Light-emitting substrate, lighting device and display device

Abstract

The invention provides a light-emitting substrate, a lighting device and a display device, and relates to the technical field of display. The anode layer is arranged on one side of the substrate; the electroluminescent layer is arranged on one side, far away from the substrate, of the anode layer; the cathode layer is arranged on one side, far away from the substrate, of the electroluminescent layer; the first covering layer is arranged on one side, far away from the substrate, of the cathode layer; the second covering layer is arranged on one side, far away from the substrate, of the first covering layer; the refractive index of the second covering layer is greater than that of the first covering layer; the packaging structure layer comprises a first inorganic packaging layer and is arranged on one side, far away from the substrate, of the second covering layer; the first covering layer can improve the coupling efficiency between the light-emitting microcavity and the packaging structure layer, and the light-emitting efficiency of the light-emitting substrate is effectively improved.

Description

Technical Field

[0001] The present application relates to the field of display technology, and in particular to a light-emitting substrate, a lighting device and a display device. Background Art

[0002] A light-emitting device is a device that converts electrical energy into light energy. It excites fluorescent materials to produce light through high-frequency voltage applied to the electrode layers at both ends of the light-emitting layer. Due to its excellent electroluminescent properties, light-emitting substrates including multiple light-emitting devices are widely used in outdoor display devices such as smartphones and vehicles.

[0003] Among them, Organic Light-Emitting Diode (OLED), as the third-generation display technology, is not only lighter, thinner, has low energy consumption, high brightness, good luminous efficiency, and can display pure black, but can also be bent, thus bringing different visual impacts to people. It is widely used in today's curved screen TVs and mobile phones. Summary of the invention

[0004] The present application provides a light-emitting substrate, a lighting device and a display device, which are used to improve the problem of low light-emitting efficiency in the prior art.

[0005] According to one aspect of the present application, a light-emitting substrate is provided, and the light-emitting substrate includes:

[0006] substrate substrate;

[0007] An anode layer is arranged on one side of the substrate;

[0008] The electroluminescent layer is arranged on a side of the anode layer away from the substrate;

[0009] A cathode layer is arranged on a side of the electroluminescent layer away from the substrate;

[0010] A first covering layer is arranged on a side of the cathode layer away from the substrate;

[0011] A second covering layer is arranged on a side of the first covering layer away from the base substrate; the refractive index of the second covering layer is greater than the refractive index of the first covering layer;

[0012] The packaging structure layer includes a first inorganic packaging layer, which is arranged on a side of the second covering layer away from the substrate; wherein the first inorganic packaging layer includes at least one inorganic layer, and the refractive index of the inorganic layer closest to the second covering layer in the at least one inorganic layer is smaller than the refractive index of the second covering layer.

[0013] In a possible implementation, the light-emitting substrate further includes:

[0014] The third covering layer is disposed between the second covering layer and the packaging structure layer; wherein the refractive index of the third covering layer is smaller than the refractive index of the second covering layer, and the refractive index of the third covering layer is smaller than the refractive index of the inorganic layer closest to the second covering layer among the at least one inorganic layer.

[0015] In a possible implementation, the first covering layer includes a plurality of covering units distributed at intervals; the light-emitting substrate further includes an auxiliary electrode layer, which is disposed on a side of the cathode layer away from the base substrate and in contact with the cathode layer; the auxiliary electrode layer has a plurality of opening areas, and the covering units are located in the opening areas;

[0016] The electroluminescent layer comprises a plurality of light-emitting units, and an orthographic projection of the covering unit on the base substrate at least partially overlaps with an orthographic projection of at least one light-emitting unit on the base substrate.

[0017] In another possible implementation, each of the above-mentioned light-emitting units includes a plurality of light-emitting sub-units, and the covering unit includes a plurality of covering sub-units; the orthographic projection of each covering sub-unit on the base substrate overlaps with the orthographic projection of a light-emitting sub-unit on the base substrate.

[0018] In another possible implementation, each light-emitting unit includes a first light-emitting sub-unit, a second light-emitting sub-unit and a third light-emitting sub-unit, and the covering unit includes a first covering sub-unit and a second covering sub-unit; the orthographic projection of the first covering sub-unit on the substrate overlaps with the orthographic projection of the first light-emitting sub-unit and the second light-emitting sub-unit on the substrate; the orthographic projection of the second covering sub-unit on the substrate overlaps with the orthographic projection of the third light-emitting sub-unit on the substrate.

[0019] In another possible implementation, the first light-emitting subunit and the second light-emitting subunit are arranged along the first direction, the third light-emitting subunit is arranged on one side of the first light-emitting subunit and the second light-emitting subunit, and the area of ​​the first light-emitting subunit and the area of ​​the second light-emitting subunit are both smaller than the area of ​​the third light-emitting subunit;

[0020] The orthographic projections of the first light-emitting sub-unit and the second light-emitting sub-unit on the substrate are located within the orthographic projection range of the first covering sub-unit on the substrate, and the first covering sub-unit also includes a middle part located between the first light-emitting sub-unit and the second light-emitting sub-unit, and the width of the middle part in the first direction is greater than the target distance; wherein the target distance is the distance in the first direction between the orthographic projection edge of the first covering sub-unit on the substrate and the orthographic projection edge of the first light-emitting sub-unit on the substrate.

[0021] In yet another possible implementation, the orthographic projection of the light emitting unit on the base substrate is located within the orthographic projection range of the covering unit on the base substrate.

[0022] In another possible implementation, the light-emitting substrate further includes an undulating structure layer, and the undulating structure layer at least includes a second covering layer and a first inorganic encapsulation layer;

[0023] Along the direction perpendicular to the base substrate, the thickness of the covering unit is less than the thickness of the auxiliary electrode layer; the undulating structure layer includes a first protruding portion and a plurality of first recessed portions, the orthographic projection of the first recessed portion on the base substrate at least partially overlaps with the orthographic projection of the covering unit on the base substrate, and the orthographic projection of the first protruding portion on the base substrate at least partially overlaps with the orthographic projection of the auxiliary electrode layer on the base substrate.

[0024] In another possible implementation, the first recessed portion includes a first flat portion and a first climbing portion surrounding the first flat portion, and the distances between the first flat portions of different first recessed portions and the anode layer are substantially equal; along the direction away from the central axis of the first flat portion, the height of the first climbing portion is positively correlated with the first distance; wherein the first distance is the distance between the first climbing portion and the central axis of the first flat portion.

[0025] In another possible implementation, the light-emitting substrate further includes an undulating structure layer, and the undulating structure layer at least includes a second covering layer and a first inorganic encapsulation layer;

[0026] Along the direction perpendicular to the base substrate, the thickness of the covering unit is greater than the thickness of the auxiliary electrode layer; the undulating structure layer includes a second recessed portion and a plurality of second protruding portions, and the orthographic projection of the second protruding portion on the base substrate at least partially overlaps with the orthographic projection of the covering unit on the base substrate; the orthographic projection of the second recessed portion on the base substrate at least partially overlaps with the orthographic projection of the auxiliary electrode layer on the base substrate.

[0027] In another possible implementation, the second protrusion includes a second flat portion and a second climbing portion surrounding the second flat portion, and the distances between the second flat portions of different second protrusions and the anode layer are approximately equal; along the direction away from the central axis of the second flat portion, the height of the second climbing portion is negatively correlated with the second distance; wherein the second distance is the distance between the second climbing portion and the central axis of the second flat portion.

[0028] In another possible implementation, the at least one inorganic layer includes a first encapsulation sublayer, a second encapsulation sublayer and a third encapsulation sublayer;

[0029] Wherein, the first encapsulation sublayer is arranged on a side of the second covering layer away from the substrate;

[0030] The second encapsulation sublayer is arranged on a side of the first encapsulation sublayer away from the substrate;

[0031] The third encapsulation sublayer is arranged on a side of the second encapsulation sublayer away from the substrate;

[0032] The refractive index of the second encapsulation sublayer is greater than the refractive index of the first encapsulation sublayer, and the refractive index of the second encapsulation sublayer is greater than the refractive index of the third encapsulation sublayer.

[0033] In another possible implementation, the at least one inorganic layer further includes a fourth encapsulation sublayer, which is disposed between the first encapsulation sublayer and the second encapsulation sublayer; and a refractive index of the fourth encapsulation sublayer is greater than a refractive index of the second encapsulation sublayer.

[0034] In another possible implementation, the ratio of the refractive index of the second covering layer to the refractive index of the first covering layer is K1, 1.18<K1<1.93.

[0035] In another possible implementation, the refractive index of the first covering layer is N1, 1.35≤N1≤1.7; the refractive index of the second covering layer is N2, 2.0≤N2≤2.6.

[0036] In another possible implementation, the ratio of the refractive index of the second cover layer to the refractive index of the third cover layer is K2, 1.25≤K2≤2; the ratio of the refractive index of the first encapsulation sublayer to the refractive index of the third cover layer is K3, 1<K3<1.24.

[0037] In another possible implementation, the ratio of the refractive index of the second encapsulation sublayer to the refractive index of the first encapsulation sublayer is K4, 1<K4<1.47; the ratio of the refractive index of the second encapsulation sublayer to the refractive index of the third encapsulation sublayer is K5, 1<K5<1.27.

[0038] In another possible implementation, the ratio of the refractive index of the fourth encapsulation sublayer to the refractive index of the second encapsulation sublayer is K6, 1<K6≤1.25.

[0039] According to another aspect of the present application, a lighting device is provided. The lighting device includes the light-emitting substrate shown in the first aspect of the present application.

[0040] According to another aspect of the present application, a display device is provided. The display device includes the light-emitting substrate shown in the first aspect of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, a brief introduction will be given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0042] Figure 1-1A schematic diagram of total reflection occurring in a light-emitting substrate provided in an embodiment of the present application;

[0043] Figure 1-2 A schematic diagram of the radiation direction of waveguide light in a light-emitting substrate provided in an embodiment of the present application;

[0044] Figure 2 A cross-sectional structural diagram of a light-emitting substrate provided in an embodiment of the present application;

[0045] Figure 3 A cross-sectional structural diagram of another light-emitting substrate provided in an embodiment of the present application;

[0046] Figure 4 A cross-sectional structural diagram of another light-emitting substrate provided in an embodiment of the present application;

[0047] Figure 5 A cross-sectional structural diagram of another light-emitting substrate provided in an embodiment of the present application;

[0048] Figure 6 A cross-sectional structural diagram of a first inorganic encapsulation layer in a light-emitting substrate provided in an embodiment of the present application;

[0049] Figure 7 A cross-sectional structural diagram of another light-emitting substrate provided in an embodiment of the present application;

[0050] Figure 8 A cross-sectional structural diagram of another light-emitting substrate provided in an embodiment of the present application;

[0051] Fig. 9 A cross-sectional structural diagram of another light-emitting substrate provided in an embodiment of the present application;

[0052] Figure 10-1 A top view of a first covering layer in a light-emitting substrate provided in an embodiment of the present application;

[0053] Figure 10-2 A top view of another first covering layer in the light-emitting substrate provided in an embodiment of the present application;

[0054] Figure 10-3 A top view of another first covering layer in the light-emitting substrate provided in an embodiment of the present application;

[0055] Figure 11-1 A schematic diagram of the arrangement of light-emitting subunits in a light-emitting substrate provided in an embodiment of the present application;

[0056] Figure 11-2 A schematic diagram of another arrangement of light-emitting subunits in a light-emitting substrate provided in an embodiment of the present application;

[0057] Figure 11-3 A schematic diagram of another arrangement of light-emitting subunits in a light-emitting substrate provided in an embodiment of the present application;

[0058] Figure 11-4 A schematic diagram of another arrangement of light-emitting subunits in a light-emitting substrate provided in an embodiment of the present application;

[0059] Fig.12 A sampling diagram for the cover layer in different samples of the light-emitting substrate provided in the embodiment of the present application;

[0060] Fig.13 A cross-sectional structural diagram of a light-emitting substrate with an undulating structural layer provided in an embodiment of the present application;

[0061] Fig.14 A cross-sectional structural diagram of another light-emitting substrate with an undulating structure layer provided in an embodiment of the present application. DETAILED DESCRIPTION

[0062] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the present disclosure. In addition, in the following description, descriptions of well-known structures and technologies are omitted to avoid unnecessary confusion of the concepts of the present disclosure.

[0063] Various structural schematic diagrams according to embodiments of the present disclosure are shown in the accompanying drawings. These figures are not drawn to scale, and some details are magnified and some details may be omitted for the purpose of clear expression. The shapes of various regions and layers shown in the figures and the relative sizes and positional relationships therebetween are only exemplary, and may deviate in practice due to manufacturing tolerances or technical limitations, and those skilled in the art may further design regions / layers with different shapes, sizes, and relative positions according to actual needs.

[0064] In the context of the present disclosure, when a layer / element is referred to as being "on" another layer / element, the layer / element may be directly on the other layer / element or an intervening layer / element may exist therebetween. In addition, if a layer / element is "on" another layer / element in one orientation, the layer / element may be "below" the other layer / element when the orientation is reversed.

[0065] The luminous principle of the luminous substrate is as follows: Figure 1-1As shown, electrons and holes are respectively injected from the cathode layer 104 and the anode layer 102 of the light-emitting substrate into the electroluminescent layer 103, where they are recombined and the electrical energy is converted into light energy in the form of luminescent radiation and emitted. Among them, the inventors found that a CPL (Capping Layer) 1052 can be set on the side of the cathode layer 104 away from the base substrate 101. The CPL 1052 layer has characteristics such as high refractive index and low absorption coefficient. The CPL layer 1052 can be set above the cathode layer 104 by evaporation or the like, and a packaging structure layer 110 (including a first inorganic packaging layer 106, an organic packaging layer 107 and a second inorganic packaging layer 108) is set on the side of the CPL layer 1052 away from the base substrate 101. The above-mentioned CPL layer 1052 and the packaging structure layer 110 are strong reflective film layer structures with different refractive indices and periodically stacked on each other, so that the cathode layer 104 covered with the CPL layer 1052 has good transmittance, thereby improving the transmittance of the light-emitting substrate, and improving the optical properties and luminous efficiency of the light-emitting substrate. However, there is a resonance mismatch between the light-emitting microcavity 108 of the light-emitting substrate and the strong reflective film layer structure, and the plasma loss in the cathode layer 104 and the nearby film layers is too large; at the same time, too much waveguide light will be localized in the high-refractive index CPL layer 1052. When the incident angle is greater than the critical value, the light will be totally reflected from the optically dense medium CPL layer 1052 to the optically sparse medium first inorganic encapsulation layer 106. The above situations will increase the power consumption of the light-emitting substrate and reduce the luminous efficiency.

[0066] Based on the above technical problems, some embodiments of the present application can sequentially arrange an anode layer, an electroluminescent layer and a cathode layer on one side of the substrate, and then arrange a first covering layer on the side of the cathode layer away from the substrate, and sequentially arrange a second covering layer and a packaging structure layer on the side of the first covering layer away from the substrate; wherein the packaging structure layer may include at least one inorganic layer, the refractive index of the second covering layer is greater than the refractive index of the first covering layer, and the refractive index of the second covering layer is also greater than the refractive index of the inorganic layer closest to the second covering layer in at least one inorganic layer, and the above second covering layer and the packaging structure layer can constitute a strong reflective film layer structure, when light passes through the above film layers with different refractive indices, the light reflected back by each layer constructively interferes due to the change in phase angle, which can reduce reflection of light within a certain wavelength range and increase the amount of light transmitted. At the same time, the arrangement of the first covering layer in the present application can effectively increase the spacing distance between the light-emitting microcavity and the packaging structure layer, improve the coupling efficiency between the light-emitting microcavity and the packaging structure layer, eliminate the resonance mismatch between the light-emitting microcavity and the strong reflective film layer structure, and effectively improve the luminous efficiency of the light-emitting substrate.

[0067] The following is a detailed description of the technical solution of the present application and how the technical solution of the present application solves the above-mentioned technical problems with specific embodiments. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments. The embodiments of the present application will be described below in conjunction with the accompanying drawings.

[0068] In an embodiment of the present application, a light-emitting substrate is provided, such as Figure 2 As shown, the light-emitting substrate may include a base substrate 210 , an anode layer 220 , an electroluminescent layer 230 , a cathode layer 240 , a first covering layer 251 , a second covering layer 252 and a packaging structure layer 260 which are stacked in sequence.

[0069] The substrate 210 can be either rigid or flexible. When the substrate is a rigid substrate, the material forming the rigid substrate can be glass, and when the substrate is a flexible substrate, the material forming the flexible substrate can be PI (polyimide), PET (polyethylene terephthalate), ultra-thin glass, etc. The substrate 210 is used to support and protect the anode layer 220, the electroluminescent layer 230, the cathode layer 240, the first covering layer 251, the second covering layer 252, and the packaging structure layer 260 that are stacked in sequence.

[0070] The anode layer 220 is disposed on one side of the base substrate 210. The material of the anode layer may include a material having a high work function. In some embodiments, the anode layer may be a multilayer composite structure including a transparent conductive oxide layer and a metal layer. For example, the material of the transparent conductive oxide layer may be any one of ITO (Indium tin oxide) and IZO (Indium zinc oxide), and the material of the metal layer may be any one or more of aluminum (Al), silver (Ag), titanium (Ti), molybdenum (Mo), etc. For example, the structure of the anode layer may be ITO / Ag / ITO, IZO / Ag / IZO or ITO / Ag / ITO / Al, etc. Of course, in other embodiments, the anode layer may also be a single-layer structure, such as the material of the single-layer structure may be any one of aluminum (Al), silver (Ag), titanium (Ti), and molybdenum (Mo).

[0071] The electroluminescent layer 230 is disposed on a side of the anode layer 220 away from the base substrate 210. Figure 3As shown, the electroluminescent layer 230 may include a hole injection layer 231, a hole transport layer 232, a light-emitting layer 233, a hole blocking layer 234, an electron transport layer 235, and an electron injection layer 236 which are stacked in sequence. In some embodiments, the light-emitting layer 233 may include a plurality of light-emitting subunits 2331, and the specific light-emitting colors of the light-emitting subunits are not limited here. Exemplarily, the plurality of light-emitting subunits may include light-emitting subunits of a plurality of different light-emitting colors, such as: a light-emitting subunit with a red light-emitting color, a light-emitting subunit with a green light-emitting color, and a light-emitting subunit with a blue light-emitting color. The light-emitting subunit of each color includes a light-emitting material that can emit light of a corresponding color. Of course, in other embodiments, the light-emitting color of the light-emitting layer may also be one, such as: the light-emitting color is blue or white, etc., which is determined according to the needs of the actual application scenario, and this embodiment does not limit this.

[0072] Optionally, the light-emitting layer 1033 may also include a light-emitting material layer 10332; the light-emitting material layer may mainly include a Prime material (light-emitting functional material), a Host material (light-emitting main material) and a Dopant material (doping material), wherein the Prime material blocks the transmission of electrons and holes and improves the luminous efficiency of the light-emitting layer; the Host material efficiently transfers energy to the Dopant material according to the energy requirements of different colors, thereby improving the luminous ability of the dopant; the Dopant material plays a role in efficient luminescence.

[0073] Optionally, when the electroluminescent layer has a light-emitting layer of one color, the light-emitting substrate can be applied to a lighting device; when the electroluminescent layer includes a light-emitting subunit with a red light-emitting color, a light-emitting subunit with a green light-emitting color, and a subunit with a blue light-emitting color, the light-emitting substrate can be applied to a display device. It should be noted that when the light-emitting substrate is used as a backlight, it can also be used as a display after a color filter substrate is provided.

[0074] The cathode layer 104 is disposed on a side of the electroluminescent layer 103 away from the base substrate 101 .

[0075] For example, the cathode layer can be made of metal material. When current flows in the light-emitting substrate, the cathode layer will inject electrons into the circuit. The lower the metal work function of the cathode material, the easier it is to inject electrons and the higher the luminous efficiency.

[0076] The thickness of the cathode layer is D, 6nm≤D≤16nm, for example, the thickness of the cathode layer can be 6nm, or 10nm or 15nm. Since there are many free electrons in the metal material of the cathode layer, irradiating the metal surface easily causes electron oscillation, the embodiment of the present application reduces the thickness of the cathode layer, which can effectively reduce the plasma loss in the cathode layer and the film layer near it in the light-emitting substrate, and further improve the light-emitting efficiency.

[0077] The first covering layer 251 is disposed on a side of the cathode layer 240 away from the base substrate 210 ; the second covering layer 252 is disposed on a side of the first covering layer 251 away from the base substrate 210 ; the refractive index of the second covering layer 252 is greater than that of the first covering layer 251 .

[0078] Optionally, the ratio of the refractive index of the second covering layer to the refractive index of the first covering layer may be K1, 1.18<K1<1.93; and the thickness of the first covering layer is smaller than the thickness of the second covering layer.

[0079] Specifically, the refractive index of the first covering layer may be N1, 1.35≤N1≤1.7, for example, N1 may be 1.4, 1.5 or 1.6; the refractive index of the second covering layer may be N2, 2.0≤N2≤2.6, for example, N2 may be 2.0, 2.1 or 2.5; the thickness of the first covering layer is D3, 10nm≤D3≤40nm, for example, D3 may be 10nm, 20nm or 30nm; the thickness of the second covering layer is D4, 50nm≤D4≤70nm, for example, D4 ​​may be 50nm, 60nm or 70nm. The rates of change of the refractive index of the first covering layer and the second covering layer with wavelength are both less than 0.1, and the extinction coefficients of the first covering layer and the second covering layer are both less than 0.01.

[0080] The packaging structure layer 260, such as Figure 4 As shown, a first inorganic encapsulation layer 261 may be included, which is disposed on a side of the second covering layer 252 away from the base substrate 210 .

[0081] The first inorganic encapsulation layer includes at least one inorganic layer, and the refractive index of the inorganic layer closest to the second covering layer in the at least one inorganic layer is smaller than the refractive index of the second covering layer.

[0082] Optionally, the encapsulation structure layer may further include an organic encapsulation layer 262 and a second inorganic encapsulation layer 263 ; wherein the organic encapsulation layer 262 is arranged on the side of the first inorganic encapsulation layer 261 away from the base substrate 210 , and the second inorganic encapsulation layer 263 is arranged on the side of the organic encapsulation layer 262 away from the base substrate 210 .

[0083] The organic encapsulation layer is configured to improve the light extraction rate of the light-emitting layer and release the internal stress in the first inorganic encapsulation layer and the second inorganic encapsulation layer. The organic encapsulation layer can be a single film layer structure or a multi-film layer structure. For example, it can be a single film layer structure of SiCxNy (silicon carbon nitride), or a single film layer structure of SiOCxNy (silicon oxycarbon nitride); or it can also be a multi-film layer structure composed of a SiNx (silicon nitride) layer, a SiCN (silicon carbon nitride) layer and a SiO2 (silicon dioxide) layer, or a multi-film layer structure composed of a SiNx layer, an AL2O3 (aluminum oxide) layer, a Parylene (Parylene, a new type of thermoplastic plastic) layer, and an organic layer.

[0084] Specifically, the thickness of the organic encapsulation layer and the thickness of the second inorganic encapsulation layer are both between 380 nm and 780 nm.

[0085] In the embodiment of the present application, a first covering layer is arranged on a side of the cathode layer away from the substrate, and a second covering layer and a packaging structure layer are arranged in sequence on a side of the first covering layer away from the substrate; wherein the packaging structure layer may include at least one inorganic layer, the refractive index of the second covering layer is greater than the refractive index of the first covering layer, and the refractive index of the second covering layer is also greater than the refractive index of the inorganic layer closest to the second covering layer among the at least one inorganic layer, and the above-mentioned second covering layer and the packaging structure layer can constitute a strong reflection film layer structure, when light passes through the above-mentioned film layers with different refractive indices, the light reflected back by each layer constructively interferes due to the change in phase angle, which can reduce reflection of light within a certain wavelength range and increase the amount of light transmitted. At the same time, the setting of the first covering layer in the present application can effectively increase the spacing distance between the light-emitting microcavity and the packaging structure layer, improve the coupling efficiency between the light-emitting microcavity and the packaging structure layer, eliminate the resonance mismatch between the light-emitting microcavity and the strong reflection film layer structure, and effectively improve the luminous efficiency of the light-emitting substrate.

[0086] A possible implementation method is provided in the embodiment of the present application, such as Figure 5 As shown, the above-mentioned light-emitting substrate may further include: a third covering layer 253, which is arranged between the second covering layer 252 and the encapsulation structure layer 260. The refractive index of the third covering layer is less than the refractive index of the second covering layer, and the refractive index of the third covering layer is less than the refractive index of the inorganic layer closest to the second covering layer in the at least one inorganic layer. At the same time, the thickness of the third covering layer is less than the thickness of the second covering layer, and the thickness of the third covering layer is less than the thickness of the inorganic layer closest to the second covering layer in the at least one inorganic layer.

[0087] Optionally, the ratio of the refractive index of the second covering layer to the refractive index of the third covering layer is K2, 1.25≤K2≤2; the ratio of the refractive index of the first encapsulation sublayer to the refractive index of the third covering layer is K3, 1<K3<1.24.

[0088] Specifically, the refractive index of the third covering layer is N3, 1.3≤N3≤1.6; the thickness of the third covering layer is D5, 10nm≤D5≤30nm. For example, N3 can be 1.3, 1.5 or 1.6, and D5 can be 10nm, 20nm or 30nm.

[0089] In the embodiment of the present application, since the high-refractive-index second covering layer easily localizes waveguide light, by arranging the first covering layer and the third covering layer with relatively low refractive index and low thickness on both sides thereof, the transmission direction of light can be improved, the waveguide light can be reduced, the light extraction rate can be enhanced, and the white light efficiency of the light-emitting substrate can be effectively improved.

[0090] Optionally, the materials of the first covering layer and the third covering layer may include low refractive index organic materials, such as 4-fluoro-N-(3-{[(4-fluorophenyl)carbonyl]amino}tricyclo[3.3.1.13,7]dec-7-yl)benzamide, which has a structure shown in general formula (1):

[0091]

[0092] The above organic material may also include N-[3-(phenylcarbonylamino)tricyclo[3.3.1.13,7]dec-7-yl]benzamide, which has a structure shown in general formula (2):

[0093]

[0094] The organic material may also include N-{2-[(tricyclo[3.3.1.13,7]dec-1-ylcarbonyl)amino]tricyclo[3.3.1.13,7]dec-2-yl}tricyclo[3.3.1.13,7]decane-1-carboxamide, which has a structure shown in general formula (3):

[0095]

[0096] In the present application embodiment, Figure 1-2 As shown, on the one hand, the newly added first covering layer and the third covering layer can effectively increase the distance between the light-emitting microcavity 108 and the strong reflective film layer structure, and further improve the resonance mismatch; on the other hand, the thickness of the third covering layer 1053 is much smaller than the wavelength of the incident light, so the evanescent wave generated by the total reflection at the interface between the high-refractive index second covering layer 1052 and the low-refractive index third covering layer 1053 can penetrate the third covering layer 1053. At the same time, because the refractive index of the third covering layer is smaller than the refractive index of the inorganic layer closest to the second covering layer in at least one inorganic layer, total reflection will not occur, so that the radiation direction of the originally localized waveguide light is changed, and the light extraction efficiency of the light-emitting substrate is further improved.

[0097] Table 1

[0098]

[0099]

[0100] As shown in Table 1, the Figure 1-1 , Figure 4 and Figure 5 The covering layer parameters in each light-emitting substrate shown in, Figure 1-1 The light-emitting substrate is provided with a second covering layer with a thickness of 80 nm. Figure 4 The light emitting substrate is provided with a first covering layer having a thickness of 23 nm and a second covering layer having a thickness of 60 nm. Figure 5 The light-emitting substrate in the embodiment is provided with a first covering layer with a thickness of 23 nm, a second covering layer with a thickness of 60 nm, and a third covering layer with a thickness of 23 nm. When other structures of the light-emitting substrate are the same, it can be known from the comparison of simulation experimental data that: Figure 4 The white light efficiency of the luminous substrate is relative to Figure 1-1 The white light efficiency of the medium-emitting substrate has been increased by 3.8%. Figure 5 The white light efficiency of the luminous substrate is relative to Figure 1-1 The white light efficiency of the medium-emitting substrate has been increased by 4.2%; at the same time, Figure 4 and Figure 5 The brightness attenuation rate of the luminous substrate in Figure 1-1 The brightness attenuation rate of the light-emitting substrate in the experiment has decreased.

[0101] A possible implementation method is provided in the embodiment of the present application, such as Figure 6 As shown, the at least one inorganic layer includes a first encapsulation sublayer 2611, a second encapsulation sublayer 2612 and a third encapsulation sublayer 2613. The first encapsulation sublayer 2611 is disposed on a side of the second cover layer 252 away from the base substrate 210; the second encapsulation sublayer 2612 is disposed on a side of the first encapsulation sublayer 2611 away from the base substrate 210; the third encapsulation sublayer 2613 is disposed on a side of the second encapsulation sublayer 2612 away from the base substrate 210; the refractive index of the second encapsulation sublayer is greater than the refractive index of the first encapsulation sublayer, and the refractive index of the second encapsulation sublayer is greater than the refractive index of the third encapsulation sublayer.

[0102] Optionally, the thickness of the second encapsulation sublayer is greater than the thickness of the first encapsulation sublayer, and the thickness of the second encapsulation sublayer is greater than the thickness of the third encapsulation sublayer.

[0103] A possible implementation method is provided in an embodiment of the present application, where the ratio of the refractive index of the second encapsulation sublayer to the refractive index of the first encapsulation sublayer is K4, 1<K4<1.47; the ratio of the refractive index of the second encapsulation sublayer to the refractive index of the third encapsulation sublayer is K5, 1<K5<1.27.

[0104] A possible implementation method is provided in an embodiment of the present application. The refractive index of the above-mentioned first encapsulation sublayer may be N4, 1.3≤N4≤1.6, and the thickness may be D6, 50nm≤D6≤140nm; the refractive index of the second encapsulation sublayer may be N5, 1.6≤N5≤1.9, and the thickness may be D7, 600nm≤D7≤1000nm; the refractive index of the third encapsulation sublayer may be N6, 1.5≤N6≤1.7, and the thickness may be D8, 50nm≤D8≤150nm. For example, when N5 is 1.6 and D7 is 600nm, N4 can be 1.3, D6 can be 50nm, N6 can be 1.5, and D8 can be 50nm; when N5 is 1.7 and D7 is 800nm, N4 can be 1.4, D6 can be 80nm, N6 can be 1.55, and D8 can be 70nm; when N5 is 1.9 and D7 is 1000nm, N4 can be 1.6, D6 can be 140nm, N6 can be 1.7, and D8 can be 150nm.

[0105] In the embodiment of the present application, the second encapsulation sublayer is relatively thick, which can provide effective protection for the light-emitting device and ensure the reliability of the light-emitting substrate; at the same time, the thickness of the first encapsulation sublayer and the third encapsulation sublayer is relatively small and the refractive index is relatively low, which can further correct the luminous efficiency and improve the light output rate of the light-emitting substrate.

[0106] like Figure 7 As shown, the first inorganic encapsulation layer 261 may include a first encapsulation sublayer 2611 with a low refractive index, a second encapsulation sublayer 2612 with a high refractive index, and a third encapsulation sublayer 2613 with a low refractive index. The at least one inorganic layer constitutes a strong reflective film layer structure. The embodiment of the present application stacks inorganic layers of different refractive indices interactively and periodically. When light passes through these inorganic layers with different refractive indices, the light reflected back from each layer constructively interferes due to the change in phase angle, and then combines with each other to obtain strongly reflected light. The at least one inorganic layer can improve the light output rate and further enhance the luminous efficiency of the light-emitting substrate.

[0107] A possible implementation method is provided in an embodiment of the present application, wherein the at least one inorganic layer further includes a fourth encapsulation sublayer, and the fourth encapsulation sublayer is arranged between the first encapsulation sublayer and the second encapsulation sublayer; the refractive index of the fourth encapsulation sublayer is greater than the refractive index of the second encapsulation sublayer.

[0108] A possible implementation method is provided in an embodiment of the present application, where the ratio of the refractive index of the fourth encapsulation sublayer to the refractive index of the second encapsulation sublayer is K6, and 1<K6≤1.25.

[0109] The present application provides a possible implementation method, wherein the refractive index of the fourth encapsulation sublayer is N7, 1.75≤N7≤2, and the thickness is D9, 40nm≤D9≤70nm. For example, N7 can be 1.75, 1.9 or 2; D9 can be 40nm, 55nm or 70nm.

[0110] like Figure 8 As shown, the first inorganic encapsulation layer 261 may include a first encapsulation sublayer 2611 with a high refractive index, a fourth encapsulation sublayer 2614 with a low refractive index, a second encapsulation sublayer 2612 with a high refractive index, and a third encapsulation sublayer 2613 with a low refractive index in sequence. By adding a fourth encapsulation sublayer 2614 between the first encapsulation sublayer 2611 and the second encapsulation sublayer 2612, the light transmittance of the multiple film layers is further enhanced, so that the luminous efficiency of the light-emitting substrate is further improved.

[0111] A possible implementation method is provided in the embodiment of the present application, such as Fig. 9 As shown, the first covering layer 251 includes a plurality of covering units 2511 distributed at intervals; the light-emitting substrate further includes an auxiliary electrode layer 2512, which is arranged on a side of the cathode layer 240 away from the base substrate 210 and in contact with the cathode layer 240; the auxiliary electrode layer 2512 has a plurality of opening areas, and the covering units 2511 are located in the opening areas;

[0112] The electroluminescent layer comprises a plurality of light-emitting units, and an orthographic projection of the covering unit on the base substrate at least partially overlaps with an orthographic projection of at least one light-emitting unit on the base substrate.

[0113] In some embodiments, the light-emitting unit may include a plurality of light-emitting sub-units, and the covering unit may include a plurality of covering sub-units; the orthographic projection of each covering sub-unit on the base substrate overlaps with the orthographic projection of a light-emitting sub-unit on the base substrate.

[0114] In some other embodiments, the orthographic projection of the light emitting unit on the base substrate may be located within the orthographic projection range of the covering unit on the base substrate.

[0115] In some further embodiments, each light-emitting unit may include a first light-emitting sub-unit, a second light-emitting sub-unit and a third light-emitting sub-unit, and the covering unit may include a first covering sub-unit and a second covering sub-unit; the orthographic projection of the first covering sub-unit on the substrate overlaps with the orthographic projection of the first light-emitting sub-unit and the second light-emitting sub-unit on the substrate; the orthographic projection of the second covering sub-unit on the substrate overlaps with the orthographic projection of the third light-emitting sub-unit on the substrate.

[0116] For example, each light-emitting unit may include at least one light-emitting subunit emitting red light, at least one light-emitting subunit emitting green light, and at least one light-emitting subunit emitting blue light; and each covering unit may correspond to at least one light-emitting subunit. Figure 10-1 As shown, each light-emitting unit p may include a first light-emitting subunit p1, a second light-emitting subunit p2 and a third light-emitting subunit p3; the first light-emitting subunit p1 and the second light-emitting subunit p2 are arranged in the first direction, i.e., the Y axis, and the third light-emitting subunit p3 is located on one side of the first light-emitting subunit p1 and the second light-emitting subunit p2. For example, the first light-emitting subunit may be a red light-emitting subunit, the second light-emitting subunit may be a green light-emitting subunit, and the third light-emitting subunit may be a blue light-emitting subunit, i.e., an RGB pixel arrangement is adopted.

[0117] Optionally, the auxiliary electrode layer 2512 may be a mesh structure layer having a plurality of opening regions, a covering unit may be disposed in each opening region, and each covering unit may correspond to a light-emitting unit p.

[0118] like Figure 10-1 The figure shows a top view of the auxiliary electrode layer, and the above-mentioned covering unit may include a first covering subunit f1, a second covering subunit f2 and a third covering subunit f3. The orthographic projection of the first light-emitting subunit p1 on the substrate is located within the orthographic projection range of the first covering subunit f1 on the substrate; the orthographic projection of the second light-emitting subunit p2 on the substrate is located within the orthographic projection range of the second covering subunit f2 on the substrate; the orthographic projection of the third light-emitting subunit p3 on the substrate is located within the orthographic projection range of the third covering subunit f3 on the substrate.

[0119] like Figure 10-2Another top view of the auxiliary electrode layer is shown, and the above-mentioned covering unit may include a first covering subunit f1 and a second covering subunit f2. The orthographic projections of the first light-emitting subunit p1 and the second light-emitting subunit p2 on the substrate may be located within the orthographic projection range of the first covering subunit f1 on the substrate; the orthographic projection of the third light-emitting subunit p3 on the substrate is located within the orthographic projection range of the second covering subunit f2 on the substrate; the first covering subunit f1 also includes a middle portion located between the first light-emitting subunit and the second light-emitting subunit, and the width of the middle portion in the first direction, i.e., the y-axis, is greater than the target distance; wherein the target distance is the distance in the first direction between the orthographic projection edge of the first covering subunit on the substrate and the orthographic projection edge of the first light-emitting subunit on the substrate.

[0120] like Figure 10-3 Another top view of the auxiliary electrode layer is shown. Each covering unit 2511 may correspond to three light-emitting sub-units, that is, the orthographic projection of each light-emitting unit on the base substrate is located within the orthographic projection range of a covering unit on the base substrate.

[0121] Figure 11-1 A schematic diagram of the arrangement of the light-emitting subunits in some embodiments of the present application is shown. Each light-emitting subunit P may include: a first light-emitting subunit p1, two second light-emitting subunits p2 and a third light-emitting subunit p3. The first light-emitting subunit p1 and the third light-emitting subunit p3 may be arranged along the X-axis direction, the two second light-emitting subunits p2 may be arranged along the Y-axis direction, the two second light-emitting subunits p2 are located on one side of the third light-emitting subunit p3, and the first light-emitting subunit p1 is located on the other side of the third light-emitting subunit p3. For example, the first light-emitting subunit p1 may be a red light-emitting subunit, the second light-emitting subunit p2 may be a green light-emitting subunit, and the third light-emitting subunit p3 may be a blue light-emitting subunit, that is, a GGRB pixel arrangement is adopted.

[0122] Optionally, the auxiliary electrode layer may be a mesh structure layer having a plurality of opening areas, and a covering unit may be disposed in each opening area; wherein the covering unit may include a first covering subunit, a second covering subunit, a third covering subunit, and a fourth covering subunit. The orthographic projection of the first light-emitting subunit on the base substrate may be located within the orthographic projection range of the first covering subunit on the base substrate, the orthographic projections of the two second light-emitting subunits on the base substrate may be located respectively within the orthographic projection ranges of the second covering subunit and the third covering subunit on the base substrate, and the orthographic projection of the third light-emitting subunit on the base substrate may be located within the orthographic projection range of the fourth covering subunit on the base substrate.

[0123] Alternatively, the above-mentioned covering unit may include a first covering subunit, a second covering subunit and a third covering subunit. The orthographic projection of the first light-emitting subunit on the base substrate may be located within the orthographic projection range of the first covering subunit on the base substrate, the orthographic projections of the two second light-emitting subunits on the base substrate may be located within the orthographic projection range of the second covering subunit on the base substrate, and the orthographic projection of the third light-emitting subunit on the base substrate may be located within the orthographic projection range of the third covering subunit on the base substrate.

[0124] Alternatively, the covering unit may include a first covering subunit and a second covering subunit. The orthographic projections of the first light-emitting subunit and the third light-emitting subunit on the base substrate may be located within the orthographic projection range of the first covering subunit on the base substrate, and the orthographic projections of the two second light-emitting subunits on the base substrate may be located within the orthographic projection range of the second covering subunit on the base substrate.

[0125] Alternatively, the orthographic projection of each light emitting unit on the base substrate may be located within the orthographic projection range of a covering sub-unit on the base substrate.

[0126] Figure 11-2 A schematic diagram of the arrangement of the light-emitting subunits in some embodiments of the present application is shown. Each light-emitting subunit P may include: a first light-emitting subunit p1, two second light-emitting subunits p2 and a third light-emitting subunit p3, all of which are rectangular; a first light-emitting subunit p1, two second light-emitting subunits p2 and a third light-emitting subunit p3 are respectively located at the four vertices of a virtual rectangle, and the two second light-emitting subunits p2 can be arranged along the x-axis direction and are respectively located at the opposite vertices of the virtual rectangle. For example, the first light-emitting subunit p1 can be a red light-emitting subunit, the second light-emitting subunit p2 can be a green light-emitting subunit, and the third light-emitting subunit p3 can be a blue light-emitting subunit, that is, a GGRB pixel arrangement is adopted.

[0127] Optionally, the auxiliary electrode layer may be a mesh structure layer having a plurality of opening areas, and a covering unit may be disposed in each opening area; wherein the covering unit may include a first covering subunit, a second covering subunit, a third covering subunit, and a fourth covering subunit. The orthographic projection of the first light-emitting subunit on the base substrate may be located within the orthographic projection range of the first covering subunit on the base substrate, the orthographic projections of the two second light-emitting subunits on the base substrate may be located respectively within the orthographic projection ranges of the second covering subunit and the third covering subunit on the base substrate, and the orthographic projection of the third light-emitting subunit on the base substrate may be located within the orthographic projection range of the fourth covering subunit on the base substrate.

[0128] Alternatively, the above-mentioned covering unit may include a first covering subunit, a second covering subunit and a third covering subunit. The orthographic projection of the first light-emitting subunit on the base substrate may be located within the orthographic projection range of the first covering subunit on the base substrate, the orthographic projections of the two second light-emitting subunits on the base substrate may be located within the orthographic projection range of the second covering subunit on the base substrate, and the orthographic projection of the third light-emitting subunit on the base substrate may be located within the orthographic projection range of the third covering subunit on the base substrate.

[0129] Alternatively, the covering unit may include a first covering subunit and a second covering subunit. The orthographic projections of the first light-emitting subunit and the third light-emitting subunit on the base substrate may be located within the orthographic projection range of the first covering subunit on the base substrate, and the orthographic projections of the two second light-emitting subunits on the base substrate may be located within the orthographic projection range of the second covering subunit on the base substrate.

[0130] Alternatively, the orthographic projection of each light emitting unit on the base substrate may be located within the orthographic projection range of a covering sub-unit on the base substrate.

[0131] Figure 11-3 Schematic diagrams of the arrangement of light-emitting subunits in other embodiments of the present application are shown. Each pixel unit P may also include: a first light-emitting subunit p1, a second light-emitting subunit p2 and a third light-emitting subunit p3, and the above three light-emitting subunits are arranged alternately along the x-axis; the first light-emitting subunit p1 may be a parallelogram, the second light-emitting subunit p2 and the third light-emitting subunit p3 may be hexagons, and the third light-emitting subunit P3 has the largest area; for example, the first light-emitting subunit p1 may be a red light-emitting subunit, the second light-emitting subunit p2 may be a green light-emitting subunit, and the third light-emitting subunit p3 may be a blue light-emitting subunit, that is, an RGB pixel arrangement is adopted.

[0132] Optionally, the auxiliary electrode layer may be a mesh structure layer having a plurality of opening areas, and a covering unit may be provided in each opening area; wherein the covering unit may include a first covering subunit, a second covering subunit, a third covering subunit, and a fourth covering subunit. The orthographic projection of the first light-emitting subunit on the base substrate may be located within the orthographic projection range of the first covering subunit on the base substrate, the orthographic projection of the second light-emitting subunit on the base substrate may be located within the orthographic projection range of the second covering subunit on the base substrate, and the orthographic projection of the third light-emitting subunit on the base substrate may be located within the orthographic projection range of the third covering subunit on the base substrate.

[0133] Alternatively, the covering unit may include a first covering subunit and a second covering subunit. The orthographic projections of the first light-emitting subunit and the second light-emitting subunit on the base substrate may be located within the orthographic projection range of the first covering subunit on the base substrate, and the orthographic projection of the third light-emitting subunit on the base substrate may be located within the orthographic projection range of the second covering subunit on the base substrate.

[0134] Alternatively, the orthographic projection of each light emitting unit on the base substrate may be located within the orthographic projection range of a covering sub-unit on the base substrate.

[0135] Figure 11-4 Schematic diagrams of the arrangement of light-emitting subunits in other embodiments of the present application are shown. Each pixel unit P may also include: a first light-emitting subunit p1, a second light-emitting subunit p2 and a third light-emitting subunit p3, the first light-emitting subunit p1, the second light-emitting subunit p2 and the third light-emitting subunit p3 are all long strips and arranged in sequence along the X-axis direction. For example, the first light-emitting subunit p1 may be a red light-emitting subunit, the second light-emitting subunit p2 may be a green light-emitting subunit, and the third light-emitting subunit p3 may be a blue light-emitting subunit, that is, an RGB pixel arrangement is adopted.

[0136] Optionally, the auxiliary electrode layer may be a mesh structure layer having a plurality of opening areas, and a covering unit may be provided in each opening area; wherein the covering unit may include a first covering subunit, a second covering subunit, a third covering subunit, and a fourth covering subunit. The orthographic projection of the first light-emitting subunit on the base substrate may be located within the orthographic projection range of the first covering subunit on the base substrate, the orthographic projection of the second light-emitting subunit on the base substrate may be located within the orthographic projection range of the second covering subunit on the base substrate, and the orthographic projection of the third light-emitting subunit on the base substrate may be located within the orthographic projection range of the third covering subunit on the base substrate.

[0137] Alternatively, the covering unit may include a first covering subunit and a second covering subunit. The orthographic projections of the first light-emitting subunit and the second light-emitting subunit on the base substrate may be located within the orthographic projection range of the first covering subunit on the base substrate, and the orthographic projection of the third light-emitting subunit on the base substrate may be located within the orthographic projection range of the second covering subunit on the base substrate.

[0138] Alternatively, the orthographic projection of each light emitting unit on the base substrate may be located within the orthographic projection range of a covering sub-unit on the base substrate.

[0139] Optionally, along a direction perpendicular to the substrate, a ratio of a thickness of the covering unit to a thickness of the auxiliary electrode layer is K7, 0.25≤K7≤8;

[0140] Further, the thickness of the above-mentioned covering unit may be D1, 10nm≤D1≤40nm; the thickness of the auxiliary electrode layer is D2, 5nm≤D2≤40nm. For example, when the thickness of the covering unit is greater than the thickness of the auxiliary electrode layer, D1 may be 20nm, and D2 may be 5nm; when the thickness of the covering unit is equal to the thickness of the auxiliary electrode layer, D1 and D2 may both be 10nm; when the thickness of the covering unit is less than the thickness of the auxiliary electrode layer, D1 may be 15nm, and D2 may be 35nm.

[0141] Optionally, the material of the covering unit may include CPM (Conductor PatternMaterial, material for patterning conductive material) material, CPM material can be a nucleation inhibition material for metal electrode material, and the nucleation inhibition material for metal electrode material can include polytetrafluoroethylene (PTFE), silicon or silicone-based polymer, 3-(4-biphenyl)-4-phenyl-5-tert-butylphenyl-1,2,4-triazole (TAZ), bis(2-methyl-8-hydroxyquinoline-p-hydroxy (quninolinato))-4-biphenol aluminum (III) (BAlq), 2-(4-(9,10-di(naphthalene-2-yl)anthracene-2-yl)phenyl)-1-phenyl-1H-benzo-[D]imidazole (LG201), 8-hydroxyquinoline lithium (Liq), N(biphenyl-4-yl)9,9-dimethyl-N-(4(9-phenyl-9H-carbazole-3-yl)phenyl)-9H-fluorene-2-amine (HT211), etc. One or more of the above, not limited here.

[0142] Optionally, as the thickness of the covering unit increases, under the same evaporation conditions, the residual thickness of the metal electrode material will gradually decrease, and the light transmittance of the light-emitting substrate will gradually increase; the inventors conducted experiments on this, as shown in the experimental data in Table 2, such as Fig.12 Shown is a sampling diagram for the covering layer in each sample; Sample 1 does not add the first covering layer, Sample 2 is provided with a first covering layer with a thickness of 10nm, and Sample 3 is provided with a first covering layer with a thickness of 15nm. It can be seen that as the thickness of the first covering layer increases, the transmittance of the light-emitting substrate also gradually increases.

[0143] Table 2

[0144]

[0145]

[0146] The embodiment of the present application sets spaced covering units between the cathode layer and the second covering layer with a high refractive index, and then forms an auxiliary electrode layer with a mesh structure having multiple opening areas by vapor deposition, wherein the auxiliary electrode layer is in contact with the cathode, thereby greatly reducing the square resistance of the cathode layer, improving the voltage drop distribution of the screen, and enhancing the brightness uniformity of the screen.

[0147] A possible implementation method is provided in an embodiment of the present application, wherein the light-emitting substrate further includes an undulating structure layer, and the undulating structure layer at least includes a second covering layer and a first inorganic encapsulation layer;

[0148] Along the direction perpendicular to the base substrate, the thickness of the covering unit is less than the thickness of the auxiliary electrode layer; the undulating structure layer includes a first protruding portion and a plurality of first recessed portions, the orthographic projection of the first recessed portion on the base substrate at least partially overlaps with the orthographic projection of the covering unit on the base substrate, and the orthographic projection of the first protruding portion on the base substrate at least partially overlaps with the orthographic projection of the auxiliary electrode layer on the base substrate.

[0149] Optionally, the first recessed portion includes a first flat portion and a first climbing portion surrounding the first flat portion, and the distances between the first flat portions of different first recessed portions and the anode layer are approximately equal. It can be understood that the above-mentioned approximately equal can be completely equal or approximately equal within the process error range. Along the direction away from the central axis of the first flat portion, the height of the first climbing portion is positively correlated with the first distance; wherein the first distance is the distance between the first climbing portion and the central axis of the first flat portion. The surface of the above-mentioned first climbing portion away from the substrate substrate can be a plane or a curved surface with a certain curvature, which is not specifically limited in the embodiments of the present application.

[0150] In some embodiments, when each covering unit corresponds to a light-emitting sub-unit, the orthographic projection of the first flat portion on the base substrate is located at the center of the orthographic projection of the light-emitting sub-unit on the base substrate; when each covering unit corresponds to a light-emitting unit, the orthographic projection of the first flat portion on the base substrate is located at the center of the orthographic projection of the light-emitting unit on the base substrate.

[0151] like Fig.13 As shown, since the thickness of the low-refractive-index covering unit is less than that of the auxiliary electrode layer, the auxiliary electrode layer forms a bulge between the low-refractive-index covering units, and the undulating structure layer may include a second covering layer, a third covering layer, and a first inorganic encapsulation layer. The concave portion of the undulating structure layer corresponds to the covering unit and the light-emitting subunit.

[0152] In the embodiment of the present application, the raised auxiliary electrode layer can scatter light that cannot be emitted at a large angle, and the undulating structure layer can also effectively improve the light extraction of the device, reduce the light loss caused by the waveguide mode, and effectively improve the luminous efficiency. At the same time, this undulating structure increases the light output while increasing the isotropy of the device light output, which can greatly improve the visual color deviation caused by the microcavity effect.

[0153] A possible implementation method is provided in an embodiment of the present application, wherein the light-emitting substrate further includes an undulating structure layer, and the undulating structure layer at least includes a second covering layer and a first inorganic encapsulation layer;

[0154] Along the direction perpendicular to the base substrate, the thickness of the covering unit is greater than the thickness of the auxiliary electrode layer; the undulating structure layer includes a second recessed portion and a plurality of second protruding portions, and the orthographic projection of the second protruding portion on the base substrate at least partially overlaps with the orthographic projection of the covering unit on the base substrate; the orthographic projection of the second recessed portion on the base substrate at least partially overlaps with the orthographic projection of the auxiliary electrode layer on the base substrate.

[0155] Optionally, each second protrusion includes a second flat portion and a second climbing portion surrounding the second flat portion, and the distances between the second flat portions of different second protrusions and the anode layer are approximately equal. It can be understood that the above-mentioned approximately equal can be completely equal or approximately equal within the process error range; along the direction away from the central axis of the second flat portion, the height of the second climbing portion is negatively correlated with the second distance; wherein the second distance is the distance between the second climbing portion and the central axis of the second flat portion. The surface of the above-mentioned second climbing portion away from the substrate can be a plane or a curved surface with a certain curvature, which is not specifically limited in the embodiments of the present application.

[0156] In some embodiments, when each covering unit corresponds to a light-emitting sub-unit, the orthographic projection of the second flat portion on the base substrate is located at the center of the orthographic projection of the light-emitting sub-unit on the base substrate; when each covering unit corresponds to a light-emitting unit, the orthographic projection of the second flat portion on the base substrate is located at the center of the orthographic projection of the light-emitting unit on the base substrate.

[0157] like Fig.14 As shown, since the thickness of the low-refractive-index covering unit is greater than that of the auxiliary electrode layer, a depression is formed in the auxiliary electrode layer between the low-refractive-index covering units, and the undulating structure layer may include a second covering layer, a third covering layer, and a first inorganic encapsulation layer. The depression of the undulating structure layer corresponds to the covering unit and the light-emitting subunit.

[0158] In the embodiment of the present application, the concave auxiliary electrode layer can scatter light that cannot be emitted at a large angle, and the undulating structure layer can also effectively improve the light extraction of the device, reduce the light loss caused by the waveguide mode, and effectively improve the luminous efficiency. At the same time, this undulating structure increases the light output while increasing the isotropy of the device light output, which can greatly improve the visual color deviation caused by the microcavity effect.

[0159] The light-emitting substrate provided in the present application can sequentially arrange an anode layer, an electroluminescent layer and a cathode layer on one side of a substrate, and then arrange a first covering layer on the side of the cathode layer away from the substrate, and sequentially arrange a second covering layer and a packaging structure layer on the side of the first covering layer away from the substrate; wherein the packaging structure layer may include at least one inorganic layer, the refractive index of the second covering layer is greater than the refractive index of the first covering layer, and the refractive index of the second covering layer is also greater than the refractive index of the inorganic layer closest to the second covering layer in at least one inorganic layer, which can effectively enhance the light transmittance of the multi-film layer. At the same time, the arrangement of the first covering layer in the present application can effectively increase the spacing distance between the light-emitting microcavity and the packaging structure layer, improve the coupling efficiency between the light-emitting microcavity and the packaging structure layer, eliminate the resonance mismatch between the light-emitting microcavity and the strong reflective film layer structure, and effectively improve the light-emitting efficiency of the light-emitting substrate.

[0160] A display device is provided in an embodiment of the present application, including the display substrate provided in the embodiment of the present application. The display device may include a display panel, a display screen, a mobile phone, a tablet computer, a television, etc.

[0161] An embodiment of the present application provides a lighting device, which may include the light-emitting substrate provided in the embodiment of the present application.

[0162] Optionally, the lighting device may include a car lamp, a street lamp, a traffic light, etc. It should be noted that in the embodiment of the present application, the structure of the light-emitting substrate is the same as that of the light-emitting substrate in the above embodiments, and will not be described in detail here.

[0163] In the above description, the technical details such as the patterning of each layer are not described in detail. However, those skilled in the art should understand that various technical means can be used to form layers, regions, etc. of desired shapes. In addition, in order to form the same structure, those skilled in the art can also design methods that are not completely the same as the methods described above. In addition, although the various embodiments are described above separately, this does not mean that the measures in the various embodiments cannot be used in combination to advantage.

[0164] Although the preferred embodiments of the present application have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present application.

[0165] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A light-emitting substrate, characterized in that: The light-emitting substrate comprises: substrate substrate; An anode layer is arranged on one side of the substrate; An electroluminescent layer is disposed on a side of the anode layer away from the substrate; A cathode layer, disposed on a side of the electroluminescent layer away from the substrate; A first covering layer is disposed on a side of the cathode layer away from the substrate; A second covering layer is arranged on a side of the first covering layer away from the base substrate; the refractive index of the second covering layer is greater than the refractive index of the first covering layer; The packaging structure layer includes a first inorganic packaging layer, which is arranged on a side of the second covering layer away from the substrate; wherein the first inorganic packaging layer includes at least one inorganic layer, and the refractive index of the inorganic layer closest to the second covering layer among the at least one inorganic layer is smaller than the refractive index of the second covering layer.

2. The light-emitting substrate according to claim 1, characterized in that: The light-emitting substrate further comprises: A third covering layer is disposed between the second covering layer and the packaging structure layer; wherein a refractive index of the third covering layer is smaller than a refractive index of the second covering layer, and a refractive index of the third covering layer is smaller than a refractive index of the inorganic layer closest to the second covering layer among the at least one inorganic layer.

3. The light-emitting substrate according to claim 1, characterized in that: The first covering layer includes a plurality of covering units distributed at intervals; the light-emitting substrate further includes an auxiliary electrode layer, which is arranged on a side of the cathode layer away from the base substrate and in contact with the cathode layer; the auxiliary electrode layer has a plurality of opening areas, and the covering units are located in the opening areas; The electroluminescent layer includes a plurality of light-emitting units, and an orthographic projection of the covering unit on the base substrate at least partially overlaps with an orthographic projection of at least one of the light-emitting units on the base substrate.

4. The light-emitting substrate according to claim 3, characterized in that: Each of the light-emitting units includes a plurality of light-emitting sub-units, and the covering unit includes a plurality of covering sub-units; the orthographic projection of each of the covering sub-units on the base substrate overlaps with the orthographic projection of a light-emitting sub-unit on the base substrate.

5. The light-emitting substrate according to claim 3, characterized in that: Each of the light-emitting units includes a first light-emitting subunit, a second light-emitting subunit and a third light-emitting subunit, and the covering unit includes a first covering subunit and a second covering subunit; the orthographic projection of the first covering subunit on the base substrate overlaps with the orthographic projections of the first light-emitting subunit and the second light-emitting subunit on the base substrate; The orthographic projection of the second covering subunit on the base substrate overlaps with the orthographic projection of the third light emitting subunit on the base substrate.

6. The light-emitting substrate according to claim 5, characterized in that: The first light-emitting subunit and the second light-emitting subunit are arranged along a first direction, the third light-emitting subunit is arranged on one side of the first light-emitting subunit and the second light-emitting subunit, and the area of ​​the first light-emitting subunit and the area of ​​the second light-emitting subunit are both smaller than the area of ​​the third light-emitting subunit; The orthographic projections of the first light-emitting sub-unit and the second light-emitting sub-unit on the base substrate are located within the orthographic projection range of the first covering sub-unit on the base substrate, and the first covering sub-unit also includes a middle portion between the first light-emitting sub-unit and the second light-emitting sub-unit, and the width of the middle portion in the first direction is greater than the target distance; wherein the target distance is the distance between the orthographic projection edge of the first covering sub-unit on the base substrate and the orthographic projection edge of the first light-emitting sub-unit on the base substrate in the first direction.

7. The light-emitting substrate according to claim 3, characterized in that: The orthographic projection of the light emitting unit on the base substrate is located within the orthographic projection range of the covering unit on the base substrate.

8. The light emitting substrate according to claim 3, characterized in that: The light-emitting substrate further comprises an undulating structure layer, wherein the undulating structure layer at least comprises the second covering layer and the first inorganic encapsulation layer; Along the direction perpendicular to the base substrate, the thickness of the covering unit is less than the thickness of the auxiliary electrode layer; the undulating structure layer includes a first protruding portion and a plurality of first recessed portions, the orthographic projection of the first recessed portion on the base substrate at least partially overlaps with the orthographic projection of the covering unit on the base substrate, and the orthographic projection of the first protruding portion on the base substrate at least partially overlaps with the orthographic projection of the auxiliary electrode layer on the base substrate.

9. The light-emitting substrate according to claim 8, characterized in that: The first recessed portion includes a first flat portion and a first climbing portion surrounding the first flat portion, and the distances between the first flat portions of the first recessed portions and the anode layer are substantially equal; along a direction away from the central axis of the first flat portion, a height of the first climbing portion is positively correlated with the first distance; wherein the first distance is the distance between the first climbing portion and the central axis of the first flat portion.

10. The light emitting diode according to claim 3, characterized in that: The light-emitting substrate further comprises an undulating structure layer, wherein the undulating structure layer at least comprises the second covering layer and the first inorganic encapsulation layer; Along a direction perpendicular to the base substrate, the thickness of the covering unit is greater than the thickness of the auxiliary electrode layer; the undulating structure layer comprises a second recessed portion and a plurality of second protruding portions, and the orthographic projection of the second protruding portions on the base substrate at least partially overlaps with the orthographic projection of the covering unit on the base substrate; An orthographic projection of the second recessed portion on the base substrate at least partially overlaps with an orthographic projection of the auxiliary electrode layer on the base substrate.

11. The light emitting substrate according to claim 10, characterized in that: The second protrusion includes a second flat portion and a second climbing portion surrounding the second flat portion, and the distances between the second flat portions of the second protrusions and the anode layer are substantially equal; along the direction away from the central axis of the second flat portion, the height of the second climbing portion is negatively correlated with the second distance; wherein the second distance is the distance between the second climbing portion and the central axis of the second flat portion.

12. The light emitting substrate according to claim 1, characterized in that: The at least one inorganic layer comprises a first encapsulation sublayer, a second encapsulation sublayer and a third encapsulation sublayer; Wherein, the first encapsulation sublayer is arranged on a side of the second covering layer away from the substrate; The second encapsulation sublayer is arranged on a side of the first encapsulation sublayer away from the substrate; The third encapsulation sublayer is arranged on a side of the second encapsulation sublayer away from the substrate; The refractive index of the second encapsulation sublayer is greater than the refractive index of the first encapsulation sublayer, and the refractive index of the second encapsulation sublayer is greater than the refractive index of the third encapsulation sublayer.

13. The light emitting substrate according to claim 12, characterized in that: The at least one inorganic layer further includes a fourth encapsulation sublayer, which is disposed between the first encapsulation sublayer and the second encapsulation sublayer; and a refractive index of the fourth encapsulation sublayer is greater than a refractive index of the second encapsulation sublayer.

14. The light emitting substrate according to claim 1, characterized in that: The ratio of the refractive index of the second covering layer to the refractive index of the first covering layer is K1, and 1.18<K1<1.

93.

15. The light emitting substrate according to claim 14, characterized in that: The refractive index of the first covering layer is N1, 1.35≤N1≤1.7; the refractive index of the second covering layer is N2, 2.0≤N2≤2.

6.

16. The light emitting substrate according to claim 2, characterized in that: The ratio of the refractive index of the second covering layer to the refractive index of the third covering layer is K2, 1.25≤K2≤2; the ratio of the refractive index of the first encapsulation sublayer to the refractive index of the third covering layer is K3, 1<K3<1.

24.

17. The light emitting substrate according to claim 12, characterized in that: The ratio of the refractive index of the second encapsulation sublayer to the refractive index of the first encapsulation sublayer is K4, 1<K4<1.47; the ratio of the refractive index of the second encapsulation sublayer to the refractive index of the third encapsulation sublayer is K5, 1<K5<1.

27.

18. The light emitting substrate according to claim 13, characterized in that: The ratio of the refractive index of the fourth encapsulation sublayer to the refractive index of the second encapsulation sublayer is K6, 1<K6≤1.

25.

19. A lighting device, characterized in that: The lighting device comprises the light-emitting substrate according to any one of claims 1 to 18.

20. A display device, characterized in that: The display device comprises the light-emitting substrate according to any one of claims 1 to 18.

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