Patent Grant
11610534
This disclosure relates to the field of display technology, in particular to a sub-pixel structure and a display.
Traditional micro light-emitting diodes (LED) are controlled by currents. Since the inorganic gallium nitride material, from which the Micro LED is made, will rapidly decay under long-term driving, the brightness of the Micro LED will decrease and the service life of the Micro LED will be decreased. At the same time, due to the threshold voltage drift of the thin film transistor and the different decay rates of different RGB organic materials, the Micro LED is prone to inconsistent brightness after a certain period of time. Different display images are driven by different currents, and the resulting decay rates are also different. Displaying a static image for a long period of time will cause uneven display or image retention (i.e., afterimage).
Brightness of the Micro LED is controlled based on the current, and the current is controlled based on the voltage. The micro LED has a poor uniformity due to mass transfer process. In addition, thin film transistors also have poor uniformity. At normal high grayscales, the brightness is high, and it is difficult for the human eye to distinguish the difference in brightness. However, at low grayscales, the display drive current is small, and the variability of thin film transistors will affect the display effect, resulting in uneven display distinguished by the human eye, and the pictures turn grainy, that is, display brightness is uneven at low grayscales.
Therefore, the existing technology needs to be improved and promoted.
In view of the above-mentioned shortcomings of the related art, the disclosure aims at providing a sub-pixel structure and a display. By using dual-electrode separation, it is possible to achieve display of time-sharing control and zone control, slow down the decay rate of material, prolong the service life, and reduce afterimage formed due to difference in material decay.
In order to achieve above objectives, the disclosure adopts the following technical solutions.
A sub-pixel structure is provided. The sub-pixel structure includes a driving module, a first selection module, a second selection module, a switch module, a first light-emitting element, and a second light-emitting element. The driving module has a first terminal coupled with a first supply terminal and a second terminal coupled to a first terminal of the first selection module. The first selection module has a second terminal coupled with an anode of the first light-emitting element and an anode of the second light-emitting element, and has a third terminal configured to receive a first control signal, where the first control signal is used to control conduction between the driving module and the anode of the first light-emitting element or conduction between the driving module and the anode of the second light-emitting element. The second selection module has a first terminal coupled with a cathode of the first light-emitting element and a cathode of the second light-emitting element, and has a second terminal configured to receive a second control signal, where the second control signal is used to control grounding of the cathode of the first light-emitting element or grounding of the cathode of the second light-emitting element. The switch module has a first terminal coupled with the anode of the first light-emitting element and the anode of the second light-emitting element, and has a second terminal coupled with the cathode of the first light-emitting element and the cathode of the second light-emitting element. The switch module has a third terminal configured to receive a third control signal and a fourth control signal, where the third control signal is used to control simultaneous conduction or non-simultaneous conduction of the anode of the first light-emitting element and the anode of the second light-emitting element, and the fourth control signal is used to control simultaneous conduction or non-simultaneous conduction of the cathode of the first light-emitting element and the cathode of the second light-emitting element.
In an implementation, the switch module includes a first switch unit and a second switch unit. The first switch unit has a first terminal coupled with the anode of the first light-emitting element, a second terminal coupled with the anode of the second light-emitting element, and a third terminal configured to receive the third control signal, where the third control signal is used to control simultaneous conduction or non-simultaneous conduction of the anode of the first light-emitting element and the anode of the second light-emitting element. The second switch unit has a first terminal coupled with the cathode of the first light-emitting element, a second terminal coupled with the cathode of the second light-emitting element, and a third terminal configured to receive the fourth control signal, where the fourth control signal is used to control simultaneous conduction or non-simultaneous conduction of the cathode of the first light-emitting element and the cathode of the second light-emitting element.
In an implementation, the first selection module includes a first switch transistor and a second switch transistor. The first switch transistor has a first terminal coupled with the driving module, a second terminal coupled with the anode of the first light-emitting element, and a third terminal configured to receive the first control signal. The second switch transistor has a first terminal coupled with the driving module, a second terminal coupled with the anode of the second light-emitting element, and a third terminal configured to receive the first control signal.
In an implementation, the second selection module includes a third switch transistor and a fourth switch transistor. The third switch transistor has a first terminal coupled with the cathode of the first light-emitting element, a second terminal configured to receive the second control signal, and a third terminal coupled with a second supply terminal. The fourth switch transistor has a first terminal coupled with the cathode of the second light-emitting element, a second terminal configured to receive the second control signal, and a third terminal coupled with the second supply terminal.
In an implementation, the first switch unit includes a fifth switch transistor, and the fifth switch transistor has a first terminal coupled with the anode of the first light-emitting element, a second terminal coupled with the anode of the second light-emitting element, and a third terminal configured to receive the third control signal.
In an implementation, the second switch unit includes a sixth switch transistor, and the sixth switch transistor includes a first terminal coupled with the cathode of the first light-emitting element, a second terminal coupled with the cathode of the second light-emitting element, and a third terminal configured to receive the fourth control signal.
In an implementation, the driving module includes a seventh switch transistor, and the seventh switch transistor has a first terminal coupled with the first supply terminal, a second terminal coupled with the first selection module, and a third terminal coupled with a control signal input terminal.
In an implementation, the sub-pixel structure further includes a data module and a maintenance module. The data module is coupled with a scan line, a data line, and the driving module. The maintenance module has one terminal coupled with the first supply terminal and the other terminal coupled with a first terminal of the data module and a third terminal of the driving module, and the maintenance module is configured to maintain a stable potential difference between the driving module and the first supply terminal. The data module has a second terminal coupled with the data line and a third terminal coupled with the scan line. The scan line is configured to turn on or turn off the data module. The data line is configured to provide data information when the data module is turned on.
In an implementation, the data module includes an eighth switch transistor, and the eighth switch transistor has a first terminal coupled with the data line, a second terminal coupled with the third terminal of the driving module and the other terminal of the maintenance module, and a third terminal coupled with the scan line.
A display is provided. The display includes a pixel array. The pixel array includes at least one pixel circuit, and the at least one pixel circuit includes the above three sub-pixel structures.
Compared with the related art, a sub-pixel array and a display are provided. The sub-pixel structure includes the driving module, the first selection module, the second selection module, the switch module, the first light-emitting element, and the second light-emitting element. The first selection module is configured to control conduction between the driving module and the anode of the first light-emitting element or conduction between the driving module and the anode of the second light-emitting element through the first control signal. The second selection module is configured to control grounding of the cathode of the first light-emitting element or grounding of the cathode of the second light-emitting element through the second control signal. The switch module is configured to control simultaneous conduction or non-simultaneous conduction of the anode of the first light-emitting element and the anode of the second light-emitting element through the third control signal and to control simultaneous conduction or non-simultaneous conduction of the cathode of the first light-emitting element and the cathode of the second light-emitting element through the fourth control signal. By using dual-electrode separation, it is possible to achieve display of time-sharing control and zone control, slow down the decay rate of material, prolong the service life, and reduce afterimage formed due to difference in material decay.
A sub-pixel structure and a display are provided. By using dual-electrode separation, it is possible to achieve display of time-sharing control and zone control, slow down the decay rate of material, prolong the service life, and reduce afterimage formed due to difference in material decay.
Objectives, technical solutions, and advantages of the disclosure will be described clearly and completely hereinafter with reference to the accompanying drawings in the implementations of the disclosure. It is noted that the implementations described herein are used to merely explain rather than limit the disclosure.
Referring to
The second selection module 300 has a first terminal coupled with a cathode of the first light-emitting element LED1 and a cathode of the second light-emitting element LED2. The second selection module 300 has a second terminal configured to receive a second control signal. The second control signal is used to control grounding of the cathode of the first light-emitting element LED1 or grounding of the cathode of the second light-emitting element LED2. The switch module 400 has a first terminal coupled with the anode of the first light-emitting element and the anode of the second light-emitting element. The switch module 400 has a second terminal coupled with the cathode of the first light-emitting element and the cathode of the second light-emitting element. The switch module 400 has a third terminal configured to receive a third control signal and a fourth control signal. The third control signal is used to control simultaneous conduction or non-simultaneous conduction of the anode of the first light-emitting element LED1 and the anode of the second light-emitting element LED2. The fourth control signal is used to control simultaneous conduction or non-simultaneous conduction of the cathode of the first light-emitting element LED1 and the cathode of the second light-emitting element LED2. According to the disclosure, the dual-electrode separation in the sub-pixel structure is realized by arranging two light-emitting elements. Two anodes, as well as two cathodes, of the two light-emitting elements are separated and independent. As such, switching of multiple light-emitting modes and light-emitting display of different regions are realized. The intermittent operation of each light-emitting element avoids loading the driving current for long periods, prolongs the service life, and reduces afterimage formed due to difference in material decay.
Referring to
Referring to
In an implementation, the second selection module 300 includes a third switch transistor T3 and a fourth switch transistor T4. The third switch transistor T3 has a first terminal coupled with the cathode of the first light-emitting element LED2, a second terminal configured to receive the second control signal, and a third terminal coupled with a second supply terminal VSS. The fourth switch transistor T4 has a first terminal coupled with the cathode of the second light-emitting element, a second terminal configured to receive the second control signal, and a third terminal coupled with the second supply terminal VSS. Similarly, in this implementation, the second control signal includes two signals which are respectively used to control the turn on or turn off of the third switch transistor T3 and the fourth switch transistor T4, and whose control timings are also complementary. When the third switch transistor T3 is turned on (or turned off), the fourth switch transistor T4 is turned off (or turned on). As such, the second control signal controls the on and off of the third switch transistor T3 and the fourth switch transistor T4 to enable grounding paths of the light-emitting elements to be changeable.
In an implementation, the first switch unit 410 includes a fifth switch transistor T5. The fifth switch transistor T5 has a first terminal coupled with the anode of the first light-emitting element LED1, a second terminal coupled with the anode of the second light-emitting element LED2, and a third terminal configured to receive the third control signal Ctl1. The third control signal Ctl1 controls whether the anode of the first light-emitting element LED1 and the anode of the second light-emitting element LED2 are simultaneously conducted by controlling the turn on or turn off of the fifth switch transistor T5. In an implementation, when the third control signal Ctl1 controls the fifth switch transistor T5 to be turned on, the anodes of the first light-emitting element LED1 and the second light-emitting element LED2 are simultaneously conducted. At this point, no matter which one of the first switch transistor T1 and the second switch transistor T2 is turned on, the driving current of the driving module 100 will flow to the anodes of the first light-emitting element LED1 and the second light-emitting element LED2 at the same time.
In an implementation, the second switch unit 420 includes a sixth switch transistor T6. The sixth switch transistor T6 includes a first terminal coupled with the cathode of the first light-emitting element LED1, a second terminal coupled with the cathode of the second light-emitting element LED2, and a third terminal configured to receive the fourth control signal Ctl2. The fourth control signal Ctl2 controls whether the cathode of the first light-emitting element LED1 and the cathode of the second light-emitting element LED2 are simultaneously conducted by controlling the turn on or turn off of the sixth switch transistor T6. In an implementation, when the fourth control signal Ctl2 controls the sixth switch transistor T6 to be turned on, the cathodes of the first light-emitting element LED1 and the second light-emitting element LED2 are simultaneously conducted. At this point, no matter which one of the third switch transistor T3 and the fourth switch transistor T4 is turned on, the cathodes of the first light-emitting element LED1 and the second light-emitting element LED2 are simultaneously conducted to the ground.
In an implementation, the driving module 100 includes a seventh switch transistor T7. The seventh switch transistor T7 has a first terminal VDD coupled with the first supply terminal, a second terminal coupled with the first selection module 200, and a third terminal coupled with a control signal input terminal. A control signal inputted from the control signal input terminal is used to control the turn-on or turn-off of the seventh switch transistor T7. When the seventh switch transistor T7 is turned on, the driving current is provided for the first light-emitting element LED1 and/or the second light-emitting element LED2, so as to drive the first light-emitting element LED1 and/or the second light-emitting element LED2 to light up.
In an implementation, the sub-pixel structure further includes a data module 500 and a maintenance module 600. The data module 500 is coupled with a scan line, a data line, and the driving module 100. The maintenance module 600 has one terminal coupled with the first supply terminal VDD and the other terminal coupled with a first terminal of the data module 500 and a third terminal of the driving module 100. The data module 500 has a second terminal coupled with the data line and a third terminal coupled with the scan line. The scan line is configured to turn on or turn off the data module 500. The data line is configured to provide data information when the data module 500 is turned on. The maintenance module 600 is configured to maintain a stable potential difference between the driving module 100 and the first supply terminal VDD, so as to ensure that the driving module 100 can provide effective driving current, as well as data information needed for display, for the first light-emitting element LED1 and the second light-emitting element LED2.
In an implementation, the data module 500 includes an eighth switch transistor T8. The eighth switch transistor T8 has a first terminal coupled with the data line, a second terminal coupled with the third terminal of the seventh switch transistor T7 and the other terminal of the maintenance module 600, and a third terminal coupled with the scan line. The scan line controls the turn on or turn off of the eighth switch transistor T8. When the eighth switch transistor T8 is turned on, the data information of the data line is output to the seventh switch transistor T7 through the eighth switch transistor T8, and the seventh switch transistor T7 is turned on, so as to realize the drive control of the first light-emitting element LED1 or/and the second light-emitting element LED2.
In an implementation, the maintenance module 600 includes a capacitor C1. The capacitor C1 has one terminal coupled with the first supply terminal VDD, and the other terminal coupled with the second terminal of the eighth switch transistor T8 and the third terminal of the seventh switch transistor T7. The capacitor C1 can maintain a stable potential difference between the first supply terminal VDD and the third terminal of the seventh switch transistor T7, thereby ensuring normal drive control of the seventh switch transistor T7.
In an implementation, when the scan line controls the eighth switch transistor T8 to be turned on, the data information is output to the seventh switch transistor T7 through the eighth switch transistor T8, and the seventh switch transistor T7 is controlled to be turned on to provide the driving current for the light emitting elements. Since the two-electrode separation structure is provided in the present disclosure, the driving current will not directly flow through the light-emitting element. Instead, the driving current will be outputted to the light-emitting element after passing through the first switch transistor T1 or the second switch transistor T2. In combination with the first control signal, the second control signal, the third control signal, and each switch transistor, the pixel structure of the disclosure can provide three display states, that is, a low grayscale state, a medium brightness state, and a high brightness state.
In the grayscale state, the first control signal CK controls the first switch transistor T1 to be turned on, the first control signal CB controls the second switch transistor T2 to be turned off, the third control signal Ctl1 controls the fifth switch transistor T5 to be turned off, the fourth control signal Ctl2 controls the sixth switch transistor T6 to be turned on, and the second control signal controls the third switch transistor T3 to be turned off and controls the fourth switch transistor T4 to be turned on. At this time, the anode of the first light-emitting element LED1 receives the driving current, the cathode of the first light-emitting element LED1 is not conducted to the ground, and the cathode of the second light-emitting element LED2 is conducted to the ground. At such, the driving current flows into the anode of the first light-emitting element LED1 through the first switch transistor T1, then flows from the cathode of the first switch transistor T1 to the sixth switch transistor T6, and flows to the ground from the cathode of the second light-emitting element LED2, so that the first light-emitting element LED1 is lighted up. Alternatively, the first control signal CK controls the first switch transistor T1 to be turned off, the first control signal CB controls the second switch transistor T2 to be turned on, the third control signal Ctl1 controls the fifth switch transistor T5 to be turned off, the fourth control signal Ctl2 controls the sixth switch transistor T6 to be turned on, the second control signal controls the third switch transistor T3 to be turned on and controls the fourth switch transistor T4 to be turned off. At this time, the anode of the second light-emitting element LED2 receives the driving current, and the cathode of the first light-emitting element LED1 is conducted to the ground. As such, the driving current flows through the second light-emitting element LED2 via the second switch transistor T2, so that the second light-emitting element LED2 is lighted up. In other words, when the driving current flows through the anode of only one of the two light-emitting elements and the cathode of the other light-emitting element to the ground, the sub-pixel structure is in the low grayscale state, the brightness is the lowest, and there is only one light-emitting element displaying, which results in a displaying of small area. In this implementation, the first light-emitting element LED1 is a micro LED. The first light-emitting element LED1 and the second light-emitting element LED2 are LEDs of the same color.
In the medium brightness state, the first control signal CK controls the first switch transistor T1 to be turned on, the first control signal CB controls the second switch transistor T1 to be turned off, the third control signal Ctl1 controls the fifth switch transistor T5 to be turned off, and the fourth control signal Ctl2 controls the sixth switch transistor T6 to be turned off, the second control signal controls the third switch transistor T3 to be turned on and controls the fourth switch transistor T4 to be turned off. At this time, the cathode of the first light-emitting element LED1 is grounded and the first light-emitting element LED1 is turned on. The driving current flows through the first light-emitting element LED1 via the first switch transistor T1, so that the first light-emitting element LED1 is lighted up. Alternatively, the first control signal CK controls the first switch transistor T1 to be turned off, the first control signal CB controls the second switch transistor T2 to be turned on, the third control signal Ctl1 controls the fifth switch transistor T5 to be turned off, and the fourth control signal Ctl2 controls the sixth switch transistor T6 to be turned off, and the second control signal controls the third switch transistor T3 to be turned off and controls the fourth switch transistor T4 to be turned on. At this time, the cathode of the second light-emitting element LED2 is grounded and the second light-emitting element LED2 is turned on. The driving current flows through the second light-emitting element LED2 via the second switch transistor T2, so that the second light-emitting element LED2 is lighted up. In other words, when the driving current flows through the anode and cathode of only one of the two light-emitting elements to the ground, the sub-pixel structure is in the medium brightness state, and there is only one light-emitting element displaying, and the medium grayscale display is obtained.
In the high brightness state, the first control signal CK controls the first switch transistor T1 to be turned on, the first control signal CB controls the second switch transistor T2 to be turned off, the third control signal Ctl1 controls the fifth switch transistor T5 to be turned on, and the fourth control signal Ctl2 controls the sixth switch transistor T6 to be turned on, and the second control signal controls the third switch transistor T3 to be turned on and controls the fourth switch transistor T4 to be turned off. At this time, the driving current flows into the anode of the first light-emitting element LED1 and the anode of the second light-emitting element LED2 at the same time, and the cathode of the first light-emitting element LED1 and the cathode of the second light-emitting element LED2 are conducted to the ground at the same time. The driving current flows through the first light-emitting element LED1 and the second light-emitting element LED2 via the first switch transistor T1, the cathode of the first light-emitting element LED1 and the cathode of the second light-emitting element LED2 are both conducted to the ground through the third switch transistor T3. Alternatively, the first control signal CK controls the first switch transistor T1 to be turned off, the first control signal CB controls the second switch transistor T2 to be turned on, the third control signal Ctl1 controls the fifth switch transistor T5 to be turned on, the fourth control signal Ctl2 controls the sixth switch transistor T6 to be turned on, and the second control signal controls the third switch transistor T3 to be turned off and controls the fourth switch transistor T4 to be turned on. At this time, the driving current flows into the anode of the first light-emitting element LED1 and the anode of the second light-emitting element LED2 at the same time, and the cathode of the first light-emitting element LED1 and the cathode of the second light-emitting element LED2 are conducted to the ground at the same time. The driving current flows through the first light-emitting element LED1 and the second light-emitting element LED2 via the second switch transistor T2, the cathode of the first light-emitting element LED1 and the cathode of the second light-emitting element LED2 are both conducted to the ground through the fourth switch transistor T4. In other words, in the high brightness state, the first light-emitting element LED1 and the second light-emitting element LED2 are all turned on to light up.
Lighting up two light-emitting elements in the high brightness state allows has a larger light-emitting area than lighting up only one light-emitting element. A larger light-emitting area corresponds to a greater pixels per inch (PPI) of a display panel in the display. A greater PPI means that the display can display images with higher density, the graininess will be reduced, and the brightness of the display panel will be increased, which results in a high grayscale display. When only one light-emitting element emits light for displaying, the brightness of the display panel will be low, which results in a low grayscale display. As such, different brightness displays can be obtained by selecting different modes, but the driving current will not be small, and precise control can be achieved, thereby avoiding display unevenness due to a small current in the low grayscale display.
Referring to
In an implementation, each of the first switch transistor T1, the second switch transistor T2, the third switch transistor T3, the fourth switch transistor T4, the fifth switch transistor T5, the sixth switch transistor T6, the seventh switch transistor T7, and the eighth switch transistor T8 is a thin film transistor.
It is noted that the above-mentioned first terminal can be a source or a drain, the second terminal can be a drain or a source, and the third terminal is a gate.
A display is further provided. The display includes a pixel array. The pixel array includes at least one pixel circuit. The at least one pixel circuit includes the above-mentioned three sub-pixel structures. The sub-pixel structure has been described in detail above, and will not be repeated herein.
The pixel array and the display are provided. The sub-pixel structure includes the driving module, the first selection module, the second selection module, the switch module, the first light-emitting element, and the second light-emitting element. The first selection module is configured to control conduction between the driving module and the anode of the first light-emitting element or conduction between the driving module and the anode of the second light-emitting element through the first control signal. The second selection module is configured to control grounding of the cathode of the first light-emitting element or grounding of the cathode of the second light-emitting element through the second control signal. The switch module is configured to control simultaneous conduction or non-simultaneous conduction of the anode of the first light-emitting element and the anode of the second light-emitting element through the third control signal and to control simultaneous conduction or non-simultaneous conduction of the cathode of the first light-emitting element and the cathode of the second light-emitting element through the fourth control signal. By using dual-electrode separation, it is possible to achieve display of time-sharing control and zone control, slow down the decay rate of material, prolong the service life, and reduce afterimage formed due to difference in material decay.
It is noted that for those of ordinary skill in the art, equivalent replacements or variations can be made according to the technical solution of the present disclosure and its inventive concept, and these replacements or variations are also considered to fall into the protection scope of the appended claims of the present disclosure.
The present application is a continuation of International Application No. PCT/CN2020/091373, filed on May 20, 2020, the disclosure of which is hereby incorporated by reference in its entirety.
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| Number | Date | Country | |
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| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/CN2020/091373 | May 2020 | US |
| Child | 17360576 | US |
