Pixel circuit, driving method thereof and display panel

Abstract

The invention discloses a pixel circuit, a driving method thereof and a display panel. The pixel circuit comprises a driving module, a storage module, a first initialization module, a compensation module, a light emitting module, a light emitting control module and a charge injection module, the first initialization module is used for writing a first initialization voltage provided by a first initialization signal line into the control end of the driving module according to a signal on a first scanning line; the compensation module is used for performing threshold compensation on the driving module according to the signal on the second scanning line; the charge injection module is used for conducting according to a signal on a charge injection control signal line and injecting electrons into the first end of the storage module, and when the neutralization compensation module and / or the first initialization module are / is closed, the electrons are injected into holes in the first end of the storage module. According to the technical scheme provided by the embodiment of the invention, the hole injected into the first end of the storage module at the moment of closing the compensation module and / or the first initialization module can be neutralized, and the uniformity of display brightness is improved.

Description

Technical Field

[0001] The present invention relates to the field of display technology, and in particular to a pixel circuit and a driving method thereof, and a display panel. Background Art

[0002] Organic Light Emitting Diode (OLED) display panels have the characteristics of low power consumption, low production cost and self-luminescence, and have become a hot research topic in the current field.

[0003] The prior art generally adopts a method of compensating the threshold voltage of the pixel circuit to improve the brightness uniformity of the entire display screen. However, in the prior art, at the moment when the compensation module or the first initialization module is turned off, the charge outflow switch tube introduces a voltage jump at the first end of the storage module. At this time, the switch tube has been disconnected, and the error at the first end of the storage module cannot be restored, resulting in poor uniformity of the displayed brightness. Summary of the invention

[0004] The present invention provides a pixel circuit and a driving method thereof and a display panel, which can neutralize holes injected into the first end of a storage module when a compensation module and / or a first initialization module is turned off, thereby improving display effects.

[0005] In a first aspect, an embodiment of the present invention provides a pixel circuit, including: a driving module, a storage module, a first initialization module, a compensation module, a light emitting module, a light emitting control module and a charge injection module;

[0006] The first end of the storage module is connected to the control end of the driving module and is used to store the voltage of the control end of the driving module;

[0007] The light-emitting control module, the driving module and the light-emitting module are connected between the first power supply and the second power supply. The light-emitting control module is used to control the light-emitting module to emit light according to the driving current output by the driving module according to the signal on the light-emitting control signal line.

[0008] A first end of the first initialization module is connected to the first initialization signal line, a second end of the first initialization module is connected to the control end of the driving module, and the first initialization module is used to write a first initialization voltage provided by the first initialization signal line to the control end of the driving module according to a signal on the first scanning line;

[0009] A first end of the compensation module is connected to a first end of the driving module, a second end of the compensation module is connected to a control end of the driving module, and the compensation module is used to perform threshold compensation on the driving module according to a signal on the second scanning line;

[0010] The first end of the charge injection module is connected to the first end of the storage module, and the second end of the charge injection module is connected to the control end of the driving module. The charge injection module is used to turn on the signal on the charge injection control signal line and inject electrons into the first end of the storage module to neutralize the holes injected into the first end of the storage module when the compensation module and / or the first initialization module are turned off.

[0011] Optionally, the charge injection module includes a first transistor; the first electrode of the first transistor serves as the first end of the charge injection module, the second electrode of the first transistor serves as the second end of the charge injection module, the first electrode of the first transistor is connected to the second electrode of the first transistor, and the gate of the first transistor serves as the control end of the charge injection module.

[0012] Optionally, within a frame, a time interval of a pulse of a signal on the charge injection control signal line is within a time interval of a pulse of a signal on the light emitting control signal line.

[0013] Optionally, the light-emitting control module includes a first light-emitting control module and a second light-emitting control module; the first light-emitting control module is connected between the first power supply and the second end of the driving module, the second light-emitting control module is connected between the first end of the driving module and the first end of the light-emitting module, the second end of the light-emitting module is connected to the second power supply, and the control end of the first light-emitting control module and the control end of the second light-emitting control module are connected to the light-emitting control signal line.

[0014] Optionally, the first light-emitting control module includes a second transistor, a first electrode of the second transistor is connected to the first power supply, a second electrode of the second transistor is connected to the second end of the driving module, and a gate of the second transistor is connected to a light-emitting control signal line; the second light-emitting control module includes a third transistor, a first electrode of the third transistor is connected to the first end of the driving module, a second electrode of the third transistor is connected to the first end of the light-emitting module, and a gate of the third transistor is connected to the light-emitting control signal line.

[0015] Optionally, the driving module includes a fourth transistor, the first electrode of the fourth transistor serves as the second end of the driving module, the second electrode of the fourth transistor serves as the first end of the driving module, and the gate of the fourth transistor serves as the control end of the driving module;

[0016] The compensation module includes a fifth transistor, a first electrode of the fifth transistor serves as a first end of the compensation module, a second electrode of the fifth transistor serves as a second end of the compensation module, and a gate of the fifth transistor is connected to the second scan line;

[0017] The first initialization module includes a sixth transistor, a first electrode of the sixth transistor serves as a first end of the first initialization module, a second electrode of the sixth transistor serves as a second end of the first initialization module, and a gate of the sixth transistor is connected to the first scan line.

[0018] The storage module includes a storage capacitor, a first end of the storage capacitor serves as a first end of the storage module, and a second end of the storage capacitor is connected to a first power source.

[0019] Optionally, the pixel circuit further includes a second initialization module and a data writing module;

[0020] The second initialization module includes a seventh transistor, a first electrode of the seventh transistor is connected to the first initialization signal line, a second electrode of the seventh transistor is connected to the first end of the light emitting module, and a gate of the seventh transistor is connected to the second scan line.

[0021] The data writing module comprises an eighth transistor, a first electrode of the eighth transistor is connected to the data signal line, a second electrode of the eighth transistor is connected to the second end of the driving module, and a gate of the eighth transistor is connected to the second scanning line.

[0022] Optionally, the pixel circuit also includes a third initialization module, the third initialization module includes a ninth transistor, the first electrode of the ninth transistor is connected to the second initialization signal line, the second electrode of the ninth transistor is connected to the second end of the driving module, and the gate of the ninth transistor is connected to the third scan line.

[0023] In a second aspect, an embodiment of the present invention provides a method for driving a pixel circuit, which is used in a pixel circuit provided by any embodiment of the present invention. The method for driving a pixel circuit includes:

[0024] In the first initialization stage, the first scanning signal output by the first scanning line controls the first initialization module to be turned on;

[0025] In the threshold compensation stage, the second scanning signal output by the second scanning line controls the compensation module to be turned on, performs threshold compensation on the driving module, and controls the second initialization module to be turned on;

[0026] In the charge injection stage, the charge injection control signal output by the charge injection control signal line controls the charge injection module to be turned on, and injects electrons into the first end of the storage module to neutralize the holes injected into the first end of the storage module when the compensation module and / or the first initialization module are turned off;

[0027] In the light-emitting stage, the light-emitting control signal output by the light-emitting control signal line controls the light-emitting control module to be turned on.

[0028] In a third aspect, an embodiment of the present invention provides a display panel, comprising the pixel circuit provided by any embodiment of the present invention.

[0029] The technical solution provided by the embodiment of the present invention injects electrons into the first end of the storage module through the charge injection module after compensating the threshold voltage of the driving module, and neutralizes the holes injected into the first end of the storage module when the compensation module and / or the first initialization module are turned off. Since the first end of the storage module is connected to the control end of the driving module, when the potential of the first end of the storage module changes, the potential of the control end of the driving module can be fine-tuned to improve the threshold compensation effect, so that the driving module can ensure that the driving current generated by different pixel circuits under the same grayscale voltage is the same under the effect of fine-tuning its control end voltage, so that the light-emitting brightness of the light-emitting module is the same, thereby improving the uniformity of the brightness, which is beneficial to improving the display effect.

[0030] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0032] Figure 1 is a structural schematic diagram of a pixel circuit provided by an embodiment of the present invention;

[0033] Figure 2 is a structural schematic diagram of another pixel circuit provided by an embodiment of the present invention;

[0034] Figure 3 is a structural schematic diagram of another pixel circuit provided by an embodiment of the present invention;

[0035] Figure 4 is a structural schematic diagram of another pixel circuit provided by an embodiment of the present invention;

[0036] Figure 5 is a timing diagram of a charge injection control signal line and a light emission control signal line provided by an embodiment of the present invention;

[0037] Figure 6 is a structural schematic diagram of another pixel circuit provided by an embodiment of the present invention;

[0038] Figure 7 is a structural schematic diagram of another pixel circuit provided by an embodiment of the present invention;

[0039] Figure 8is a structural schematic diagram of another pixel circuit provided by an embodiment of the present invention;

[0040] Fig. 9 is a timing diagram of a pixel circuit provided by an embodiment of the present invention;

[0041] Fig.10 is a flow chart of a driving method of a pixel circuit provided by an embodiment of the present invention;

[0042] Fig.11 is a flow chart of another method for driving a pixel circuit provided by an embodiment of the present invention;

[0043] Fig.12 It is a structural schematic diagram of a display device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0044] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0045] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions.

[0046] As described in the background technology, the pixel circuit in the prior art has the problem of poor brightness uniformity at low grayscale. The inventor has found that the reason for the above problem is that the pixel circuit of the 7T1C architecture is usually used in the prior art to compensate the threshold voltage of the driving module (driving transistor). When the compensation module is turned on, the data voltage associated with the threshold voltage of the driving module is written into the storage capacitor. Therefore, the threshold voltage information of the driving module is stored in the capacitor. However, at the moment when the compensation module or the first initialization module is turned off, the charge flows out of the switch tube, which introduces a voltage jump at the first end of the storage module. At this time, the switch tube has been disconnected, and the error at the first end of the storage module cannot be restored, resulting in the same grayscale. The driving current generated by different driving modules is inconsistent, which makes the display panel have poor brightness uniformity when displaying.

[0047] In view of the above problems, an embodiment of the present invention provides a pixel circuit to increase the uniformity of display brightness and improve the display effect. Figure 1 A schematic diagram of a pixel circuit according to an embodiment of the present invention is provided. Figure 1 The pixel circuit provided by the embodiment of the present invention includes: a driving module 110, a storage module 120, a first initialization module 130, a compensation module 140, a light emitting module 150, a light emitting control module 160 and a charge injection module 170.

[0048] The first end of the storage module 120 is connected to the control end of the driving module 110, and the second end of the storage module 110 is connected to the reference voltage. For example, the second end of the storage module 110 is connected to the first power supply VDD, and the storage module 110 is used to store the voltage of the control end of the driving module 110; the light control module 160, the driving module 110 and the light emitting module 150 are connected between the first power supply VDD and the second power supply VSS, and the light control module 160 is used to control the light emitting module 150 to emit light according to the driving current output by the driving module 110 according to the signal on the light control signal line EM; the first initialization module 13 The first end of the first initialization module 10 is connected to the first initialization signal line VINT1, the second end of the first initialization module 130 is connected to the control end of the driving module 110, and the first initialization module 130 is used to write the first initialization voltage provided by the first initialization signal line VINT1 to the control end of the driving module 110 according to the signal on the first scan line S1; the first end of the compensation module 140 is connected to the first end of the driving module 110, the second end of the compensation module 140 is connected to the control end of the driving module 110, and the compensation module 140 is used to perform threshold compensation on the driving module 110 according to the signal on the second scan line S2.

[0049] The first end of the charge injection module 170 is connected to the first end of the storage module 120, and the second end of the charge injection module 170 is connected to the control end of the driving module 110. The charge injection module 170 is used to be turned on according to the signal on the charge injection control signal line Cn, and inject electrons into the first end of the storage module 120 to neutralize the holes injected into the first end of the storage module 120 when the compensation module 140 and / or the first initialization module 130 are turned off.

[0050] Exemplarily, the light emitting module 150 may be an organic light emitting diode (OLED), the anode of the OLED serving as the first end of the light emitting module 150, and the cathode of the OLED serving as the second end of the light emitting module 150. The light emitting module 150 emits light according to the driving current output by the driving module 110, wherein the driving current may be the driving current output by the driving module 110 according to the voltages at the control end and the second end thereof.

[0051] The pixel circuit further includes a data writing module 190, a first end of the data writing module 190 is connected to the data signal line Vdata, a second end of the data writing module 190 is connected to the second end of the driving module 110, a control end of the data writing module 190 is connected to the second scanning line S2, and the data writing module 190 is used to write the data voltage provided by the data signal line Vdata to the driving module 110 according to the signal on the second scanning line S2. In other words, the data writing module 190 can be turned on or off according to the signal on the second scanning line S2. When turned on, the data voltage provided by the data signal line Vdata is transmitted to the driving module 110 through the turned-on data writing module 190, and the voltage is written to the control end of the driving module 110 through the transmission path of the second end of the driving module 110 and the compensation module 140. Other modules in the embodiment of the present invention can also be turned on or off in response to the signal on the corresponding connected scanning line, thereby transmitting or cutting off the transmission signal.

[0052] In the present embodiment, the pixel circuit may at least include a first initialization stage, a data writing and threshold compensation stage, a charge injection stage, and a light emitting stage during the time of displaying a frame of picture. Exemplarily, in the first initialization stage, the first scanning signal output by the first scanning line S1 controls the first initialization module 130 to be turned on, and the first initialization module 130 transmits the first initialization voltage provided by the first initialization signal line VINT1 to the first end of the storage module 120 to initialize the storage module 120; in the data writing and threshold compensation stage, the data writing module 180, the first initialization module 130, and the compensation module 140 are turned on, and the data voltage on the data signal line Vdata is written to the control end of the driving module 110 through the data writing module 190, the driving module 110, and the compensation module 140. Since the compensation module 140 can compensate the threshold of the driving module 110, The voltage at the control end of the driving module 110 can include a voltage associated with the data voltage and the threshold voltage, thereby realizing the writing of the data voltage and the threshold compensation of the driving module 110; in the charge injection stage, the signal on the first scan line S1 controls the first initialization module 130 to be turned off, and the signal on the second scan line S2 controls the data writing module 190 and the compensation module 140 to be turned off. After a period of time, and before the light-emitting stage, the charge injection control signal output by the charge injection control signal line Cn turns on the hole charge injection module 170, and injects electrons into the first end of the storage module 120, neutralizing the holes injected into the first end of the storage module 120 when the compensation module 140 and / or the first initialization module 130 are turned off. That is to say, when the compensation module 140 and / or the first initialization module 130 are turned off, the charge injection module 170 is turned on, and the channel charge deposited on the storage module 120 when the compensation module 140 and / or the first initialization module 130 are turned on is absorbed by the charge injection module 170 to establish a channel of the charge injection module; in the light-emitting stage, the light-emitting control signal output by the light-emitting control signal line controls the light-emitting control module to be turned on.

[0053] The technical solution provided by the embodiment of the present invention injects electrons into the first end of the storage module through the charge injection module after compensating the threshold voltage of the driving module, and neutralizes the holes injected into the first end of the storage module when the compensation module and / or the first initialization module are turned off. Since the first end of the storage module is connected to the control end of the driving module, when the potential of the first end of the storage module changes, the potential of the control end of the driving module can be fine-tuned to improve the threshold compensation effect, so that the driving module can ensure that the driving current generated by different pixel circuits under the same grayscale voltage is the same under the effect of fine-tuning its control end voltage, so that the light-emitting brightness of the light-emitting module is the same, thereby improving the uniformity of the brightness, which is beneficial to improving the display effect.

[0054] Figure 2 A schematic diagram of another pixel circuit provided by an embodiment of the present invention, referring to Figure 2 On the basis of the above technical solution, the pixel circuit further includes a second initialization module 180, a first end of the second initialization module 180 is connected to the first initialization signal line VINT1, a second end of the second initialization module 180 is connected to the first end of the light emitting module 150, and the second initialization module 180 is used to write the first initialization voltage provided by the first initialization signal line VINT1 to the first end of the light emitting module 150 according to the signal on the second scan line S2. The pixel circuit further includes a third initialization module 200, a first end of the third initialization module 200 is connected to the second initialization signal line VINT2, a second end of the third initialization module 200 is connected to the first end of the light emitting module 150, and the third initialization module 200 is used to write the second initialization voltage provided by the second initialization signal line VINT2 to the first end of the light emitting module 150 according to the signal on the third scan line S3.

[0055] Specifically, the working process of the pixel circuit may include five stages. In the first stage (the first initialization stage), the signal on the first scanning line S1 controls the first initialization module 130 to turn on, and the first initialization voltage provided by the first initialization signal line VINT1 is written into the control end of the driving module 110 through the first initialization module 130, thereby realizing the initialization of the control end of the driving module 110 in the first stage.

[0056] In the second stage (data voltage writing and threshold compensation stage), the signal transmitted by the first scan line S1 controls the first initialization module 130 to be turned off, the signal on the second scan line S2 controls the data writing module 190 and the compensation module 140 to be turned on, and the data voltage provided by the data signal line Vdata is written to the control end of the driving module 110 through the data writing module 190, the driving module 110 and the compensation module 140. Since the compensation module 140 can compensate the threshold of the driving module 110, the voltage at the control end of the driving module 110 can include a voltage associated with the data voltage and the threshold voltage, thereby realizing the writing of the data voltage and the threshold compensation of the driving module 110. At the same time, in the second stage, the signal on the second scan line S2 controls the second initialization module 180 to be turned on, and the first initialization voltage provided by the first initialization signal line VINT1 is written to the first end of the light emitting module 150 through the second initialization module 180, so as to realize the initialization of the first end of the light emitting module 150 in the second stage, thereby avoiding the influence of the residual charge at the first end of the light emitting module 150 on the display effect.

[0057] In the third stage (the second initialization stage), the signal on the first scan line S1 controls the first initialization module 130 to turn off, the signal on the second scan line S2 controls the data writing module 190, the compensation module 140 and the second initialization module 180 to turn off, the signal on the third scan line S3 controls the third initialization module 200 to turn on, and the second initialization voltage provided by the second initialization signal line VINT2 is written into the second end of the driving module 110 through the third initialization module 200. In the third stage, the second end of the driving module 110 is initialized to avoid the influence of the residual charge at the second end of the driving module 110 on the display effect.

[0058] In the fourth stage (charge injection stage), the signal on the first scan line S1 controls the first initialization module 130 to turn off, the signal on the second scan line S2 controls the data writing module 190, the compensation module 140 and the second initialization module 180 to turn off, and the signal on the third scan line S3 controls the third initialization module 200 to turn off. After a period of time, the charge injection control signal output by the charge injection control signal line Cn turns on the hole charge injection module 170, and injects electrons into the first end of the storage module 120 to neutralize the holes injected into the first end of the storage module when the compensation module 140 and / or the first initialization module 130 are turned off. That is, when the compensation module 140 and / or the first initialization module 130 are turned off, the charge injection module 170 is turned on, and the channel charge deposited on the storage module 120 when the compensation module 140 and / or the first initialization module 130 are turned on is absorbed by the charge injection module 170 to establish the channel of the charge injection module 170.

[0059] In the fifth stage (light-emitting stage), the signal on the first scan line S1 controls the first initialization module 130 to turn off, the signal on the second scan line S2 controls the data writing module 190, the compensation module 140 and the second initialization module 180 to turn off, the signal on the light-emitting control signal line EM controls the light-emitting control module 160 to turn on, the light-emitting control module 160 transmits the voltage on the first power supply Vdd to the second end of the driving module 110, and the driving module 110 outputs a driving current to drive the light-emitting module 150 to emit light.

[0060] Figure 3 A schematic diagram of another pixel circuit provided in an embodiment of the present invention. Figure 2 Based on the examples, refer to Figure 3 Optionally, the charge injection module 170 includes a first transistor T1; the first electrode of the first transistor T1 serves as the first end of the charge injection module 170, the second electrode of the first transistor T1 serves as the second end of the charge injection module 170, the first electrode of the first transistor T1 is connected to the second electrode of the first transistor T1, and the gate of the first transistor T1 serves as the control end of the charge injection module 170.

[0061] Figure 4 A schematic diagram of another pixel circuit provided in an embodiment of the present invention. Figure 2 Based on the examples, refer to Figure 4 The light-emitting control module 160 includes a first light-emitting control module 610 and a second light-emitting control module 620; the first light-emitting control module 610 is connected between the first power supply VDD and the second end of the driving module 110, the second light-emitting control module 620 is connected between the first end of the driving module 110 and the first end of the light-emitting module 150, the second end of the light-emitting module 150 is connected to the second power supply VSS, and the control end of the first light-emitting control module 610 and the control end of the second light-emitting control module 620 are connected to the light-emitting control signal line EM.

[0062] In the first, second, third and fourth stages of the pixel circuit, the first light-emitting control module 610 and the second light-emitting control module 620 are turned off under the control of the light-emitting control signal line EM. In the fifth stage, the first light-emitting control module 610 and the second light-emitting control module 620 are turned on under the control of the light-emitting control signal line EM, and the voltage provided by the first power supply Vdd is written to the second end of the driving module 110 through the first light-emitting control module 610, and the driving module 110 drives the light-emitting module 150 to emit light according to the voltage of its control end and the voltage of the second end.

[0063] The first light emitting control module 610 includes a second transistor T2, a first electrode of the second transistor T2 is connected to the first power source VDD, a second electrode of the second transistor T2 is connected to the second end of the driving module 110, and a gate of the second transistor T2 is connected to the light emitting control signal line EM.

[0064] The second light emitting control module 620 includes a third transistor T3, a first electrode of the third transistor T3 is connected to the first end of the driving module 110, a second electrode of the third transistor T3 is connected to the first end of the light emitting module 150, and a gate of the third transistor T3 is connected to the light emitting control signal line EM.

[0065] Figure 5 A timing diagram of a charge injection control signal line and a light emission control signal line provided by an embodiment of the present invention, Figure 5 The timing diagram shown is applicable to Figure 4 The pixel circuit shown. Figure 4 and Figure 5 Optionally, within a frame, the time interval of the pulse of the signal on the charge injection control signal line Cn is within the time interval of the pulse of the signal on the light emitting control signal line EM.

[0066] Exemplarily, the charge injection module 170 is turned on when the signal on the light-emitting control signal line Cn is at a low level, and is turned off when the signal on the light-emitting control signal line EM is at a low level, and is turned off when the signal on the light-emitting control signal line EM is at a high level. In the first stage t1, the second stage t2, the third stage t3, and the fourth stage t4, the signal on the light-emitting control signal line EM is at a high level, and the light-emitting control module 160 is turned off. In part of the fourth stage t4 and the fifth stage t5, the signal on the charge injection control signal line Cn is at a low level, and the charge injection module 170 is turned on, so that in part of the fourth stage t4 and the fifth stage t5, the charge injection module 170 injects electrons into the first end of the storage module 120, and neutralizes the holes injected into the first end of the storage module 120 when the compensation module 140 and / or the first initialization module 130 are turned off. The on time interval of the charge injection module 170 is within the off time interval of the light control module 160, so that in the first stage t1 and the second stage t2 when the charge injection module 170 is on, the light control module 600 is in the off state, so as to avoid the light control module 160 being turned on in the first stage t1, the second stage t2, the third stage t3 and the fourth stage t4, thereby causing the light module 150 to be turned on, and the light module 150 is lit before the first end of the storage module 110 completes the charge injection, which will affect the display quality. Therefore, the time interval of the pulse of the signal on the charge injection control signal line Cn is within the time interval of the pulse of the signal on the light control signal line EM, which can ensure that the light module 150 is lit after the charge injection is completed at the first end of the storage module 120, which is conducive to improving the display quality.

[0067] Figure 6 A schematic diagram of another pixel circuit provided in an embodiment of the present invention. Figure 2 Based on the examples, refer to Figure 6 Optionally, the driving module 110 includes a fourth transistor T4, a first electrode of the fourth transistor T4 serves as the second end of the driving module 110, a second electrode of the fourth transistor T4 serves as the first end of the driving module 110, and a gate of the fourth transistor T4 serves as the control end of the driving module 110.

[0068] The compensation module 140 includes a fifth transistor T5 , a first electrode of the fifth transistor T5 serves as a first end of the compensation module 140 , a second electrode of the fifth transistor T5 serves as a second end of the compensation module 140 , and a gate of the fifth transistor T5 is connected to the second scan line S2 .

[0069] The first initialization module 130 includes a sixth transistor T6 , a first electrode of the sixth transistor T6 serves as a first end of the first initialization module 130 , a second electrode of the sixth transistor T6 serves as a second end of the first initialization module 130 , and a gate of the sixth transistor T6 is connected to the first scan line S1 .

[0070] The storage module 120 includes a storage capacitor Cst, a first end of the storage capacitor Cst serves as a first end of the storage module 120, and a second end of the storage capacitor Cst is connected to a first power source VDD.

[0071] The fifth transistor T5 and the sixth transistor T6 are double-gate transistors.

[0072] Specifically, the fifth transistor T5 includes a first double-gate transistor T51 and a second double-gate transistor T52 , and the sixth transistor T6 includes a third double-gate transistor T61 and a fourth double-gate transistor T62 .

[0073] Figure 7 A schematic diagram of another pixel circuit provided by an embodiment of the present invention, referring to Figure 7 In this embodiment, Figure 2 Based on the embodiment, optionally, the second initialization module 180 includes a seventh transistor T7, a first electrode of the seventh transistor T7 is connected to the first initialization signal line VINT1, a second electrode of the seventh transistor T7 is connected to the first end of the light emitting module 150, and a gate of the seventh transistor T7 is connected to the second scan line S2.

[0074] The data writing module 190 includes an eighth transistor T8, a first electrode of the eighth transistor T8 is connected to the data signal line Vdata, a second electrode of the eighth transistor T8 is connected to the second end of the driving module 110, and a gate of the eighth transistor T8 is connected to the second scan line.

[0075] The pixel circuit also includes a third initialization module 200, which includes a ninth transistor T9, a first electrode of which is connected to the second initialization signal line VINT2, a second electrode of which is connected to the second end of the driving module 150, and a gate of which is connected to the third scan line.

[0076] Figure 8 FIG. 1 is a schematic diagram of another pixel circuit provided in an embodiment of the present invention. Based on the above embodiments, this embodiment refers to Figure 8 The pixel circuit includes: a driving module 110, a storage module 120, a first initialization module 130, a compensation module 140, a light emitting module 150, a light emitting control module 160, a charge injection module 170, a second initialization module 180, a data writing module 190 and a third initialization module 190.

[0077] The charge injection module 170 includes a first transistor T1; the light-emitting control module 160 includes a first light-emitting control module 610 and a second light-emitting control module 620, the first light-emitting control module 610 includes a second transistor T2, and the second light-emitting control module 620 includes a third transistor T3; the driving module 110 includes a fourth transistor; the compensation module 140 includes a fifth transistor T5; the first initialization module 130 includes a sixth transistor T6; the second initialization module 180 includes a seventh transistor T7; the data writing module 190 includes an eighth transistor T8; the third initialization module 200 includes a ninth transistor T9; and the storage module 120 includes a storage capacitor Cst.

[0078] The transistors included in the pixel circuit may be P-type transistors or N-type transistors. Figure 7 In the figure, each transistor is a P-type transistor as an example, the first electrode of each transistor can be a drain or a source, and the second electrode of each transistor can be a drain or a source, which is not specifically limited in the embodiment of the present invention.

[0079] Fig. 9 A timing diagram of a pixel circuit provided by an embodiment of the present invention, Figure 8 The timing diagram shown is applicable to Figure 8 Pixel circuit. Figure 8 and Fig. 9 , exemplarily, the driving process of the pixel circuit includes multiple stages.

[0080] In the first stage t1 (first initialization stage), the signal on the first scan line S1 is at a low level, the sixth transistor T6 is turned on, and the first initialization voltage provided by the first initialization signal line VINT1 is transmitted to the gate of the fourth transistor T4 through the sixth transistor T6, thereby resetting the gate of the fourth transistor T4. After the reset is completed, the signal on the first scan line S1 rises to a high level, and the sixth transistor T6 is turned off. In the first stage t1, the signal on the light emitting control signal line EM, the signal on the charge injection control signal line Cn, the second scan line S2, and the third scan line S3 are at a high level, and the first transistor T1, the second transistor T2, the third transistor T3, the fifth transistor T5, the seventh transistor T7, the eighth transistor T8, and the ninth transistor T9 are in the off state.

[0081] In the second stage t2 (data voltage writing and threshold compensation stage), the signal on the second scan line S2 is at a low level, the fifth transistor T5 and the eighth transistor T8 are turned on, and the data voltage on the data signal line Vdata is written to the gate of the fourth transistor T4 through the eighth transistor T8, the fourth transistor T4 and the fifth transistor T5, so as to realize the writing of the data voltage to the gate of the fourth transistor T4 and the compensation of the threshold voltage of the fourth transistor T4, and in the second stage t2, since the signal on the second scan line S2 is at a low level, the seventh transistor T7 is turned on, and the first initialization voltage provided by the first initialization signal line VINT1 is transmitted to the first end of the light emitting module 150 through the seventh transistor T7, so as to reset the first end of the light emitting module 150, thereby avoiding the influence of the residual charge at the first end of the light emitting module 150 on the display effect.

[0082] In the third stage t3 (the second initialization stage), the signals on the first scan line S1 and the second scan line S2 are at a high level, the fifth transistor T5, the sixth transistor T6, the seventh transistor T7 and the eighth transistor T8 are turned off, and the signal on the third scan line S3 is at a low level, which controls the ninth transistor T9 to be turned on, and the second initialization voltage provided by the second initialization signal line VINT2 is written into the second electrode of the fourth transistor T4 through the ninth transistor T9, so that the second electrode of the fourth transistor T4 is initialized in the third stage, thereby avoiding the influence of the residual charge at the second end of the driving module 110 on the display effect.

[0083] In the fourth stage t4 (charge injection stage), including the first sub-stage and the second sub-stage, in the first sub-stage, the signals on the first scan line S1, the second scan line S2 and the third scan line S3 are all high level, and the fifth transistor T5, the sixth transistor T6, the seventh transistor T7, the eighth transistor T8 and the ninth transistor T9 are turned off; in the second sub-stage, the signal on the charge injection control signal line Cn is low level, the first transistor T1 is turned on, and electrons are injected into the first end of the storage capacitor Cst, and the holes injected into the first end of the storage capacitor Cst when the fifth transistor T5 and / or the sixth transistor T6 are turned off. That is, when the fifth transistor T5 and / or the sixth transistor T6 are turned off, the first transistor T1 is turned on, and the channel charge deposited on the storage capacitor Cst when the fifth transistor T5 and / or the sixth transistor T6 are turned on is absorbed by the first transistor T1 to establish the channel of the charge injection module.

[0084] In the fifth stage t5 (light-emitting stage), the signals on the first scan line S1, the second scan line S2 and the third scan line are high level, the fifth transistor T5, the sixth transistor T6, the seventh transistor T7, the eighth transistor T8 and the ninth transistor T9 are turned off, the signal on the light-emitting control signal line EM is low level, the second transistor T2 and the third transistor T3 are turned on, and the voltage on the first power supply VDD is transmitted to the first electrode of the fourth transistor T4 through the second transistor T2, and the fourth transistor T4 drives the light-emitting module 150 to emit light according to the voltage of its gate and the voltage of the first electrode.

[0085] It should be understood that the technical solutions provided in any embodiment of the present invention can be combined with each other to achieve the effect of improving the compensation effect and enhancing the uniformity of display brightness.

[0086] Optionally, an embodiment of the present invention further provides a driving method for a pixel circuit. Fig.10 A flowchart of a driving method of a pixel circuit provided in an embodiment of the present invention is used for a pixel circuit provided in any embodiment of the present invention. For example, refer to Figure 1 and 10 , a driving method of a pixel circuit provided by an embodiment of the present invention includes:

[0087] S101 . In a first initialization stage, a first scanning signal output by a first scanning line controls a first initialization module to be turned on.

[0088] S102 , in the threshold compensation stage, the second scanning signal output by the second scanning line controls the compensation module to be turned on, performs threshold compensation on the driving module, and controls the second initialization module to be turned on.

[0089] S103, in the charge injection stage, the charge injection control signal output by the charge injection control signal line controls the charge injection module to be turned on, and injects electrons into the first end of the storage module to neutralize the holes injected into the first end of the storage module when the compensation module and / or the first initialization module are turned off.

[0090] S104, in the light-emitting stage, the light-emitting control signal output by the light-emitting control signal line controls the light-emitting control module to be turned on.

[0091] The driving method of the pixel circuit is applicable to the pixel circuit provided by any embodiment of the present invention. The specific control method thereof can refer to the above-mentioned related description and will not be repeated here.

[0092] The driving method of the pixel circuit provided by the embodiment of the present invention injects electrons into the first end of the storage module through the charge injection module after compensating the threshold voltage of the driving module, and neutralizes the holes injected into the first end of the storage module when the compensation module and / or the first initialization module are turned off. Since the first end of the storage module is connected to the control end of the driving module, when the potential of the first end of the storage module changes, the potential of the control end of the driving module can be fine-tuned to improve the threshold compensation effect, so that the driving module can ensure that the driving current generated by different pixel circuits under the same grayscale voltage is the same under the effect of fine-tuning its control end voltage, so that the light-emitting brightness of the light-emitting module is the same, thereby improving the uniformity of the brightness, which is conducive to improving the display effect.

[0093] Further, Fig.11 A flowchart of another pixel circuit driving method provided by an embodiment of the present invention, referring to Figure 8 and 11 , the driving method of the pixel circuit includes:

[0094] S201 , in a first initialization stage, a first scan signal output by a first scan line controls the sixth transistor to be turned on.

[0095] S202, in the data voltage writing and threshold compensation stage, the second scan signal output by the second scan line controls the sixth transistor to be turned on, performs threshold compensation on the fourth transistor, and controls the seventh transistor to be turned on.

[0096] S203 , in the second initialization stage, the third scan signal output by the third scan line controls the ninth transistor to be turned on, and the first electrode of the fourth transistor is reset.

[0097] S204, in the charge injection stage, the charge injection control signal output by the charge injection control signal line controls the first transistor to turn on, and injects electrons into the first end of the storage capacitor, neutralizing the holes injected into the first end of the storage capacitor when the fifth transistor and / or the sixth transistor are turned off.

[0098] S205 , in the light-emitting stage, the light-emitting control signal output by the light-emitting control signal line controls the light-emitting control module to be turned on.

[0099] An embodiment of the present invention further provides a display panel, which includes any one of the above pixel circuits.

[0100] An embodiment of the present invention further provides a display device, Fig.12 A schematic diagram of a display device according to an embodiment of the present invention is provided. Fig.12 The display device 01 includes the above-mentioned display panel 02. The display device 01 can be Fig.12The mobile phone shown may also be a computer, a television, a smart wearable display device, etc., and the embodiments of the present invention do not specifically limit this.

[0101] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A pixel circuit, characterized in that: include: A driving module, a storage module, a first initialization module, a compensation module, a light emitting module, a light emitting control module and a charge injection module; The first end of the storage module is connected to the control end of the driving module and is used to store the voltage of the control end of the driving module; The light-emitting control module, the driving module and the light-emitting module are connected between a first power source and a second power source, and the light-emitting control module is used to control the light-emitting module to emit light according to a driving current output by the driving module according to a signal on a light-emitting control signal line; A first end of the first initialization module is connected to a first initialization signal line, a second end of the first initialization module is connected to a control end of the driving module, and the first initialization module is used to write a first initialization voltage provided by the first initialization signal line to the control end of the driving module according to a signal on the first scan line; The first end of the compensation module is connected to the first end of the driving module, the second end of the compensation module is connected to the control end of the driving module, and the compensation module is used to perform threshold compensation on the driving module according to the signal on the second scan line; The first end of the charge injection module is connected to the first end of the storage module, and the second end of the charge injection module is connected to the control end of the driving module. The charge injection module is used to turn on the signal on the charge injection control signal line and inject electrons into the first end of the storage module to neutralize the holes injected into the first end of the storage module when the compensation module and / or the first initialization module are turned off.

2. The pixel circuit according to claim 1, characterized in that: The charge injection module includes a first transistor; The first electrode of the first transistor serves as the first end of the charge injection module, the second electrode of the first transistor serves as the second end of the charge injection module, the first electrode of the first transistor is connected to the second electrode of the first transistor, and the gate of the first transistor serves as the control end of the charge injection module.

3. The pixel circuit according to claim 1, characterized in that: In one frame, the time interval of the pulse of the signal on the charge injection control signal line is within the time interval of the pulse of the signal on the light emission control signal line.

4. The pixel circuit according to claim 1, characterized in that: The light-emitting control module includes a first light-emitting control module and a second light-emitting control module; the first light-emitting control module is connected between the first power supply and the second end of the driving module, the second light-emitting control module is connected between the first end of the driving module and the first end of the light-emitting module, the second end of the light-emitting module is connected to the second power supply, and the control end of the first light-emitting control module and the control end of the second light-emitting control module are connected to a light-emitting control signal line.

5. The pixel circuit according to claim 4, characterized in that: The first light emitting control module comprises a second transistor, a first electrode of the second transistor is connected to the first power supply, a second electrode of the second transistor is connected to the second end of the driving module, and a gate of the second transistor is connected to the light emitting control signal line; The second light emitting control module comprises a third transistor, a first electrode of the third transistor is connected to the first end of the driving module, a second electrode of the third transistor is connected to the first end of the light emitting module, and a gate of the third transistor is connected to the light emitting control signal line.

6. The pixel circuit according to claim 1, characterized in that: The driving module comprises a fourth transistor, the first electrode of the fourth transistor serves as the second end of the driving module, the second electrode of the fourth transistor serves as the first end of the driving module, and the gate of the fourth transistor serves as the control end of the driving module; The compensation module comprises a fifth transistor, a first electrode of the fifth transistor serves as a first end of the compensation module, a second electrode of the fifth transistor serves as a second end of the compensation module, and a gate of the fifth transistor is connected to the second scan line; The first initialization module includes a sixth transistor, a first electrode of the sixth transistor serves as a first end of the first initialization module, a second electrode of the sixth transistor serves as a second end of the first initialization module, and a gate of the sixth transistor is connected to the first scan line. The storage module includes a storage capacitor, a first end of the storage capacitor serves as a first end of the storage module, and a second end of the storage capacitor is connected to a first power source.

7. The pixel circuit according to claim 1, characterized in that: Also includes a second initialization module and a data writing module; The second initialization module includes a seventh transistor, a first electrode of the seventh transistor is connected to the first initialization signal line, a second electrode of the seventh transistor is connected to the first end of the light emitting module, and a gate of the seventh transistor is connected to the second scan line. The data writing module comprises an eighth transistor, a first electrode of the eighth transistor is connected to the data signal line, a second electrode of the eighth transistor is connected to the second end of the driving module, and a gate of the eighth transistor is connected to the second scanning line.

8. The pixel circuit according to claim 7, characterized in that: It also includes a third initialization module, which includes a ninth transistor, a first electrode of the ninth transistor is connected to the second initialization signal line, a second electrode of the ninth transistor is connected to the second end of the driving module, and a gate of the ninth transistor is connected to the third scanning line.

9. A method for driving a pixel circuit, characterized in that: For the pixel circuit according to any one of claims 1 to 8, the driving method of the pixel circuit comprises: In the first initialization stage, the first scanning signal output by the first scanning line controls the first initialization module to be turned on; In the threshold compensation stage, the second scanning signal output by the second scanning line controls the compensation module to be turned on, performs threshold compensation on the driving module, and controls the second initialization module to be turned on; In the charge injection stage, the charge injection control signal output by the charge injection control signal line controls the charge injection module to be turned on, and injects electrons into the first end of the storage module, neutralizing the holes injected into the first end of the storage module when the compensation module and / or the first initialization module are turned off; In the light-emitting stage, the light-emitting control signal output by the light-emitting control signal line controls the light-emitting control module to be turned on.

10. A display panel, characterized in that: The pixel circuit comprises the pixel circuit described in any one of claims 1 to 8.

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