Display panel and display device

Abstract

Embodiments of the present application provide a display panel and a display device, which relate to the technical field of display, and effectively improve the brightness inconsistency and color deviation phenomenon caused by temperature. The display panel comprises a substrate, a plurality of light emitting units on one side of the substrate, wherein the light emitting unit comprises an organic light emitting element and a thermistor, the organic light emitting element comprises a first electrode, a light emitting layer and a second electrode which are stacked in a direction perpendicular to the plane of the substrate, and the thermistor is electrically connected with the first electrode.

Description

Technical Field

[0001] This invention relates to the field of display technology, and more specifically to a display panel and a display device. Background Technology

[0002] Compared with traditional display panels, organic light-emitting diode (OLED) display panels have excellent characteristics such as high brightness, high efficiency, wide viewing angle and fast response speed, and are widely used in various display devices.

[0003] Figure 1 This is a schematic diagram of a display panel structure in the prior art, such as... Figure 1 As shown, this type of display panel uses an organic light-emitting element 101 for light emission. The organic light-emitting element 101 includes an anode 102, a light-emitting layer 103, and a cathode 104 stacked together. Under the drive of an electric field, electrons and holes are injected into the light-emitting layer 103 to recombine and emit light. However, the carrier mobility of the organic light-emitting material forming the light-emitting layer 103 is very sensitive to temperature changes. Even with constant voltage driving, the luminous brightness of the organic light-emitting element 101 will vary at different temperatures. For example, in a low-temperature environment, the carrier mobility of the light-emitting layer 103 decreases due to the low temperature, resulting in a lower luminous current of the organic light-emitting element 101. In a high-temperature environment, the carrier mobility of the light-emitting layer 103 increases due to the high temperature, which in turn leads to a higher luminous current of the organic light-emitting element 101. Consequently, the actual luminous brightness of the organic light-emitting element 101 deviates from the standard brightness at both low and high temperatures, causing a shift in the color coordinates of the white point and resulting in color distortion of the image displayed on the display panel. Summary of the Invention

[0004] In view of this, this application provides a display panel and display device that effectively improves the brightness inconsistency and color deviation caused by temperature.

[0005] In a first aspect, embodiments of this application provide a display panel, including:

[0006] Substrate;

[0007] Multiple light-emitting units are located on one side of the substrate. Each light-emitting unit includes an organic light-emitting element and a thermistor. The organic light-emitting element includes a first electrode, a light-emitting layer, and a second electrode stacked in a direction perpendicular to the plane of the substrate. The thermistor is electrically connected to the first electrode.

[0008] In one embodiment, the first electrode is an anode;

[0009] The thermistor is connected in series with the anode, and the thermistor is a positive temperature coefficient thermistor.

[0010] In one embodiment, at least a portion of the thermistor is located on the side of the first electrode opposite to the light-emitting layer, and the thermistor is disposed adjacent to the first electrode.

[0011] Furthermore, the thermistor also covers the sidewall of the first electrode.

[0012] In one embodiment, the first electrode includes a first light-transmitting sub-electrode, a reflective sub-electrode, and a second light-transmitting sub-electrode stacked in a direction perpendicular to the plane of the substrate, wherein the first light-transmitting sub-electrode is located on the side of the reflective sub-electrode facing away from the light-emitting layer;

[0013] The thermistor is located between the first transparent sub-electrode and the reflective sub-electrode.

[0014] In one embodiment, the first electrode includes a reflective sub-electrode and a light-transmitting sub-electrode stacked in a direction perpendicular to the plane of the substrate, wherein the second light-transmitting sub-electrode is located on the side of the reflective electrode facing the light-emitting layer;

[0015] The thermistor is located on the side of the reflective sub-electrode that faces away from the second light-transmitting sub-electrode, and the thermistor is disposed adjacent to the reflective sub-electrode.

[0016] In one embodiment, the first electrode is a cathode, and the cathodes of the plurality of light-emitting units are independent of each other;

[0017] The thermistor is connected in series with the cathode, and the thermistor is a negative temperature coefficient thermistor.

[0018] Furthermore, the thermistor is in the same layer as the cathode, and the thermistor is disposed adjacent to the cathode.

[0019] In one embodiment, the plurality of light-emitting units include a first light-emitting unit and a second light-emitting unit, wherein the luminous efficiency of the organic light-emitting element in the first light-emitting unit is lower than the luminous efficiency of the organic light-emitting element in the second light-emitting unit;

[0020] When the temperature changes from the first temperature to the second temperature, the change in resistance of the thermistor in the first light-emitting unit is less than the change in resistance of the thermistor in the second light-emitting unit.

[0021] In one embodiment, in a direction perpendicular to the plane of the substrate, the film thickness of the thermistor in the first light-emitting unit is greater than the film thickness of the thermistor in the second light-emitting unit.

[0022] In one embodiment, the resistivity of the thermistor in the first light-emitting unit is less than the resistivity of the thermistor in the second light-emitting unit.

[0023] In one embodiment, the plurality of light-emitting units include a red light-emitting unit for emitting red light, a green light-emitting unit for emitting green light, and a blue light-emitting unit for emitting blue light;

[0024] The first light-emitting unit and the second light-emitting unit are any two of the red light-emitting unit, the green light-emitting unit and the blue light-emitting unit.

[0025] In one embodiment, the thermistor has a film thickness of d in a direction perpendicular to the plane of the substrate, where 0.1 μm ≤ d ≤ 1 μm.

[0026] Based on the same inventive concept, embodiments of this application also provide a display device, including the above-described display panel.

[0027] The display panel and display device provided in this application have the following beneficial effects:

[0028] Based on the inherent characteristics of thermistors, they exhibit different resistance values ​​at different temperatures. In this embodiment of the invention, by providing a thermistor electrically connected to the first electrode in the light-emitting unit, the magnitude of the current flowing to the light-emitting unit can be adjusted using the different resistance values ​​exhibited by the thermistor at different temperatures. For example, when the temperature is low, the carrier mobility of the light-emitting layer decreases due to the low temperature, resulting in a decrease in current. At this time, the change in the resistance value of the thermistor at low temperatures can be used to increase the current flowing to the organic light-emitting element, thereby compensating for the decrease in current caused by the decrease in carrier mobility. Conversely, when the temperature is high, the carrier mobility of the light-emitting layer increases due to the high temperature, resulting in an increase in current. At this time, the change in the resistance value of the thermistor can be used to decrease the current flowing to the light-emitting unit, thereby compensating for the increase in current caused by the increase in carrier mobility.

[0029] On the other hand, since the organic light-emitting element (OLED) is located inside the display panel, its temperature differs significantly from the ambient temperature of the display panel. In other words, the actual temperature affecting the carrier mobility of the light-emitting layer differs markedly from the ambient temperature. Compared to existing technologies that add a temperature sensor to the outside of the display panel and use the ambient temperature detected by the sensor to adjust the current, the thermistor in this embodiment is located inside the display panel. The temperature sensed by the thermistor is close to the temperature of the OLED, which is close to the actual temperature affecting the carrier mobility. Therefore, the current change caused by the thermistor in this embodiment can more accurately compensate for the current change caused by the carrier mobility.

[0030] Furthermore, the embodiments of the present invention can directly feed back the temperature change to the change in the resistance value of the thermistor, and then directly use the change in the resistance value to adjust the current flowing to the organic light-emitting element. Compared with the existing voltage compensation method, the embodiments of the present invention do not require additional adjustment of the driving voltage, the compensation method is simpler and more accurate, and the panel structure is also less complex.

[0031] In summary, the display panel provided by the embodiments of the present invention can accurately compensate the current flowing to the organic light-emitting element, reduce the influence of temperature on the luminous brightness of the organic light-emitting element, that is, reduce the dependence of luminous brightness on temperature, so that the luminous brightness of the organic light-emitting element can approach the standard brightness at both high and low temperatures, effectively improve the color coordinate offset problem of white point, and thus effectively improve the color deviation phenomenon of the image displayed by the display panel. Attached Figure Description

[0032] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0033] Figure 1 This is a schematic diagram of a display panel structure in the prior art;

[0034] Figure 2 This is a schematic diagram of the structure of the display panel provided in an embodiment of the present invention;

[0035] Figure 3 This is a schematic diagram of another structure of the thermistor provided in an embodiment of the present invention;

[0036] Figure 4 This is a schematic diagram of another structure of the thermistor provided in an embodiment of the present invention;

[0037] Figure 5 This is a schematic diagram of another structure of the thermistor provided in an embodiment of the present invention;

[0038] Figure 6 This is a schematic diagram of another structure of the thermistor provided in an embodiment of the present invention;

[0039] Figure 7 This is a schematic diagram of another structure of the thermistor provided in an embodiment of the present invention;

[0040] Figure 8 This is a schematic diagram of the structure of the thermistor in different light-emitting units provided in an embodiment of the present invention;

[0041] Figure 9 This is a schematic diagram of another structure of the thermistor in different light-emitting units provided in the embodiments of the present invention;

[0042] Figure 10 This is a schematic diagram of another structure of the thermistor in different light-emitting units provided in the embodiments of the present invention.

[0043] Figure 11 This is another schematic diagram of the thermistor structure in different light-emitting units provided in the embodiments of the present invention;

[0044] Figure 12 This is a schematic diagram of the structure of the display device provided in the embodiment of this application. Detailed Implementation

[0045] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0046] The terminology used in the embodiments of this invention is for the purpose of describing particular embodiments only and is not intended to limit the invention. The singular forms “a,” “the,” and “the” as used in the embodiments of this invention and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.

[0047] This invention provides a display panel, specifically an organic electroluminescent display panel. Figure 2 This is a schematic diagram of the structure of the display panel provided in an embodiment of the present invention, as shown below. Figure 2As shown, the display panel includes a substrate 1 and a plurality of light-emitting units 2 located on one side of the substrate 1. The light-emitting unit 2 includes an organic light-emitting element 3 and a thermistor 4, wherein the organic light-emitting element 3 includes a first electrode 5, a light-emitting layer 6 and a second electrode 7 stacked in a direction perpendicular to the plane of the substrate 1, and the thermistor 4 is electrically connected to the first electrode 5.

[0048] In addition, please see again Figure 2 The display panel also includes a pixel definition layer 8 located on one side of the substrate 1, the pixel definition layer having a plurality of openings 9 for accommodating the light-emitting layer 6, at least a portion of the anode 10 being exposed within the openings 9.

[0049] Based on the inherent characteristics of the thermistor 4, it exhibits different resistance values ​​at different temperatures. In this embodiment of the invention, by providing the thermistor 4 electrically connected to the first electrode 5 in the light-emitting unit 2, the magnitude of the current flowing to the light-emitting unit 2 can be adjusted using the different resistance values ​​exhibited by the thermistor 4 at different temperatures. For example, when the temperature is low, the carrier mobility of the light-emitting layer 6 decreases due to the low temperature, resulting in a decrease in current. At this time, the change in the resistance value of the thermistor 4 at low temperatures can be used to increase the current flowing to the organic light-emitting element 3, thereby compensating for the decrease in current caused by the decrease in carrier mobility. When the temperature is high, the carrier mobility of the light-emitting layer 6 increases due to the high temperature, resulting in an increase in current. At this time, the change in the resistance value of the thermistor 4 can be used to decrease the current flowing to the light-emitting unit 2, thereby compensating for the increase in current caused by the increase in carrier mobility.

[0050] On the other hand, since the organic light-emitting element 3 is located inside the display panel, its temperature differs significantly from the ambient temperature of the display panel. In other words, the actual temperature affecting the carrier mobility of the light-emitting layer 6 differs significantly from the ambient temperature. Compared to the prior art method of adding a temperature sensor outside the display panel and using the ambient temperature detected by the sensor to adjust the current, the thermistor 4 in this embodiment is located inside the display panel. The temperature sensed by the thermistor 4 is close to the temperature of the organic light-emitting element 3, which is close to the actual temperature affecting the carrier mobility. Therefore, the current change caused by the thermistor 4 in this embodiment can more accurately compensate for the current change caused by the carrier mobility.

[0051] Furthermore, it should be noted that the embodiments of the present invention can directly feed back the temperature change to the resistance change of the thermistor 4, and then directly use the change in resistance to adjust the current flowing to the organic light-emitting element 3. Compared with the existing voltage compensation method, the embodiments of the present invention do not require additional adjustment of the driving voltage, the compensation method is simpler and more accurate, and the complexity of the panel structure is also lower.

[0052] In summary, the display panel provided by this invention can accurately compensate for the current flowing to the organic light-emitting element 3, reducing the impact of temperature on the luminous brightness of the organic light-emitting element 3, that is, reducing the dependence of luminous brightness on temperature. This allows the luminous brightness of the organic light-emitting element 3 to approach the standard brightness under both high and low temperatures, effectively improving the color coordinate shift problem of the white point, and thus effectively improving the color shift phenomenon of the displayed image. Furthermore, the display panel provided by this invention is better suited for application environments with lower temperatures (such as in Northeast China) or higher temperatures (such as near the equator).

[0053] In one implementation, please refer again. Figure 2 The first electrode 5 is the anode 10, and the thermistor 4 is connected in series with the anode 10. The thermistor 4 is a positive temperature coefficient (PTC) thermistor.

[0054] The resistance of the positive temperature coefficient thermistor is positively correlated with temperature; the higher the temperature, the higher the resistance of thermistor 4, and the lower the temperature, the lower the resistance of thermistor 4. At lower temperatures, the resistance of thermistor 4 decreases. Based on the series connection of thermistor 4 and anode 10, the decrease in the resistance of thermistor 4 reduces the equivalent resistance formed by thermistor 4 and anode 10, thereby increasing the current flowing to the organic light-emitting element 3. This increased current compensates for the decrease in current caused by the decrease in carrier mobility. Conversely, at higher temperatures, the resistance of thermistor 4 increases. Again, based on the series connection of thermistor 4 and anode 10, the increase in the resistance of thermistor 4 increases the equivalent resistance formed by thermistor 4 and anode 10, thereby decreasing the current flowing to the light-emitting unit 2. This decreased current compensates for the increase in current caused by the increase in carrier mobility, thus ensuring that the luminous brightness of the organic light-emitting element 3 remains close to the standard brightness at both high and low temperatures.

[0055] In one implementation, please refer again. Figure 2 At least a portion of the thermistor 4 is located on the side of the first electrode 5 facing away from the light-emitting layer 6, and the thermistor 4 is disposed adjacent to the first electrode 5. It should be noted that, in this embodiment of the invention, "adjacent" means that the surface of the thermistor 4 is in contact with the surface of the first electrode 5.

[0056] With this configuration, on the one hand, the thermistor 4 is in direct contact with the first electrode 5, allowing it to more accurately sense temperature changes in the organic light-emitting element 3. This enables more precise control of the current flowing to the organic light-emitting element 3, resulting in greater cancellation between current changes caused by the thermistor 4 and those caused by carrier mobility. On the other hand, the thermistor 4 is located on the side of the first electrode 5 away from the light-emitting layer 6, meaning it is located outside the organic light-emitting element 3. This prevents the thermistor 4 from increasing the microcavity length of the organic light-emitting element 3, thus avoiding any impact on the microcavity effect and ensuring the reliability of the light emission of the organic light-emitting element 3. Furthermore, since the thermistor 4 is located outside the organic light-emitting element 3, it only needs to be formed before or after the fabrication process of the organic light-emitting element 3, and it will not affect the original process flow of the organic light-emitting element 3.

[0057] Furthermore, Figure 3 This is another structural schematic diagram of the thermistor 4 provided in an embodiment of the present invention, as shown below. Figure 3 As shown, the thermistor 4 also covers the sidewall 11 of the first electrode 5, thereby further increasing the contact area between the thermistor 4 and the organic light-emitting element 3, further increasing the accuracy of the thermistor 4 in sensing the temperature change of the organic light-emitting element 3, and realizing more precise control of the current flowing to the organic light-emitting element 3.

[0058] In one implementation, Figure 4 This is another structural schematic diagram of the thermistor 4 provided in an embodiment of the present invention, as shown below. Figure 4 As shown, the first electrode 5 includes a first transparent sub-electrode 12, a reflective sub-electrode 13, and a second transparent sub-electrode 14 stacked in a direction perpendicular to the plane of the substrate 1. The first transparent sub-electrode 12 is located on the side of the reflective sub-electrode 13 facing away from the light-emitting layer 6. The thermistor 4 is located between the first transparent sub-electrode 12 and the reflective sub-electrode 13. Taking the first potential as the anode 10 as an example, the first transparent sub-electrode 12 and the second transparent sub-electrode 14 are indium tin oxide (ITO) electrodes, and the reflective sub-electrode 13 is a silver (Ag) electrode.

[0059] With the above arrangement, the thermistor 4 is closer to the light-emitting layer 6, so the temperature change sensed by the thermistor 4 is closer to the temperature change of the light-emitting layer 6 itself, thus providing more accurate compensation for the changes in current caused by carrier mobility. Moreover, compared to placing the thermistor 4 between the reflective sub-electrode 13 and the second transparent sub-electrode 14, or between the second transparent sub-electrode 14 and the light-emitting layer 6, the thermistor 4 being located between the first transparent sub-electrode 12 and the reflective sub-electrode 13 does not affect the cavity length of the microcavity formed between the second electrode 7 and the reflective sub-electrode 13, and therefore does not affect the optical path of light transmission within the microcavity, avoiding the microcavity effect affecting the organic light-emitting element 3.

[0060] In one implementation, Figure 5 This is another structural schematic diagram of the thermistor 4 provided in an embodiment of the present invention, as shown below. Figure 5 As shown, the first electrode 5 includes a reflective sub-electrode 13 and a light-transmitting sub-electrode 14 stacked in a direction perpendicular to the plane of the substrate 1. The second light-transmitting sub-electrode 14 is located on the side of the reflective sub-electrode 13 facing the light-emitting layer 6. The thermistor 4 is located on the side of the reflective sub-electrode 13 facing away from the second light-transmitting sub-electrode 14, and the thermistor 4 is arranged adjacent to the reflective sub-electrode 13. In this arrangement, the first electrode 5 only includes the reflective sub-electrode 13 and the second light-transmitting sub-electrode 14. The thermistor 4 replaces the first light-transmitting sub-electrode 12 in the first electrode 5, thereby saving the film layer space required by the first light-transmitting sub-electrode 12, which is more conducive to the thinner and lighter design of the display panel.

[0061] In one implementation, Figure 6 This is another structural schematic diagram of the thermistor 4 provided in an embodiment of the present invention, as shown below. Figure 6 As shown, the first electrode 5 is the cathode 15, and the cathodes 15 of the multiple light-emitting units 2 are independent of each other; the thermistor 4 is connected in series with the cathode 15, and the thermistor 4 is a negative temperature coefficient (NTC) thermistor.

[0062] The resistance of the negative temperature coefficient thermistor is negatively correlated with temperature. The higher the temperature, the lower the resistance of thermistor 4; the lower the temperature, the higher the resistance of thermistor 4. At lower temperatures, the resistance of thermistor 4 increases. Based on the series connection of thermistor 4 and cathode 15, the equivalent resistance formed by thermistor 4 and cathode 15 increases. At this time, the voltage of the negative power supply signal written to cathode 15 decreases, and the voltage difference between the anode 10 and cathode 15 of organic light-emitting element 3 increases, thereby increasing the luminous current of light-emitting element 3. Conversely, at higher temperatures, the resistance of thermistor 4 decreases. Based on the series connection of thermistor 4 and cathode 15, the equivalent resistance formed by thermistor 4 and cathode 15 decreases. At this time, the voltage of the negative power supply signal written to cathode 15 increases, and the voltage difference between the anode 10 and cathode 15 of organic light-emitting element 3 decreases, thereby reducing the luminous current of light-emitting element 3. This effectively compensates for the influence of carrier mobility on current at high and low temperatures.

[0063] In one implementation, Figure 7 This is another structural schematic diagram of the thermistor 4 provided in an embodiment of the present invention, as shown below. Figure 7 As shown, the thermistor 4 and the cathode 15 are on the same layer and are arranged adjacent to each other, meaning the sidewall of the thermistor 4 is in contact with the sidewall of the cathode 15. With this arrangement, the thermistor 4 is in direct contact with the organic light-emitting element 3, accurately sensing temperature changes in the organic light-emitting element 3, without obstructing the organic light-emitting element 3. Regardless of whether the thermistor 4 is made of a transparent or opaque material, it will not affect the light emission of the organic light-emitting element 3. This improves both the light emission rate of the organic light-emitting element 3 and the range of materials that can be selected for the thermistor 4.

[0064] It should be noted that when the thermistor 4 is formed of a light-transmitting material, please refer again. Figure 6 The thermistor 4 can also be set on the side of the cathode 15 facing away from the light-emitting layer 6 and adjacent to the cathode 15, so as to avoid affecting the microcavity effect of the organic light-emitting element 3 while improving the accuracy of current regulation.

[0065] Furthermore, it should be noted that the luminous efficiency of organic light-emitting elements 3 varies depending on their color. For organic light-emitting elements 3 with lower luminous efficiency, the carrier mobility of the light-emitting layer 6 is less sensitive to temperature, meaning that the change in carrier mobility is less affected by temperature, and the luminous brightness of the organic light-emitting element 3 deviates less from the standard brightness. Conversely, for organic light-emitting elements 3 with higher luminous efficiency, the carrier mobility of the light-emitting layer 6 is more sensitive to temperature, and correspondingly, the luminous brightness of the organic light-emitting element 3 deviates more from the standard brightness. This difference leads to different degrees of color shift in the brightness of different colors of organic light-emitting elements, resulting in a greater degree of color coordinate shift in the white point.

[0066] Therefore, in this embodiment of the invention, by designing the thermistors 4 in different light-emitting units 2 differently, the thermistors 4 can compensate the current flowing to the organic light-emitting element 3 to different degrees.

[0067] In one implementation, Figure 8 This is a schematic diagram of the thermistor 4 in different light-emitting units 2 provided in the embodiments of the present invention, such as... Figure 8 As shown, the plurality of light-emitting units 2 include a first light-emitting unit 16 and a second light-emitting unit 17. The luminous efficiency of the organic light-emitting element 3 in the first light-emitting unit 16 is lower than that of the organic light-emitting element 3 in the second light-emitting unit 17. When the temperature changes from the first temperature to the second temperature, the change in resistance value of the thermistor 4 in the first light-emitting unit 16 is less than the change in resistance value of the thermistor 4 in the second light-emitting unit 17.

[0068] When the temperature changes from the first temperature to the second temperature, the carrier mobility of the light-emitting layer 6 in the first light-emitting unit 16 is less affected by temperature compared to the second light-emitting unit 17. Therefore, the degree of increase or decrease in current caused by carrier mobility is also smaller. By differentiating the thermistors 4 in the first light-emitting unit 16 and the second light-emitting unit 17, and matching the first light-emitting unit 16 with a thermistor 4 whose resistance value changes less with temperature, the current flowing to the organic light-emitting element 3 in the first light-emitting unit 16 can be compensated to a smaller extent. This better allows the current change caused by the resistance value of the thermistor 4 and the current change caused by carrier mobility to be more completely canceled out. This arrangement can provide differentiated compensation for the current flowing to different organic light-emitting elements 3, thereby more effectively improving the color coordinate shift phenomenon of the white point.

[0069] Furthermore, please see again Figure 8In the direction perpendicular to the plane of the substrate 1, the film thickness of the thermistor 4 in the first light-emitting unit 16 is greater than that in the second light-emitting unit 17. With this configuration, at the same temperature, the resistance value of the thermistor 4 in the first light-emitting unit 16 is lower, and therefore the change in resistance value of the thermistor 4 under the same temperature change is also smaller. By differentiating the film thickness of the photoresistors, a differentiated design of the degree of resistance change of the photoresistors affected by temperature is achieved, thereby better compensating for the different current of the organic light-emitting element 3.

[0070] Alternatively, in another implementation, Figure 9 This is another structural schematic diagram of the thermistor 4 in different light-emitting units 2 provided in the embodiments of the present invention, as shown below. Figure 9 As shown, the resistivity of the thermistor 4 in the first light-emitting unit 16 is less than that in the second light-emitting unit 17, meaning that the thermistors 4 in the first light-emitting unit 16 and the second light-emitting unit 17 are formed using different forming materials (in... Figure 9 In this design, the thermistors 4 in the first light-emitting unit 16 and the second light-emitting unit 17 use different filling materials to represent different forming materials. With this configuration, at the same temperature, the resistance value of the thermistor 4 in the first light-emitting unit 16 is lower, and therefore the change in resistance value of the thermistor 4 under the same temperature change is also smaller. By differentiating the forming materials of the photoresistors, a differentiated design of the degree of resistance change of the photoresistors affected by temperature is achieved, so as to better compensate for the different current of the organic light-emitting element 3.

[0071] It should be noted that when the film thickness of the thermistor 4 in the first light-emitting unit 16 and the second light-emitting unit 17 is different, the two thermistors 4 can be formed using the same material. In this case, the differentiated design of the thermistor 4 is achieved only by utilizing the difference in film thickness. When the forming materials of the thermistor 4 in the first light-emitting unit 16 and the second light-emitting unit 17 are different, please refer again. Figure 9 The film thickness of the two parts of the thermistor 4 can be the same. In this case, the differentiated design of the thermistor 4 can be achieved only by utilizing the difference in the forming materials. Or, Figure 10 This is another structural schematic diagram of the thermistor 4 in different light-emitting units 2 provided in the embodiments of the present invention, as shown below. Figure 10 As shown, the film thickness and forming material of the first light-emitting unit 16 and the second light-emitting unit 17 can be different. At this time, the difference in film thickness and the difference in forming material can be used to realize the differentiated design of the thermistor 4.

[0072] In one implementation, Figure 11 This is another structural schematic diagram of the thermistor 4 in different light-emitting units 2 provided in the embodiments of the present invention, such as... Figure 11As shown, to achieve color display, the display panel typically includes a red organic light-emitting element 21 for emitting red light, a green organic light-emitting element 22 for emitting green light, and a blue organic light-emitting element 23 for emitting blue light. Correspondingly, the multiple light-emitting units 2 include a red light-emitting unit 18 for emitting red light, a green light-emitting unit 19 for emitting green light, and a blue light-emitting unit 20 for emitting blue light. The first light-emitting unit 16 and the second light-emitting unit 17 mentioned above are any two of the red light-emitting unit 18, the blue light-emitting unit 20, and the green light-emitting unit 19. It should be noted that at least two of the red light-emitting unit 18, the blue light-emitting unit 20, and the green light-emitting unit 19 may have different film thicknesses for the thermistors 4, and / or at least two of the light-emitting units may have different forming materials for the thermistors 4.

[0073] Please see again Figure 11 Taking the first light-emitting unit 16 as a blue light-emitting unit 20 and the second light-emitting unit 17 as a red light-emitting unit 18 as an example, since the luminous efficiency of the blue light-emitting material is relatively low and the carrier mobility is less affected by temperature, the film thickness of the thermistor 4 in the blue light-emitting unit 20 can be set to be larger, so that the change in the resistance value of the thermistor 4 in the blue light-emitting unit 20 when the temperature changes is also smaller, which can better offset the current change caused by the carrier mobility.

[0074] Furthermore, it should be noted that in other optional embodiments of the present invention, the film thickness and forming material of the thermistors 4 in the multiple light-emitting units 2 in the display panel may also be the same. In this case, when the temperature changes from the first temperature to the second temperature, the amount of change in the resistance value of the thermistors 4 in different light-emitting units 2 is the same.

[0075] In one implementation, please refer again. Figure 2 In the direction perpendicular to the plane of the substrate 1, the film thickness of the thermistor 4 is d, 0.1μm≤d≤1μm.

[0076] If the film thickness of thermistor 4 is too small, its resistance will be too large. Even a slight temperature change will cause a significant change in resistance, leading to overcompensation of the current. Conversely, if the film thickness is too large, its resistance will be too small, resulting in insufficient current compensation even with significant temperature changes. Therefore, setting d between 0.1 μm and 1 μm ensures that the resistance of thermistor 4 changes appropriately with temperature variations, accurately compensating for current changes caused by carrier mobility and avoiding both overcompensation and undercompensation.

[0077] Based on the same inventive concept, this application also provides a display device. Figure 12 This is a schematic diagram of the structure of the display device provided in the embodiments of this application, such as... Figure 12 As shown, the display device includes the aforementioned display panel 100. Of course, Figure 10 The electronic device shown is for illustrative purposes only. It can be any display device with display function, such as a mobile phone, tablet computer, laptop computer, e-reader or television.

[0078] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

[0079] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A display panel, characterized in that, include: Substrate; Multiple light-emitting units are located on one side of the substrate. Each light-emitting unit includes an organic light-emitting element and a thermistor. The organic light-emitting element includes a first electrode, a light-emitting layer, and a second electrode stacked in a direction perpendicular to the plane of the substrate. The thermistor is electrically connected to the first electrode. The plurality of light-emitting units include a first light-emitting unit and a second light-emitting unit. The luminous efficiency of the organic light-emitting element in the first light-emitting unit is lower than that of the organic light-emitting element in the second light-emitting unit. When the temperature changes from the first temperature to the second temperature, the change in resistance value of the thermistor in the first light-emitting unit is less than the change in resistance value of the thermistor in the second light-emitting unit.

2. The display panel according to claim 1, characterized in that, The first electrode is the anode; The thermistor is connected in series with the anode, and the thermistor is a positive temperature coefficient thermistor.

3. The display panel according to claim 1, characterized in that, At least a portion of the thermistor is located on the side of the first electrode opposite to the light-emitting layer, and the thermistor is disposed adjacent to the first electrode.

4. The display panel according to claim 3, characterized in that, The thermistor also covers the sidewall of the first electrode.

5. The display panel according to claim 1, characterized in that, The first electrode includes a first light-transmitting sub-electrode, a reflective sub-electrode, and a second light-transmitting sub-electrode stacked in a direction perpendicular to the plane of the substrate, wherein the first light-transmitting sub-electrode is located on the side of the reflective sub-electrode facing away from the light-emitting layer; The thermistor is located between the first transparent sub-electrode and the reflective sub-electrode.

6. The display panel according to claim 1, characterized in that, The first electrode includes a reflective sub-electrode and a light-transmitting sub-electrode stacked in a direction perpendicular to the plane of the substrate, wherein the second light-transmitting sub-electrode is located on the side of the reflective sub-electrode facing the light-emitting layer; The thermistor is located on the side of the reflective sub-electrode that faces away from the second light-transmitting sub-electrode, and the thermistor is disposed adjacent to the reflective sub-electrode.

7. The display panel according to claim 1, characterized in that, The first electrode is a cathode, and the cathodes of the plurality of light-emitting units are independent of each other; The thermistor is connected in series with the cathode, and the thermistor is a negative temperature coefficient thermistor.

8. The display panel according to claim 7, characterized in that, The thermistor is in the same layer as the cathode, and the thermistor is disposed adjacent to the cathode.

9. The display panel according to claim 1, characterized in that, In a direction perpendicular to the plane of the substrate, the film thickness of the thermistor in the first light-emitting unit is greater than the film thickness of the thermistor in the second light-emitting unit.

10. The display panel according to claim 1, characterized in that, The resistivity of the thermistor in the first light-emitting unit is less than the resistivity of the thermistor in the second light-emitting unit.

11. The display panel according to claim 1, characterized in that, The plurality of light-emitting units include a red light-emitting unit for emitting red light, a green light-emitting unit for emitting green light, and a blue light-emitting unit for emitting blue light; The first light-emitting unit and the second light-emitting unit are any two of the red light-emitting unit, the green light-emitting unit and the blue light-emitting unit.

12. The display panel according to claim 1, characterized in that, In a direction perpendicular to the plane of the substrate, the film thickness of the thermistor is d, where 0.1μm≤d≤1μm.

13. A display device, characterized in that, Includes the display panel as described in any one of claims 1 to 12.

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