Light-emitting substrate and light-emitting device

Abstract

The embodiment of the utility model provides a light-emitting substrate and a light-emitting device, relates to the technical field of display, and is used for improving the electrical performance and the optical performance of the light-emitting device at the same time. The light-emitting substrate comprises a substrate and a plurality of light-emitting devices, the light-emitting devices are located on one side of the substrate, each light-emitting device comprises a first electrode, a light-emitting layer and a second electrode which are stacked, and the first electrode is closer to the substrate than the second electrode; the first electrode comprises a reflecting electrode, and the second electrode comprises a transparent electrode; wherein at least one light-emitting device comprises an optical adjustment structure, the optical adjustment structure comprises an optical adjustment layer and a transparent reflection layer, the optical adjustment layer is located on the side, away from the substrate, of the second electrode, and the transparent reflection layer is located on the side, away from the substrate, of the optical adjustment layer; the conductivity of the optical regulation and control layer is smaller than that of the transparent reflection layer, and the thickness of the optical regulation and control layer is different from that of the transparent reflection layer. The light-emitting substrate is used for displaying images.

Description

Technical Field

[0001] The present disclosure relates to the field of display technologies, and particularly to a light-emitting substrate and a light-emitting device. Background Art

[0002] As a new type of light-emitting material, quantum dots (QDs) have the advantages of high color purity, high light-emitting quantum efficiency, adjustable emission color, and long service life, and have become a research hotspot for new light-emitting materials of light-emitting diodes (LEDs). Therefore, quantum dot light-emitting diodes (QLEDs) using quantum dot materials as the light-emitting layer have become the main direction of research on new display devices. Summary of the Utility Model

[0003] An object of an embodiment of the present disclosure is to provide a light-emitting substrate and a light-emitting device for simultaneously improving the electrical performance and optical performance of the light-emitting device.

[0004] To achieve the above object, the embodiment of the present disclosure provides the following technical solutions:

[0005] On the one hand, a light-emitting substrate is provided. The light-emitting substrate includes: a substrate and a plurality of light-emitting devices. The plurality of light-emitting devices are located on one side of the substrate. Each light-emitting device includes a stacked first electrode, a light-emitting layer, and a second electrode. The first electrode is closer to the substrate than the second electrode; the first electrode includes a reflective electrode, and the second electrode includes a transparent electrode; wherein, at least one of the light-emitting devices includes: an optical adjustment structure, the optical adjustment structure includes an optical control layer and a transparent reflective layer. The optical control layer is located on the side of the second electrode away from the substrate, and the transparent reflective layer is located on the side of the optical control layer away from the substrate; the conductivity of the optical control layer is less than the conductivity of the transparent reflective layer, and the thicknesses of the optical control layer and the transparent reflective layer are different.

[0006] In the above light-emitting substrate, through the setting of the transparent reflective layer, a strong microcavity effect is formed between the first electrode and the transparent reflective layer. The light-emitting layer is located between the transparent reflective layer and the first electrode, that is, the light-emitting layer is located in the microcavity. Due to the microcavity effect, the intensity of light with a certain wavelength emitted by the light-emitting layer will be increased to improve the light-emitting efficiency of the light-emitting device.

[0007] Moreover, the cavity length of the microcavity can be adjusted by adjusting the thickness of the optical control layer. Since the optical control layer is located between the transparent reflective layer and the second electrode, the setting of the optical control layer will not affect the electrical performance of the light-emitting device. After adjusting the thicknesses of the layers between the first electrode and the second electrode to optimize the electrical performance of the light-emitting device, the thickness of the optical control layer can be adjusted to optimize the optical performance of the light-emitting device. Therefore, the embodiments of the present disclosure achieve the purpose of separately adjusting the optical and electrical performances of the light-emitting device by providing an optical adjustment structure on the side of the second electrode away from the substrate, so that the light-emitting device has excellent electrical and optical performances.

[0008] In some embodiments, the light transmittance of the optical control layer is greater than or equal to the light transmittance of the transparent reflective layer, and the range of the light transmittance of the optical control layer is greater than or equal to 90%.

[0009] In some embodiments, the extinction coefficient of the optical control layer ranges from 0.001 m -1 ~0.005 m -1 。

[0010] In some embodiments, the material of the optical control layer is selected from at least one of 4,4,4-tris(carbazol-9-yl)triphenylamine, N,N'-diphenyl-N,N'-(1-naphthyl)-1,1'-biphenyl-4,4'-diamine, 4,4'-bis(9-carbazolyl)biphenyl, silicon oxide, silicon nitride, and silicon oxynitride.

[0011] In some embodiments, the plurality of light-emitting devices include: a first light-emitting device configured to emit first-color light; the optical control layer includes: a first control portion correspondingly disposed with the first light-emitting device; wherein, the thickness range of the first control portion is 55 nm to 65 nm.

[0012] In some embodiments, the light-emitting substrate further includes: a light extraction layer located on the side of the transparent reflective layer away from the substrate; the light extraction layer includes: a first light extraction portion correspondingly disposed with the first light-emitting device; wherein, the thickness range of the first light extraction portion is 85 nm to 115 nm.

[0013] In some embodiments, the first light-emitting device further includes: a first hole transport layer; the first hole transport layer is located between the first electrode and the light-emitting layer of the first light-emitting device, or the first hole transport layer is located between the light-emitting layer and the second electrode of the first light-emitting device; wherein, the thickness range of the first hole transport layer is 20 nm to 30 nm.

[0014] In some embodiments, the first light-emitting device further includes: a first electron transport layer; the first electron transport layer is located between the first electrode of the first light-emitting device and the light-emitting layer of the first light-emitting device, or the first electron transport layer is located between the light-emitting layer of the first light-emitting device and the second electrode of the first light-emitting device; wherein, the thickness range of the first electron transport layer is 30 nm to 70 nm.

[0015] In some embodiments, the first light-emitting device further includes: a first hole transport layer and a first electron transport layer; the first electrode of the first light-emitting device, the first hole transport layer, the light-emitting layer of the first light-emitting device, the first electron transport layer, and the second electrode of the first light-emitting device are arranged in a direction away from the substrate; or, the first electrode of the first light-emitting device, the first electron transport layer, the light-emitting layer of the first light-emitting device, the first hole transport layer, and the second electrode of the first light-emitting device are arranged in a direction away from the substrate; wherein, the thickness range of the first hole transport layer is 20 nm to 30 nm; the thickness range of the first electron transport layer is 30 nm to 70 nm.

[0016] In some embodiments, the plurality of light-emitting devices includes: a second light-emitting device configured to emit second-color light; the optical modulation layer includes: a second modulation portion, and the second modulation portion is correspondingly arranged with the second light-emitting device; wherein, the thickness range of the second modulation portion is 95 nm to 115 nm.

[0017] In some embodiments, the light-emitting substrate further includes: a light extraction layer; the light extraction layer includes: a second light extraction portion, and the second light extraction portion is correspondingly arranged with the second light-emitting device; wherein, the thickness range of the second light extraction portion is 105 nm to 145 nm.

[0018] In some embodiments, the second light-emitting device further includes: a second hole transport layer; the second hole transport layer is located between the first electrode of the second light-emitting device and the light-emitting layer of the second light-emitting device, or the second hole transport layer is located between the light-emitting layer of the second light-emitting device and the second electrode of the second light-emitting device; wherein, the thickness range of the second hole transport layer is 20 nm to 30 nm.

[0019] In some embodiments, the second light-emitting device further includes: a second electron transport layer; the second electron transport layer is located between the first electrode of the second light-emitting device and the light-emitting layer of the second light-emitting device; or, the second electron transport layer is located between the light-emitting layer of the second light-emitting device and the second electrode of the second light-emitting device; wherein, the thickness range of the second electron transport layer is 30 nm to 70 nm.

[0020] In some embodiments, the second light-emitting device further includes: a second hole transport layer and a second electron transport layer; the first electrode, the second hole transport layer, the light-emitting layer of the second light-emitting device, the second electron transport layer, and the second electrode of the second light-emitting device are arranged in a direction away from the substrate; or, the first electrode, the second electron transport layer, the light-emitting layer of the second light-emitting device, the second hole transport layer, and the second electrode of the second light-emitting device are arranged in a direction away from the substrate; wherein, the thickness range of the second hole transport layer is 20 nm to 30 nm; the thickness range of the second electron transport layer is 30 nm to 70 nm.

[0021] In some embodiments, the plurality of light-emitting devices includes: a third light-emitting device configured to emit third-color light; the optical modulation layer includes: a third modulation portion correspondingly arranged with the third light-emitting device; wherein, the thickness range of the third modulation portion is 5 nm to 15 nm.

[0022] In some embodiments, the light-emitting substrate further includes: a light extraction layer; the light extraction layer includes: a third light extraction portion correspondingly arranged with the third light-emitting device; wherein, the thickness range of the third light extraction portion is 55 nm to 85 nm.

[0023] In some embodiments, the third light-emitting device further includes: a third hole transport layer; the third hole transport layer is located between the first electrode and the light-emitting layer of the third light-emitting device; or, the third hole transport layer is located between the light-emitting layer and the second electrode of the third light-emitting device; wherein, the thickness range of the third hole transport layer is 20 nm to 40 nm.

[0024] In some embodiments, the third light-emitting device further includes: a third electron transport layer; the third electron transport layer is located between the first electrode and the light-emitting layer of the third light-emitting device; or, the third electron transport layer is located between the light-emitting layer and the second electrode of the third light-emitting device; wherein, the thickness range of the third electron transport layer is 40 nm to 80 nm.

[0025] In some embodiments, the third light-emitting device further includes: a third hole transport layer and a third electron transport layer; the first electrode, the third hole transport layer, the light-emitting layer of the third light-emitting device, the third electron transport layer, and the second electrode of the third light-emitting device are arranged in a direction away from the substrate; or, the first electrode, the third electron transport layer, the light-emitting layer of the third light-emitting device, the third hole transport layer, and the second electrode of the third light-emitting device are arranged in a direction away from the substrate; wherein, the thickness range of the third hole transport layer is 20nm to 40nm; the thickness range of the third electron transport layer is 40nm to 80nm.

[0026] In some embodiments, the light transmittance of the transparent reflective layer ranges from greater than or equal to 60% to less than or equal to 90%; and / or, in the wavelength range of 400nm to 700nm, the light transmittance of the second electrode ranges from greater than or equal to 85%.

[0027] In some embodiments, the materials of the transparent reflective layer and the second electrode are independently selected from at least one of gold, silver, magnesium-silver alloy, molybdenum oxide, indium tin oxide, indium zinc oxide, indium tin zinc oxide, indium gallium oxide, and aluminum-doped zinc oxide.

[0028] On the other hand, a light-emitting device is provided. The light-emitting device includes: a light-emitting substrate as described in any one of the above embodiments. The light-emitting device further includes: a driving chip for driving the light-emitting substrate to emit light.

[0029] The above light-emitting device has the same structure and beneficial technical effects as the light-emitting substrate provided in some of the above embodiments, and will not be elaborated here. Description of the Drawings

[0030] In order to more clearly illustrate the technical solutions in the present disclosure, the drawings required for some embodiments of the present disclosure will be briefly introduced below. Obviously, the drawings in the following description are only the drawings of some embodiments of the present disclosure, and those of ordinary skill in the art can also obtain other drawings based on these drawings. In addition, the drawings in the following description can be regarded as schematic diagrams, and are not limitations on the actual sizes of the products, the actual processes of the methods, etc. involved in the embodiments of the present disclosure.

[0031] Figure 1 It is a structural diagram of a light-emitting device according to some embodiments of the present disclosure;

[0032] Figure 2 It is a structural diagram of a light-emitting substrate according to some embodiments of the present disclosure;

[0033] Figure 3Optical path diagram of a light-emitting substrate according to some embodiments of the present disclosure;

[0034] Figure 4 Luminous intensity diagram of a light-emitting device according to some embodiments of the present disclosure;

[0035] Figure 5 Graph of the relationship between the forward current efficiency and voltage of a light-emitting device according to some embodiments of the present disclosure;

[0036] Figure 6 Graph of the relationship between the external quantum efficiency and voltage of a light-emitting device according to some embodiments of the present disclosure;

[0037] Figure 7 Luminous angle distribution diagram of the light-emitting device according to Example 1 of the present disclosure;

[0038] Figure 8 Luminous angle distribution diagram of the light-emitting device according to Example 2 of the present disclosure;

[0039] Figure 9 Graph of the relationship between the luminous intensity and voltage of a light-emitting device according to some embodiments of the present disclosure;

[0040] Figure 10 Luminous angle distribution diagram of the light-emitting device according to Example 3 of the present disclosure;

[0041] Figure 11 Graph of the relationship between the luminous intensity and voltage of the light-emitting device according to Example 3 of the present disclosure;

[0042] Figure 12 Graph of the relationship between the external quantum efficiency and voltage of the light-emitting device according to Example 3 of the present disclosure;

[0043] Figure 13 Another structural diagram of a light-emitting substrate according to some embodiments of the present disclosure;

[0044] Figure 14 Another optical path diagram of a light-emitting substrate according to some embodiments of the present disclosure;

[0045] Figure 15 Luminous intensity diagram of the first light-emitting device according to some embodiments of the present disclosure;

[0046] Figure 16 Another structural diagram of a light-emitting substrate according to some embodiments of the present disclosure;

[0047] Figure 17 Another structural diagram of a light-emitting substrate according to some embodiments of the present disclosure;

[0048] Figure 18 Another structural diagram of a light-emitting substrate according to some embodiments of the present disclosure;

[0049] Figure 19 Another structural diagram of a light-emitting substrate according to some embodiments of the present disclosure;

[0050] Figure 20 Another structural diagram of a light-emitting substrate according to some embodiments of the present disclosure;

[0051] Figure 21 Light output luminance diagram of a second light-emitting device according to some embodiments of the present disclosure;

[0052] Figure 22 Light output luminance diagram of a third light-emitting device according to some embodiments of the present disclosure. Detailed implementation manners

[0053] Next, the technical solutions in some embodiments of the present disclosure will be clearly and completely described in conjunction with the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present disclosure, rather than all of the embodiments. Based on the embodiments provided by the present disclosure, all other embodiments obtained by those of ordinary skill in the art belong to the scope of protection of the present disclosure.

[0054] Unless otherwise required by the context, throughout the specification and claims, the term "comprise" and its other forms, such as the third-person singular form "comprises" and the present participle form "comprising", are interpreted as open and inclusive, that is, "including, but not limited to". In the description of the specification, the terms "one embodiment", "some embodiments", "exemplary embodiments", "example", "specific example" or "some examples", etc., are intended to indicate that the specific features, structures, materials or characteristics related to the embodiment or example are included in at least one embodiment or example of the present disclosure. The schematic representations of the above terms are not necessarily referring to the same embodiment or example. In addition, the specific features, structures, materials or characteristics may be included in any one or more embodiments or examples in any appropriate manner.

[0055] Hereinafter, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the embodiments of the present disclosure, unless otherwise stated, the meaning of "a plurality" is two or more.

[0056] In describing some embodiments, the terms "coupled" and "connected" and their derivatives may be used. The term "connected" should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or integrated; it can be directly connected or indirectly connected through an intermediate medium. The term "coupled" indicates, for example, that two or more components have direct physical contact or electrical contact. The term "coupled" or "communicatively coupled" may also refer to two or more components that do not have direct contact with each other but still cooperate or interact with each other. The embodiments disclosed herein are not necessarily limited to the content herein.

[0057] "At least one of A, B, and C" has the same meaning as "at least one of A, B, or C", and both include the following combinations of A, B, and C: only A, only B, only C, the combination of A and B, the combination of A and C, the combination of B and C, and the combination of A, B, and C.

[0058] "A and / or B" includes the following three combinations: only A, only B, and the combination of A and B.

[0059] As used herein, "about", "substantially", or "approximately" includes the stated value and the average value within an acceptable deviation range of the specific value, where the acceptable deviation range is determined by a person of ordinary skill in the art considering the measurement being discussed and the errors associated with the measurement of a particular quantity (i.e., the limitations of the measurement system).

[0060] As used herein, "parallel", "perpendicular", "equal" include the stated situations and situations similar to the stated situations, and the range of the similar situations is within an acceptable deviation range, where the acceptable deviation range is determined by a person of ordinary skill in the art considering the measurement being discussed and the errors associated with the measurement of a particular quantity (i.e., the limitations of the measurement system). For example, "parallel" includes absolute parallel and approximate parallel, where the acceptable deviation range of approximate parallel can be, for example, within 5° deviation; "perpendicular" includes absolute perpendicular and approximate perpendicular, where the acceptable deviation range of approximate perpendicular can also be, for example, within 5° deviation. "Equal" includes absolute equal and approximate equal, where the acceptable deviation range of approximate equal can be, for example, the difference between the two equal values is less than or equal to 5% of either one of them.

[0061] It should be understood that when a layer or element is referred to as being on another layer or substrate, it can be that the layer or element is directly on the other layer or substrate, or there can be an intermediate layer between the layer or element and the other layer or substrate.

[0062] Exemplary embodiments are described herein with reference to cross-sectional and / or plan views that are idealized exemplary drawings. In the drawings, the thickness of layers and the area of regions are enlarged for clarity. Thus, variations in the shape relative to the drawings due to, for example, manufacturing techniques and / or tolerances are contemplated. Accordingly, the exemplary embodiments should not be construed as limited to the shapes of the regions shown herein, but include shape deviations resulting from, for example, manufacturing. For example, an etched region shown as rectangular will typically have curved features. Thus, the regions shown in the drawings are schematic in nature, and their shapes are not intended to depict the actual shape of the regions of the device and are not intended to limit the scope of the exemplary embodiments.

[0063] As Figure 1 shown, some embodiments of the present disclosure provide a light-emitting device 1000, which can be any device that displays whether it is moving (e.g., video) or stationary (e.g., still image), and whether it is text or image. More specifically, it is contemplated that the embodiments can be implemented in or associated with a variety of electronic devices, such as (but not limited to) mobile phones (e.g., cell phones), wireless devices, personal data assistants (PDAs), handheld or portable computers, GPS receivers / navigators, cameras, MP4 video players, video cameras, game consoles, watches, clocks, calculators, television monitors, flat panel displays, computer monitors, automotive displays (e.g., odometer displays, etc.), navigators, cockpit controllers and / or displays, displays for camera views (e.g., displays for rearview cameras in vehicles), electronic photos, electronic billboards or signs, projectors, architectural structures, packaging, and aesthetic structures (e.g., displays for images of a piece of jewelry), etc. Figure 1 For example, the light-emitting device 1000 is taken as a mobile phone for illustration.

[0064] Exemplarily, the light-emitting device 1000 can be an electroluminescent display device or a photoluminescent display device. In the case where the light-emitting device 1000 is an electroluminescent display device, the electroluminescent display device can be an organic light-emitting diode (OLED) display device or a quantum dot light-emitting diode (QLED) display device. Hereinafter, some embodiments of the present disclosure will be schematically described by taking the light-emitting device 1000 as a QLED display device as an example. However, the embodiments of the present disclosure include but are not limited to this, and any other display device can also be considered as long as the same technical concept is applied.

[0065] Please continue to refer to Figure 1 , the above-mentioned light-emitting device 1000 includes a light-emitting substrate 100.

[0066] In some embodiments, as Figure 2 shown, the light-emitting substrate 100 includes: a substrate 11 and a plurality of light-emitting devices 10 located on one side of the substrate 11. Each light-emitting device 10 among the plurality of light-emitting devices 10 includes a stacked first electrode 12, a light-emitting layer 15, and a second electrode 17. The first electrode 12 is closer to the substrate 11 than the second electrode 17.

[0067] Exemplarily, as Figure 2 shown, the light-emitting substrate 100 further includes a pixel defining layer 20. A plurality of openings K are provided on the pixel defining layer 20, and the plurality of light-emitting devices 10 are disposed in the plurality of openings K in a one-to-one correspondence.

[0068] Exemplarily, the plurality of light-emitting devices 10 include: a first light-emitting device 101, a second light-emitting device 102, and a third light-emitting device 103. For example, the first light-emitting device 101 is configured to emit any one of red light, green light, and blue light, the second light-emitting device 102 is configured to emit another one of red light, green light, and blue light, and the third light-emitting device 103 is configured to emit the last one of red light, green light, and blue light.

[0069] Exemplarily, the first electrode 12 is one of an anode and a cathode, and the second electrode 17 is the other one of the anode and the cathode.

[0070] In some embodiments, as Figure 2 shown, the light-emitting substrate 100 further includes: a pixel driving circuit (not shown in the figure) located between the substrate 11 and the plurality of light-emitting devices 10. The pixel driving circuit is configured to provide an electrical signal to the plurality of light-emitting devices 10 to drive the light-emitting devices 10 to emit light.

[0071] The light-emitting principle of the light-emitting device 10 is as follows: through a circuit connected by the anode and the cathode, holes are injected into the light-emitting layer 15 by the anode, electrons are injected into the light-emitting layer 15 by the cathode, and the formed electrons and holes form excitons in the light-emitting layer 15. The excitons return to the ground state through radiative transition and emit photons.

[0072] In some embodiments, as Figure 3 shown, taking the first electrode 12 as the anode and the second electrode 17 as the cathode as an example, the light-emitting device 10 further includes: a hole injection layer 13 and a hole transport layer 14 located between the first electrode 12 and the light-emitting layer 15. The hole injection layer 13 and the hole transport layer 14 are disposed in a direction away from the substrate 11. The light-emitting device 10 further includes: an electron transport layer 16 located between the light-emitting layer 15 and the second electrode 17.

[0073] The provision of the hole injection layer 13 and the hole transport layer 14 can improve the hole transport efficiency of the light-emitting device 10, and the provision of the electron transport layer 16 can improve the electron transport efficiency of the light-emitting device 10, so as to increase the rate of forming excitons by electrons and holes in the light-emitting layer 15, thereby improving the light-emitting efficiency of the light-emitting device 10.

[0074] Exemplarily, a light extraction layer 18 is provided on the side of the second electrode 17 away from the substrate 11. For example, the refractive index of the light extraction layer 18 is less than that of the second electrode 17 and greater than that of air. Thus, due to the influence of the refractive index, the provision of the light extraction layer 18 can reduce the total reflection of light at the film interface, so as to improve the light extraction efficiency of the light-emitting device 10.

[0075] The light-emitting device 10 can be divided into a top-emission type light-emitting device and a bottom-emission type light-emitting device. For example, the first electrode 12 can be set as a transparent electrode and the second electrode 17 can be set as a reflective electrode; alternatively, the first electrode 12 can be set as a reflective electrode and the second electrode 17 can be set as a transparent electrode. The difference between the two lies in whether the light-emitting direction of the light-emitting device 10 is through the substrate 11 or away from the substrate 11.

[0076] Since the top-emission type light-emitting device emits light from the top and there is no need to avoid the metal traces of the thin film transistor (TFT) array for forming the pixel driving circuit at the bottom, therefore, the pixel design of the top-emission type light-emitting device is more flexible and has a higher aperture ratio than the bottom-emission type light-emitting device. Therefore, the embodiments of the present disclosure will be described by taking the light-emitting device 10 as an example of a top-emission type light-emitting device.

[0077] However, in the top-emission type light-emitting device, it is a difficult problem to make the thicknesses of the functional layers of the light-emitting device 10 simultaneously satisfy the better electrical performance and the better optical performance of the light-emitting device 10. For example, when the thicknesses of the functional layers of the light-emitting device 10 satisfy the better electrical performance of the light-emitting device 10, at this time, the carrier (electron and hole) transport of the light-emitting device 10 is relatively balanced. However, the side light emission of the light-emitting device 10 is strong, resulting in poor optical performance of the light-emitting device 10. And when the thicknesses of the functional layers of the light-emitting device 10 satisfy the better optical performance of the light-emitting device 10, at this time, the front light emission of the light-emitting device 10 is strong. However, the carrier injection of the light-emitting device 10 is unbalanced, resulting in poor electrical performance of the light-emitting device 10.

[0078] It should be noted that when the electrical performance of the light-emitting device 10 is relatively good, the external quantum efficiency of the light-emitting device 10 is relatively high. Among them, the external quantum efficiency (External Quantum Efficiency, EQE) refers to the efficiency that the light generated in the light-emitting layer 15 is extracted to the outside of the light-emitting device 10. When the optical performance of the light-emitting device 10 is relatively good, the forward current efficiency of the light-emitting device 10 is relatively high. Among them, the forward current efficiency refers to the ratio of the light extraction efficiency to the current on the front side of the light-emitting device 10.

[0079] Among them, as Figure 3 shown, forward light emission means that the angle between the light ray and the first direction Y is approximately 0°, and the first direction Y is the direction perpendicular to the substrate 11; side light emission means the light rays other than forward light emission.

[0080] Regarding the relationship between the thicknesses of the respective functional layers of the light-emitting device 10 and the electrical and optical performances of the light-emitting device 10, the following embodiments are provided.

[0081] In some embodiments, as Figure 3 shown, the first electrode 12 is a reflective electrode, and the second electrode 17 is a semi-transparent and semi-reflective electrode.

[0082] It should be noted that the reflective electrode is used to reflect the light rays incident on the electrode. The material of the first electrode 12 is, for example, a metal, and the first electrode 12 can be a single-layer structure or a stacked structure. For example, the reflectivity of the reflective electrode is greater than 90%. The semi-transparent and semi-reflective electrode is used to reflect a part of the light rays incident on the electrode and also to transmit a part of the light rays incident on the electrode.

[0083] In this light-emitting device 10, the first electrode 12 and the second electrode 17 form a microcavity (also referred to as a resonant cavity). The light-emitting layer 15 is located between the first electrode 12 and the second electrode 17, that is, the light-emitting layer 15 is located inside the microcavity. The intensity of the light with a certain wavelength emitted by the light-emitting layer 15 will be increased, and the spectrum of the light with a certain wavelength will be narrowed. The microcavity can cause most of the light rays emitted by the light-emitting layer 15 to be emitted through the second electrode 17, improving the light-emitting efficiency of the light-emitting device 10.

[0084] That is to say, there is a microcavity effect in the light-emitting device 10. Specifically, the microcavity effect mainly refers to the optical interference inside the light-emitting device 10. The light will be reflected back and forth inside the light-emitting device 10, and only the light with a specific wavelength can be emitted to the outside of the light-emitting device 10. Moreover, when the light-emitting layer 15 of the light-emitting device 10 is located inside a microcavity formed by a reflective electrode and a semi-transparent and semi-reflective electrode, when the length of the microcavity is on the same order of magnitude as the wavelength of the light wave, the light with a specific wavelength will be selected and enhanced, and the spectrum will be narrowed.

[0085] Among them, the microcavity length refers to the dimension d1 of the microcavity structure in the first direction Y, which can also be understood as the distance between the first electrode 12 and the second electrode 17. The first direction Y is perpendicular to the substrate 11.

[0086] In this top-emitting light-emitting device, Fabry-Perot interference occurs between the first electrode 12 and the second electrode 17. Fabry-Perot interference mainly has two mechanisms. First, the interference between the emitted light L1 directly emitted from the light-emitting layer 15 and the reflected light L2 of the first electrode 12 is wide-angle interference. Second, the mutual interference between multiple reflected lights L2 is multi-beam interference.

[0087] Moreover, electromagnetic waves will be absorbed at the dielectric-metal interface L3. When light is reflected at the first electrode 12 formed of a metal material, a phase shift will occur. Therefore, the microcavity length of the top-emitting light-emitting device needs to be determined considering the differences in the optical path and phase shift between the beams at the dielectric-metal interface L3. Among them, the phase shift refers to the phase difference between the output sine wave and the input sine wave signal.

[0088] The following provides the calculation formulas for the wide-angle interference and multi-beam interference existing in the light-emitting device 10.

[0089]

[0090] Among them, formula (1) is for wide-angle interference, and formula (2) is for multi-beam interference. λ refers to the emission wavelength of the light emitted from the light-emitting layer 15, i represents the film layer between the first electrode 12 and the second electrode 17, and θ is the incident angle of the light at a film layer.

[0091] Formula (1) is used to introduce the mutual interference between the emitted light L1 and the reflected light L2. n i '(λ) refers to the refractive index of each film layer between the light-emitting layer 15 and the first electrode 12; d i ' refers to the dimension between the light-emitting layer 15 and the first electrode 12 in the first direction Y; is the phase shift of the reflected light of the first electrode 12.

[0092] Formula (2) is used to introduce the mutual interference between multiple reflected lights L2. In the microcavity structure formed by the first electrode 12 and the second electrode 17, n i (λ) refers to the refractive index of each film layer in the microcavity structure, d i is the thickness of each film layer; is the phase shift of the reflected light of the first electrode 12, is the phase shift of the reflected light of the second electrode 17.

[0093] m represents the order of resonance. When m = 1, it is called the first-order microcavity length; when m = 2, it is called the second-order microcavity length; when m = 3, it is called the third-order microcavity length. The relevant parameters of the light-emitting device 10 can be substituted into the formula to calculate the value of m, and the obtained m is the order of resonance of the light-emitting device 10. Moreover, as the thickness of each film layer in the microcavity increases, the value of m increases.

[0094] In the bottom-emitting light-emitting device, multi-beam interference is less because the light emitted from the light-emitting layer 15 rarely reflects back from the first electrode 12 with high transmittance to the second electrode 17. In the bottom-emitting light-emitting device, multi-beam interference is weak, and multi-beam interference plays a major role in enhancing light extraction by the microcavity structure. Therefore, the microcavity effect in the bottom-emitting light-emitting device is weak.

[0095] In the top-emitting light-emitting device structure, both the above-mentioned wide-angle interference and multi-beam interference exist. By appropriately adjusting the thickness and refractive index of each film layer, the microcavity resonance can be optimized. Therefore, the microcavity structure of the top-emitting light-emitting device can narrow the emission spectrum of the light-emitting device 10, making the red, green, and blue colors purer, thereby improving the purity of the light-emitting color and the light extraction efficiency of the light-emitting device 10, so that the color gamut displayed by the light-emitting device 1000 is wider. Moreover, the top-emitting light-emitting device can adjust the angular distribution of the emitted light, enhance the front light-emitting effect, and is beneficial to reducing the power consumption of small and medium-sized display applications.

[0096] The following describes Figure 3 the optical and electrical properties of the light-emitting device 10 as shown.

[0097] In some embodiments, as Figure 3 shown, the light-emitting device 10 is configured to emit green light, and the SETFOS simulation software is used to simulate the influence of the hole transport layer 14 and the electron transport layer 16 with different thicknesses on the light-emitting effect of the light-emitting device 10.

[0098] Exemplarily, the structure of the light-emitting device 10 is represented as: the first electrode 12 (ITO / Ag / ITO, 7nm / 100nm / 7nm) / hole injection layer 13 (PEDOT, 25nm) / hole transport layer 14 (PF8Cz, xnm) / light-emitting layer 15 (QD, 20nm) / electron transport layer 16 (ZnMgO, ynm) / second electrode 17 (Mg:Ag, 10nm) / light extraction layer (60nm).

[0099] The light-emitting device 10 is located on one side of the substrate 11. For example, the thickness of the substrate 11 is 0.5 mm.

[0100] It should be noted that the first electrode 12 (ITO / Ag / ITO, 7nm / 100nm / 7nm), where ITO / Ag / ITO represents the material of the first electrode 12. The first electrode 12 is a stacked structure formed by indium tin oxide (ITO) / silver (Ag) / indium tin oxide (ITO). 7nm / 100nm / 7nm represents the thickness, with the thickness of ITO being 7nm and the thickness of Ag being 100nm. The same applies to the rest of the description and will not be elaborated here.

[0101] Among them, PEDOT is the abbreviation of poly(3,4-ethylenedioxythiophene), PF8Cz is the abbreviation of poly(9,9-n-dioctyl-2,7-fluorene-alt-9-isooctyl-3,6-carbazole), and QD is the abbreviation of quantum dot.

[0102] Figure 4 It is the light output luminance diagram of the light-emitting device 10, and the color example on the left represents the light output luminance. Among them, the abscissa represents the thickness x of the hole transport layer 14, and the ordinate represents the thickness y of the electron transport layer 16. When using the SETFOS simulation software for simulation, multiple thickness data set at intervals of the electron transport layer 16 and multiple thickness data set at intervals of the hole transport layer 14 can be taken for simulation respectively. Among them, the difference between every two adjacent thickness data of the electron transport layer 16 can be equal, and the difference between every two adjacent thickness data of the hole transport layer 14 can be equal.

[0103] From Figure 4 the optical performance of the light-emitting device 10 can be seen. The thickness x of the hole transport layer 14 and the thickness y of the electron transport layer 16 are determined by the light output luminance of the light-emitting device 10.

[0104] At Figure 4 the coordinates shown, the thickness x and the thickness y in the lower left area are relatively small. At this time, the microcavity length of the light-emitting device 10 is of the first order. The yellow-green area S1 represents that the light output luminance of the light-emitting device 10 is about 6500 cd / m 2 , and this luminance is the relatively good front light output luminance of the light-emitting device 10. In the area S1, the thickness x range of the hole transport layer 14 is 20nm - 30nm, and the thickness y range of the electron transport layer 16 is 40nm - 50nm.

[0105] At Figure 4 the coordinates shown, the thickness x in the lower right area is relatively large and the thickness y is relatively small. At this time, the microcavity length of the light-emitting device 10 is of the second order. The red area S2 represents that the light output luminance of the light-emitting device 10 is about 8500 cd / m 2 , and this luminance is the relatively good front light output luminance of the light-emitting device 10. In the area S2, the thickness x range of the hole transport layer 14 is 150nm - 170nm, and the thickness y range of the electron transport layer 16 is 40nm - 70nm.

[0106] At Figure 4 the coordinates shown, the thickness x of the upper left region is relatively small and the thickness y is relatively large. At this time, the microcavity length of the light-emitting device 10 is second order. The yellow-green region S3 indicates that the light-emitting brightness of the light-emitting device 10 is approximately 6500 cd / m 2 , and this brightness is the preferable front light-emitting brightness of the light-emitting device 10. In the region S3, the thickness x range of the hole transport layer 14 is

[0107] 20 nm to 30 nm, and the thickness y range of the electron transport layer 16 is 180 nm to 200 nm.

[0108] The following provides two examples. In these two examples, the thickness x of the hole transport layer 14 is different. By varying the thickness x of the hole transport layer 14, the differences in the optical and electrical properties of the light-emitting device 10 are tested. The two examples are designated as: Example 1 and Example 2. In Example 1, the thickness of the electron transport layer 16 is 50 nm and the thickness of the hole transport layer 14 is 15 nm; in Example 2, the thickness of the electron transport layer 16 is 50 nm and the thickness of the hole transport layer 14 is 25 nm.

[0109] Figure 5 is a graph showing the relationship between the forward current efficiency and voltage of the light-emitting device 10. Among them, the abscissa represents voltage with the unit of V; the ordinate represents the forward current efficiency with the unit of cd / A. From Figure 5 it can be seen that in Example 1 where the thickness x of the hole transport layer 14 is 15 nm, within the voltage range of 2 V to 8 V, the forward current efficiency of the light-emitting device 10 can reach approximately 120 cd / A. In Example 2 where the thickness x of the hole transport layer 14 is 25 nm, within the voltage range of 2 V to 8 V, the maximum forward current efficiency of the light-emitting device 10 is approximately 100 cd / A. Therefore, when the thickness x of the hole transport layer 14 is 15 nm, the forward current efficiency of the light-emitting device 10 is larger and the light-emitting device 10 has preferable optical properties.

[0110] Figure 6 is a graph showing the relationship between the external quantum efficiency and voltage of the light-emitting device 10. Among them, the abscissa represents voltage with the unit of V; the ordinate represents the external quantum efficiency. From Figure 6 it can be seen that in Example 1 where the thickness x of the hole transport layer 14 is 15 nm, within the voltage range of 2 V to 8 V, the maximum external quantum efficiency of the light-emitting device 10 is approximately 18%. In Example 2 where the thickness x of the hole transport layer 14 is 25 nm, within the voltage range of 2 V to 8 V, the maximum external quantum efficiency of the light-emitting device 10 is approximately 26%. Therefore, when the thickness x of the hole transport layer 14 is 25 nm, the external quantum efficiency of the light-emitting device 10 is larger and the light-emitting device 10 has preferable electrical properties.

[0111] Figure 7 The light extraction angle distribution diagram of the light-emitting device 10 in Example 1, where the values outside the semi-circle represent the light extraction angles, and the dotted line indicates that the light extraction intensities on this line are equal. From Figure 7 It can be seen that the front light extraction of the light-emitting device 10 represented by Example 1 with the thickness x of the hole transport layer 14 being 15 nm is stronger. Therefore, when the thickness x of the hole transport layer 14 is 15 nm, the light-emitting device 10 has better optical performance.

[0112] Figure 8 The light extraction angle distribution diagram of the light-emitting device 10 in Example 2. From Figure 8 It can be seen that the side light extraction of the light-emitting device 10 represented by Example 2 with the thickness x of the hole transport layer 14 being 25 nm is stronger, and the front light extraction is weaker. Therefore, when the thickness x of the hole transport layer 14 is 25 nm, the light-emitting device 10 has poor optical performance.

[0113] Figure 9 The relationship curve graph of the light extraction brightness and voltage of the light-emitting device 10, where the abscissa represents the voltage with the unit of V; the ordinate represents the light extraction brightness with the unit of cd / m 2 . The light extraction brightness of the light-emitting device 10 represented by Example 1 when the thickness x of the hole transport layer 14 is 15 nm is greater than that of the light-emitting device 10 represented by Example 2 when the thickness x of the hole transport layer 14 is 25 nm. Therefore, when the thickness x of the hole transport layer 14 is 15 nm, the light-emitting device 10 has a large light extraction brightness and has better optical performance.

[0114] Therefore, through Figures 5 - 9 It can be seen that under the condition that the thickness y of the electron transport layer 16 of the light-emitting device 10 is 50 nm, when comparing the thickness x of the hole transport layer 14 being 15 nm with the thickness x of the hole transport layer 14 being 25 nm, when the thickness x of the hole transport layer 14 is 15 nm, the light-emitting device 10 has a larger front current efficiency, stronger front light extraction and larger light extraction brightness, and the light-emitting device 10 has better optical performance; when the thickness x of the hole transport layer 14 is 25 nm, the light-emitting device 10 has a larger external quantum efficiency, and the light-emitting device 10 has better electrical performance. Therefore, there is a problem of mismatch between better electrical performance and better optical performance in the setting of the film layer thickness of the light-emitting device 10.

[0115] The following introduces the influence of increasing the thickness x of the hole transport layer 14 on the optical and electrical performances of the light-emitting device 10. This example is represented as Example 3, in which the thickness y of the electron transport layer 16 is 50 nm, and the thickness x range of the hole transport layer 14 is 150 nm to 190 nm.

[0116] Figure 10The light output angle distribution diagram of the light-emitting device 10 of Example 3. From Figure 10 It can be seen that the light output from the front of the light-emitting device 10 is stronger. Therefore, by increasing the thickness x of the hole transport layer 14, the light output effect from the front of the light-emitting device 10 can be improved.

[0117] Figure 11 The relationship curve diagram of the light output brightness and voltage of the light-emitting device 10 of Example 3. From Figure 11 It can be seen that in the range of 10V to 20V of the voltage, the light output brightness range of the light-emitting device 10 is 100 cd / m 2 ~10000 cd / m 2 In Figure 9 when the voltage reaches 6V, the light output brightness of the light-emitting device 10 can reach 100000 cd / m 2 . By comparing Figure 9 and Figure 11 it can be seen that increasing the thickness x of the hole transport layer 14 results in a decrease in the light output brightness of the light-emitting device 10.

[0118] Figure 12 The relationship curve diagram of the external quantum efficiency and voltage of the light-emitting device 10 of Example 3. From Figure 12 It can be seen that in the range of 10V to 20V of the voltage, the external quantum efficiency of the light-emitting device 10 is less than 5%. In Figure 6 in Example 1 where the thickness x of the hole transport layer 14 is 15 nm, in the voltage range of 2V to 8V, the external quantum efficiency of the light-emitting device 10 is maximized to about 18%. In Example 2 where the thickness x of the hole transport layer 14 is 25 nm, in the voltage range of 2V to 8V, the external quantum efficiency of the light-emitting device 10 is maximized to about 26%. By comparing Figure 6 and Figure 12 it can be seen that increasing the thickness x of the hole transport layer 14 results in a decrease in the external quantum efficiency of the light-emitting device 10.

[0119] Therefore, increasing the thickness x of the hole transport layer 14 can improve the optical performance of the light-emitting device 10. However, it reduces the electrical performance of the light-emitting device 10, and there is a problem of mismatch between the better electrical performance and the better optical performance in the setting of the film layer thickness of the light-emitting device 10.

[0120] Based on this, as Figure 13 shown, an embodiment of the present disclosure provides a light-emitting substrate 100, and the light-emitting substrate 100 includes: a substrate 11 and a plurality of light-emitting devices 10 located on one side of the substrate 11. Each light-emitting device 10 includes a stacked first electrode 12, a light-emitting layer 15, and a second electrode 17. The first electrode 12 is closer to the substrate 11 than the second electrode 17. The first electrode 12 includes a reflective electrode, and the second electrode 17 includes a transparent electrode.

[0121] Exemplarily, the material of the light-emitting layer 15 includes quantum dots. The light-emitting substrate 100 containing quantum dots not only has the characteristics of self-luminescence and compatibility with flexible processes, but also has advantages such as a relatively narrow emission spectrum, easy adjustment of the emission wavelength, and high luminous efficiency.

[0122] Exemplarily, the first electrode 12 is a reflective electrode. The reflective electrode is used to reflect the light incident on the electrode. The material of the first electrode 12 is, for example, a metal. The first electrode 12 can be a single-layer structure or a stacked structure. For example, the first electrode 12 is a stacked structure formed by indium tin oxide (ITO) / silver (Ag) / indium tin oxide (ITO).

[0123] Exemplarily, in the wavelength range of 400 nm to 700 nm, the light transmittance of the second electrode 17 ranges from greater than or equal to 85%. For example, the material of the second electrode 17 is selected from at least one of gold, silver, magnesium silver alloy, molybdenum oxide, indium tin oxide, indium zinc oxide, indium tin zinc oxide, indium gallium oxide, and aluminum-doped zinc oxide.

[0124] Therefore, in the embodiment of the present disclosure, the light-emitting direction of the light-emitting device 10 is away from the substrate 11, and the light-emitting device 10 is a top-emission type light-emitting device.

[0125] A weak microcavity effect is formed between the first electrode 12 and the second electrode 17, and the regulation effect on the optical performance of the light-emitting device 10 is small. The film layer between the first electrode 12 and the second electrode 17 has a great influence on the electrical performance of the light-emitting device 10. The thickness of the film layer between the first electrode 12 and the second electrode 17 can be adjusted to improve the balance of carrier transport of the light-emitting device 10, thereby improving the electrical performance of the light-emitting device 10.

[0126] Exemplarily, as Figure 13 and Figure 14 shown, at least one light-emitting device 10 includes: an optical adjustment structure 110. The optical adjustment structure 110 includes: an optical regulation layer 30 and a transparent reflective layer 40. The optical regulation layer 30 is located on the side of the second electrode 17 away from the substrate 11, and the transparent reflective layer 40 is located on the side of the optical regulation layer 30 away from the substrate 11; the conductivity of the optical regulation layer 30 is less than that of the transparent reflective layer 40, and the thicknesses of the optical regulation layer 30 and the transparent reflective layer 40 are different.

[0127] It should be noted that the transparent reflective layer 40 can be used to reflect part of the light incident on the transparent reflective layer 40 and can also transmit part of the light incident on the transparent reflective layer 40.

[0128] For example, Figure 14It is a light path diagram of the light-emitting substrate 100. The light ray L4 emitted by the light-emitting layer 15 can directly pass through the transparent reflective layer 40, and the light ray L5 emitted by the light-emitting layer 15 is reflected on the transparent reflective layer 40.

[0129] Exemplarily, the material of the transparent reflective layer 40 is selected from at least one of gold, silver, magnesium-silver alloy, molybdenum oxide, tungsten oxide, zinc sulfide, indium tin oxide, indium gallium oxide, aluminum-doped zinc oxide, silver nanowires, copper nanowires, and carbon nanotubes. The material of the transparent reflective layer 40 is a conductor, and the transparent reflective layer 40 has a relatively large conductivity.

[0130] Exemplarily, the thickness range of the transparent reflective layer 40 is 10 nm to 100 nm. For example, when the material of the transparent reflective layer 40 includes magnesium-silver alloy, the thickness range of the transparent reflective layer 40 is 10 nm to 20 nm. When the material of the transparent reflective layer 40 includes indium tin oxide, indium gallium oxide, and aluminum-doped zinc oxide, the thickness range of the transparent reflective layer 40 is 50 nm to 100 nm. When the material of the transparent reflective layer 40 includes molybdenum oxide and tungsten oxide, the thickness range of the transparent reflective layer 40 is 10 nm to 50 nm. When the material of the transparent reflective layer 40 includes silver nanowires, copper nanowires, and carbon nanotubes, the thickness range of the transparent reflective layer 40 is 20 nm to 50 nm.

[0131] Exemplarily, the material of the optical modulation layer 30 is selected from at least one of 4,4,4,-tris(carbazol-9-yl)triphenylamine, N,N'-diphenyl-N,N'-(1-naphthyl)-1,1'-biphenyl-4,4'-diamine, 4,4'-bis(9-carbazolyl)biphenyl, silicon oxide, silicon nitride, and silicon oxynitride. The material of the optical modulation layer 30 is an insulator, and the optical modulation layer 30 has a relatively small conductivity.

[0132] From the comparison of the materials of the transparent reflective layer 40 and the optical modulation layer 30, it can be seen that the conductivity of the optical modulation layer 30 is less than that of the transparent reflective layer 40. Moreover, in the preparation methods of the transparent reflective layer 40 and the optical modulation layer 30, the transparent reflective layer 40 can be formed by evaporation coating, and the optical modulation layer 30 can be formed by deposition. Generally, the film thickness formed by evaporation coating is thinner than that formed by deposition. Therefore, the thickness of the transparent reflective layer 40 is generally less than that of the optical modulation layer 30.

[0133] Exemplarily, such as Figure 14As shown, the first electrode 12 includes a reflective electrode. The transparent reflective layer 40 can be used to reflect part of the light incident on the transparent reflective layer 40 and also transmit part of the light incident on the transparent reflective layer 40. The light L4 emitted by the light-emitting layer 15 can be directly emitted from the transparent reflective layer 40; the light L6 emitted by the light-emitting layer 15 can be reflected by the first electrode 12 to the transparent reflective layer 40; the light L5 emitted by the light-emitting layer 15 can be reflected by the transparent reflective layer 40 to the first electrode 12, and this light is denoted as L7. The light L7 can be reflected by the first electrode 12 to the transparent reflective layer 40; the light reflected by the first electrode 12 is denoted as the light L8. The interference between the light L5 and the light L8 is wide-angle interference, and the interference between multiple lights L8 is multi-beam interference. Therefore, a strong microcavity is formed between the first electrode 12 and the transparent reflective layer 40.

[0134] In the embodiments of the present disclosure, through the setting of the transparent reflective layer 40, a strong microcavity effect is formed between the first electrode 12 and the transparent reflective layer 40. The light-emitting layer 15 is located between the transparent reflective layer 40 and the first electrode 12, that is, the light-emitting layer 15 is located in the microcavity. Due to the microcavity effect, the intensity of light with a certain wavelength emitted by the light-emitting layer 15 will be increased to improve the luminous efficiency of the light-emitting device 10.

[0135] Moreover, the cavity length of the microcavity can be adjusted by adjusting the thickness of the optical control layer 30. Since the optical control layer 30 is located between the transparent reflective layer 40 and the second electrode 17, the setting of the optical control layer 30 will not affect the electrical performance of the light-emitting device 10. For example, after adjusting the thicknesses of the respective film layers between the first electrode 12 and the second electrode 17 to be relatively optimal for the electrical performance of the light-emitting device 10, the thickness of the optical control layer 30 is adjusted to be relatively optimal for the optical performance of the light-emitting device 10.

[0136] Therefore, in the embodiments of the present disclosure, by providing the optical adjustment structure 110 on the side of the second electrode 17 away from the substrate 11, the purpose of separately adjusting the optical performance and the electrical performance of the light-emitting device 10 is achieved, so that the light-emitting device 10 has relatively optimal electrical performance and optical performance.

[0137] Furthermore, when the thicknesses of the respective film layers between the first electrode 12 and the second electrode 17 are relatively thin, the second-order microcavity effect of the light-emitting device 10 can be achieved by increasing the thickness of the optical control layer 30, so that the light-emitting device 10 has a strong luminous intensity and relatively optimal optical performance.

[0138] In some embodiments, as Figure 13 shown, the light transmittance of the optical control layer 30 is greater than or equal to the light transmittance of the transparent reflective layer 40.

[0139] It should be noted that the light transmittance refers to the ratio of the transmitted light flux to the incident light flux during the process of the incident light passing from the irradiated surface of the film layer to the other surface opposite to the irradiated surface of the film layer. For example, the light transmittance of the film layer can be measured by an ultraviolet-visible absorption spectrometer.

[0140] Exemplarily, the light transmittance of the optical modulation layer 30 ranges from greater than or equal to 90%. For example, the light transmittance of the optical modulation layer 30 is 90%, 92%, 93%, 96%, 97%, 98%, 99% or 100%, etc., and there is no limit here.

[0141] By setting the light transmittance of the optical modulation layer 30 to be greater than or equal to 90%, while the optical modulation layer 30 has the function of adjusting the microcavity length, the optical modulation layer 30 has a relatively high light transmittance to ensure that the light-emitting device 10 has a relatively high light output intensity.

[0142] Exemplarily, the light transmittance of the transparent reflective layer 40 ranges from greater than or equal to 60% and less than or equal to 90%. In this way, the transparent reflective layer 40 can be used to reflect part of the light incident on the transparent reflective layer 40 and also transmit part of the light incident on the transparent reflective layer 40.

[0143] By setting the light transmittance of the optical modulation layer 30 to be greater than or equal to the light transmittance of the transparent reflective layer 40, the light can pass through the optical modulation layer 30 and further transmit or reflect at the transparent reflective layer 40, so that the light interferes to improve the optical performance of the light-emitting device 10.

[0144] In some embodiments, as Figure 13 shown, the extinction coefficient of the optical modulation layer 30 ranges from 0.001m -1 to 0.005m -1 .

[0145] Exemplarily, the extinction coefficient of the optical modulation layer 30 is 0.001m -1 , 0.002m -1 , 0.003m -1 , 0.004m -1 or 0.005m -1 etc., and there is no limit here.

[0146] It should be noted that the extinction coefficient reflects the absorption of light by the film layer. When the extinction coefficient is relatively large, it means that the film layer will absorb part of the light, resulting in a decrease in the transmittance of the film layer. For example, the extinction coefficient of the film layer can be measured by an ellipsometer.

[0147] By setting the extinction coefficient of the optical modulation layer 30 to range from 0.001m -1 to 0.005m-1 is set to ensure that the optical modulation layer 30 has a small extinction coefficient, so that the optical modulation layer 30 has a high light transmittance.

[0148] In some embodiments, such as Figure 13 and Figure 15 shown, the plurality of light-emitting devices 10 include: a first light-emitting device 101 configured to emit first-color light; the optical modulation layer 30 includes: a first modulation portion 301, and the first modulation portion 301 is correspondingly arranged with the first light-emitting device 101; wherein, the thickness d2 of the first modulation portion 301 ranges from 55 nm to 65 nm.

[0149] Exemplarily, the first-color light is configured to be green light.

[0150] It should be noted that the thickness d2 of the first modulation portion 301 is the dimension of the first modulation portion 301 in the first direction Y, and the first direction Y is perpendicular to the substrate 11.

[0151] Exemplarily, the thickness d2 of the first modulation portion 301 is 55 nm, 57 nm, 59 nm, 60 nm, 61 nm, 62 nm, 64 nm or 65 nm, etc., and there is no limitation here.

[0152] By setting the thickness d2 of the first modulation portion 301 to range from 55 nm to 65 nm, the first modulation portion 301 can adjust the cavity length of the microcavity between the first electrode 12 of the first light-emitting device 101 and the transparent reflective layer 40, increasing the mutual interference effect between the light rays, so that the first light-emitting device 101 has a strong light-emitting brightness. For the content of the light-emitting brightness, specifically refer to the introduction of the light-emitting brightness diagram of the first light-emitting device 101 in the following Figure 15 and the content is not described in detail here.

[0153] In some embodiments, such as Figure 13 and Figure 15 shown, the light-emitting substrate 100 further includes: a light extraction layer 18, and the light extraction layer 18 is located on the side of the transparent reflective layer 40 away from the substrate 11; the light extraction layer 18 includes: a first light extraction portion 181, and the first light extraction portion 181 is correspondingly arranged with the first light-emitting device 101. Wherein, the thickness d3 of the first light extraction portion 181 ranges from 85 nm to 115 nm.

[0154] Exemplarily, the thickness d3 of the first light extraction portion 181 is 85 nm, 90 nm, 95 nm, 100 nm, 105 nm, 110 nm or 115 nm, etc., and there is no limitation here.

[0155] It should be noted that the difference in the refractive index of the transparent reflective layer 40 for light and the refractive index of air for light is relatively large, so total internal reflection will occur between the transparent reflective layer 40 and air, resulting in a decrease in the light extraction efficiency of the light-emitting device 10. Therefore, a light extraction layer 18 can be provided on the side of the transparent reflective layer 40 away from the substrate 11, and the refractive index of the light extraction layer 18 for light is between the refractive index of the transparent reflective layer 40 for light and the refractive index of air for light. This can reduce the total internal reflection of light at the interface between the transparent reflective layer 40 and the light extraction layer 18, as well as at the interface between the light extraction layer 18 and air, which is beneficial for light extraction and can improve the light extraction efficiency of the light-emitting device 10.

[0156] Therefore, the setting of the light extraction layer 18 can improve the front light extraction effect of the light-emitting device 10. Further, by setting the thickness d3 of the first light extraction portion 181 in the range of 85 nm to 115 nm, the setting of the first light extraction portion 181 can further increase the front light extraction of the first light-emitting device 101, so that the first light-emitting device 101 has a strong light extraction brightness. For the content of the light extraction brightness, specifically refer to the following introduction of the Figure 15 light extraction brightness diagram of the first light-emitting device 101.

[0157] Figure 15 is the light extraction brightness diagram of the first light-emitting device 101, where the abscissa represents the thickness d2 of the first adjustment portion 301, and the ordinate represents the thickness d3 of the first light extraction portion 181. As Figure 13 shown, the structure of the first light-emitting device 101 is expressed as: the first electrode 12 (ITO / Ag / ITO, 7 nm / 100 nm / 7 nm) / hole injection layer 13 (PEDOT, 25 nm) / hole transport layer 14 (PF8Cz, 25 nm) / light-emitting layer 15 (QD, 20 nm) / electron transport layer 16 (ZnMgO, 50 nm) / second electrode 17 (ITO, 50 nm) / first adjustment portion 301 (d2) / transparent reflective layer 40 (Mg:Ag, 10 nm) / first light extraction portion 181 (d3).

[0158] From Figure 15 it can be seen that the red region S4 represents that the light extraction brightness of the first light-emitting device 101 is approximately 9000 cd / m 2 , and this brightness is the better front light extraction brightness of the first light-emitting device 101. In the region S4, the thickness d2 of the first adjustment portion 301 ranges from 55 nm to 65 nm, and the thickness d3 of the first light extraction portion 181 ranges from 85 nm to 115 nm.

[0159] Therefore, by setting the thickness range of the first control unit 301 to be 55 nm to 65 nm and the thickness range of the first light extraction unit 181 to be 85 nm to 115 nm, the first light-emitting device 101 can have a strong light-emitting brightness.

[0160] In some embodiments, as Figure 16 and Figure 17 shown, the first light-emitting device 101 further includes: a first hole transport layer 141; the first hole transport layer 141 is located between the first electrode 12 and the light-emitting layer 15 of the first light-emitting device 101, or the first hole transport layer 141 is located between the light-emitting layer 15 and the second electrode 17 of the first light-emitting device 101; wherein, the thickness d4 of the first hole transport layer 141 ranges from 20 nm to 30 nm.

[0161] Exemplarily, as Figure 16 shown, the first hole transport layer 141 is located between the first electrode 12 and the light-emitting layer 15 of the first light-emitting device 101. At this time, the first electrode 12 of the first light-emitting device 101 is an anode, and the second electrode 17 of the first light-emitting device 101 is a cathode.

[0162] Exemplarily, as Figure 17 shown, the first hole transport layer 141 is located between the light-emitting layer 15 and the second electrode 17 of the first light-emitting device 101. At this time, the first electrode 12 of the first light-emitting device 101 is a cathode, and the second electrode 17 of the first light-emitting device 101 is an anode.

[0163] Exemplarily, the thickness d4 of the first hole transport layer 141 is 20 nm, 21 nm, 22 nm, 23 nm, 25 nm, 26 nm, 27 nm, 28 nm, 29 nm or 30 nm, etc., and there is no limitation here.

[0164] By setting the thickness d4 of the first hole transport layer 141 to range from 20 nm to 30 nm, the hole transport performance of the first light-emitting device 101 can be improved, which is beneficial to improving the electrical performance of the first light-emitting device 101.

[0165] In some embodiments, as Figure 18 and Figure 19 shown, the first light-emitting device 101 further includes: a first electron transport layer 161; the first electron transport layer 161 is located between the first electrode 12 and the light-emitting layer 15 of the first light-emitting device 101, or the first electron transport layer 161 is located between the light-emitting layer 15 and the second electrode 17 of the first light-emitting device 101; wherein, the thickness d5 of the first electron transport layer 161 ranges from 30 nm to 70 nm.

[0166] Exemplarily, as Figure 18As shown, the first electron transport layer 161 is located between the first electrode 12 of the first light-emitting device 101 and the light-emitting layer 15 of the first light-emitting device 101. At this time, the first electrode 12 of the first light-emitting device 101 is the cathode, and the second electrode 17 of the first light-emitting device 101 is the anode.

[0167] Exemplarily, as Figure 19 shown, the first electron transport layer 161 is located between the light-emitting layer 15 of the first light-emitting device 101 and the second electrode 17 of the first light-emitting device 101. At this time, the first electrode 12 of the first light-emitting device 101 is the anode, and the second electrode 17 of the first light-emitting device 101 is the cathode.

[0168] Exemplarily, the thickness d5 of the first electron transport layer 161 is 30nm, 35nm, 40nm, 45nm, 50nm, 55nm, 60nm or 70nm, etc., and there is no limitation here.

[0169] By setting the thickness d5 range of the first electron transport layer 161 to be 30nm to 70nm, the electron transport performance of the first light-emitting device 101 can be improved, which is beneficial to improving the electrical performance of the first light-emitting device 101.

[0170] In some embodiments, such as Figure 13 and Figure 20 shown, the first light-emitting device 101 further includes: a first hole transport layer 141 and a first electron transport layer 161; the first electrode 12, the first hole transport layer 141, the light-emitting layer 15 of the first light-emitting device 101, the first electron transport layer 161 and the second electrode 17 of the first light-emitting device 101 are arranged in a direction away from the substrate 11; or, the first electrode 12, the first electron transport layer 161, the light-emitting layer 15 of the first light-emitting device 101, the first hole transport layer 141 and the second electrode 17 of the first light-emitting device 101 are arranged in a direction away from the substrate 11. Among them, the thickness d4 range of the first hole transport layer 141 is 20nm to 30nm; the thickness d5 range of the first electron transport layer 161 is 30nm to 70nm.

[0171] Exemplarily, as Figure 13 shown, the first electrode 12, the first hole transport layer 141, the light-emitting layer 15 of the first light-emitting device 101, the first electron transport layer 161 and the second electrode 17 of the first light-emitting device 101 are arranged in a direction away from the substrate 11. At this time, the first electrode 12 of the first light-emitting device 101 is the anode, and the second electrode 17 of the first light-emitting device 101 is the cathode.

[0172] Exemplarily, as Figure 20As shown, the first electrode 12 of the first light-emitting device 101, the first electron transport layer 161, the light-emitting layer 15 of the first light-emitting device 101, the first hole transport layer 141 and the second electrode 17 of the first light-emitting device 101 are arranged in a direction away from the substrate 11. At this time, the first electrode 12 of the first light-emitting device 101 is a cathode, and the second electrode 17 of the first light-emitting device 101 is an anode.

[0173] By setting the thickness d4 of the first hole transport layer 141 to a range of 20nm to 30nm, and the thickness d5 of the first electron transport layer 161 to a range of 30nm to 70nm, the transport performance of holes and electrons in the first light-emitting device 101 can be improved, and the balance of electron and hole transport can be improved, which is beneficial to improving the electrical performance of the first light-emitting device 101.

[0174] In some embodiments, Figure 13 and Figure 21 As shown, the multiple light-emitting devices 10 include: a second light-emitting device 102, which is configured to emit a second color light; the optical regulation layer 30 includes: a second regulation part 302, which is arranged corresponding to the second light-emitting device 102; wherein the thickness d6 of the second regulation part 302 ranges from 95nm to 115nm.

[0175] Exemplarily, the second color light is configured as red light.

[0176] Exemplarily, the thickness d6 of the second regulating portion 302 is 95 nm, 97 nm, 98 nm, 100 nm, 102 nm, 105 nm, 110 nm or 115 nm, etc., which is not limited here.

[0177] By setting the thickness d6 of the second regulating portion 302 to be in the range of 95 nm to 115 nm, the second regulating portion 302 can adjust the cavity length of the microcavity between the first electrode 12 of the second light-emitting device 102 and the transparent reflective layer 40, increase the mutual interference between the light rays, so that the second light-emitting device 102 has a stronger light output brightness. For details about the light output brightness, refer to the following description. Figure 21 The contents of the light output brightness diagram of the second light-emitting device 102 are not described in detail here.

[0178] In some embodiments, Figure 13 and Figure 21 As shown, the light-emitting substrate 100 also includes: a light extraction layer 18, which is located on the side of the transparent reflective layer 40 away from the substrate 11; the light extraction layer 18 includes: a second light extraction portion 182, which is arranged corresponding to the second light-emitting device 102; wherein, the thickness d7 of the second light extraction portion 182 ranges from 105nm to 145nm.

[0179] Exemplarily, the thickness d7 of the second light extraction portion 182 is 105 nm, 110 nm, 115 nm, 120 nm, 125 nm, 130 nm, 135 nm, 140 nm or 145 nm, etc., which is not limited here.

[0180] By setting the second light extraction portion 182 and the thickness d7 of the second light extraction portion 182 in the range of 105nm to 145nm, the total reflection of light at the interface between the transparent reflective layer 40 and the second light extraction portion 182 and the interface between the second light extraction portion 182 and the air can be reduced, which is beneficial to light extraction and can increase the front light output of the second light emitting device 102, so that the second light emitting device 102 has a stronger light output brightness. For details about the light output brightness, please refer to the following Figure 21 The contents of the light output brightness diagram of the second light-emitting device 102 are introduced.

[0181] Figure 21 : is a light output brightness diagram of the second light emitting device 102, wherein the abscissa represents the thickness d6 of the second regulating portion 302, and the ordinate represents the thickness d7 of the second light extraction portion 182. Figure 13 As shown, the structure of the second light-emitting device 102 is represented as: first electrode 12 (ITO / Ag / ITO, 7nm / 100nm / 7nm) / hole injection layer 13 (PEDOT, 25nm) / hole transport layer 14 (PF8Cz, 25nm) / light-emitting layer 15 (QD, 20nm) / electron transport layer 16 (ZnMgO, 50nm) / second electrode 17 (ITO, 50nm) / second regulating part 302 (d6) / transparent reflective layer 40 (Mg: Ag, 10nm) / second light extraction part 182 (d7).

[0182] from Figure 21 It can be seen that the red area S5 indicates that the light output brightness of the second light emitting device 102 is about 3500 cd / m 2 , which is the preferred front light emitting brightness of the second light emitting device 102. In region S5, the thickness d6 of the second regulating portion 302 ranges from 95nm to 115nm, and the thickness d7 of the second light extraction portion 182 ranges from 105nm to 145nm.

[0183] Therefore, by setting the thickness d6 of the second regulating portion 302 to be in the range of 95nm to 115nm and the thickness d7 of the second light extraction portion 182 to be in the range of 105nm to 145nm, the second light emitting device 102 can have a stronger light output brightness.

[0184] In some embodiments, Figure 16 and Figure 17As shown, the second light-emitting device 102 further includes: a second hole transport layer 142; the second hole transport layer 142 is located between the first electrode 12 of the second light-emitting device 102 and the light-emitting layer 15 of the second light-emitting device 102, or the second hole transport layer 142 is located between the light-emitting layer 15 of the second light-emitting device 102 and the second electrode 17 of the second light-emitting device 102; wherein, the thickness d8 of the second hole transport layer 142 ranges from 20 nm to 30 nm.

[0185] Exemplarily, as Figure 16 shown, the second hole transport layer 142 is located between the first electrode 12 of the second light-emitting device 102 and the light-emitting layer 15 of the second light-emitting device 102. At this time, the first electrode 12 of the second light-emitting device 102 is an anode, and the second electrode 17 of the second light-emitting device 102 is a cathode.

[0186] Exemplarily, as Figure 17 shown, the second hole transport layer 142 is located between the light-emitting layer 15 of the second light-emitting device 102 and the second electrode 17 of the second light-emitting device 102. At this time, the first electrode 12 of the second light-emitting device 102 is a cathode, and the second electrode 17 of the second light-emitting device 102 is an anode.

[0187] Exemplarily, the thickness d8 of the second hole transport layer 142 is 20 nm, 21 nm, 22 nm, 23 nm, 25 nm, 26 nm, 27 nm, 28 nm, 29 nm or 30 nm, etc., and there is no limitation here.

[0188] By setting the thickness d8 of the second hole transport layer 142 to range from 20 nm to 30 nm, the hole transport performance of the second light-emitting device 102 can be improved, which is beneficial to improving the electrical performance of the second light-emitting device 102.

[0189] In some embodiments, as Figure 18 and Figure 19 shown, the second light-emitting device 102 further includes: a second electron transport layer 162; the second electron transport layer 162 is located between the first electrode 12 of the second light-emitting device 102 and the light-emitting layer 15 of the second light-emitting device 102; or, the second electron transport layer 162 is located between the light-emitting layer 15 of the second light-emitting device 102 and the second electrode 17 of the second light-emitting device 102; wherein, the thickness d9 of the second electron transport layer 162 ranges from 30 nm to 70 nm.

[0190] Exemplarily, as Figure 18 shown, the second electron transport layer 162 is located between the first electrode 12 of the second light-emitting device 102 and the light-emitting layer 15 of the second light-emitting device 102. At this time, the first electrode 12 of the second light-emitting device 102 is a cathode, and the second electrode 17 of the second light-emitting device 102 is an anode.

[0191] Exemplarily, as Figure 19 shown, the second electron transport layer 162 is located between the light-emitting layer 15 of the second light-emitting device 102 and the second electrode 17 of the second light-emitting device 102. At this time, the first electrode 12 of the second light-emitting device 102 is the anode, and the second electrode 17 of the second light-emitting device 102 is the cathode.

[0192] Exemplarily, the thickness d9 of the second electron transport layer 162 is 30 nm, 35 nm, 40 nm, 45 nm, 50 nm, 55 nm, 60 nm, 70 nm, etc., and there is no limitation here.

[0193] By setting the thickness d9 range of the second electron transport layer 162 to be 30 nm to 70 nm, the electron transport performance of the second light-emitting device 102 can be improved, which is beneficial to improving the electrical performance of the second light-emitting device 102.

[0194] In some embodiments, as Figure 13 and Figure 20 shown, the second light-emitting device 102 further includes: a second hole transport layer 142 and a second electron transport layer 162; the first electrode 12, the second hole transport layer 142, the light-emitting layer 15 of the second light-emitting device 102, the second electron transport layer 162, and the second electrode 17 of the second light-emitting device 102 are arranged in a direction away from the substrate 11; or, the first electrode 12, the second electron transport layer 162, the light-emitting layer 15 of the second light-emitting device 102, the second hole transport layer 142, and the second electrode 17 of the second light-emitting device 102 are arranged in a direction away from the substrate 11; wherein, the thickness d8 range of the second hole transport layer 142 is 20 nm to 30 nm; the thickness d9 range of the second electron transport layer 162 is 30 nm to 70 nm.

[0195] Exemplarily, as Figure 13 shown, the first electrode 12, the second hole transport layer 142, the light-emitting layer 15 of the second light-emitting device 102, the second electron transport layer 162, and the second electrode 17 of the second light-emitting device 102 are arranged in a direction away from the substrate 11. At this time, the first electrode 12 of the second light-emitting device 102 is the anode, and the second electrode 17 of the second light-emitting device 102 is the cathode.

[0196] Exemplarily, as Figure 20 shown, the first electrode 12, the second electron transport layer 162, the light-emitting layer 15 of the second light-emitting device 102, the second hole transport layer 142, and the second electrode 17 of the second light-emitting device 102 are arranged in a direction away from the substrate 11. At this time, the first electrode 12 of the second light-emitting device 102 is the cathode, and the second electrode 17 of the second light-emitting device 102 is the anode.

[0197] By setting the thickness d8 of the second hole transport layer 142 to a range of 20nm to 30nm, and the thickness d9 of the second electron transport layer 162 to a range of 30nm to 70nm, the transport performance of holes and electrons in the second light-emitting device 102 can be improved, and the balance of electron and hole transport can be improved, which is beneficial to improving the electrical performance of the second light-emitting device 102.

[0198] In some embodiments, Figure 13 and Figure 22 As shown, the multiple light-emitting devices 10 include: a third light-emitting device 103, which is configured to emit a third color light; the optical regulation layer 30 includes: a third regulation part 303, which is arranged corresponding to the third light-emitting device 103; wherein the thickness d10 of the third regulation part 303 ranges from 5nm to 15nm.

[0199] Exemplarily, the third color light is configured as blue light.

[0200] Exemplarily, the thickness d10 of the third regulating portion 303 is 5 nm, 6 nm, 7 nm, 8 nm, 9 nm, 10 nm, 12 nm or 15 nm, etc., which is not limited here.

[0201] By setting the thickness d10 of the third regulating portion 303 to be in the range of 5 nm to 15 nm, the third regulating portion 303 can adjust the cavity length of the microcavity between the first electrode 12 of the third light-emitting device 103 and the transparent reflective layer 40, increase the mutual interference between the light rays, so that the third light-emitting device 103 has a stronger light output brightness. For details about the light output brightness, refer to the following description. Figure 22 The contents of the light output brightness diagram of the third light-emitting device 103 are not described in detail here.

[0202] In some embodiments, Figure 13 and Figure 22 As shown, the light-emitting substrate 100 also includes: a light extraction layer 18, which is located on the side of the transparent reflective layer 40 away from the substrate 11; the light extraction layer 18 includes: a third light extraction portion 183, which is arranged corresponding to the third light-emitting device 103; wherein, the thickness d11 of the third light extraction portion 183 ranges from 55nm to 85nm.

[0203] Exemplarily, the thickness d11 of the third light extraction portion 183 is 55 nm, 60 nm, 65 nm, 70 nm, 75 nm, 80 nm or 85 nm, etc., which is not limited here.

[0204] By providing the third light extraction portion 183 and setting the thickness d11 of the third light extraction portion 183 within the range of 55 nm to 85 nm, total reflection of light at the interface between the transparent reflective layer 40 and the third light extraction portion 183 and at the interface between the third light extraction portion 183 and air can be reduced, which is beneficial to light extraction. It can increase the front light emission of the third light-emitting device 103, so that the third light-emitting device 103 has a strong light emission brightness. For the content regarding the light emission brightness, specifically refer to the following introduction of the Figure 22 light emission brightness diagram of the third light-emitting device 103.

[0205] Figure 22 FIG. is the light emission brightness diagram of the third light-emitting device 103, where the abscissa represents the thickness d10 of the third regulation portion 303 and the ordinate represents the thickness d11 of the third light extraction portion 183. As Figure 13 shown, the structure of the third light-emitting device 103 is represented as: the first electrode 12 (ITO / Ag / ITO, 7 nm / 100 nm / 7 nm) / hole injection layer 13

[0206] (PEDOT, 25 nm) / hole transport layer 14 (PF8Cz, 25 nm) / light-emitting layer 15 (QD, 20 nm) / electron transport layer 16 (ZnMgO, 50 nm) / second electrode 17 (ITO, 50 nm) / third regulation portion 303 (d10) / transparent reflective layer 40 (Mg:Ag, 10 nm) / third light extraction portion 183 (d11).

[0207] It can be seen from Figure 22 that the red region S6 represents that the light emission brightness of the third light-emitting device 103 is approximately 170 cd / m 2 , which is the relatively optimal front light emission brightness of the third light-emitting device 103. In the region S6, the thickness d10 of the third regulation portion 303 ranges from 5 nm to 15 nm, and the thickness d11 of the third light extraction portion 183 ranges from 55 nm to 85 nm.

[0208] Therefore, by setting the thickness d10 of the third regulation portion 303 within the range of 5 nm to 15 nm and setting the thickness d11 of the third light extraction portion 183 within the range of 55 nm to 85 nm, the third light-emitting device 103 can have a strong light emission brightness.

[0209] In some embodiments, such as Figure 16 and Figure 17As shown, the third light-emitting device 103 further includes: a third hole transport layer 143; the third hole transport layer 143 is located between the first electrode 12 of the third light-emitting device 103 and the light-emitting layer 15 of the third light-emitting device 103; or, the third hole transport layer 143 is located between the light-emitting layer 15 of the third light-emitting device 103 and the second electrode 17 of the third light-emitting device 103; wherein, the thickness d12 of the third hole transport layer 143 ranges from 20 nm to 40 nm.

[0210] Exemplarily, as Figure 16 shown, the third hole transport layer 143 is located between the first electrode 12 of the third light-emitting device 103 and the light-emitting layer 15 of the third light-emitting device 103. At this time, the first electrode 12 of the third light-emitting device 103 is the anode, and the second electrode 17 of the third light-emitting device 103 is the cathode.

[0211] Exemplarily, as Figure 17 shown, the third hole transport layer 143 is located between the light-emitting layer 15 of the third light-emitting device 103 and the second electrode 17 of the third light-emitting device 103. At this time, the first electrode 12 of the third light-emitting device 103 is the cathode, and the second electrode 17 of the third light-emitting device 103 is the anode.

[0212] Exemplarily, the thickness d12 of the third hole transport layer 143 is 20 nm, 23 nm, 25 nm, 27 nm, 30 nm, 32 nm, 35 nm, 37 nm, 39 nm or 40 nm, etc., and there is no limit here.

[0213] By setting the thickness d12 of the third hole transport layer 143 to range from 20 nm to 40 nm, the hole transport performance of the third light-emitting device 103 can be improved, which is beneficial to improving the electrical performance of the third light-emitting device 103.

[0214] In some embodiments, as Figure 18 and Figure 19 shown, the third light-emitting device 103 further includes: a third electron transport layer 163; the third electron transport layer 163 is located between the first electrode 12 of the third light-emitting device 103 and the light-emitting layer 15 of the third light-emitting device 103; or, the third electron transport layer 163 is located between the light-emitting layer 15 of the third light-emitting device 103 and the second electrode 17 of the third light-emitting device 103; wherein, the thickness d13 of the third electron transport layer 163 ranges from 40 nm to 80 nm.

[0215] Exemplarily, as Figure 18 shown, the third electron transport layer 163 is located between the first electrode 12 of the third light-emitting device 103 and the light-emitting layer 15 of the third light-emitting device 103. At this time, the first electrode 12 of the third light-emitting device 103 is the cathode, and the second electrode 17 of the third light-emitting device 103 is the anode.

[0216] Exemplarily, such as Figure 19 As shown, the third electron transport layer 163 is located between the light-emitting layer 15 of the third light-emitting device 103 and the second electrode 17 of the third light-emitting device 103. At this time, the first electrode 12 of the third light-emitting device 103 is the anode, and the second electrode 17 of the third light-emitting device 103 is the cathode.

[0217] Exemplarily, the thickness d13 of the third electron transport layer 163 is 40nm, 45nm, 50nm, 55nm, 60nm, 65nm, 70nm or 80nm, etc., and there is no limitation here.

[0218] By setting the thickness d13 range of the third electron transport layer 163 to be 40nm to 80nm, the electron transport performance of the third light-emitting device 103 can be improved, which is beneficial to improving the electrical performance of the third light-emitting device 103.

[0219] In some embodiments, such as Figure 13 and Figure 20 As shown, the third light-emitting device 103 further includes: a third hole transport layer 143 and a third electron transport layer 163; the first electrode 12, the third hole transport layer 143, the light-emitting layer 15 of the third light-emitting device 103, the third electron transport layer 163 and the second electrode 17 of the third light-emitting device 103 are arranged in a direction away from the substrate 11; or, the first electrode 12, the third electron transport layer 163, the light-emitting layer 15 of the third light-emitting device 103, the third hole transport layer 143 and the second electrode 17 of the third light-emitting device 103 are arranged in a direction away from the substrate 11; wherein, the thickness d12 range of the third hole transport layer 143 is 20nm to 40nm; the thickness d13 range of the third electron transport layer 163 is 40nm to 80nm.

[0220] Exemplarily, such as Figure 13 As shown, the first electrode 12, the third hole transport layer 143, the light-emitting layer 15 of the third light-emitting device 103, the third electron transport layer 163 and the second electrode 17 of the third light-emitting device 103 are arranged in a direction away from the substrate 11. At this time, the first electrode 12 of the third light-emitting device 103 is the anode, and the second electrode 17 of the third light-emitting device 103 is the cathode.

[0221] Exemplarily, such as Figure 20As shown, the first electrode 12, the third electron transport layer 163, the light-emitting layer 15 of the third light-emitting device 103, the third hole transport layer 143, and the second electrode 17 of the third light-emitting device 103 are arranged in a direction away from the substrate 11. At this time, the first electrode 12 of the third light-emitting device 103 is the cathode, and the second electrode 17 of the third light-emitting device 103 is the anode.

[0222] By setting the thickness d12 of the third hole transport layer 143 in the range of 20 nm to 40 nm and the thickness d13 of the third electron transport layer 163 in the range of 40 nm to 80 nm, the hole and electron transport performance of the third light-emitting device 103 can be improved, and the electron and hole transport balance can be improved, which is beneficial to improving the electrical performance of the third light-emitting device 103.

[0223] In some embodiments, as Figure 13 shown, the light-emitting device 10 further includes: a hole injection layer 13, and the hole injection layer 13 is located on the side of the hole transport layer 14 away from the light-emitting layer 15.

[0224] By setting the hole injection layer 13, the hole injection ability of the light-emitting device 10 can be improved, and the electrical performance of the light-emitting device 10 can be improved.

[0225] Exemplarily, the light-emitting device 10 further includes at least one of an electron blocking layer, a hole blocking layer, and an electron injection layer. For example, the electron blocking layer is located between the hole transport layer 14 and the light-emitting layer 15, the hole blocking layer is located on the side of the electron transport layer 16 close to the light-emitting layer 15, and the electron injection layer is located on the side of the electron transport layer 16 away from the light-emitting layer 15.

[0226] By setting the electron injection layer, the electron injection ability of the light-emitting device 10 can be improved. By setting the electron blocking layer and the hole blocking layer, the balance of electron and hole transport of the light-emitting device 10 can be further improved, which is beneficial to improving the electrical performance of the light-emitting device 10.

[0227] As Figure 1 shown, the light-emitting device 1000 provided by some embodiments of the present disclosure includes the light-emitting substrate 100 as described in any one of the above embodiments.

[0228] Of course, the light-emitting device 1000 may further include other components. For example, it may include a driving chip for providing an electrical signal to the light-emitting substrate 100 to drive the light-emitting substrate 100 to emit light, and the chip may be a circuit board and / or an integrated circuit (IC).

[0229] In some embodiments, the light-emitting device 1000 may be a lighting device. In this case, the light-emitting device 1000 serves as a light source to achieve the lighting function. For example, the light-emitting device 1000 may be a backlight module in a liquid crystal display device, a lamp for internal or external lighting, or various signal lights, etc.

[0230] In other embodiments, the light-emitting device 1000 may be a display device. In this case, the light-emitting substrate 100 is a display substrate for achieving the function of displaying an image (i.e., a picture).

[0231] As described above, the above are only specific embodiments of the present disclosure, but the protection scope of the present disclosure is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present disclosure who thinks of changes or substitutions should be covered within the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure should be subject to the protection scope of the claims.

Claims

1. A light-emitting substrate, characterized in that: include: substrate; A plurality of light-emitting devices are located on one side of the substrate, each of the light-emitting devices comprises a stacked first electrode, a light-emitting layer, and a second electrode, wherein the first electrode is closer to the substrate than the second electrode; The first electrode comprises a reflective electrode, and the second electrode comprises a transparent electrode; Among them, at least one of the light-emitting devices includes: an optical adjustment structure, the optical adjustment structure includes an optical adjustment layer and a transparent reflective layer, the optical adjustment layer is located on the side of the second electrode away from the substrate, and the transparent reflective layer is located on the side of the optical adjustment layer away from the substrate; the conductivity of the optical adjustment layer is less than the conductivity of the transparent reflective layer, and the thickness of the optical adjustment layer is different from that of the transparent reflective layer.

2. The light-emitting substrate according to claim 1, characterized in that: The light transmittance of the optical regulation layer is greater than or equal to the light transmittance of the transparent reflective layer, and the light transmittance of the optical regulation layer is greater than or equal to 90%.

3. The light-emitting substrate according to claim 1, characterized in that: The extinction coefficient of the optical regulation layer is in the range of 0.001 m -1 ~0.005m -1 .

4. The light-emitting substrate according to claim 1, characterized in that: The material of the optical regulation layer is selected from any one of 4,4,4,-tris(carbazole-9-yl)triphenylamine, N,N'-diphenyl-N,N'-(1-naphthyl)-1,1'-biphenyl-4,4'-diamine, 4,4'-di(9-carbazole)biphenyl, silicon oxide, silicon nitride and silicon oxynitride.

5. The light-emitting substrate according to claim 1, characterized in that: The plurality of light emitting devices include: a first light emitting device configured to emit a first color light; The optical regulation layer comprises: a first regulation portion, the first regulation portion being arranged corresponding to the first light emitting device; Wherein, the thickness of the first regulating part ranges from 55nm to 65nm.

6. The light-emitting substrate according to claim 5, characterized in that: Also includes: A light extraction layer, located on a side of the transparent reflective layer away from the substrate; The light extraction layer comprises: a first light extraction portion, the first light extraction portion being arranged corresponding to the first light emitting device; Wherein, the thickness of the first light extraction portion is in the range of 85nm to 115nm.

7. The light-emitting substrate according to claim 5, characterized in that: The first light-emitting device further includes: a first hole transport layer; the first hole transport layer is located between the first electrode and the light-emitting layer of the first light-emitting device, or the first hole transport layer is located between the light-emitting layer and the second electrode of the first light-emitting device; Wherein, the thickness of the first hole transport layer is in the range of 20 nm to 30 nm.

8. The light-emitting substrate according to claim 5, characterized in that: The first light-emitting device further includes: a first electron transport layer; the first electron transport layer is located between the first electrode of the first light-emitting device and the light-emitting layer of the first light-emitting device, or the first electron transport layer is located between the light-emitting layer of the first light-emitting device and the second electrode of the first light-emitting device; Wherein, the thickness of the first electron transport layer is in the range of 30 nm to 70 nm.

9. The light-emitting substrate according to claim 5, characterized in that: The first light emitting device further comprises: a first hole transport layer and a first electron transport layer; The first electrode of the first light-emitting device, the first hole transport layer, the light-emitting layer of the first light-emitting device, the first electron transport layer and the second electrode of the first light-emitting device are arranged in a direction away from the substrate; or, the first electrode of the first light-emitting device, the first electron transport layer, the light-emitting layer of the first light-emitting device, the first hole transport layer and the second electrode of the first light-emitting device are arranged in a direction away from the substrate; The thickness of the first hole transport layer is in the range of 20 nm to 30 nm; the thickness of the first electron transport layer is in the range of 30 nm to 70 nm.

10. The light emitting substrate according to claim 1, characterized in that: The plurality of light emitting devices include: a second light emitting device configured to emit a second color light; The optical regulation layer comprises: a second regulation portion, wherein the second regulation portion is arranged corresponding to the second light emitting device; Wherein, the thickness of the second regulating part ranges from 95nm to 115nm.

11. The light emitting substrate according to claim 10, characterized in that: Also includes: A light extraction layer; the light extraction layer comprises: a second light extraction portion, the second light extraction portion being arranged corresponding to the second light emitting device; Wherein, the thickness of the second light extraction portion is in the range of 105nm to 145nm.

12. The light emitting substrate according to claim 10, characterized in that: The second light-emitting device further comprises: a second hole transport layer; the second hole transport layer is located between the first electrode of the second light-emitting device and the light-emitting layer of the second light-emitting device, or the second hole transport layer is located between the light-emitting layer of the second light-emitting device and the second electrode of the second light-emitting device; Wherein, the thickness of the second hole transport layer is in the range of 20 nm to 30 nm.

13. The light emitting substrate according to claim 10, characterized in that: The second light-emitting device further comprises: a second electron transport layer; the second electron transport layer is located between the first electrode of the second light-emitting device and the light-emitting layer of the second light-emitting device; or the second electron transport layer is located between the light-emitting layer of the second light-emitting device and the second electrode of the second light-emitting device; Wherein, the thickness of the second electron transport layer is in the range of 30 nm to 70 nm.

14. The light emitting substrate according to claim 10, characterized in that: The second light emitting device further comprises: a second hole transport layer and a second electron transport layer; The first electrode of the second light-emitting device, the second hole transport layer, the light-emitting layer of the second light-emitting device, the second electron transport layer and the second electrode of the second light-emitting device are arranged in a direction away from the substrate; or, the first electrode of the second light-emitting device, the second electron transport layer, the light-emitting layer of the second light-emitting device, the second hole transport layer and the second electrode of the second light-emitting device are arranged in a direction away from the substrate; The thickness of the second hole transport layer is in the range of 20 nm to 30 nm; the thickness of the second electron transport layer is in the range of 30 nm to 70 nm.

15. The light emitting substrate according to claim 1, characterized in that: The plurality of light emitting devices include: a third light emitting device configured to emit a third color light; The optical regulation layer comprises: a third regulation part, wherein the third regulation part is arranged corresponding to the third light emitting device; Wherein, the thickness of the third regulating part ranges from 5nm to 15nm.

16. The light emitting substrate according to claim 15, characterized in that: Also includes: A light extraction layer; the light extraction layer comprises: a third light extraction portion, the third light extraction portion being arranged corresponding to the third light emitting device; Wherein, the thickness of the third light extraction portion is in the range of 55nm to 85nm.

17. The light-emitting substrate according to claim 15 or 16, characterized in that: The third light-emitting device further includes: a third hole transport layer; the third hole transport layer is located between the first electrode of the third light-emitting device and the light-emitting layer of the third light-emitting device; or, the third hole transport layer is located between the light-emitting layer of the third light-emitting device and the second electrode of the third light-emitting device; Wherein, the thickness of the third hole transport layer ranges from 20 nm to 40 nm.

18. The light emitting substrate according to claim 15, characterized in that: The third light-emitting device further comprises: a third electron transport layer; the third electron transport layer is located between the first electrode of the third light-emitting device and the light-emitting layer of the third light-emitting device; or, the third electron transport layer is located between the light-emitting layer of the third light-emitting device and the second electrode of the third light-emitting device; Wherein, the thickness of the third electron transport layer ranges from 40 nm to 80 nm.

19. The light emitting substrate according to claim 15, characterized in that: The third light emitting device further includes: a third hole transport layer and a third electron transport layer; The first electrode of the third light-emitting device, the third hole transport layer, the light-emitting layer of the third light-emitting device, the third electron transport layer and the second electrode of the third light-emitting device are arranged in a direction away from the substrate; or, the first electrode of the third light-emitting device, the third electron transport layer, the light-emitting layer of the third light-emitting device, the third hole transport layer and the second electrode of the third light-emitting device are arranged in a direction away from the substrate; Wherein, the thickness of the third hole transport layer is in the range of 20 nm to 40 nm; the thickness of the third electron transport layer is in the range of 40 nm to 80 nm.

20. The light emitting substrate according to any one of claims 1 to 19, characterized in that: The light transmittance of the transparent reflective layer is in the range of greater than or equal to 60% and less than or equal to 90%; and / or, In the wavelength range of 400nm to 700nm, the light transmittance of the second electrode is greater than or equal to 85%.

21. The light-emitting substrate according to claim 20, characterized in that: The material of the transparent reflective layer and the material of the second electrode are independently selected from at least one of gold, silver, magnesium-silver alloy, molybdenum oxide, indium tin oxide, indium zinc oxide, indium tin zinc oxide, indium gallium oxide and aluminum-doped zinc oxide.

22. A light emitting device, characterized in that: include: The light-emitting substrate according to any one of claims 1 to 21; It also includes: a driving chip, which is used to drive the light-emitting substrate to emit light.

Images