Patent Publication Number: US-10783829-B2

Title: Display panel and display device with uniform brightness

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to a Chinese patent application No. 201810386273.2 filed on Apr. 26, 2018, the disclosure of which is incorporated herein by reference in its entirety. 
     TECHNICAL FIELD 
     The present disclosure relates to a technical field of displays and, in particular, to a display panel and a display device. 
     BACKGROUND 
     At present, display panels are widely used in electronic devices such as mobile phones, tablet computers, and information query machines in public lobbies. A display panel includes light-emitting components and pixel drive circuits coupled to the light-emitting components. A pixel drive circuit drives a light-emitting component to emit light. The display panel usually achieves a full color display by mixing red, green and blue sub-pixels into any other colors among the light-emitting components. 
     However, the pixel drive circuits in the existing display panel do not have a reasonable design. In a low gray scale display state, the display panel has poor uniformity, which impacts the display quality and the user experience of the display panel. 
     SUMMARY 
     The present disclosure provides a display panel and display device to improve display uniformity of the display panel in a low gray scale display state, and display quality and user experience of the display panel. 
     In a first aspect, embodiments of the present disclosure provide a display panel. The display panel includes multiple sub-pixels arranged in an array. Each of the sub-pixels includes a pixel drive circuit and a light-emitting component. The pixel drive circuit is configured to provide a driving current for the light-emitting component. The light-emitting component is configured to emit light in response to the driving current. 
     The sub-pixels include first type sub-pixels and second type sub-pixels. The difference between a starting voltage of the light-emitting component of a first type sub-pixel and a starting voltage of the light-emitting component of a second type sub-pixel is greater than a preset value. 
     The first type sub-pixel includes a first voltage-regulating module. The first voltage-regulating module is connected between the pixel drive circuit and the light-emitting component of the first type sub-pixel and is configured to increase a voltage between two ends of the light-emitting component. Additionally or alternatively, the second type sub-pixel includes a second voltage-regulating module. The second voltage-regulating module is connected between the pixel drive circuit and a first end of the light-emitting component of the second type sub-pixel and is configured to reduce a voltage between the first end and a second end of the light-emitting component. 
     In a second aspect, embodiments of the present disclosure provide a display device. The display device includes the display panel of any one of the embodiments of the present disclosure. 
     In the present disclosure, a first type sub-pixel includes a first voltage-regulating module, which is connected between a pixel drive circuit and a first end of a light-emitting component in the first type sub-pixel and is configured to increase a voltage between the first end and a second end of the light-emitting component; and/or, a second type sub-pixel includes a second voltage-regulating module, which is connected between a pixel drive circuit and a light-emitting component in the second type sub-pixel and is configured to reduce the voltage between the first end and the second end of the light-emitting component, thereby reducing the display difference brought by the difference between the starting voltage of the light-emitting component in the first type sub-pixel and the starting voltage of the light-emitting component in the second type sub-pixel. This achieves an effect that the brightness of the light-emitting components in sub-pixels tends to be consistent in the case where the first type sub-pixel and the second type sub-pixel adopt the same pixel drive circuit and the same driving current, thereby improving the display effect of the display panel in the low gray scale display state, and display quality and user experience of the display panel. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a structural diagram of a display panel according to an embodiment of the present disclosure; 
         FIG. 2  is a circuit diagram of a first type sub-pixel according to an embodiment of the present disclosure; 
         FIG. 3  is a circuit diagram of a second type sub-pixel according to an embodiment of the present disclosure; 
         FIG. 4  is a lightness-to-voltage (L-V) curve graph of a light-emitting component of a display panel according to an embodiment of the present disclosure; 
         FIG. 5  is a circuit diagram of another first type sub-pixel according to an embodiment of the present disclosure; 
         FIG. 6  is a circuit diagram of another second type sub-pixel according to an embodiment of the present disclosure; 
         FIG. 7  is a circuit diagram of yet another second type sub-pixel according to an embodiment of the present disclosure; 
         FIG. 8  is a circuit diagram of yet another first type sub-pixel according to an embodiment of the present disclosure; 
         FIG. 9  is a circuit diagram of a pixel drive circuit according to an embodiment of the present disclosure; 
         FIG. 10  is a diagram illustrating a driving timing sequence according to an embodiment of the present disclosure; 
         FIG. 11  is a structural diagram of another display panel according to an embodiment of the present disclosure; and 
         FIG. 12  is a structural diagram of a display device according to an embodiment of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     The present disclosure will be further described in detail in conjunction with the drawings and embodiments. It is to be understood that the embodiments set forth below are intended to illustrate and not to limit the present disclosure. Additionally, it is to be noted that to facilitate description, only part, not all, of structures related to the present disclosure are illustrated in the drawings. 
       FIG. 1  is a structural diagram of a display panel according to an embodiment of the present disclosure. Referring to  FIG. 1 , the display panel  1  includes multiple sub-pixels arranged in array. Each sub-pixel includes a pixel drive circuit and a light-emitting component. The pixel drive circuit is configured to provide a driving current for the light-emitting component. The light-emitting component is configured to emit light in response to the driving current. The sub-pixels include first type sub-pixels  11  and second type sub-pixels  12  having different starting voltages. The difference between a starting voltage of the light-emitting component of a first type sub-pixel  11  and a starting voltage of the light-emitting component of a second type sub-pixel  12  is greater than a preset value.  FIG. 2  is a circuit diagram of a first type sub-pixel according to an embodiment of the present disclosure.  FIG. 3  is a circuit diagram of a second type sub-pixel according to an embodiment of the present disclosure. Referring to  FIGS. 2 and 3 , the first type sub-pixel  11  includes a first voltage-regulating module  330 . The first voltage-regulating module  330  is connected between the pixel drive circuit  100  and a first end of the light-emitting component  320  of the first type sub-pixel  11  and is configured to increase a voltage between the first end and a second end of the light-emitting component  320 . Additionally or alternatively, the second type sub-pixel  12  includes a second voltage-regulating module  430 . The second voltage-regulating module  430  is connected between the pixel drive circuit  100  and a first end of the light-emitting component of the second type sub-pixel  12  and is configured to reduce a voltage between the first end and a second end of the light-emitting component  420 . The starting voltage refers to a voltage value required by the light-emitting component of the sub-pixel when the brightness is 0.1 nit. 
     The present disclosure is described below with reference to an example in which the first type sub-pixel  11  is a blue sub-pixel and the second type sub-pixel  12  is a red sub-pixel or a green sub-pixel. It is to be noted that, in practice, the first type sub-pixel  11  and the second type sub-pixel  12  may have various structures, and are not limited in the present disclosure. 
       FIG. 4  is an L-V curve graph of a light-emitting component of a display panel according to an embodiment of the present disclosure. Referring to  FIG. 4 , a curve  510  is the L-V curve of the light-emitting component of the blue sub-pixel; a curve  520  is the L-V curve of the light-emitting component of the red sub-pixel; a curve  530  is the L-V curve of the light-emitting component of the green sub-pixel. It can be seen that starting voltages of light-emitting components of the blue sub-pixel, the red sub-pixel and the green sub-pixel are different. The starting voltage of the light-emitting component of the green sub-pixel is close to the starting voltage of the light-emitting component of the red sub-pixel, and is about 2.4V. The starting voltage of the light-emitting component of the blue sub-pixel is higher, and is about 2.6 V. The brightness of the light-emitting component of the sub-pixel relates to not only the driving current passing through the light-emitting component, but also a voltage between two ends of the light-emitting component. Under the condition that the same brightness is generated, the voltage between two ends of the light-emitting component of the blue sub-pixel is higher than the voltage between two ends of the light-emitting components of the red sub-pixel and the green sub-pixel. Therefore, though the same driving current and voltage are provided to the sub-pixels of the display panel  1 , the brightness of the light-emitting components of respective sub-pixels is not exactly the same. 
     However, in most cases, the blue sub-pixel, the red sub-pixel and the green sub-pixel in the existing display panel adopt the same pixel drive circuit  100 . Based on the above analysis, the same driving current is provided to respective sub-pixels of the existing display panel, generating different levels of brightness and reducing the display uniformity of the display panel. Especially, in a low gray scale display state, the difference of the display brightness of different sub-pixels has more influence on display color; and the uniformity of display images is poor, impacting the display quality and the user experience of the display panel. 
     According to the configuration of an embodiment of the present disclosure, the first type sub-pixel  11  includes the first voltage-regulating module  330 , the first voltage-regulating module  330  is connected between the pixel drive circuit  100  and a first end of the light-emitting component of the first type sub-pixel  11  and is configured to increase a voltage between the first end and a second end of the light-emitting component; and/or, the second type sub-pixel  12  includes a second voltage-regulating module  430 , the second voltage-regulating module  430  is connected between the pixel drive circuit  100  and a first end of the light-emitting component of the second type sub-pixel  12  and is configured to reduce a voltage between the first end and a second end of the light-emitting component, thereby reducing display difference brought by the difference between the starting voltage of the light-emitting component in the first type sub-pixel  11  and the starting voltage of the light-emitting component of the second type sub-pixel  12 . Therefore, the embodiment of the present disclosure may enable that the brightness of the light-emitting components in sub-pixels tends to be consistent in the case where the first type sub-pixel  11  and the second type sub-pixel  12  to adopt the same pixel drive circuit  100  and the same driving current, thereby improving the display uniformity of the display panel  1 , the display effect of the display panel  1  in the low gray scale display state, and display quality and user experience of the display panel  1 . 
     On the basis of the above technical solutions,  FIG. 5  is a circuit diagram of another first type sub-pixel according to an embodiment of the present disclosure.  FIG. 6  is a circuit diagram of another second type sub-pixel according to an embodiment of the present disclosure. Referring to  FIG. 5 , in the first type sub-pixel  11 , the first voltage-regulating module  330  includes a first transistor  331 . A first electrode of the first transistor  331  is electrically connected to an output end of the pixel drive circuit  100 , and a second electrode of the first transistor  331  is electrically connected to the first end of the light-emitting component  320 . The second end of the light-emitting component  320  is electrically connected to a first power supply voltage signal line PVEE. A gate electrode of the first transistor  331  is connected to the first electrode of the first transistor  331 . Additionally or alternatively, referring to  FIG. 6 , in the second type sub-pixel  12 , the second voltage-regulating module  430  includes a first transistor  431 . A first electrode of the first transistor  431  is electrically connected to an output end of the pixel drive circuit  100 , and a second electrode of the first transistor  431  is electrically connected to a first end of the light-emitting component  420 . The second end of the light-emitting component  420  is electrically connected to the first power supply voltage signal line PVEE. A gate electrode of the first transistor  431  is connected to the first electrode of the first transistor  431 . 
     According to the configuration of an implementation mode, the first voltage-regulating module  330  and/or the second voltage-regulating module  430  includes the first transistor. The gate electrode of the first transistor is electrically connected to the first electrode of the first transistor. In this way, the first transistor is connected to form a structure of a diode. The diode may increase the voltage between the two ends of the light-emitting component of the first type sub-pixel  11 , or reduce the voltage between the two ends of the light-emitting component of the second type sub-pixel  12 , which is beneficial for reducing the display difference brought by the difference between the starting voltage of the light-emitting component in the first type sub-pixel  11  and the starting voltage of the light-emitting component in the second type sub-pixel  12 , improving the uniformity of display images in the low gray scale display state, and improving the display quality of the display panel  1 . In addition, the structure of the first transistor may be the same with other transistors in the display panel  1 , and may adopt the same manufacturing process, thereby saving the manufacturing process of the first voltage-regulating module  330  and the second voltage-regulating module  430 . 
     Referring to  FIG. 5 , the first transistor  331  in the first voltage-regulating module  330  is a P-type transistor. The threshold voltage of the P-type transistor has a negative value. The P-type transistor is disposed between the pixel drive circuit  100  and the light-emitting component  320  of the first type sub-pixel  11 , which is equivalent to the increase in the voltage at the first end of the light-emitting component  320  of the first type sub-pixel  11 . This is beneficial for reducing the display difference brought by the difference between the starting voltage of the light-emitting component in the first type sub-pixel  11  and the starting voltage of the light-emitting component in the second type sub-pixel  12 , thereby improving display uniformity of the display panel  1  in the low gray scale display state, and the display quality of the display panel  1 . 
     Referring to  FIG. 6 , the first transistor in the second voltage-regulating module  430  is an N-type transistor. The threshold voltage of the N-type transistor has a positive value. The N-type transistor is disposed between the pixel drive circuit  100  and the light-emitting component  420  of the second type sub-pixel  12 , which is equivalent to the reduction in the voltage at the first end of the light-emitting component  420  of the second type sub-pixel  12 . This is beneficial for reducing the display difference brought by the difference between the starting voltage of the light-emitting component in the first type sub-pixel  11  and the starting voltage of the light-emitting component in the second type sub-pixel  12 , thereby improving display uniformity of the display panel  1  in the low gray scale display state, and the display quality of the display panel  1 . 
     On the basis of the above technical solutions, the threshold voltage VD of the first transistor, the starting voltage VB of the light-emitting component of the first type sub-pixel  11  and the starting voltage VRG of the light-emitting component of the second type sub-pixel  12  satisfy a formula: |VB-VRG|&gt;|VB-VRG-VD|. 
     The threshold voltage VD of the first transistor is configured to satisfy the formula, which actually reduces the difference between the starting voltages of the light-emitting components in the first type sub-pixel  11  and the second type sub-pixel  12 , which is beneficial for reducing the display difference brought by the difference between the starting voltages of the light-emitting components in the first type sub-pixel  11  and the second type sub-pixel  12 , and improving display uniformity of the display panel  1 , thereby improving the display uniformity of the display panel  1  in the low gray scale display state, and the display quality of the display panel  1 . 
     On the basis of the above technical solutions, in an embodiment, the threshold voltage of the first transistor is comprised between 0.2 V and 1.0 V. This further reduces the display difference brought by the difference between the starting voltages of the light-emitting components in the first type sub-pixel  11  and the second type sub-pixel  12 , and improves the display quality of the display panel  1 . 
     On the basis of the above technical solutions, in an embodiment, the threshold voltage of the first transistor is 0.3 V. This reduces the display difference brought by the difference between the starting voltages of the light-emitting components in the first type sub-pixel  11  and the second type sub-pixel  12 , and improves the display quality of the display panel  1 . 
       FIG. 7  is a circuit diagram of yet another second type sub-pixel according to an embodiment of the present disclosure. Referring to  FIG. 7 , on the basis of the above technical solutions, in an embodiment, the second voltage-regulating module  430  includes a first diode  432 . An anode of the first diode  432  is electrically connected to an output end of the pixel drive circuit  100 . A cathode of the first diode  432  is electrically connected to the first end of the light-emitting component  420 . The second end of the light-emitting component  420  is electrically connected to the first power supply voltage signal line PVEE. The threshold voltage of the first diode  432  has a positive value. The disposeal of the first diode  432  may reduce the voltage of the two ends of the light-emitting component  420  of the second type sub-pixel  12 , which is beneficial for reducing the display difference brought by the difference between the starting voltages of the light-emitting components in the first type sub-pixel  11  and the second type sub-pixel  12 , thereby improving display uniformity of the display panel  1  in the low gray scale display state, and the display quality of the display panel  1 . 
       FIG. 8  is a circuit diagram of yet another first type sub-pixel according to an embodiment of the present disclosure. Referring to  FIG. 8 , on the basis of the above technical solutions, in an embodiment, the second voltage-regulating module  430  includes a first resistor  433 . The first resistor  433  is connected between an output end of the pixel drive circuit  100  and a first end of the light-emitting component  420 . A second end of the light-emitting component  420  is electrically connected to the first power supply voltage signal line PVEE. An output voltage of the pixel drive circuit  100  passes through the first resistor  433 , and generates a voltage drop between two ends of the first resistor  433  to reduce the voltage between the two ends of the light-emitting component  420  of the second type sub-pixel  12 . This is beneficial for reducing the display difference brought by the difference between the starting voltages of the light-emitting components in the first type sub-pixel  11  and the second type sub-pixel  12 , thereby improving display uniformity of the display panel  1  in the low gray scale display state, and the display quality of the display panel  1 . 
     On the basis of the above technical solutions, the difference between the starting voltage of the light-emitting component of the first type sub-pixel  11  and the starting voltage of the light-emitting component of the second type sub-pixel  12  is greater than a preset value. The preset value may be greater than or equal to 0.1 V. It can be seen from the foregoing analysis that the greater the difference between the starting voltages of the light-emitting components in the first-type sub-pixel  11  and the second-type sub-pixel  12  is, the worse the display uniformity of the display panel  1  is. Such configuration of the display panel  1 , on one hand, may improve the uniformity of the display panel  1 , and on the other hand, may reduce manufacturing costs of the display panel  1 . 
     On the basis of the above technical solutions, the first type sub-pixel  11  may include a blue sub-pixel and the second type sub-pixel  12  may include a red sub-pixel and/or a green sub-pixel. It can be seen from the foregoing analysis that the starting voltages of the light-emitting components of the red sub-pixel and the green sub-pixel are low, and the starting voltage of the light-emitting component of the blue sub-pixel is high. Such configuration of the display panel  1  reduces the display difference brought by the difference between the starting voltage of the light-emitting component in the blue sub-pixel and the starting voltage of the light-emitting components in the red sub-pixel and the green sub-pixel, thereby improving the uniformity of the display images in the low gray scale display state, and the display quality of the display panel  1 . 
       FIG. 9  is a circuit diagram of a pixel drive circuit according to an embodiment of the present disclosure. Referring to  FIG. 9 , on the basis of the above technical solutions, the pixel drive circuit  100  includes a second transistor M 2 , a third transistor M 3 , a fourth transistor M 4 , a fifth transistor M 5 , a sixth transistor M 6 , a seventh transistor M 7  and a storage capacitor Cst. The second transistor M 2  has a first electrode electrically connected to a data line DATA, a second electrode electrically connected to a first electrode of the third transistor M 3 , and a gate electrode electrically connected to a first scanning line S 1 . The fourth transistor M 4  has a first electrode electrically connected to a second electrode of the third transistor M 3 , a second electrode electrically connected to the gate electrode of the third transistor M 3 , and a gate electrode electrically connected to the first scanning line S 1 . The fifth transistor M 5  has a first electrode electrically connected to a second power supply voltage signal line Vref, a second electrode electrically connected to the gate electrode of the third transistor M 3 , and a gate electrode electrically connected to a second scanning line S 2 . The sixth transistor M 6  has a first electrode electrically connected to the second electrode of the third transistor M 3 , a second electrode electrically connected to a first end of a voltage-regulating module, and a gate electrode electrically connected to a light-emitting signal line Emit. The voltage-regulating module may be the first voltage-regulating module  330  and/or the second voltage-regulating module  430 . The second electrode of the sixth transistor M 6  may be the output end  101  of the pixel drive circuit  100 . The seventh transistor M 7  has a first electrode electrically connected to a third power supply voltage signal line PVDD, a second electrode electrically connected to the first electrode of the third transistor M 3 , and a gate electrode electrically connected to the light-emitting signal line Emit. A first electrode of the storage capacitor Cst is electrically connected to the gate of the third transistor M 3 , and a second electrode of the storage capacitor Cst is electrically connected to the first electrode of the third transistor M 3 . 
       FIG. 10  is a diagram illustrating a driving timing sequence according to an embodiment of the present disclosure. A working process of the pixel drive circuit  100  provided by the embodiment of the present disclosure is exemplarily described below in conjunction with  FIGS. 9 and 10 . S-S 1  represents a first scanning signal on the first scanning line S 1 . S-S 2  represents a second scanning signal on the second scanning line S 2 . S-Emit represents a light-emitting signal on the light-emitting signal line Emit. Each transistor is a P-type transistor. A third power supply voltage signal on the third power supply voltage signal line PVDD is high-level. A first power supply voltage signal on the first power supply voltage signal line PVEE is low-level. The working process of the pixel drive circuit  100  includes stages described below. 
     In stage t 1 , the light-emitting signal S-Emit is low-level. The sixth transistor M 6  and the seventh transistor M 7  are turned on. When a last stage is finished, the gate electrode of the third transistor M 3  is high-level and the third transistor M 3  is turned off. Since the seventh transistor M 7  is turned on, the third power supply voltage signal on the third power supply voltage signal line PVDD is written into the first electrode of the third transistor M 3 , that is, the source electrode of the third transistor M 3 . This stage is also called a turned-off stage. 
     In stage t 2 , the light-emitting signal Emit is high-level. The sixth transistor M 6  and the seventh transistor M 7  are turned off. The second scanning signal S-S 2  is low-level. The fifth transistor M 5  is turned on. A second power supply voltage signal on the second power supply voltage signal line Vref is written into the gate electrode of the third transistor M 3  and the first electrode of the storage capacitor Cst. At this stage, the second power supply voltage signal on the second power supply voltage signal line Vref may be a low-level signal in order to reset the voltage at the gate electrode of the third transistor M 3  and the voltage at the first electrode of the storage capacitor Cst. This ensures that in a next stage, the third transistor M 3  is turned on and a data signal may be written into the gate electrode of the third transistor M 3 . This stage is also called a reset stage. 
     In stage t 3 , the light-emitting signal Emit is high-level. The sixth transistor M 6  and the seventh transistor M 7  are turned off. The second scanning signal S-S 2  is high-level. The fifth transistor M 5  is turned off. The first scanning signal S-S 1  is low-level. The second transistor M 2  and the fourth transistor M 4  are turned on. The data signal on the data line DATA passes through the second transistor M 2 , the third transistor M 3  and the fourth transistor M 4  sequentially and is written into the gate electrode of the third transistor M 3  and the first electrode of the storage capacitor Cst. The voltage at the gate electrode of the third transistor M 3  is gradually increasing until a difference between the voltage at the gate electrode and the voltage at the source electrode of the third transistor M 3  is equal to a threshold voltage of the third transistor M 3 . At this time, the third transistor M 3  is turned off. The voltage at the gate electrode of the third transistor M 3  stays unchanged. The voltage at the gate electrode of the third transistor M 3 , that is, a voltage at a first node N 1  satisfies V 1 =V data +V th , where V data  is a voltage value of the data signal on the data line, V th  is the threshold voltage of the third transistor M 3 . 
     In stage t 4 , which is also called a light-emitting stage, the light-emitting signal Emit is low-level. The sixth transistor M 6  and the seventh transistor M 7  are turned on. The first scanning signal S-S 1  is high-level. The second transistor M 2  and the fourth transistor M 4  are turned off. The third transistor M 3  and the fifth transistor M 5  are also turned off. A leakage current of the third transistor M 3 , that is, a driving current generated by the third transistor M 3  drives a light-emitting component  11  to emit light. The driving current I d  satisfies the following formula: 
     
       
         
           
             
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     V PVDD  is a voltage value of the third power supply voltage on the third power supply voltage signal line PVDD, that is, a voltage value at a second node N 2 . It can be seen that the driving current I d  generated by the third transistor M 3  is irrelevant to the threshold voltage V th  of the third transistor M 3 . The display quality of the display panel  1  is further improved. 
     In the embodiment of the present disclosure, the second transistor M 2 , the third transistor M 3 , the fourth transistor M 4 , the fifth transistor M 5 , the sixth transistor M 6  and the seventh transistor M 7  may all be P-type transistors. In other implementation modes of the embodiment of the present disclosure, the second transistor M 2 , the third transistor M 3 , the fourth transistor M 4 , the fifth transistor M 5 , the sixth transistor M 6  and the seventh transistor M 7  may all be N-type transistors. In a case where the driving transistor is an N-type transistor, a voltage difference between a voltage at the gate electrode and a voltage at the source electrode of the driving transistor is required to be less than a negative value of a threshold voltage of the driving transistor. 
     On the basis of the above technical solutions, in an embodiment, a difference between a voltage on the third power supply voltage signal line PVDD and a voltage on the first power supply voltage signal line PVEE is greater than or equal to 9 V. Research shows that the greater the difference between the voltage on the third power supply voltage signal line PVDD and the voltage on the first power supply voltage signal line PVEE is, the smaller the difference of the display brightness of sub-pixels is. A cross-voltage between the third power supply voltage signal line PVDD and the first power supply voltage signal line PVEE is configured to be greater than or equal to 9 V, further improving the display uniformity of the display panel  1 . 
       FIG. 11  is a structural diagram of another display panel according to an embodiment of the present disclosure. Referring to  FIG. 11 , on the basis of the above technical solutions, the display panel  1  is an organic light-emitting diode display panel to improve the display uniformity and display effect of the organic light-emitting diode display panel. 
     In the above technical solutions, the first type sub-pixel  11  and the second type sub-pixel  12  each includes a light-emitting component  600 . The light-emitting components  600  of the first type sub-pixel  11  and the second type sub-pixel  12  have a same structure and have multiple structural forms. Detailed examples are given below, but not intended to limit the present disclosure. 
     Referring to  FIG. 11 , a light-emitting component includes a first electrode  610 , a second electrode  620 , a light-emitting layer  650  and at least one first common layer  630 . The second electrode  620  and the first electrode  610  are disposed opposite to each other. The light-emitting layer  650  is disposed between the first electrode  610  and the second electrode  620 . The at least one first common layer  630  is disposed between the first electrode  610  and the light-emitting layer  650 . Multiple light-emitting components  600  share the first common layer  630 , and the first electrode  610  is a first end of the light-emitting component  600 . Because the difference between a starting voltage of the light-emitting components  600  in the first type sub-pixels  11  and a starting voltage of the light-emitting components  600  in the second type sub-pixels  12  is greater than a preset value, when the first type sub-pixels  11  emit light to display a single color image, electrons and holes in the first common layer  630  form a horizontal leakage current, which makes the light-emitting components  600  in the light-emitting components  600  to emit light accidentally, causing an inference phenomenon of the display color of the display panel  1  and a distorted display image. In the embodiment of the present disclosure, on one hand, under the driving of the same driving current, the brightness of the light-emitting components  600  of the sub-pixels tend to be consistent, improving the display uniformity of the display panel; on the other hand, the horizontal leakage current of the first common layer  630  in the first type sub-pixel  11  and second type sub-pixel  12  is reduced, further improving the display effect of the display panel  1  in the low gray scale display state and the user experience of the display panel  1 . 
     If the first electrode  610  is an anode, the first common layer  630  may be one or more of a hole injection layer, a hole transport layer and an electron blocking layer. If the first electrode  610  is a cathode, the first common layer  630  may be one or more of an electron injection layer, an electron transport layer and a hole blocking layer. This improves mobility of carriers of the light-emitting component  600  and reduces the power consumption of the device. 
     It is to be noted that specific structures of the voltage-regulating module in the above embodiments may be various. Exemplarily, referring to  FIG. 11 , a film layer containing the first voltage-regulating module  330  and/or the second voltage-regulating module  430  is disposed between the pixel drive circuit  100  and the light-emitting component  600 . In other implementation modes, the first voltage-regulating module  330  and the second voltage-regulating module  430  may also be disposed at the same film layer with the transistors of the pixel drive circuit  100 , which is beneficial for reducing the thickness of the display panel  1 , the number of masks and the manufacturing costs of the display panel  1 . 
     An embodiment of the present disclosure further provides a display device.  FIG. 12  is a structural diagram of the display device according to the embodiment of the present disclosure. Referring to  FIG. 12 , the display device includes the display panel of any one of embodiments of the present disclosure. 
     According to the configuration of the display device provided by the present disclosure, a first type sub-pixel includes a first voltage-regulating module, the first voltage regulating module is connected between a pixel drive circuit and a first end of a light-emitting component in the first type sub-pixel and is configured to increase a voltage between the first end and a second end of the light-emitting component; additionally or alternatively, a second type sub-pixel includes a second voltage-regulating module, the second voltage-regulating module is connected between a pixel drive circuit and a first end of a light-emitting component in the second type sub-pixel and is configured to reduce the voltage between the first end and the second end of the light-emitting component, thereby reducing the display difference brought by the difference between starting voltages of the light-emitting components in the first type sub-pixel and the second type sub-pixel. This achieves an effect that the brightness of the light-emitting components in sub-pixels tends to be consistent in the case where the first type sub-pixel and the second type sub-pixel adopt the same pixel drive circuit and the same driving current, thereby improving display uniformity of the display device, the display effect of the display device in the low gray scale display state, and display quality and user experience of the display device. 
     It is to be noted that the above are only preferred 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 and substitutions without departing from the scope of the present disclosure. Therefore, while the present disclosure has been described in detail via 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.