This application claims priority to Chinese patent application No. CN202010479903.8 filed with CNIPA on May 29, 2020, the disclosure of which is incorporated herein by reference in its entirety.
The present disclosure relates to a field of display technology and, particularly, to an array substrate, a driving method of the array substrate, a display panel and a display device.
Active Matrix Organic Light Emitting Diode (AMOLED) display panels have gradually entered the market of display technologies. Compared with conventional Thin Film Transistor Liquid Crystal Display (TFT LCD) panels, the AMOLED Display panels have advantages of low energy consumption, self-luminescence, wide view angle, high response speed, easy applicability to a flexible display technology, etc. The AMOLED display panel may generally be driven by a current, that is, the drive current is used to control a light emitting module to emit light.
In order to control the drive current flowing through the light emitting module, a pixel circuit is usually required. At present, when the pixel circuit drives the light emitting module to emit light, a display panel in an idle mode has a significant flicker phenomenon and poor image display effect.
The present disclosure provides an array substrate, a driving method of the array substrate, a display panel and a display device.
In a first aspect, the embodiments of the present disclosure provide an array substrate. The array substrate include a plurality of pixel circuits arranged in an array, where the pixel circuit includes a drive module, a first initialization module, a second initialization module, a first light emitting control module, a data writing module and a light emitting module.
In a second aspect, the embodiments of the present disclosure further provide a display panel. The display panel includes any one array substrate provided in the first aspect.
In a third aspect, the embodiments of the present invention further provide a display device. The display device includes any one display panel provided in the second aspect.
In a fourth aspect, the embodiments of the present disclosure further provide a driving method of an array substrate, where the driving method is used to drive any one array substrate provided in the first aspect, and the driving method at least includes:
Hereinafter the present disclosure will be further described in detail with reference to the drawings and embodiments It is to be understood that the specific embodiments set forth below are intended to illustrate and not to limit the present disclosure. Additionally, it is to be noted that, for ease of description, only part, not all, of the structures related to the present disclosure are illustrated in the drawings.
Exemplarily, when a display panel (of a wearable product, for example) including the array substrate displays an image in the idle mode, low frequency display is generally used (such as, the 15 HZ drive time sequence is used for display). In the low frequency display, the pixel circuit maintains the potential through a storage capacitor. A control chip connected to the pixel circuit does not output after output one frame of data. At this time, clock signals CKH1 and CKH2 input to the scan drive circuit are pulled high, and correspondingly, scan signals Scan1, Scan2, and Scan3 output by the scan drive circuit are pulled high, as shown in
With reference to
With reference to
Exemplarily, In conjunction with
Specifically, when an Organic Light Emitting Diode (OLED) emits light, the light emitting signal Emit1 needs to be turned on, as the brightness curve shown in
In view of the above, embodiments of the present disclosure provide an array substrate, a driving method of the array substrate, a display panel, and a display device. For at least one of the above-mentioned reasons, a drive time sequence is set to reduce a coupling potential of the intermediate node N5 and/or N6, or to increase a reset frequency of the anode of the OLED, so that a brightness variation of the OLED is not distinguishable to the human eyes, thereby alleviating the flicker phenomenon.
The above is the core idea of the present disclosure, embodiments of the present disclosure will be described clearly and completely in conjunction with
Exemplarily,
The drive current of the drive module 110 flows through the light emitting module 150 to drive the light emitting module 150 to emit light. One of factors determining a magnitude of the drive current generated by the drive module 110 is the potential of the control terminal of the drive module 110, and the potential of the control terminal is affected by leakage currents of the first initialization module 121 and the second initialization module 122, and further, magnitudes of the leakage currents depend on a potential difference between the first intermediate node N01 and the control terminal of the drive module 110.
Based on this, it is set that within at least one light emitting period of one frame duration, the end time of the active level pulse of the first additional scan signal SR1 is later than the end time of the active level pulse of the first scan signal S1, so that: when the active level of the first scan signal S1 ends, only the second initialization module 122 is turned off, and the first initialization module 121 is still in an on state, and at this time, the potential of the first intermediate node N01 is still kept to a potential of the initialization signal terminal VREF; then, the active level of the first additional scan signal SR1 ends, the first initialization module 121 is turned off, and at this time, the first intermediate node N01 is only coupled one time by the potential of the first additional scan signal SR1 and is not affected by potential variation of the first scan signal S1, so that potential variation of the first intermediate node N01 is smaller, a potential difference between the first intermediate node N01 and the control terminal of the drive module 110 is smaller, the leakage currents of the first initialization module 121 and the second initialization module 122 is smaller, influence on the potential of the control terminal of the drive module 110 is smaller, and further influence on the drive current is smaller, that is, the fluctuation of the drive current is smaller, which is beneficial to alleviating the flicker phenomenon of the light emitting module 150, and is beneficial to improving the image display effect of the display panel and the display device.
The pixel circuit provided by the embodiments of the present disclosure is compared with the pixel circuit in the related art as follows: in the related art, a potential of an intermediate node of a double-gate transistor has a great influence on a leakage current of the control terminal (hereinafter may be simply referred to as “first node”) of the drive module; specifically, the higher the potential of the intermediate node of the double-gate transistor is, the larger the leakage current of the double-gate transistor relative to the first node is, and the more obvious the flicker phenomenon is. Referring to
It should be noted that In
It should be noted that
In an embodiment,
When the first additional scan signal SR1 and the first scan signal S1 are at an active level, the initialization signal of the initialization signal terminal VREF is transmitted to the control terminal of the drive module 110 through the first initialization module 121 and the second initialization module 122, and the control terminal is initialized, so as to ensure that the drive module 110 can normally operate subsequently. When the first additional scan signal SR1 is at an active level and the first scan signal S1 is at a disable level, the first initialization module 121 is turned on and the second initialization module 122 is turned off. By setting that the enable frequency of the first scan additional signal SR1 is greater than the enable frequency of the first scan signal S1, the first initialization module 121 can be turned on while the second initialization module 122 is turned off; at this time, the initialization signal of the initialization signal terminal VREF is transmitted to the first intermediate node N01, equivalently the initialization signal is used to reset the first intermediate node N01, so that the potential of the first intermediate node N01 can be maintained in a relatively stable state, so that a potential difference between the control terminal of the drive module 110 and the first intermediate node N01 is relatively stable, namely a fluctuation of the potential difference is small, so that the potential of the first intermediate node N01 has a small influence on the potential of the control terminal of the drive module 110, and the drive current generated by the drive module 110 has a small fluctuation, and the brightness of the light emitting module 150 has a small variation range, which is beneficial to alleviating the flicker phenomenon.
It should be noted that
In other embodiments, the enable frequency of the first additional scan signal SR1 may also be set to any other frequency greater than the enable frequency of the first scan signal S1. The enable frequency of the first additional scan signal may be set according to the requirements of the pixel circuit, which is not limited in the embodiments of the present disclosure.
In an embodiment,
With reference to
Within the leap delay duration Δt0 of the first scan signal S 1, the second initialization module 122 gradually turns off from the completely on state, and finally switches to the completely off state. By setting that the duration Δt1 from the end time of the active level pulse of the first scan signal S1 to the end time of the active level pulse of the first additional scan signal SR1 is greater than or equal to the leap delay duration of the first scan signal S1, when or after the module 122 is completely turned off, the first initialization module 121 starts to be turned off. By this way, it can be ensured that the first intermediate node N01 only couples variation amount of the leap potential of the first additional scan signal SR1 and is not affected by the potential leap of the first scan signal S1, so that the potential coupling amount of the first intermediate node N01 is smaller, which has less influence on the potential of the control terminal of the drive module 150, thereby alleviating the flicker phenomenon.
Exemplarily, a value range of Δt0 may be 0.5 μs≤Δt0≤3 μs. When Δt0=0.5 μs, Δt1 satisfies Δt1≥0.5 μs. In other embodiments, when the value of Δt0 varies, a time range of Δt1 varies accordingly.
It should be noted that
In an embodiment,
The first additional scan signal SR1 and the first scan signal S1 each are switching control signals. In the related art, the voltage difference between the active level and the inactive level of the two signals may be the same, thereby making the drive time sequence relatively simple while implementing the switching control.
In this embodiment, the smaller the voltage difference ΔV1 between the active level of the first additional scan signal SR1 and the inactive level of the first additional scan signal SR1 is, the smaller the coupling effect on the first intermediate node N01. Therefore, by setting that ΔV1<ΔV2, the coupling of the potential variation of the first additional scan signal SR1 to the first intermediate node N01 can be reduced, thereby alleviating the flicker.
In an embodiment,
Such a setting is beneficial to implementing a trace design in the array substrate 10, reduce the difficulty of the trace design and manufacturing, and thereby reducing the cost, which will be described in detail below in conjunction with
In an embodiment,
With this setting, on the basis of implementing functions of the above-mentioned modules, the circuit structure of these modules can be simpler, which is beneficial to saving circuit layout space and reducing manufacturing difficulty and manufacturing cost.
The first transistor T1 may also be referred as a drive transistor, and the second transistor T2, the third transistor T3, the fourth transistor T4, and the fifth transistor T5 each are switch transistors. A gate, a drain and a source of each transistor (including the switch transistor and the light emitting transistor) are respectively used as a control terminal, an input terminal and an output terminal of each module; the transistors coordinately work under the drive time sequence to drive the OLED to emit light. The specific working process will be described below in detail.
It should be noted that, in
It should be noted that
In an embodiment,
The smaller the width-to-length ratio of the channel region of the transistor is, the smaller the leakage current is. The second transistor T2 is connected between the first intermediate node N01 and the control terminal of the drive module 110. The width-to-length ratio of the channel region of the second transistor T2 is set to be relatively small, which is beneficial to reducing the leakage current between the first intermediate node N01 and the control terminal of the drive module 110, thereby reducing the influence of the first intermediate node N01 on the drive current of the drive module and alleviating the flicker phenomenon.
The width-to-length ratio of the channel region of the transistor is a ratio of a width of the channel to a length of the channel. Based on this, in order to implement that the width-to-length ratio of the channel region of the second transistor T2 is smaller than the width-to-length ratio of the channel region of the first transistor T1, it may be set that widths of channels of the two transistors are the same, and a length of a channel of the second transistor T2 is greater than a length of a channel of the first transistor T1; or it may be set that the lengths of the channels of the two transistors are the same, and the width of the channel of the second transistor T2 is smaller than the width of the channel of the first transistor T1; or it may be set that the length of the channel of the second transistor T2 is greater than the length of the channel of the first transistor T1, and meanwhile, the width of the channel of the second transistor T2 is smaller than the width of the channel of the first transistor T1, which is not limited in the embodiments of the present disclosure.
In an embodiment, with continued reference to
Two sides of the first intermediate node N01 are electrically connected to the first transistor T1 and the second transistor T2 respectively. The parasitic capacitance of the first intermediate node N01 includes not only the parasitic capacitances of the first transistor T1 and the second transistor T2, but also parasitic capacitance caused by the mutual influence between the first transistor T1 and the second transistor T2. Based on this, when the distance between the first transistor T1 and the second transistor T2 is relatively large, the mutual influence between the first transistor T1 and the second transistor T2 can be reduced, which is beneficial to reducing the parasitic capacitance of the first intermediate node N01, thereby reducing the variation of the coupling potential of the first intermediate node N01, reducing the leakage current between the first intermediate node N01 and the control terminal of the drive module 110, and alleviating the flicker phenomenon.
In other embodiments, it may be set that D1=6 μm, or 10 μm≥D1≥5.5 μm, or D1 may be set to be other numerical ranges known to those skilled in the art, which is not limited in the embodiments of the present disclosure.
It can be understood that in a practical product structure, the distance between the gate of the first transistor T1 and the gate of the second transistor T2 may define an extending length of a trace between the channel region of the first transistor T1 and the channel region of the second transistor T2 in an active layer corresponding to the first intermediate node N01.
It should be noted that, in
In an embodiment,
The third initialization module 123 is used for resetting the first electrode of the light emitting module 150. Exemplarily, when the light emitting module 150 is an OLED, the third initialization module 123 is used for resetting an anode of the OLED, and the enable frequency of the third scan signal S3 is also a reset frequency of the anode of the OLED.
In conjunction with
In addition, within a first light emitting period of one frame duration, the enable level period of the third scan signal S3 may coincide with the enable level period of the second scan signal S2. In this way, the data writing stage of the light emitting module coincides with the initialization stage of the light emitting module with the light emitting period. A duration occupied by the non-light emitting stage in the light emitting period is shorten while simplifying the sequence signal control manner, which is beneficial to extending the duration of the light emitting stage, avoid the flicker, and ensure a better display effect.
In an embodiment, with continued reference to
With this setting, the light emitting module 150 may be completely turned off before the light emitting stage of each light emitting period, which is beneficial to implementing that the brightness curve of turning of each light emitting control signal EMIT is basically the same, so that the human eye cannot recognize the flicker, thereby solving the flicker phenomenon.
Specifically, taking that the light emitting module 150 is an OLED as an example, in conjunction with the OLED reset process and OLED light emitting process, the alleviation of the flicker phenomenon is analyzed as follows: when the third scan signal S3 is in the active level period, the initialization signal terminal VREF may transmit an initialization signal Vref to the anode of the OLED, the initialization signal may be a low level signal.
Based on this, the OLED is reset using the initialization signal Vref Based on this, the light emitting process of the OLED is that the low-potential initialization signal Vref causes the anode of the OLED to quickly become a negative potential, the OLED is turned off, and at this time, the OLED does not emit light at all. When the light emitting control signal EMIT is turned on, firstly the capacitor of the OLED needs to be charged, and the anode potential of the OLED gradually rises, the anode potential of the OLED can only reach the normal light emitting potential after a period of time; at this time, the light emitting brightness of the OLED reaches its normal light emitting brightness. In general, using the initialization signal Vref to reset the anode potential of the OLED can cause that the OLED is completely turned off, the OLED light emitting time is delayed, and the OLED stays in a dark state for longer time.
In a hold frame in the idle mode, that is, in a process of only using the light emitting control signal EMIT to turn off the OLED and turn on the OLED, that the light emitting control signal EMIT turns off the OLED is essentially only to cut off a path of the current between the first power signal PVDD and the second power signal terminal PVEE, at this time, the existence of other leakage currents will cause the OLED to still have a certain brightness, that is, the OLED is not turned off completely. When the light emitting control signal EMIT enables again, because there is no initializing signal Vref to reset the anode of the OLED, the anode potential of the OLED still maintains the potential when the OLED emits light previously. Therefore, when the light emitting control signal EMIT enables, the OLED will rapidly start emitting light, that is, the time that the OLED is in the dark state is relatively short, and the brightness when the OLED is in the dark state is not black enough.
In conjunction with the above, it can be seen from a frame-maintaining brightness curve (that is, the brightness variation curve) in the related art that: among the brightness curves L01, L02, and L03, there is a very low-brightness valley in every four downward valleys. The low-brightness valley corresponds to the initialization signal Vref to reset the OLED, and the other three high-brightness valleys may correspond to the light emitting control signal EMIT to turn off the OLED. Since the low valley brightness is a low frequency (for example, 15 Hz frequency) brightness reduction, the human eye can recognize this phenomenon. In this embodiment, the OLED is reset by the initialization signal Vref while the light emitting control signal EMIT is set to be disabled, the pull-down low valley will appear at a high frequency (for example, a frequency of 60 Hz), and the human eye cannot recognize the brightness variation at this frequency, thereby implementing the alleviation of the flicker phenomenon.
In addition, the time sequence setting manner may be made simpler; at the same time, a same time sequence control circuit may be used to provide the third scan signal S3 and the light emitting control signal EMIT meanwhile. The circuit structure is relative simple, which is beneficial to decreasing the difficulty of designing and manufacturing the array substrate and to reduce the cost.
In an embodiment,
By this setting, the time sequence setting manner may be made simpler while alleviating the flicker phenomenon; at the same time, a same time sequence control circuit may be used to provide the third scan signal S3 and the first additional scan signal SR1 at the same time. The circuit structure is relative simple, which is beneficial to decreasing the difficulty of designing and manufacturing the array substrate and to reduce the cost.
Based on
The reset frequency of the OLED anode is equal to or greater than the dimming frequency. Exemplarily, when the dimming frequency is 15 Hz, the reset frequency of the OLED may be 60 Hz, 120 Hz, 180 Hz, 240 Hz or higher. Meanwhile, the enable level period of the first additional scan signal SR1 is within the disable level period of the light emitting control signal EMIT, and the enable frequency of the first additional scan signal SR1 is equal to or smaller than the enable frequency of the light emitting control signal EMIT. When no brightness flicker exists, the reset frequency of the OLED anode may be relatively low, such as 30 Hz, and the first additional scan signal SR1 may use the same frequency to reduce energy consumption.
In addition, since the human eye's recognizability of brightness flicker below 30 Hz is significantly increased, the reset frequency of the OLED anode may be set to be higher than 30 Hz, otherwise the flicker alleviation effect is not significant. At the same time, under different data refresh frequencies, such as 1 Hz and 60 Hz, 60 Hz may be used to reset the anode of the OLED. In this case, the first additional scan signal SR1 may have a same width of active level under the two different data refresh frequencies.
In other embodiments, based on the above-mentioned frequency setting manner, the above-mentioned frequencies may also be set to other frequency values known to those skilled in the art and the above-mentioned frequencies may be set according to the requirements of the array substrate, which is not limited in the embodiments of the present disclosure.
In an embodiment,
The first additional scan signal SR1 of the pixel circuit 1002 (100) in the current row and the third scan signal S3 of the pixel circuit 1001 (100) in the previous row may be provided by a same scan line (hereinafter “first scan line 201”). In this way, by designing the film pattern in the array substrate, the above-mentioned connection relationship may be implemented by a relatively simple trace manner, thereby simplifying the trace connection manner.
In an embodiment,
The sixth transistor T6 is a switch transistor, which is used for turning on or turning off under the control of the third scan signal S3, so as to reset the anode of the OLED. At the same time, such a setting can make the circuit structure of the third initialization module 123 relatively simple, which is beneficial to ensuring lower manufacturing difficulty and product cost.
In an embodiment,
On the basis of the improved manner shown in
In another embodiment, it may also be set that within at least one light emitting period of one frame duration, the end time tr2 of the active level pulse of the second additional scan signal SR2 is later than the end time t3 of the active level pulse of the fourth scan signal S4. By this setting, the first threshold compensation module 161 and the second threshold compensation module 162, which are simultaneously electrically connected to the second intermediate node N02, can be not turned off at the same time. In this way, the potential variation of the second intermediate node N02 will be reduced to the amount of coupling caused by the potential variation of the control terminal of the first threshold compensation module 161. Thus, compared to the amount of coupling caused by the potential variation of the control terminal of a double-gate transistor which is coupled by the second intermediate node N02 in the related art, the amount of coupling of the second intermediate node N02 is reduced. Therefore, the leakage current between the second intermediate node N02 and the control terminal of the drive module 110 will be reduced, and the influence on the control terminal of the drive module 110 will be relatively small, and the fluctuation of the drive current will be relatively small, which is beneficial to alleviating the flicker phenomenon.
Similar to the above-mentioned related time sequence improvement of the first intermediate node N01, the duration of the end time of the active level pulse of the second additional scan signal SR2 being later than the end time of the active level pulse of the fourth scan signal S4 may be set to be equal to or greater than the leap delay duration of the fourth scan signal S4; the voltage difference between the active level and the inactive level of the second additional scan signal SR2 may also be set to be smaller than the voltage difference between the active level and the inactive level of the fourth scan signal, and the relevant principles can be refer to the above explanations for understanding, which will not be repeated here.
In an embodiment,
The seventh transistor T7 and the eighth transistor T8 each are switch transistors. The seventh transistor T7 and the eighth transistor T8 cooperate with the above-mentioned transistors to implement the light emitting module 150 to emit light. At the same time, such a setting can make the circuit structures of the first threshold compensation module 161 and the second threshold compensation module 162 relatively simple, which is beneficial to ensuring lower manufacturing difficulty and product cost.
In an embodiment, with continued reference to
Similar to the above, the smaller the width-to-length ratio of the channel region of the transistor is, the smaller the leakage current is. Based on this, by setting the width-to-length ratio of the channel region of the transistor (that is, the seventh transistor T7) connected between the control terminal of the drive module 110 and the second intermediate node N02 to be relatively small, the leakage current between the second intermediate node N02 and the control terminal of the drive module 110 can be reduced, thereby reducing the influence of the potential of the second intermediate node N02 on the potential of the control terminal of the drive module 110, which is beneficial to reducing the fluctuation of the drive current and alleviate the flicker phenomenon.
Similar to implementing the relative relationship of the width-to-length ratio mentioned above, in order to implement that the width-to-length ratio of the channel region of the seventh transistor T7 is smaller than the width-to-length ratio of channel region of the eighth transistor T8, it may be set that the widths of the channels of the two transistors are the same, the length of the channel of the seventh transistor T7 is greater than the length of the channel of the eighth transistor T8; or it may be set that the lengths of the channels of the two transistors are the same, and the width of the channel of the seventh transistor T7 is smaller than the width of the channel of the eighth transistor T8; or it may be set that the length of the channel of the seventh transistor T7 is greater than the length of the channel of the eighth transistor T8, while the width of the channel of the seventh transistor T7 is smaller than the width of the channel of the eighth transistor T8.
In other embodiments, other manners known to those skilled in the art may also be used to implement that the leakage current of the second initialization module 122 is smaller than the leakage current of the first initialization module 121, and/or implement that the leakage current of the first threshold compensation module 161 is smaller than the leakage current of the second threshold compensation module 162, which is not limited in the embodiments of the present disclosure.
In an embodiment, with continued to reference to
The first scan line 201, the second scan line 202, the third scan line 203, and the light emitting control line 204 each are all used for providing gate control signals (also referred to as “switching control signals”) to control function modules electrically connected to them respectively in the on state or in the off state.
Exemplarily, the first scan line 201 may provide the first additional scan signal SR1 to the current row and the third scan signal S3 to the previous row, the second scan line 202 may provide the first scan signal S1, and the third scan line 203 may provide the second scan signal S2 and the light emitting control line 204 may provide the light emitting control signal EMIT.
The reset line 205, the data line 206, the first potential line 207, and the second potential line layer each are all used for providing a constant potential signal. Exemplarily, the reset line 205 may provide an initialization signal to the initialization signal terminal VREF, and the data line 206 may provide a data signal, and the data signal may pass through the data writing module 140, the second threshold compensation module 162, and the first threshold compensation module 161 and may be written to the control terminal of the drive module 110; the first potential line 207 may provide the first power signal, and the second potential line layer may be used as the second power signal terminal to provide the second power signal; exemplarily, the first power signal is higher than the second power signal, so that a potential difference between the two terminals of the light emitting module 150 exists, the drive current may flow through the light emitting module 150, and the light emitting module 150 may be driven to emit light.
In this way, at the trace layout level of the circuit layer, in order to implement that the input terminal of the first initialization module 121 in the current row is electrically connected to the reset node N03 in the previous row, and the first initialization module 121 in the current row and the third initialization module 123 in the previous row are provided the gate control signal by a same first scan line 201, the third initialization module 123 in the previous row and the first initialization module 121 in the current row may be centrally arranged in a same region and switch under the control of a same first scan line 201 extending along a horizontal direction. In this way, a cross-line design is not required. While implementing the connection relationship of the pixel circuit, a number of traces can be reduced, making the trace manner simple and easy to implement.
In an embodiment,
The trace manner is similar to the trace manner shown in
Such a setting is beneficial to simplifying the drive time sequence and reducing the number of traces, thereby reducing an area of the array substrate occupied by the traces, facilitating to reserve more area for the light emitting module 150, further increasing the pixel density and improving the image display effect.
In other embodiments, on the premise of satisfying the above-mentioned module functions and drive time sequence, the trace manner may be set to be other trace manners known to those skilled in the art, which is not limited in the embodiments of the present disclosure.
In an embodiment,
The second lighting control module 132 is electrically connected between the drive module 110 and the lighting emitting module 150. When the first lighting emitting control module 131 and the second light emitting control module 132 are turned on at the same time, the drive current generated by the drive module 110 flows through the light emitting module 150 and the light emitting module 150 is driven to emit light. Setting the second light emitting control module 132 is beneficial to ensuring that: after the third initialization module 123 resets the first electrode of the light emitting module 150, and the potential of the reset node N03 keeps stable, thereby avoiding the light emitting module 150 emitting undesired light.
In an embodiment,
The ninth transistor T9 is a switch transistor. Such a setting can make the circuit structure of the second light emitting control module 132 simple, which is beneficial to saving space, and at the same time ensuring that the array substrate has lower manufacturing difficulty and lower manufacturing cost.
In an embodiment,
The storage module 170 is used for maintaining a voltage of the control terminal of the drive module 110, exemplarily, for maintaining a gate voltage of the drive transistor; the drive module 110 generates a drive current to drive the light emitting module 150 to continuously emit light.
In an embodiment,
Such a setting can make the circuit structure of the storage module 170 simple, which is beneficial to saving space, and at the same time ensuring that the array substrate has lower manufacturing difficulty and lower manufacturing cost.
Taking
During the initialization stage, the first additional scan signal SR1 and the first scan signal S1 are low, the first transistor T1 and the second transistor T2 are turned on, and the initialization signal of the initialization signal terminal VREF is transmitted to the gate of the third transistor T3 through the first transistor T1 and the second transistor T2.
Then, the first scan signal S1 leaps to high, and the second transistor T2 is turned off; after the second transistor T2 is completely turned off, the first additional scan signal SR1 leaps to high, and the first transistor T1 is turned off
During the data writing stage, the second scan signal S2, the third scan signal S3, the fourth scan signal S4, and the second additional scan signal SR2 each are low, the fifth transistor T5, the sixth transistor T6, and the seventh transistor T7 and the eighth transistor T8 is turned on; at the same time, a low-level initialization signal is written into the gate of the third transistor T3 in the initialization stage, and the third transistor T3 is turned on. Based on this, the initialization signal of the initialization signal terminal VREF is transmitted to the reset node N03 through the sixth transistor T6; the data signal DATA is written to the gate of the third transistor T3 through the second transistor T2, the eighth transistor T8 and the seventh transistor T7, the gate potential of the third transistor T3 gradually increases until the third transistor T3 is turned off. At this time, the gate voltage of the third transistor T3 satisfies: is the voltage value of the data signal DATA, and is The threshold voltage of the third transistor T3.
Then, the second scan signal S2, the third scan signal S3, and the fourth scan signal S4 leap to high, the fifth transistor T5, the sixth transistor T6, and the eighth transistor T8 are turned off; after the eighth transistor T8 is completely turned off, the second additional scanning signal SR2 leaps to high, and the seventh transistor T7 is turned off
During the light emitting stage, the light emitting control signal EMIT is low, the fourth transistor T4 and the ninth transistor T9 are turned on, and the leakage current Id of the third transistor T3, that is, the drive current, drives the OLED to emit light through the ninth transistor T9. The drive current Id satisfies:
μ is the carrier mobility of the third transistor T3, W is the width of the channel of the third transistor T3 and L is the length of the channel of the third transistor T3, and Cox is the capacitance of the gate oxide layer per unit area of the third transistor T3. VPVDD is the voltage value of the first power signal. It can be seen that the drive current Id generated by the third transistor T3 is irrelevant to the threshold voltage Vth of the third transistor T3. The abnormal display caused by the drift of the threshold voltage of the third transistor T3 is solved. In addition, during the light emitting stage, the third transistor T3 works in the complete cut-off region, so that the characteristic drift degree of the third transistor T3 can be reduced, and the third transistor T3 works in the complete cut-off region in a partial stage of one frame, which is beneficial to reducing display Mura and sticking image, and improving the image display quality.
Meanwhile, compared with the related art in which the charges at the intermediate nodes of the double-gate transistors are accumulated through the coupling of the double gates, in the embodiment of the present disclosure, the module having the initialization function and the threshold compensation function for the gate of the third transistor is set as two independent single-gate transistors and the time sequences of the two independent single-gate transistors are independently controlled, so that the two independent single-gate transistors are not turned off at the same time, the coupling amount between the first intermediate node and the second intermediate node can be reduced, thereby reducing the leakage current between the first intermediate node and the gate of the third transistor T3 and the leakage current between the second intermediate node and the gate of the third transistor T3, and significantly reducing the flicker phenomenon.
Thereafter, in a light emitting period after the first light emitting period within one frame duration, the data is no longer refreshed, and the executable actions include at least one of: resetting the first intermediate node, resetting the OLED anode and resetting the second intermediate node, thereby further alleviating the flicker phenomenon.
On the basis, each gate control signal may be reused between adjacent rows, so that the initialization stages, the data writing stages and the light emitting stages of the pixel circuits in the adjacent rows can overlap in time, which is beneficial to shortening the interval between emitting light of the light emitting modules in the pixel circuits in the adjacent rows, thereby improving the display effect.
On the basis of the above embodiments, an embodiment of the present disclosure further provides a display panel including any one array substrate provided by the above embodiment of the present disclosure. Therefore, when the display panel is driven to display image, the flicker phenomenon is alleviated, and the image display effect is better.
By way of example,
In other embodiments, the display panel may further include other functional components or structural components known by those skilled in the art, which is neither described nor limited in the embodiments of the present disclosure.
On the basis of the above embodiments, an embodiment of the present disclosure further provides a display device, and the display device may include the display panel provided by the above embodiments. Therefore, when the display device is driven to display image, the flicker phenomenon is alleviated, and the image display effect is better.
Exemplarily,
In other embodiments, the display panel may further include a flexible printed circuit board, a system chip, and other functional components or structural components known by those skilled in the art, which is neither described nor limited in the embodiments of the present disclosure.
On the basis of the above embodiments, an embodiment of the present disclosure further provides a driving method for an array substrate. The driving method can be used for driving any one array substrate provided in the above embodiments to improving the display flicker phenomenon, that is, the driving method also has the beneficial effects of the pixel circuit provided in the above embodiments, and the same points can be understood with reference to the explanation of the pixel circuit above and are not described again in detail below.
Exemplarily,
In S510, a first additional scan signal is provided to the control terminal of the first initialization module.
Exemplarily, in conjunction with
In S520, a first scan signal is provided to the control terminal of the second initialization module.
Exemplarily, in conjunction with
Within at least one light emitting period of one frame duration, end time of an active level pulse of the first additional scan signal is later than end time of an active level pulse of the first scan signal, as shown in any one of
By this setting, the amount of coupling of the first intermediate node N01 can be reduced, thereby alleviating the flicker phenomenon.
In an embodiment, with continued reference to
In S610, a first additional scan signal is provided to the control terminal of the first initialization module.
In S620, a first scan signal is provided to the control terminal of the second initialization module.
In S630, a second scan signal is provided to the control terminal of the third initialization module.
Exemplarily, in conjunction with
The enable frequency of the second scan signal is greater than the enable frequency of the first scan signal, as shown in
By this setting, when data is refreshed at low frequency, the OLED anode may be reset at high frequency, so that the flicker phenomenon caused by low reset frequency can be alleviated.
In an embodiment, with continued reference to
The second additional scan signal is provided to the first threshold compensation module and the fourth scan signal is provided to the second threshold compensation module.
Exemplarily, in conjunction with
Within at least one light emitting period of one frame duration, end time of an active level pulse of the second additional scan signal is later than end time of an active level pulse of the fourth scan signal, as shown in
By this setting, the amount of coupling of the second intermediate node N02 can be reduced, thereby alleviating the flicker phenomenon.
According to the driving method of the pixel circuit provided by the embodiment of the present disclosure, based on the fact that the first initialization transistor and the second initialization transistor in the pixel circuit are respectively and independently controlled, the first threshold compensation module and the second threshold compensation module are respectively and independently controlled, and the control time sequence may be set to be off at different times, so that the amount of coupling of the first intermediate node and the second intermediate node corresponding to the level leap can be reduced, which is beneficial to reducing the leakage current between the first intermediate node and the control terminal of the drive module and the leakage current between the second intermediate node and the control terminal of the drive module, thereby alleviating the flicker phenomenon. Meanwhile, the first electrode reset frequency of the light emitting module is set to be higher, so that the time interval of brightness variation is smaller, the trend of brightness variation is more consistent, human eyes cannot distinguish brightness variation, and flicker can be alleviated.
It is to be noted that the above are only some embodiments of the present disclosure and the technical principles used therein. It will be understood by those skilled in the art that the present disclosure is not limited to the specific embodiments described herein. Those skilled in the art can make various apparent modifications, adaptations, combinations and substitutions without departing from the scope of the present disclosure. Therefore, while the present disclosure has been described in detail through the above-mentioned embodiments, the present disclosure is not limited to the above-mentioned embodiments and may include more other equivalent embodiments without departing from the concept of the present disclosure. The scope of the present disclosure is determined by the scope of the appended claims.
Number | Date | Country | Kind |
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202010479903.8 | May 2020 | CN | national |