal of the charging module. A second terminal of the charging module is connected to the pull-up node. The nth-level scanning drive unit further includes: A charging sustaining module, wherein a first end of the charging sustaining module is connected to a second end of the energy storage module, and the second end of the charging sustaining module is connected to the pull-up node; The charging module is used to raise the potential of the pull-up node during the pre-charge scan period, and the charging maintenance module is used to raise the potential of the second terminal of the energy storage module when the potential of the pull-up node is raised and is higher than the potential of the second terminal of the energy storage module.

7. The display panel according to claim 6, wherein the nth level scanning driving unit further comprises: A first reset module, wherein a first end of the first reset module is connected to the third power supply terminal, and a second end of the first reset module is connected to the pull-up node, wherein the third power supply terminal is used to reset the potential of the first end of the first reset module during a blank period, the first reset module is used to reset the potential of the pull-up node during the blank period, and the charging sustaining module is used to maintain the potential of the second end of the energy storage module when the potential of the pull-up node is reset.

8. The display panel according to claim 7, characterized in that, The scan driving unit at level n further includes: The second reset module has a first end connected to the third power supply terminal, a second end connected to the pull-up node, and a controlled end connected to the start signal terminal or the transmission signal terminal of the (n-1)th level scan drive unit. Wherein, the third power supply terminal is used to reset the potential of the first terminal of the second reset module during the frame header reset period of the display panel; the start signal terminal or the stage transmission signal terminal of the (n-1)th level scanning drive unit is used to raise the potential of the controlled terminal of the second reset module during the frame header reset period; the second reset module is used to reset the potential of the pull-up node when the potential of the controlled terminal is raised; the reset signal terminal is used to raise the potential of the controlled terminal of the charging reset module during the frame header reset period to enable the charging reset module; and the charging reset module resets the potential of the second terminal of the energy storage module when the pull-up node is reset.

9. A method for controlling discharge of a display panel, characterized in that, The method is applied to the display panel according to any one of claims 1 to 8, and the method includes: Detect whether the display panel has entered the shutdown period; When the display panel enters the power-off period, the switch circuit is turned on to connect the data line and the discharge terminal, so that the residual charge in the activated pixel unit is released to the discharge terminal through the corresponding data line.

10. The method according to claim 9, characterized in that, The switching circuit includes: a first power supply terminal and multiple discharge control modules, which control the switching circuit to turn on, including: A preset potential signal is output to the first power supply terminal to turn on each discharge control module, so that when the discharge control module is turned on, the corresponding data line is connected to the discharge terminal, and the preset potential signal is less than the turn-on threshold potential of the discharge control module.

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