Pixel circuit and driving method thereof and display panel

Abstract

The embodiment of the present invention discloses a pixel circuit and a driving method thereof and a display panel. The pixel circuit includes a driving module, a first light-emitting control module, a light-emitting module and a first initialization module. The first light-emitting control module is connected between a first power line and a first end of the driving module, and the light-emitting module is connected between a second end of the driving module and a second power line. The first light-emitting control module and the first initialization module are used to be turned on in the initialization stage, so as to write an initialization voltage transmitted by a first initialization signal line to a control end of the driving module through the first initialization module, thereby controlling the driving module to be turned on, and forming a current path from the first power line to the first light-emitting control module, the driving module and the first initialization module to the first initialization signal line in sequence. The technical solution of the embodiment of the present invention helps to improve the display uniformity of the display panel, thereby improving the display effect.

Description

Technical Field

[0001] The embodiments of the present invention relate 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] With the continuous development of display technology, people have higher and higher requirements for the performance of display panels. Existing display panels usually include multiple pixel circuits and light-emitting devices, and the pixel circuits drive the light-emitting devices to emit light for display. However, existing display panels have the problem of uneven display, which affects the display effect of the display panel. Summary of the invention

[0003] The embodiments of the present invention provide a pixel circuit and a driving method thereof and a display panel, so as to enhance the display uniformity of the display panel and thus improve the display effect.

[0004] In a first aspect, an embodiment of the present invention provides a pixel circuit, including:

[0005] A driving module, a first light-emitting control module and a light-emitting module, wherein the first light-emitting control module is connected between a first power line and a first end of the driving module, the light-emitting module is connected between a second end of the driving module and a second power line, and the driving module is used to generate a driving current according to a voltage at its control end to drive the light-emitting module to emit light;

[0006] A first initialization module is connected to a first initialization signal line, a control end of the driving module and a second end of the driving module. The first light-emitting control module and the first initialization module are used to be turned on in an initialization stage, so as to write an initialization voltage transmitted by the first initialization signal line to the control end of the driving module through the first initialization module, thereby controlling the driving module to be turned on, and forming a current path from the first power line to the first light-emitting control module, the driving module and the first initialization module to the first initialization signal line in sequence.

[0007] Optionally, the first initialization module includes a first initialization unit and a second initialization unit;

[0008] The control end of the first initialization unit is connected to the first scan line, the first initialization unit is connected between the first initialization signal line and the control end of the driving module, and the first initialization unit is used to respond to the signal transmitted by the first scan line and turn on in the initialization stage to write the initialization voltage transmitted by the first initialization signal line into the control end of the driving module, thereby controlling the driving module to turn on;

[0009] The control end of the second initialization unit is connected to the first scan line, the second initialization unit is connected between the first initialization signal line and the second end of the driving module, and the second initialization unit is used to respond to the signal transmitted by the first scan line and be turned on during the initialization stage to form a current path from the first power line to the first initialization signal line via the first light-emitting control module, the driving module and the second initialization unit in sequence.

[0010] Optionally, the first initialization unit includes a first transistor, and the second initialization unit includes a second transistor;

[0011] The gate of the first transistor is connected to the first scan line, the first electrode of the first transistor is connected to the first initialization signal line, and the second electrode of the first transistor is connected to the control end of the driving module;

[0012] The gate of the second transistor is connected to the first scan line, the first electrode of the second transistor is connected to the first initialization signal line, and the second electrode of the second transistor is connected to the second end of the driving module;

[0013] Preferably, the second transistor comprises an Indium Gallium Zinc Oxide transistor.

[0014] Optionally, the pixel circuit further includes:

[0015] a second light-emitting control module connected between the second end of the driving module and the light-emitting module, and used to connect the driving module and the light-emitting module, or disconnect the driving module and the light-emitting module;

[0016] The control end of the first light-emitting control module is connected to the first light-emitting control signal line, and the control end of the second light-emitting control module is connected to the second light-emitting control signal line;

[0017] The first light-emitting control signal line is configured to input a conduction level signal in the initialization stage, and the second light-emitting control signal line is configured to input a shutoff level signal in the initialization stage, so as to control the first light-emitting control module to be turned on in the initialization stage, and the second light-emitting control module to be turned off in the initialization stage;

[0018] Optionally, the second light-emitting control module includes a fourth transistor, a gate of the fourth transistor is connected to the second light-emitting control signal line, a first electrode of the fourth transistor is connected to the second end of the driving module, and a second electrode of the fourth transistor is connected to the first end of the light-emitting module.

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

[0020] The data writing module is connected between the data line and the driving module, and is used to write the data voltage transmitted by the data line into the driving module;

[0021] The storage module is connected to the control end of the driving module, and the storage module is used to store the voltage of the control end of the driving module;

[0022] The second initialization module is connected between the second initialization signal line and the first end of the light emitting module, and the second initialization module is used to write the signal transmitted by the second initialization signal line to the first end of the light emitting module;

[0023] Preferably, the pixel circuit further includes a threshold compensation module, the data writing module is connected to the first end of the driving module, the threshold compensation module is connected between the second end of the driving module and the control end of the driving module, and the threshold compensation module is used to compensate for the threshold voltage of the driving module.

[0024] Optionally, the data writing module comprises a third transistor, a gate of the third transistor is connected to the second scanning line, and the third transistor is connected between the data line and the driving module;

[0025] The storage module comprises a storage capacitor, a first electrode of the storage capacitor is connected to a fixed voltage, and a second electrode of the storage capacitor is connected to a control terminal of the driving module;

[0026] The second initialization module includes a fifth transistor, a gate of the fifth transistor is connected to the third scan line, a first electrode of the fifth transistor is connected to the second initialization signal line, and a second electrode of the fifth transistor is connected to the first end of the light emitting module;

[0027] The threshold compensation module includes a sixth transistor, a first electrode of the third transistor is connected to the data line, a second electrode of the third transistor is connected to the first end of the driving module, a gate of the sixth transistor is connected to a fourth scan line, a first electrode of the sixth transistor is connected to the second end of the driving module, and a second electrode of the sixth transistor is connected to the control end of the driving module.

[0028] Optionally, the driving module includes a driving transistor, the first light-emitting module includes a seventh transistor, and the light-emitting module includes a light-emitting device;

[0029] The gate of the seventh transistor is connected to the first light-emitting control signal line, the first electrode of the seventh transistor is connected to the first power line, the second electrode of the seventh transistor is connected to the first electrode of the driving transistor, and the light-emitting device is connected between the second electrode of the driving transistor and the second power line.

[0030] In a second aspect, an embodiment of the present invention provides a driving method for a pixel circuit, wherein the pixel circuit comprises: a driving module, a first light-emitting control module, a light-emitting module and a first initialization module; the first light-emitting control module is connected between a first power line and a first end of the driving module, the light-emitting module is connected between a second end of the driving module and a second power line, the driving module is used to generate a driving current according to a voltage at its control end to drive the light-emitting module to emit light; the first initialization module is connected to a first initialization signal line, a control end of the driving module and a second end of the driving module;

[0031] The driving method of the pixel circuit comprises:

[0032] During the initialization stage, the first light-emitting control module and the first initialization module are controlled to be turned on, so that the initialization voltage transmitted by the first initialization signal line is written to the control end of the driving module through the first initialization module, thereby controlling the driving module to be turned on, forming a current path from the first power line through the first light-emitting control module, the driving module and the first initialization module to the first initialization signal line in sequence.

[0033] Optionally, the first initialization module includes a first initialization unit and a second initialization unit; the control end of the first initialization unit is connected to the first scan line, and the first initialization unit is connected between the first initialization signal line and the control end of the driving module; the control end of the second initialization unit is connected to the first scan line, and the second initialization unit is connected between the first initialization signal line and the second end of the driving module;

[0034] In the initialization stage, the first light-emitting control module and the first initialization module are controlled to be turned on, so that the initialization voltage transmitted by the first initialization signal line is written to the control end of the driving module through the first initialization module, thereby controlling the driving module to be turned on, and forming a current path from the first power line to the first initialization signal line via the first light-emitting control module, the driving module and the first initialization module in sequence, including:

[0035] During the initialization stage, a conduction level signal is supplied to the first scan line to control the conduction of the first initialization unit and the second initialization unit, and the initialization voltage transmitted by the first initialization signal line is written into the control end of the driving module through the first initialization unit, thereby controlling the conduction of the driving module and forming a current path from the first power line to the first initialization signal line via the first light-emitting control module, the driving module and the second initialization unit in sequence.

[0036] In a third aspect, an embodiment of the present invention provides a display panel, comprising the pixel circuit described in the first aspect.

[0037] The pixel circuit and its driving method and display panel provided by the embodiment of the present invention control the first light-emitting control module and the first initialization module to be turned on during the initialization stage, so that the initialization voltage transmitted by the first initialization signal line is written into the control end of the driving module through the first initialization module, the control end voltage of the driving module is reset, and the driving module is controlled to be turned on to form a current path from the first power line to the first light-emitting control module, the driving module and the first initialization module to the first initialization signal line in sequence, so that current passes through the driving module, thereby resetting the voltage of the first end and the second end of the driving module, and further resetting the amount of charge captured by the driving module. The advantage of such a setting is that during the initialization stage of each display frame, the control end voltage of the driving module and the amount of charge captured by the driving module can be reset, so that the driving modules in each pixel circuit are in the same state, so that the characteristics of the driving modules in each pixel circuit tend to be consistent, which helps to avoid the state of the driving module in the current display frame being affected by the previous display frame, thereby improving the display uniformity of the display picture and improving the display effect.

[0038] In addition, compared with the prior art, the pixel circuit provided in the embodiment of the present invention only includes a driving module, a first light-emitting control module, a light-emitting module and a first initialization module, so that the overall structure of the pixel circuit is simple, which helps to improve the aperture ratio of the display panel. In the initialization stage, by controlling the first light-emitting control module, the driving module and the first initialization module to be turned on, a current path that flows through the first light-emitting control module, the driving module and the first initialization module in sequence can be formed between the first power line and the first initialization signal line, so that the number of modules passed by the current path is small, which helps to improve the reset effect of the driving module, thereby further improving the display uniformity.

[0039] 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

[0040] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. 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.

[0041] Figure 1 is a structural schematic diagram of a pixel circuit provided by an embodiment of the present invention;

[0042] Figure 2 is a structural schematic diagram of another pixel circuit provided by an embodiment of the present invention;

[0043] Figure 3 is a structural schematic diagram of another pixel circuit provided by an embodiment of the present invention;

[0044] Figure 4 is a structural schematic diagram of another pixel circuit provided by an embodiment of the present invention;

[0045] Figure 5 is a structural schematic diagram of another pixel circuit provided by an embodiment of the present invention;

[0046] Figure 6 is a driving timing diagram of a pixel circuit provided by an embodiment of the present invention;

[0047] Figure 7 It is a flowchart of a driving method of a pixel circuit provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0048] 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.

[0049] 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, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0050] As described in the background technology, the existing display panel has the problem of uneven display, which affects the display effect of the display panel. The inventor has found that the reasons for the above problems are as follows: the pixel circuit in the display panel includes a driving transistor, and the driving transistor is used to drive the light-emitting device to emit light. Due to the defective state of the gate dielectric, the semiconductor layer and the space between the driving transistor, when different gate voltages are applied to the driving transistor and there is current between the source and the drain of the driving transistor, the defective state will capture different amounts of charge. During the use of the display panel, when the driving transistor passes through different working states, its characteristics will also change due to the different amounts of charge captured by the defective state. Therefore, the state of the driving transistor when driving the previous frame of the display screen will affect the state of driving the current frame of the display screen, causing the current frame of the display screen to have uneven display problems, thereby causing phenomena such as afterimages, which deteriorates the display effect.

[0051] In view of the above problems, an embodiment of the present invention provides a pixel circuit. Figure 1 is a schematic diagram of a pixel circuit provided by an embodiment of the present invention. Figure 1 The pixel circuit includes: a driving module 10, a first light emitting control module 20, a light emitting module 30 and a first initialization module 40.

[0052] The first light-emitting control module 20 is connected between the first power line ELVDD and the first end of the driving module 10. The light-emitting module 30 is connected between the second end of the driving module 10 and the second power line ELVSS. The driving module 10 is used to generate a driving current according to the voltage of its control terminal G to drive the light-emitting module 30 to emit light. The first initialization module 40 is connected to the first initialization signal line Vref1, the control terminal G of the driving module 10 and the second end of the driving module 10. The first light-emitting control module 20 and the first initialization module 40 are used to be turned on in the initialization stage, so that the initialization voltage transmitted by the first initialization signal line Vref1 is written to the control terminal G of the driving module 10 through the first initialization module 40, thereby controlling the driving module 10 to be turned on, and forming a current path from the first power line ELVDD to the first initialization signal line Vref1 through the first light-emitting control module 20, the driving module 10 and the first initialization module 40 in sequence.

[0053] The first power line VDD is connected to a first power voltage, the second power line VSS is connected to a second power voltage, the first power voltage is greater than the second power voltage, the first power voltage may be greater than 0 V, and the second power voltage may be less than or equal to 0 V. The first initialization signal line Vref1 is used to transmit a first initialization voltage, and the first initialization voltage is less than the first power voltage.

[0054] Specifically, the working process of the pixel circuit in a display frame at least includes an initialization stage, a data writing stage and a light emitting stage. In the initialization stage, the first light emitting control module 20 and the first initialization module 40 are controlled to be turned on, and the first initialization voltage transmitted by the first initialization signal line Vref1 can be written into the control terminal G of the driving module 10 through the first initialization module 40 to reset the voltage of the control terminal G of the driving module 10 to the first initialization voltage, and control the driving module 10 to be turned on. Since the first light-emitting control module 20, the driving module 10 and the first initialization module 40 are all turned on, the first power line ELVDD, the first light-emitting control module 20, the driving module 10, the first initialization module 40 and the first initialization signal line Vref1 form a conductive path, so that a current is generated between the first power line ELVDD and the first initialization signal line Vref1, and the current flows through the first light-emitting control module 20, the driving module 10 and the first initialization module 40 in sequence, that is, in the initialization stage, a current passes between the first end and the second end of the driving module 10, thereby resetting the voltage of the first end and the second end of the driving module 10, so that the amount of charge captured by the driving module 10 changes, that is, the amount of charge captured by the driving module 10 is reset. Therefore, in the initialization stage, the control terminal voltage of the driving module 10 and the amount of charge captured by the driving module 10 are reset. At the same time, in order to prevent the light-emitting module 30 from emitting light in the initialization stage, the first initialization voltage transmitted by the first initialization signal line Vref1 can be set so that the magnitude of the first initialization voltage will not cause the light-emitting module 30 to emit light. In the data writing stage, the first light emitting control module 20 is controlled to be turned off, and the data voltage is written to the control terminal G of the driving module 10. In the light emitting stage, the first light emitting control module 20 is controlled to be turned on, so that a conductive path is formed between the first power line ELVDD and the second power line ELVSS, and the driving module 10 can generate a driving current according to the voltage of its own control terminal G, thereby driving the light emitting module 30 to emit light with a corresponding brightness.

[0055] At the end of the last display frame of the display panel, the voltages of the control terminals G of the driving modules 10 in different pixel circuits are different, and the amount of charge captured by the driving modules 10 is different, so that the states of the driving modules 10 in different pixel circuits are also different. After the display panel switches from the last display frame to the current display frame, in the initialization stage of the current display frame, by resetting the voltage of the control terminal of the driving module 10 in each pixel circuit and the amount of charge captured by the driving module 10, the voltage of the control terminal G of the driving module 10 is reset to the first initialization voltage, and the amount of charge captured by the driving module 10 is reset to the same amount of charge, so that the driving modules 10 in each pixel circuit are in the same state, so that the characteristics of the driving modules 10 in each pixel circuit tend to be consistent. In this way, in the light-emitting stage of the current display frame, the state of the driving module 10 in each pixel circuit will not be affected by the last display frame, which helps to improve the display uniformity of the display screen.

[0056] In summary, the technical solution of the embodiment of the present invention, in the initialization stage, controls the first light-emitting control module and the first initialization module to be turned on, so that the initialization voltage transmitted by the first initialization signal line is written into the control end of the driving module through the first initialization module, the control end voltage of the driving module is reset, and the driving module is controlled to be turned on to form a current path from the first power line to the first light-emitting control module, the driving module and the first initialization module to the first initialization signal line in sequence, so that current passes through the driving module, thereby resetting the voltage of the first end and the second end of the driving module, and then resetting the amount of charge captured by the driving module. The advantage of such a setting is that in the initialization stage of each display frame, the control end voltage of the driving module and the amount of charge captured by the driving module can be reset, so that the driving modules in each pixel circuit are in the same state, so that the characteristics of the driving modules in each pixel circuit tend to be consistent, which helps to avoid the state of the driving module in the current display frame being affected by the previous display frame, thereby improving the display uniformity of the display screen and improving the display effect.

[0057] In addition, compared with the prior art, the pixel circuit provided in the embodiment of the present invention includes a driving module, a first light-emitting control module, a light-emitting module and a first initialization module, so that the overall structure of the pixel circuit is simple, which helps to improve the aperture ratio of the display panel. In the initialization stage, by controlling the first light-emitting control module, the driving module and the first initialization module to be turned on, a current path that flows through the first light-emitting control module, the driving module and the first initialization module in sequence can be formed between the first power line and the first initialization signal line, so that the number of modules passed by the current path is small, which helps to improve the reset effect of the driving module, thereby further improving the display uniformity.

[0058] Continue to see Figure 1Optionally, the pixel circuit further includes a data writing module 50 and a storage module 60. The data writing module 50 is connected between the data line Data and the driving module 10, and is used to write the data voltage transmitted by the data line Data into the driving module 10. The storage module 60 is connected to the control terminal G of the driving module 10, and is used to store the voltage of the control terminal G of the driving module 10.

[0059] In this embodiment, the first end of the data writing module 50 can be connected to the data line Data, and the second end of the data writing module 50 can be connected to the control end G of the driving module 10. The first end of the storage module 60 is connected to the control end G of the driving module 10, and the second end of the storage module 60 is connected to a fixed voltage, which can be any fixed voltage. For example, the second end of the storage module 60 can be connected to the first power line ELVDD, so that the second end of the storage module 60 is connected to the first power supply voltage. In the data writing stage, the first light control module 20 can be controlled to be turned off, and the data writing module 50 can be controlled to be turned on, so that the data voltage transmitted by the data line Data can be written to the control end G of the driving module 10 through the data writing module 50, and the voltage of the control end G of the driving module 10 is stored through the storage module 60, so that the driving module 10 drives the light emitting module 30 to emit light with corresponding brightness according to the voltage stored in the storage module 60 during the light emitting stage.

[0060] Figure 2 is a schematic diagram of the structure of another pixel circuit provided by an embodiment of the present invention. Figure 2 On the basis of the above embodiment, optionally, the pixel circuit further includes a second light emitting control module 70. The second light emitting control module 70 is connected between the second end of the driving module 10 and the light emitting module 30, and the second light emitting control module 70 is used to connect the driving module 10 and the light emitting module 30, or disconnect the connection between the driving module 10 and the light emitting module 30.

[0061] Further, the pixel circuit may also include a second initialization module 80, which is connected between the second initialization signal line Vref2 and the first end of the light emitting module 30, and is used to write the signal transmitted by the second initialization signal line Vref2 to the first end of the light emitting module 30 to initialize the voltage of the first end of the light emitting module 30. In this embodiment, the first initialization module 40 is connected to the first initialization signal line Vref1, and the second initialization module 80 is connected to the second initialization signal line Vref2. The second initialization signal line Vref2 is used to transmit the second initialization voltage. The voltages transmitted by the first initialization signal line Vref1 and the second initialization signal line Vref2 may be the same, or may be different. In other embodiments, the first initialization module 40 and the second initialization module 80 may also be connected to the same initialization signal line.

[0062] Further, the control end of the first light-emitting control module 20 may be connected to the first light-emitting control signal line EM1, and the control end of the second light-emitting control module 70 may be connected to the second light-emitting control signal line EM2. The first light-emitting control signal line EM1 is configured to input an on-level signal in the initialization stage, and the second light-emitting control signal line EM2 is configured to input an off-level signal in the initialization stage, so as to control the first light-emitting control module 20 to be on in the initialization stage, and the second light-emitting control module 70 to be off in the initialization stage.

[0063] Specifically, one of the on-level signal and the off-level signal may be a high-level signal, and the other may be a low-level signal. The on-level signal is used to control the corresponding module (including the first light-emitting control module 20 and the second light-emitting control module 70) to be turned on, and the off-level signal is used to control the corresponding module to be turned off. In the initialization stage, the on-level signal is supplied to the first light-emitting control signal line EM1 to control the first light-emitting control module 20 to be turned on, so that the first light-emitting control module 20, the driving module 10 and the second initialization unit 420 form a conductive path to reset the amount of charge captured by the driving module 10. At the same time, the off-level signal is supplied to the second light-emitting control signal line EM2 to control the second light-emitting control module 70 to be turned off, thereby preventing the light-emitting module 30 from emitting light. In the data writing stage, the off-level signal is supplied to the first light-emitting control signal line EM1 and the second light-emitting control signal line EM2 to control the first light-emitting control module 20 and the second light-emitting control module 70 to be turned off, thereby preventing the light-emitting module 30 from emitting light. In the light-emitting stage, a conduction level signal is supplied to the first light-emitting control signal line EM1 and the second light-emitting control signal line EM2, so that a conductive path is formed between the first power line ELVDD and the second power line ELVSS, thereby driving the light-emitting module 30 to emit light through the driving module 10. In the display panel, a light-emitting control signal generating circuit connected to the first light-emitting control signal line EM1 and a light-emitting control signal generating circuit connected to the second light-emitting control signal line EM2 can be respectively provided, so that control signals are supplied to the first light-emitting control signal line EM1 and the second light-emitting control signal line EM2 through different light-emitting control signal generating circuits, thereby respectively controlling the conduction and disconnection of the first light-emitting control module 20 and the second light-emitting control module 70.

[0064] Continue to see Figure 2Optionally, the first initialization module includes a first initialization unit 410 and a second initialization unit 420. The control end of the first initialization unit 410 is connected to the first scan line Scan1, the first initialization unit 410 is connected between the first initialization signal line Vref1 and the control end G of the driving module 10, and the first initialization unit 410 is used to respond to the signal transmitted by the first scan line Scan1 and turn on in the initialization stage to write the initialization voltage transmitted by the first initialization signal line Vref1 into the control end G of the driving module 10, thereby controlling the driving module 10 to turn on. The control end of the second initialization unit 420 is connected to the first scan line Scan1, the second initialization unit 420 is connected between the first initialization signal line Vref1 and the second end of the driving module 10, and the second initialization unit 420 is used to respond to the signal transmitted by the first scan line Scan1 and turn on in the initialization stage to form a current path from the first power line ELVDD to the first initialization signal line Vref1 in sequence through the first light emitting control module 20, the driving module 10 and the second initialization unit 420.

[0065] Specifically, in the initialization stage, a conduction level signal can be supplied to the first scan line Scan1, that is, a signal for controlling the conduction of the first initialization unit 410 and the second initialization unit 420, so that the first initialization voltage transmitted by the first initialization signal line Vref1 is written into the control terminal G of the driving module 10 through the first initialization unit 410, thereby resetting the voltage of the control terminal G of the driving module 10, and controlling the driving module 10 to be turned on, so that the first light-emitting control module 20, the driving module 10 and the second initialization unit 420 form a conductive path, thereby generating a current between the first power line ELVDD and the first initialization signal line Vref1 that flows through the first light-emitting control module 20, the driving module 10 and the second initialization unit 420 in sequence, so that current flows through the driving module 10, thereby resetting the amount of charge captured by the driving module 10.

[0066] The technical solution of this embodiment is to set the first initialization unit 410 and the second initialization unit 420 to be connected to the first scan line Scan1, so that the first initialization unit 410 and the second initialization unit 420 are controlled by the same signal, and there is no need to set corresponding control signal generation circuits in the display panel for the first initialization unit 410 and the second initialization unit 420, which is conducive to simplifying the control method of the pixel circuit and simplifying the structure of the display panel. In the initialization stage, by controlling the first light-emitting control module 20, the driving module 10 and the second initialization unit 420 to be turned on, a current can be generated between the first power line ELVDD and the first initialization signal line Vref1, which flows through the first light-emitting control module 20, the driving module 10 and the second initialization unit 420 in sequence, so that the number of modules passed by the current path is small, which helps to improve the reset effect of the driving module 10, thereby further improving the display uniformity.

[0067] The above embodiment is only described by taking the first initialization unit 410 and the second initialization unit 420 as examples in which both are connected to the first scan line Scan1, controlled by the same signal, and both are connected to the first initialization signal line Vref1. In other embodiments, the first initialization unit 410 and the second initialization unit 420 may be connected to different scan lines, controlled by different signals, and connected to different initialization signal lines. In the case where the first initialization unit 410 and the second initialization unit 420 are connected to different initialization signal lines, the voltages transmitted by the initialization signal lines connected to the first initialization unit 410 and the second initialization unit 420 may be the same, or may be different, so as to set corresponding voltages for resetting the control terminal voltage of the driving module 10 and resetting the amount of charge captured by the driving module 10, respectively.

[0068] Figure 3 is a schematic diagram of the structure of another pixel circuit provided by an embodiment of the present invention. Figure 3 , further, the first initialization unit 410 includes a first transistor T1, and the second initialization unit 420 includes a second transistor T2. The gate of the first transistor T1 is connected to the first scan line Scan1, the first electrode of the first transistor T1 is connected to the first initialization signal line Vref1, and the second electrode of the first transistor T1 is connected to the control terminal G of the driving module 10. The gate of the second transistor T2 is connected to the first scan line Scan1, the first electrode of the second transistor T2 is connected to the first initialization signal line Vref1, and the second electrode of the second transistor T2 is connected to the second end of the driving module 10.

[0069] The first transistor T1 and the second transistor T2 can be either a P-type transistor or an N-type transistor. In this embodiment, the second transistor T2 can be set to be an indium gallium zinc oxide (IGZO) transistor, and the IGZO transistor has the function of reducing leakage current. In the data writing stage and the light emitting stage, the second transistor T2 is controlled to be turned off. By setting the second transistor T2 to be an IGZO transistor, the leakage current of the second transistor T2 can be suppressed, which helps to avoid the second end of the driving module 10 from leaking to the first initialization signal line Vref1 through the second transistor T2 and affecting the stability of the current at the second end of the driving module 10, thereby avoiding the state of the driving module 10 from being affected by the leakage current.

[0070] Optionally, the first transistor T1 is an IGZO transistor. In the data writing stage and the light emitting stage, the first transistor T1 is controlled to be turned off. By setting the first transistor T1 to be an IGZO transistor, the leakage current of the first transistor T1 can be suppressed, which helps to prevent the control terminal G of the driving module 10 from leaking to the first initialization signal line Vref1 through the first transistor T1, thereby improving the stability of the control terminal voltage of the driving module 10 and helping to ensure the display effect. In addition, by setting the first transistor T1 and the second transistor T2 to be IGZO transistors, the first transistor T1 and the second transistor T2 can be controlled by the same scan signal, so that the gates of the first transistor T1 and the second transistor T2 can be connected to the same scan line, thereby simplifying the structure of the display panel.

[0071] Continue to see Figure 3On the basis of the above embodiments, optionally, the data writing module 50 includes a third transistor T3, the gate of the third transistor T3 is connected to the second scan line Scan2, and the third transistor T3 is connected between the data line Data and the driving module 10. In this embodiment, the first electrode of the third transistor T3 can be connected to the data line Data, and the second electrode of the third transistor T3 is connected to the control terminal G of the driving module 10, so that the data voltage transmitted by the data line Data is directly written to the control terminal G of the driving module 10 through the third transistor T3. The storage module 60 includes a storage capacitor Cst, the first electrode of the storage capacitor Cst is connected to a fixed voltage, for example, the first electrode of the storage capacitor Cst can be connected to the first power line ELVDD, so that the first electrode of the storage capacitor Cst is connected to the first power supply voltage, and the second electrode of the storage capacitor Cst is connected to the control terminal G of the driving module 10. The second light-emitting control module 70 includes a fourth transistor T4, the gate of the fourth transistor T4 is connected to the second light-emitting control signal line EM2, the first electrode of the fourth transistor T4 is connected to the second terminal of the driving module 10, and the second electrode of the fourth transistor T4 is connected to the first terminal of the light-emitting module 30. The second initialization module 80 includes a fifth transistor T5 , a gate of the fifth transistor T5 is connected to the third scan line Scan3 , a first electrode of the fifth transistor T5 is connected to the second initialization signal line Vref2 , and a second electrode of the fifth transistor T5 is connected to the first end of the light emitting module 30 .

[0072] Figure 4 is a schematic diagram of the structure of another pixel circuit provided by an embodiment of the present invention. Figure 4 Optionally, in another embodiment, the pixel circuit further includes a threshold compensation module 90, a first end of the data writing module 50 is connected to the data line Data, a second end of the data writing module 50 is connected to a first end of the driving module 10, and the threshold compensation module 90 is connected between the second end of the driving module 10 and the control end G of the driving module 10, and the threshold compensation module 90 is used to compensate for the threshold voltage of the driving module 10.

[0073] Specifically, in the data writing stage, the data writing module 50 and the threshold compensation module 90 are controlled to be turned on, so that the data voltage on the data line Data can be written to the control terminal G of the driving module 10 through the data writing module 50, the driving module 10 and the threshold compensation module 90 in sequence, so that the voltage of the control terminal G of the driving module 10 is related to both the data voltage and the threshold voltage of the driving module 10. At the same time, the voltage of the control terminal G of the driving module 10 is stored by the storage module 60. In the light-emitting stage, the driving module 10 generates a driving current according to the voltage of its own control terminal G, thereby driving the light-emitting module 30 to emit light with a corresponding brightness. Since the voltage of the control terminal G of the driving module 10 is related to both the data voltage and the threshold voltage of the driving module 10, it is helpful to reduce the influence of the threshold voltage of the driving module 10 on the driving current, thereby realizing the threshold voltage compensation of the driving module 10, which helps to improve the display uniformity.

[0074] Figure 5 is a schematic diagram of the structure of another pixel circuit provided by an embodiment of the present invention. Figure 5 On the basis of the above embodiment, a threshold compensation module 90 can be set to include a sixth transistor T6, a first electrode of the third transistor T3 is connected to the data line Data, a second electrode of the third transistor T3 is connected to the first end of the driving module 10, a gate of the sixth transistor T6 is connected to the fourth scan line Scan4, a first electrode of the sixth transistor T6 is connected to the second end of the driving module 10, and a second electrode of the sixth transistor T6 is connected to the control end G of the driving module 10.

[0075] The sixth transistor T6 may be a P-type transistor or an N-type transistor. Optionally, the sixth transistor T6 is an IGZO transistor. In the light-emitting stage, the sixth transistor T6 is controlled to be turned off. By setting the sixth transistor T6 as an IGZO transistor, the leakage current of the sixth transistor T6 can be suppressed, which helps to prevent the control terminal G of the driving module 10 from leaking through the sixth transistor T6, thereby improving the stability of the control terminal voltage of the driving module 10 and helping to ensure the display effect. Figure 5 The case where the sixth transistor T6 and the third transistor T3 are of different types is shown. When the sixth transistor T6 and the third transistor T3 are of different types, the third transistor T3 and the sixth transistor T6 can be respectively connected to different scan lines to control the third transistor T3 and the sixth transistor T6 through different scan signals. In other embodiments, if the sixth transistor T6 and the third transistor T3 are of the same type, the third transistor T3 and the sixth transistor T6 can also be connected to the same scan line to control the conduction and disconnection of the sixth transistor T6 and the third transistor T3 through the same scan signal.

[0076] Continue to see Figure 5On the basis of the above embodiments, the driving module 10 includes a driving transistor DT, the first light-emitting module 30 includes a seventh transistor T7, and the light-emitting module 30 includes a light-emitting device D1. The gate of the seventh transistor T7 is connected to the first light-emitting control signal line EM1, the first electrode of the seventh transistor T7 is connected to the first power line ELVDD, the second electrode of the seventh transistor T7 is connected to the first electrode of the driving transistor DT, and the light-emitting device D1 is connected between the second electrode of the driving transistor DT and the second power line ELVSS. The light-emitting device D1 includes an organic light-emitting diode (OLED) and a micron-level light-emitting diode (Micro-LED).

[0077] Figure 6 It is a driving timing diagram of a pixel circuit provided by an embodiment of the present invention. Figure 6 The drive timing shown is applicable to drive Figures 1 to 5 The pixel circuit shown in the figure works. Figure 5 and Figure 6 , the working principle of the pixel circuit provided by the embodiment of the present invention is described. Exemplarily, the working process of the pixel circuit in a display frame at least includes an initialization phase t1, a data writing phase t2 and a light emitting phase t3. At the end of the n-1th display frame, the gate voltage of the driving transistor DT is V(n-1), and the amount of charge captured by the driving transistor DT is Q(n-1). After the end of the n-1th display frame, the nth display frame is entered.

[0078] In the initialization phase t1 of the nth display frame, the first scan line Scan1, the second scan line Scan2, the third scan line Scan3 and the second light-emitting control signal line EM2 input high-level signals, and the fourth scan line Scan4 and the first light-emitting control signal line EM1 input low-level signals. The first transistor T1, the second transistor T2 and the seventh transistor T7 are turned on, and the third transistor T3 to the sixth transistor T6 are turned off. The first initialization voltage V1 transmitted by the first initialization signal line Vref1 is written into the gate of the driving transistor DT through the third transistor T3, the gate voltage of the driving transistor DT is reset to V1, and the driving transistor DT is controlled to be turned on. A current path is formed between the first power line ELVDD and the first initialization signal line Vref1, which flows through the seventh transistor T7, the driving transistor DT and the second transistor T2 in sequence, so that current flows through the driving transistor DT, thereby resetting the voltage of the first and second electrodes (i.e., the source and the drain) of the driving transistor DT, so that the amount of charge captured by the driving transistor DT is reset from Q(n-1) to Q1, so as to avoid the state of the driving transistor DT in the nth display frame being affected by the n-1th display frame.

[0079] In the data writing phase t2 of the nth display frame, the first scan line Scan1, the second scan line Scan2, and the third scan line Scan3 input low-level signals, and the fourth scan line Scan4, the first light-emitting control signal line EM1 and the second light-emitting control signal line EM2 input high-level signals. The third transistor T3, the fifth transistor T5, and the sixth transistor T6 are turned on, and the first transistor T1, the second transistor T2, the fourth transistor T4, and the seventh transistor T7 are turned off. The data voltage transmitted by the data line Data is sequentially written into the gate of the driving transistor DT through the third transistor T3, the driving transistor DT, and the sixth transistor T6, so that the gate voltage of the driving transistor DT is related to the data voltage and the threshold voltage of the driving transistor DT, and the gate voltage of the driving transistor DT is stored through the storage capacitor Cst. The second initialization voltage on the second initialization signal line Vref2 is written into the first electrode of the light-emitting device D1 through the fifth transistor T5 to prevent the light-emitting device D1 from emitting light.

[0080] In the light-emitting stage t3 of the nth display frame, the first scan line Scan1, the fourth scan line Scan4, the first light-emitting control signal line EM1 and the second light-emitting control signal line EM2 input low-level signals, and the second scan line Scan2 and the third scan line Scan3 input high-level signals. The fourth transistor T4, the seventh transistor T7 and the driving transistor DT are turned on, and the remaining transistors are turned off. The driving transistor DT generates a driving current according to its own gate voltage, thereby driving the light-emitting device D1 to emit light with a corresponding brightness. In the light-emitting stage t3, since the gate voltage of the driving transistor DT is related to the data voltage and the threshold voltage of the driving transistor DT, it helps to compensate for the influence of the threshold voltage of the driving transistor DT on the driving current, thereby improving the display uniformity of the light-emitting stage.

[0081] In the initialization stage t1 of the nth display frame, since the gate voltage of the driving transistor DT in each pixel circuit is reset to V1, the amount of charge captured by the driving transistor DT in each pixel circuit is reset to Q1, so that the driving transistor DT in each pixel circuit is in the same state, thereby making the characteristics of the driving transistor DT in each pixel circuit tend to be consistent. In this way, in the light-emitting stage t3 of the nth display frame, the state of the driving transistor DT in each pixel circuit will not be affected by the n-1th display frame, thereby further improving the display uniformity of the display screen.

[0082] The embodiment of the present invention further provides a display panel, which includes the pixel circuit in any of the above embodiments, and the display panel may be an organic light emitting diode (OLED) display panel, an active matrix organic light emitting diode (AMOLED) display panel, a micron-level light emitting diode Micro-LED display panel, etc. The display panel provided by the embodiment of the present invention includes the pixel circuit in any of the above embodiments, and thus has the corresponding functional modules and beneficial effects of the pixel circuit, which will not be described in detail here.

[0083] An embodiment of the present invention further provides a method for driving a pixel circuit. The method is suitable for driving the pixel circuit in any of the above embodiments. Figure 7 is a flowchart of a driving method of a pixel circuit provided by an embodiment of the present invention. Figure 7 , the driving method of the pixel circuit specifically includes the following steps:

[0084] S110. In the initialization stage, the first light-emitting control module and the first initialization module are controlled to be turned on, so as to write the initialization voltage transmitted by the first initialization signal line to the control end of the driving module through the first initialization module, thereby controlling the driving module to be turned on, and forming a current path from the first power line through the first light-emitting control module, the driving module and the first initialization module to the first initialization signal line in sequence.

[0085] S120 , in the data writing phase, writing a data voltage to the control terminal of the driving module.

[0086] S130, in the light-emitting stage, controlling the first light-emitting control module to be turned on, so that the driving module generates a driving current according to the voltage of its own control terminal, thereby driving the light-emitting module to emit light.

[0087] The technical solution of the embodiment of the present invention is to control the first light-emitting control module and the first initialization module to be turned on during the initialization stage, so that the initialization voltage transmitted by the first initialization signal line is written into the control end of the driving module through the first initialization module, and the control end voltage of the driving module is reset, and the driving module is controlled to be turned on to form a current path from the first power line to the first light-emitting control module, the driving module and the first initialization module to the first initialization signal line in sequence, so that current passes through the driving module, thereby resetting the voltage of the first end and the second end of the driving module, and further resetting the amount of charge captured by the driving module. The advantage of such a setting is that during the initialization stage of each display frame, the control end voltage of the driving module and the amount of charge captured by the driving module can be reset, so that the driving modules in each pixel circuit are in the same state, so that the characteristics of the driving modules in each pixel circuit tend to be consistent, which helps to avoid the state of the driving module in the current display frame being affected by the previous display frame, thereby improving the display uniformity of the display screen and improving the display effect.

[0088] In addition, during the initialization stage, by controlling the first light-emitting control module, the driving module and the first initialization module to be turned on, a current path can be formed between the first power line and the first initialization signal line, which flows through the first light-emitting control module, the driving module and the first initialization module in sequence. This makes it possible to reduce the number of modules passed by the current path, thereby helping to improve the reset effect of the driving module, thereby further improving display uniformity.

[0089] On the basis of the above embodiment, optionally, the first initialization module includes a first initialization unit and a second initialization unit; the control end of the first initialization unit is connected to the first scan line, and the first initialization unit is connected between the first initialization signal line and the control end of the driving module; the control end of the second initialization unit is connected to the first scan line, and the second initialization unit is connected between the first initialization signal line and the second end of the driving module. Accordingly, step S110 specifically includes:

[0090] During the initialization stage, a conduction level signal is supplied to the first scan line to control the conduction of the first initialization unit and the second initialization unit. The initialization voltage transmitted by the first initialization signal line is written into the control end of the driving module through the first initialization unit, thereby controlling the conduction of the driving module and forming a current path from the first power line through the first light-emitting control module, the driving module and the second initialization unit to the first initialization signal line.

[0091] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the present invention can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of the present invention can be achieved, and this document does not limit this.

[0092] 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 first light-emitting control module and a light-emitting module, wherein the first light-emitting control module is connected between a first power line and a first end of the driving module, the light-emitting module is connected between a second end of the driving module and a second power line, and the driving module is used to generate a driving current according to a voltage at its control end to drive the light-emitting module to emit light; a first initialization module, connected to a first initialization signal line, a control end of the driving module and a second end of the driving module, wherein the first light-emitting control module and the first initialization module are used to be turned on in an initialization phase, so that an initialization voltage transmitted by the first initialization signal line is written to the control end of the driving module through the first initialization module, thereby controlling the driving module to be turned on, and forming a current path from the first power line to the first initialization signal line via the first light-emitting control module, the driving module and the first initialization module in sequence; The first initialization module includes a first initialization unit and a second initialization unit; The control end of the first initialization unit is connected to the first scan line, the first initialization unit is connected between the first initialization signal line and the control end of the driving module, and the first initialization unit is used to respond to the signal transmitted by the first scan line and turn on in the initialization stage to write the initialization voltage transmitted by the first initialization signal line into the control end of the driving module, thereby controlling the driving module to turn on; The control end of the second initialization unit is connected to the first scan line, the second initialization unit is connected between the first initialization signal line and the second end of the driving module, and the second initialization unit is used to respond to the signal transmitted by the first scan line and be turned on during the initialization stage to form a current path from the first power line to the first initialization signal line via the first light-emitting control module, the driving module and the second initialization unit in sequence.

2. The pixel circuit according to claim 1, characterized in that: The first initialization unit includes a first transistor, and the second initialization unit includes a second transistor; The gate of the first transistor is connected to the first scan line, the first electrode of the first transistor is connected to the first initialization signal line, and the second electrode of the first transistor is connected to the control end of the driving module; A gate of the second transistor is connected to the first scan line, a first electrode of the second transistor is connected to the first initialization signal line, and a second electrode of the second transistor is connected to the second end of the driving module.

3. The pixel circuit according to claim 2, characterized in that: The second transistor includes an indium gallium zinc oxide transistor.

4. The pixel circuit according to claim 1, characterized in that: The pixel circuit further includes: a second light-emitting control module connected between the second end of the driving module and the light-emitting module, and used to connect the driving module and the light-emitting module, or disconnect the driving module and the light-emitting module; The control end of the first light-emitting control module is connected to the first light-emitting control signal line, and the control end of the second light-emitting control module is connected to the second light-emitting control signal line; The first light-emitting control signal line is configured to input a conduction level signal in the initialization stage, and the second light-emitting control signal line is configured to input a cutoff level signal in the initialization stage to control the first light-emitting control module to be turned on in the initialization stage, and the second light-emitting control module to be turned off in the initialization stage.

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

6. The pixel circuit according to claim 1, characterized in that: The pixel circuit also includes a data writing module, a storage module and a second initialization module; The data writing module is connected between the data line and the driving module, and is used to write the data voltage transmitted by the data line into the driving module; The storage module is connected to the control end of the driving module, and the storage module is used to store the voltage of the control end of the driving module; The second initialization module is connected between the second initialization signal line and the first end of the light emitting module, and is used for writing a signal transmitted by the second initialization signal line into the first end of the light emitting module.

7. The pixel circuit according to claim 6, characterized in that: The pixel circuit also includes a threshold compensation module. The data writing module is connected to the first end of the driving module. The threshold compensation module is connected between the second end of the driving module and the control end of the driving module. The threshold compensation module is used to compensate for the threshold voltage of the driving module.

8. The pixel circuit according to claim 7, characterized in that: The data writing module comprises a third transistor, the gate of the third transistor is connected to the second scanning line, and the third transistor is connected between the data line and the driving module; The storage module comprises a storage capacitor, a first electrode of the storage capacitor is connected to a fixed voltage, and a second electrode of the storage capacitor is connected to a control terminal of the driving module; The second initialization module includes a fifth transistor, a gate of the fifth transistor is connected to the third scan line, a first electrode of the fifth transistor is connected to the second initialization signal line, and a second electrode of the fifth transistor is connected to the first end of the light emitting module; The threshold compensation module includes a sixth transistor, a first electrode of the third transistor is connected to the data line, a second electrode of the third transistor is connected to the first end of the driving module, a gate of the sixth transistor is connected to a fourth scan line, a first electrode of the sixth transistor is connected to the second end of the driving module, and a second electrode of the sixth transistor is connected to the control end of the driving module.

9. The pixel circuit according to any one of claims 1 to 8, characterized in that: The driving module includes a driving transistor, the first light emitting control module includes a seventh transistor, and the light emitting module includes a light emitting device; The gate of the seventh transistor is connected to the first light-emitting control signal line, the first electrode of the seventh transistor is connected to the first power line, the second electrode of the seventh transistor is connected to the first electrode of the driving transistor, and the light-emitting device is connected between the second electrode of the driving transistor and the second power line.

10. A method for driving a pixel circuit, characterized in that: The pixel circuit comprises: a driving module, a first light-emitting control module, a light-emitting module and a first initialization module; the first light-emitting control module is connected between a first power line and a first end of the driving module, the light-emitting module is connected between a second end of the driving module and a second power line, the driving module is used to generate a driving current according to a voltage at its control end to drive the light-emitting module to emit light; the first initialization module is connected to a first initialization signal line, a control end of the driving module and a second end of the driving module; The driving method of the pixel circuit includes: In the initialization stage, the first light-emitting control module and the first initialization module are controlled to be turned on, so that the initialization voltage transmitted by the first initialization signal line is written to the control end of the driving module through the first initialization module, thereby controlling the driving module to be turned on, and forming a current path from the first power line to the first initialization signal line via the first light-emitting control module, the driving module and the first initialization module in sequence; The first initialization module includes a first initialization unit and a second initialization unit; the control end of the first initialization unit is connected to the first scan line, and the first initialization unit is connected between the first initialization signal line and the control end of the driving module; the control end of the second initialization unit is connected to the first scan line, and the second initialization unit is connected between the first initialization signal line and the second end of the driving module; In the initialization stage, the first light-emitting control module and the first initialization module are controlled to be turned on, so that the initialization voltage transmitted by the first initialization signal line is written to the control end of the driving module through the first initialization module, thereby controlling the driving module to be turned on, and forming a current path from the first power line to the first initialization signal line via the first light-emitting control module, the driving module and the first initialization module in sequence, including: During the initialization stage, a conduction level signal is supplied to the first scan line to control the conduction of the first initialization unit and the second initialization unit, and the initialization voltage transmitted by the first initialization signal line is written into the control end of the driving module through the first initialization unit, thereby controlling the conduction of the driving module and forming a current path from the first power line to the first initialization signal line via the first light-emitting control module, the driving module and the second initialization unit in sequence.

11. A display panel, characterized in that: The invention comprises the pixel circuit described in any one of claims 1 to 9.

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