Display panel, preparation method thereof and display device

Abstract

The invention provides a display panel, a preparation method thereof and a display device, the display panel is provided with a pixel area and a non-pixel area surrounding the pixel area, and the display panel comprises a substrate; the first electrode layer is located on one side of the substrate, the first electrode layer comprises a plurality of first electrodes arranged at intervals, and the first electrodes are located in the pixel area; the first electrode comprises a first sub-electrode and a second sub-electrode which are sequentially stacked in the direction away from the substrate. The reflection structure is arranged between the first sub-electrode and the second sub-electrode, a through hole is formed in the reflection structure, and the first sub-electrode and the second sub-electrode are electrically connected through the through hole. According to the technical scheme, the light emitting efficiency can be improved.

Description

Technical Field

[0001] The present application relates to the field of display technology, and in particular to a display panel and a method for preparing the same, and a display device. Background Art

[0002] With the development of display technology, higher brightness, longer life, and higher color gamut have become the highlights of product promotion (for example, mobile phones, tablets, TVs, etc.). Organic Light Emitting Diode (OLED) combined with Quantum Dot (QD) display technology can improve the color gamut value and viewing angle of the display screen, and has obvious advantages in medium and large-sized display screens. In particular, when OLED selects a blue light emitting unit, its red, green, and blue color spectra are discrete, the color purity is high, and the color reproducibility is good. However, the combination of blue light OLED and QD technology still faces some problems, which restricts its widespread commercial application. Summary of the invention

[0003] In order to solve the above problems, embodiments of the present application provide a display panel and a method for manufacturing the same, and a display device.

[0004] In a first aspect, an embodiment of the present application provides a display panel having a pixel area and a non-pixel area surrounding the pixel area, the display panel comprising: a substrate; a first electrode layer located on one side of the substrate, the first electrode layer comprising a plurality of first electrodes arranged at intervals, the first electrode being located in the pixel area; the first electrode comprising a first sub-electrode and a second sub-electrode stacked in sequence in a direction away from the substrate; and a reflective structure arranged between the first sub-electrode and the second sub-electrode, the reflective structure being provided with a through hole, the first sub-electrode and the second sub-electrode being electrically connected through the through hole.

[0005] In combination with the first aspect, the reflective structure includes a plurality of film layers stacked together, and the refractive indices of adjacent film layers are different; preferably, the reflective structure includes at least one first film layer and at least one second film layer, and the first film layers and the second film layers are alternately stacked; preferably, the refractive index of the first film layer is greater than the refractive index of the second film layer; preferably, the difference between the refractive index of the first film layer and the refractive index of the second film layer is greater than or equal to 0.2; preferably, the refractive index range of the first film layer is 1.8 to 2.2, and the refractive index range of the second film layer is 1.4 to 1.5; preferably, the material of the first film layer includes at least one of silicon nitride, silicon oxynitride or titanium oxide, and the material of the second film layer includes silicon oxide; preferably, the number of layers of the first film layer is greater than or equal to 3, and / or the number of layers of the second film layer is greater than or equal to 3. The number is greater than or equal to 3; preferably, the number of layers of the first film layer is equal to the number of layers of the second film layer; preferably, the thickness range of the first film layer is 45-80nm, and the thickness range of the second film layer is 70-100nm; preferably, the display panel also includes a pixel definition layer, the pixel definition layer and the first electrode layer are located on the same side of the substrate, the pixel definition layer encloses a plurality of openings, and the orthographic projection of the first electrode on the substrate is located within the orthographic projection range of the opening on the substrate; preferably, the reflective structure and the pixel definition layer are in the same layer; preferably, the reflective structure and the pixel definition layer are an integrated structure; preferably, the thickness of the reflective structure is greater than or equal to 100nm and less than or equal to 800nm, or the thickness of the pixel definition layer is greater than or equal to 100nm and less than or equal to 800nm.

[0006] In combination with the first aspect, the display panel also includes a light-emitting functional layer, which is located on the side of the first electrode layer away from the substrate; the light-emitting functional layer includes a plurality of stacked light-emitting functional sublayers and a charge generating layer arranged between adjacent light-emitting functional sublayers; preferably, the light-emitting functional sublayer includes a blue light-emitting functional sublayer or a green light-emitting functional sublayer; preferably, the pixel area includes a green sub-pixel area, and the green light-emitting functional sublayer is arranged in the green sub-pixel area.

[0007] In combination with the first aspect, the pixel area includes a green sub-pixel area and a blue sub-pixel area, the multiple reflective structures include a first reflective structure and a second reflective structure, the first reflective structure is arranged in the green sub-pixel area, the second reflective structure is arranged in the blue sub-pixel area, and the thickness of the first reflective structure is greater than the thickness of the second reflective structure; preferably, the thickness range of the first reflective structure is greater than or equal to 580nm and less than or equal to 620nm, and the thickness range of the second reflective structure is greater than or equal to 540nm and less than or equal to 580nm; preferably, the reflective structure includes at least one first film layer and at least one second film layer, the first film layer and the second film layer are alternately stacked, the refractive index of the first film layer is greater than the refractive index of the second film layer, and the thickness of the first film layer of the first reflective structure is greater than the thickness of the first film layer of the second reflective structure degree, and / or the thickness of the second film layer of the first reflective structure is greater than the thickness of the second film layer of the second reflective structure; or, the reflective structure includes a plurality of film layers stacked, and the number of film layers of the first reflective structure is greater than the number of film layers of the second reflective structure; preferably, the display panel further includes a light-emitting functional layer, which is located on the side of the first electrode layer away from the substrate, and the display panel further includes a second electrode layer, which is located on the side of the light-emitting functional layer away from the substrate; the distance between the first sub-electrode and the second electrode layer in the green sub-pixel region is greater than the distance between the first sub-electrode and the second electrode layer in the blue sub-pixel region; preferably, the pixel region further includes a red sub-pixel region, the reflective structure includes a third reflective structure, the third reflective structure is arranged in the red sub-pixel region, and the thickness of the third reflective structure is the same as the thickness of the second reflective structure;

[0008] Preferably, the distance between the first sub-electrode and the second electrode layer in the red sub-pixel region is equal to the distance between the first sub-electrode and the second electrode layer in the blue sub-pixel region.

[0009] In combination with the first aspect, the first electrode further includes a third sub-electrode, and the third sub-electrode is located between the substrate and the first sub-electrode; preferably, the material of the first sub-electrode includes a metal material, and the materials of the second sub-electrode and the third sub-electrode include a transparent conductive material.

[0010] In combination with the first aspect, the display panel further includes: a light-emitting functional layer, located on the side of the first electrode layer away from the substrate, and the display panel further includes a second electrode layer, located on the side of the light-emitting functional layer away from the substrate; preferably, the display panel further includes a light conversion layer, located on the side of the second electrode layer away from the substrate, the light conversion layer includes a quantum dot unit and a first retaining wall structure arranged between adjacent quantum dot units, the quantum dot unit is at least located in the pixel area, and the first retaining wall structure is located in the non-pixel area; the pixel area includes a red sub-pixel area, a green sub-pixel area and a blue sub-pixel area, the quantum dot unit includes a red quantum dot unit, a green quantum dot unit and a blank quantum dot unit, the red quantum dot unit is located in the red sub-pixel area, the green quantum dot unit is located in the green sub-pixel area, and the blank quantum dot unit is located in the blue sub-pixel area; preferably, the display panel further includes a first encapsulation layer, located between the light conversion layer and the second electrode layer; preferably, the display panel also It includes a second encapsulation layer, which is located on the side of the light conversion layer away from the substrate; preferably, the first encapsulation layer and the second encapsulation layer respectively include a first inorganic encapsulation layer, an organic encapsulation layer and a second inorganic encapsulation layer; preferably, the display panel also includes a color filter layer, the color filter layer is located on the side of the second encapsulation layer away from the substrate, the color filter layer includes a plurality of color resist units and a second retaining wall structure arranged between adjacent color resist units, the color resist unit is at least located in the pixel area, and the second retaining wall structure is located in the non-pixel area; preferably, the color resist unit includes a red color resist unit, a green color resist unit and a blue color resist unit, the red color resist unit is located in the red sub-pixel area, the green color resist unit is located in the green sub-pixel area, and the blue color resist unit is located in the blue sub-pixel area; preferably, the display panel also includes an inorganic layer, which is located between the color filter layer and the second encapsulation layer, and the refractive index of the inorganic layer is greater than or equal to 1.2 and less than or equal to 1.4; preferably, the material of the inorganic layer includes silicon dioxide.

[0011] In a second aspect, an embodiment of the present application provides a method for preparing a display panel, wherein the display panel includes a pixel area and a non-pixel area surrounding the pixel area, the method including: forming a first conductive layer on one side of a substrate, the first conductive layer including a plurality of first sub-electrodes arranged at intervals, the first sub-electrodes being located in the pixel area; forming an inorganic film layer on a side of the first conductive layer away from the substrate, patterning the inorganic film layer to obtain a reflective structure and a pixel definition layer, wherein the reflective structure is located on a surface of the first sub-electrode away from the substrate, the reflective structure being provided with a through hole; the pixel definition layer encloses a plurality of openings, the orthographic projection of the first sub-electrode on the substrate being located within the range of the orthographic projection of the opening on the substrate; forming a second conductive layer on a surface of the reflective structure away from the substrate, the second conductive layer including a plurality of second sub-electrodes arranged at intervals, the second sub-electrodes being located in the pixel area, the second sub-electrodes being electrically connected to the first sub-electrode through the through hole.

[0012] In combination with the second aspect, an inorganic film layer is formed on the side of the first conductive layer facing away from the substrate, including: at least one first inorganic film layer and at least one second inorganic film layer are alternately formed in sequence on the side of the first conductive layer facing away from the substrate, and the refractive index of the first inorganic film layer is different from the refractive index of the second inorganic film layer; preferably, the inorganic film layer is patterned to obtain a reflective structure, including: etching the inorganic film layer to form a through hole to obtain a reflective structure; preferably, the pixel area includes a red sub-pixel area, a green sub-pixel area and a blue sub-pixel area; after patterning the inorganic film layer, the method also includes: thinning the patterned inorganic film layer located in the blue sub-pixel area and / or the red sub-pixel area to obtain a reflective structure.

[0013] In combination with the second aspect, after the step of forming a second conductive layer on a surface of the reflective structure away from the substrate, the method further includes: forming a light-emitting functional layer on a side of the second conductive layer away from the substrate; forming a second electrode layer on a side of the light-emitting functional layer away from the substrate; forming a first encapsulation layer on a side of the second electrode layer away from the substrate; forming a light conversion layer on a side of the first encapsulation layer away from the substrate, the light conversion layer including a quantum dot unit and a first retaining wall structure arranged between adjacent quantum dot units, the quantum dot unit is at least located in a pixel area, and the first retaining wall structure is located in a non-pixel area; preferably, before forming the first conductive layer on one side of the substrate, the method further includes: forming a third conductive layer on one side of the substrate, The third conductive layer includes a plurality of third sub-electrodes arranged at intervals, and the third sub-electrodes are located in the pixel area, wherein the first sub-electrode, the second sub-electrode and the third sub-electrode constitute a first electrode; preferably, after the step of forming a light conversion layer on the side of the first encapsulation layer facing away from the substrate, the method further includes: forming a second encapsulation layer on the side of the light conversion layer facing away from the substrate; preferably, after the step of forming the second encapsulation layer on the side of the light conversion layer facing away from the substrate, the method further includes: forming a color filter layer on the side of the second encapsulation layer facing away from the substrate; preferably, before the step of forming a color filter layer on the side of the second encapsulation layer facing away from the substrate, the method further includes: forming an inorganic layer on the side of the second encapsulation layer facing away from the substrate.

[0014] In a third aspect, an embodiment of the present application provides a display device, comprising the above-mentioned display panel, or a display panel prepared by the above-mentioned method.

[0015] Through the above technical solution, by setting a reflective structure between the first sub-electrode and the second sub-electrode, the reflectivity of the light irradiated to the first sub-electrode can be enhanced, and the situation where the reflectivity of the light (for example, blue light) is low can be improved; and it is helpful to improve the color conversion efficiency of the quantum dot unit and the overall light extraction efficiency. At this time, the thickness of the light conversion layer can be appropriately reduced to save costs. In addition, by setting a reflective structure, the optical cavity length can be adjusted to further improve the light extraction efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1It is a schematic diagram of the pixel arrangement structure of a display panel provided in one embodiment of the present application.

[0017] Figure 2 It is a schematic diagram of the cross-sectional structure of a display panel provided in one embodiment of the present application.

[0018] Figure 3 yes Figure 2 A magnified view of the reflection structure in area A.

[0019] Figure 4 It is a schematic diagram of the cross-sectional structure of a display panel provided in yet another embodiment of the present application.

[0020] Figure 5 It is a schematic diagram of the cross-sectional structure of a display panel provided in yet another embodiment of the present application.

[0021] Figure 6 It is a schematic diagram of a process of manufacturing a display panel provided in one embodiment of the present application.

[0022] Figures 7a to 7e It is a structural schematic diagram of a method for preparing a display panel provided in one embodiment of the present application.

[0023] Figure 8 It is a schematic diagram of the structure of a display device provided in one embodiment of the present application. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0025] At present, the three mainstream display technologies include red, green and blue (RGB)-OLED technology, white light OLED + color filter (CF) technology, and blue light OLED + QD technology. Among them, RGB-OLED technology has better overall power consumption and brightness, but it is difficult to achieve large-scale preparation due to the limitations of the preparation process; compared with white light OLED + CF technology, the display panel prepared by blue light OLED + QD technology has discrete red, green and blue spectra, high color purity and good color reproducibility. However, the luminous efficiency and life of blue light fluorescent materials are relatively low, and the color conversion efficiency of QD materials is relatively low, which makes the overall brightness of the display panel darker.

[0026] In view of the above technical problems, on the first aspect, an embodiment of the present application provides a display panel that can improve the light extraction efficiency and the brightness of the display panel. The display panel has a pixel area and a non-pixel area surrounding the pixel area, and the display panel includes: a substrate; a first electrode layer, located on one side of the substrate, the first electrode layer includes a plurality of first electrodes arranged at intervals, and the first electrode is located in the pixel area; the first electrode includes a first sub-electrode and a second sub-electrode stacked in sequence in a direction away from the substrate. The display panel also includes a reflective structure, which is arranged between the first sub-electrode and the second sub-electrode, and a through hole is arranged on the reflective structure, and the first sub-electrode and the second sub-electrode are electrically connected through the through hole. In an embodiment of the present application, by setting a reflective structure, the reflectivity of the light irradiated on the first sub-electrode can be enhanced, which helps to improve the light extraction efficiency; in addition, the reflective structure can also adjust the optical cavity length to further improve the light extraction efficiency.

[0027] Figure 1 It is a schematic diagram of the pixel arrangement structure of a display panel provided in one embodiment of the present application. Figure 2 is a schematic diagram of a cross-sectional structure of a display panel provided in an embodiment of the present application. Optionally, Figure 2 yes Figure 1 The cross-sectional view of the display panel along the mn line. Figure 1 and Figure 2 As shown, the display panel includes a pixel area P1 and a non-pixel area P2 surrounding the pixel area P1, and the pixel area P1 includes a red sub-pixel area PR, a green sub-pixel area PG, and a blue sub-pixel area PB. It can be understood that the pixel arrangement structure in the embodiment of the present application is only an example, and the display panel may also have other pixel arrangement structures, which are not limited in the present application. Figure 2 As shown, the display panel includes a substrate 10 , a first electrode layer 21 and a reflective structure 30 .

[0028] In an embodiment of the present application, the substrate 10 includes a rigid substrate, such as a glass substrate; or, the substrate 10 includes a flexible substrate, such as polyimide (PI), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), etc.

[0029] In the embodiment of the present application, the first electrode layer 21 is located on one side of the substrate 10. The first electrode layer 21 includes a plurality of first electrodes 210 arranged at intervals. The first electrode 210 is located in the pixel area P1, and the first electrode 210 includes a first sub-electrode 211 and a second sub-electrode 212 stacked in sequence in a direction away from the substrate 10. Optionally, the first electrode 210 also includes a third sub-electrode 213, and the third sub-electrode 213 is located between the substrate 10 and the first sub-electrode 211. The material of the first sub-electrode 211 includes a metal material, such as gold, silver, aluminum, etc. The material of the second sub-electrode 212 and the third sub-electrode 213 includes a transparent conductive material, such as indium tin oxide (Indium tin oxide, ITO), fluorine-doped tin oxide (Fluorine-doped Tin Oxide, FTO), aluminum zinc oxide (Aluminum Zinc Oxide, AZO), gallium zinc oxide (Gallium Zinc Oxide, GZO), indium zinc oxide (Indium Zinc Oxide, IZO), etc., preferably ITO.

[0030] In an embodiment of the present application, the display panel also includes a reflective structure 30. The reflective structure 30 is disposed between the first sub-electrode 211 and the second sub-electrode 212, and a through hole 301 is disposed on the reflective structure 30, through which the first sub-electrode 211 and the second sub-electrode 212 are electrically connected. In an embodiment of the present application, the reflective structure 30 is a distributed Bragg reflector (DBR) structure, which is used to improve the reflectivity of light and thus improve the light extraction efficiency. Specifically, the reflective structure 30 includes a plurality of film layers stacked together, and adjacent film layers have different refractive indices. When light passes through film layers with different refractive indices, the light reflected back from each film layer is enhanced and interfered due to the change in phase angle, thereby obtaining a strong reflected light and improving the reflectivity of the light. Figure 3 yes Figure 2 A magnified view of the reflection structure in area A. Figure 3As shown, the reflective structure includes at least one first film layer 310 and at least one second film layer 320, and the first film layer 310 and the second film layer 320 are alternately stacked. Optionally, the refractive index of the first film layer 310 is greater than the refractive index of the second film layer 320, and the difference between the refractive index of the first film layer 310 and the refractive index of the second film layer 320 is greater than or equal to 0.2. Preferably, the refractive index of the first film layer 310 ranges from 1.8 to 2.2. Exemplarily, the refractive index of the first film layer 310 is 1.8, 1.9, 2, 2.1, 2.2. The refractive index of the second film layer 320 ranges from 1.4 to 1.5. Exemplarily, the refractive index of the second film layer 320 is 1.4, 1.45, 1.5. Exemplarily, the material of the first film layer 310 includes at least one of silicon nitride, silicon oxynitride, and titanium oxide, and the material of the second film layer 320 includes silicon oxide. Optionally, the thickness of the first film layer 310 and the second film layer 320 needs to satisfy the relationship: n1H1=n2H2=λ / 4, wherein n1 is the refractive index of the first film layer 310, n2 is the refractive index of the second film layer 320, H1 is the thickness of the first film layer 310, H2 is the thickness of the second film layer 320, and λ is the wavelength of the light emitted by the light-emitting functional unit, for example, the wavelength of the light emitted by the blue light-emitting functional unit (the blue light-emitting functional sublayer described below), or the wavelength of the light emitted by the green light-emitting functional unit (the green light-emitting functional sublayer described below). In the embodiment of the present application, the thickness H1 of the first film layer 310 ranges from 45 to 80 nm, and the thickness H2 of the second film layer 320 ranges from 70 to 100 nm. Exemplarily, the thickness H1 of the first film layer 310 is 45 nm, 50 nm, 55 nm, 60 nm, 65 nm, 70 nm, 75 nm, 80 nm. The thickness H2 of the second film layer 320 is 70nm, 75nm, 80nm, 85nm, 90nm, 95nm, and 100nm. It can be understood that the more film layers there are, the better the enhanced reflection effect is. Optionally, the number of layers of the first film layer 310 is greater than or equal to 3, and / or the number of layers of the second film layer 320 is greater than or equal to 3. Preferably, the number of layers of the first film layer 310 is equal to the number of layers of the second film layer 320. That is, the reflective structure 30 includes at least three groups of film layers with different refractive indices. In addition, the optical cavity length is adjusted by adjusting the thickness of the reflective structure 30 (for example, adjusting the number of film layers, or adjusting the thickness of the first film layer and / or the second film layer), thereby enhancing the light extraction efficiency.

[0031] Optionally, the display panel further includes a pixel definition layer 40. The pixel definition layer 40 and the first electrode layer 21 are located on the same side of the substrate 10, the pixel definition layer 40 encloses a plurality of openings, and the orthographic projection of the first electrode layer 210 on the substrate 10 is located within the orthographic projection range of the openings on the substrate 10. Optionally, the reflective structure 30 and the pixel definition layer 40 are in the same layer. Optionally, the reflective structure 30 and the pixel definition layer 40 are an integral structure. That is, in the embodiment of the present application, the reflective structure 30 and the pixel definition layer 40 are made of the same material and are integrally formed in the same process. It is understood that in other embodiments, the reflective structure 30 and the pixel definition layer 40 are prepared in different processes, in which case the reflective structure 30 and the pixel definition layer 40 are made of different materials, and the material of the pixel definition layer 40 includes an organic material or an inorganic material. The thickness of the reflective structure 30 is greater than or equal to 100 nm and less than or equal to 800 nm. The thickness of the pixel definition layer 40 is greater than or equal to 100 nm and less than or equal to 800 nm. Exemplarily, the thickness of the reflective structure 30 is 100nm, 150nm, 200nm, 250nm, 300nm, 350nm, 400nm, 450nm, 500nm, 600nm, 700nm, 800nm. The thickness of the pixel definition layer 40 is 100nm, 150nm, 200nm, 250nm, 300nm, 350nm, 400nm, 450nm, 500nm, 600nm, 700nm, 800nm.

[0032] Continue to refer Figure 2 , the display panel further includes a light-emitting functional layer 22. The light-emitting functional layer 22 is located on the side of the first electrode layer 21 away from the substrate 10. The light emitted by the light-emitting functional layer 22 can be directly emitted to the light-emitting side, or can be emitted to the side of the first electrode 211. When the light is irradiated to the first electrode 211, it is reflected on the surface of the first electrode 211, and after passing through the reflective structure 30, the reflected light can be enhanced. In the embodiment of the present application, the light-emitting functional layer 22 includes a blue light-emitting functional sublayer 221. In this case, the thickness of the first film layer 310 and the second film layer 320 is determined according to the wavelength λ of the light emitted by the blue light-emitting functional sublayer to enhance the blue light after reflection; in addition, the thickness of the reflective structure 30 can be adjusted (for example, the number of film layers of the reflective structure 30 is adjusted, or the thickness of the first film layer 310 and / or the second film layer 320 is adjusted) so that the blue light-emitting functional sublayer has a better optical cavity length, and the light-emitting efficiency and light-emitting efficiency are enhanced.

[0033] Optionally, the display panel further includes a second electrode layer 23. The second electrode layer 23 is located on the side of the light-emitting functional layer 22 away from the substrate 10. The material of the second electrode layer 23 includes metal (e.g., silver, aluminum, calcium, indium, lithium, magnesium), alloy (e.g., magnesium-silver alloy, lithium-aluminum alloy), etc.

[0034] Continue to refer Figure 2 The display panel further includes a first encapsulation layer 51, a light conversion layer 60, and a second encapsulation layer 52 stacked in sequence in a direction away from the substrate 10. Optionally, the first encapsulation layer 51 and the second encapsulation layer 52 include a first inorganic encapsulation layer, an organic encapsulation layer, and a second inorganic encapsulation layer, respectively. Optionally, the material of the first inorganic encapsulation layer and the second inorganic encapsulation layer includes at least one of silicon oxide, silicon nitride, and silicon oxynitride. In some embodiments, the first encapsulation layer 51 can be omitted, and the light conversion layer 60 is directly disposed on the second electrode layer 23 (in order to avoid damaging the light-emitting functional layer 22, an inorganic protective layer can be disposed on the second electrode layer 23).

[0035] In the embodiment of the present application, the light conversion layer 60 includes a quantum dot unit 610 and a first retaining wall structure 620 disposed between adjacent quantum dot units. The quantum dot unit 610 is at least located in the pixel area P1, and the first retaining wall structure 620 is located in the non-pixel area. The quantum dot unit 610 includes a red quantum dot unit 611, a green quantum dot unit 612, and a blank quantum dot unit 613. The red quantum dot unit 611 is formed of a red quantum dot material, and the green quantum dot unit 612 is formed of a green quantum dot material. The red quantum dot material and / or the green quantum dot material are conventional materials in the art and are not limited here. Figure 2 As shown, the pixel area P1 includes a red sub-pixel area PR, a green sub-pixel area PG and a blue sub-pixel area PB. The red quantum dot unit 611 is located in the red sub-pixel area PR, the green quantum dot unit 612 is located in the green sub-pixel area PG, and the blank quantum dot unit 613 is located in the blue sub-pixel area PB. In the embodiment of the present application, the first retaining wall structure 620 is a black material, such as a black organic material or a black metal material. When the black material is used to separate the quantum dot unit 610, light crosstalk can be better reduced.

[0036] In the embodiment of the present application, by setting the reflective structure 30 between the first sub-electrode 211 and the second sub-electrode 212, the reflectivity of the light irradiated to the first sub-electrode 211 can be enhanced, the situation of low reflectivity of the light (for example, blue light) can be improved, and the light extraction efficiency (for example, blue light extraction efficiency) can be improved; and it is helpful to improve the color conversion efficiency of the red quantum dot unit and the green quantum dot unit, improve the light extraction efficiency of the red converted light and the green converted light, and appropriately reduce the thickness of the light conversion layer to save costs. In addition, by setting the reflective structure 30, the optical cavity length can be adjusted to further improve the light extraction efficiency.

[0037] Since the efficiency and life of blue light emitting materials are relatively low, in order to improve the efficiency and life of blue light emitting, a tandem OLED can be used, and green light emitting materials can be used to increase the display brightness of green light. It is difficult for the same optical cavity length to simultaneously meet the optimal emission conditions of blue and green light. In this application scheme, the reflective structures in the green sub-pixel area and the blue sub-pixel area can be designed with different thicknesses to meet the optimal optical cavity lengths of blue and green light, respectively, and improve light emission efficiency. For details, please refer to Figure 4 Related description in .

[0038] Figure 4 FIG. 1 is a schematic diagram of a cross-sectional structure of a display panel provided by another embodiment of the present application. Figure 4 As shown, the display panel Figure 2 The difference of the display panel shown is that the light-emitting functional layer 22 includes a plurality of stacked light-emitting functional sublayers and a charge generation layer arranged between adjacent light-emitting functional sublayers. Adjacent light-emitting functional sublayers are connected in series via the charge generation layer. Figure 4 In the figure, the light-emitting functional layer 22 includes a blue light-emitting functional sublayer 221, a green light-emitting functional sublayer 222 and a blue light-emitting functional sublayer 221 which are sequentially stacked in a direction away from the substrate. A charge generating layer 223 is arranged between the blue light-emitting functional sublayer 221 and the green light-emitting functional sublayer 222. It can be understood that only one stacking structure of the light-emitting functional sublayer is shown here, and those skilled in the art can adopt other stacking structures according to actual needs, for example, multiple blue light-emitting functional sublayers are stacked; multiple blue light-emitting functional sublayers and multiple green light-emitting functional sublayers are stacked, etc. Optionally, due to the low light output rate of green light, the green light can be enhanced by setting a green light-emitting functional sublayer. In some embodiments, the green light-emitting functional sublayer is arranged in the green sub-pixel area PG to enhance the green light. In some embodiments, in order to simplify the preparation process, the green light-emitting functional sublayer can be arranged as a whole layer, such as Figure 4 shown.

[0039] The optical cavity length refers to the distance from the first sub-electrode 211 to the second electrode layer 23. The optimal optical cavity length and wavelength need to satisfy nλ=2L, where n is an integer, λ is the wavelength, and L is the length of the optical cavity length. Since the optimal optical cavity length is related to the wavelength, the wavelengths of green light and blue light are different, so the optimal optical cavity lengths of green light and blue light are different. In the embodiment of the present application, the light-emitting functional layer 22 includes a blue light-emitting functional sublayer 221 and a green light-emitting functional sublayer 222. Therefore, it is necessary to satisfy the optical cavity lengths of blue light and green light respectively to improve the light extraction efficiency. Figure 4As shown, the distance (i.e., optical cavity length) L1 between the first sub-electrode 211 and the second electrode layer 23 of the green sub-pixel region PG is greater than the distance (i.e., optical cavity length) L2 between the first sub-electrode 211 and the second electrode layer 23 of the blue sub-pixel region PB, and the distance (i.e., optical cavity length) L3 between the first sub-electrode 211 and the second electrode layer 23 of the red sub-pixel region PR is equal to the distance (i.e., optical cavity length) L2 between the first sub-electrode 211 and the second electrode layer 23 of the blue sub-pixel region PB. It can be understood that Figure 4 The lengths of L1, L2, and L3 are for illustration only. Since the length difference between L1 and L2 is only a few tens of nanometers, Figure 4 The length difference between L1 and L2 is not clearly reflected in the figure. In the embodiment of the present application, the optical cavity length can be adjusted by adjusting the thickness of the reflective structure 30 in different sub-pixel regions.

[0040] In the embodiment of the present application, the reflective structure 30 includes a first reflective structure 31, a second reflective structure 32 and a third reflective structure 33. The first reflective structure 31 is arranged in the green sub-pixel area PG, the second reflective structure 32 is arranged in the blue sub-pixel area PB, and the third reflective structure 33 is arranged in the red sub-pixel area PR. The thickness of the first reflective structure 31 is greater than the thickness of the second reflective structure 32, and the thickness of the third reflective structure 33 is the same as the thickness of the second reflective structure 32. Optionally, the thickness range of the first reflective structure 31 is greater than or equal to 580nm and less than or equal to 620nm, and the thickness range of the second reflective structure 32 is greater than or equal to 540nm and less than or equal to 580nm. Exemplarily, the thickness of the first reflective structure 31 is 580nm, 590nm, 600nm, 610nm, 620nm. The thickness of the second reflective structure 32 is 540nm, 550nm, 560nm, 570nm, 580nm. In the embodiment of the present application, the thickness of the reflective structure 30 can be adjusted by adjusting the thickness of the first film layer 310 and / or the second film layer 320 of the reflective structure 30. For example, the thickness of the first film layer 310 of the first reflective structure 31 is greater than the thickness of the first film layer 310 of the second reflective structure 32, and / or the thickness of the second film layer 320 of the first reflective structure 31 is greater than the thickness of the second film layer 320 of the second reflective structure 32. Exemplarily, the first reflective structure 31 and the second reflective structure 32 both include four first film layers 310 and four second film layers 320, the thickness of the first film layer 310 of the first reflective structure 31 is 60nm, the thickness of the second film layer 320 is 90nm, and the thickness of the first reflective structure 31 is 600nm. The thickness of the first film layer 310 of the second reflective structure 32 is 60nm, the thickness of the second film layer 320 is 80nm, and the thickness of the second reflective structure 32 is 560nm. The thickness of the third reflective structure 33 is equal to that of the second reflective structure 32, which is 560 nm. In the embodiment of the present application, the optimal optical cavity length of green light and blue light is achieved by adjusting the thickness of the reflective structures located in different sub-pixel regions. It can be understood that Figure 4 For illustration only, Figure 4 The difference in thickness between the first reflective structure 31 and the second reflective structure 32 is not clearly reflected in the figure.

[0041] Since the reflective structure 30 includes a plurality of stacked film layers, in other embodiments, the thickness of the reflective structure 30 can be adjusted by changing the number of film layers. Optionally, the number of film layers of the first reflective structure 31 is greater than the number of film layers of the second reflective structure 32; the number of film layers of the second reflective structure 32 and the third reflective structure 33 are the same.

[0042] In the embodiment of the present application, since the blue light emitting functional sublayer and the green light emitting functional sublayer exist at the same time, the reflective structure located in the blue sub-pixel area and the reflective structure located in the green sub-pixel area are set with different thicknesses, so that the blue light emitting functional sublayer and the green light emitting functional sublayer both reach the optimal optical cavity length, thereby improving the light output efficiency.

[0043] Figure 5 FIG. 1 is a schematic diagram of a cross-sectional structure of a display panel provided by another embodiment of the present application. Figure 5 As shown, the display panel Figure 4 The difference of the display panel shown is that the display panel further includes an inorganic layer 70 and a color filter layer 80. The color filter layer 80 is located on the side of the second encapsulation layer 52 away from the substrate 10. The color filter layer 80 includes a plurality of color resist units 810 and a second retaining wall structure 820 arranged between adjacent color resist units 810. The color resist unit 810 is at least located in the pixel area P1, and the second retaining wall structure 820 is located in the non-pixel area P2. Optionally, the color resist unit 810 includes a red color resist unit 811, a green color resist unit 812, and a blue color resist unit 813. The red color resist unit 811 is located in the red sub-pixel area, the green color resist unit 812 is located in the green sub-pixel area, and the blue color resist unit 813 is located in the blue sub-pixel area. The second retaining wall 820 includes a black material, for example, a black organic material or a black metal material. Optionally, the material of the second retaining wall structure 820 may be the same as or different from the material of the first retaining wall structure 620. By providing the color filter layer 80 , the crosstalk of light emitted by different light-emitting units can be reduced and the color saturation of the light emitted can be improved.

[0044] The inorganic layer 70 is disposed between the second encapsulation layer 52 and the color filter layer 80. Optionally, the inorganic layer 70 is a low refractive index material. Optionally, the refractive index of the inorganic layer 70 is greater than or equal to 1.2 and less than or equal to 1.4. Exemplarily, the refractive index of the inorganic layer 70 is 1.2, 1.3, 1.4. Optionally, the material of the inorganic layer includes silicon dioxide (e.g., hollow silicon dioxide). The light extraction efficiency can be further improved by providing the inorganic layer 70.

[0045] In a second aspect, the present application provides a method for preparing a display panel, which is used to prepare the display panel in the above embodiment.

[0046] Figure 6 The display panel includes a pixel region and a non-pixel region surrounding the pixel region. Figures 7a to 7e FIG. 1 is a schematic diagram of a method for manufacturing a display panel according to an embodiment of the present application. Figure 6 As shown, the method includes the following steps.

[0047] Step S610: forming a first conductive layer on one side of the substrate.

[0048] The material of the first conductive layer includes metal, such as silver, gold, aluminum, etc. The present application does not limit the method for preparing the first conductive layer, as long as the first conductive layer can be obtained. For example, a mask plate is used to prepare the first conductive layer on one side of the substrate by magnetron sputtering. Figure 7a As shown, the first conductive layer includes a plurality of first sub-electrodes 211 arranged at intervals, and the first sub-electrodes 211 are located in the pixel region P1.

[0049] Optionally, before the first conductive layer is formed on one side of the substrate, the method further includes forming a third conductive layer on one side of the substrate. The material of the third conductive layer includes a transparent conductive material, such as ITO. The present application does not limit the method for preparing the third conductive layer, as long as the third conductive layer can be obtained. For example, a mask plate is used to prepare the third conductive layer on one side of the substrate by magnetron sputtering. Figure 7a As shown, the third conductive layer includes a plurality of third sub-electrodes 213 arranged at intervals, and the third sub-electrodes 213 are located in the pixel region P1.

[0050] Step S620 , forming an inorganic film layer on the side of the first conductive layer facing away from the substrate, and patterning the inorganic film layer to obtain a reflective structure and a pixel definition layer.

[0051] Optionally, at least one first inorganic film layer and at least one second inorganic film layer are alternately formed in sequence on the side of the first conductive layer facing away from the substrate, and the refractive index of the first inorganic film layer is different from the refractive index of the second inorganic film layer. Optionally, the inorganic film layer is etched to form a through hole to obtain a reflective structure. In an embodiment of the present application, the reflective structure and the pixel definition layer are prepared in the same layer, and no additional process is required. The portion of the inorganic film layer located in the pixel area constitutes the reflective structure, and the portion of the inorganic film layer located in the non-pixel area constitutes the pixel definition layer. Figure 7b As shown, the reflective structure 30 is located on the surface of the first sub-electrode 211 away from the substrate, and the reflective structure 30 is provided with a through hole 301. The pixel definition layer 40 encloses a plurality of openings, and the orthographic projection of the first sub-electrode 211 on the substrate 10 is located within the orthographic projection of the opening on the substrate 10.

[0052] In some embodiments, in order to improve the life and brightness of the display panel, optionally, the light-emitting functional layer is provided with a blue light-emitting functional sublayer and a green light-emitting functional sublayer at the same time. At this time, in order to ensure that the blue light-emitting functional sublayer and the green light-emitting functional sublayer both reach the optimal optical cavity length, it can be achieved by adjusting the thickness of the reflective structure. Optionally, the pixel area includes a red sub-pixel area, a green sub-pixel area and a blue sub-pixel area. After the inorganic film layer is patterned, the method further includes: thinning the patterned inorganic film layer located in the blue sub-pixel area and the red sub-pixel area to obtain the reflective structure. That is, when preparing the inorganic film layer, the inorganic film layer is first prepared according to the optical cavity length corresponding to the green light-emitting functional sublayer, and the thickness of the inorganic film layer meets the optimal optical cavity length of the green light-emitting functional sublayer; then the inorganic film layer located in the blue sub-pixel area and / or the red sub-pixel area is thinned so that the thickness of the inorganic film layer meets the optimal optical cavity length of the blue light-emitting functional sublayer. Alternatively, after forming each first inorganic film layer or second inorganic film layer, the first inorganic film layer or second inorganic film layer located in the blue sub-pixel area and the red sub-pixel area is thinned so that the thickness of the inorganic film layer finally formed meets the optimal optical cavity length of the blue light emitting functional sublayer.

[0053] Step S630: forming a second conductive layer on the surface of the reflective structure facing away from the substrate.

[0054] The material of the second conductive layer includes a transparent conductive material, for example, ITO. The present application does not limit the method for preparing the second conductive layer, as long as the second conductive layer can be obtained. Exemplarily, the second conductive layer is prepared by magnetron sputtering using a mask.

[0055] like Figure 7c As shown, the second conductive layer includes a plurality of second sub-electrodes 212 arranged at intervals, the second sub-electrodes are located in the pixel region P1, and the second sub-electrodes 212 and the first sub-electrode 211 are electrically connected through the through hole 301. The first sub-electrode 211, the second sub-electrode 212 and the third sub-electrode 213 constitute the first electrode 210.

[0056] Step S640: forming a light-emitting functional layer and a second electrode layer in sequence on a side of the second conductive layer facing away from the substrate.

[0057] In the embodiment of the present application, the luminescent material of the luminescent functional layer is formed by front evaporation, so that the preparation process can be simplified. Optionally, a layer of blue light luminescent material can be evaporated to form a blue light luminescent functional sublayer; or, multiple layers of blue light luminescent material and / or green light luminescent material can be evaporated to form stacked blue light luminescent functional sublayers and green light luminescent functional sublayers respectively. For example, a layer of blue light luminescent material, a layer of green light luminescent material and a layer of blue light luminescent material can be evaporated in sequence to form a blue light luminescent functional sublayer, a green light luminescent functional sublayer and a blue light luminescent functional sublayer stacked in sequence, such as Figure 7d As shown. It can be understood that the light-emitting functional sublayer also includes a hole transport layer, a hole injection layer, an electron transport layer, an electron injection layer, etc. The method also includes preparing a charge generation layer between the light-emitting functional sublayers.

[0058] After the light-emitting functional layer is prepared, a second electrode layer is prepared on the side of the light-emitting functional layer away from the substrate to obtain Figure 7d The present application does not limit the preparation process of the second electrode layer, as long as the second electrode layer can be obtained.

[0059] Step S650: forming a first encapsulation layer and a light conversion layer in sequence on a side of the second electrode layer facing away from the substrate.

[0060] In an embodiment of the present application, a first encapsulation layer is formed on the side of the second electrode layer facing away from the substrate, and the first encapsulation layer includes a first inorganic encapsulation layer, an organic encapsulation layer, and a second inorganic encapsulation layer. Optionally, the first inorganic encapsulation layer and the second inorganic encapsulation layer are prepared by chemical vapor deposition, and the second inorganic encapsulation layer is prepared by inkjet printing.

[0061] A light conversion layer is formed on the side of the first encapsulation layer away from the substrate to obtain Figure 7e The display panel shown. The light conversion layer includes a quantum dot unit and a first retaining wall structure arranged between adjacent quantum dot units, the quantum dot unit is at least located in the pixel area, and the first retaining wall structure is located in the non-pixel area. The first retaining wall structure and the quantum dot unit can be prepared by conventional processes in the art, and this application does not limit them.

[0062] Optionally, after forming the light conversion layer on the side of the first encapsulation layer facing away from the substrate, the method further includes: forming a second encapsulation layer on the side of the light conversion layer facing away from the substrate. The second encapsulation layer includes a first inorganic encapsulation layer, an organic encapsulation layer, and a second inorganic encapsulation layer. Optionally, the first inorganic encapsulation layer and the second inorganic encapsulation layer are prepared by chemical vapor deposition, and the second inorganic encapsulation layer is prepared by inkjet printing.

[0063] Optionally, after forming a second encapsulation layer on the side of the light conversion layer away from the substrate, the method further includes: forming a color filter layer on the side of the second encapsulation layer away from the substrate. The color filter layer includes a plurality of color resist units and a second retaining wall structure disposed between adjacent color resist units. The color resist unit is at least located in the pixel area, and the second retaining wall structure is located in the non-pixel area.

[0064] Optionally, before preparing the color filter layer, the method further comprises: forming an inorganic layer on the side of the second encapsulation layer facing away from the substrate. The material of the inorganic layer comprises silicon dioxide.

[0065] In a third aspect, an embodiment of the present application provides a display device, which includes the display panel described in the above embodiment.

[0066] Figure 8 is a schematic diagram of the structure of a display device provided by an embodiment of the present application. Figure 8 As shown, the display device 800 is a product with an image display function. For example, the display device 800 can be used to display static images, such as pictures or photos. The display device 800 can also be used to display dynamic images, such as videos.

[0067] The display device 800 can be a laptop computer, a mobile phone, a handheld or portable computer, a camera, a camcorder, a vehicle-mounted smart central control screen, a calculator, a smart watch, a GPS navigator, an electronic photo, an electronic billboard or sign, a projector, etc.

[0068] The display device 800 includes a display panel provided by any of the above embodiments, which may be an organic light emitting diode display panel or a quantum dot electroluminescent display panel.

[0069] In addition, the display device 800 may also have functions such as taking pictures, recording, fingerprint recognition, face recognition, etc. Accordingly, the display device 800 also includes at least one functional module for realizing the above functions, such as an under-screen camera, an under-screen fingerprint recognition sensor, etc.

[0070] The basic principles of the present application are described above in conjunction with specific embodiments. However, it should be noted that the advantages, strengths, effects, etc. mentioned in the present application are only examples and not limitations, and it cannot be considered that these advantages, strengths, effects, etc. are required by each embodiment of the present application. In addition, the specific details disclosed above are only for the purpose of illustration and ease of understanding, not for limitation, and the above details do not limit the present application to being implemented by adopting the above specific details.

[0071] The block diagrams of the devices, apparatuses, equipment, and systems involved in this application are only illustrative examples and are not intended to require or imply that they must be connected, arranged, and configured in the manner shown in the block diagrams. As will be appreciated by those skilled in the art, these devices, apparatuses, equipment, and systems can be connected, arranged, and configured in any manner. Words such as "including", "comprising", "having", etc. are open words, referring to "including but not limited to", and can be used interchangeably with them. The words "or" and "and" used here refer to the words "and / or" and can be used interchangeably with them, unless the context clearly indicates otherwise. The words "such as" used here refer to the phrase "such as but not limited to", and can be used interchangeably with them.

[0072] It should also be noted that in the apparatus, device and method of the present application, each component or each step can be decomposed and / or recombined. Such decomposition and / or recombination should be regarded as equivalent solutions of the present application.

[0073] The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use the present application. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other aspects without departing from the scope of the present application. Therefore, the present application is not intended to be limited to the aspects shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

[0074] The above description has been given for the purpose of illustration and description. In addition, this description is not intended to limit the embodiments of the present application to the forms disclosed herein. Although multiple example aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, changes, additions and sub-combinations thereof.

Claims

1. A display panel, characterized in that: The display panel has a pixel area and a non-pixel area surrounding the pixel area, and includes: substrate; a first electrode layer, located on one side of the substrate, the first electrode layer comprising a plurality of first electrodes arranged at intervals, the first electrodes being located in the pixel region; the first electrodes comprising first sub-electrodes and second sub-electrodes sequentially stacked in a direction away from the substrate; and The reflective structure is arranged between the first sub-electrode and the second sub-electrode. A through hole is arranged on the reflective structure. The first sub-electrode and the second sub-electrode are electrically connected through the through hole.

2. The display panel according to claim 1, characterized in that: The reflective structure includes a plurality of film layers stacked together, and the refractive indexes of adjacent film layers are different; Preferably, the reflective structure comprises at least one first film layer and at least one second film layer, and the first film layer and the second film layer are alternately stacked; Preferably, the refractive index of the first film layer is greater than the refractive index of the second film layer; Preferably, the difference between the refractive index of the first film layer and the refractive index of the second film layer is greater than or equal to 0.2; Preferably, the refractive index of the first film layer is in the range of 1.8 to 2.2, and the refractive index of the second film layer is in the range of 1.4 to 1.5; Preferably, the material of the first film layer includes at least one of silicon nitride, silicon oxynitride or titanium oxide, and the material of the second film layer includes silicon oxide; Preferably, the number of layers of the first film layer is greater than or equal to 3, and / or the number of layers of the second film layer is greater than or equal to 3; Preferably, the number of layers of the first film layer is equal to the number of layers of the second film layer; Preferably, the thickness of the first film layer is in the range of 45 to 80 nm, and the thickness of the second film layer is in the range of 70 to 100 nm; Preferably, the display panel further comprises a pixel definition layer, wherein the pixel definition layer and the first electrode layer are located on the same side of the substrate, the pixel definition layer encloses a plurality of openings, and the orthographic projection of the first electrode on the substrate is located within the orthographic projection range of the opening on the substrate; Preferably, the reflective structure and the pixel definition layer are in the same layer; Preferably, the reflective structure and the pixel definition layer are an integrated structure; Preferably, the thickness of the reflective structure is greater than or equal to 100 nm and less than or equal to 800 nm, or the thickness of the pixel definition layer is greater than or equal to 100 nm and less than or equal to 800 nm.

3. The display panel according to claim 1, characterized in that: It also includes a light-emitting functional layer, which is located on the side of the first electrode layer away from the substrate; the light-emitting functional layer includes a plurality of stacked light-emitting functional sublayers and a charge generation layer arranged between adjacent light-emitting functional sublayers; Preferably, the light-emitting functional sublayer includes a blue light-emitting functional sublayer or a green light-emitting functional sublayer; Preferably, the pixel area includes a green sub-pixel area, and the green light emitting functional sub-layer is arranged in the green sub-pixel area.

4. The display panel according to claim 1, characterized in that: The pixel area includes a green sub-pixel area and a blue sub-pixel area; the plurality of reflective structures include a first reflective structure and a second reflective structure, the first reflective structure is arranged in the green sub-pixel area, the second reflective structure is arranged in the blue sub-pixel area, and the thickness of the first reflective structure is greater than the thickness of the second reflective structure; Preferably, the thickness of the first reflective structure is in a range of greater than or equal to 580 nm and less than or equal to 620 nm, and the thickness of the second reflective structure is in a range of greater than or equal to 540 nm and less than or equal to 580 nm; Preferably, the reflective structure includes at least one first film layer and at least one second film layer, the first film layers and the second film layers are alternately stacked, the refractive index of the first film layer is greater than the refractive index of the second film layer, the thickness of the first film layer of the first reflective structure is greater than the thickness of the first film layer of the second reflective structure, and / or the thickness of the second film layer is greater than the thickness of the second film layer of the second reflective structure; or, the reflective structure includes a plurality of film layers stacked, and the number of film layers of the first reflective structure is greater than the number of film layers of the second reflective structure; Preferably, the display panel further comprises a light-emitting functional layer located on a side of the first electrode layer away from the substrate, and the display panel further comprises a second electrode layer located on a side of the light-emitting functional layer away from the substrate; the distance between the first sub-electrode and the second electrode layer in the green sub-pixel region is greater than the distance between the first sub-electrode and the second electrode layer in the blue sub-pixel region; Preferably, the pixel area further includes a red sub-pixel area, the reflective structure includes a third reflective structure, the third reflective structure is arranged in the red sub-pixel area, and the thickness of the third reflective structure is the same as the thickness of the second reflective structure; Preferably, the distance between the first sub-electrode and the second electrode layer in the red sub-pixel region is equal to the distance between the first sub-electrode and the second electrode layer in the blue sub-pixel region.

5. The display panel according to claim 1, characterized in that: The first electrode further includes a third sub-electrode, and the third sub-electrode is located between the substrate and the first sub-electrode; Preferably, the material of the first sub-electrode includes a metal material, and the materials of the second sub-electrode and the third sub-electrode include a transparent conductive material.

6. The display panel according to claim 1, characterized in that: It also includes: a light-emitting functional layer, which is located on a side of the first electrode layer away from the substrate, and the display panel also includes a second electrode layer, which is located on a side of the light-emitting functional layer away from the substrate; Preferably, the display panel further comprises a light conversion layer located on a side of the second electrode layer away from the substrate, the light conversion layer comprises quantum dot units and a first retaining wall structure arranged between adjacent quantum dot units, the quantum dot units are at least located in the pixel area, and the first retaining wall structure is located in the non-pixel area; The pixel area includes a red sub-pixel area, a green sub-pixel area and a blue sub-pixel area, the quantum dot unit includes a red quantum dot unit, a green quantum dot unit and a blank quantum dot unit, the red quantum dot unit is located in the red sub-pixel area, the green quantum dot unit is located in the green sub-pixel area, and the blank quantum dot unit is located in the blue sub-pixel area; Preferably, the display panel further comprises a first encapsulation layer located between the light conversion layer and the second electrode layer; Preferably, the display panel further comprises a second encapsulation layer, which is located on a side of the light conversion layer away from the substrate; Preferably, the first encapsulation layer and the second encapsulation layer include a first inorganic encapsulation layer, an organic encapsulation layer and a second inorganic encapsulation layer, respectively; Preferably, the display panel further comprises a color filter layer, the color filter layer is located on the side of the second encapsulation layer away from the substrate, the color filter layer comprises a plurality of color resist units and a second retaining wall structure arranged between adjacent color resist units, the color resist unit is at least located in the pixel area, and the second retaining wall structure is located in the non-pixel area; Preferably, the color resistance unit includes a red color resistance unit, a green color resistance unit and a blue color resistance unit, the red color resistance unit is located in the red sub-pixel area, the green color resistance unit is located in the green sub-pixel area, and the blue color resistance unit is located in the blue sub-pixel area; Preferably, the display panel further comprises an inorganic layer located between the color filter layer and the second encapsulation layer, and the refractive index of the inorganic layer is greater than or equal to 1.2 and less than or equal to 1.4; Preferably, the material of the inorganic layer includes silicon dioxide.

7. A method for preparing a display panel, characterized in that: The display panel includes a pixel area and a non-pixel area surrounding the pixel area, and the method includes: Forming a first conductive layer on one side of the substrate, the first conductive layer comprising a plurality of first sub-electrodes arranged at intervals, the first sub-electrodes being located in the pixel area; An inorganic film layer is formed on the side of the first conductive layer away from the substrate, and the inorganic film layer is patterned to obtain a reflective structure and a pixel definition layer, wherein the reflective structure is located on the surface of the first sub-electrode away from the substrate, and a through hole is opened in the reflective structure; the pixel definition layer encloses a plurality of openings, and the orthographic projection of the first sub-electrode on the substrate is located within the orthographic projection range of the opening on the substrate; A second conductive layer is formed on a surface of the reflective structure away from the substrate, the second conductive layer includes a plurality of second sub-electrodes arranged at intervals, the second sub-electrodes are located in the pixel area, and the second sub-electrodes are electrically connected to the first sub-electrode through the through hole.

8. The method according to claim 7, characterized in that The step of forming an inorganic film layer on a side of the first conductive layer facing away from the substrate comprises: At least one first inorganic film layer and at least one second inorganic film layer are alternately formed in sequence on a side of the first conductive layer away from the substrate, wherein the refractive index of the first inorganic film layer is different from the refractive index of the second inorganic film layer; Preferably, patterning the inorganic film layer to obtain the reflective structure comprises: etching the inorganic film layer to form the through hole to obtain the reflective structure; Preferably, the pixel area includes a red sub-pixel area, a green sub-pixel area and a blue sub-pixel area; after the inorganic film layer is patterned, the method further includes: thinning the patterned inorganic film layer located in the blue sub-pixel area and the red sub-pixel area to obtain the reflective structure; or, alternately forming at least one first inorganic film layer and at least one second inorganic film layer on the side of the first conductive layer away from the substrate, including: after forming each layer of the first inorganic film layer or the second inorganic film layer, thinning the first inorganic film layer or the second inorganic film layer located in the blue sub-pixel area and the red sub-pixel area.

9. The method according to claim 7, characterized in that: After the step of forming a second conductive layer on a surface of the reflective structure facing away from the substrate, the method further comprises: forming a light-emitting functional layer on a side of the second conductive layer away from the substrate; forming a second electrode layer on a side of the light-emitting functional layer away from the substrate; forming a first encapsulation layer on a side of the second electrode layer away from the substrate; A light conversion layer is formed on a side of the first encapsulation layer away from the substrate, wherein the light conversion layer includes quantum dot units and a first retaining wall structure disposed between adjacent quantum dot units, wherein the quantum dot units are at least located in the pixel area, and the first retaining wall structure is located in the non-pixel area; Preferably, before forming the first conductive layer on one side of the substrate, the method further comprises: forming a third conductive layer on one side of the substrate, the third conductive layer comprising a plurality of third sub-electrodes arranged at intervals, the third sub-electrodes being located in the pixel region, wherein the first sub-electrode, the second sub-electrode and the third sub-electrode constitute a first electrode; Preferably, after the step of forming a light conversion layer on the side of the first encapsulation layer facing away from the substrate, the method further comprises: forming a second encapsulation layer on the side of the light conversion layer facing away from the substrate; Preferably, after the step of forming a second encapsulation layer on a side of the light conversion layer away from the substrate, the method further comprises: forming a color filter layer on a side of the second encapsulation layer away from the substrate; Preferably, before the step of forming a color filter layer on a side of the second encapsulation layer facing away from the substrate, the method further comprises: forming an inorganic layer on a side of the second encapsulation layer facing away from the substrate.

10. A display device, characterized in that: A display panel comprising any one of claims 1 to 6, or a display panel prepared by the method described in any one of claims 7 to 9.

Images