Display panel and display device
By adjusting the voltage or turn-on voltage between the charge generation layer and the electrode of different types of light emitting devices in the display panel, the lateral leakage problem is solved, the color purity and luminous efficiency are improved, and the power consumption is reduced.
Patent Information
- Application Number
- CN202510741483.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-04
- Publication Date
- 2025-08-29
Smart Images
Figure CN120569049A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of display technology, and in particular to a display panel and a display device. Background Art
[0002] A display panel is a device used to display images and text.
[0003] Currently, some display panels adopt a tandem design. Specifically, multiple light-emitting units are connected in series through a charge generation layer (CGL), which can achieve higher brightness, longer life and lower power consumption.
[0004] However, the charge generation layer in the above display panel has a high conductivity and is prone to lateral leakage problems, resulting in poor display effects. Summary of the Invention
[0005] The present invention provides a display panel and a display device. The technical solution is as follows:
[0006] According to one aspect of the present application, a display panel is provided, comprising: a driving backplane and a plurality of light-emitting devices;
[0007] The light-emitting device includes: a first electrode, a first light-emitting unit, a charge generation layer, a second light-emitting unit, and a second electrode; the first electrode is located on one side of the driving backplane and is electrically connected to the driving backplane; the second electrode is located on a side of the first electrode away from the driving backplane; the first light-emitting unit, the charge generation layer, and the second light-emitting unit are stacked between the first electrode and the second electrode, with the first light-emitting unit being closer to the driving backplane than the second light-emitting unit; the first light-emitting unit and the second light-emitting unit in the same light-emitting device emit the same light color;
[0008] Among them, for a first light-emitting device and a second light-emitting device that are adjacently distributed and of different types among the multiple light-emitting devices, during the light-emitting process of the first light-emitting device, the voltage between the charge generation layer and the second electrode in the second light-emitting device is less than the turn-on voltage of the second light-emitting unit in the second light-emitting device.
[0009] Optionally, a turn-on voltage of the first light-emitting device is greater than a turn-on voltage of the second light-emitting device;
[0010] The turn-on voltage of the second light-emitting unit in the first light-emitting device is lower than the turn-on voltage of the first light-emitting unit, and / or the turn-on voltage of the second light-emitting unit in the second light-emitting device is higher than the turn-on voltage of the first light-emitting unit.
[0011] Optionally, in the first light-emitting device, a thickness of the second light-emitting layer in the second light-emitting unit is smaller than a thickness of the first light-emitting layer in the first light-emitting unit.
[0012] Optionally, in the first light-emitting device, a thickness of the second electron blocking layer in the second light-emitting unit is greater than a thickness of the first electron blocking layer in the first light-emitting unit;
[0013] The first electron blocking layer is located on a side of the first light-emitting layer away from the charge generation layer, and the second electron blocking layer is located on a side of the second light-emitting layer close to the charge generation layer.
[0014] Optionally, the first light-emitting unit in the second light-emitting device includes: a first light-emitting layer and an organic functional layer, wherein the organic functional layer is located on a side of the first light-emitting layer away from the charge generation layer, and the organic functional layer is in direct contact with the first light-emitting layer;
[0015] The second light-emitting unit in the second light-emitting device includes: a second light-emitting layer and a second electron blocking layer, wherein the second electron blocking layer is located on a side of the second light-emitting layer facing the charge generation layer, and the second electron blocking layer is in direct contact with the second light-emitting layer;
[0016] Wherein, the thickness of the second electron blocking layer is greater than the thickness of the organic functional layer.
[0017] Optionally, the organic functional layer is an auxiliary hole transport layer;
[0018] In the second light-emitting device, the side of the first light-emitting layer in the first light-emitting unit facing the charge generation layer is in direct contact with the first electron transport layer; in the first light-emitting device, the side of the first light-emitting layer in the first light-emitting unit facing away from the charge generation layer is in direct contact with the first electron blocking layer, and the side of the first light-emitting layer in the first light-emitting unit facing the charge generation layer is in direct contact with the first hole blocking layer.
[0019] Optionally, the first light-emitting unit in the second light-emitting device further includes: a first hole transport layer located on a side of the auxiliary hole transport layer away from the first light-emitting layer;
[0020] The first light-emitting unit in the first light-emitting device further includes: a first hole transport layer located on a side of the first electron blocking layer away from the first light-emitting layer;
[0021] The first hole transport layer in the second light-emitting device and the first hole transport layer in the first light-emitting device are of the same layer structure.
[0022] Optionally, the thickness of the second electron blocking layer in the second light-emitting device is equal to the sum of the thickness of the auxiliary hole transport layer in the second light-emitting device and the thickness of the first hole blocking layer in the first light-emitting device.
[0023] Optionally, the organic functional layer is a first electron blocking layer;
[0024] In the second light-emitting device, the side of the first light-emitting layer in the first light-emitting unit facing the charge generation layer is in direct contact with the first electron transport layer; in the first light-emitting device, the side of the first light-emitting layer in the first light-emitting unit facing away from the charge generation layer is in direct contact with the first electron blocking layer, and the side of the first light-emitting layer in the first light-emitting unit facing the charge generation layer is in direct contact with the first hole blocking layer.
[0025] Optionally, the thickness of the second electron blocking layer in the second light-emitting device is equal to the sum of the thickness of the first electron blocking layer in the second light-emitting device and the thickness of the first hole blocking layer in the first light-emitting device.
[0026] Optionally, the energy level difference between the highest occupied molecular orbital of the second electron blocking layer in the second light-emitting device and the second light-emitting layer in the second light-emitting device is greater than or equal to 0.2 volts.
[0027] Optionally, in the second light-emitting device, materials of the first light-emitting layer in the first light-emitting unit and the second light-emitting layer in the second light-emitting unit both include: a P-type host material and an N-type host material;
[0028] In the second light-emitting device, the ratio of the content of the P-type host material to the content of the N-type host material in the second light-emitting layer is greater than the ratio of the content of the P-type host material to the content of the N-type host material in the first light-emitting layer.
[0029] Optionally, an absolute value of a difference between a turn-on voltage of the second light-emitting unit in the first light-emitting device and a turn-on voltage of the second light-emitting unit in the second light-emitting device is less than or equal to 0.5V.
[0030] Optionally, the light emitting color of the first light emitting device is blue, and the light emitting color of the second light emitting device is red or green.
[0031] Optionally, during the light emission process of the first light emitting device, the voltage between the charge generation layer and the second electrode in the second light emitting device is less than 2.0V.
[0032] On the other hand, a display device is provided, including: a power supply component, and a display panel electrically connected to the power supply component, wherein the display panel includes: any one of the above-mentioned display panels.
[0033] The beneficial effects of the technical solutions provided in the embodiments of the present application include at least:
[0034] For a first light-emitting device and a second light-emitting device of different types, by adjusting the voltage between the charge generation layer and the second electrode in the second light-emitting device, or adjusting the turn-on voltage of the second light-emitting unit in the second light-emitting device, it is possible to make the voltage between the charge generation layer and the second electrode in the second light-emitting device less than the turn-on voltage of the second light-emitting unit in the second light-emitting device during the light-emitting process of the first light-emitting device, thereby ensuring that the leakage current is not sufficient to light up the second light-emitting unit in the second light-emitting device, thereby avoiding the problem of lateral crosstalk and further improving the color purity of the display panel. BRIEF DESCRIPTION OF THE DRAWINGS
[0035] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.
[0036] Figure 1 This is a structural diagram of a display panel provided by the related art;
[0037] Figure 2 This is a structural diagram of another display panel provided by the related art;
[0038] Figure 3 is a structural diagram of a display panel provided in an embodiment of the present application;
[0039] Figure 4 is a structural diagram of another display panel provided in an embodiment of the present application;
[0040] Figure 5 is a structural diagram of another display panel provided in an embodiment of the present application;
[0041] Figure 6 is a structural diagram of another display panel provided in an embodiment of the present application;
[0042] Figure 7 is a structural diagram of another display panel provided in an embodiment of the present application;
[0043] Figure 8 This is a schematic structural diagram of another display panel provided in an embodiment of the present application.
[0044] The above drawings illustrate specific embodiments of the present application, which will be described in more detail below. These drawings and the textual description are not intended to limit the scope of the present application in any way, but rather to illustrate the concepts of the present application to those skilled in the art by reference to specific embodiments. DETAILED DESCRIPTION
[0045] In order to make the objectives, technical solutions and advantages of this application clearer, the implementation methods of this application will be further described in detail below with reference to the accompanying drawings.
[0046] A display panel with serial design can be found in Figure 1 , Figure 1 This is a schematic diagram of the structure of a display panel provided by related technology. Display panel A comprises a driving backplane A1, a pixel definition layer A3, and multiple light-emitting devices A2. Light-emitting devices A2 include a first electrode A21, a first light-emitting unit A22, a charge generation layer A23, a second light-emitting unit A24, and a second electrode A25. The charge generation layer A4 connects the first light-emitting unit A23 and the second light-emitting unit A25 in series, achieving higher brightness, longer life, and lower power consumption.
[0047] In high-resolution display panels, adjacent light-emitting devices A2 are closely spaced. Due to the high conductivity of the material used in the charge generation layer A4 of light-emitting device A2, a series design is prone to lateral leakage. For example, if multiple light-emitting devices A2 include a red light-emitting device R, a green light-emitting device G, and a blue light-emitting device B, during the emission of blue light-emitting device B, current can leak through the charge generation layer A4 to adjacent light-emitting devices. Because the turn-on voltages of the red and green light-emitting devices R and G are typically lower than that of the blue light-emitting device B—for example, if the turn-on voltage of a single light-emitting unit in the red and green light-emitting devices R and G is 2.0V, and the turn-on voltage of a single light-emitting unit in the blue light-emitting device B is 2.5V—the red and green light-emitting devices R and G are prone to ignition due to leakage, resulting in a loss of luminous efficiency and reduced color purity.
[0048] Please refer to Figure 2 , Figure 2This is a schematic diagram of the structure of another display panel provided by related art. Display panel A also includes a light extraction layer A5. A first light-emitting unit A22 includes a p-type hole transport layer p-HTL, a first hole transport layer HTL1, a first electron blocking layer EBL1, a first light-emitting layer EML1, a first hole blocking layer HBL1, and a first electron transport layer ETL1. A second light-emitting unit A24 includes a second hole transport layer HTL2, a second electron blocking layer EBL2, a second light-emitting layer EML2, a second hole blocking layer HBL2, a second electron transport layer ETL2, and an electron injection layer EIL. The multiple film layers in the first light-emitting unit A22 and the second light-emitting unit A24 are all common layers, that is, film layers shared by multiple light-emitting devices A2, which further increases the possibility of lateral leakage.
[0049] In some related technologies, trenches or retaining walls are provided above the pixel definition layer A3 in the display panel to block the common layer prone to lateral leakage, thereby reducing the degree of lateral current crosstalk. However, the trenches or retaining walls also isolate the second electrode A25 of the light-emitting device A2, resulting in increased impedance, increased power consumption, and poor uniformity, thus resulting in yield loss and increased costs.
[0050] The present application provides a display panel. Figure 3 , Figure 3 1 is a schematic structural diagram of a display panel provided in an embodiment of the present application. The display panel 00 includes: a driving backplane 10 and a plurality of light-emitting devices 20 .
[0051] The display panel provided in the embodiment of the present application can be an organic light emitting diode (OLED) display panel. The OLED display panel has the characteristics of self-luminescence, wide viewing angle, wide color gamut, lightness, and flexibility, and can be applied to various display fields.
[0052] The driving backplane 10 can be used to support other structures in the display panel 00, such as multiple light-emitting devices 20. The driving backplane 10 can also include a substrate and a driving circuit provided on the substrate, so that the driving backplane 10 can be used to drive the light-emitting devices 20 to emit light.
[0053] Multiple light-emitting devices 20 are located on the same side of the driver backplane 10, and the light-emitting devices 20 are used to emit light beams in a direction away from the driver backplane 10. The multiple light-emitting devices 20 can be electrically connected to the driver backplane 10, so that the driver backplane 10 can control the light-emitting state and light brightness of each light-emitting device 20.
[0054] In some possible implementations, such as Figure 3As shown, the display panel 00 may further include: a pixel definition layer 30, the pixel definition layer 30 having a plurality of openings, a plurality of light-emitting devices 20 may correspond to the plurality of openings, and at least part of the light-emitting devices 20 are located in the corresponding openings, so that the pixel definition layer 30 can be used to divide the plurality of light-emitting devices 20.
[0055] The light-emitting device 20 includes a first electrode 21, a first light-emitting unit 22, a charge generation layer 23, a second light-emitting unit 24, and a second electrode 25. The first electrode 21 is located on one side of the driving backplane 10 and is electrically connected to the driving backplane 10. The second electrode 25 is located on the side of the first electrode 21 facing away from the driving backplane 10. The first electrode 21 can be an anode, and the second electrode 25 can be a cathode. The driving circuit in the driving backplane 10 is electrically connected to the first electrode 21 and the second electrode 25. Under the control of the driving backplane 10, the first electrode 21 can generate holes, and the second electrode 25 can generate electrons.
[0056] It should be noted that the charge generation layer 23 in the first light emitting device 20a and the charge generation layer 23 in the second light emitting device 20b are connected. In some possible implementations, the first electrodes 21 in the plurality of light emitting devices 20 can be separately provided, and the second electrodes 25 in the plurality of light emitting devices 20 can be continuously provided. For example, Figure 3 As shown, the first electrode 21 in each light-emitting device 20 can be an electrode block distributed within the corresponding pixel opening. The second electrode 25 in multiple light-emitting devices 20 is a continuous, integrated structure. Therefore, for the first light-emitting unit 22 and the second light-emitting unit 24, since the charge generation layer 23 and the second electrode 25 on both sides of the second light-emitting unit 24 are continuous layers, the second light-emitting unit 24 is more susceptible to lateral leakage current.
[0057] The first light-emitting unit 22, the charge generation layer 23, and the second light-emitting unit 24 are stacked between the first electrode 21 and the second electrode 25, and the first light-emitting unit 22 is closer to the driving backplane 10 than the second light-emitting unit 24. The first light-emitting unit 22 and the second light-emitting unit 24 in the same light-emitting device 20 have the same light-emitting color. Here, the charge generation layer 23 can connect the first light-emitting unit 22 and the second light-emitting unit 24 in the same light-emitting device 20 in series, and can generate hole-electron pairs under the action of the electric field so as to be injected into the light-emitting layer to realize light emission. Therefore, under the drive of the driving backplane 10, the first light-emitting unit 22 and the second light-emitting unit 24 in the same light-emitting device 20 can emit light at the same time, thereby improving the light-emitting efficiency of the light-emitting device 20.
[0058] For a first light-emitting device 20a and a second light-emitting device 20b of different types that are adjacently distributed among the plurality of light-emitting devices 20, during the light-emitting process of the first light-emitting device 20a, the voltage between the charge generation layer 23 and the second electrode 25 in the second light-emitting device 20b is less than the turn-on voltage of the second light-emitting unit 24 in the second light-emitting device 20b. Here, the first light-emitting device 20a and the second light-emitting device 20b may emit different colors. Due to the different properties of the materials used for light emission in the different types of light-emitting devices 20, the turn-on voltages of the first light-emitting device 20a and the second light-emitting device 20b are different. The turn-on voltage refers to the minimum voltage required for the light-emitting device 20 to begin emitting light.
[0059] For example, during the light emission process of the first light-emitting device 20a, leakage current is easily transmitted through the charge generation layer 23 to the adjacent second light-emitting device 20b, and a potential difference will exist between the charge generation layer 23 and the second electrode 25 in the second light-emitting device 20b. In the case where the turn-on voltage of the first light-emitting device 20a is greater than the turn-on voltage of the second light-emitting device 20b, the embodiment of the present application can adjust the voltage between the charge generation layer 23 and the second electrode 25 in the second light-emitting device 20b to be lower; or, adjust the turn-on voltage of the second light-emitting unit in the second light-emitting device to be higher. In this way, it can ensure that the potential difference between the charge generation layer 23 and the second electrode 25 in the second light-emitting device 20b is lower than the turn-on voltage, that is, the leakage current is insufficient to illuminate the second light-emitting unit 24 in the second light-emitting device 20b, thereby avoiding the problem of lateral crosstalk and improving color purity.
[0060] In the case where the turn-on voltage of the first light-emitting device 20a is lower than the turn-on voltage of the second light-emitting device 20b, since the turn-on voltage of the second light-emitting device 20b is higher, even if the leakage current is transmitted to the adjacent second light-emitting device 20b through the charge generation layer 23, the leakage current is not sufficient to light up the second light-emitting unit 24 in the second light-emitting device 20b, thereby avoiding the lateral crosstalk problem and further improving the color purity.
[0061] It should be noted that, because the embodiment of the present application can avoid lateral crosstalk by adjusting the voltage between the charge generation layer 23 in the second light-emitting device 20b and the second electrode 25, the charge generation layer 23 in the first light-emitting device 20a and the charge generation layer 23 in the second light-emitting device 20b can be connected. In other words, the side of the pixel definition layer 30 facing away from the driver backplane 10 does not need to be provided with a groove or retaining wall, thereby improving the continuity of the second electrode 25, reducing impedance and power consumption, and thus improving the yield of the display panel 00.
[0062] In summary, the embodiments of the present application provide a display panel, wherein, for a first light-emitting device and a second light-emitting device of different types, by adjusting the voltage between the charge generation layer and the second electrode in the second light-emitting device, or adjusting the turn-on voltage of the second light-emitting unit in the second light-emitting device, it is possible to make the voltage between the charge generation layer and the second electrode in the second light-emitting device less than the turn-on voltage of the second light-emitting unit in the second light-emitting device during the light-emitting process of the first light-emitting device, thereby ensuring that the leakage current is insufficient to light up the second light-emitting unit in the second light-emitting device, thereby avoiding the problem of lateral crosstalk and further improving the color purity of the display panel.
[0063] In some possible implementations, the turn-on voltage of the first light-emitting device 20a is greater than the turn-on voltage of the second light-emitting device 20b. Here, since the first light-emitting unit 22 and the second light-emitting unit 24 in the light-emitting device 20 are arranged in series via the charge generation layer 23, the turn-on voltage of the light-emitting device 20 is the sum of the turn-on voltages of the first light-emitting unit 22 and the turn-on voltages of the second light-emitting unit 24 in the light-emitting device 20.
[0064] The turn-on voltage of the second light-emitting unit 24 in the first light-emitting device 20a is lower than the turn-on voltage of the first light-emitting unit 22, and / or the turn-on voltage of the second light-emitting unit 24 in the second light-emitting device 20b is higher than the turn-on voltage of the first light-emitting unit 22. This includes the following three implementations:
[0065] In a first possible implementation, the turn-on voltage of the second light-emitting unit 24 in the first light-emitting device 20a is lower than the turn-on voltage of the first light-emitting unit 22. That is, the embodiment of the present application can reduce the turn-on voltage of the second light-emitting unit 24 in the first light-emitting device 20a, thereby reducing the leakage current. This can reduce the potential difference between the charge generation layer 23 and the second electrode 25 in the second light-emitting device 20b, thereby ensuring that the leakage current is insufficient to illuminate the second light-emitting unit 22 in the second light-emitting device 20b.
[0066] It should be noted that, in the related art, the turn-on voltages of the multiple light-emitting units in the same light-emitting device 20 are the same, such as Figure 1 and Figure 2 As shown, the first light-emitting unit A22 and the second light-emitting unit A24 in the same light-emitting device 20 have the same turn-on voltage. However, in the embodiment of the present application, the turn-on voltage of at least some of the light-emitting units in the same light-emitting device 20 can be adjusted so that leakage current cannot illuminate other light-emitting devices 20 that do not need to work.
[0067] In a second possible implementation, the turn-on voltage of the second light-emitting unit 24 in the second light-emitting device 20b is greater than the turn-on voltage of the first light-emitting unit 22. In other words, the embodiment of the present application can increase the turn-on voltage of the second light-emitting unit 24 in the second light-emitting device 20b, making it more difficult for the second light-emitting unit 24 in the second light-emitting device 20b to be illuminated, thereby preventing the leakage current generated during the light-emitting process of the first light-emitting device 20a from being sufficient to illuminate the second light-emitting unit 22 in the second light-emitting device 20b.
[0068] In a third possible implementation, the turn-on voltage of the second light-emitting unit 24 in the first light-emitting device 20a is lower than the turn-on voltage of the first light-emitting unit 22, and the turn-on voltage of the second light-emitting unit 24 in the second light-emitting device 20b is higher than the turn-on voltage of the first light-emitting unit 22. In other words, the embodiment of the present application can reduce the turn-on voltage of the second light-emitting unit 24 in the first light-emitting device 20a while increasing the turn-on voltage of the second light-emitting unit 24 in the second light-emitting device 20b. This can further reduce the risk of lateral crosstalk through the combined effect of the two.
[0069] In the embodiment of the present application, based on the above three implementations, the turn-on voltage of the second light-emitting unit 24 in the first light-emitting device 20a can be reduced, and / or the turn-on voltage of the second light-emitting unit 24 in the second light-emitting device 20b can be increased. Since the turn-on voltage of the first light-emitting device 20a is greater than the turn-on voltage of the second light-emitting device 20b, the difference between the turn-on voltage of the second light-emitting unit 24 in the first light-emitting device 20a and the turn-on voltage of the second light-emitting unit 24 in the second light-emitting device 20b can be minimized.
[0070] Optionally, the absolute value of the difference between the turn-on voltage of the second light-emitting unit 24 in the first light-emitting device 20a and the turn-on voltage of the second light-emitting unit 24 in the second light-emitting device 20b is less than or equal to 0.5 V. In some exemplary embodiments, the absolute value of the difference between the turn-on voltages of the second light-emitting units 24 in different light-emitting devices 20 is less than or equal to 0.3 V, thereby further reducing the difference in turn-on voltages and lowering the risk of lateral crosstalk.
[0071] Optionally, the light emitting color of the first light emitting device 20a is blue, and the light emitting color of the second light emitting device 20b is red or green. Figure 3As shown, the second light-emitting devices 20b on either side of the first light-emitting device 20a can emit red and green light, respectively. Thus, for the red second light-emitting device 20b, during the first light-emitting device 20a's light emission process, the voltage between the charge generation layer 23 and the second electrode 25 in the second light-emitting device 20b is lower than the turn-on voltage of the second light-emitting unit 24 in the red second light-emitting device 20b. For the green second light-emitting device 20b, during the first light-emitting device 20a's light emission process, the voltage between the charge generation layer 23 and the second electrode 25 in the second light-emitting device 20b is lower than the turn-on voltage of the second light-emitting unit 24 in the green second light-emitting device 20b.
[0072] Optionally, during the light emission process of the first light-emitting device 20a, the voltage between the charge generation layer 23 and the second electrode 25 in the second light-emitting device 20b is less than 2.0 V. Here, since the turn-on voltage of a single light-emitting unit in the red light-emitting device and the green light-emitting device in the related art is 2.0 V, and the turn-on voltage of a single light-emitting unit in the blue light-emitting device is 2.5 V, such a setting can ensure that the potential difference caused by lateral leakage is low and is insufficient to light up the red light-emitting device or the green light-emitting device with a lower turn-on voltage.
[0073] For example, the turn-on voltages of different types of light emitting devices 20 may satisfy:
[0074] ∣Von_Blue-Von_Green∣≤0.3V;
[0075] ∣Von_Blue-Von_Red∣≤0.3V;
[0076] Here, Von_Blue is the turn-on voltage of the second light-emitting unit 24 in the first light-emitting device 20a emitting blue light, Von_Green is the turn-on voltage of the second light-emitting unit 24 in the second light-emitting device 20b emitting green light, and Von_Red is the turn-on voltage of the second light-emitting unit 24 in the second light-emitting device 20b emitting red light. By limiting the difference in the turn-on voltages of the second light-emitting units 24 in different types of light-emitting devices 20 to be relatively small, the turn-on voltage of the second light-emitting unit 24 in the first light-emitting device 20a can be reduced, or the turn-on voltage of the second light-emitting unit 24 in the second light-emitting device 20b can be increased, thereby reducing the risk of lateral crosstalk.
[0077] In an exemplary embodiment, please refer to Figure 4 , Figure 4This is a schematic diagram of the structure of another display panel provided by an embodiment of the present application. The display panel 00 may further include a light extraction layer 40 , located on the side of the second electrode 25 facing away from the driving backplane 10 . The light extraction layer 40 can reduce light loss caused by total internal reflection in the light-emitting device 20 , thereby improving the light extraction efficiency of the light-emitting device 20 .
[0078] The first light-emitting unit 22 may further include: a p-type hole transport layer p-HTL, a first hole transport layer HTL1, a first electron blocking layer EBL1, a first light-emitting layer EML1, a first hole blocking layer HBL1, and a first electron transport layer ETL1, which are stacked in a direction away from the first electrode 21. The second light-emitting unit 24 may further include: a second hole transport layer HTL2, a second electron blocking layer EBL2, a second light-emitting layer EML2, a second hole blocking layer HBL2, a second electron transport layer ETL2, and an electron injection layer EIL, which are stacked in a direction away from the charge generation layer 23.
[0079] The p-type hole transport layer p-HTL can transfer holes from the first electrode 21 to the first hole transport layer HTL1, and the first hole transport layer HTL1 can transfer holes from the p-type hole transport layer p-HTL to the first light-emitting layer EML1. In the first light-emitting unit 22, the provision of the p-type hole transport layer p-HTL can reduce the barrier to hole injection and improve the hole injection efficiency. The second hole transport layer HTL2 can transfer holes from the charge generation layer 23 to the second light-emitting layer EML2.
[0080] The first electron transport layer ETL1 can transfer electrons from the charge generation layer 23 to the first light-emitting layer EML1. The electron injection layer EIL can inject electrons from the second electrode 25 into the second electron transport layer ETL2, and the second electron transport layer ETL2 can transfer electrons from the electron injection layer EIL to the second light-emitting layer EML2. In the second light-emitting unit 24, the provision of the electron injection layer EIL can lower the barrier for electron injection and improve the electron injection efficiency.
[0081] The first electron blocking layer EBL1 can block electrons from the charge generation layer 23 at the first light-emitting layer EML1 and transfer holes from the first hole transport layer HTL1 to the first light-emitting layer EML1. The second electron blocking layer EBL2 can block electrons from the second electrode 25 at the second light-emitting layer EML2 and transfer holes from the second hole transport layer HTL2 to the second light-emitting layer EML2. This can increase the concentration of electrons at the first light-emitting layer EML1 and the second light-emitting layer EML2, thereby increasing the probability of electron-hole combination and improving the luminous efficiency of the light-emitting device 20.
[0082] The first hole blocking layer HBL1 can block holes from the first electrode 21 at the first light-emitting layer EML1 and transfer electrons from the first electron transport layer ETL1 to the first light-emitting layer EML1. The second hole blocking layer HBL2 can block holes from the charge generation layer 23 at the second light-emitting layer EML2 and transfer electrons from the second electron transport layer ETL2 to the second light-emitting layer EML2. This can increase the concentration of holes in the first light-emitting layer EML1 and the second light-emitting layer EML2, thereby increasing the probability of electron-hole combination and improving the luminous efficiency of the light-emitting device 20.
[0083] Under the action of an electric field, when holes and electrons are transferred to the first light-emitting layer EML1 or the second light-emitting layer EML2, they combine to produce excitons, which can excite the first light-emitting layer EML1 or the second light-emitting layer EML2 to produce photons, thereby achieving light emission. In the embodiment of the present application, the first light-emitting layer EML1 and the second light-emitting layer EML2 in the same light-emitting device 20 emit the same color.
[0084] It should be noted that Figure 4 The gap between the first light-emitting layer EML1 and the first hole blocking layer HBL1 is to clearly indicate the difference in thickness of some film layers in the first light-emitting device 20a and the second light-emitting device 20b. In actual products, the first light-emitting layer EML1 and the first hole blocking layer HBL1 are in contact with each other, rather than suspended in the air, which means that the gap does not exist. In addition, in the direction parallel to the driving backplane 10, adjacent light-emitting devices 20 can be set Figure 3 The pixel definition layer 30 shown, that is, the gap between adjacent light-emitting devices 20 in an actual product, may not exist.
[0085] The following describes how to adjust the turn-on voltage of the first light emitting device 20a:
[0086] For some possible implementations, see Figure 4In the first light-emitting device 20a, the thickness of the second light-emitting layer EML2 in the second light-emitting unit 24 is less than the thickness of the first light-emitting layer EML1 in the first light-emitting unit 22. In other words, the embodiment of the present application can reduce the thickness of the second light-emitting layer EML2 in the first light-emitting device 20a. Since the smaller the thickness of the second light-emitting layer EML2 in the first light-emitting device 20a, the lower the resistance of the second light-emitting layer EML2 in the first light-emitting device 20a, the turn-on voltage of the second light-emitting unit 24 in the first light-emitting device 20a can be lower than the turn-on voltage of the first light-emitting unit 22. This not only reduces leakage current, ensuring that the leakage current is insufficient to illuminate the second light-emitting unit 22 in the second light-emitting device 20b, but also reduces the power consumption of the second light-emitting device 20b. For example, in the first light-emitting device 20a, the first light-emitting layer EML1 and the second light-emitting layer EML2 can both emit blue light.
[0087] Optionally, in the first light emitting device 20a, the thickness of the second light emitting layer EML2 and the thickness of the first light emitting layer EML1 may satisfy:
[0088] 5 nm ≤ d1-d2 ≤ 10 nm;
[0089] Where d1 is the thickness of the first light-emitting layer EML1, and d2 is the thickness of the second light-emitting layer EML2. By limiting the difference between the thickness of the second light-emitting layer EML2 and the thickness of the first light-emitting layer EML1 in the first light-emitting device 20a to be greater than or equal to 5 nanometers, the turn-on voltage of the second light-emitting unit 24 in the first light-emitting device 20a can be reduced. Furthermore, by limiting the difference between the thickness of the second light-emitting layer EML2 and the thickness of the first light-emitting layer EML1 in the first light-emitting device 20a to be less than or equal to 10 nanometers, the thickness of the second light-emitting layer EML2 in the first light-emitting device 20a will not be too thin, thereby ensuring that the second light-emitting layer EML2 can be manufactured.
[0090] In the embodiment of the present application, the first electrode 21 can be a fully reflective electrode, and the second electrode 25 can be a semi-transmissive semi-reflective electrode. In this way, a microcavity can be formed between the first electrode 21 and the second electrode 25. In the microcavity, light with a wavelength range corresponding to the cavity length of the microcavity can resonate, and the light can be strengthened due to constructive interference.
[0091] Because the wavelength ranges of light emitted by light-emitting devices 20 of different luminous colors are different, the embodiment of the present application can adjust the cavity length of the microcavity by adjusting the thickness of the film layer in the first light-emitting unit 22 and the second light-emitting unit 24, so that the cavity length of the microcavity is adapted to the wavelength range of the light emitted by the light-emitting device 20, ensuring that the light can be strengthened due to constructive interference. For example, the display panel 00 can meet at least one of the following conditions:
[0092] 1) The thickness of the first electron blocking layer EBL1 in the first light emitting device 20 a is different from the thickness of the first electron blocking layer EBL1 in the second light emitting device 20 b .
[0093] 2) The thickness of the first light emitting layer EML1 in the first light emitting device 20a is different from the thickness of the first light emitting layer EML1 in the second light emitting device 20b.
[0094] 3) The thickness of the second electron blocking layer EBL2 in the first light emitting device 20a is different from the thickness of the second electron blocking layer EBL2 in the second light emitting device 20b.
[0095] 4) The thickness of the second light emitting layer EML2 in the first light emitting device 20a is different from the thickness of the second light emitting layer EML2 in the second light emitting device 20b.
[0096] Optionally, within the first light-emitting device 20a, the thickness of the second electron blocking layer EBL2 in the second light-emitting unit 24 is greater than the thickness of the first electron blocking layer EBL1 in the first light-emitting unit 22. The first electron blocking layer EBL1 is located on the side of the first light-emitting layer EML1 facing away from the charge generation layer 23, and the second electron blocking layer EBL2 is located on the side of the second light-emitting layer EML2 closer to the charge generation layer 23. Thus, within the first light-emitting device 20a, the relative thickness trend of the second electron blocking layer EBL2 and the first electron blocking layer EBL1 is opposite to the relative thickness trend of the second light-emitting layer EML2 and the first light-emitting layer EML1. This prevents excessive variation in the cavity length of the microcavity of the first light-emitting device 20a, ensuring that the cavity length of the microcavity of the first light-emitting device 20a is compatible with the wavelength range of light emitted by the first light-emitting device 20a.
[0097] In some possible implementations, in the first light-emitting device 20a, the sum of the thickness of the second electron blocking layer EBL2 and the thickness of the second light-emitting layer EML2 is equal to the sum of the thickness of the first electron blocking layer EBL1 and the thickness of the first light-emitting layer EML1. This ensures that the cavity length of the microcavity of the first light-emitting device 20a remains unchanged, thereby enabling the microcavity of the first light-emitting device 20a to have a better light enhancement effect.
[0098] Compared to Figure 2 In the display panel A provided by the related art shown, the thickness of the second light-emitting layer EML2 in the second light-emitting device 20 b may be less than the thickness of the second light-emitting layer EML2 in the display panel A. Moreover, the sum of the thickness of the second electron blocking layer EBL2 and the thickness of the second light-emitting layer EML2 in the first light-emitting device 20 a may be equal to the sum of the thickness of the second electron blocking layer EBL2 and the thickness of the second light-emitting layer EML2 in the display panel A.
[0099] The following describes various implementations of adjusting the turn-on voltage of the second light-emitting device 20b:
[0100] In the first implementation, please refer to Figure 5 and Figure 6 , Figure 5 is a structural diagram of another display panel provided in an embodiment of the present application. Figure 6 This is a schematic diagram of the structure of another display panel provided by an embodiment of the present application. The first light-emitting unit 22 in the second light-emitting device 20b includes a first light-emitting layer EML1 and an organic functional layer 221. The organic functional layer 221 is located on a side of the first light-emitting layer EML1 facing away from the charge generation layer 23, and the organic functional layer 221 is in direct contact with the first light-emitting layer EML1.
[0101] The second light-emitting unit 24 in the second light-emitting device 20b includes a second light-emitting layer EML2 and a second electron blocking layer EBL2. The second electron blocking layer EBL2 is located on the side of the second light-emitting layer EML2 facing the charge generation layer 23, and the second electron blocking layer EBL2 is in direct contact with the second light-emitting layer EML2. Here, the organic functional layer 221 is disposed in a position similar to that of the second electron blocking layer EBL2 in the second light-emitting unit 24.
[0102] The thickness of the second electron blocking layer EBL2 is greater than that of the organic functional layer 221. Here, the greater the thickness of the second electron blocking layer EBL2, the greater the resistance of the second electron blocking layer EBL2, thereby increasing the turn-on voltage of the second light emitting unit 24 in the second light emitting device 20b.
[0103] In the embodiment of the present application, the film configuration of the organic functional layer 221 includes various situations:
[0104] In the first case, please refer to Figure 5 , the organic functional layer 221 is the auxiliary hole transport layer HTL3. That is, within the second light-emitting device 20b, the side of the first light-emitting layer EML1 in the first light-emitting unit 22 facing away from the charge generation layer 23 is in direct contact with the auxiliary hole transport layer HTL3. Here, the materials of the auxiliary hole transport layer HTL3 in the two second light-emitting devices 20b emitting red and green light, respectively, can be the same or different.
[0105] In the second light-emitting device 20b, the side of the first light-emitting layer EML1 in the first light-emitting unit 22 facing the charge generation layer 23 is in direct contact with the first electron transport layer ETL1. In the first light-emitting device 20a, the side of the first light-emitting layer EML1 in the first light-emitting unit 22 facing away from the charge generation layer 23 is in direct contact with the first electron blocking layer EBL1, and the side of the first light-emitting layer EML1 in the first light-emitting unit 22 facing the charge generation layer 23 is in direct contact with the first hole blocking layer HBL1.
[0106] Therefore, for the first case, that is, in the second light-emitting device 20b, the first electron blocking layer EBL1 and the first hole blocking layer HBL1 are not set in the first light-emitting unit 22. This can reduce the resistance of the film layer in the first light-emitting unit 22, so that the turn-on voltage of the second light-emitting unit 24 can be increased while the turn-on voltage of the first light-emitting unit 22 can be simultaneously reduced, thereby avoiding the overall turn-on voltage of the second light-emitting device 20b being too high, thereby reducing the power consumption of the display panel 00.
[0107] Optionally, the first light-emitting unit 22 in the second light-emitting device 20b further includes a first hole transport layer HTL1 located on the side of the auxiliary hole transport layer HTL3 facing away from the first light-emitting layer EML1. The materials of the auxiliary hole transport layer HTL3 and the first hole transport layer HTL1 may be the same or different. For example, the energy levels of the auxiliary hole transport layer HTL3 and the first hole transport layer HTL1 may vary in a stepwise manner, thereby facilitating hole transport.
[0108] The first light-emitting unit 22 in the first light-emitting device 20 a further includes a first hole transport layer HTL1 located on a side of the first electron blocking layer EBL1 away from the first light-emitting layer EML1 .
[0109] The first hole transport layer HTL1 in the second light emitting device 20 b and the first hole transport layer HTL1 in the first light emitting device 20 a are of the same layer structure. That is, the first hole transport layer HTL1 can be a film layer structure shared by multiple light emitting devices 20 .
[0110] Optionally, the thickness of the second electron blocking layer EBL2 in the second light-emitting device 20b is equal to the sum of the thickness of the auxiliary hole transport layer HTL3 in the second light-emitting device 20b and the thickness of the first hole blocking layer HBL1 in the first light-emitting device 20a. This configuration can prevent the cavity length of the microcavity of the second light-emitting device 20b from varying significantly, ensuring that the cavity length of the microcavity of the first light-emitting device 20a is compatible with the wavelength range of the light emitted by the first light-emitting device 20a.
[0111] Compared to Figure 2In the display panel A provided by the related art, within the second light-emitting device 20 b, the first electron blocking layer EBL1 and the first hole blocking layer HBL1 are not provided in the first light-emitting unit 22, and the first electron blocking layer EBL1 is replaced by an auxiliary hole transport layer HTL3. The thickness of the auxiliary hole transport layer HTL3 can be equal to the thickness of the first electron blocking layer EBL1 in the display panel A. Therefore, when the above conditions are met, the cavity length of the microcavity of the second light-emitting device 20 b can remain unchanged.
[0112] In the second case, please refer to Figure 6 The organic functional layer 221 is a first electron blocking layer. That is, in the second light-emitting device 20b, the side of the first light-emitting layer EML1 in the first light-emitting unit 22 facing away from the charge generation layer 23 is in direct contact with the first electron blocking layer.
[0113] In the second light-emitting device 20b, the side of the first light-emitting layer EML1 in the first light-emitting unit 22 facing the charge generation layer 23 is in direct contact with the first electron transport layer ETL1. In the first light-emitting device 20a, the side of the first light-emitting layer EML1 in the first light-emitting unit 22 facing away from the charge generation layer 23 is in direct contact with the first electron blocking layer EBL1, and the side of the first light-emitting layer EML1 in the first light-emitting unit 22 facing the charge generation layer 23 is in direct contact with the first hole blocking layer HBL1.
[0114] Therefore, for the second case, that is, in the second light-emitting device 20b, the first hole blocking layer HBL1 is not set in the first light-emitting unit 22, so that the resistance of the film layer in the first light-emitting unit 22 can be reduced, so that the turn-on voltage of the second light-emitting unit 24 can be increased while the turn-on voltage of the first light-emitting unit 22 can be simultaneously reduced, thereby avoiding the overall turn-on voltage of the second light-emitting device 20b being too high, thereby reducing the power consumption of the display panel 00.
[0115] Optionally, the thickness of the second electron blocking layer EBL2 in the second light-emitting device 20b is equal to the sum of the thickness of the first electron blocking layer EBL1 in the second light-emitting device 20b and the thickness of the first hole blocking layer HBL1 in the first light-emitting device 20a. This configuration can maintain the cavity length of the microcavity of the second light-emitting device 20b unchanged, ensuring that the cavity length of the microcavity of the first light-emitting device 20a is compatible with the wavelength range of the light emitted by the first light-emitting device 20a.
[0116] In the second implementation, please refer to Figure 5 and Figure 6, the energy level difference between the highest occupied molecular orbital (HOMO) of the second electron blocking layer EBL2 in the second light-emitting device 20b and the second light-emitting layer EML2 in the second light-emitting device 20b is greater than or equal to 0.2 volts. In other words, the potential barrier difference between the second electron blocking layer EBL2 and the second light-emitting layer EML2 in the second light-emitting device 20b is increased, thereby increasing the turn-on voltage of the second light-emitting unit 24 in the second light-emitting device 20b.
[0117] It should be noted that if Figure 5 and Figure 6 As shown, the second implementation method of adjusting the turn-on voltage of the second light-emitting device can be implemented simultaneously with the first implementation method of adjusting the turn-on voltage of the second light-emitting device, but the present application is not limited thereto.
[0118] In some exemplary embodiments, the second method of adjusting the turn-on voltage of the second light emitting device can also be implemented separately, please refer to Figure 7 , Figure 7 This is a schematic diagram of the structure of another display panel provided by an embodiment of the present application. In the second light-emitting device 20b, the thickness of the second electron blocking layer EBL2 can be equal to the thickness of the organic functional layer 221. In other words, the thickness of the second electron blocking layer EBL2 remains unchanged. Thus, even when the second implementation is implemented alone, the turn-on voltage of the second light-emitting unit 24 in the second light-emitting device 20b can be increased.
[0119] Optionally, when the second embodiment is implemented alone, the organic functional layer 221 is the auxiliary hole transport layer HTL3. That is, in the second light-emitting device 20b, the side of the first light-emitting layer EML1 in the first light-emitting unit 22 facing away from the charge generation layer 23 is in direct contact with the auxiliary hole transport layer HTL3. In the second light-emitting device 20b, the side of the first light-emitting layer EML1 in the first light-emitting unit 22 facing toward the charge generation layer 23 is in direct contact with the first hole blocking layer HBL1. In the first light-emitting device 20a, the side of the first light-emitting layer EML1 in the first light-emitting unit 22 facing away from the charge generation layer 23 is in direct contact with the first electron blocking layer EBL1, and the side of the first light-emitting layer EML1 in the first light-emitting unit 22 facing toward the charge generation layer 23 is in direct contact with the first hole blocking layer HBL1.
[0120] That is, in the second light-emitting device 20b, the first electron blocking layer EBL1 is not provided in the first light-emitting unit 22, so that the resistance of the film layer in the first light-emitting unit 22 can be reduced, so that the turn-on voltage of the first light-emitting unit 22 can be reduced simultaneously while the turn-on voltage of the second light-emitting unit 24 is increased, thereby avoiding the overall turn-on voltage of the second light-emitting device 20b from being too high, thereby reducing the power consumption of the display panel 00.
[0121] In the third implementation, please refer to Figure 5 , Figure 6 and Figure 7 In the second light-emitting device 20b, the materials of the first light-emitting layer EML1 in the first light-emitting unit 22 and the second light-emitting layer EML2 in the second light-emitting unit 24 both include a P-type host material and an N-type host material. For the first and second light-emitting layers EML1 and EML2 in the second light-emitting device 20b, a greater content of the P-type host material results in a greater resistance of the first and second light-emitting layers EML1 and EML2.
[0122] In the second light-emitting device 20b, the ratio of the content of the P-type host material to the content of the N-type host material in the second light-emitting layer EML2 is greater than the ratio of the content of the P-type host material to the content of the N-type host material in the first light-emitting layer EML1. In other words, the embodiment of the present application can increase the content of the P-type host material in the second light-emitting layer EML2 in the second light-emitting device 20b, thereby increasing the resistance of the second light-emitting layer EML2 in the second light-emitting device 20b, and thus increasing the turn-on voltage of the second light-emitting unit 24 in the second light-emitting device 20b.
[0123] For example, in the second light-emitting device 20 b , the ratio of the content of the P-type host material to the content of the N-type host material in the second light-emitting layer EML2 may satisfy:
[0124] 5:5≤P:N≤8:2;
[0125] Wherein, P is the content of the P-type host material in the second light-emitting layer EML2 within the second light-emitting device 20b, and N is the content of the N-type host material in the second light-emitting layer EML2 within the second light-emitting device 20b. By limiting this ratio (P:N) to be greater than or equal to 5:5, the content of the P-type host material in the second light-emitting layer EML2 within the second light-emitting device 20b can be increased. By limiting this ratio (P:N) to be less than or equal to 8:2, the content of the N-type host material in the second light-emitting layer EML2 within the second light-emitting device 20b can be avoided from being too low, thereby avoiding the problem of abnormal light emission.
[0126] It should be noted that the third implementation method of adjusting the turn-on voltage of the second light-emitting device can be implemented simultaneously with at least one of the above-mentioned first implementation method and the above-mentioned second implementation method, but the present application is not limited thereto.
[0127] In some exemplary embodiments, the third method of adjusting the turn-on voltage of the second light emitting device can also be implemented separately, please refer to Figure 7 In the second light-emitting device 20b, the thickness of the second electron blocking layer EBL2 can be equal to the thickness of the organic functional layer 221. In other words, the thickness of the second electron blocking layer EBL2 remains unchanged. Furthermore, the embodiment of the present application does not impose any restrictions on the HOMO energy level difference between the second electron blocking layer EBL2 and the second light-emitting layer EML2 in the second light-emitting device 20b. Thus, even when the third implementation is implemented alone, the turn-on voltage of the second light-emitting unit 24 in the second light-emitting device 20b can still be increased.
[0128] Optionally, when the third embodiment is implemented alone, the organic functional layer 221 is an auxiliary hole transport layer HTL3. That is, in the second light-emitting device 20b, the side of the first light-emitting layer EML1 in the first light-emitting unit 22 facing away from the charge generation layer 23 is in direct contact with the auxiliary hole transport layer HTL3. In the second light-emitting device 20b, the side of the first light-emitting layer EML1 in the first light-emitting unit 22 facing toward the charge generation layer 23 is in direct contact with the first hole blocking layer HBL1. In the first light-emitting device 20a, the side of the first light-emitting layer EML1 in the first light-emitting unit 22 facing away from the charge generation layer 23 is in direct contact with the first electron blocking layer EBL1, and the side of the first light-emitting layer EML1 in the first light-emitting unit 22 facing toward the charge generation layer 23 is in direct contact with the first hole blocking layer HBL1.
[0129] That is, in the second light-emitting device 20b, the first electron blocking layer EBL1 is not provided in the first light-emitting unit 22, so that the resistance of the film layer in the first light-emitting unit 22 can be reduced, so that the turn-on voltage of the first light-emitting unit 22 can be reduced simultaneously while the turn-on voltage of the second light-emitting unit 24 is increased, thereby avoiding the overall turn-on voltage of the second light-emitting device 20b from being too high, thereby reducing the power consumption of the display panel 00.
[0130] It should be noted that if Figure 4 As shown, the above-mentioned method for adjusting the turn-on voltage of the first light-emitting device 20a can be implemented alone. Alternatively, the above-mentioned method for adjusting the turn-on voltage of the first light-emitting device 20a can also be implemented in combination with at least one of the above-mentioned methods for adjusting the turn-on voltage of the second light-emitting device 20b, which will not be described in detail here.
[0131] In an exemplary embodiment, please refer to Figure 8 , Figure 8 2 is a schematic diagram of the structure of another display panel provided by an embodiment of the present application. Within the first light-emitting device 20a, the thickness of the second light-emitting layer EML2 in the second light-emitting unit 24 is less than the thickness of the first light-emitting layer EML1 in the first light-emitting unit 22. Furthermore, within the second light-emitting device 20b, the thickness of the second electron blocking layer EBL2 can be equal to the thickness of the organic functional layer 221, which serves as the auxiliary hole transport layer HTL3. Thus, within the second light-emitting device 20b, the first light-emitting layer EML1 of the first light-emitting unit 22, facing away from the charge generation layer 23, is in direct contact with the auxiliary hole transport layer HTL3. In other words, within the second light-emitting device 20b, the first light-emitting unit 22 is not provided with the first electron blocking layer EBL1. This reduces the resistance of the film layers in the first light-emitting unit 22, thereby lowering the turn-on voltage of the first light-emitting unit 22 within the second light-emitting device 20b and, in turn, reducing the power consumption of the display panel 200.
[0132] In summary, the embodiments of the present application provide a display panel, wherein, for a first light-emitting device and a second light-emitting device of different types, by adjusting the voltage between the charge generation layer and the second electrode in the second light-emitting device, or adjusting the turn-on voltage of the second light-emitting unit in the second light-emitting device, it is possible to make the voltage between the charge generation layer and the second electrode in the second light-emitting device less than the turn-on voltage of the second light-emitting unit in the second light-emitting device during the light-emitting process of the first light-emitting device, thereby ensuring that the leakage current is insufficient to light up the second light-emitting unit in the second light-emitting device, thereby avoiding the problem of lateral crosstalk and further improving the color purity of the display panel.
[0133] In another aspect, embodiments of the present application further provide a display device, which may include a display panel according to any of the above embodiments. The display device may be any device including a display function, such as a mobile phone, tablet, wearable device, television, or vehicle-mounted display device.
[0134] Since the display device includes the display panel provided by the above embodiment, the display device can also have a similar effect, that is, it can avoid the horizontal crosstalk problem.
[0135] In this application, the term "and / or" simply describes an association between related objects, indicating that three possible relationships exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this document generally indicates that the related objects are in an "or" relationship.
[0136] In this application, the term "at least one of A and B" simply describes an association relationship between associated objects, indicating that three possible relationships exist. For example, "at least one of A and B" can mean: A exists alone, A and B exist simultaneously, and B exists alone. Similarly, "at least one of A, B, and C" means that seven possible relationships exist, indicating: A exists alone, B exists alone, C exists alone, A and B exist simultaneously, A and C exist simultaneously, C and B exist simultaneously, and A, B, and C exist simultaneously. Similarly, "at least one of A, B, C, and D" means that fifteen possible relationships exist, indicating: A exists alone, B exists alone, C exists alone, D exists alone, A and B exist simultaneously, A and C exist simultaneously, A and D exist simultaneously, C and B exist simultaneously, D and B exist simultaneously, C and D exist simultaneously, C and D exist simultaneously, A, B, and C exist simultaneously, A, B, and D exist simultaneously, A, C, and D exist simultaneously, B, C, and D exist simultaneously, and A, B, C, and D exist simultaneously.
[0137] It should be noted that in the accompanying drawings, the sizes of layers and regions may be exaggerated for clarity of illustration. It will also be understood that when an element or layer is referred to as being "on" another element or layer, it may be directly on the other element, or there may be an intermediate layer. In addition, it will be understood that when an element or layer is referred to as being "under" another element or layer, it may be directly under the other element, or there may be more than one intermediate layer or element. In addition, it will also be understood that when a layer or element is referred to as being "between" two layers or elements, it may be the only layer between the two layers or elements, or there may also be more than one intermediate layer or element. Similar reference numerals throughout the text indicate similar elements.
[0138] In this application, the terms "first", "second" and "third" are used for descriptive purposes only and should not be understood as indicating or implying relative importance. The term "plurality" refers to two or more than two, unless expressly limited otherwise.
[0139] The above description is merely an optional embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application shall be included in the scope of protection of the present application.
Claims
1. A display panel, characterized in that: The display panel includes: a driving backplane and a plurality of light-emitting devices; The light-emitting device includes: a first electrode, a first light-emitting unit, a charge generation layer, a second light-emitting unit, and a second electrode; the first electrode is located on one side of the driving backplane and is electrically connected to the driving backplane; the second electrode is located on a side of the first electrode away from the driving backplane; the first light-emitting unit, the charge generation layer, and the second light-emitting unit are stacked between the first electrode and the second electrode, with the first light-emitting unit being closer to the driving backplane than the second light-emitting unit; the first light-emitting unit and the second light-emitting unit in the same light-emitting device emit the same light color; Among them, for a first light-emitting device and a second light-emitting device that are adjacently distributed and of different types among the multiple light-emitting devices, during the light-emitting process of the first light-emitting device, the voltage between the charge generation layer and the second electrode in the second light-emitting device is less than the turn-on voltage of the second light-emitting unit in the second light-emitting device.
2. The display panel according to claim 1, wherein: A turn-on voltage of the first light emitting device is greater than a turn-on voltage of the second light emitting device; The turn-on voltage of the second light-emitting unit in the first light-emitting device is lower than the turn-on voltage of the first light-emitting unit, and / or the turn-on voltage of the second light-emitting unit in the second light-emitting device is higher than the turn-on voltage of the first light-emitting unit.
3. The display panel according to claim 2, wherein: In the first light-emitting device, a thickness of the second light-emitting layer in the second light-emitting unit is smaller than a thickness of the first light-emitting layer in the first light-emitting unit.
4. The display panel according to claim 3, wherein: In the first light-emitting device, the thickness of the second electron blocking layer in the second light-emitting unit is greater than the thickness of the first electron blocking layer in the first light-emitting unit; The first electron blocking layer is located on a side of the first light-emitting layer away from the charge generation layer, and the second electron blocking layer is located on a side of the second light-emitting layer close to the charge generation layer.
5. The display panel according to any one of claims 2 to 4, characterized in that: The first light-emitting unit in the second light-emitting device includes: a first light-emitting layer and an organic functional layer, wherein the organic functional layer is located on a side of the first light-emitting layer away from the charge generation layer, and the organic functional layer is in direct contact with the first light-emitting layer; The second light-emitting unit in the second light-emitting device includes: a second light-emitting layer and a second electron blocking layer, wherein the second electron blocking layer is located on a side of the second light-emitting layer facing the charge generation layer, and the second electron blocking layer is in direct contact with the second light-emitting layer; Wherein, the thickness of the second electron blocking layer is greater than the thickness of the organic functional layer.
6. The display panel according to claim 5, wherein: The organic functional layer is an auxiliary hole transport layer; In the second light-emitting device, the side of the first light-emitting layer in the first light-emitting unit facing the charge generation layer is in direct contact with the first electron transport layer; in the first light-emitting device, the side of the first light-emitting layer in the first light-emitting unit facing away from the charge generation layer is in direct contact with the first electron blocking layer, and the side of the first light-emitting layer in the first light-emitting unit facing the charge generation layer is in direct contact with the first hole blocking layer.
7. The display panel according to claim 6, wherein: The first light-emitting unit in the second light-emitting device further includes: a first hole transport layer located on a side of the auxiliary hole transport layer away from the first light-emitting layer; The first light-emitting unit in the first light-emitting device further includes: a first hole transport layer located on a side of the first electron blocking layer away from the first light-emitting layer; The first hole transport layer in the second light-emitting device and the first hole transport layer in the first light-emitting device are of the same layer structure.
8. The display panel according to claim 7, wherein: The thickness of the second electron blocking layer in the second light-emitting device is equal to the sum of the thickness of the auxiliary hole transport layer in the second light-emitting device and the thickness of the first hole blocking layer in the first light-emitting device.
9. The display panel according to claim 5, wherein: The organic functional layer is a first electron blocking layer; In the second light-emitting device, the side of the first light-emitting layer in the first light-emitting unit facing the charge generation layer is in direct contact with the first electron transport layer; in the first light-emitting device, the side of the first light-emitting layer in the first light-emitting unit facing away from the charge generation layer is in direct contact with the first electron blocking layer, and the side of the first light-emitting layer in the first light-emitting unit facing the charge generation layer is in direct contact with the first hole blocking layer.
10. The display panel according to claim 9, wherein: The thickness of the second electron blocking layer in the second light-emitting device is equal to the sum of the thickness of the first electron blocking layer in the second light-emitting device and the thickness of the first hole blocking layer in the first light-emitting device.
11. The display panel according to claim 5, wherein: An energy level difference between the highest occupied molecular orbital of the second electron blocking layer in the second light-emitting device and the second light-emitting layer in the second light-emitting device is greater than or equal to 0.2 volts.
12. The display panel according to any one of claims 2-4, 6-11, characterized in that: In the second light-emitting device, materials of the first light-emitting layer in the first light-emitting unit and the second light-emitting layer in the second light-emitting unit both include: a P-type host material and an N-type host material; In the second light-emitting device, the ratio of the content of the P-type host material to the content of the N-type host material in the second light-emitting layer is greater than the ratio of the content of the P-type host material to the content of the N-type host material in the first light-emitting layer.
13. The display panel according to any one of claims 1-4, 6-11, characterized in that: An absolute value of a difference between a turn-on voltage of the second light-emitting unit in the first light-emitting device and a turn-on voltage of the second light-emitting unit in the second light-emitting device is less than or equal to 0.5V.
14. The display panel according to any one of claims 1-4, 6-11, characterized in that: The first light emitting device emits blue light, and the second light emitting device emits red light or green light.
15. The display panel according to any one of claims 1-4, 6-11, characterized in that: During light emission of the first light emitting device, a voltage between the charge generation layer and the second electrode in the second light emitting device is less than 2.0V.
16. A display device, characterized in that: include: A power supply component, and a display panel electrically connected to the power supply component, wherein the display panel comprises: the display panel according to any one of claims 1 to 15.