Patent Application
20240071289
This application claims priority to Chinese Patent Application No. 202211026510.7, filed on Aug. 25, 2022, which is incorporated herein by reference in its entirety.
The present application relates to a technical field of display, and particularly relates to a pixel circuit and a driving method thereof, a display panel and a display device.
Currently, a display panel can be displayed with different refresh rates in different modes. For example, in a video mode or in a game mode, a driving mode with a high refresh rate can be used to drive the display panel to display dynamic pictures, thereby ensuring the fluency of the displayed pictures. For example, when some static pictures are displayed, a driving mode with a low refresh rate can be used to drive the display panel to display the static pictures, thereby reducing the power consumption.
The inventor of the present application has found that there is a problem of screen flashing when the display panel is displayed at a low refresh rate.
The embodiments of the present application provide a pixel circuit and a driving method thereof, a display panel and a display device.
In a first aspect, the embodiments of the present application provide a pixel circuit, including: a driving module configured to drive a light-emitting element to emit light; a first bias module electrically connected to a first terminal or a second terminal of the driving module, wherein the first bias module is configured to provide a first bias signal to the first terminal or the second terminal of the driving module, and the first bias signal is configured to adjust a bias state of the driving module; wherein a light-emitting cycle of the light-emitting element includes a refresh frame or a hold frame, wherein a control terminal of the driving module is refreshed in the refresh frame, and the control terminal of the driving module is not refreshed in the hold frame; each of the refresh frame and the hold frame includes a first stage and a second stage, the first stage is located before the second stage, the first stage includes one or more bias stages, and the second stage includes a light-emitting stage of the light-emitting element, and wherein in the bias stages, the first bias module is turned on, and the first bias signal is transmitted to the first terminal or the second terminal of the driving module; wherein a turn-on duration of the first bias module in the hold frame is longer than a turn-on duration of the first bias module in the refresh frame; and/or, a time interval between a turn-on start moment of the first bias module in the hold frame and the light-emitting stage in the hold frame is greater than a time interval between a turn-on start moment of the first bias module in the refresh frame and the light-emitting stage in the refresh frame; and/or a turn-on stage of the first bias module in the refresh frame at least partially overlaps with other bias stages in the refresh frame.
In a second aspect, the embodiments of the present application provide a driving method of a pixel circuit, wherein the pixel circuit includes: a driving module configured to drive a light-emitting element to emit light; a first bias module electrically connected to a first terminal or a second terminal of the driving module, wherein the first bias module is configured to provide a first bias signal to the first terminal or the second terminal of the driving module, and the first bias signal is configured to adjust a bias state of the driving module; wherein a light-emitting cycle of the light-emitting element includes a refresh frame or a hold frame, wherein a control terminal of the driving module is refreshed in the refresh frame, and the control terminal of the driving module is not refreshed in the hold frame; each of the refresh frame and the hold frame includes a first stage and a second stage, the first stage is located before the second stage, the first stage includes one or more bias stages, and the second stage includes a light-emitting stage of the light-emitting element; the driving method includes: in the bias stages, controlling the first bias module to be turned on, and transmitting the first bias signal to the first terminal or the second terminal of the driving module; wherein a turn-on duration of the first bias module in the hold frame is longer than a turn-on duration of the first bias module in the refresh frame; and/or, a time interval between a turn-on start moment of the first bias module in the hold frame and the light-emitting stage in the hold frame is greater than a time interval between a turn-on start moment of the first bias module in the refresh frame and the light-emitting stage in the refresh frame; and/or a turn-on stage of the first bias module in the refresh frame at least partially overlaps with other bias stages in the refresh frame.
In a third aspect, the embodiments of the present application provide a display panel including the pixel circuit provided in the first aspect.
In a fourth aspect, the embodiments of the present application provide a display device including the display panel provided in the third aspect.
In order to illustrate technical solutions of embodiments of the present application more clearly, the drawings required for the embodiments of the present application will be briefly described. For a person skilled in the art, other drawings can also be obtained from these drawings without any inventive efforts.
The features and exemplary embodiments of various aspects of the present application will be described in detail below. In order to make the purpose, technical solutions and advantages of the present application more clear, the present application will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only intended to explain the present application, but not to limit the present application. It will be apparent to a person skilled in the art that the present application may be practiced without some of these specific details. The following description of the embodiments is merely to provide a better understanding of the present application by illustrating examples of the present application.
It should be noted that, in this document, relational terms such as first and second are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply such an actual relationship or sequence between these entities or operations. Moreover, the terms “including”, “including” or any other variation thereof are intended to encompass a non-exclusive inclusion such that a process, method, article or device that includes a list of elements includes not only those elements, but also includes other elements that are not explicitly listed but inherent to such a process, method, article or device. Without further limitation, an element defined by the term “including . . . ” does not preclude presence of additional elements in a process, method, article or device that includes the element.
It should be understood that the term “and/or” used herein is just a related relationship that describes associated objects, and indicates that there can be three relationships. For example, A and/or B may indicate three cases: A alone, A and B, and B alone. In addition, the character “/” used herein generally indicates that the relationship between the front and back associated objects is a “or” relationship.
It should be noted that the transistor in the embodiments of the present application may be an N-type transistor or a P-type transistor. For the N-type transistor, the turn-on level is a high level, and the turn-off level is a low level. That is, under a condition that the gate of the N-type transistor is at the high level, the first electrode and the second electrode of the N-type transistor are turned on. Further, under a condition that the gate of the N-type transistor is at the low level, the first electrode and the second electrode of the N-type transistor are turned off. For the P-type transistor, the turn-on level is a low level, and the turn-off level is a high level. That is, under a condition that the gate of the P-type transistor is at the low level, the first electrode and the second electrode of the P-type transistor are turned on. Further, under a condition that the gate of the P-type transistor is at the high level, the first electrode and the second electrode of the P-type transistor are turned off. In specific implementations, the gate of the transistor may be used as the control electrode. Further, according to the signal of the gate of the transistor and the type of the transistor, the first electrode may be the source and the second electrode may be the drain, or the first electrode may be the drain and the second electrode may be the source, which is not limited here. In addition, the turn-on level and the turn-off level in the embodiments of the present application are generalized, the turn-on level may refer to any level that can turn on the transistor, and the turn-off level may refer to any level that can turn off the transistor.
In the embodiments of the present application, the term “electrically connected” may indicate that the two components are directly electrically connected, or may indicate that the two components are electrically connected through one or more other components.
In the embodiments of the present application, a first node, a second node, and a third node are defined only to facilitate the description of the circuit structure. Further, the first node, the second node, and the third node are not actual circuit units.
It is obvious to those skilled in the art that various modifications and changes can be made in the present application without departing from the spirit or scope of the present application. Therefore, the present application is intended to cover the modifications and changes of the present application within the scope of the corresponding claims (the claimed technical solutions) and their equivalents. It should be noted that the implementations provided by the embodiments of the present application may be combined with each other without contradiction.
Before explaining the technical solutions provided by the embodiments of the present application, in order to facilitate the understanding of the embodiments of the present application, the present application firstly describes the problems existing in the related art.
As mentioned above, the inventor of the present application found that in the related art, there is a problem of screen flashing when the display panel is displayed at a low refresh rate.
In order to solve the above technical problem, the inventor of the present application has firstly conducted research and analysis of the root causes of the above technical problem. The specific research and analysis process is as follows.
When the display panel is displayed at a low refresh rate, a refresh cycle may include a refresh frame and a hold frame. In the hold frame, the control terminal of the driving module in the pixel circuit does not refresh, thereby reducing the power consumption. Here, for example, the low refresh rate may include a refresh rate of 1 Hz, 2 Hz, 10 Hz or other Hertz, which is not limited by the embodiments of the present application.
The inventor of the present application has made the following researches.
In order to improve the problem of the first frame having low brightness caused by shift of the threshold voltage Vth of the driving module, a bias stage can be added to the refresh frame. Therefore, the potential of the second terminal of the driving module is equal to or greater than the potential of the control terminal of the driving module, and the driving module is in the on-bias (OBS) state. Further, the potential difference between the potential of the second terminal of the driving module and the potential of the control terminal of the driving module may be improved, and the extent of ion polarization inside the driving module may be weakened. Thus, the threshold voltage Vth of the driving module may be reduced, thereby adjusting the threshold voltage Vth of the driving module.
However, in this way, the time period that the driving module is in the OBS state in the refresh frame is greater than the time period that the driving module is in the OBS state in the hold frame. Further, the difference between the threshold voltage Vth of the driving module in the refresh frame and the threshold voltage Vth of the driving module in the hold frame is large. Therefore, the difference between the brightness of the refresh frame and the brightness of the hold frame is large, thereby causing the flashing problem of the display panel.
In view of the above research findings of the inventor, the embodiments of the present application provide a pixel circuit and a driving method thereof, a display panel and a display device, which can solve the technical problem of screen flashing when the display panel is displayed at the low refresh rate in the related art.
The technical idea of the embodiments of the present application is that: by increasing the turn-on duration of the first bias module in the hold frame, and/or increasing the time interval between the turn-on start moment of the first bias module in the hold frame and the light-emitting stage in the hold frame, and/or at least partially overlapping the turn-on stage of the first bias module in the refresh frame with other bias stages in the refresh frame, the time period that the driving module is in the on-bias state in the hold frame may be increased and/or the time period that the driving module is in the on-bias state in the refresh frame may be reduced. Further, the difference between the threshold voltage of the driving module in the hold frame and the threshold voltage of the driving module in the refresh frame may be improved, the difference between the brightness of the refresh frame and the brightness of the hold frame may be reduced, and the flashing problem may be improved.
The pixel circuit provided by the embodiments of the present application is firstly introduced below.
Combining
In the bias stages p, the first bias module 102 is turned on (or switched on), and the first bias signal is transmitted to the first terminal a or the second terminal b of the driving module 101. It should be noted that in the bias stages p, the driving module 101 may be in the turn-on state. Therefore, whether the first bias signal is transmitted to the first terminal a of the driving module 101 or the second terminal b of the driving module 101, the first bias signal can eventually be transmitted to the second terminal b of the driving module 101. It should be noted that in
The potential of the control terminal of the driving module 101 is usually negative, that is, less than 0V Therefore, in some embodiments, the voltage value of the first bias signal may be greater than 0V or may be negative, but it needs to be greater than or equal to the potential of the control terminal of the driving module 101.
After the first bias signal is transmitted to the second terminal b of the driving module 101, and until before the light-emitting stage, the driving module 101 is in the OBS state, thereby achieving the adjustment of the threshold voltage Vth of the driving module 101.
Combining
Thus, by increasing the time interval between the turn-on start moment of the first bias module in the hold frame F2 and the light-emitting stage in the hold frame F2, the time period that the driving module is in the OBS state in the hold frame F2 may be increased. Therefore, the difference between the time period that the driving module is in the OBS state in the hold frame F2 and the time period that the driving module is in the OBS state in the refresh frame F1 may be improved. Further, the difference between the threshold voltage of the driving module in the hold frame F2 and the threshold voltage of the driving module in the refresh frame F1 may be improved, the difference between the brightness of the refresh frame F1 and the brightness of the hold frame F2 may be reduced, and the flashing problem may be improved.
Continuing referring to
In some specific embodiments, the duration of the first bias stage p1 in the hold frame F2 may be greater than the duration of the first bias stage p1 in the refresh frame F1, and/or the time interval between the first bias stage p1 in the hold frame F2 and the light-emitting stage f in the hold frame F2 may be greater than the time interval between the first bias stage p1 in the refresh frame F1 and the light-emitting stage f in the refresh frame F1.
Thus, by increasing the duration of the first bias stage p1 in the hold frame F2, and/or increasing the time interval between the first bias stage p1 in the hold frame F2 and the light-emitting stage in the hold frame F2, the time period that the driving module is in the OBS state in the hold frame F2 may be increased. Therefore, the difference between the time period that the driving module is in the OBS state in the hold frame F2 and the time period that the driving module is in the OBS state in the refresh frame F1 may be improved. Further, the difference between the threshold voltage of the driving module in the hold frame F2 and the threshold voltage of the driving module in the refresh frame F1 may be improved, the difference between the brightness of the refresh frame F1 and the brightness of the hold frame F2 may be reduced, and the flashing problem may be improved.
To facilitate illustration, a time interval between a turn-on moment of the 1st pulse k1 of the first scan signal in the hold frame F2 and the light-emitting stage in the hold frame F2 is referred to as a first time interval T1′, and a time interval between a turn-on moment of the 1st pulse k1 of the first scan signal in the refresh frame F1 and the light-emitting stage in the refresh frame F1 is referred to as a second time interval T2′. Under a condition that the first scan signal is a low level and the first bias module is turned on (or switched on), the first time interval T1′ may refer to the time interval between a falling edge of the 1st pulse k1 of the first scan signal in the hold frame F2 and the light-emitting stage in the hold frame F2, and the second time interval T2′ may refer to the time interval between a falling edge of the 1st pulse k1 of the first scan signal in the refresh frame F1 and the light-emitting stage in the refresh frame F1. Here, the first time interval T1′ is greater than the second time interval T2′.
Thus, by increasing the time interval between the turn-on moment of the 1st pulse k1 of the first scan signal in the hold frame F2 and the light-emitting stage in the hold frame F2 (that is, the first time interval T1′), the time period that the driving module is in the OBS state in the hold frame F2 may be increased. Therefore, the difference between the time period that the driving module is in the OBS state in the hold frame F2 and the time period that the driving module is in the OBS state in the refresh frame F1 may be improved. Further, the difference between the threshold voltage of the driving module in the hold frame F2 and the threshold voltage of the driving module in the refresh frame F1 may be improved, the difference between the brightness of the refresh frame F1 and the brightness of the hold frame F2 may be reduced, and the flashing problem may be improved.
Continuing referring to
Thus, the turn-on duration of the first bias module in the hold frame F2 may be greater than the turn-on duration of the first bias module in the refresh frame F1. That is, by increasing the turn-on duration of the first bias module in the hold frame F2, the time period that the driving module is in the OBS state in the hold frame F2 may be increased. Therefore, the difference between the time period that the driving module is in the OBS state in the hold frame F2 and the time period that the driving module is in the OBS state in the refresh frame F1 may be improved. Further, the difference between the threshold voltage of the driving module in the hold frame F2 and the threshold voltage of the driving module in the refresh frame F1 may be improved, the difference between the brightness of the refresh frame F1 and the brightness of the hold frame F2 may be reduced, and the flashing problem may be improved.
That is, the number of the pulses k of the first scan signal in the hold frame F2 may be greater than the number of the pulses k of the first scan signal in the refresh frame F1. For example, in some specific examples, the number of the pulses k of the first scan signal in the hold frame F2 is 3, and the number of the pulses k of the first scan signal in the refresh frame F1 is 2.
Since the number of the pulses k of the first scan signal in the hold frame F2 is greater than the number of the pulses k of the first scan signal in the refresh frame F1, the turn-on duration of the first bias module in the hold frame F2 may be greater than the turn-on duration of the first bias module in the refresh frame F1. Thus, by increasing the turn-on duration of the first bias module in the hold frame F2, the time period that the driving module is in the OBS state in the hold frame F2 may be increased. Therefore, the difference between the time period that the driving module is in the OBS state in the hold frame F2 and the time period that the driving module is in the OBS state in the refresh frame F1 may be improved. Further, the difference between the threshold voltage of the driving module in the hold frame F2 and the threshold voltage of the driving module in the refresh frame F1 may be improved, the difference between the brightness of the refresh frame F1 and the brightness of the hold frame F2 may be reduced, and the flashing problem may be improved.
It should be noted that in the embodiment shown in
Referring further to
Thus, not only the turn-on duration of the first bias module in the hold frame F2 is greater than the turn-on duration of the first bias module in the refresh frame F1, but also the first time interval T1′ is greater than the second time interval T2′. That is, the turn-on duration of the first bias module in the hold frame F2 is increased, meanwhile the time interval between the turn-on moment of the 1st pulse k1 of the first scan signal in the hold frame F2 and the light-emitting stage in the hold frame F2 (that is, the first time interval T1′) is increased. Thus, the time period that the driving module is in the OBS state in the hold frame F2 may be increased in two ways. Therefore, the difference between the time period that the driving module is in the OBS state in the hold frame F2 and the time period that the driving module is in the OBS state in the refresh frame F1 may be improved. Further, the difference between the threshold voltage of the driving module in the hold frame F2 and the threshold voltage of the driving module in the refresh frame F1 may be improved, the difference between the brightness of the refresh frame F1 and the brightness of the hold frame F2 may be reduced, and the flashing problem may be improved.
It should be noted that, similar to
In the data writing stage t81, the data writing module 103 may be turned on under a control of a second scan signal provided by the second scan signal terminal Scn2, and the data writing module 103 is configured to transmit the data signal provided by the data signal terminal data to the first terminal a or the second terminal b of the driving module 101. Specifically, in the data writing stage t81, the second scan signal terminal Scn2 may output the turn-on level (e.g., the low level), the data writing module 103 is turned on in response to the turn-on level output by the second scan signal terminal Scn2, and the data signal provided by the data signal terminal data is transmitted to the first terminal a or the second terminal b of the driving module 101 through the turned-on data writing module 103. For example, the second terminal b of the driving module 101 may be connected to the control terminal of the driving module 101, so that the data signal may be transmitted to the control terminal of the driving module 101 to achieve a control of the switching state of the driving module 101.
The inventor of the present application has found that, after the data signal is written to the driving module 101, the state of the driving module 101 is not too stable, and the threshold voltage Vth of the driving module will still change to a certain extent. Therefore, the threshold voltage Vth of the driving module will be unstable at the beginning of the light-emitting stage, resulting in the change of the light-emitting brightness at the beginning of the light-emitting stage.
In view of this, the present application considers to add a second bias stage between the data writing stage and the light-emitting stage, and to adjust the threshold voltage Vth of the driving module again. Therefore, the characteristic curve of the driving module 101 is restored to the normal threshold voltage corresponding to when the data signal is written as soon as possible, thereby avoiding the change of the light-emitting brightness at the beginning of the light-emitting stage.
Specifically, at least the bias stages p of the refresh frame F1 may also include a second bias stage p2, and the second bias stage p2 is located between the data writing stage t81 and the light-emitting stage f. It should be noted that, in some examples, only the refresh frame F1 includes the second bias stage p2. In other examples, the hold frame F2 may also include the second bias stage p2, which is not limited by the embodiments of the present application.
Combining
Specifically, in the first bias stage p1, the data writing module 103 is turned on in response to the turn-on level output by the second scan signal terminal Scn2, and the first bias signal provided by the data signal terminal data is transmitted to the first terminal a or the second terminal b of the driving module 101 through the turned-on data writing module 103. Thus, the driving module 101 is in the OBS state, thereby realizing the adjustment of the threshold voltage of the driving module 101. In the data writing stage t81, the data writing module 103 is turned on in response to the turn-on level output by the second scan signal terminal Scn2, and the data signal provided by the data signal terminal data is transmitted to the first terminal a or the second terminal b of the driving module 101 through the turned-on data writing module 103.
It should be noted that the voltage value of the first bias signal may be the same as or different from the voltage value of the data signal, which is not limited by the embodiments of this application.
Thus, by increasing the turn-on duration of the data writing module 103 of the first bias stage p1 in the hold frame F2, and/or increasing the time interval T1 between the turn-on start moment of the data writing module 103 in the hold frame F2 and the light-emitting stage in the hold frame F2, the time period that the driving module is in the OBS state in the hold frame F2 may be increased. Therefore, the difference between the time period that the driving module is in the OBS state in the hold frame F2 and the time period that the driving module is in the OBS state in the refresh frame F1 may be improved. Further, the difference between the threshold voltage of the driving module in the hold frame F2 and the threshold voltage of the driving module in the refresh frame F1 may be improved, the difference between the brightness of the refresh frame F1 and the brightness of the hold frame F2 may be reduced, and the flashing problem may be improved.
In the hold frame F2, the data writing module turn-on stage t91 may be located after the first bias stage p1, or the turn-on moment of the data writing module turn-on stage t91 is the same as the turn-on moment of the first bias stage p1. That is, in the first bias stage p1, it can be that only the first bias module 102 is turned on, and the driving module 101 is placed in the OBS state by the first bias signal, thereby realizing the adjustment of the threshold voltage Vth of the driving module 101. Further, in the first bias stage p1, it can be that both the first bias module 102 and the data writing module 103 are turned on, and the driving module 101 is placed in the OBS state by both the first bias signal and the data signal, thereby realizing the adjustment of the threshold voltage Vth of the driving module 101.
Continuing referring to
Since both the first bias signal and the data signal are written to the first terminal or the second terminal of the driving module 101, the data writing stage t81 is provided after the first bias stage p1. Therefore, when writing the data signal, the data signal can be prevented from being interfered by the first bias signal, thereby ensuring that an accurate data signal is written to the driving module 101.
Further, either in the refresh frame F1 or in the hold frame F2, the turn-on pulses k in the first bias signal are located before the data writing module being turned on. In this way, the first bias signal can be kept at a stable frequency, and can be easily achieved by the driving IC.
As shown in
The pixel circuit 10 may also include a threshold compensation module 104, a control terminal of the threshold compensation module 104 is electrically connected to a third scan signal terminal Scn3, a first terminal of the threshold compensation module 104 is electrically connected to the first node N1, and a second terminal of the threshold compensation module 104 is electrically connected to the third node N3. The threshold compensation module 104 may be turned on under a control of a third scan signal provided by the third scan signal terminal Scn3, and the threshold compensation module 104 may be configured to connect the control terminal of the driving module 101 and the second terminal of the driving module 101. For example, in the data writing stage, the threshold compensation module 104 may be turned on to connect the control terminal of the driving module 101 with the second terminal of the driving module 101, thereby compensating for the threshold voltage of the driving module 101 together with the data writing module 103.
The pixel circuit 10 may also include a first reset module 105, a control terminal of the first reset module 105 is electrically connected to a fourth scan signal terminal Scn4, a first terminal of the first reset module 105 is electrically connected to a first initialization signal terminal Vref1, and a second terminal of the first reset module 105 is electrically connected to the first node N1. The first reset module 105 may be turned on under a control of a fourth scan signal provided by the fourth scan signal terminal Scn4, and may transmit a first initialization signal provided by the first initialization signal terminal Vref1 to the first node N1, so as to reset the first node N1.
In the embodiments of the present application, in addition to increasing the turn-on duration of the first bias module in the hold frame and/or increasing the time interval between the turn-on start moment of the first bias module in the hold frame and the light-emitting stage in the hold frame, the time period that the driving module is in the on-bias state in the refresh frame may be reduced by at least partially overlapping the turn-on stage of the first bias module in the refresh frame with other bias stages in the refresh frame. Therefore, the difference between the threshold voltage of the driving module in the hold frame and the threshold voltage of the driving module in the refresh frame may be improved, and the flashing problem may be improved. The details are shown in
Meanwhile, the third bias stage p3 at least partially overlaps with the first bias stage p1. Therefore, in a partial stage of the first bias stage p1 overlapping with the third bias stage p3, the first bias module 102 is also turned on, and the first bias signal is transmitted to the first terminal or the second terminal of the driving module 101.
Thus, in the third bias stage p3, since the threshold compensation module 104 is turned on to connect the control terminal of the driving module 101 and the second terminal of the driving module 101, the potential of the second terminal of the driving module 101 may be equal to the potential of the control terminal of the driving module 101. Under a control of both the first bias signal and the second bias signal, the driving module 101 is in the OBS state, thereby achieving the adjustment of the threshold voltage Vth of the driving module 101. For different pixel circuits, the voltage value of the second bias signal can vary. Therefore, the second bias signal of a corresponding voltage value can be matched according to the bias degree of the threshold voltage of the driving module 101, thereby achieving a precise adjustment of the threshold voltage of the driving module 101.
In the embodiments of the present application, by adding the first bias stage p1 in the hold frame F2, the time period that the driving module is in the OBS state in the hold frame may be increased. Therefore, the difference between the time period that the driving module is in the OBS state in the hold frame and the time period that the driving module is in the OBS state in the refresh frame may be improved, and the flashing problem may be improved. However, the inventor of the present application considers that if only adding the first bias frame stage p1 in the hold frame F2, it will inevitably cause the difference between the Scn1 signal in the refresh frame F1 and the Scn1 signal in the hold frame F2, which increases the complexity of the Scn1 signal, and is not convenient for the output adjustment of the driving IC. Therefore, on the basis of adding the first bias stage p1 in the hold frame F2, the first bias stage p1 is also added in the refresh frame F1. Therefore, the Scn1 signal maintains a stable frequency in the refresh frame F1 and the hold frame F2, which reduces the complexity of the Scn1 signal, and facilitates the implementation of the drive IC. Further, by overlapping the first bias stage p1 with the third bias stage p3 in the refresh frame F1, the third bias stage p3 covers the first bias stage p1. Therefore, even if the first bias stage p1 is added in the refresh frame F1, since the first bias stage p1 overlaps with the third bias stage p3, the time period that the driving module is in the OBS state in the refresh frame F1 is not additionally increased. That is, the time period that the driving module is in the OBS state in the refresh frame is reduced, which is beneficial to reduce the difference between the time period that the driving module is in the OBS state in the hold frame and the time period that the driving module is in the OBS state in the refresh frame. Moreover, in a stage that the first bias stage p1 overlaps with the third bias stage p3, the first bias module 102, the threshold compensation module 104 and the first reset module 105 are all turned on. Under a control of both the first bias signal and the second bias signal, the adjustment of the threshold voltage Vth of the driving module 101 is achieved, and a good adjustment effect is achieved.
Further, the OBS time difference between the hold frame F2 and the refresh frame F1 is that the refresh frame F1 has the third bias stage p3 and the hold frame F2 do not have the third bias stage p3. With such a design, it can be ensured that the time position of the first bias stage p1 in the hold frame F2 is consistent with the time position of the third bias stage p3 in the refresh frame F1 (i.e., the overlapped stage of the turn-on level of the Scn3 and the turn-on level of the Scn4), and the OBS time difference between the hold frame F2 and the refresh frame F1 is reduced.
Optionally, the turn-on stage of the first bias module 102 in the hold frame F2 at least partially not overlaps with other bias stages in the hold frame F2.
Of course, in other alternative embodiments of the present application, the turn-on stage of the first bias module 102 in the hold frame F2 at least partially overlaps with the other bias stages in the hold frame F2. However, that overlapped duration is less than the duration during which the turn-on stage of the first bias module 102 in the refresh frame F1 overlaps with the other bias stages in the refresh frame F1. That is, the duration during which the effective bias signal of the first bias module 102 independently affects the driving module in the hold frame F2 is greater than that in the refresh frame F1.
Optionally, the bias signal of the other bias stages is also applied to the node where the first bias module is connected to the pixel circuit. Alternatively, other modules in the circuit to which the other bias stages are directed at least partially consistent with the module to which the first bias module is directed.
Combining
In the third bias stage p3, the threshold compensation module 104 is turned on under a control of the third scan signal provided by the third scan signal terminal Scn3. The first reset module 105 is turned on under a control of the fourth scan signal provided by the fourth scan signal terminal Scn4. The second bias signal output by the first initialization signal terminal Vref1 is transmitted to the control terminal of the driving module 101 and the second terminal of the driving module 101. Similar to the first bias signal, the second bias signal may be configured to adjust the bias state of the driving module 101. That is, the driving module 101 may be in the OBS state, thereby achieving the adjustment of the threshold voltage Vth of the driving module 101.
Thus, under a control of the second bias signal, the driving module 101 is in the OBS state, thereby achieving the adjustment of the threshold voltage Vth of the driving module 101. For different pixel circuits, the voltage value of the second bias signal can vary. Therefore, the second bias signal of a corresponding voltage value can be matched according to the bias degree of the threshold voltage of the driving module 101, thereby achieving a precise adjustment of the threshold voltage of the driving module 101.
As shown in
Specifically, the control terminal of the threshold compensation module 104 is electrically connected to the third scan signal terminal Scn3, the first terminal of the threshold compensation module 104 is electrically connected to the first node N1, and the second terminal of the threshold compensation module 104 is electrically connected to the third node N3. The threshold compensation module 104 may be turned on under a control of the third scan signal provided by the third scan signal terminal Scn3, and the threshold compensation module 104 may be configured to connect the control terminal of the driving module 101 and the second terminal of the driving module 101. The control terminal of the first reset module 105 is electrically connected to the fourth scan signal terminal Scn4, the first terminal of the first reset module 105 is electrically connected to the first initialization signal terminal Vref1, and the second terminal of the first reset module 105 is electrically connected to the third node N3.
In the third bias stage p3, the threshold compensation module 104 is turned on under a control of the third scan signal provided by the third scan signal terminal Scn3. The first reset module 105 is turned on under a control of the fourth scan signal provided by the fourth scan signal terminal Scn4. The second bias signal output by the first initialization signal terminal Vref1 is transmitted to the control terminal of the driving module 101 and the second terminal of the driving module 101. Therefore, the driving module 101 may be in the OBS state, thereby achieving the adjustment of the threshold voltage Vth of the driving module 101.
It should be noted that, in some embodiments, in the refresh frame F1, the initialization stage t41 and the third bias stage p3 can overlap with each other, that is, the initialization stage t41 and the third bias stage p3 can be regarded as a same stage. Therefore, while the reset of the first node N1 is achieved, the driving module 101 is in the OBS state, thereby achieving the adjustment of the threshold voltage Vth of the driving module 101.
Specifically, for example, the first reset module 105 is turned on under a condition that the fourth scan signal terminal Scn4 outputs a low level. In the first bias stage p1, the first reset module 105 is turned on under a control of the fourth scan signal provided by the fourth scan signal terminal Scn4, and the first bias signal output by the first initialization signal terminal Vref1 is transmitted to the control terminal of the driving module 101 and the second terminal of the driving module 101. Therefore, the driving module 101 is in the OBS state, thereby achieving the adjustment of the threshold voltage Vth of the driving module 101.
For example, the threshold compensation module 104 may be turned on under a condition that the third scan signal terminal Scn3 outputs a high level, and the first reset module 105 may be turned on under a condition that the fourth scan signal terminal Scn4 outputs a low level. In the initialization stage t41 of the refresh frame F1, the threshold compensation module 104 is turned on under a control of the third scan signal provided by the third scan signal terminal Scn3, and the first reset module 105 is turned on under a control of the fourth scan signal provided by the fourth scan signal terminal Scn4. The first initialization signal output by the first initialization signal terminal Vref1 is transmitted to the control terminal (i.e., the first node N1) of the driving module 101 through the turned-on first reset module 105 and the turn-on threshold compensation module 104 in sequence, thereby achieving reset of the first node N1. Here, the voltage value of the first initialization signal may be the same as or different from the voltage value of the first bias signal, which is not limited by the embodiments of the present application.
Thus, since the first bias module 102 is reused as the first reset module 105, the number of electronic devices in the pixel circuit can be reduced, which is beneficial to save the wiring space and reduce the production cost.
Thus, before the data writing stage t81, the threshold voltage Vth of the driving module 101 is adjusted by the second bias signal. Therefore, the shift degree of the Id-Vg curve of the driving module is reduced. Further, the display uniformity of the display panel is guaranteed, and the brightness of the first frame when switching pictures is increased.
Further, combining
Thus, since the time interval T3 is equal to the time interval T4, the time period that the driving module is in the OBS state in the hold frame F2 is equal to the time period that the driving module is in the OBS state in the refresh frame F1. Therefore, there is almost no difference between the threshold voltage of the driving module in the hold frame F2 and the threshold voltage of the driving module in the refresh frame F1. Thus, the difference between the brightness of the refresh frame F1 and the brightness of the hold frame F2 may be small, and the flashing problem may be improved
Thus, under a control of both the second bias signal and the third bias signal, the driving module 101 is in the OBS state, thereby achieving the adjustment of the threshold voltage Vth of the driving module 101.
The pixel circuit 10 may further includes a second reset module 108, a control terminal of the second reset module 108 is electrically connected to a sixth scan signal terminal Scn6, a first terminal of the second reset module 108 is electrically connected to a second initialization signal terminal Vref2, and a second terminal of the second reset module 108 is electrically connected to the first electrode of the light-emitting element D.
The second reset module 108 can also be turned on under a control of the sixth scan signal provided by the sixth scan signal terminal Scn6 in any stage (for example, the data writing stage) prior to the light-emitting stage f. Further, the second initialization signal output by the second initialization signal terminal Vref2 is transmitted to the first electrode of the light-emitting element D, thereby resetting the first electrode of the light-emitting element D. Here, the voltage value of the second initialization signal may be the same as or different from the voltage value of the second bias signal.
Thus, by reusing the second reset module 108 to adjust the threshold voltage Vth of the driving module 101, the number of electronic devices in the pixel circuit can be reduced, which is beneficial to save the wiring space and reduce the production cost.
In the embodiments of the present application, the pixel circuit may be applied in a display panel, and a picture refresh cycle H of the display panel may include a plurality of frames. For example, when the display panel displays at a low refresh rate, a picture refresh cycle H may include one refresh frame F1 and at least two hold frames F2. Here, the number of the hold frames F2 in a picture refresh cycle H can be flexibly adjusted according to the actual situation, which is not limited by the embodiments of the present application.
Thus, the time period that the driving module is in the OBS state may be the same or similar among the plurality of hold frames F2 in the same picture refresh cycle. Therefore, the threshold voltage of the driving module may be the same or similar among the plurality of hold frames F2 in the same picture refresh cycle. Further, the brightness of the plurality of hold frames F2 in the same picture refresh cycle may be the same or similar, so that the brightness-flashing problem between different hold frames F2 may be further improved.
a number of pulses of the first scan signal in the ith hold frame F2 is equal to a number of pulses of the first scan signal in the (i+1)th hold frame F2. Specifically, the number of pulses k of the first scan signal in the ith hold frame F2 may be greater than the number of pulses k of the first scan signal in the refresh frame F1, the number of pulses k of the first scan signal in the (i+1)th hold frame F2 may be greater than the number of pulses k of the first scan signal in the refresh frame F1, and the number of pulses k of the first scan signal in the ith hold frame F2 may be equal to the number of pulses k of the first scan signal in the (i+1)th hold frame F2.
a width of the pulse of the first scan signal in the ith hold frame F2 is equal to a width of the pulse of the first scan signal in the (i+1)th hold frame F2. For example, the width of each pulse k in the ith hold frame F2 and the (i+1)th hold frame F2 is Δt1, and the width of each pulse k in the refresh frame F1 is Δt2, where Δt1>Δt2.
Thus, the turn-on duration of the first bias module in the hold frame F2 is greater than the turn-on duration of the first bias module in the refresh frame F1. Therefore, the difference between the time period that the driving module is in the OBS state in the hold frame F2 and the time period that the driving module is in the OBS state in the refresh frame F1 may be improved. Further, the difference between the threshold voltage of the driving module in the hold frame F2 and the threshold voltage of the driving module in the refresh frame F1 may be improved, the difference between the brightness of the refresh frame F1 and the brightness of the hold frame F2 may be reduced, and the flashing problem may be improved. Meanwhile, the time period that the driving module is in the OBS state may be the same or similar among the plurality of hold frames F2 in the same picture refresh cycle. Therefore, the threshold voltage of the driving module may be the same or similar among the plurality of hold frames F2 in the same picture refresh cycle. Further, the brightness of the plurality of hold frames F2 in the same picture refresh cycle may be the same or similar, so that the brightness-flashing problem between different hold frames F2 may be further improved.
For convenience, the pixel circuit of the embodiments of the present application will be illustrated below in combination with some specific application embodiments.
The control terminal of the driving module 101 may be electrically connected to a first node N1, the first terminal of the driving module 101 may be electrically connected to a second node N2, and the second terminal of the driving module 101 may be electrically connected to a third node N3.
The control terminal of the data writing module 103 is electrically connected to the second scan signal terminal Scn2, the first terminal of the data writing module 103 is electrically connected to the data signal terminal data, and the second terminal of the data writing module 103 is electrically connected to the first terminal or the second terminal of the driving module 101.
The control terminal of the threshold compensation module 104 is electrically connected to the third scan signal terminal Scn3, the first terminal of the threshold compensation module 104 is electrically connected to the first node N1, and the second terminal of the threshold compensation module 104 is electrically connected to the third node N3.
The control terminal of the first reset module 105 is electrically connected to the fourth scan signal terminal Scn4, the first terminal of the first reset module 105 is electrically connected to the first initialization signal terminal Vref1, and the second terminal of the first reset module 105 is electrically connected to the first node N1.
The control terminal of the first light-emitting control module 107 is electrically connected to the light-emitting control signal line EM, the first terminal of the first light-emitting control module 107 is electrically connected to the second terminal of the driving module 101, and the second terminal of the first light-emitting control module 107 is electrically connected to the first electrode of the light-emitting element D.
The control terminal of the second reset module 108 is electrically connected to the sixth scan signal terminal Scn6, the first terminal of the second reset module 108 is electrically connected to the second initialization signal terminal Vref2, and the second terminal of the second reset module 108 is electrically connected to the first electrode of the light-emitting element D.
The control terminal of the second light-emitting control module 109 is electrically connected to the light-emitting control signal line EM, the first terminal of the second light-emitting control module 109 is electrically connected to the first power signal terminal PVDD, and the second terminal of the second light-emitting control module 109 is electrically connected to the second node N2.
The first terminal of the storage module 110 is electrically connected to the first power signal terminal PVDD, and the second terminal of the storage module 110 is electrically connected to the first node N1.
In some embodiments, the second scan signal terminal Scn2 may be reused as the sixth scan signal terminal Scn6.
In the initialization stage t41 of the refresh frame F1, the threshold compensation module 104 is turned off under a control of the third scan signal provided by the third scan signal terminal Scn3. The first reset module 105 is turned on under a control of the fourth scan signal provided by the fourth scan signal terminal Scn4. The first initialization signal output by the first initialization signal terminal Vref1 is transmitted to the control terminal (i.e., the first node N1) of the driving module 101, thereby achieving reset of the first node N1.
In the third bias stage p3 of the refresh frame F1, the threshold compensation module 104 is turned on under a control of the third scan signal provided by the third scan signal terminal Scn3. The first reset module 105 is turned on under a control of the fourth scan signal provided by the fourth scan signal terminal Scn4. The second bias signal output by the first initialization signal terminal Vref1 is transmitted to the control terminal of the driving module 101 and the second terminal of the driving module 101. Therefore, the driving module 101 may be in the OBS state, thereby achieving the adjustment of the threshold voltage Vth of the driving module 101.
In the data writing stage t81 of the refresh frame F1, the data writing module 103 is turned on in response to the turn-on level output by the second scan signal terminal Scn2, and the data signal provided by the data signal terminal data is transmitted to the first terminal of the driving module 101 through the turned-on data writing module 103. Under a control of the third scan signal provided by the third scan signal terminal Scn3, the threshold compensation module 104 is turned on to connect the control terminal of the driving module 101 with the second terminal of the driving module 101, thereby compensating for the threshold voltage of the driving module 101 together with the data writing module 103.
In the second bias stage p2 of the refresh frame F1, the data writing module 103 is turned on in response to the turn-on level output by the second scan signal terminal Scn2. The threshold compensation module 104 is turned off under a control of the third scan signal provided by the third scan signal terminal Scn3. The first bias signal provided by the data signal terminal data is transmitted to the first terminal of the driving module 101 through the turned-on data writing module 103. Since the first node N1 is at a low level, the driving module 101 is turned on, and the first bias signal provided by the data signal terminal data is transmitted to the second terminal of the driving module 101 through the turned-on driving module 101. Therefore, the potential of the second terminal of the driving module 101 is greater than or equal to the potential of the control terminal of the driving module 101, thereby further adjusting the threshold voltage Vth of the driving module by the first bias signal. Therefore, the characteristic curve of the driving module 101 is restored to the normal threshold voltage corresponding to when the data signal is written as soon as possible, thereby effectively avoiding the change of the light-emitting brightness at the beginning of the light-emitting stage.
In the light-emitting stage f of the refresh frame F1, the first light-emitting control module 107 is turned on under a control of the light-emitting control signal provided by the light-emitting control signal terminal EM, the second light-emitting control module 109 is turned on under a control of the light-emitting control signal provided by the light-emitting control signal terminal EM, the driving module 101 is turned on under a control of the first node N1, and the light-emitting element D emits light.
In the first bias stage p1 of the hold frame F2, the data writing module 103 is turned on in response to the turn-on level output by the second scan signal terminal Scn2. The first bias signal provided by the data signal terminal data is transmitted to the first terminal of the driving module 101 through the turned-on data writing module 103. Since the first node N1 is at a low level, the driving module 101 is turned on, and the first bias signal provided by the data signal terminal data is transmitted to the second terminal of the driving module 101 through the turned-on driving module 101. Therefore, the potential of the second terminal of the driving module 101 is greater than or equal to the potential of the control terminal of the driving module 101, thereby adjusting the threshold voltage Vth of the driving module by the first bias signal.
In the second bias stage p2 of the hold frame F2, the data writing module 103 is turned on in response to the turn-on level output by the second scan signal terminal Scn2. The first bias signal provided by the data signal terminal data is transmitted to the first terminal of the driving module 101 through the turned-on data writing module 103. Since the first node N1 is at a low level, the driving module 101 is turned on, and the first bias signal provided by the data signal terminal data is transmitted to the second terminal of the driving module 101 through the turned-on driving module 101. Therefore, the potential of the second terminal of the driving module 101 is greater than or equal to the potential of the control terminal of the driving module 101, thereby adjusting the threshold voltage Vth of the driving module by the first bias signal.
In the light-emitting stage f of the hold frame F2, the first light-emitting control module 107 is turned on under a control of the light-emitting control signal provided by the light-emitting control signal terminal EM, the second light-emitting control module 109 is turned on under a control of the light-emitting control signal provided by the light-emitting control signal terminal EM, the driving module 101 is turned on under a control of the first node N1, and the light-emitting element D emits light.
It should be noted that although
Continuing referring to
The gate of the first transistor M1 is electrically connected to the first node N1, the first electrode of the first transistor M1 is electrically connected to the second node N2, and the second electrode of the first transistor M1 is electrically connected to the third node N3.
The gate of the second transistor M2 is electrically connected to the second scan signal terminal Scn2, the first electrode of the second transistor M2 is electrically connected to the data signal terminal data, and the second electrode of the second transistor M2 is electrically connected to the second node N2 or the third node N3;
The gate of the third transistor M3 is electrically connected to the third scan signal terminal Scn3, the first electrode of the third transistor M3 is electrically connected to the first node N1, and the second electrode of the third transistor M3 is electrically connected to the third node N3;
The gate of the fourth transistor M4 is electrically connected to the fourth scan signal terminal Scn4, the first electrode of the fourth transistor M4 is electrically connected to the first initialization signal terminal Vref1, and the second electrode of the fourth transistor M4 is electrically connected to the first node N1;
The gate of the fifth transistor M5 is electrically connected to the light-emitting control signal line EM, the first electrode of the fifth transistor M5 is electrically connected to the third node N3, and the second electrode of the fifth transistor M5 is electrically connected to the first electrode of the light-emitting element D;
The gate of the sixth transistor M6 is electrically connected to the light-emitting control signal line EM, the first electrode of the sixth transistor M6 is electrically connected to the first power signal terminal PVDD, and the second electrode of the sixth transistor M6 is electrically connected to the second node N2;
The gate of the seventh transistor M7 is electrically connected to the sixth scan signal terminal Scn6, the first electrode of the seventh transistor M7 is electrically connected to the second initialization signal terminal Vref2, and the second electrode of the seventh transistor M7 is electrically connected to the first electrode of the light-emitting element D;
The first plate of the storage capacitor Cst is electrically connected to the first power signal terminal PVDD, and the second plate of the storage capacitor Cst is electrically connected to the first node N1.
In some embodiments, the third transistor M3 and the fourth transistor M4 may be N-type transistors, and the first transistor M1, the second transistor M2, the fifth transistor M5, the sixth transistor M6 and the seventh transistor M7 may be P-type transistors.
In some embodiments, the third transistor M3 and the fourth transistor M4 may be oxide thin film transistors, such as indium gallium zinc oxide thin film transistors. The first transistor M1, the second transistor M2, the fifth transistor M5, the sixth transistor M6 and the seventh transistor M7 may be low-temperature polycrystalline silicon thin film transistors.
Further, the pixel circuit 10 may also include a driving module 101, a data writing module 103, a threshold compensation module 104, a first reset module 105, a first light-emitting control module 107, a second reset module 108, a second light-emitting control module 109, and a storage module 110. The specific structures and connections of these modules are the same as the embodiment shown in
In the initialization stage t41 of the refresh frame F1, the threshold compensation module 104 is turned off under a control of the third scan signal provided by the third scan signal terminal Scn3. The first reset module 105 is turned on under a control of the fourth scan signal provided by the fourth scan signal terminal Scn4. The first initialization signal output by the first initialization signal terminal Vref1 is transmitted to the control terminal (i.e., the first node N1) of the driving module 101, thereby achieving reset of the first node N1.
In the third bias stage p3 of the refresh frame F1, the threshold compensation module 104 is turned on under a control of the third scan signal provided by the third scan signal terminal Scn3. The first reset module 105 is turned on under a control of the fourth scan signal provided by the fourth scan signal terminal Scn4. The first bias module 102 is turned on under a control of the fifth scan signal provided by the first scan signal terminal Scn1. The second bias signal output by the first initialization signal terminal Vref1 is transmitted to the control terminal of the driving module 101 and the second terminal of the driving module 101. The first bias signal output by the first bias signal terminal V1 is transmitted to the first terminal or the second terminal of the driving module 101. Therefore, the driving module 101 may be in the OBS state, thereby achieving the adjustment of the threshold voltage Vth of the driving module 101.
In the data writing stage t81 of the refresh frame F1, the data writing module 103 is turned on in response to the turn-on level output by the second scan signal terminal Scn2, and the data signal provided by the data signal terminal data is transmitted to the first terminal of the driving module 101 through the turned-on data writing module 103. Under a control of the third scan signal provided by the third scan signal terminal Scn3, the threshold compensation module 104 is turned on to connect the control terminal of the driving module 101 with the second terminal of the driving module 101, thereby compensating for the threshold voltage of the driving module 101 together with the data writing module 103.
In the second bias stage p2 of the refresh frame F1, the data writing module 103 is turned on in response to the turn-on level output by the second scan signal terminal Scn2. The threshold compensation module 104 is turned off under a control of the third scan signal provided by the third scan signal terminal Scn3. The first bias signal provided by the data signal terminal data is transmitted to the first terminal of the driving module 101 through the turned-on data writing module 103. Since the first node N1 is at a low level, the driving module 101 is turned on, and the first bias signal provided by the data signal terminal data is transmitted to the second terminal of the driving module 101 through the turned-on driving module 101. Therefore, the potential of the second terminal of the driving module 101 is greater than or equal to the potential of the control terminal of the driving module 101, thereby further adjusting the threshold voltage Vth of the driving module by the first bias signal. Therefore, the characteristic curve of the driving module 101 is restored to the normal threshold voltage corresponding to when the data signal is written as soon as possible, thereby effectively avoiding the change of the light-emitting brightness at the beginning of the light-emitting stage.
Alternatively, in the second bias stage p2 of the refresh frame F1, the first bias module 102 is turned on under a control of the fifth scan signal provided by the first scan signal terminal Scn1, and the first bias signal output by the first bias signal terminal V1 is transmitted to the first terminal or the second terminal of the driving module 101. Therefore, the driving module 101 may be in the OBS state, thereby achieving the adjustment of the threshold voltage Vth of the driving module 101.
In the light-emitting stage f of the refresh frame F1, the first light-emitting control module 107 is turned on under a control of the light-emitting control signal provided by the light-emitting control signal terminal EM, the second light-emitting control module 109 is turned on under a control of the light-emitting control signal provided by the light-emitting control signal terminal EM, the driving module 101 is turned on under a control of the first node N1, and the light-emitting element D emits light.
In the first bias stage p1 and the second bias stage p1 of the hold frame F2, the data writing module 103 is turned on in response to the turn-on level output by the second scan signal terminal Scn2. The first bias signal provided by the data signal terminal data is transmitted to the first terminal of the driving module 101 through the turned-on data writing module 103. Since the first node N1 is at a low level, the driving module 101 is turned on, and the first bias signal provided by the data signal terminal data is transmitted to the second terminal of the driving module 101 through the turned-on driving module 101. Therefore, the potential of the second terminal of the driving module 101 is greater than or equal to the potential of the control terminal of the driving module 101, thereby adjusting the threshold voltage Vth of the driving module by the first bias signal.
Alternatively, in the first bias stage p1 and the second bias stage p1 of the hold frame F2, the first bias module 102 is turned on under a control of the fifth scan signal provided by the first scan signal terminal Scn1, and the first bias signal output by the first bias signal terminal V1 is transmitted to the first terminal or the second terminal of the driving module 101. Therefore, the driving module 101 may be in the OBS state, thereby achieving the adjustment of the threshold voltage Vth of the driving module 101.
In the light-emitting stage f of the hold frame F2, the first light-emitting control module 107 is turned on under a control of the light-emitting control signal provided by the light-emitting control signal terminal EM, the second light-emitting control module 109 is turned on under a control of the light-emitting control signal provided by the light-emitting control signal terminal EM, the driving module 101 is turned on under a control of the first node N1, and the light-emitting element D emits light.
It should be noted that although
Continuing referring to
The gate of the first transistor M1 is electrically connected to the first node N1, the first electrode of the first transistor M1 is electrically connected to the second node N2, and the second electrode of the first transistor M1 is electrically connected to the third node N3.
The gate of the second transistor M2 is electrically connected to the second scan signal terminal Scn2, the first electrode of the second transistor M2 is electrically connected to the data signal terminal data, and the second electrode of the second transistor M2 is electrically connected to the second node N2 or the third node N3;
The gate of the third transistor M3 is electrically connected to the third scan signal terminal Scn3, the first electrode of the third transistor M3 is electrically connected to the first node N1, and the second electrode of the third transistor M3 is electrically connected to the third node N3;
The gate of the fourth transistor M4 is electrically connected to the fourth scan signal terminal Scn4, the first electrode of the fourth transistor M4 is electrically connected to the first initialization signal terminal Vref1, and the second electrode of the fourth transistor M4 is electrically connected to the first node N1;
The gate of the fifth transistor M5 is electrically connected to the light-emitting control signal line EM, the first electrode of the fifth transistor M5 is electrically connected to the third node N3, and the second electrode of the fifth transistor M5 is electrically connected to the first electrode of the light-emitting element D;
The gate of the sixth transistor M6 is electrically connected to the light-emitting control signal line EM, the first electrode of the sixth transistor M6 is electrically connected to the first power signal terminal PVDD, and the second electrode of the sixth transistor M6 is electrically connected to the second node N2;
The gate of the seventh transistor M7 is electrically connected to the sixth scan signal terminal Scn6, the first electrode of the seventh transistor M7 is electrically connected to the second initialization signal terminal Vref2, and the second electrode of the seventh transistor M7 is electrically connected to the first electrode of the light-emitting element D;
The gate of the eighth transistor M8 is electrically connected to the first scan signal terminal Scn1, the first electrode of the eighth transistor M8 is electrically connected to the first bias signal terminal V1, and the second electrode of the eighth transistor M8 is electrically connected to the second node N2 or the third node N3;
The first plate of the storage capacitor Cst is electrically connected to the first power signal terminal PVDD, and the second plate of the storage capacitor Cst is electrically connected to the first node N1.
Based on the same technical concept as the pixel circuit 10 provided by the above embodiments, accordingly, the embodiments of the present application also provide a driving method of a pixel circuit, and the driving method of the pixel circuit can be applied to the pixel circuit 10 provided by the above embodiments.
As shown in
A light-emitting cycle of the light-emitting element includes a refresh frame F1 or a hold frame F2. A control terminal of the driving module is refreshed in the refresh frame F1, and the control terminal of the driving module is not refreshed in the hold frame F2. Each of the refresh frame F1 and the hold frame F2 includes a first stage and a second stage, the first stage is located before the second stage, the first stage includes one or more bias stages, and the second stage includes a light-emitting stage of the light-emitting element.
S101: in the bias stages, controlling the first bias module to be turned on, and transmitting the first bias signal to the first terminal or the second terminal of the driving module.
Here, a turn-on duration of the first bias module in the hold frame F2 is greater than a turn-on duration of the first bias module in the refresh frame F1; and/or a time interval between a turn-on start moment of the first bias module in the hold frame F2 and the light-emitting stage in the hold frame F2 is greater than a time interval between a turn-on start moment of the first bias module in the refresh frame F1 and the light-emitting stage in the refresh frame F1; and/or a turn-on stage of the first bias module in the refresh frame at least partially overlaps with other bias stages in the refresh frame.
According to the driving method of the pixel circuit provided by the embodiments of the present application, by increasing the turn-on duration of the first bias module in the hold frame, and/or increasing the time interval between the turn-on start moment of the first bias module in the hold frame and the light-emitting stage in the hold frame, and/or at least partially overlapping the turn-on stage of the first bias module in the refresh frame with other bias stages in the refresh frame, the time period that the driving module is in the on-bias state in the hold frame may be increased and/or the time period that the driving module is in the on-bias state in the refresh frame may be reduced. Further, the difference between the threshold voltage of the driving module in the hold frame and the threshold voltage of the driving module in the refresh frame may be improved, the difference between the brightness of the refresh frame and the brightness of the hold frame may be reduced, and the flashing problem may be improved.
In some embodiments, a control terminal of the first bias module is electrically connected to a first scan signal terminal, a first terminal of the first bias module is electrically connected to a first bias signal terminal, and a second terminal of the first bias module is electrically connected to the first terminal or the second terminal of the driving module. Under a control of a first scan signal provided by the first scan signal terminal, the first bias module transmits the first bias signal provided by the first bias signal terminal to the first terminal or the second terminal of the driving module. In the refresh frame and the hold frame, the bias stages include a first bias stage.
S101 may specifically include: in the first bias stage, controlling the first bias module to be turned on, and transmitting the first bias signal to the first terminal or the second terminal of the driving module.
In some embodiments, the first stage of the refresh frame further includes a data writing stage, and at least the bias stages of the refresh frame further include a second bias stage, the second bias stage is located between the data writing stage and the light-emitting stage.
S102: in the second bias stage, controlling the first bias module to be turned on, and transmitting the first bias signal to the first terminal or the second terminal of the driving module.
In some embodiments, the pixel circuit further includes a data writing module, a control terminal of the data writing module is electrically connected to a second scan signal terminal, a first terminal of the data writing module is electrically connected to a data signal terminal, and a second terminal of the data writing module is electrically connected to the first terminal or the second terminal of the driving module. The first bias module is reused as the data writing module, the first scan signal terminal is reused as the second scan signal terminal, and the first bias signal terminal is reused as the data signal terminal.
In some embodiments, the bias stages of the refresh frame further include a third bias stage, and the third bias stage at least partially overlaps with the first bias stage. The control terminal of the driving module is electrically connected to a first node, the first terminal of the driving module is electrically connected to a second node, and the second terminal of the driving module is electrically connected to a third node. The pixel circuit further includes a threshold compensation module, a control terminal of the threshold compensation module is electrically connected to a third scan signal terminal, a first terminal of the threshold compensation module is electrically connected to the first node, and a second terminal of the threshold compensation module is electrically connected to the third node. Under a control of a third scan signal provided by the third scan signal terminal, the threshold compensation module is configured to connect the control terminal of the driving module and the second terminal of the driving module. The pixel circuit further includes a first reset module, a control terminal of the first reset module is electrically connected to a fourth scan signal terminal, a first terminal of the first reset module is electrically connected to a first initialization signal terminal, and a second terminal of the first reset module is electrically connected to the first node or the third node.
S103: in the third bias stage, causing the threshold compensation module to be turned on under a control of the third scan signal provided by the third scan signal terminal, causing the first reset module to be turned on under a control of a fourth scan signal provided by the fourth scan signal terminal, and transmitting a second bias signal output by the first initialization signal terminal to the control terminal of the driving module and the second terminal of the driving module, wherein the second bias signal is configured to adjust the bias state of the driving module.
In some embodiments, the control terminal of the driving module is electrically connected to a first node, the first terminal of the driving module is electrically connected to a second node, and the second terminal of the driving module is electrically connected to a third node. The pixel circuit further includes a threshold compensation module, a control terminal of the threshold compensation module is electrically connected to a third scan signal terminal, a first terminal of the threshold compensation module is electrically connected to the first node, and a second terminal of the threshold compensation module is electrically connected to the third node. Under a control of a third scan signal provided by the third scan signal terminal, the threshold compensation module is configured to connect the control terminal of the driving module and the second terminal of the driving module. The pixel circuit further includes a first reset module, a control terminal of the first reset module is electrically connected to a fourth scan signal terminal, a first terminal of the first reset module is electrically connected to a first initialization signal terminal, and a second terminal of the first reset module is electrically connected to the first node or the third node. The bias stages of the refresh frame further include a third bias stage, and the third bias stage is located before the first bias stage.
As shown in
S103: in the third bias stage, causing the threshold compensation module to be turned on under a control of the third scan signal provided by the third scan signal terminal, causing the first reset module to be turned on under a control of a fourth scan signal provided by the fourth scan signal terminal, and transmitting a second bias signal output by the first initialization signal terminal to the control terminal of the driving module and the second terminal of the driving module, wherein the second bias signal is configured to adjust the bias state of the driving module.
In some embodiments, the pixel circuit further includes a second bias module, a control terminal of the second bias module is electrically connected to a fifth scan signal terminal, a first terminal of the second bias module is electrically connected to a second bias signal terminal, and a second terminal of the second bias module is electrically connected to the first terminal or the second terminal of the driving module. The bias stages of the refresh frame further include a third bias stage, and the third bias stage is located before the first bias stage.
S103: in the third bias stage, causing the second bias module to be turned on under a control of a third scan signal provided by the fifth scan signal terminal, and transmitting a second bias signal output by the second bias signal terminal to the first terminal or the second terminal of the driving module, wherein the second bias signal is configured to adjust the bias state of the driving module.
It should be noted that the specific process of the above steps S101 to S103 is described in detail in the pixel circuit 10 provided by the above embodiments, and will not be described herein for the sake of simplicity. Moreover, for the sake of simplicity, some of the technical features of the driving method of the pixel circuit provided by the embodiments of the present application are not listed. However, it is easy to understand that the driving method of the pixel circuit provided by the embodiments of the present application has the same or corresponding technical features as the pixel circuit 10. That is, all of the technical features of the pixel circuit 10 provided by the above embodiments are applicable to the driving method of the pixel circuit provided by the embodiments of the present application.
The display panel 360 provided by the embodiments of the present application has the beneficial effects of the pixel circuit 10 provided by the embodiments of the present application. For details, please refer to the specific description of the pixel circuit 10 in the above embodiments, which will not be repeated here.
Based on the display panel 360 provided in the above embodiments, accordingly, the present application also provides a display device, including the display panel provided by the present application. Referring to
It should be understood that the specific structures of the pixel circuit and the display panel provided in the illustrated embodiments of the present application are only some examples, and are not intended to limit the present application. Further, in the case of not contradictory, the above embodiments provided in the present application may be combined with each other.
It should be clear that the present application is not limited to the specific configuration and processing described above and illustrated in figures. For the sake of simplicity, a detailed description of the known methods is omitted here. In the above embodiments, several specific steps are described and illustrated as examples. However, the method process of the present application is not limited to the specific steps described and shown, and after understanding the spirit of the present application, those skilled in the art can may make changes, modifications and additions, or may change the order of the steps.
The functional blocks shown in the structural views described above may be implemented as hardware, software, firmware, or a combination thereof. When implemented as hardware, it may be, for example, an electronic circuit, an application specific integrated circuit (ASIC), appropriate firmware, plugins, function cards, etc. When implemented as software, elements of the present application are programs or code segments for performing required tasks. The programs or code segments may be stored in a machine-readable medium, or transmitted on a transmission medium or a communication link through a data signal carried in a carrier wave. The “machine-readable medium” may include any medium that can store or transmit information. Examples of the machine-readable medium include an electronic circuit, a semiconductor memory device, a ROM, a flash memory, an erasable ROM (EROM), a floppy disk, a CD-ROM, an optical disk, a hard disk, a fiber optic medium, a radio frequency (RF) link, and so on. The code segments may be downloaded via a computer network such as the Internet, intranet, and so on.
It should also be noted that according to the exemplary embodiments described in the present application, some methods or systems are described based on a series of steps or apparatuses. However, the present application is not limited to the above order of the steps. That is, the steps may be executed in the order described in the embodiments or in orders different from that in the embodiments, or several steps may be executed simultaneously.
Aspects of the present application are described above with reference to flowcharts and/or block diagrams of methods, devices (systems) and machine program products according to embodiments of the present application. It will be understood that each block of the flowcharts and/or block diagrams, and combinations of blocks of the flowcharts and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, a special purpose computer, or other programmable data processing device to produce a machine, such that these instructions executed by the processor of the computer or other programmable data processing device can enable implementation of the functions/acts specified in one or more blocks of the flowcharts and/or block diagrams. Such a processor may be, but not limited to, a general purpose processor, a special purpose processor, an application specific processor, or a field programmable logic circuit. It will also be understood that each block of the block diagrams and/or flowcharts, and combinations of blocks of the block diagrams and/or flowcharts, can also be implemented by special purpose hardware for performing specified functions or actions, or can be implemented by a combination of special purpose hardware and computer instructions.
The above are only specific implementations of the present application, those skilled in the art can clearly understand that, for the convenience and brevity of the description, the specific working processes of the above-described systems, modules and units can be referred to the corresponding processes in the foregoing method embodiments, which is not repeated here. It should be understood that, the protection scope of the present application is not limited to this, and any person skilled in the art can easily think of various equivalent modifications or replacements within the technical scope disclosed in the present application, and these modifications or replacements should all be covered within the scope of protection of the present application.
| Number | Date | Country | Kind |
|---|---|---|---|
| 202211026510.7 | Aug 2022 | CN | national |
