Display panel and display device

Abstract

The application discloses a display panel and a display device, and belongs to the technical field of display. The display panel comprises an array substrate, a light-emitting layer arranged above the array substrate and comprising arrayed light-emitting units, and a light extraction layer arranged on the light-emitting side of the light-emitting layer and comprising a first organic encapsulating layer, a second organic encapsulating layer and arrayed light extraction units arranged between the first organic encapsulating layer and the second organic encapsulating layer. The light extraction units are arranged in alignment with the light-emitting units in the thickness direction of the display panel. The light extraction units are doped with nanoparticles, and the refractive index of the light extraction units is greater than the refractive index of the first organic encapsulating layer and the second organic encapsulating layer. The light extraction layer is configured to make the light emitted by the light-emitting units exit in a direction perpendicular to the light-emitting surface of the display panel. The display device comprises the display panel. The application significantly improves the forward light-emitting intensity and light-emitting quantity of the light-emitting units, improves the light-emitting efficiency and further reduces the power consumption of the display panel.

Description

Technical Field

[0001] This application relates to the field of display technology, and more particularly to a display panel with higher light intensity and light extraction efficiency, and a display device having the display panel. Background Technology

[0002] Organic light-emitting diodes (OLEDs) boast high luminous efficiency and fast response speed, enabling the fabrication of flexible OLED display panels on flexible substrates. Compared to liquid crystal display panels (LCDs), OLEDs offer advantages such as high contrast, wide color gamut, and no viewing angle degradation. Furthermore, they are bendable and can be used for flexible displays, making them popular among users. With technological advancements and improved living standards, OLED production technology is maturing, and market demands for higher power consumption are increasing. Light emission performance is thus becoming a key focus for users.

[0003] However, existing OLED display panels, lacking a light extraction structure, experience significant light attenuation after the light emitted by their light-emitting units (OLED light-emitting devices) passes through layers such as the Electroluminescence Layer (EL), Thin-film Encapsulation (TFE), Direct On-Cell Touch (DOT), and Modular Display Module (MOD). This results in low actual light extraction efficiency for the light-emitting units. To achieve the desired brightness, the required driving current for the light-emitting units must be greater, leading to higher power consumption for the display panel. This severely impacts the light extraction performance of the OLED display panel and increases power consumption.

[0004] To address the aforementioned technical problems, existing technologies urgently need improvement. Utility Model Content

[0005] This application provides a display panel and a display device to at least partially solve the above-mentioned technical problems.

[0006] To achieve the above objectives, according to a first aspect of this application, a display panel is provided, the display panel comprising: Array substrate; A light-emitting layer is disposed on the array substrate and includes an array of light-emitting units; A light extraction layer, disposed on the light-emitting side of the light-emitting layer, includes a first organic encapsulation layer, a second organic encapsulation layer located above the first organic encapsulation layer, and an array of light extraction units disposed between the first organic encapsulation layer and the second organic encapsulation layer; wherein... In the thickness direction of the display panel, the light extraction unit and the light emission unit are aligned and disposed; the light extraction unit is doped with nanoparticles, and the refractive index of the light extraction unit is greater than the refractive index of the first organic encapsulation layer and the second organic encapsulation layer; The light extraction layer is configured to cause the light emitted by the light-emitting unit to be emitted in a direction perpendicular to the light-emitting surface of the display panel.

[0007] Optionally, the refractive indexes of the first organic encapsulation layer and the second organic encapsulation layer are in the range of 1.2 to 1.5; And / or, the refractive index of the light extraction unit is in the range of 1.5 to 1.9.

[0008] Optionally, the light-emitting unit includes a first light-emitting unit that emits red light, a second light-emitting unit that emits green light, and a third light-emitting unit that emits blue light. The light extraction unit includes a first light extraction unit with a first refractive index disposed opposite to the first light-emitting unit, a second light extraction unit with a second refractive index disposed opposite to the second light-emitting unit, and a third light extraction unit with a third refractive index disposed opposite to the third light-emitting unit. Wherein, the first refractive index is greater than the second refractive index, and the second refractive index is greater than the third refractive index.

[0009] Optionally, the nanoparticles include first nanoparticles doped in the first light extraction unit, second nanoparticles doped in the second light extraction unit, and third nanoparticles doped in the third light extraction unit. The doping amount of the first nanoparticle is greater than that of the second nanoparticle, and the doping amount of the second nanoparticle is greater than that of the third nanoparticle.

[0010] Optionally, the particle size range of the nanoparticles doped in the light extraction unit is between 5 and 30 nm; The particle size of the first nanoparticle is larger than that of the second nanoparticle, and the particle size of the second nanoparticle is larger than that of the third nanoparticle.

[0011] Optionally, the light-emitting unit has a pixel opening facing the light extraction unit, and the orthographic projection of the light extraction unit on the array substrate at least covers the orthographic projection of the pixel opening on the array substrate.

[0012] Optionally, the light extraction unit has a light-incident surface near the pixel opening and a light-exit surface away from the pixel opening, wherein the light-exit surface includes at least one of an arc-shaped light-exit surface and a light-exit plane; The arc-shaped light-emitting surface protrudes from the side away from the light-incident surface.

[0013] Optionally, the first organic encapsulation layer has grooves arrayed on one side facing the second organic encapsulation layer, the grooves are recessed towards the pixel opening side, and the light extraction unit at least partially fills the grooves.

[0014] Optionally, the bottom surface dimension of the groove is smaller than the opening dimension of the groove, and the sidewalls of the groove extend obliquely and form an obtuse angle with the bottom surface.

[0015] Optionally, the display panel further includes: An inorganic encapsulation layer is disposed between the light-emitting layer and the first organic encapsulation layer; A cover plate is disposed on the side of the second organic encapsulation layer away from the first organic encapsulation layer.

[0016] According to a second aspect of this application, a display device is provided, the display device comprising the display panel described in any one of the preceding claims.

[0017] In the display panel of this application embodiment, by utilizing the above-described technical solution and the refractive index gradient design of the light extraction layer, as well as the efficient light extraction effect of the light extraction unit doped with nanoparticles, a converging effect is achieved on the light emitted from the lower light-emitting unit. This allows the lateral light emitted by the light-emitting unit to automatically converge in a direction perpendicular to the light-emitting surface of the display panel when refracted at the interface of the light extraction layer. Compared to existing technologies, this significantly improves the forward light emission intensity and quantity of the light-emitting unit, thereby increasing the light extraction efficiency. The higher forward light emission intensity and quantity also enable the array substrate to drive the light-emitting unit with lower voltage and smaller current to emit light at the same brightness, further reducing the power consumption of the display panel and meeting the market demand for low-power OLED display panel products.

[0018] Other features and advantages of this application will be described in detail in the following detailed description section. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] To gain a more complete understanding of this application and its beneficial effects, the following description will be provided in conjunction with the accompanying drawings, wherein the same reference numerals in the following description denote the same parts.

[0021] Figure 1 This is a top view of the display panel provided in an exemplary embodiment of this disclosure; Figure 2 This is an internal cross-sectional view of a display panel provided in an exemplary embodiment of this disclosure. Figure 1 ; Figure 3 This is an internal cross-sectional view of a display panel provided in an exemplary embodiment of this disclosure. Figure 2 .

[0022] Explanation of reference numerals in the attached figures: 100 - Display panel; 101 - Display area; 102 - Non-display area; 103 - Subpixel; 10-Array substrate; 11-Substrate; 12-Driving circuit layer; 20 - Emitting layer; 21 - Emitting unit; 211 - First emitting unit; 212 - Second emitting unit; 213 - Third emitting unit; 214 - Pixel aperture; 30 - Inorganic encapsulation layer; 40 - Light extraction layer; 41 - First organic encapsulation layer; 412 - Groove; 42 - Second organic encapsulation layer; 43 - Light extraction unit; 431 - First light extraction unit; 432 - Second light extraction unit; 433 - Third light extraction unit; 434 - Light incident surface; 435 - Arc-shaped light emitting surface; 436 - Light emitting plane; 437 - Light guide structure; 50 - Cover plate. Detailed Implementation

[0023] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the protection scope of this application.

[0024] To facilitate readers' understanding of the technical solution of this application, the length direction of the display panel 100 is defined as the X-axis direction, the width direction of the display panel 100 is defined as the Y-axis direction, and the thickness direction of the display panel 100 is defined as the Z-axis direction.

[0025] In existing OLED display panels, due to the lack of a light extraction structure, the light emitted by the light-emitting units undergoes significant attenuation after passing through layers such as the electroluminescent layer (EL), thin-film encapsulation layer (TFE), DOT, and MOD, resulting in low actual light extraction efficiency of the light-emitting units. To achieve the preset brightness, the driving current required by the light-emitting units must be larger, leading to higher power consumption of the display panel. This severely affects the light extraction performance of the OLED display panel and increases power consumption.

[0026] In view of this, please refer to Figure 1 According to a first aspect of this application, a display panel 100 is provided. The display panel 100 may be an OLED display panel. The display panel 100 has a display area 101 and a non-display area 102 surrounding the display area 101.

[0027] Specifically, please refer to Figures 2 to 3 The display panel 100 includes an array substrate 10, an emissive layer 20, and a light extraction layer 40. The array substrate 10 is the core substrate that drives and controls the operation of the emissive layer 20 and provides support for the emissive layer 20 and the light extraction layer 40.

[0028] The light-emitting layer 20 is disposed on the array substrate 10. The light-emitting layer 20 includes light-emitting units 21 arranged in an array in the display area 101. The light-emitting units 21 are electrically connected to the array substrate 10 so that the light-emitting units 21 can be lit or turned off under the control of the array substrate 10.

[0029] The light extraction layer 40 is disposed on the light-emitting side of the light-emitting layer 20. In this embodiment, the light-emitting side of the light-emitting layer 20 is described as the side away from the array substrate 10, i.e., above the light-emitting layer 20. Along the thickness direction of the display panel 100 (in this embodiment, the Z-axis direction is used as an example, and will not be described again below), the light extraction layer 40 includes a first organic encapsulation layer 41, a second organic encapsulation layer 42 located above the first organic encapsulation layer 41, and light extraction units 43 arranged in an array between the first organic encapsulation layer 41 and the second organic encapsulation layer 42.

[0030] In the thickness direction of the display panel 100, the light extraction unit 43 and the light emission unit 21 are aligned. Here, alignment means that the light extraction unit 43 and the light emission unit 21 are directly opposite each other, and their orthogonal projections on the surface of the array substrate 10 overlap. This can be achieved through precise overlay of the patterning process. The alignment error is controlled at the micrometer level, ensuring that the light extraction unit 43 and the light emission unit 21 below are precisely aligned in the thickness direction of the display panel 100.

[0031] The light extraction unit 43 is doped with nanoparticles, and the refractive index of the light extraction unit 43 is greater than that of the first organic encapsulation layer 41 and the second organic encapsulation layer 42. Preferably, the refractive indices of the first organic encapsulation layer 41 and the second organic encapsulation layer 42 are kept consistent, so that the refractive index of the light extraction unit 43 in the middle position is greater than that of the organic encapsulation layers on the upper and lower sides.

[0032] Nanoparticles are doped particles with particle sizes in the nanoscale range. The shape of the nanoparticles doped in the light extraction unit 43 is not limited to dense particles or non-particles. They can also be particles or non-particles with specific structures (such as hollow, porous, etc.). Furthermore, the doped nanoparticles can be surface-treated or not. This application does not make any specific limitations in this regard.

[0033] Specifically, nanoparticles can be made from one or more of the following materials, including but not limited to organic materials, metallic materials, inorganic non-metallic materials, and composite materials. For the same structure, nanoparticles made of different materials have different intrinsic refractive indices. For example, the intrinsic refractive index of titanium dioxide (TiO2) nanoparticles is between 2.4 and 2.7, that of zirconium dioxide (ZrO2) nanoparticles is between 2.1 and 2.2, that of hafnium dioxide (HfO2) nanoparticles is between 2.05 and 2.15, that of zinc oxide (ZnO) nanoparticles is between 2.0 and 2.1, that of silver (Ag) nanoparticles is around 2.0, that of gold (Au) nanoparticles is between 1.8 and 2.0, and that of silicon nitride (SiN2) nanoparticles. xThe intrinsic refractive index of the nanoparticles is approximately 1.9, while that of alumina (Al₂O₃) nanoparticles is between 1.6 and 1.7. For the same material, nanoparticles with different structures have different intrinsic refractive indices. For example, the intrinsic refractive index of dense silica (SiO₂) nanoparticles is between 1.45 and 1.47, that of porous silica (SiO₂) nanoparticles is between 1.23 and 1.35, and that of hollow silica (SiO₂) nanoparticles is between 1.17 and 1.40. By doping the light extraction unit 43 with suitable nanoparticles, the refractive index of the light extraction unit 43 can be precisely controlled, thereby changing the layer structure interface with different refractive indices and improving the light extraction efficiency.

[0034] The light extraction layer 40 is configured to cause the light emitted by the light-emitting unit 21 to be emitted in a direction perpendicular to the light-emitting surface of the display panel 100.

[0035] Through the above technical solution, the display panel 100 provided in this application has light extraction units 43, doped with nanoparticles and with a relatively higher refractive index, arrayed between the first organic encapsulation layer 41 and the second organic encapsulation layer 42. A multi-layer light extraction layer 40 with a refractive index gradient of "low-high-low" is constructed above the light-emitting unit 21. Utilizing the refractive index gradient design of the light extraction layer 40 and the efficient light extraction effect of the nanoparticle-doped light extraction units, a converging effect is achieved on the light emitted from the lower light-emitting unit 21. This allows the lateral light emitted by the light-emitting unit 21 to automatically converge in a direction perpendicular to the light-emitting surface of the display panel 100 when refracted at the interface of the light extraction layer 40. Compared with existing technologies, this significantly improves the forward light emission intensity and quantity of the light-emitting unit 21, thereby increasing the light extraction efficiency. The higher forward light emission intensity and quantity also allow the array substrate 10 to drive the light-emitting unit 21 with lower voltage and smaller current to emit light at the same brightness, further reducing the power consumption of the display panel 100 and meeting the market demand for low-power OLED display panel 100 products.

[0036] In some embodiments, please refer to Figures 2 to 3 In the display panel 100 provided in this application, the array substrate 10 includes a substrate 11 and a driving circuit layer 12 disposed on the substrate 11. The substrate 11 can be made of a rigid material such as glass or a flexible material such as polyimide (PI). This application does not make specific limitations on this.

[0037] Specifically, the driving circuit layer 12 includes thin-film transistors arrayed within the display area 101 for driving the light-emitting unit 21 to illuminate. The light-emitting unit 21 and the thin-film transistors are arranged vertically opposite each other in the thickness direction of the display panel 100. The term "opposite arrangement" does not require that the light-emitting unit 21 and the thin-film transistors be completely directly opposite each other in the thickness direction of the display panel 100; they can be partially opposite or misaligned, and this application does not impose specific limitations on this.

[0038] The light-emitting unit 21 is electrically connected to the corresponding thin-film transistor, so that the light-emitting unit 21 can be lit or turned off under the drive of the corresponding thin-film transistor. The light-emitting unit 21 and the corresponding thin-film transistor constitute the sub-pixel 103 of the display panel 100 (e.g., ...). Figure 1 (as shown in the diagram) Main functional structure.

[0039] Those skilled in the art will understand that the number of thin-film transistors corresponding to each light-emitting unit 21 can be one or more. The active layer material of the thin-film transistor includes polycrystalline silicon semiconductor, specifically low-temperature polycrystalline silicon semiconductor (LTPS) or oxide semiconductor, wherein the oxide semiconductor can be indium gallium zinc oxide (IGZO). For the OLED display panel 100, the thin-film transistors corresponding to each light-emitting unit 21 preferably include low-temperature polycrystalline silicon thin-film transistors (LTPS TFTs) and oxide thin-film transistors (Oxide TFTs). The low-temperature polycrystalline silicon thin-film transistor (LTPS TFT) is used as a switching transistor, and the oxide thin-film transistor (Oxide TFT) is used as a driving transistor. The two work together to form a low-temperature polycrystalline oxide (LTPO) thin-film transistor, which gives the display panel 100 the advantages of both strong driving capability and low power consumption, further improving the display effect of the display panel 100 and reducing the power consumption of the display panel 100.

[0040] In some embodiments, in the display panel 100 provided in this application, the refractive index range of the first organic encapsulation layer 41 and the second organic encapsulation layer 42 is between 1.2 and 1.5. This range may or may not include the endpoints 1.2 and 1.5, and this application does not specifically limit this. Preferably, the first organic encapsulation layer 41 and the second organic encapsulation layer 42 have the same refractive index, which can be achieved by using the same material in specific implementations. For example, the material of the first organic encapsulation layer 41 and the second organic encapsulation layer 42 can be a photocurable resin system with high light transmittance (e.g., acrylate resin, epoxy / siloxane modified resin, etc.), which can balance process efficiency and flexible adaptation. In addition, other auxiliary materials can also be added to the material of the first organic encapsulation layer 41 and the second organic encapsulation layer 42 to improve the weather resistance of the organic encapsulation layer and adjust the refractive index. In specific implementation, the refractive index of the first organic encapsulation layer 41 and the second organic encapsulation layer 42 can be set to, for example, 1.2, 1.22, 1.25, 1.28, 1.32, 1.35, 1.38, 1.41, 1.43, 1.45, 1.47, 1.49, 1.50, etc.

[0041] Correspondingly, the refractive index of the light extraction unit 43 is greater than that of the first organic encapsulation layer 41 and the second organic encapsulation layer 42. Specifically, the refractive index of the light extraction unit 43 is in the range of 1.5 to 1.9. This refractive index range may include the endpoint values ​​of 1.5 and 1.9, or it may not include the endpoint values ​​of 1.5 and 1.9. This application does not make a specific limitation in this regard. In specific implementation, it can be adjusted accordingly based on the refractive index of the first organic encapsulation layer 41 and the second organic encapsulation layer 42 to ensure that the refractive index of the light extraction unit 43 is greater than that of the first organic encapsulation layer 41 and the second organic encapsulation layer 42.

[0042] The material of the light extraction unit 43 needs to meet the requirements of high refractive index and high transmittance, and be compatible with the organic encapsulation layer. Understandably, the main material of the light extraction unit 43 can be the same as or different from the materials of the first organic encapsulation layer 41 and the second organic encapsulation layer 42; this application does not specifically limit this. In specific implementations, the refractive index of the light extraction unit 43 can be precisely controlled between 1.5 and 1.9 by doping the material of the light extraction unit 43 with nanoparticles having a relatively higher intrinsic refractive index, or by simultaneously doping it with other organic or inorganic hybrid materials. Specifically, the refractive index of the light extraction unit 43 can be set to values ​​such as 1.5, 1.53, 1.58, 1.60, 1.64, 1.67, 1.7, 1.73, 1.75, 1.82, 1.85, 1.87, 1.88, and 1.9.

[0043] Through the above technical solution, the display panel 100 provided in this application embodiment controls the refractive index of the first organic encapsulation layer 41 and the second organic encapsulation layer 42 to be between 1.2 and 1.5, and controls the refractive index of the light extraction unit 43 to be between 1.5 and 1.9. At the same time, the refractive index of the light extraction unit 43 is limited to be greater than the refractive index of the first organic encapsulation layer 41 and the second organic encapsulation layer 42, realizing the gradient change requirement of the refractive index of the light extraction layer 40 from "low-high-low", satisfying the modulation requirement of the light extraction layer 40 for the lateral light emission of the light-emitting unit 21 to be positively deflected, and ensuring the light-gathering effect of the light extraction unit 43.

[0044] In a specific implementation, a first organic encapsulation layer 41 can be fabricated on the side of the light-emitting layer 20 away from the array substrate 10 using a coating process. After the first organic encapsulation layer 41 is cured and planarized, patterned light extraction units 43 can be fabricated on the surface of the first organic encapsulation layer 41 away from the light-emitting layer 20 using processes such as inkjet printing, transfer printing, or vacuum deposition, ensuring that the light extraction units 43 are precisely aligned with the light-emitting units 21 in the lower light-emitting layer 20. After the light-emitting units 21 are cured, a second organic encapsulation layer 42 can be fabricated on the side of the first organic encapsulation layer 41 away from the light-emitting layer 20 using a coating process, ensuring that the second organic encapsulation layer 42 completely covers the light extraction units 43.

[0045] Furthermore, in the display panel 100 provided in this application embodiment, the refractive index of the first organic encapsulation layer 41 and the second organic encapsulation layer 42 is preferably controlled between 1.4 and 1.5, and the refractive index of the light extraction unit 43 is preferably controlled between 1.5 and 1.9, and the refractive index of the light extraction unit 43 is greater than the refractive index of the first organic encapsulation layer 41 and the second organic encapsulation layer 42. In specific implementation, the refractive index of the first organic encapsulation layer 41 and the second organic encapsulation layer 42 can be set to, for example, 1.4, 1.42, 1.42, 1.45, 1.48, 1.49, etc., and the refractive index of the light extraction unit 43 can be set to, for example, 1.5, 1.52, 1.55, 1.58, 1.6, 1.65, 1.68, 1.72, 1.76, 1.78, 1.83, 1.86, 1.9, etc.

[0046] According to Fresnel's formula, the smaller the difference in refractive index between adjacent media, the lower the reflection loss of light at the interface. This application controls the refractive indices of the first organic encapsulation layer 41 and the second organic encapsulation layer 42 to be between 1.4 and 1.5, and the refractive index of the light extraction unit 43 to be between 1.5 and 1.9. Furthermore, the refractive index of the light extraction unit 43 is greater than that of the first organic encapsulation layer 41 and the second organic encapsulation layer 42. This allows the refractive indices of the organic encapsulation layers on the upper and lower sides of the light extraction layer 40 to approach the lower limit of 1.5 of the refractive index of the light extraction unit 43 in the middle position. This controls the reflectivity of the interface between the "first organic encapsulation layer 41 - light extraction unit 43" and the "light extraction unit 43 - second organic encapsulation layer 42" to below 2%, avoiding repeated reflections of light between the layers of the light extraction layer 40 due to excessive refractive index differences, further reducing light loss and increasing the amount of light emitted.

[0047] In some embodiments, please refer to Figures 2 to 3 In the display panel 100 provided in this application, the light-emitting unit 21 includes a first light-emitting unit 211 that emits red light, a second light-emitting unit 212 that emits green light, and a third light-emitting unit 213 that emits blue light. Each of the first light-emitting unit 211, the second light-emitting unit 212, and the third light-emitting unit 213 constitutes a sub-pixel 103 light-emitting structure that emits different colors of light in an RGB pixel. Along the length direction of the display panel 100 (taking the X-axis direction as an example in this embodiment, which will not be described in detail below) and the width direction of the display panel 100 (taking the Y-axis direction as an example in this embodiment, which will not be described in detail below), there are multiple arrangements of RGB pixels. For the LCD display panel 100, a standard RGB arrangement can be adopted, that is, the sub-pixels 103 are arranged horizontally in the order of "RGBRGB", and each RGB pixel is composed of a group of adjacent R, G, B sub-pixels 103. For the OLED display panel 100, arrangements such as diamond (Pen Tile), triangle (Delta), and pearl (Pearl) can be adopted, and this application does not limit this.

[0048] Correspondingly, the light extraction unit 43 includes a first light extraction unit 431 with a first refractive index disposed opposite to the first light-emitting unit 211, a second light extraction unit 432 with a second refractive index disposed opposite to the second light-emitting unit 212, and a third light extraction unit 433 with a third refractive index disposed opposite to the third light-emitting unit 213. The first refractive index is greater than the second refractive index, and the second refractive index is greater than the third refractive index; that is, the refractive index of the first light extraction unit 431 > the refractive index of the second light extraction unit 432 > the refractive index of the third light extraction unit 433.

[0049] The emission wavelength of different colored sub-pixels 103 determines their natural refractive index. Among them, red light has the longest wavelength (620~750nm) and the lowest refractive index in the medium; green light has a medium wavelength (495~570nm) and a moderate refractive index in the medium; and blue light has the shortest wavelength (450~495nm) and the highest refractive index in the medium. If light extraction units 43 with the same refractive index are used, the three colors of light will propagate in different directions after refraction, resulting in dispersion of forward light output and increased side leakage loss.

[0050] In view of this, this application sets the first refractive index of the first light extraction unit 431 (corresponding to the first light-emitting unit 211 emitting red light) to be greater than the second refractive index of the second light extraction unit 432 (corresponding to the second light-emitting unit 212 emitting green light). The third refractive index of the third light extraction unit 433 (corresponding to the third light-emitting unit 213 that emits blue light) creates a refractive index gradient between the light extraction units 43 corresponding to different color sub-pixels 103, thereby offsetting the natural refractive index differences of different colors of light. This results in the first light-emitting unit 211 emitting red light (low natural refractive index) being paired with the first light extraction unit 431 with a high refractive index, the second light-emitting unit 212 emitting green light (medium natural refractive index) being paired with the second light extraction unit 432 with a medium refractive index, and the third light-emitting unit 213 emitting blue light (high natural refractive index) being paired with the third light extraction unit 433 with a low refractive index. This ensures that the three colors of light emitted by the RGB pixels, after being refracted by their respective light extraction units 43, can all converge vertically and positively towards the light-emitting surface of the display panel 100. This ensures that the light emission direction of different colors of light is consistent, guarantees the positive light emission intensity and light emission amount of the display panel 100, improves the overall brightness uniformity of the display panel 100, and avoids the problem of uneven color mixing caused by inconsistent light emission directions of different colors of light, further improving the display effect of the display panel 100.

[0051] Furthermore, the first refractive index of the first light extraction unit 431 can be controlled between 1.75 and 1.9. This refractive index range may include the endpoints 1.75 and 1.9, or may not include the endpoints 1.75 and 1.9. In specific implementation, this can be achieved through one or more of the following methods: doping with nanoparticles of high refractive index, or increasing the doping amount of nanoparticles. The second refractive index of the second light extraction unit 432 can be controlled between 1.6 and 1.75. This refractive index range may include the endpoints 1.6 and 1.75, or may not include the endpoints 1.6 and 1.75. In specific implementation, this can be achieved through one or more of the following methods: doping with nanoparticles of medium refractive index, or evenly controlling the doping amount of nanoparticles. The third refractive index of the third light extraction unit 433 can be controlled between 1.5 and 1.6. This refractive index range may include the endpoints 1.5 and 1.6, or may not include the endpoints 1.5 and 1.6. In specific implementation, this can be achieved through one or more of the following methods: doping with nanoparticles of low refractive index, or reducing the doping amount of nanoparticles. In specific implementation, it is sufficient to ensure that the first refractive index of the first light extraction unit 431 is greater than the second refractive index of the second light extraction unit 432, and the second refractive index of the second light extraction unit 432 is greater than the third refractive index of the third light extraction unit 433.

[0052] For example, in specific implementation, the first refractive index of the first light extraction unit 431 can be set to, for example, 1.75, 1.78, 1.8, 1.82, 1.85, 1.88, 1.9, etc.; the second refractive index of the second light extraction unit 432 can be set to, for example, 1.6, 1.62, 1.65, 1.68, 1.70, 1.72, 1.74, etc.; and the third refractive index of the third light extraction unit 433 can be set to, for example, 1.5, 1.52, 1.55, 1.57, 1.59, etc.

[0053] In one embodiment, the display panel 100 provided in this application includes nanoparticles doped in a first light extraction unit 431, second nanoparticles doped in a second light extraction unit 432, and third nanoparticles doped in a third light extraction unit 433. The doping amount of the first nanoparticles is greater than that of the second nanoparticles, and the doping amount of the second nanoparticles is greater than that of the third nanoparticles. Here, "doping amount" is defined as a percentage by mass.

[0054] Specifically, the materials and structures of the first, second, and third nanoparticles can be the same or different, and this application does not impose specific limitations in this regard. In specific implementation, the refractive index of the corresponding light extraction unit 43 can be precisely controlled by the difference in the doping amount of the nanoparticles. Setting the doping amount of the first nanoparticle to be greater than that of the second nanoparticle, and setting the doping amount of the second nanoparticle to be greater than that of the third nanoparticle, can ensure that the first refractive index of the doped first light extraction unit 431 is greater than the second refractive index of the doped second light extraction unit 432, and the second refractive index of the doped second light extraction unit 432 is greater than the third refractive index of the doped third light extraction unit 433.

[0055] Through the above technical solution, the display panel 100 provided in this embodiment achieves differentiated refractive index regulation of different light extraction units 43 by controlling the doping amount of the first nanoparticle, the second nanoparticle, and the third nanoparticle. This ensures that a refractive index gradient can be formed between the light extraction units 43 corresponding to different color light-emitting units 21, adapting to the natural refractive index differences of different colors of light. This ensures that the three colors of light emitted by the RGB pixels, after being refracted by their respective light extraction units 43, can all converge vertically and positively towards the light-emitting surface of the display panel 100, ensuring that the light emission direction of different colors of light is consistent. This guarantees the positive light emission intensity and light emission amount of the display panel 100, improves the overall brightness uniformity of the display panel 100, and avoids the problem of uneven color mixing caused by inconsistent light emission directions of different colors of light, further improving the display effect of the display panel 100. In addition, the doped nanoparticles can effectively suppress the reflection, scattering, and absorption loss of light in the light extraction unit 43, significantly reducing the loss of light propagation in the light extraction layer 40, and further improving the light emission efficiency.

[0056] In specific implementation, the doping amount of the first nanoparticle in the first light extraction unit 431 can be controlled between 30% and 40%. Specifically, the doping amount of the first nanoparticle in the first light extraction unit 431 can be set to 30%, 32%, 34%, 35%, 37%, 39%, 40%, etc. The doping amount of the second nanoparticle in the second light extraction unit 432 can be controlled between 15% and 25%. Specifically, the doping amount of the third nanoparticle in the third light extraction unit 433 can be controlled between 5% and 15%.

[0057] In some embodiments, the first nanoparticle, the second nanoparticle, and the third nanoparticle can be a single type of nanoparticle or a mixture of multiple nanoparticles. For example, the first nanoparticle can be TiO2 nanoparticles, ZrO2 nanoparticles, HfO2 nanoparticles, ZnO nanoparticles, Ag nanoparticles, Au nanoparticles, or SiN nanoparticles. xNanoparticles, Al2O3 nanoparticles, dense SiO2 nanoparticles, porous SiO2 nanoparticles, and hollow SiO2 nanoparticles; or, the first nanoparticle may also be TiO2 nanoparticles, ZrO2 nanoparticles, HfO2 nanoparticles, ZnO nanoparticles, Ag nanoparticles, Au nanoparticles, or SiN nanoparticles. x A mixture of at least two types of nanoparticles, including nanoparticles, Al2O3 nanoparticles, dense SiO2 nanoparticles, porous SiO2 nanoparticles, and hollow SiO2 nanoparticles.

[0058] Similarly, the second nanoparticle can be TiO2 nanoparticles, ZrO2 nanoparticles, HfO2 nanoparticles, ZnO nanoparticles, Ag nanoparticles, Au nanoparticles, or SiN nanoparticles. x The second nanoparticle can be one of the following: Al2O3 nanoparticles, dense SiO2 nanoparticles, porous SiO2 nanoparticles, or hollow SiO2 nanoparticles; or, the second nanoparticle can also be TiO2 nanoparticles, ZrO2 nanoparticles, HfO2 nanoparticles, ZnO nanoparticles, Ag nanoparticles, Au nanoparticles, or SiN. x A mixture of at least two types of nanoparticles, including nanoparticles, Al2O3 nanoparticles, dense SiO2 nanoparticles, porous SiO2 nanoparticles, and hollow SiO2 nanoparticles.

[0059] Similarly, the third nanoparticle can be TiO2 nanoparticles, ZrO2 nanoparticles, HfO2 nanoparticles, ZnO nanoparticles, Ag nanoparticles, Au nanoparticles, or SiN nanoparticles. x The third nanoparticle can be one of the following: Al2O3 nanoparticles, dense SiO2 nanoparticles, porous SiO2 nanoparticles, or hollow SiO2 nanoparticles; or, the third nanoparticle can also be TiO2 nanoparticles, ZrO2 nanoparticles, HfO2 nanoparticles, ZnO nanoparticles, Ag nanoparticles, Au nanoparticles, or SiN. x A mixture of at least two types of nanoparticles, including nanoparticles, Al2O3 nanoparticles, dense SiO2 nanoparticles, porous SiO2 nanoparticles, and hollow SiO2 nanoparticles.

[0060] In practice, the refractive index of the light extraction unit 43 can be controlled by adjusting the amount of different nanoparticles doped, or by doping with appropriate types of nanoparticles to help control the refractive index of the light extraction unit 43.

[0061] Furthermore, in addition to doping nanoparticles, the light extraction unit 43 can also be selectively doped with other organic or inorganic hybrid materials (such as metal oxanes). By adding hybrid materials, the refractive index control precision of the light extraction unit 43 can be further improved, preventing nanoparticles from agglomerating or peeling off from the substrate of the light extraction unit 43, and further reducing light scattering loss.

[0062] In some embodiments, the particle size range of the nanoparticles doped in the light extraction unit 43 of the display panel 100 provided in this application can be controlled between 5 and 30 nm. Specifically, the particle size of the first nanoparticle is larger than that of the second nanoparticle, and the particle size of the second nanoparticle is larger than that of the third nanoparticle.

[0063] Specifically, the particle size range of the first nanoparticle can be controlled between 20 and 30 nm, and this particle size range may or may not include the endpoint values ​​of 20 and 30; the particle size range of the second nanoparticle can be controlled between 15 and 25 nm, and this particle size range may or may not include the endpoint values ​​of 15 and 25; the particle size range of the third nanoparticle can be controlled between 5 and 20 nm, and this particle size range may or may not include the endpoint values ​​of 5 and 20. The particle sizes of all nanoparticles doped in each light extraction unit 43 may be exactly the same or not exactly the same, and this application does not make specific limitations in this regard.

[0064] For example, in specific implementation, the particle size of the first nanoparticle can be set to, for example, 20nm, 22nm, 24nm, 26nm, 28nm, 30nm, etc.; the particle size of the second nanoparticle can be set to, for example, 15nm, 18nm, 20nm, 22nm, 24nm, 25nm, etc.; and the particle size of the third nanoparticle can be set to, for example, 5nm, 8nm, 10nm, 12nm, 14nm, 15nm, 17nm, 19nm, 20nm, etc.

[0065] Through the above technical solution, the display panel 100 provided in this application embodiment can indirectly control the dispersion of nanoparticles in the light extraction unit 43 by controlling the particle size of the nanoparticles doped in the light extraction unit 43, thereby avoiding light propagation loss caused by nanoparticle aggregation and further improving the light output intensity and light output of the light extraction unit 43.

[0066] In some embodiments, please refer to Figures 2 to 3The display panel 100 provided in this application has pixel openings 214 facing the light extraction unit 43 of the upper light extraction unit 21. The orthographic projection of the light extraction unit 43 on the array substrate 10 at least covers the orthographic projection of the pixel opening 214 on the array substrate 10, so as to ensure that the light extraction unit 43 can completely block the pixel opening 214 below, so that the light extraction unit 43 can maximize the acquisition of the light emitted by the light extraction unit 21 below, significantly reducing the escape loss of lateral light at the edge of the pixel opening 214 and improving the light utilization rate.

[0067] Furthermore, the orthographic projection of the light extraction unit 43 on the array substrate 10 is larger than the orthographic projection of the pixel opening 214 on the array substrate 10, causing at least part of the edge structure of the light extraction unit 43 to extend beyond the edge of the pixel opening 214. This design provides redundant space for the alignment of the light extraction unit 43 with the lower light-emitting unit 21, ensuring that the light extraction unit 43 completely covers the pixel opening 214, avoiding the problem of partial functional failure of the light extraction unit 43 caused by alignment deviation, ensuring the light intensity and light output of the light extraction layer 40, and ensuring the display effect of the display panel 100.

[0068] In some embodiments, please refer to Figures 2 to 3 , Figure 2 and Figure 3 Two different embodiments of the display panel of this application are disclosed by way of example. The difference between the two lies in the structure of the light extraction unit 43. The other similar parts will not be described again below. In the display panel 100 provided by this application, in the thickness direction of the display panel 100, that is, the Z-axis direction, the light extraction unit 43 has a light-incident surface 434 close to the pixel opening 214 and a light-exiting surface away from the pixel opening 214. The light-exiting surface includes an arc-shaped light-exiting surface 435 (e.g., Figure 2 As shown), light-emitting plane 436 (as shown) Figure 3 At least one of the following (as shown in the figure).

[0069] Please refer to Figure 2 The arc-shaped light-emitting surface 435 protrudes away from the light-incident surface 434, making the light extraction unit 43 form a microlens structure similar to a convex lens. This structure allows the light extraction unit 43 to utilize the secondary focusing effect of its arc-shaped light-emitting surface 435 to further deflect light in the forward direction, significantly improving the forward focusing effect and light utilization rate of the light extraction unit 43, and further increasing the forward light emission intensity and amount of the light extraction layer 40. In addition, the arc-shaped light-emitting surface 435 reduces diffuse reflection of light at the light-emitting interface, effectively "pulling back" the divergent light from the edge of the light-emitting unit 21 to the forward direction. Compared to the design using a light-emitting plane 436, this avoids light loss caused by light scattering at the edge of the light-emitting surface.

[0070] In some embodiments, please refer to Figure 3 The light extraction unit 43, designed with a light-emitting plane 436, is superior to... Figure 2 The use of an arc-shaped light-emitting surface 435 simplifies the manufacturing process, significantly reducing the manufacturing cost of the light extraction layer 40 and making it suitable for mass production. Furthermore, the uniform light emission across the light-emitting surface 436 avoids the problem of high light emission in the central area and low light emission at the edges that can occur with arc-shaped light-emitting surfaces 435. This ensures uniform light emission from the light extraction unit 43, improves the uniformity of brightness of the sub-pixels 103 of the display panel 100, and enhances the display effect.

[0071] Further, please refer to Figure 3 The display panel 100 provided in this application has grooves 412 arrayed on the side of the first organic encapsulation layer 41 facing the second organic encapsulation layer 42. The grooves 412 are recessed towards the pixel opening 214, and the light extraction unit 43 at least partially fills the grooves 412. In specific implementation, the grooves 412 can be patterned on the surface of the first organic encapsulation layer 41 using a photolithography process.

[0072] Through the above technical solution, the display panel 100 provided in this embodiment of the application, by setting a groove 412 on the surface of the first organic encapsulation layer 41, makes the groove 412 precisely aligned with the pixel opening 214 below, which plays the role of a positioning template. There is no need to set additional positioning marks for the light extraction unit 43, which can shorten the process steps, facilitate the subsequent preparation of the light extraction unit 43, and ensure the precise alignment of the light extraction unit 43 with the light-emitting unit 21 below.

[0073] Meanwhile, the groove 412 can restrict the flow of the material of the light extraction unit 43, prevent the material of the light extraction unit 43 from spreading to the surroundings before curing, and ensure that the structure of the light extraction unit 43 after curing meets the design standards.

[0074] In addition, at least a portion of the structure of the light extraction unit 43 is located within the groove 412, forming a tenon-like interlocking structure between the light extraction unit 43 and the first organic encapsulation layer 41. Compared to planar bonding, this significantly increases the contact area between the light extraction unit 43 and the first organic encapsulation layer 41, thereby improving the bonding strength between them. This avoids interlayer peeling problems caused by thermal expansion and contraction, vibration, and other factors during long-term use, and improves the reliability and service life of the light extraction layer 40.

[0075] In some embodiments, please refer to Figure 3The display panel 100 provided in this application has a bottom surface dimension of the groove 412 that is smaller than the opening dimension of the groove 412. The sidewall of the groove 412 extends obliquely and forms an obtuse angle with the bottom surface. This design causes the portion of the light extraction unit 43 embedded in the groove 412 to form an approximately inverted trapezoidal light guide structure 437. The sidewall surface of the light guide structure 437 that is in contact with the sidewall of the groove 412 has a lateral divergence angle with the light emitted by the light-emitting unit 21. This causes the light that might originally deviate from the edge of the light extraction unit 43 to be reflected or refracted by the sidewall surface of the light guide structure 437 and guided into the interior of the light extraction unit 43, avoiding lateral light loss of the light-emitting unit 21 and further improving the light utilization rate of the light extraction unit 43.

[0076] Furthermore, the orthographic projection of the bottom surface of the groove 412 onto the array substrate 10 at least covers the orthographic projection of the pixel opening 214 onto the array substrate 10, ensuring that the bottom surface of the groove 412 completely blocks the pixel opening 214 from above. This allows the sidewall of the light guide structure 437 to function in the peripheral area of ​​the pixel opening 214, thereby guiding all the lateral light emitted from the edge of the pixel opening 214 into the light extraction unit 43. This further reduces the escape loss of the lateral light emitted from the edge of the pixel opening 214 and improves the light utilization rate of the light extraction unit 43.

[0077] In some embodiments, please refer to Figures 2 to 3 The display panel 100 provided in this application further includes an inorganic encapsulation layer 30 and a cover plate 50. The inorganic encapsulation layer 30 is disposed between the light-emitting layer 20 and the first organic encapsulation layer 41, and the cover plate 50 is disposed on the side of the second organic encapsulation layer 42 away from the first organic encapsulation layer 41. The inorganic encapsulation layer 30 isolates the light extraction layer 40 from the light-emitting layer 20, forming an isolation and protection function for the light-emitting layer 20, preventing external moisture, oxygen, etc., from intruding into the light-emitting layer 20, and preventing corrosion or oxidation of the light-emitting unit 21 due to water or oxygen intrusion.

[0078] Specifically, the inorganic encapsulation layer 30, serving as an intermediate medium between the light-emitting layer 20 and the light extraction layer 40, can have its refractive index set to be close to that of the first organic encapsulation layer 41. This reduces the refractive index difference between the inorganic encapsulation layer 30 and the first organic encapsulation layer 41, enabling the inorganic encapsulation layer 30 to function as an optical adapter. This further reduces interfacial reflection loss of light, allowing the upper light extraction unit 43 to maximize the acquisition of the emitted light from the light-emitting unit 21 and improve light utilization. Furthermore, the inorganic encapsulation layer 30 provides structural support for the upper light extraction layer 40 and can undergo planarization to improve surface smoothness, providing a uniform substrate for the subsequent fabrication of the first organic encapsulation layer 41.

[0079] The cover plate 50 is the outer protective structure of the display panel 100, and can be designed as a single layer or a multi-layer structure. The cover plate 50 must meet the design requirements for structural strength and surface hardness, preventing the intrusion of external moisture, oxygen, etc., while also preventing the surface of the display panel 100 from being scratched or bumped.

[0080] According to a second aspect of this disclosure, a display device is provided, which includes the display panel 100 described in any of the above embodiments. This display device possesses all the beneficial effects of the aforementioned display panel 100, which will not be elaborated upon herein.

[0081] For example, the display device may be a mobile phone, tablet, monitor, television, outdoor screen, electronic billboard, etc., as well as wearable display devices such as smartwatches and virtual reality (VR) devices. This application does not specifically limit the types of devices.

[0082] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0083] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0084] The embodiments, implementation methods, and related technical features of this application can be combined and substituted for each other without conflict.

[0085] The above are merely preferred embodiments of this application and are not intended to limit this application in any way. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of this application without departing from the technical solution of this application shall still fall within the scope of the technical solution of this application.

Claims

1. A display panel, characterized in that, include: Array substrate; A light-emitting layer is disposed on the array substrate and includes an array of light-emitting units; A light extraction layer, disposed on the light-emitting side of the light-emitting layer, includes a first organic encapsulation layer, a second organic encapsulation layer located above the first organic encapsulation layer, and an array of light extraction units disposed between the first organic encapsulation layer and the second organic encapsulation layer; wherein... In the thickness direction of the display panel, the light extraction unit and the light emission unit are aligned and disposed; the light extraction unit is doped with nanoparticles, and the refractive index of the light extraction unit is greater than the refractive index of the first organic encapsulation layer and the second organic encapsulation layer; The light extraction layer is configured to cause the light emitted by the light-emitting unit to be emitted in a direction perpendicular to the light-emitting surface of the display panel.

2. The display panel according to claim 1, characterized in that, The refractive indices of the first organic encapsulation layer and the second organic encapsulation layer are in the range of 1.2 to 1.5; And / or, the refractive index of the light extraction unit is in the range of 1.5 to 1.

9.

3. The display panel according to claim 2, characterized in that, The light-emitting unit includes a first light-emitting unit that emits red light, a second light-emitting unit that emits green light, and a third light-emitting unit that emits blue light. The light extraction unit includes a first light extraction unit with a first refractive index disposed opposite to the first light-emitting unit, a second light extraction unit with a second refractive index disposed opposite to the second light-emitting unit, and a third light extraction unit with a third refractive index disposed opposite to the third light-emitting unit. Wherein, the first refractive index is greater than the second refractive index, and the second refractive index is greater than the third refractive index.

4. The display panel according to claim 3, characterized in that, The nanoparticles include first nanoparticles doped in the first light extraction unit, second nanoparticles doped in the second light extraction unit, and third nanoparticles doped in the third light extraction unit. The doping amount of the first nanoparticle is greater than that of the second nanoparticle, and the doping amount of the second nanoparticle is greater than that of the third nanoparticle.

5. The display panel according to claim 4, characterized in that, The particle size range of the nanoparticles doped in the light extraction unit is between 5 and 30 nm. The particle size of the first nanoparticle is larger than that of the second nanoparticle, and the particle size of the second nanoparticle is larger than that of the third nanoparticle.

6. The display panel according to claim 1, characterized in that, The light-emitting unit has a pixel opening facing the light extraction unit, and the orthographic projection of the light extraction unit on the array substrate at least covers the orthographic projection of the pixel opening on the array substrate.

7. The display panel according to claim 6, characterized in that, The light extraction unit has a light-incident surface close to the pixel opening and a light-outceasing surface away from the pixel opening. The light-outceasing surface includes at least one of an arc-shaped light-outceasing surface and a light-outceasing plane. The arc-shaped light-emitting surface protrudes from the side away from the light-incident surface.

8. The display panel according to claim 6, characterized in that, The first organic encapsulation layer has grooves arrayed on one side facing the second organic encapsulation layer, the grooves are recessed towards the pixel opening side, and the light extraction unit at least partially fills the grooves.

9. The display panel according to claim 8, characterized in that, The bottom surface dimension of the groove is smaller than the opening dimension of the groove, and the sidewalls of the groove extend obliquely and form an obtuse angle with the bottom surface.

10. The display panel according to claim 1, characterized in that, Also includes: An inorganic encapsulation layer is disposed between the light-emitting layer and the first organic encapsulation layer; A cover plate is disposed on the side of the second organic encapsulation layer away from the first organic encapsulation layer.

11. A display device, characterized in that, Includes the display panel as described in any one of claims 1-10.

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