Double-layer OLED display unit, display panel and electronic device

Abstract

The present disclosure provides a double-layer OLED display unit, a display panel, and an electronic device, wherein the display unit includes: an anode, a first light-emitting unit, a charge generation layer, a second light-emitting unit, and a cathode; the first light-emitting unit includes a first light-emitting group and a second light-emitting group, the second light-emitting unit includes a third light-emitting group and a fourth light-emitting group, the first light-emitting group has the same color as any one of the third light-emitting group and the fourth light-emitting group, and the second light-emitting group has the same color as the other one of the third light-emitting group and the fourth light-emitting group; in the first light-emitting unit, the energy level difference between the main material and the light-emitting material in the first preset light-emitting group is greater than or equal to a preset threshold; the first preset light-emitting group is the first light-emitting group or the second light-emitting group; in the second light-emitting unit, the energy level difference between the main material and the light-emitting material in the second preset light-emitting group is greater than or equal to the preset threshold, and the second preset light-emitting group is a light-emitting group of the third light-emitting group and the fourth light-emitting group that has a light-emitting color different from that of the first preset light-emitting group.

Description

Technical Field

[0001] The present disclosure relates to the field of display technology, and in particular to a double-layer OLED display unit, a display panel, and an electronic device. Background Art

[0002] The basic structure of an organic light-emitting diode (OLED) device consists of an anode layer (Anode), functional layers, and a cathode layer (Cathode). The functional layers include a hole injection layer (HIL), a hole transport layer (HTL), an emissive layer (EML), and an electron transport layer (ETL). They may also include a hole blocking layer (HBL) and an electron blocking layer (EBL). When an appropriate voltage is applied to the cathode and anode, electrons and holes are injected from the cathode and anode into the electron and hole transport layers, respectively. After migrating to the emissive layer, they recombine and emit light, thus achieving the self-luminous characteristic of the OLED device.

[0003] However, in current OLED display units, when the applied current density increases, the light emitting position of the OLED device will shift, such as Figure 1 As shown, the light output of the red, green, and blue light-emitting layers changes, causing the light ultimately emitted by the OLED unit to shift toward one of the colors, resulting in a color shift. Summary of the Invention

[0004] The purpose of the embodiments of the present disclosure is to provide a double-layer OLED display unit, a display panel, and an electronic device to solve the color shift problem under high and low current densities in the prior art.

[0005] The embodiment of the present disclosure adopts the following technical solution: a double-layer OLED display unit, comprising at least: an anode, a first light-emitting unit, a charge generation layer, a second light-emitting unit, and a cathode stacked in sequence; wherein the first light-emitting unit includes at least a first light-emitting group and a second light-emitting group, and the second light-emitting unit includes at least a third light-emitting group and a fourth light-emitting group, the first light-emitting group has the same light-emitting color as any one of the third light-emitting group and the fourth light-emitting group, and the second light-emitting group has the same light-emitting color as the other one of the third light-emitting group and the fourth light-emitting group; in the first light-emitting unit, the energy level difference between the main material and the light-emitting material in the first preset light-emitting group is greater than or equal to a preset threshold; wherein the first preset light-emitting group is the first light-emitting group or the second light-emitting group; in the second light-emitting unit, the energy level difference between the main material and the light-emitting material in the second preset light-emitting group is greater than or equal to a preset threshold, wherein the second preset light-emitting group is a light-emitting group of the third light-emitting group and the fourth light-emitting group whose light-emitting color is different from that of the first preset light-emitting group.

[0006] In some embodiments, the charge generation layer includes at least: an electron generation layer disposed near the first light emitting unit, and a charge generation layer disposed near the second light emitting unit.

[0007] In some embodiments, the preset threshold is 0.2 eV.

[0008] In some embodiments, a first barrier layer is disposed between the first light-emitting group and the second light-emitting group; and a second barrier layer is disposed between the third light-emitting group and the fourth light-emitting group.

[0009] In some embodiments, the first light-emitting unit and the second light-emitting unit include a red light-emitting layer, a blue light-emitting layer, and a green light-emitting layer, respectively; wherein, one of the first light-emitting group and the second light-emitting group includes two light-emitting layers in direct contact; and one of the third light-emitting group and the fourth light-emitting group includes two light-emitting layers in direct contact.

[0010] In some embodiments, the two light-emitting layers in direct contact are a blue light-emitting layer and a green light-emitting layer.

[0011] In some embodiments, the first light-emitting unit and the second light-emitting unit further include: an electron transport layer, an electron blocking layer, a hole transport layer, and a hole injection layer.

[0012] In some embodiments, the first light-emitting unit includes a hole injection layer, a hole transport layer, an electron blocking layer, a red light-emitting layer, a first barrier layer, a blue light-emitting layer, a green light-emitting layer, and an electron transport layer that are stacked in sequence along a direction away from the anode; the second light-emitting unit includes an electron transport layer, a red light-emitting layer, a second barrier layer, a green light-emitting layer, a blue light-emitting layer, an electron blocking layer, and a hole transport layer that are stacked in sequence along a direction away from the cathode.

[0013] In some embodiments, materials of all light-emitting layers in the first light-emitting unit and the second light-emitting unit are fluorescent materials.

[0014] An embodiment of the present disclosure further provides a display panel, characterized in that the display panel includes at least a plurality of double-layer OLED display units as described above.

[0015] An embodiment of the present disclosure further provides an electronic device, characterized in that the electronic device at least includes the above-mentioned display panel.

[0016] The beneficial effect of the embodiment of the present disclosure is that by stacking two light-emitting units and limiting the two light-emitting units to have different offset colors under high current density, the color deviation effect is weakened after the two different offset colors are superimposed, thereby ensuring that the overall display effect of the OLED display unit is better and the user experience is better. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present disclosure or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments recorded in the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0018] Figure 1 Schematic diagram of the hierarchical structure of an OLED display unit in the prior art;

[0019] Figure 2 Schematic diagram of the hierarchical structure of a double-layer OLED display unit in the first embodiment of the present disclosure;

[0020] Figure 3 Schematic diagram of the energy level difference between host1 and dopant in the first embodiment of the present disclosure;

[0021] Figure 4 Schematic diagram of the energy level difference between host2 and dopant in the first embodiment of the present disclosure;

[0022] Figure 5Voltage variation curves of light-emitting layers made of two different host materials under different currents in the first embodiment of the present disclosure;

[0023] Figure 6 The service life variation curves of the light-emitting layers made of two different host materials in the first embodiment of the present disclosure;

[0024] Figure 7 is a spectrum diagram of sample 1 in the first embodiment of the present disclosure;

[0025] Figure 8 This is a spectrum diagram of sample 2 in the first embodiment of the present disclosure. DETAILED DESCRIPTION

[0026] Various aspects and features of the present disclosure are described herein with reference to the accompanying drawings.

[0027] It should be understood that various modifications may be made to the embodiments disclosed herein. Therefore, the above description should not be considered as limiting, but merely as an example of an embodiment. Other modifications within the scope and spirit of the present disclosure will occur to those skilled in the art.

[0028] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the present disclosure and, together with the general description of the present disclosure given above and the detailed description of the embodiments given below, serve to explain the principles of the present disclosure.

[0029] These and other characteristics of the present disclosure will become apparent from the following description of a preferred form of embodiment given as a non-limiting example with reference to the accompanying drawings.

[0030] It should also be understood that although the present disclosure has been described with reference to certain specific examples, those skilled in the art will be able to realize many other equivalent forms of the present disclosure that have the features of the claims and are therefore within the scope of protection defined thereby.

[0031] The above and other aspects, features and advantages of the present disclosure will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.

[0032] Specific embodiments of the present disclosure will be described hereinafter with reference to the accompanying drawings; however, it should be understood that the claimed embodiments are merely examples of the present disclosure, which may be implemented in a variety of ways. Well-known and / or repetitive functions and structures are not described in detail to avoid obscuring the present disclosure with unnecessary or redundant detail. Therefore, the specific structural and functional details claimed herein are not intended to be limiting, but rather serve merely as a basis and representative basis for teaching those skilled in the art to variously employ the present disclosure with substantially any suitable detailed structure.

[0033] This description may use the phrases "in one embodiment," "in another embodiment," "in a further embodiment," or "in other embodiments," each of which may refer to one or more of the same or different embodiments according to the present disclosure.

[0034] In current OLED display units, when the current density applied to them increases, the light-emitting position of the OLED device will shift, causing the light output of its red, green, and blue light-emitting layers to change, causing the light ultimately emitted by the OLED unit to shift toward one of the colors, resulting in color shift. Figure 1 In the OLED structure shown in , host represents the main material of each light-emitting layer, and RD, GD, and BD represent the red, green, and blue light-emitting materials, respectively. According to the current setting position of the light-emitting layer, under high current density, the light-emitting area moves to the left, causing the OLED unit to eventually have a red color cast.

[0035] In order to solve the above problems, the first embodiment of the present disclosure provides a double-layer OLED display unit, the structural diagram of which is shown in FIG. Figure 2 As shown. Figure 2 In the embodiment, the double-layer OLED display unit mainly includes an anode 30, a first light-emitting unit 10, a charge generation layer 40 (CGL), a second light-emitting unit 20, and a cathode 50, which are stacked in sequence. That is, the first light-emitting unit 10 and the second light-emitting unit 20 are stacked, and a charge generation layer 40 is added between the two as the cathode corresponding to the first light-emitting unit 10 and the anode corresponding to the second light-emitting unit, forming a double-layer OLED display unit. Furthermore, the charge generation layer 40 is divided into an electron generation layer 41 arranged near the first light-emitting unit 10, which acts as the cathode of the first light-emitting unit 10 to transfer electrons to the first light-emitting unit, and also includes a hole generation layer 42 arranged near the second light-emitting unit 20, which acts as the anode of the second light-emitting unit 20 to inject holes into the second light-emitting unit, thereby forming two independent and complete light-emitting units to achieve light emission.

[0036] Specifically, the first and second light-emitting units 10 and 20 are each configured to emit white light to achieve the display function of the display unit. Each light-emitting unit comprises at least two light-emitting groups for emitting light of different colors. The first light-emitting unit 10 includes at least a first light-emitting group 11 and a second light-emitting group 12, while the second light-emitting unit 20 includes at least a third light-emitting group 21 and a fourth light-emitting group 22. In this embodiment, the color of light emitted by the first light-emitting group 11 is the same as the color of light emitted by either the third light-emitting group 21 or the fourth light-emitting group 22, while the color of light emitted by the second light-emitting group 12 is the same as the color of light emitted by the other of the third light-emitting group 21 and the fourth light-emitting group 22. In actual implementation, one of the two light-emitting groups in each light-emitting unit is always closer to the anode of the unit, while the other is closer to the cathode. Therefore, when the light-emitting layers in the light-emitting groups are made of different materials, the direction of the light-emitting area shift may also vary. Therefore, in this embodiment, the light-emitting layers of the three colors are divided into two groups, which facilitates the control of the direction of the light-emitting area shift. The shift can be controlled by simply shifting the light-emitting layer to the position of either of the two light-emitting groups.

[0037] Generally, a light-emitting unit includes at least three light-emitting layers of different colors, namely red (R), blue (B) and green (G), and one of the two light-emitting groups included in the light-emitting unit includes a light-emitting layer of one color, and the other light-emitting group includes light-emitting layers of the remaining two colors, and the light-emitting layers in the light-emitting groups with one light-emitting layer in the two light-emitting units have the same color. For example, the first light-emitting group 11 includes a red light-emitting layer, the second light-emitting group 12 includes a blue light-emitting layer and a green light-emitting layer, the third light-emitting group 21 includes a blue light-emitting layer and a green light-emitting layer, and the fourth light-emitting group 22 includes a red light-emitting layer. The light-emitting layers of the first light-emitting group 11 and the fourth light-emitting group 22 have the same color, and the light-emitting layers of the second light-emitting group 12 and the third light-emitting group 21 have the same color. It should be noted that in the second light-emitting group 12 and the third light-emitting group 21, the blue light-emitting layer and the green light-emitting layer are directly in contact. When the light-emitting region is shifted to the position of the second light-emitting group 12 or the third light-emitting group 21, due to the direct contact between the blue and green light-emitting layers and the energy difference between them, they generally emit light simultaneously, resulting in the light emitted by the corresponding light-emitting group being a mixture of blue and green. Furthermore, the colors of the two light-emitting layers included in the light-emitting groups described in this embodiment can be any two of the three primary colors, as long as the light-emitting groups in the two light-emitting units contain the same colors. The specific two colors are not limited.

[0038] In some embodiments, as Figure 2As shown, a first barrier layer 13 is disposed between the first light-emitting group 11 and the second light-emitting group 12, and a second barrier layer 23 is disposed between the third light-emitting group 21 and the fourth light-emitting group 22. Both barrier layers are used to facilitate energy transfer between the light-emitting layers within the light-emitting groups, preventing the emission of one light-emitting group from driving the emission of another light-emitting group within the unit, which could result in color deviations in the light-emitting units. In actual production, both the first barrier layer 13 and the second barrier layer 23 can be made of 4,4'-cyclohexylbis[N,N-di(4-methylphenyl)aniline] (TAPC) or 1,3-dicarbazol-9-ylbenzene (mCP), or other materials with the same functionality, without limitation in this embodiment.

[0039] In this embodiment, the offset position of the light-emitting region of the light-emitting unit under high-density current is controlled by limiting the energy level difference between the host material and the light-emitting material of the light-emitting group. Specifically, when the energy level difference between the host material and the light-emitting material of the light-emitting layer in one of the light-emitting groups A of the light-emitting unit is greater than or equal to a preset threshold, the corresponding light-emitting material has a binding effect on holes or electrons, causing the holes or electrons to be bound in the light-emitting layer A. At this time, the electrons or holes injected into the light-emitting unit from the other end need to move to the light-emitting layer A to combine with the bound holes or electrons to emit light, thereby increasing the brightness of the light emitted by the light-emitting layer A. When the brightness of the light of another light-emitting group B in the same light-emitting unit remains unchanged, the color presented by the light-emitting unit as a whole will shift toward the color of the light-emitting layer A, resulting in color shift. When two light-emitting units are superimposed, as long as the color offset by the first light-emitting unit 10 is controlled to be different from the color offset by the second light-emitting unit 20, the two different colors will weaken the overall color deviation effect of the display unit after superposition, so that the ratio of different colors is basically balanced. Finally, the white light effect presented by the display unit is better, and color deviation problems will not occur when the high and low current densities change, ensuring that the overall display effect presented by the OLED display unit is better and the user experience is better.

[0040] Specifically, in the first light-emitting unit 10, the energy level difference between the main material and the luminescent material defining the first preset luminescent group is greater than or equal to a preset threshold, wherein the first preset luminescent group can be either the first luminescent group 11 or the second luminescent group 12. In the second light-emitting unit 20, the energy level difference between the main material and the luminescent material defining the second preset luminescent group is greater than or equal to the preset threshold, wherein the second preset luminescent group is a luminescent group of the third luminescent group 21 and the fourth luminescent group 22 that emits a different color than the first preset luminescent group. For example, if the first luminescent group 11 is the first preset luminescent group and includes a red luminescent layer, and in the second light-emitting unit 20, the third luminescent group 21 includes a blue luminescent layer and a green luminescent layer, and the fourth luminescent group 22 includes a red luminescent layer, then the second preset luminescent group is the third luminescent group 21, and it can be configured to emit a different color than the first preset luminescent group.

[0041] In actual implementation, different main materials and luminescent materials can be selected according to the positions of the first preset luminescent group and the second preset luminescent group, so that the energy level difference between the two is greater than or equal to the preset threshold value. When the preset luminescent group is located on the cathode 50 side close to the display unit, the luminescent material and main material with a stronger binding effect on electrons can be selected to make the luminescent layer, and when the preset luminescent group is located on the anode 30 side close to the display unit, the luminescent material and main material with a stronger binding effect on holes can be selected to make the luminescent layer. The selection of specific materials can be selected according to actual factors such as material properties or material costs, and this embodiment does not impose specific restrictions.

[0042] In some embodiments, the preset threshold is generally set to 0.2 eV, that is, the energy level difference between the host material and the light-emitting material in the preset light-emitting group is greater than or equal to 0.2 eV to achieve the confinement of holes or electrons. Figure 3 and Figure 4 A schematic diagram shows the energy level difference between two different host materials and the luminescent material when the luminescent material remains unchanged, wherein the energy level difference between host1 and dopant is 0.7 eV, and the energy level difference between host2 and dopant is 0.2 eV. The energy level differences are both greater than the preset threshold, that is, both have a binding effect on holes or electrons.

[0043] Figure 5 The figure shows the voltage (V) variation curves of the light-emitting layer made of the two different host materials at different currents (J). Figure 5 As shown, the right curve represents the voltage change of the light-emitting layer made by host1 under different currents, and the left curve represents the voltage change of the light-emitting layer made by host2 under different currents. Figure 5It can be seen that when the energy level difference between the host and dopant increases, the material's ability to bind holes or electrons increases, which slows down the transmission of holes or electrons, resulting in an increase in the resistance of the light-emitting layer and an increase in voltage, which in turn requires greater energy consumption.

[0044] at the same time, Figure 6 The graph shows the lifespan change curve of the light-emitting layer made of the two different host materials. In this embodiment, the change of the lifespan is represented by the change of the brightness of the light-emitting layer. Figure 6 As shown, the lower curve is the service life change of the light-emitting layer made by host1, and the upper curve is the service life change of the light-emitting layer made by host2. Figure 6 It can be seen that when the energy level difference between the host and dopant increases, the material's ability to bind holes or electrons increases, which can easily cause the luminescence brightness of the light-emitting layer to decrease over time, that is, shorten the lifespan, affecting the normal use of the device. From this, it can be seen that although a larger energy level difference between the host material and the light-emitting material strengthens the binding of holes or electrons, it may also increase energy consumption and damage the device lifespan. Therefore, when selecting materials, it is sufficient to ensure that the energy level difference between the host and dopant is within 0.2eV.

[0045] In addition, if Figure 2 The structure of the double-layer OLED display unit shown in the figure also includes an electron transport layer ETL, an electron blocking layer EBL, a hole transport layer HTL, a hole injection layer HIL, etc., which are used to realize the corresponding electron or hole transmission or blocking function in the OLED light-emitting unit. The specific position of each layer can be directly designed according to the position of each layer in the OLED unit in the prior art, and will not be described in detail in this embodiment. In some embodiments, the materials of all light-emitting layers of the first light-emitting unit 10 and the second light-emitting unit 20 are fluorescent materials. Compared with phosphorescent materials, the light-emitting units produced have a longer service life, further reducing the production and maintenance costs of the light-emitting units.

[0046] In actual production, you can follow the Figure 2 In the manner shown, a hole injection layer, a hole transport layer, a red light-emitting layer, a first blocking layer 13, a blue light-emitting layer, a green light-emitting layer and an electron transport layer are stacked in sequence on the side away from the anode 30 to serve as a first light-emitting unit 10, and an electron transport layer, a red light-emitting layer, a second blocking layer 23, a green light-emitting layer, a blue light-emitting layer, an electron blocking layer and a hole transport layer are stacked in sequence in a direction away from the cathode 40 to form a second light-emitting unit 20, and a charge generation layer 40 is provided between the first light-emitting unit 10 and the second light-emitting unit 20 to achieve the effect of simultaneous light-emitting of the two light-emitting units.

[0047] In this embodiment, two light-emitting units are stacked and set, and the two light-emitting units are limited to different colors offset at high current density, so that the color deviation effect is weakened after the two different offset colors are superimposed, thereby ensuring that the overall display effect of the OLED display unit is better and the user experience is better.

[0048] The display effect of the double-layer OLED display unit provided in this embodiment will be described below in conjunction with a control sample.

[0049] Sample 1 is an OLED light-emitting unit made based on the existing technology. Its optical parameters under the conditions of applied current density of 10J and 100J are shown in Table 1, and its corresponding spectrum is shown in Figure 7 As shown:

[0050]

[0051] Sample 2 is a double-layer OLED display unit manufactured based on the solution in this embodiment. Its optical parameters under the conditions of applied current density of 10J and 100J are shown in Table 2, and its corresponding spectrum is shown in Table 2. Figure 8 As shown:

[0052]

[0053] Based on Table 1 and Figure 7 From the results of Table 2 and Table 3, we can see that when the applied current density increases, the proportion of red light in the spectrum of sample 1 increases, causing the color of the light it emits to be reddish, with a specific color deviation value of 0.012. Figure 8 As can be seen from the content, the spectral shape corresponding to Sample 2 when the applied current density increases is basically the same as that at low current density, and the color deviation value is only 0.006, which is an order of magnitude lower than the color deviation of Sample 1. For actual display effects, the color deviation effect of Sample 2 is basically imperceptible to users, and it has a better display effect.

[0054] The second embodiment of the present disclosure provides a display panel that includes at least a plurality of the double-layer OLED display units described in the first embodiment. The plurality of display units can be arranged in an array to form a display panel to ensure that when the brightness of the display panel is increased (i.e., the current density is increased), the color displayed by the display panel will not exhibit color deviation, thereby improving the display effect of the display panel and providing a better user experience. It should be noted that the display panel may also include other hierarchical structures for realizing the functions of the display panel, such as a touch layer, electrodes, data lines, a cover plate, etc., which can be added according to actual needs and are not limited by this embodiment.

[0055] The third embodiment of the present disclosure provides an electronic device, which can be a device with a display function such as a mobile phone, a computer monitor, a watch, or a television, and the electronic device includes at least the display panel provided by the second embodiment of the present disclosure to ensure that when the display brightness of the electronic device is increased (i.e., the current density is increased), the final display effect does not have color deviation, and has a better user viewing experience. It should be understood that the electronic device should also include devices or structures for realizing other functions of the electronic device, which can be added or set according to actual needs, and this embodiment does not limit them.

[0056] The above describes in detail multiple embodiments of the present disclosure, but the present disclosure is not limited to these specific embodiments. Those skilled in the art can make various variations and modifications to the embodiments based on the concepts of the present disclosure, and these variations and modifications should all fall within the scope of protection claimed by the present disclosure.

Claims

1. A double-layer OLED display unit, characterized in that: At least: An anode, a first light-emitting unit, a charge generation layer, a second light-emitting unit, and a cathode are stacked in sequence; wherein, The first light-emitting unit includes at least a first light-emitting group and a second light-emitting group, the second light-emitting unit includes at least a third light-emitting group and a fourth light-emitting group, the first light-emitting group emits the same light color as any one of the third light-emitting group and the fourth light-emitting group, and the second light-emitting group emits the same light color as the other of the third light-emitting group and the fourth light-emitting group; In the first light-emitting unit, an energy level difference between a host material and a light-emitting material in a first preset light-emitting group is greater than or equal to a preset threshold; wherein the first preset light-emitting group is the first light-emitting group or the second light-emitting group; In the second light-emitting unit, the energy level difference between the main material and the light-emitting material in the second preset light-emitting group is greater than or equal to a preset threshold, wherein the second preset light-emitting group is a light-emitting group among the third light-emitting group and the fourth light-emitting group whose light-emitting color is different from that of the first preset light-emitting group.

2. The double-layer OLED display unit according to claim 1, characterized in that: The charge generation layer comprises at least: An electron generation layer is disposed adjacent to the first light emitting unit, and a charge generation layer is disposed adjacent to the second light emitting unit.

3. The double-layer OLED display unit according to claim 1, wherein: The preset threshold is 0.2 eV.

4. The double-layer OLED display unit according to claim 1, wherein: A first barrier layer is provided between the first light-emitting group and the second light-emitting group; A second barrier layer is disposed between the third light-emitting group and the fourth light-emitting group.

5. The double-layer OLED display unit according to claim 4, characterized in that: The first light-emitting unit and the second light-emitting unit include a red light-emitting layer, a blue light-emitting layer and a green light-emitting layer respectively; wherein, One of the first light-emitting group and the second light-emitting group includes two light-emitting layers that are in direct contact with each other; and one of the third light-emitting group and the fourth light-emitting group includes two light-emitting layers that are in direct contact with each other.

6. The double-layer OLED display unit according to claim 5, characterized in that: The two light-emitting layers that are in direct contact are a blue light-emitting layer and a green light-emitting layer.

7. The double-layer OLED display unit according to claim 5, characterized in that: The first light emitting unit and the second light emitting unit further include: Electron transport layer, electron blocking layer, hole transport layer, hole injection layer.

8. The double-layer OLED display unit according to claim 7, characterized in that: The first light-emitting unit includes a hole injection layer, a hole transport layer, an electron blocking layer, a red light-emitting layer, a first blocking layer, a blue light-emitting layer, a green light-emitting layer, and an electron transport layer, which are sequentially stacked in a direction away from the anode; The second light-emitting unit includes an electron transport layer, a red light-emitting layer, a second barrier layer, a green light-emitting layer, a blue light-emitting layer, an electron blocking layer, and a hole transport layer, which are sequentially stacked in a direction away from the cathode.

9. The double-layer OLED display unit according to any one of claims 1 to 8, characterized in that: The materials of all the light-emitting layers in the first light-emitting unit and the second light-emitting unit are fluorescent materials.

10. A display panel, characterized in that: The display panel comprises at least a plurality of double-layer OLED display units according to any one of claims 1 to 9.

11. An electronic device, characterized in that: The electronic device comprises at least the display panel according to claim 10.

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