Display device

Abstract

This application relates to a display device including a pixel circuit. The pixel circuit comprises a driving transistor, a brightness control circuit, a light emission duration control circuit, and a switching circuit. The driving transistor drives a light-emitting device to emit light. The brightness control circuit outputs a brightness control signal based on an input amplitude modulation signal. The switching circuit is connected between the driving transistor and the brightness control circuit and is controlled by the light emission duration control circuit. The light emission duration control circuit outputs a duration control signal based on an input data voltage signal, a ramp signal, and a second power supply voltage. The duration control signal has a potential including a first potential and a second potential. The switching circuit is turned on when the duration control signal is at the first potential, causing the driving transistor to drive the light-emitting device to emit light according to the brightness control signal; and turned off when the duration control signal is at the second potential. This pixel circuit can improve the uniformity of display brightness.

Description

Technical Field

[0001] This application relates to the field of display technology, and in particular to a display device. Background Technology

[0002] μLED, or Micro LED (light-emitting diode), has gradually become a commonly used light-emitting device in display devices due to its advantages such as small size, fast response speed, high luminous efficiency, strong stability and long lifespan.

[0003] Currently, the brightness of a μLED is typically controlled by controlling the current flowing through it using PAM (Pulse Amplitude Modulation).

[0004] However, because the IV characteristic curve (current-voltage characteristic drive) of μLED is very steep, that is, the change in voltage between the two poles corresponding to the change from low gray level current to high gray level current is very small, it is difficult to accurately control the display brightness of μLED by the magnitude of μLED current, resulting in poor display uniformity of display device. Summary of the Invention

[0005] Therefore, it is necessary to provide a control method for display devices and pixel circuits that can improve display uniformity.

[0006] In a first aspect, a display device is provided, the display device including a pixel circuit, the pixel circuit comprising:

[0007] A driving transistor, wherein the first terminal of the driving transistor is used to connect to a light-emitting device, and the second terminal of the driving transistor is used to connect to a first power supply voltage;

[0008] A brightness control circuit is provided, wherein the brightness control circuit is used to receive an amplitude modulation signal and output a brightness control signal according to the amplitude modulation signal;

[0009] A light emission duration control circuit is provided, wherein the light emission duration control circuit is used to receive a data voltage signal, a ramp signal, and a second power supply voltage, and outputs a duration control signal according to the data voltage signal, the ramp signal, and the second power supply voltage; the potential of the duration control signal includes a first potential and a second potential;

[0010] A switching circuit, wherein the first terminal of the switching circuit is connected to the brightness control circuit, the second terminal of the switching circuit is connected to the control electrode of the driving transistor, and the control terminal of the switching circuit is connected to the light emission duration control circuit.

[0011] Specifically, when the duration control signal is at the first potential, the switching circuit is turned on so that the driving transistor drives the light-emitting device to emit light according to the brightness control signal; when the duration control signal is at the second potential, the switching circuit is turned off.

[0012] In one embodiment, the amplitude modulation signal is a constant voltage signal, and the voltage of the amplitude modulation signal is positively correlated with the voltage of the brightness control signal.

[0013] In one embodiment, the aspect ratio of the transistor in the brightness control circuit is the same as that of the driving transistor, and the brightness control circuit is used to perform threshold compensation according to the amplitude modulation signal and output the brightness control signal.

[0014] In one embodiment, the brightness control circuit includes a first transistor and a first capacitor; the aspect ratio of the first transistor is the same as that of the driving transistor.

[0015] The first terminal of the first transistor is connected to the control terminal of the first transistor, the first terminal of the switching circuit, and the first terminal of the first capacitor. The second terminal of the first transistor is used to receive the amplitude modulation signal, and the second terminal of the first capacitor is grounded.

[0016] In one embodiment, the light emission duration control circuit includes:

[0017] A pulse width control unit is used to receive the data voltage signal and perform threshold voltage compensation based on the data voltage signal.

[0018] The first light-emitting control unit is connected to the control terminal of the switching circuit and the pulse width control unit; the first light-emitting control unit is used to receive the light-emitting control signal and, under the action of the light-emitting control signal, to connect the control terminal of the switching circuit and the pulse width control unit.

[0019] The second light-emitting control unit is connected to the pulse width control unit; the second light-emitting control unit is used to receive the second power supply voltage and the light-emitting control signal, and is turned on under the action of the light-emitting control signal to transmit the second power supply voltage to the pulse width control unit;

[0020] The pulse width control unit is used to receive the ramp signal and, under the action of the ramp signal, output a duration control signal with the potential of the first potential according to the second power supply voltage.

[0021] In one embodiment, the pulse width control unit includes a second transistor, a third transistor, a fourth transistor, and a second capacitor; the first terminal of the second transistor is connected to the first light-emitting control unit and the first terminal of the third transistor, the second terminal of the third transistor is connected to the control terminal of the second transistor and the first terminal of the second capacitor, and the second terminal of the second capacitor is used to receive the ramp signal; the second terminal of the second transistor is connected to the second light-emitting control unit and the first terminal of the fourth transistor, and the second terminal of the fourth transistor is used to receive the data voltage signal; the control terminals of the third transistor and the fourth transistor are both connected to a write scan signal.

[0022] In one embodiment, the first light-emitting control unit includes a fifth transistor; the first terminal of the fifth transistor is connected to the control terminal of the switching circuit, the second terminal of the fifth transistor is connected to the pulse width control unit, and the control terminal of the fifth transistor is used to receive the light-emitting control signal.

[0023] In one embodiment, the second light-emitting control unit includes a sixth transistor; the first terminal of the sixth transistor is connected to the pulse width control unit, the second terminal of the sixth transistor is used to connect to the second power supply voltage, and the control terminal of the sixth transistor is used to connect to the light-emitting control signal.

[0024] In one embodiment, the pixel circuit includes a seventh transistor; the first terminal of the seventh transistor is connected to the second terminal of the driving transistor, the second terminal of the seventh transistor is used to access the first power supply voltage, and the control terminal of the seventh transistor is used to access the light emission control signal.

[0025] In one embodiment, the switching circuit includes an eighth transistor; the first terminal of the eighth transistor is connected to the brightness control circuit, the second terminal of the eighth transistor is connected to the control terminal of the driving transistor, and the control terminal of the eighth transistor is connected to the light emission duration control circuit.

[0026] In one embodiment, the pixel circuit further includes a reset circuit, which is connected to the brightness control circuit and the light emission duration control circuit respectively; the reset circuit is used to receive a reset scan signal and reset the brightness control circuit and the light emission duration control circuit according to the reset scan signal.

[0027] Secondly, this application provides a method for controlling a pixel circuit, applied to a display device as described above; the method includes:

[0028] Output an amplitude modulation signal so that the brightness control circuit outputs a brightness control signal according to the amplitude modulation signal;

[0029] The output data voltage signal and ramp signal enable the light emission duration control circuit to output a duration control signal based on the data voltage signal, the ramp signal, and the second power supply voltage; the potential of the duration control signal includes a first potential and a second potential.

[0030] Specifically, when the duration control signal is at the first potential, the switching circuit is turned on according to the duration control signal, so that the driving transistor drives the light-emitting device to emit light according to the brightness control signal; when the duration control signal is at the second potential, the switching circuit is turned off according to the duration control signal.

[0031] The control method for the aforementioned display device and pixel circuit includes a pixel circuit comprising a driving transistor, a brightness control circuit, an emission duration control circuit, and a switching circuit. The driving transistor drives a light-emitting device to emit light. The brightness control circuit outputs a brightness control signal based on an input amplitude modulation signal. The switching circuit is connected between the driving transistor and the brightness control circuit and is controlled by the emission duration control circuit. The emission duration control circuit outputs a duration control signal based on an input data voltage signal, a ramp signal, and a second power supply voltage. The duration control signal has a first potential and a second potential. The switching circuit is turned on when the duration control signal is at the first potential, causing the driving transistor to drive the light-emitting device to emit light according to the brightness control signal; it is turned off when the duration control signal is at the second potential. Therefore, by adjusting the duration of the first potential signal output by the emission duration control circuit based on the data voltage signal and the ramp signal, the conduction duration of the switching circuit can be adjusted, thereby controlling the duration for which the driving transistor drives the light-emitting device to emit light. Since the duration of light emission of a light-emitting device is related to the brightness perceived by the human eye, adjusting the brightness and duration of light emission through brightness control circuits, light emission duration control circuits, and switching circuits can make the pixel circuit control the display brightness of the light-emitting device more precise and improve the display uniformity of the display device. Attached Figure Description

[0032] To more clearly illustrate the technical solutions in the embodiments of this application or the conventional technology, the drawings used in the description of the embodiments or the conventional technology will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0033] Figure 1 This is a structural diagram of a pixel circuit according to an embodiment of this application;

[0034] Figure 2 This is a structural diagram of a pixel circuit according to another embodiment of this application;

[0035] Figure 3 This is a structural diagram of the pixel circuit in another embodiment of this application;

[0036] Figure 4 This is a structural diagram of the pixel circuit in another embodiment of this application;

[0037] Figure 5 This is a circuit structure diagram of a pixel circuit in one embodiment of this application;

[0038] Figure 6 This is a signal timing diagram of one embodiment of the present application;

[0039] Figure 7 This is a circuit structure diagram of the pixel circuit during the reset phase in one embodiment of this application;

[0040] Figure 8 This is a circuit structure diagram of the pixel circuit in one state during the data writing and threshold voltage compensation stages in an embodiment of this application;

[0041] Figure 9 This is a circuit structure diagram of the pixel circuit in another state during the data writing and threshold voltage compensation stages in one embodiment of this application.

[0042] Figure 10 This is a circuit structure diagram of a pixel circuit in one state of the light-emitting stage in an embodiment of this application;

[0043] Figure 11 This is a circuit structure diagram of the pixel circuit in another state of the light-emitting stage in one embodiment of this application;

[0044] Figure 12 This is a flowchart illustrating a control method for a pixel circuit in one embodiment of this application;

[0045] Figure 13 This is a flowchart illustrating the control method of the pixel circuit in another embodiment of this application;

[0046] Figure 14 This is a flowchart illustrating the control method of the pixel circuit in another embodiment of this application.

[0047] Figure label:

[0048] 100 - Brightness control circuit, 200 - Light emission duration control circuit, 300 - Switching circuit, 400 - Reset circuit, 210 - Pulse width control unit, 220 - First light emission control unit, 230 - Second light emission control unit, D - Light emission device, T1 - Driving transistor, T2 - First reset transistor, T3 - Second reset transistor, T4 - First transistor, T5 - Fifth transistor, T6 - Sixth transistor, T7 - ​​Seventh transistor, T8 - Second transistor, T9 - Third transistor, T10 - Fourth transistor, T11 - Eighth transistor, C1 - First capacitor, C2 - Second capacitor, S1 - Reset scan signal, S2 - Write scan signal, EM - Light emission control signal, VSS - First power supply voltage, VGH - Second power supply voltage, VDD - Third power supply voltage, GND - Ground, Vint - Initialization voltage signal, Data_PAM - Amplitude modulation signal, Data_PWM - Data voltage signal, Sweep - Ramp signal. Detailed Implementation

[0049] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings, which illustrate embodiments of the present application. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of this application will be thorough and complete.

[0050] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0051] It is understood that the terms "first," "second," etc., used herein may be used to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish one element from another. For example, without departing from the scope of this application, a first resistor may be referred to as a second resistor, and similarly, a second resistor may be referred to as a first resistor. Both the first resistor and the second resistor are resistors, but they are not the same resistor.

[0052] It is understood that the term "connection" in the following embodiments should be understood as "electrical connection," "communication connection," etc., if the connected circuits, modules, units, etc., have electrical signal or data transmission with each other.

[0053] It is understandable that "at least one" refers to one or more, and "multiple" refers to two or more. "At least a part of an element" refers to part or all of an element.

[0054] When used herein, the singular forms of “a,” “an,” and “the” may also include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising / including” or “having,” etc., specify the presence of the stated features, wholes, steps, operations, components, parts, or combinations thereof, but do not preclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof. Meanwhile, the term “and / or” as used in this specification includes any and all combinations of the associated listed items.

[0055] This embodiment provides a display device, which includes a pixel circuit. Please refer to... Figure 1 The pixel circuit includes a driving transistor T1. The first terminal of the driving transistor T1 is used to connect to the light-emitting device D, and the second terminal of the driving transistor T1 is used to connect to the first power supply voltage VSS.

[0056] The driving transistor T1 provides driving current to the light-emitting device D, thereby driving the device D to emit light. The light-emitting device D can be a μLED or other types of light-emitting elements. The connection between the light-emitting device D and the driving transistor T1 can be configured according to specific circumstances. As an example, the cathode of the light-emitting device D is connected to the first terminal of the driving transistor T1, and the anode of the light-emitting device D is connected to the third power supply voltage VDD.

[0057] The pixel circuit also includes a brightness control circuit 100. The brightness control circuit 100 is used to receive the amplitude modulation signal Data_PAM and output a brightness control signal according to the amplitude modulation signal Data_PAM.

[0058] The brightness control signal is applied to the control electrode of the driving transistor T1 to control the magnitude of the driving current generated by the driving transistor T1. The larger the driving current, the greater the brightness of the light-emitting device D.

[0059] The voltage of the brightness control signal is positively correlated with the voltage of the amplitude modulation signal Data_PAM. The voltage of the amplitude modulation signal Data_PAM can be set according to the actual situation. As an example, if a higher brightness is required for the light-emitting device D, the voltage value of the amplitude modulation signal Data_PAM can be increased, resulting in a brightness control signal with a higher voltage. Therefore, by adjusting the voltage of the amplitude modulation signal Data_PAM, the brightness of the emitted light can be controlled.

[0060] The pixel circuit also includes an emission duration control circuit 200. The emission duration control circuit 200 is used to receive the data voltage signal Data_PWM, the ramp signal Sweep, and the second power supply voltage VGH, and to output a duration control signal based on the data voltage signal Data_PWM, the ramp signal Sweep, and the second power supply voltage VGH.

[0061] The data voltage signal Data_PWM is output by the driver chip, and its magnitude is related to the brightness of the image to be displayed. The slope signal Sweep is a voltage signal whose amplitude increases or decreases linearly at a constant rate over time. In some embodiments, the slope voltage signal Sweep can be a triangular wave signal. The voltage of the second power supply voltage VGH can be set according to specific circumstances; its voltage value can be equal to or different from the third power supply voltage VDD.

[0062] The duration control signal has two potentials: a first potential and a second potential. One of the first potential and the second potential is high, and the other is low; the specific value can be determined based on the actual situation. As an example, the first potential is high, and the second potential is low.

[0063] When the voltage of the data voltage signal Data_PWM changes, the light emission duration control circuit 200 will adjust the duration of its output signal (duration control signal) at the first potential according to the data voltage signal Data_PWM and the ramp signal Sweep.

[0064] The pixel circuit also includes a switching circuit 300. The first terminal of the switching circuit 300 is connected to the brightness control circuit 100, the second terminal of the switching circuit 300 is connected to the control electrode of the driving transistor T1, and the control terminal of the switching circuit 300 is connected to the light emission duration control circuit 200.

[0065] When the duration control signal is at the first potential, the switching circuit 300 is turned on so that the driving transistor T1 drives the light-emitting device D to emit light according to the brightness control signal; when the duration control signal is at the second potential, the switching circuit 300 is turned off.

[0066] Specifically, when the duration control signal output by the light-emitting duration control circuit 200 is at the first potential, the switching circuit 300 is turned on and transmits the brightness control signal to the control electrode of the driving transistor T1. The driving transistor T1 generates a driving current according to the brightness control signal, driving the light-emitting device D to emit light. When the duration control signal is at the second potential, the switching circuit 300 is turned off, cutting off the transmission path of the brightness control signal, causing the light-emitting device D to stop emitting light. This allows the light-emitting duration of the light-emitting device D to be adjusted according to the duration of the duration control signal at the first potential. Since the light-emitting duration of the light-emitting device D is related to the brightness perceived by the human eye, the control precision of the display brightness can be improved.

[0067] The aforementioned display device includes a pixel circuit, which comprises a driving transistor T1, a brightness control circuit 100, a light emission duration control circuit 200, and a switching circuit 300. The driving transistor T1 drives the light-emitting device D to emit light. The brightness control circuit 100 outputs a brightness control signal based on an input amplitude modulation signal Data_PAM. The switching circuit 300 is connected between the driving transistor T1 and the brightness control circuit 100 and is controlled by the light emission duration control circuit 200. The light emission duration control circuit 200 outputs a duration control signal based on an input data voltage signal Data_PWM, a ramp signal Sweep, and a second power supply voltage VGH. The duration control signal has a first potential and a second potential, and the duration of the duration control signal at the first potential and the second potential varies according to the data voltage signal Data_PWM. The switching circuit 300 is turned on when the duration control signal is at the first potential, causing the driving transistor T1 to drive the light-emitting device D to emit light according to the brightness control signal; it is turned off when the duration control signal is at the second potential. Therefore, by adjusting the duration of its output signal at the first potential based on the data voltage signal Data_PWM and the slope signal Sweep, the light emission duration of the switching circuit 300 can be adjusted, thereby controlling the duration for which the driving transistor T1 drives the light-emitting device D to emit light. Since the light emission duration of the light-emitting device D is related to the brightness perceived by the human eye, adjusting the brightness and duration of the light-emitting device D through the brightness control circuit 100, the light emission duration control circuit 200, and the switching circuit 300 allows for more precise control of the display brightness of the light-emitting device D by the pixel circuit, improving the display uniformity of the display device.

[0068] In some embodiments, the amplitude modulation signal Data_PAM is a constant voltage signal, and the voltage of the amplitude modulation signal Data_PAM is positively correlated with the voltage of the brightness control signal.

[0069] Since the voltage of the amplitude modulation signal Data_PAM is positively correlated with the voltage of the brightness control signal, and the voltage of the brightness control signal is positively correlated with the magnitude of the driving current, when the amplitude modulation signal Data_PAM is a constant voltage signal, the driving transistor T1 drives the light-emitting device D in a constant current driving mode. This constant current driving mode can improve the uniformity of the emission wavelength of the light-emitting device D, thereby improving the display uniformity of the display device and thus improving the display quality.

[0070] In some embodiments, the aspect ratio of the transistor in the brightness control circuit 100 is the same as that of the driving transistor T1. The brightness control circuit 100 is used to perform threshold compensation based on the amplitude modulation signal Data_PAM and output a brightness control signal.

[0071] In this embodiment, the brightness control circuit 100 performs threshold compensation based on the amplitude modulation signal Data_PAM to obtain a brightness control signal, the voltage of which is the voltage after threshold compensation.

[0072] Since the transistors in the brightness control circuit 100 and the driving transistor T1 have the same width-to-length ratio, their threshold voltages are theoretically the same. Therefore, when the threshold-compensated brightness control signal is applied to the driving transistor T1, threshold voltage compensation of the driving transistor T1 can be achieved, thereby improving display uniformity.

[0073] In practical implementation, the brightness control circuit 100 and the light emission duration control circuit 200 can also be reset according to specific circumstances. In some embodiments, such as Figure 2 As shown, the pixel circuit also includes a reset circuit 400. The reset circuit 400 is connected to the brightness control circuit 100 and the light emission duration control circuit 200, respectively. The reset circuit 400 is used to receive the reset scan signal S1, and under the action of the reset scan signal S1, it resets the brightness control circuit 100 and the light emission duration control circuit 200.

[0074] Specifically, the reset circuit 400 is also used to connect the fourth power supply voltage and the initialization voltage signal, and to reset the brightness control circuit 100 according to the fourth power supply voltage, and to reset the light emission duration control circuit 200 according to the initialization voltage signal.

[0075] The magnitudes of the fourth power supply voltage and the initialization voltage signal are not limited and can be set according to specific needs. Optionally, the fourth power supply voltage can be equal to the third power supply voltage VDD. Furthermore, the reset circuit 400 can be connected to the anode of the light-emitting device D to access the third power supply voltage VDD. This simplifies the circuit structure of the pixel circuit and reduces the number of power supply voltage signal lines.

[0076] When it is necessary to reset the brightness control circuit 100 and the light emission duration control circuit 200, the reset circuit 400 resets the brightness control circuit 100 according to the third power supply voltage VDD under the action of the reset scan signal S1, and resets the light emission duration control circuit 200 according to the initialization voltage signal.

[0077] By resetting the brightness control circuit 100 and the light emission duration control circuit 200, these two circuits can be in a defined initial state before each operation, which helps to avoid display abnormalities caused by residual circuit states, thereby improving the stability of the pixel circuit and the reliability of the display.

[0078] In this embodiment, the reset circuit 400 can simultaneously reset the brightness control circuit 100 and the light emission duration control circuit 200, simplifying the control timing. Furthermore, the simultaneous reset of the brightness control circuit 100 and the light emission duration control circuit 200 reduces the total reset time, allowing sufficient time for subsequent light emission operations. Thus, while ensuring the reset effect, it extends the duration during which the light-emitting device D can emit light, contributing to improved display brightness.

[0079] In some embodiments, the operation of the pixel circuit mainly consists of three stages: a reset stage, a data writing and threshold voltage compensation stage, and a light emission stage. The operation of the pixel circuit is described below based on these three stages.

[0080] During the reset phase, the driver chip outputs a reset scan signal S1 to reset the brightness control circuit 100 and the light emission duration control circuit 200.

[0081] By resetting the brightness control circuit 100 and the light emission duration control circuit 200 to their initial states, any residual circuit states from the previous display stage can be eliminated, thereby preventing these residual states from adversely affecting the current display stage and improving display accuracy.

[0082] During the data writing and threshold voltage compensation stages, the driver chip outputs an amplitude modulation signal Data_PAM, and the brightness control circuit 100 performs threshold compensation based on the amplitude modulation signal Data_PWM and outputs a brightness control signal.

[0083] When the threshold-compensated brightness control signal is applied to the driving transistor T1, threshold voltage compensation of the driving transistor T1 can be achieved, thereby improving display uniformity.

[0084] The driver chip also outputs a data voltage signal Data_PWM. The light emission duration control circuit 200 performs threshold voltage compensation based on the data voltage signal Data_PWM and outputs a duration control signal.

[0085] At this time, the potential of the duration control signal is the second potential, i.e., the invalid potential, so that the switching circuit 300 is in the open state, ensuring that the driving transistor T1 will not drive the light-emitting device D to emit light erroneously.

[0086] During this stage, the data voltage signal Data_PWM is written to the light emission duration control circuit 200, and the light emission duration control circuit 200 performs threshold voltage compensation based on the data voltage signal Data_PWM. The light emission duration control circuit 200 includes a pulse width modulation transistor, and the on or off state of the pulse width modulation transistor affects the output of the duration control signal. Therefore, when the data voltage signal Data_PWM is received, threshold voltage compensation of the pulse width modulation transistor can reduce the influence of the threshold voltage of the pulse width modulation transistor on the potential of the duration control signal.

[0087] During the light-emitting stage, the driver chip outputs a ramp signal Sweep, and the light-emitting duration control circuit 200 outputs a duration control signal based on the ramp signal Sweep and the second power supply voltage VGH.

[0088] As the slope signal Sweep gradually changes, such as gradually increasing, the pulse width modulation transistor gradually turns on from the off state, thereby controlling the duration of the output potential to the first potential according to the second power supply voltage VGH.

[0089] During this stage, the duration control signal changes from the second potential to the first potential. The switching circuit 300 is turned on according to the duration control signal of the first potential. After the switching circuit 300 is turned on, the driving transistor T1 drives the light-emitting device D to emit light according to the brightness control signal.

[0090] The driving timing of the aforementioned pixel circuit includes three stages, which can increase the proportion of the light-emitting stage in the display stage, thereby increasing the light-emitting duration of the light-emitting device D and achieving higher brightness display control. During the data writing and threshold voltage compensation stages, threshold voltage compensation is performed in both the brightness control circuit 100 and the light-emitting duration control circuit 200, which can improve the consistency between the driving transistor T1 and the pulse width modulation transistor. Furthermore, using a gradually changing slope signal (Sweep) to control the light-emitting time makes the change in the first potential more reliable, thereby achieving more precise control of the display brightness and improving the uniformity of grayscale transitions.

[0091] In some embodiments, such as Figure 3As shown, the reset circuit includes a first reset transistor T2 and a second reset transistor T3. The first terminal of the first reset transistor T2 is connected to the third power supply voltage VDD, the second terminal of the first reset transistor T2 is connected to the brightness control circuit 100, and the control terminal of the first reset transistor T2 is connected to the reset scan signal S1. The first terminal of the second reset transistor T3 is connected to the light emission duration control circuit 200, the second terminal of the second reset transistor T3 is connected to the initialization voltage signal Vint, and the control terminal of the second reset transistor T3 is connected to the reset scan signal S1.

[0092] Under the action of the reset scan signal S1, the first reset transistor T2 is turned on, transmitting the third power supply voltage VDD to the brightness control circuit 100, thus resetting the brightness control circuit 100. The second reset transistor T3 is turned on, transmitting the initialization voltage signal Vint to the light emission duration control circuit 200, thus resetting the light emission duration control circuit 200.

[0093] In this embodiment, the reset circuit has a simple structure and a small number of components. Furthermore, the control timing of the first reset transistor T2 and the second reset transistor T3 is identical, which simplifies the control timing of the pixel circuit.

[0094] In actual implementation, the reset circuit can also be configured according to specific needs, such as including a third reset transistor. The third reset transistor is connected to the cathode of the light-emitting device D and is controlled by the reset scan signal S1 to reset the cathode of the light-emitting device D during the reset phase, thereby further improving the accuracy of light emission.

[0095] In some embodiments, such as Figure 4 As shown, the brightness control circuit 100 includes a first transistor T4 and a first capacitor C1. The first terminal of the first transistor T4 is connected to the first terminal of the first transistor T4, the first terminal of the switching circuit 300, and the first terminal of the first capacitor C1. The second terminal of the first transistor T4 is used to receive the amplitude modulation signal Data_PAM, and the second terminal of the first capacitor C1 is grounded.

[0096] The width-to-length ratio of the first transistor T4 is the same as that of the driving transistor T1. Therefore, the threshold voltage of the first transistor T4 is equal to that of the driving transistor T1.

[0097] When the first transistor T4 is connected to the amplitude modulation signal Data_PAM, threshold compensation is performed based on the amplitude modulation signal Data_PAM. The voltage of node A after threshold compensation is the voltage of the brightness control signal. When the switching circuit 300 is turned on, this voltage is equivalent to achieving threshold voltage compensation for the driving transistor T1, thereby improving display uniformity.

[0098] Specifically, the second terminal of the first reset transistor T2 is connected to node A. Under the action of the reset scan signal S1, the first reset transistor T2 is turned on, transmitting the third power supply voltage VDD to node A and charging the first capacitor C1.

[0099] After the first transistor T4 is connected to the amplitude modulation signal Data_PAM, the potential of node A discharges to the input terminal of the amplitude modulation signal Data_PAM until the potential of node A reaches... =V Data_PAM +V th The first transistor T4 is turned off. Among them, This represents the potential of node A. This represents the voltage of the amplitude modulation signal Data_PAM, in V. th This represents the threshold voltage of the first transistor T4.

[0100] As can be seen, the potential of the brightness control signal at this time (i.e. the potential of node A) is the potential after threshold compensation. When the driving transistor T1 generates a driving current based on the brightness control signal to drive the light-emitting device D, the driving current will not be affected by the threshold voltage of the driving transistor T1, thereby improving the display uniformity.

[0101] In some embodiments, the light emission duration control circuit 200 includes a pulse width control unit 210, a first light emission control unit 220, and a second light emission control unit 230.

[0102] The pulse width control unit 210 is used to receive the data voltage signal Data_PWM and perform threshold voltage compensation based on the data voltage signal Data_PWM.

[0103] The first light-emitting control unit 220 connects the control terminal of the switching circuit 300 and the pulse width control unit 210. The first light-emitting control unit 220 is also used to receive the light-emitting control signal EM, and under the action of the light-emitting control signal EM, conducts the connection between the control terminal of the switching circuit 300 and the pulse width control unit 210.

[0104] The second light-emitting control unit 230 is connected to the pulse width control unit 210. The second light-emitting control unit 230 is used to access the second power supply voltage VGH and the light-emitting control signal EM, and is turned on under the action of the light-emitting control signal EM to transmit the second power supply voltage VGH to the pulse width control unit 210.

[0105] The pulse width control unit 210 is also used to receive the slope signal Sweep, and under the action of the slope signal Sweep, output a duration control signal with the first potential based on the second power supply voltage VGH.

[0106] In this embodiment, the pulse width control unit 210 receives the data voltage signal Data_PWM during the data writing and threshold voltage compensation stages. Based on the received data voltage signal Data_PWM, the pulse width modulation transistor in the pulse width control unit 210 performs threshold voltage compensation.

[0107] It should be noted that during the reset phase and the data writing and threshold voltage compensation phases, the light emission control signal EM is not connected or the light emission control signal EM is at an invalid potential. Therefore, during the threshold voltage compensation process of the pulse width modulation transistor in the pulse width control unit 210, the transistors in the first light emission control unit 220 and the second light emission control unit 230 are both in the off state. At this time, the control terminal of the switching circuit 300 receives a low potential, i.e., the duration control signal of the second potential.

[0108] During the light emission stage, under the action of the light emission control signal EM, the transistors in the first light emission control unit 220 and the second light emission control unit 230 are turned on, and the second light emission control unit 230 transmits the second power supply voltage VGH to the pulse width control unit 210.

[0109] The pulse width control unit 210 is also connected to a ramp signal Sweep. Under the action of the ramp signal Sweep, the pulse width modulation transistor is gradually turned on, thereby outputting a duration control signal with the first potential based on the second power supply voltage VGH.

[0110] Thus, the coordinated operation of the pulse width control unit 210, the first light-emitting control unit 220, and the second light-emitting control unit 230 enables the output of a corresponding duration control signal based on the data voltage signal Data_PWM. By configuring the first light-emitting control unit 220, the connection between the pulse width control unit 210 and the control terminal of the switching circuit 300 can be disconnected during the process of the pulse width control unit 210 writing the data voltage signal Data_PWM and performing threshold compensation, thus preventing false triggering of the switching circuit 300 and consequently avoiding false light emission. By configuring the second light-emitting control unit 230, the transmission of the second power supply voltage VGH to the pulse width control unit 210 can be stopped during the process of the pulse width control unit 210 writing the data voltage signal Data_PWM and performing threshold compensation, ensuring that the pulse width control unit 210 writes an accurate data voltage signal Data_PWM, thereby improving display accuracy.

[0111] In some embodiments, such as Figure 5 As shown, the first light-emitting control unit 220 includes a fifth transistor T5. The first terminal of the fifth transistor T5 is connected to the control terminal of the switching circuit 300, the second terminal of the fifth transistor T5 is connected to the pulse width control unit 210, and the control terminal of the fifth transistor T5 is used to receive the light-emitting control signal EM.

[0112] During the light-emitting phase, the light-emitting control signal EM controls the fifth transistor T5 to conduct, thus turning on the switching circuit 300. During the non-light-emitting phase (reset phase or data writing and threshold voltage compensation phase), the light-emitting control signal EM controls the fifth transistor T5 to deactivate, which can cut off the voltage supply to the control terminal of the switching circuit 300, thereby avoiding false triggering of the switching circuit 300 to conduct and improving the accuracy of light-emitting control.

[0113] In some embodiments, the second light-emitting control unit 230 includes a sixth transistor T6. The first terminal of the sixth transistor T6 is connected to the pulse width control unit 210, the second terminal of the sixth transistor T6 is used to connect to the second power supply voltage VGH, and the control terminal of the sixth transistor T6 is used to connect to the light-emitting control signal EM.

[0114] During the light-emitting phase, the light-emitting control signal EM also controls the sixth transistor T6 to turn on, transmitting the second power supply voltage VGH to the pulse width control unit 210. During the non-light-emitting phase, the light-emitting control signal EM controls the sixth transistor T6 to turn off, which cuts off the transmission path of the second power supply voltage VGH, preventing the second power supply voltage VGH from affecting the accuracy of the data written by the pulse width control unit 210, thereby improving the reliability of the display.

[0115] In some embodiments, the pixel circuit includes a seventh transistor T7. The first terminal of the seventh transistor T7 is connected to the second terminal of the driving transistor T1, the second terminal of the seventh transistor T7 is used to access the first power supply voltage VSS, and the control terminal of the seventh transistor T7 is used to access the light emission control signal EM.

[0116] During the light-emitting phase, under the action of the light-emitting control signal EM, the seventh transistor T7 is turned on, forming a circuit with the third power supply voltage VDD, the light-emitting device D, the driving transistor T1, the seventh transistor T7, and the first power supply voltage VSS, causing the light-emitting device D to emit light. During the non-light-emitting phase, the seventh transistor T7 is turned off by the light-emitting control signal EM, cutting off the current supply to the light-emitting device D and preventing it from emitting light. Therefore, by setting the seventh transistor T7, the accuracy of light-emitting control can be improved.

[0117] In some embodiments, the pulse width control unit 210 includes a second transistor T8, a third transistor T9, a fourth transistor T10, and a second capacitor C2. The first terminal of the second transistor T8 is connected to the first terminal of the first light-emitting control unit 220 and the third transistor T9. The second terminal of the third transistor T9 is connected to the control terminal of the second transistor T8 and the first terminal of the second capacitor C2. The second terminal of the second capacitor C2 is used to connect to the Sweep signal. The second terminal of the second transistor T8 is connected to the second light-emitting control unit 230 and the first terminal of the fourth transistor T10. The second terminal of the fourth transistor T10 is used to connect to the Data_PWM data voltage signal. The control terminals of both the third transistor T9 and the fourth transistor T10 are connected to the write scan signal S2.

[0118] During the data writing and threshold voltage compensation phase, under the action of the write scan signal S2, the third transistor T9 and the fourth transistor T10 are turned on. The data voltage signal Data_PWM is transmitted to node B through the fourth transistor T10, the second transistor T8, and the third transistor T9, and charges the second capacitor C2 until the potential of node B reaches V. B =V Data_PWM +V th8 The second transistor T8 is turned off. Wherein, V B The voltage at node B is represented by V. Data_PWM This represents the voltage of the data voltage signal Data_PWM, in V. TH8 This represents the threshold voltage of the second transistor T8. Thus, the writing of the data voltage signal Data_PWM and the threshold voltage compensation of the second transistor T8, which acts as a pulse width modulation transistor, are completed.

[0119] During the light-emitting phase, as the slope signal Sweep gradually increases and the coupling effect of the second capacitor C2 occurs, the potential of node B gradually rises until the second transistor T8 is turned on. After the second transistor T8 is turned on, it receives the second power supply voltage signal VGH transmitted by the second light-emitting control unit 230 and outputs it through the first light-emitting control unit 220, thereby enabling the control terminal of the switching circuit 300 to receive the signal at the first potential. This process is not affected by the threshold voltage of the second transistor T8, resulting in higher reliability of the signal output to the switching circuit 300.

[0120] In this embodiment, the pulse width control unit 210 can adjust the duration ratio of the first potential of its output signal according to the data voltage signal Data_PWM to control the light emission duration. The output signal of the pulse width control unit 210 has high reliability, thereby ensuring high reliability in controlling the on / off state of the switching circuit 300, and thus improving the accuracy of light emission control.

[0121] In this embodiment, the first terminal of the second reset transistor T3 can be connected to the control terminal of the second transistor T8. During the reset phase, under the action of the reset scan signal S1, the second reset transistor T3 is turned on, transmitting the initialization voltage signal Vint to the control terminal of the second transistor T8, resetting the control terminal of the second transistor T8 and the second capacitor C2. Therefore, the reset of the control terminal of the second transistor T8 and the second capacitor C2 can be completed before the data voltage signal Data_PWM is written to node B, avoiding any adverse effects of the data voltage signal Data_PWM from the previous display phase on the current display phase, and improving display accuracy.

[0122] In practical implementation, the potential of the duration control signal can be determined based on the type of the eighth transistor T11. It can be understood that when the eighth transistor T11 is an N-type transistor, the first potential is high and the second potential is low. When the eighth transistor T11 is a P-type transistor, the first potential is low and the second potential is high.

[0123] In some embodiments, the switching circuit 300 includes an eighth transistor T11. The first terminal of the eighth transistor T11 serves as the first terminal of the switching circuit 300 and is connected to the brightness control circuit 100; the second terminal of the eighth transistor T11 serves as the second terminal of the switching circuit 300 and is connected to the control terminal of the driving transistor T1; the control terminal of the eighth transistor T11 serves as the control terminal of the switching circuit 300 and is connected to the light emission duration control circuit 200.

[0124] In this embodiment, the switching circuit 300 includes an eighth transistor T11, which has a small number of components and a simple circuit structure, thereby simplifying the circuit structure of the pixel circuit.

[0125] It should be noted that all the transistors mentioned above can be TFTs (Thin Film Transistors). The type of each transistor can be set according to specific circumstances; it can be an N-type transistor or a P-type transistor. The gate is the control electrode of each transistor, and the first and second electrodes can be determined according to the specific type of transistor.

[0126] The following is combined Figure 5 The specific circuit structure of the pixel circuit in this embodiment will be described in detail.

[0127] In this embodiment, the pixel circuit includes a driving transistor T1, a brightness control circuit 100, a light emission duration control circuit 200, a switching circuit 300, a reset circuit 400, and a seventh transistor T7.

[0128] The first terminal of the driving transistor T1 is used to connect to the cathode of the light-emitting device D, the second terminal of the driving transistor T1 is used to connect to the first power supply voltage VSS, and the anode of the light-emitting device D is connected to the third power supply voltage VDD.

[0129] The brightness control circuit 100 includes a first transistor T4 and a first capacitor C1. The first terminal of the first transistor T4 is connected to the first terminal of the first transistor T4, the first terminal of the switching circuit 300, and the first terminal of the first capacitor C1. The second terminal of the first transistor T4 is used to receive the amplitude modulation signal Data_PAM, and the second terminal of the first capacitor C1 is grounded. The amplitude modulation signal Data_PAM is a constant voltage signal.

[0130] The light emission duration control circuit 200 includes a pulse width control unit 210, a first light emission control unit 220, and a second light emission control unit 230.

[0131] The pulse width control unit 210 includes a second transistor T8, a third transistor T9, a fourth transistor T10, and a second capacitor C2. The first terminal of the second transistor T8 is connected to the first terminal of the first light-emitting control unit 220 and the third transistor T9. The second terminal of the third transistor T9 is connected to the control terminal of the second transistor T8 and the first terminal of the second capacitor C2. The second terminal of the second capacitor C2 is used to connect to the slope signal Sweep. The second terminal of the second transistor T8 is connected to the second light-emitting control unit 230 and the first terminal of the fourth transistor T10. The second terminal of the fourth transistor T10 is used to connect to the data voltage signal Data_PWM. The control terminals of both the third transistor T9 and the fourth transistor T10 are connected to the write scan signal S2.

[0132] The first light-emitting control unit 220 includes a fifth transistor T5. The first terminal of the fifth transistor T5 is connected to the control terminal of the switching circuit 300, the second terminal of the fifth transistor T5 is connected to the pulse width control unit 210, and the control terminal of the fifth transistor T5 is used to receive the light-emitting control signal EM.

[0133] The second light-emitting control unit 230 includes a sixth transistor T6. The first terminal of the sixth transistor T6 is connected to the pulse width control unit 210, the second terminal of the sixth transistor T6 is used to connect to the second power supply voltage VGH, and the control terminal of the sixth transistor T6 is used to connect to the light-emitting control signal EM.

[0134] The first terminal of the seventh transistor T7 is connected to the second terminal of the driving transistor T1. The second terminal of the seventh transistor T7 is used to connect to the second power supply voltage VGH. The control terminal of the seventh transistor T7 is used to connect to the light emission control signal EM.

[0135] The switching circuit 300 includes an eighth transistor T11. The first terminal of the eighth transistor T11 is connected to the brightness control circuit 100; the second terminal of the eighth transistor T11 is connected to the control terminal of the driving transistor T1; and the control terminal of the eighth transistor T11 is connected to the light emission duration control circuit 200.

[0136] The reset circuit 400 includes a first reset transistor T2 and a second reset transistor T3. The first terminal of the first reset transistor T2 is connected to a third power supply voltage VDD, the second terminal of the first reset transistor T2 is connected to the brightness control circuit 100, and the control terminal of the first reset transistor T2 is connected to the reset scan signal S1. The first terminal of the second reset transistor T3 is connected to the light emission duration control circuit 200, the second terminal of the second reset transistor T3 is connected to the initialization voltage signal Vint, and the control terminal of the second reset transistor T3 is connected to the reset scan signal S1.

[0137] The aforementioned pixel circuit structure includes 11 transistors and 2 capacitors. With fewer components and a simpler circuit structure, it can increase the PPI (Pixels Per Inch) of the display device. By making the amplitude modulation signal Data_PAM a constant voltage signal, constant current driving is achieved for the light-emitting device D, thereby improving display uniformity. The brightness and duration of the light-emitting device D are adjusted through the brightness control circuit 100, the light-emitting duration control circuit 200, and the switching circuit 300. This allows for more precise control of the display brightness of the light-emitting device D by the pixel circuit, achieving higher grayscale brightness display.

[0138] Based on the above-described pixel circuit structure, the control process of the pixel circuit in this embodiment includes at least a data writing and threshold voltage compensation stage. In some embodiments, the control process also includes a reset stage.

[0139] The following is combined Figure 6 , Figure 6 The diagram illustrates the waveforms of the reset scan signal S1, write scan signal S2, light emission control signal EM, data voltage signal Data_PWM, amplitude modulation signal Data_PAM, and ramp signal Sweep in three stages within one frame display cycle in this embodiment. Based on these three stages and the circuit structure of the pixel circuit described above, the control process of the pixel circuit in this embodiment is described in detail.

[0140] During the reset phase, refer to Figures 6-7 ( Figure 7(A cross indicates the transistor is not conducting). The reset scan signal S1 goes high, turning on the first reset transistor T2 and the second reset transistor T3. The third power supply voltage VDD charges the first capacitor C1 through the first reset transistor T2, and the potential of node A is the third power supply voltage VDD. The initialization voltage signal Vint charges the second capacitor C2 through the second reset transistor T3, and the potential of node B is the potential of the initialization voltage signal Vint. The second transistor T8 is in the conducting state.

[0141] During the data writing and threshold compensation phases, refer to Figure 6 , Figures 8-9 ( Figures 8-9 (A cross indicates the transistor is not conducting). When the reset scan signal S1 is low, the first reset transistor T2 and the second reset transistor T3 are off, and the first transistor T4 is on. Node A discharges to the input terminal of the amplitude modulation signal Date_PAM until the potential at point A reaches... =V Data_PAM +V th The first transistor T4 is turned off.

[0142] When the write scan signal S2 goes high, the second transistor T8 and the fourth transistor T10 are turned on. The data voltage signal Data_PWM charges the second capacitor C2 through the fourth transistor T10, the second transistor T8, and the third transistor T9 until the potential of node B reaches V. B =V Data_PWM +V th8 The second transistor T8 is turned off.

[0143] During the writing phase, refer to Figure 6 , Figures 10-11 ( Figures 10-11 (A cross indicates the transistor is not conducting). The light-emitting control signal EM goes high, and transistors T5, T6, and T7 turn on. As the potential of the slope voltage Sweep increases and due to the coupling effect of the second capacitor C2, the potential of node B changes from V... B =V Data_PWM +V th8 The voltage gradually increases until the second transistor T8 is turned on. The second power supply voltage VGH is applied to the gate of the eighth transistor T11, turning on the eighth transistor T11. Node A is connected to the gate of the driving transistor T1. The threshold voltage compensation of the first transistor T4 is applied to the driving transistor T1, compensating for the threshold voltage of the driving transistor T1. The driving transistor T1 is then turned on, and the light-emitting device D emits light.

[0144] Based on this, in this embodiment, by changing the voltage control of the data voltage signal Data_PWM, the conduction time of the second transistor T8 in the light-emitting stage is controlled, thereby controlling the time when the first potential is output to the gate of the eighth transistor T11, thus controlling the conduction time of the eighth transistor T11, thereby controlling the connection time between node A and the gate of the driving transistor T1, thereby controlling the conduction duration of the driving transistor T1, and further controlling the light-emitting duration of the light-emitting element D, so as to achieve the purpose of displaying different brightness.

[0145] The driving timing of this pixel circuit includes three stages. The light-emitting stage accounts for a large proportion of the display stage, thereby increasing the light-emitting duration of the light-emitting device D and achieving higher brightness display control. During the data writing and threshold voltage compensation stages, threshold voltage compensation is performed in both the brightness control circuit 100 and the light-emitting duration control circuit 200, which improves the consistency between the driving transistor T1 and the pulse width modulation transistor. Furthermore, using a gradually changing slope signal (Sweep) to control the light-emitting time makes the change in the first potential more reliable, thereby achieving more precise control of the display brightness and improving the uniformity of grayscale transitions.

[0146] It is understood that the pixel circuit described above can also take other forms, and is not limited to the forms already mentioned in the above embodiments, as long as it can achieve the function of pixel driving.

[0147] This embodiment also provides a pixel circuit control method, applied to the display device in the above embodiment. The display device further includes a driver chip, which is used to output an amplitude modulation signal so that the brightness control circuit outputs a brightness control signal according to the amplitude modulation signal; and to output a data voltage signal and a ramp signal so that the light emission duration control circuit outputs a duration control signal according to the data voltage signal, the ramp signal, and the second power supply voltage.

[0148] In one embodiment, such as Figure 12 As shown, the control method for this pixel circuit includes:

[0149] Step 602: Output an amplitude modulation signal so that the brightness control circuit outputs a brightness control signal according to the amplitude modulation signal.

[0150] Step 604: Output data voltage signal and ramp signal so that the light emission duration control circuit outputs duration control signal according to data voltage signal, ramp signal and second power supply voltage.

[0151] The duration control signal has two potentials: a first potential and a second potential. When the duration control signal is at the first potential, the switching circuit is turned on according to the duration control signal, so that the driving transistor drives the light-emitting device to emit light according to the brightness control signal; when the duration control signal is at the second potential, the switching circuit is turned off according to the duration control signal.

[0152] In some embodiments, such as Figure 13 As shown, steps 602-604 include the following steps:

[0153] Step 702: In the first stage, an amplitude modulation signal and a data voltage signal are output so that the brightness control circuit outputs a brightness control signal according to the amplitude modulation signal; the light emission duration control circuit performs threshold voltage compensation according to the data voltage signal and outputs a duration control signal, the potential of which is the second potential.

[0154] Step 704: In the second stage, a ramp signal is output so that the light emission duration control circuit outputs a duration control signal based on the ramp signal and the second power supply voltage. The potential change of the duration control signal is the first potential.

[0155] In some embodiments, such as Figure 14 As shown, the control method for this pixel circuit also includes the following steps:

[0156] Step 701: In the third stage, a reset scan signal is output so that the reset circuit resets the brightness control circuit and the light emission duration control circuit.

[0157] It can be understood that the first stage is the data writing and threshold compensation stage, the second stage is the light emission stage, and the third stage is the reset stage. In one frame display cycle, the control timing of the control chip can be in the following order: the third stage, the first stage, and the second stage, i.e., the reset stage, the data writing and threshold compensation stage, and the light emission stage.

[0158] The specific implementation of the pixel circuit control method in this embodiment is consistent with the implementation of the relevant embodiments of the pixel circuit described above, and will not be repeated here.

[0159] It should be understood that although the steps in the flowcharts of the embodiments described above are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the embodiments described above may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages of other steps.

[0160] It should be noted that, in the embodiments of this application, "display device" refers to any device with screen display and data processing capabilities. For example, display devices include, but are not limited to, smart TVs, mobile terminals, computers, monitors, advertising screens, wearable devices, virtual reality devices, and augmented reality devices.

[0161] In the description of this specification, references to terms such as "some embodiments," "other embodiments," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative descriptions of the above terms do not necessarily refer to the same embodiments or examples.

[0162] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0163] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these modifications and improvements all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A display device, characterized by comprising: The display device includes a pixel circuit, the pixel circuit comprising: A driving transistor, wherein the first terminal of the driving transistor is used to connect to a light-emitting device, and the second terminal of the driving transistor is used to connect to a first power supply voltage; A brightness control circuit is provided, wherein the brightness control circuit is used to receive an amplitude modulation signal and output a brightness control signal according to the amplitude modulation signal; A light emission duration control circuit is provided, wherein the light emission duration control circuit is used to receive a data voltage signal, a ramp signal, and a second power supply voltage, and outputs a duration control signal according to the data voltage signal, the ramp signal, and the second power supply voltage; the potential of the duration control signal includes a first potential and a second potential; A switching circuit, wherein the first terminal of the switching circuit is connected to the brightness control circuit, the second terminal of the switching circuit is connected to the control electrode of the driving transistor, and the control terminal of the switching circuit is connected to the light emission duration control circuit. Specifically, when the duration control signal is at the first potential, the switching circuit is turned on so that the driving transistor drives the light-emitting device to emit light according to the brightness control signal; when the duration control signal is at the second potential, the switching circuit is turned off.

2. The display device according to claim 1, characterized in that, The amplitude modulation signal is a constant voltage signal, and the voltage of the amplitude modulation signal is positively correlated with the voltage of the brightness control signal.

3. The display device according to claim 1, wherein The aspect ratio of the transistor in the brightness control circuit is the same as that of the driving transistor. The brightness control circuit is used to perform threshold compensation according to the amplitude modulation signal and output the brightness control signal.

4. The display device according to claim 3, wherein The brightness control circuit includes a first transistor and a first capacitor; the aspect ratio of the first transistor is the same as that of the driving transistor. The first terminal of the first transistor is connected to the control terminal of the first transistor, the first terminal of the switching circuit, and the first terminal of the first capacitor. The second terminal of the first transistor is used to receive the amplitude modulation signal, and the second terminal of the first capacitor is grounded.

5. The display device according to claim 1, wherein The light emission duration control circuit includes: A pulse width control unit is used to receive the data voltage signal and perform threshold voltage compensation based on the data voltage signal. The first light-emitting control unit is connected to the control terminal of the switching circuit and the pulse width control unit; the first light-emitting control unit is used to receive the light-emitting control signal and, under the action of the light-emitting control signal, to connect the control terminal of the switching circuit and the pulse width control unit. The second light-emitting control unit is connected to the pulse width control unit; the second light-emitting control unit is used to receive the second power supply voltage and the light-emitting control signal, and is turned on under the action of the light-emitting control signal to transmit the second power supply voltage to the pulse width control unit; The pulse width control unit is used to receive the ramp signal and, under the action of the ramp signal, output a duration control signal with the potential of the first potential according to the second power supply voltage.

6. The display device according to claim 5, characterized in that, The pulse width control unit includes a second transistor, a third transistor, a fourth transistor, and a second capacitor. The first terminal of the second transistor is connected to the first light-emitting control unit and the first terminal of the third transistor. The second terminal of the third transistor is connected to the control terminal of the second transistor and the first terminal of the second capacitor. The second terminal of the second capacitor is used to receive the ramp signal. The second terminal of the second transistor is connected to the second light-emitting control unit and the first terminal of the fourth transistor. The second terminal of the fourth transistor is used to receive the data voltage signal. The control terminals of the third transistor and the fourth transistor are both connected to a write scan signal.

7. The display device according to claim 5, characterized in that, The first light-emitting control unit includes a fifth transistor; the first terminal of the fifth transistor is connected to the control terminal of the switching circuit, the second terminal of the fifth transistor is connected to the pulse width control unit, and the control terminal of the fifth transistor is used to receive the light-emitting control signal; The second light-emitting control unit includes a sixth transistor; the first terminal of the sixth transistor is connected to the pulse width control unit, the second terminal of the sixth transistor is used to connect to the second power supply voltage, and the control terminal of the sixth transistor is used to connect to the light-emitting control signal.

8. The display device according to claim 1, characterized in that, The pixel circuit includes a seventh transistor; the first terminal of the seventh transistor is connected to the second terminal of the driving transistor, the second terminal of the seventh transistor is used to connect to the first power supply voltage, and the control terminal of the seventh transistor is used to connect to the light emission control signal.

9. The display device according to claim 1, characterized in that, The switching circuit includes an eighth transistor; the first terminal of the eighth transistor is connected to the brightness control circuit, the second terminal of the eighth transistor is connected to the control terminal of the driving transistor, and the control terminal of the eighth transistor is connected to the light emission duration control circuit.

10. The display device according to any one of claims 1-9, characterized in that, The pixel circuit includes a reset circuit, which is connected to the brightness control circuit and the light emission duration control circuit respectively; the reset circuit is used to receive a reset scan signal and reset the brightness control circuit and the light emission duration control circuit according to the reset scan signal.

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