Patent Grant
11756484
This application claims priority to Chinese patent application No. 202211008776.9 filed on Aug. 22, 2022, the disclosure of which is incorporated herein by reference in its entirety.
Embodiments of the present disclosure relate to the field of display technology and, in particular, to a light-emitting panel, a driving method of a light-emitting panel, and a display device.
With the continuous improvement of the display technology, display requirements for display panels are increasing. In existing display panel, a drive transistor used to drive a light-emitting element to emit light typically works at a saturation area so that the drive transistor can provide a stable current to ensure stable light emission of the light-emitting element. However, the drive transistor working at a saturation area causes an increase in power consumption of the display panel. Therefore, a decrease in power consumption of the display panel becomes an urgent problem to be solved.
The present disclosure provides a light-emitting panel, a driving method of a light-emitting panel, and a display device to reduce the overall power consumption of the light-emitting panel and the thickness of the light-emitting panel to facilitate narrowing the border of the light-emitting panel.
An embodiment of the present disclosure provides a light-emitting panel. The light-emitting panel includes a substrate, a plurality of light-emitting units, a plurality of first switch units, and a constant-current circuit.
The plurality of light-emitting units are disposed on one side of the substrate and are arranged in an array along a first direction and a second direction. The first direction and the second direction intersect each other and are parallel to the plane where the substrate is located.
A first terminal of a light-emitting unit of the plurality of light-emitting units is electrically connected to a first supply voltage terminal, and a second terminal of the light-emitting unit is electrically connected to a first terminal of a respective first switch unit of the plurality first switch units. The control terminal of the first switch unit is electrically connected to a scan signal line extending along the first direction. The second terminal of the first switch unit is electrically connected to a data signal line extending along the second direction.
The output terminal of the constant-current circuit is electrically connected to the data signal line.
An embodiment of the present disclosure further provides a driving method of a light-emitting panel. The method is applied to the light-emitting panel described in the above-mentioned embodiment. The driving method includes acquiring a to-be-displayed grayscale value of a light-emitting unit; determining the drive current required by the light-emitting unit according to the grayscale value; controlling a constant-current circuit to supply a current to a corresponding data signal line according to the magnitude of the drive current; controlling a first switch unit to turn on so that the light-emitting unit emits light.
An embodiment of the present disclosure further provides a display device including the light-emitting panel described in the above-mentioned embodiment.
According to embodiments of the present disclosure, by electrical connection between the constant-current circuit and data signal lines, constant currents are output to the data signal lines. When a scan signal provided by a scan signal line controls first switch units to turn on, the output currents are transmitted to the light-emitting units. At the same time, under the action of the first supply voltage terminal, all light-emitting units electrically connected to the scan signal line perform light-emitting display. Depending on different luminances of the light-emitting panel, the currents required by the light-emitting units are different. It is feasible to adjust the magnitudes of the constant currents output by the output terminals of the constant-current circuit to adjust the luminances of the light-emitting units to satisfy the requirements for different luminances of the light-emitting panel or to satisfy the requirements for adjusting the luminances by zone, thereby improving the display quality of the light-emitting panel. Moreover, there is no need to provide an additional light-emitting drive circuit (for example, 7T1C pixel drive circuit). In this manner, the overall power consumption of the light-emitting panel is saved, the circuit layout is simplified, and the cost is reduced, thereby facilitating thinning and narrowing the border of the light-emitting panel.
It is to be understood that the content described in this part is not intended to identify key or important features of embodiments of the present disclosure and is not intended to limit the scope of the present disclosure. Other features of the present disclosure are apparent from the description hereinafter.
To illustrate embodiments of the present disclosure more clearly, drawings used in description of the embodiments are briefly described below. Apparently, the drawings described below merely illustrate part of embodiments of the present disclosure, and those skilled in the art may obtain other drawings based on the drawings on the premise that no creative work is done.
For a better understanding of the present disclosure by those skilled in the art, embodiments of the present disclosure are described clearly and completely in conjunction with the drawings in embodiments of the present disclosure. Apparently, the embodiments described below are part, not all, of embodiments of the present disclosure. Based on the embodiments described herein, all other embodiments obtained by those skilled in the art on the premise that no creative work is done are within the scope of the present disclosure.
It is to be noted that the terms “first”, “second” and the like in the description, claims and drawings of the present disclosure are used to distinguish between similar objects and are not necessarily used to describe a particular order or sequence. It should be understood that the data used in this manner are interchangeable where appropriate so that embodiments of the present disclosure described herein may also be implemented in a sequence not illustrated or described herein. In addition, the terms “include”, “have” or any other variations thereof are intended to encompass a non-exclusive inclusion. For example, a process, method, system, product or equipment that includes a series of steps or units not only includes the expressly listed steps or units but may also include other steps or units that are not expressly listed or are inherent to such process, method, product or equipment.
Here, the ellipses in
The light-emitting unit 11 may be formed of a light-emitting element (for example, a light-emitting diode) or multiple light-emitting elements, which is not limited in the embodiment of the present disclosure. The light-emitting element includes, but is not limited to, a submillimeter light-emitting diode or a micro light-emitting diode. The light-emitting panel according to the embodiment of the present disclosure may be a display panel directly performing image display, or may be a backlight panel providing light for other display panel, which is not limited in the embodiment of the present disclosure. For ease of description, the embodiment of the present disclosure is described in terms of an example in which a light-emitting panel is a display panel directly performing image display.
The first switch unit 12 may be a switch transistor, and specifically may be a P-type or an N-type, which is not limited in the embodiment of the present disclosure. If the first switch unit 12 is a P-type switch transistor, when a scan signal provided by a scan signal line is at a low level, the first switch unit 12 is controlled to be turned on; if the scan signal is at a high level, the first switch unit 12 is controlled to be turned off. Alternatively, if the first switch unit 12 is an N-type switch transistor, when the scan signal provided by the scan signal line is at the high level, the first switch unit 12 is controlled to be turned on; if the scan signal is at the low level, the first switch unit 12 is controlled to be turned off.
In an exemplary embodiment, when the scan signal provided by a scan signal line 13 in a certain row is a valid scan signal, all the first switch units 12 electrically connected to the scan signal line 13 are controlled to turned on, and at this time, the current output by the constant-current circuit 15 is transmitted to the first switch units 12 through respective data lines 14 and then to the light-emitting units 11. At the same time, under the action of the first supply voltage terminal V1, all the light-emitting units 11 electrically connected to the scan signal line 13 in the row perform light-emitting display. In this manner, the constant-current circuit 15 directly supplies stable currents to the light-emitting units 11, and no additional light-emitting drive circuit (for example, 7T1C pixel drive circuit) is required. Thus, the power consumption of the light-emitting panel can be reduced, and the heat dissipation difficulty caused by the large power consumption of the light-emitting panel can be avoided, thereby improving the quality of the light-emitting panel. Moreover, narrowing the border of the light-emitting panel is facilitated, the screen-to-body ratio is improved, and the cost of the light-emitting panel can be reduced.
It is to be understood that the luminance of the light-emitting unit 11 may be different depending on the value of the output current of the constant-current circuit 15. The value of the specific output current of the constant-current circuit 15 is not limited by the embodiment. The output current of the constant-current circuit 15 may be a fixed current or an arbitrarily adjustable current. Those skilled in the art may make selections according to actual requirements. In an exemplary embodiment, the multiple light-emitting units 11 arranged in an array in the light-emitting panel may be divided in multiple zones, and the data lines corresponding to each zone may receive a different current value of the constant-current circuit 15 so that the luminance of the light-emitting panel can be adjusted by zones.
It is to be noted that the multiple light-emitting units 11 arranged in the same column along the second direction Y may be electrically connected to the same data signal line 14, or may be electrically connected to different data signal lines 14, which is not limited in the embodiment of the present disclosure. It is to be understood that when multiple light-emitting units 11 in the same column are electrically connected to different data signal lines 14, to satisfy the luminance requirements of the light-emitting units 11 in different places of the light-emitting panel, the constant-current circuit 15 may output corresponding different currents to improve the display quality.
In the embodiment of the present disclosure, by electrical connection between the constant-current circuit and the data signal lines, the constant current is output to the data signal line. When the scan signal provided by the scan signal line controls the first switch unit to turn on, the output current is transmitted to the light-emitting unit. At the same time, under the action of the first supply voltage terminal, all light-emitting units electrically connected to the scan signal line in the same row perform light-emitting display. According to different luminances of the light-emitting panel, the current required by the light-emitting unit is different. The luminance can be adjusted by adjusting the value of the constant current output by the output terminal of the constant-current circuit to satisfy the requirements for different luminances of the light-emitting panel or to satisfy the requirements for adjusting luminance by zone, thereby improving the display quality of the light-emitting panel. Moreover, there is no need to provide an additional light-emitting drive circuit (for example, 7T1C pixel drive circuit). In this manner, the overall power consumption of the light-emitting panel is saved, the circuit layout is simplified, and the cost is reduced, thereby facilitating thinning and narrowing the border of the light-emitting panel.
In an exemplary embodiment,
It is to be understood that
With continued to
It is to be noted that the output terminal of each stage of shift register 161 may be electrically connected to more than one scan signal line 13. The output terminal of the same stage of shift register 161 may be electrically connected to multiple scan signal lines 13 that may be adjacent to each other or spaced apart from each other.
In an exemplary embodiment, with continued to
It is to be understood that when a shift register circuit 16 is disposed in the first border 1021 and the second border 1022 separately, the shift register circuit 16 in the first border 1021 and the shift register circuit 16 in the second border 1022 may be connected to different scan signal lines 13 to provide scan signals for the scan signal lines 13 at different times. Exemplarily, the shift register circuit 16 in the first border 1021 is electrically connected to the scan signal lines 13 in the odd-numbered rows, and the shift register circuit 16 in the second border 1022 is electrically connected to the scan signal lines 13 in the even-numbered rows so that the circuit layout is more reasonable, mutual interference is avoided, and narrowing the border of the display panel is facilitated. Alternatively, the shift register circuit 16 in the first border 1021 and the shift register circuit 16 in the second border 1022 may be connected to the same scan signal line 13 (see
In addition, the constant-current circuit 15 is provided in the third border 1023 so that the constant-current circuit 15 is prevented from being provided in the same border as the shift register circuit 16, which is beneficial to narrowing the border. Multiple output terminals of the constant-current circuit 15 are respectively electrically connected to the data signal lines 14. When the scanning signals respectively supplied from the scan signal lines 13 control the first switch units 12 to be turned on, the current output by the constant-current circuit 15 is supplied to the light-emitting units 11 through the data signal lines 14 and the first switch units 12, and drives the light-emitting units 11 to emit light under the action of the voltage supplied from the first supply voltage terminal V1.
In an exemplary embodiment, with continued to
In an example, the driver chip 17 may be disposed in the third border 1023, and the constant-current circuit 15 is integrated in the driver chip 17 to simplify the circuit layout and facilitate narrowing the border of the light-emitting panel. In addition, the driver chip 17 may be electrically connected to the first supply voltage terminal V1 and supply voltage signal to the first supply voltage terminal V1, but is not limited thereto.
It should be noted that driver chip 17 may be bonded on the light-emitting panel. The bonding technique includes, but is not limited to, Chip on Glass (COG), Chip on FPC (COF), Tape Automated Bonding (TAB), or the like.
In an exemplary embodiment, with continued to
In an example, when the first supply voltage terminal V1 is a constant-voltage output terminal, the voltage signal supplied to the light-emitting unit 11 is a constant voltage signal. The specific voltage value is not limited by the embodiment of the present disclosure, and may be supplied by a power module in the driver chip 17. At the same time, the output terminal of the constant-current circuit 15 includes multiple first output terminals out1 for outputting adjustable currents, that is, the constant-current circuit 15 may output current of any value. In this manner, based on the luminances required by the light-emitting units 11, the values of the currents output by the constant-current circuit 15 are different to drive the light-emitting units 11 to emit different luminances. At the same time, since the light-emitting panel does not need to provide an additional drive circuit, the power consumption of the light-emitting panel can be reduced.
In another alternative embodiment,
In an example, the constant-current circuit 15 outputs a constant drive current signal through the second output terminals out2 and supplies the constant drive current signal to the pulse-width modulation circuits 18. Under the control of a pulse-width modulation circuit 18, the duty ratio of a respective drive current signal can be adjusted, that is, the value of the equivalent output current of the pulse-width modulation circuit 18 can be changed, and then the adjusted current signal is transmitted to the data signal line 14. In this manner, when the first switch unit 12 is turned on, the light-emitting unit 11 is enabled to light-emitting display under the action of the fixed voltage signal provided by the constant-voltage output terminal and the current signal output by the pulse-width modulation circuit 18 so that light-emitting display of different luminances can be enabled in the case of low power consumption of the light-emitting panel.
In an exemplary embodiment,
In an example, the second switch unit 181 may be switch transistor, and for example may be a P-type switch transistor or an N-type switch transistor, which is not limited by the embodiment of the present disclosure. The comparison circuit 182 compares the received data signal supplied from the data signal terminal DATA and the swept-frequency signal supplied from the swept-frequency signal terminal SWEEP, and outputs a switch control signal to control the turn-on or turn-off of the second switch unit 181 so that the second switch unit 181 adjusts the duty ratio of the drive current signal output by the second output terminal out2 under the control of the switch control signal output by the comparison circuit 182. In this manner, the luminance of the light-emitting unit 11 can be adjusted under the condition when the first switch unit 12 is on.
It is to be understood that the data signal of the data signal terminal DATA and the sweep signal of the sweep signal terminal SWEEP may be provided by the driver chip 17. The fixed level terminal VGH (i.e., high level) and VGL (i.e., low level) in the comparison circuit 182 may also be provided by driver chip 17.
It should be noted that the specific values of the data signal of the data signal terminal DATA and the sweep signal of the swept-frequency signal terminal SWEEP are not limited by the embodiment of the present disclosure. For example, the data signal, the constant voltage signal, and the swept-frequency signal may be carrier signals with an adjustable frequency.
In an exemplary embodiment, referring to
It is to be noted that, without special description, the following structure diagram given by the following embodiments will be described in terms of an example to illustrate exemplarily, that is, the output terminal of the constant-current circuit 15 includes multiple first output terminals out1 for outputting adjustable currents.
In an exemplary embodiment,
In an example, a constant-voltage output terminal Vref is used to provide a stable voltage signal vref for the second terminal of the variable resistor R. Because the first terminal of the variable resistor R is grounded, the current flowing through the variable resistor R in sequence is only related to the resistance value of the variable resistor R. That is, the larger the resistance value of the variable resistor R is, the smaller the current of the constant-current circuit 15 output through the first output terminal out1 is. On the contrary, the smaller the resistance value of the variable resistor R is, the larger the current of the constant-current circuit 15 output through the first output terminal out1 is. Thus, the current output by the first output terminal out1 can be adjusted by adjusting the resistance value of the variable resistor R. It is to be understood that if the output terminal of the constant-current circuit 15 is the second output terminal out2 outputting constant current, at this time, the resistance value of the variable resistor R can be kept constant so that the current output by the second output terminal out2 is constant.
In an exemplary embodiment, with continued to
In an exemplary embodiment,
It is to be understood that the current mirror circuit is generally used to reproduce or replicate a reference current (i.e., mirror source current) of a branch in the circuit in other branches as the mirror current. There may be a proportional relationship between the mirror source current and the mirror current, and the proportion is only related to the channel size of the parameter of the transistor inside the current mirror circuit. In an example, the sum of all mirror currents may be made equal to the mirror source current. In this manner, a current mirror circuit enables a source current (i.e., mirror source current) to output multiple stable currents (i.e., mirror currents) at the same time, and then the multiple stable currents are transmitted to the data signal lines 14 by multiple output terminals of the constant-current circuit 15. The circuit structure is simple and easy to implement, the output current is stable and non-harmonic, thereby facilitating saving power consumption of the light-emitting panel.
In an exemplary embodiment, with continued to
In an example, the current on the general branch circuit 151 is I0, and the current on the constant-current branch circuit 152 is Ii, where n represents the total number of constant-current branch circuits 152, and the value of i is an integer greater than or equal to 1 and less than or equal to n. At this time, the current I0 on the general branch circuit 151 and the current Ii on the constant-current branch circuits 152 satisfy the formula
that is, the sum of current Ii of multiple constant-current branch circuits 152 is equal to current I0 on the general branch circuit 151. In this manner, only by changing the value of the current I0 on the general branch circuit 151, the object of adjusting the current on multiple constant-current branch circuits 152 can be achieved, that is, to adjust the value of the current output by the output terminal of the constant-current circuit 15, thereby achieving the object of reducing power consumption of the light-emitting panel. Moreover, the circuit structure is simple, thereby facilitating the circuit layout and narrowing the border of the light-emitting panel.
In an exemplary embodiment,
In an example, under the action of the second supply voltage terminal V2, I0 is generated by the first resistor R1, and the resistance value of the first resistor R1 is not limited by the embodiment, and can be set according to actual requirements. Then, according to the number of the constant-current branch circuits 152, the number of the second triodes Q2 may be different. All of the second triodes Q2 may be identical or different, which is not limited by the embodiment of the present disclosure. It is to be understood that when all of the second triodes Q2 are identical, the current corresponding to each constant-current branch circuit 152 may be identical, so that the light-emitting units 11 electrically connected to the scan signal line 13 in the same column receive the same current output by the constant-current circuit 15 when the first switch units 12 are turned on, and thus have the same luminance.
In another embodiment, since the luminance measured at the edge of the display region at the light-emitting panel is lower than the luminance at the center position, the current transmitted by the data signal line 14 near the edge of the display region 101 of the light-emitting panel may be made larger than the current transmitted by the data signal line 14 at the center position of the display region 101 to increase the evenness of the display of the light-emitting panel. Thus, by varying the channel sizes of the second transistors Q2 electrically connected to respective data signal lines 14, the current output by the constant-current circuit 15 to the data signal lines 14 near the edge of the display region 101 of the light-emitting panel is larger than the current output to the data signal line 14 at the center position of the display region 101.
It is to be understood that the sum of the currents of all the constant-current branch circuits 152 in the above-mentioned embodiments is constant, i.e., the constant I0. Thus, the current I0 on the general branch circuit 151 may be determined by varying the resistance value of the first resistor R1 or the voltage value supplied by the second supply voltage terminal V2. However, in practical applications, limited to the actual value of the second supply voltage terminal V2 and the resistance value of the first resistor R1, the maximum value of the current I0 on the general branch circuit 152 is also relatively limited. When the number of constant-current branch circuits 152 is large and the light-emitting panel is required to provide a large luminance, it is difficult to ensure that the current output by the constant-current circuit 15 to each data signal line 14 is large enough.
In an exemplary embodiment,
In an example, the input terminal and output terminal of the amplifier circuit 1511 are connected to the general branch circuit 151. The energy source of the amplifier circuit may be provided by an external power. The current I0 on the general branch circuit 151 may be amplified to the desired current value by the amplifier circuit 1511. The embodiment of the present disclosure set no limits on the specific circuit structure of the amplifier circuit 1511 and the amplification factor of the amplifier circuit 1511. The specifics may be set according to actual requirements. Exemplarily, the amplifier circuit 1511 may employ a conventional current amplifier.
In an exemplary embodiment,
The specific number of multiplexer 19 and the number of output terminal of multiplexer 19 are not limited by the embodiment of the present disclosure, and may be designed according to actual requirements.
In an exemplary embodiment, with continued to
It is to be understood that when a light-emitting panel is used as a backlight, at the edge of the light-emitting panel, the edges of the fluorescent film layer and the quantum film layer disposed upon the light-emitting unit are ineffective, the edge luminance of the light-emitting panel is lower, that is, the luminance of the first light-emitting unit 111 is less than the luminance of the second light-emitting unit 112, resulting in uneven display of the light-emitting panel. In this regard, by setting that the drive current of the first light-emitting unit 111 being greater than the drive current of the second light-emitting unit 112, the luminance difference between the first light-emitting unit 111 and the second light-emitting unit 112 can be reduced, and the light-emitting display evenness of the light-emitting panel can be improved.
In an exemplary embodiment, with continued reference to
In another exemplary embodiment, the light-emitting unit 11 includes multiple light-emitting elements arranged in an array.
Exemplarily,
It is to be noted that the specific arrangement and arrangement density of the light-emitting elements in the light-emitting unit 11 are not limited by the embodiment of the present disclosure and may be set according to actual requirements.
In an exemplary embodiment, in any of the above-described embodiments, the light-emitting element includes a submillimeter light-emitting diode or a micro light-emitting diode so that the light-emitting panel has advantages such as low power consumption, high luminance, ultra-high resolution and color saturation, fast reaction speed, super power saving, long service life, high efficiency, and the like.
Based on the same inventive concept, an embodiment of the present disclosure provides a driving method of a light-emitting panel, suitable for the light-emitting panel in any of the above-mentioned embodiments.
In S101, a to-be-displayed grayscale value of the light-emitting unit is acquired.
In S102, a drive current required by the light-emitting unit is determined according to the grayscale value.
In S103, a constant-current circuit is controlled according to the magnitude of the drive current to supply a current to a corresponding data signal line.
In S104, a first switch unit is controlled to turn on so that the light-emitting unit emits light.
As shown in
In an example, after obtaining the to-be-displayed grayscale value of the light-emitting unit, based on the correspondence between the grayscale value displayed by the light-emitting unit and the drive current required by the light-emitting unit, the drive current of the light-emitting unit can be obtained, in other words, the drive current of the light-emitting unit is the current that the constant-current circuit needs to provide to the corresponding data signal line for displaying the to-be-displayed grayscale value. Then the constant-current circuit is controlled to work to supply stable currents to the corresponding data signal lines. When the scanning signal provided by the scan signal line drives the first switch unit to be turned on, the drive current on the data signal line is transmitted to the light-emitting unit through the first switch unit to drive the light-emitting unit to emit light, thereby achieving the effect of saving power consumption.
In an exemplary embodiment, referring to
In an exemplary embodiment, referring to
In an exemplary embodiment, along the direction from middle to two sides of the light-emitting panel, the currents output by the constant-current circuit to the data signal lines gradually increases.
It is to be understood that due to various factors such as preparation technique, the display luminance of the light-emitting panel of the edge region is generally lower than the display luminance of the intermediate region, resulting in unevenness of the display luminance, thereby affecting display effect.
Along the direction from middle to two sides of the light-emitting panel, the currents output by the constant-current circuit to the data signal lines gradually increases so that the luminance of the edge of the light-emitting panel can be gradually increased, and the display luminance at each position can smoothly transition, thereby avoiding the obvious light and dark boundary caused by abrupt luminance change, thereby improving the overall display evenness.
Based on the same inventive concept, an embodiment of the present disclosure also provides a display device including the light-emitting panel in any of the above-described embodiments. The display device includes the light-emitting panel according to any of embodiments of the present disclosure. Therefore, the display device according to the embodiment of the present disclosure includes the features of the light-emitting panel according to any of embodiments of the present disclosure, and can achieve the advantageous effect of the light-emitting panel according to any of embodiments of the present disclosure. Reference to the description of the light-emitting panel of embodiments of the present disclosure can be made when it comes to the same parts, and details are not described herein.
The light-emitting panel according to the embodiment of the present disclosure may be a display panel directly performing image display, or may be a backlight panel providing light for other display panel, which is not limited in the embodiment of the present disclosure.
In an alternative embodiment,
The above-mentioned specific embodiments do not constitute a limitation on the protection scope of the present disclosure. It is to be understood by those skilled in the art that various modifications, combinations, subcombinations, and substitutions may be made according to design requirements and other factors. Any modifications, equivalent replacements, improvements and the like within the spirit and principle of the present disclosure shall fall within the protection scope of the present disclosure.
| Number | Date | Country | Kind |
|---|---|---|---|
| 202211008776.9 | Aug 2022 | CN | national |
| Number | Name | Date | Kind |
|---|---|---|---|
| 20190235336 | Uehata | Aug 2019 | A1 |
| 20200134277 | Lin | Apr 2020 | A1 |
| 20220335905 | Miyata | Oct 2022 | A1 |
| Number | Date | Country |
|---|---|---|
| 100353400 | Dec 2007 | CN |
| 212135912 | Dec 2020 | CN |
| Number | Date | Country | |
|---|---|---|---|
| 20230122051 A1 | Apr 2023 | US |
