Light-emitting diode display device and display apparatus

Abstract

Provided in one embodiment of the present disclosure are a light-emitting diode display device and a display apparatus. The light-emitting diode display device comprises a first electrode, a light-emitting functional layer and a second electrode which are sequentially stacked in a first direction, wherein the light-emitting functional layer comprises a first organic layer, a first light-emitting layer, a third organic layer, a charge generation layer, a fourth organic layer, a second light-emitting layer and a second organic layer which are sequentially stacked in the first direction; and the thickness range of a first portion of the first organic layer corresponding to a blue sub-pixel is 120-180 nm, the thickness range of a second portion thereof corresponding to a green sub-pixel is 140-180 nm, and the thickness range of a third portion thereof corresponding to a red sub-pixel is 160-240 nm. Increasing the thickness of the first organic layer can reduce light loss caused by the plasma polarization effect, thereby achieving a better balanced state between electron transport and hole transport, and thus improving the display efficiency and service life of the light-emitting diode display device.

Description

Light emitting diode display device and display apparatus TECHNICAL FIELD

[0001] Embodiments of the present disclosure relate to a light emitting diode display device and a display apparatus. BACKGROUND

[0002] With the continuous development of display technology, customers have higher and higher requirements for the resolution of display products and lower and lower requirements for the numerical value of power consumption. Therefore, it is necessary to develop display devices with high efficiency, low voltage and long service life. In recent years, organic light emitting diode displays (OLED) have received more and more attention as a new type of flat panel display device. Organic light emitting diode displays have become the research focus and the direction of technological development of major manufacturers at present because they have the advantages of active light emission, wide color gamut, high contrast, thin design, high luminous brightness, high resolution, wide viewing angle, fast response speed, low energy consumption and flexibility, and have become the mainstream display products in the current market.

[0003] At present, organic light emitting diode display devices (OLED) have been widely applied to various electronic products, such as smart bracelets, smart watches, smart phones, tablet computers and other electronic products, and notebook computers, desktop computers, televisions and other electronic products. Therefore, the market demand for organic light emitting diode display devices is also increasing.

[0004] SUMMARY

[0005] At least one embodiment of the present disclosure provides a light emitting diode display device and a display apparatus. The light emitting diode display device has a first organic layer with a first part corresponding to a blue sub-pixel having a thickness range of 120nm-180nm, a second part corresponding to a green sub-pixel having a thickness range of 140nm-180nm, and a third part corresponding to a red sub-pixel having a thickness range of 160nm-240nm. In this way, the electron transport and hole transport can reach an optimal balance, so that the display efficiency and service life of the light emitting diode display device can be improved.

[0006] At least one embodiment of the present disclosure provides a light emitting diode display device. The light emitting diode display device includes a first electrode, a light emitting functional layer and a second electrode which are sequentially stacked in a first direction. The light emitting functional layer includes a first organic layer, a first light emitting layer, a third organic layer, a charge generation layer, a fourth organic layer, a second light emitting layer and a second organic layer which are sequentially stacked in the first direction. The first organic layer has a first part corresponding to a blue sub-pixel with a thickness range of 120nm-180nm, a second part corresponding to a green sub-pixel with a thickness range of 140nm-180nm, and a third part corresponding to a red sub-pixel with a thickness range of 160nm-240nm.

[0007] For example, in the light emitting diode display device provided by at least one embodiment of the present disclosure, the first organic layer comprises a first hole transport layer, the fourth organic layer comprises a second hole transport layer, the charge generation layer comprises an electron charge generation layer and a hole charge generation layer arranged in a stack, the electron charge generation layer is closer to the first organic layer than the hole charge generation layer, the second hole transport layer and the hole charge generation layer are arranged adjacently, and the thickness of the first hole transport layer is greater than the thickness of the second hole transport layer.

[0008] For example, in the light emitting diode display device provided by at least one embodiment of the present disclosure, the third organic layer comprises a first electron transport layer, the second organic layer comprises a second electron transport layer, the first electron transport layer and the electron charge generation layer are arranged adjacently, and the thickness of the second electron transport layer is greater than the thickness of the first electron transport layer.

[0009] For example, in the light emitting diode display device provided by at least one embodiment of the present disclosure, the thickness of the first organic layer is greater than the thickness of the fourth organic layer, and the thickness of the second organic layer is greater than the thickness of the third organic layer.

[0010] For example, in the light emitting diode display device provided by at least one embodiment of the present disclosure, the ratio of the thickness of the fourth organic layer to the thickness of the first organic layer ranges from 20% to 60%, and the ratio of the thickness of the third organic layer to the thickness of the second organic layer ranges from 50% to 90%.

[0011] For example, in the light emitting diode display device provided by at least one embodiment of the present disclosure, the ratio of the thickness of the fourth organic layer to the thickness of the first organic layer ranges from 30% to 50%, and the ratio of the thickness of the third organic layer to the thickness of the second organic layer ranges from 60% to 80%.

[0012] For example, in the light emitting diode display device provided by at least one embodiment of the present disclosure, the first organic layer further comprises a first electron blocking layer arranged on the side of the first hole transport layer away from the first electrode, the ratio of the thickness of the first electron blocking layer to the thickness of the first hole transport layer ranges from 3% to 30% for the part corresponding to the blue sub-pixel, the ratio of the thickness of the first electron blocking layer to the thickness of the first hole transport layer ranges from 10% to 50% for the part corresponding to the green sub-pixel, and the ratio of the thickness of the first electron blocking layer to the thickness of the first hole transport layer ranges from 30% to 75% for the part corresponding to the red sub-pixel.

[0013] For example, in the light emitting diode display device provided by at least one embodiment of the present disclosure, the first organic layer further comprises a hole injection layer disposed on a side of the first hole transport layer close to the first electrode, and a material of the hole injection layer comprises a hole transport material and a strong electron-withdrawing p-type dopant doped in the hole transport material.

[0014] For example, in the light emitting diode display device provided by at least one embodiment of the present disclosure, a material of the hole injection layer comprises at least one of hexacyanohexaazatriphenylene, 2,3,5,6-tetrafluoro-7,7,8,8-tetracyano-p-quinodimethane (F4TCNQ), and 1,2,3-tris[(cyano)(4-cyano-2,3,5,6-tetrafluorophenyl)methylene]cyclopropane.

[0015] For example, in the light emitting diode display device provided by at least one embodiment of the present disclosure, materials of the first hole transport layer, the second hole transport layer, and the hole charge generation layer are all hole transport materials.

[0016] For example, in the light emitting diode display device provided by at least one embodiment of the present disclosure, the hole transport material comprises at least one of arylamine-based materials, dimethylfluorene, and carbazole-based materials.

[0017] For example, in the light emitting diode display device provided by at least one embodiment of the present disclosure, the hole transport material comprises at least one of 4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (NPB), N,N'-bis(3-methylphenyl)-N,N'-diphenyl-[1,1'-biphenyl]-4,4'-diamine (TPD), 4-phenyl-4'-(9-phenylfluorene-9-yl)triphenylamine (BAFLP), 4,4'-bis[N-(9,9-dimethylfluorene-2-yl)-N-phenylamino]biphenyl (DFLDPBi), 4,4'-di(9-carbazolyl) biphenyl (CBP), and 9-phenyl-3-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazole (PCzPA).

[0018] For example, in the light emitting diode display device provided by at least one embodiment of the present disclosure, the first light emitting layer and the second light emitting layer each comprise red light emitting materials, green light emitting materials, and blue light emitting materials; the blue light emitting materials comprise at least one of pyrene derivatives, anthracene derivatives, fluorene derivatives, perylene derivatives, styrylamine derivatives, and metal complexes; the green light emitting materials comprise at least one of coumarin dyes, quinacridone copper derivatives, polycyclic aromatic hydrocarbons, anthracene derivatives, carbazole derivatives, and metal complexes; and the red light emitting materials comprise at least one of 4-(dicyanomethylene)-2-methyl-6-(4-dimethylaminostyryl)-4H-pyran (DCM) and metal complexes.

[0019] For example, in the light emitting diode display device provided by at least one embodiment of the present disclosure, the blue light emitting material includes at least one of N1,N6-di([1,1'-biphenyl]-2-yl)-N1,N6-di([1,1'-biphenyl]-4-yl)pyrene-1,6-diamine, 9,10-di-(2-naphthyl)anthracene (ADN), 2-methyl-9,10-di-2-naphthylanthracene (MADN), 2,5,8,11-tetra-tert-butylperylene (TBPe), 4,4'-bis[4-(diphenylamino)styryl]biphenyl (BDAV Bi), 4,4'-bis[4-(dipara-tolylamino)styryl]biphenyl (DPAVBi), and bis(4,6-difluorophenylpyridine-C2,N)picolatoiridium (FIrpic).

[0020] For example, in the light emitting diode display device provided by at least one embodiment of the present disclosure, the green light emitting material includes at least one of Coumarin 6 (C-6), Coumarin 545T (C-525T), quinacridone copper (QA), N,N'-dimethylquinacridone (DMQA), 5,12-diphenyl naphthacene (DPT), N10,N10'-diphenyl-N10,N10'-dibenzoyl-9,9'-diphenylanthracene-10,10'-diamine (abbreviation: BA-NPB), tris(8-hydroxyquinolato)aluminum (III) (abbreviation: Alq3), tris(2-phenylpyridine)iridium (Ir(ppy)3), and bis(2-phenylpyridine)iridium acetylacetonate (Ir(ppy)2(acac)).

[0021] For example, in the light emitting diode display device provided by at least one embodiment of the present disclosure, the red light emitting material includes at least one of 4-(dicyanomethylene)-2-methyl-6-(4-dimethylaminostyryl)-4H-pyran (DCM), 4-(dicyanomethylene)-2-tert-butyl-6-(1,1,7,7-tetramethyljuglavin-9-enyl)-4H-pyran (DCJTB), bis(1-phenylisoquinoline)(acetylacetonate)iridium (III) (Ir(piq)2(acac)), octaethylporphyrin platinum (abbreviation: PtOEP), and bis(2-(2'-benzothienyl)pyridine-N,C3')(acetylacetonate)iridium.

[0022] For example, in the light emitting diode display device provided by at least one of the embodiments of the present disclosure, the third organic layer includes a first hole blocking layer disposed on a side of the first electron transport layer close to the first electrode, the second organic layer includes a second hole blocking layer disposed on a side of the second electron transport layer close to the first electrode, and the materials of the first electron transport layer, the first hole blocking layer, the second electron transport layer, the second hole blocking layer and the electron charge generation layer are all selected from at least one of a benzimidazole derivative, an imidazopyridine derivative, a benzimidazophenanthroline derivative, a pyrimidine derivative, a triazine derivative, a quinoline derivative, an isoquinoline derivative and a phenanthroline derivative.

[0023] For example, in the light emitting diode display device provided by at least one of the embodiments of the present disclosure, the materials of the first electron transport layer, the first hole blocking layer, the second electron transport layer, the second hole blocking layer and the electron charge generation layer are all selected from at least one of 2-(4-biphenyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (PBD), 1,3-bis[5-(p-tert-butylphenyl)-1,3,4-oxadiazol-2-yl]benzene (OXD-7), 3-(4-tert-butylphenyl)-4-phenyl-5-(4-biphenyl)-1,2,4-triazole (TAZ), 3-(4-tert-butylphenyl)-4-(4-ethylphenyl)-5-(4-biphenyl)-1,2,4-triazole (p-EtTAZ), 4,7-diphenyl-1,10-phenanthroline (BPhen), 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP), 4,4'-bis(5-methylbenzoxazol-2-yl)stilbene (BzOs).

[0024] For example, the light emitting diode display device provided by at least one of the embodiments of the present disclosure further includes an electron injection layer disposed on a side of the second organic layer close to the second electrode, and the material of the electron injection layer includes an alkali metal.

[0025] For example, in the light emitting diode display device provided by at least one of the embodiments of the present disclosure, the fourth organic layer further includes a second electron blocking layer disposed on a side of the second hole transport layer close to the second light emitting layer.

[0026] The display device provided by at least one of the embodiments of the present disclosure includes the light emitting diode display device described in any one of the above. BRIEF DESCRIPTION OF DRAWINGS

[0027] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings of the embodiments will be briefly introduced below. Obviously, the drawings described in the following are only related to some of the embodiments of the present disclosure, but not limit the present disclosure.

[0028] FIG. 1 is a schematic diagram of a cross-sectional structure of a light emitting diode display device corresponding to a blue light emitting element;

[0029] FIG. 2 is a schematic diagram of a cross-sectional structure of a light emitting diode display device according to an embodiment of the present disclosure; and

[0030] FIG. 3 is a schematic diagram of a display device according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0031] In order to make the objects, technical solutions and advantages of the embodiments of the present disclosure clearer, the technical solutions of the embodiments of the present disclosure will be described clearly and completely below with reference to the drawings of the embodiments of the present disclosure. Obviously, the described embodiments are only some of the embodiments of the present disclosure, but not all the embodiments of the present disclosure. Based on the described embodiments of the present disclosure, all other embodiments obtained by those of ordinary skill in the art without creative effort belong to the scope of protection of the present disclosure.

[0032] Unless otherwise defined, technical terms or scientific terms used in the present disclosure shall have the ordinary meaning understood by those skilled in the art to which the present disclosure pertains. The terms "first", "second", and similar terms used in the present disclosure do not denote any order, quantity, or importance, but are used to distinguish different components. The terms "include", "contain", and similar terms mean that the elements or objects before the terms encompass the elements or objects listed after the terms and their equivalents, and do not exclude other elements or objects. The terms "connect" or "connected" and similar terms are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. The terms "upper", "lower", "left", "right", and the like only represent relative positional relationships, and when the absolute positions of the described objects are changed, the relative positional relationships can also be changed accordingly.

[0033] Unless otherwise defined, all features which are described in the embodiments of the present application including "parallel", "perpendicular", "same" and the like are intended to encompass strict "parallel", "perpendicular", "same" and the like as well as "approximately parallel", "approximately perpendicular", "approximately same" and the like with a certain error. For example, the "approximately" described above can mean that the difference of the compared objects is within 10% or 5% of the average value of the compared objects. In the following description of the embodiments of the present application, unless the number of a component or element is specifically indicated, it means that the component or element can be one or more, or can be understood as at least one. "At least one" means one or more, and "more" means at least two. In the embodiments of the present application, "same layer" refers to the relationship between multiple film layers formed by the same material after the same step (for example, one patterning process). Here, "same layer" does not always mean that the thickness of the multiple film layers is the same or the height of the multiple film layers in the cross-sectional view is the same.

[0034] Organic light emitting display devices (OLEDs) have received more and more attention as a new type of flat panel display device. Due to its characteristics of active light emission, high luminance, high resolution, wide viewing angle, fast response speed, low power consumption, and flexibility, it has become a mainstream display product in the market. With the continuous development of display products, consumers have increasingly high requirements for the resolution of display products and increasingly low requirements for power consumption. Therefore, it is necessary to develop a display device with high efficiency, low voltage, and long service life.

[0035] The stacked device formed by the organic light emitting diode is to stack multiple light emitting units of the same color through the charge generation layer, so that the light emitting efficiency of the whole stacked device is improved to 1.5-2 times of the light emitting efficiency of the single-layer organic light emitting diode display device formed by a single light emitting unit. Under the condition of the same display brightness, the service life of the stacked device can be improved to 3 times or more of the service life of the single-layer light emitting device. The stacked device formed by the organic light emitting diode is widely used in the field of display panels, vehicle-mounted products, lighting, and other light emitting devices requiring long service life. Due to its high light emitting efficiency and long service life, the stacked device formed by the organic light emitting diode can be widely used in more special scenarios, and therefore, there are increasingly high requirements for the stability and service life of the stacked device formed by the organic light emitting diode.

[0036] In the organic light emitting diode display panel, the material of the anode mostly includes metal oxide material such as indium tin oxide and metal material such as silver, the roughness of the metal oxide film layer formed is different, and the cleanliness of the impurity removal in the preparation process is different, which will affect the stability of the organic light emitting diode display device formed by evaporation when displaying. The higher the roughness of the metal oxide film layer or the more impurities remaining, the more likely to cause the leakage current or electrostatic breakdown of the light emitting diode display device, thereby causing the display failure of the light emitting diode display device. In addition, since the anode also includes a silver metal layer, when the light emitting layer is close to the anode, a large amount of light loss will be caused due to the plasma polarization effect, so that the part of light cannot be effectively conducted to the outside of the light emitting diode display device, thereby causing the display efficiency of the light emitting diode display device to be low. Therefore, a certain distance needs to be maintained between the light emitting layer and the anode in the light emitting diode display device.

[0037] In addition, since the anode and the cathode in the organic light emitting diode formed stack device both include metal material, which has high injection and transmission capacity for electrons and holes, and the charge generation layer located in the middle position of the stack device is usually formed by organic material with doping system, which has lower injection and transmission characteristics than metal material. Therefore, the hole transport layer close to the anode needs to be thicker than the hole transport layer close to the hole charge generation layer, and similarly, the electron transport layer close to the cathode needs to be thicker than the electron transport layer close to the electron charge generation layer, so as to maintain the balance and consistency of the injection and transmission of holes and electrons of the upper and lower two light emitting units, so as to make the display efficiency of the organic light emitting diode formed stack device highest.

[0038] For example, FIG. 1 is a schematic diagram of a cross-sectional structure of a light-emitting diode stack display device corresponding to a blue light-emitting element. As shown in FIG. 1, the organic light-emitting diode stack device 100 includes, in order, an anode reflective layer 101, an anode 102, a hole injection layer 103, a first hole transport layer 104, a first electron blocking layer 105, a first light-emitting layer 106, a first hole blocking layer 107, a first electron transport layer 108, an electron charge generation layer 109, a hole charge generation layer 110, a second hole transport layer 111, a second electron blocking layer 112, a second light-emitting layer 113, a second hole blocking layer 114, a second electron transport layer 115, an electron injection layer 116, and a cathode 117. The thickness of the anode reflective layer 101 is 100 nm, the thickness of the anode 102 is 8 nm, the thickness of the hole injection layer 103 is 10 nm, the thickness of the first hole transport layer 104 is 20 nm, the thickness of the first electron blocking layer 105 is 10 nm, the thickness of the first light-emitting layer 106 is 15 nm, the thickness of the first hole blocking layer 107 is 5 nm, the thickness of the first electron transport layer 108 is 20 nm, the thickness of the N-type charge generation layer 109 is 18 nm, the thickness of the P-type charge generation layer 110 is 10 nm, the thickness of the second hole transport layer 111 is 30 nm, the thickness of the second electron blocking layer 112 is 10 nm, the thickness of the second light-emitting layer 113 is 15 nm, the thickness of the second hole blocking layer 114 is 5 nm, the thickness of the second electron transport layer 115 is 35 nm, the thickness of the electron injection layer 116 is 1 nm, and the thickness of the cathode 117 is 15 nm. The entire stack of the hole injection layer 103, the first hole transport layer 104, and the first electron blocking layer 105 is defined as a first organic layer 120, and the thickness of the first organic layer 120 is about 50 nm. However, the inventors of the present disclosure have noted that when the thickness of the first organic layer 120 is about 50 nm, the light extraction efficiency of the top-emitting organic light-emitting diode stack device is only about 20%, which is mainly affected by the energy loss of the optical waveguide and surface plasmonic polariton (SPP) in the organic light-emitting diode stack device. The surface plasmon is mainly concentrated at the interface between the metal layer and the organic layer, which is strongly related to the distance between the light-emitting layer and the metal electrode. For example, the light intensity loss caused by the plasmon at the interface between the metal layer and the organic layer can be as high as 40%.In the cross-sectional structure shown in FIG. 1, since the distance between the first light-emitting layer 106 and the anode 102 is not more than 50 nm, the light loss caused by plasmons at the interface between the metal layer and the organic layer is relatively strong, and the light extraction efficiency can be effectively improved by increasing the distance between the first light-emitting layer 106 and the anode 102. However, since the light extraction intensity of the first light-emitting layer 106 at different positions in the entire microcavity is also affected by the light-emitting wavelength, when the thickness of the first organic layer 120 increases to a certain value, the stacked device of the organic light-emitting diode can obtain higher light-emitting efficiency. For a blue light-emitting device, when the thickness of the first organic layer is increased to about 150 nm, the highest light-emitting efficiency can be obtained. In addition, in the organic light-emitting diode display panel, since the roughness of the metal oxide film layer included in the anode 102 is different and the cleanliness of the impurity removal in the preparation process is different, the leakage current or electrostatic breakdown of the stacked device of the organic light-emitting diode is easy to cause, thereby causing the display panel formed finally to have display defects. Therefore, increasing the thickness of the first organic layer 120 can also reduce the risk of electrostatic breakdown or leakage current of the stacked device of the organic light-emitting diode.

[0039] For example, the inventors of the present disclosure noticed that, under the same other conditions, when the thickness of the first organic layer 120 in the blue light-emitting element is 50 nm, the light-emitting efficiency of the blue light-emitting element is 100%, when the thickness of the first organic layer 120 in the blue light-emitting element is 150 nm, the light-emitting efficiency of the blue light-emitting element is 114%; when the thickness of the first organic layer in the green light-emitting element is 55 nm, the light-emitting efficiency of the green light-emitting element is 100%, when the thickness of the first organic layer in the green light-emitting element is 170 nm, the light-emitting efficiency of the green light-emitting element is 103%; when the thickness of the first organic layer in the red light-emitting element is 60 nm, the light-emitting efficiency of the red light-emitting element is 100%, when the thickness of the first organic layer in the red light-emitting element is 190 nm, the light-emitting efficiency of the red light-emitting element is 111%. The above data shows that for red, green and blue light-emitting elements, increasing the thickness of the first organic layer can reduce the light loss caused by plasmonic polarization, thereby improving the light-emitting efficiency of the display device.

[0040] The inventors of the present disclosure also noticed that an organic light-emitting diode stacked device can be designed by increasing the distance between the anode and the first light-emitting layer, and by limiting the relative thickness of the distance between the electron transport layer and the hole transport layer arranged above and below the two light-emitting layers, the influence of the roughness and impurities of the display substrate on the stacked device formed by the organic light-emitting diode is reduced, the plasmonic polarization loss is reduced to increase the light extraction efficiency of the display device, and the balance of electron and hole transmission is adjusted to obtain an organic light-emitting diode stacked device with optimal light-emitting efficiency and longest service life.

[0041] The light-emitting diode display device provided by at least one embodiment of the present disclosure includes: a first electrode, a light-emitting functional layer, and a second electrode which are sequentially stacked in a first direction, the light-emitting functional layer includes a first organic layer, a first light-emitting layer, a third organic layer, a charge generation layer, a fourth organic layer, a second light-emitting layer, and a second organic layer which are sequentially stacked in the first direction, a thickness range of a first part of the first organic layer corresponding to a blue sub-pixel is 120 nm to 180 nm, a thickness range of a second part of the first organic layer corresponding to a green sub-pixel is 140 nm to 180 nm, and a thickness range of a third part of the first organic layer corresponding to a red sub-pixel is 160 nm to 240 nm, and the light-emitting diode display device can reduce light loss caused by plasmonic polarization effect and improve light-emitting efficiency of the display device by limiting the thickness range of the first part of the first organic layer corresponding to the blue sub-pixel to 120 nm to 180 nm, limiting the thickness range of the second part of the first organic layer corresponding to the green sub-pixel to 140 nm to 180 nm, and limiting the thickness range of the third part of the first organic layer corresponding to the red sub-pixel to 160 nm to 240 nm.

[0042] For example, FIG. 2 is a schematic diagram of a cross-sectional structure of a light-emitting diode display device provided by at least one embodiment of the present disclosure, as shown in FIG. 2, the light-emitting diode display device 200 includes: a first electrode 201, a light-emitting functional layer 202, and a second electrode 203 which are sequentially stacked in a first direction X, the light-emitting functional layer 202 includes a first organic layer 2021, a first light-emitting layer 2022, a third organic layer 2023, a charge generation layer 2024, a fourth organic layer 2025, a second light-emitting layer 2026, and a second organic layer 2027 which are sequentially stacked in the first direction X, a thickness range of a first part of the first organic layer 2021 corresponding to a blue sub-pixel is 120 nm to 180 nm, a thickness range of a second part of the first organic layer 2021 corresponding to a green sub-pixel is 140 nm to 180 nm, and a thickness range of a third part of the first organic layer 2021 corresponding to a red sub-pixel is 160 nm to 240 nm, and the light-emitting diode display device 200 can reduce plasmonic polarization loss, increase light extraction efficiency of the light-emitting diode display device, and obtain an organic light-emitting diode stack device with optimal light-emitting efficiency and longest service life by adjusting a balance of electron and hole transmission by setting the thickness of the part of the first organic layer 2021 corresponding to the sub-pixel of different colors to the above range.

[0043] For example, in one example, the first portion corresponding to the blue sub-pixel of the first organic layer 2021 has a thickness of 120 nm, 130 nm, 140 nm, 150 nm, 160 nm, 170 nm, or 180 nm. The second portion corresponding to the green sub-pixel has a thickness of 140 nm, 150 nm, 160 nm, 170 nm, or 180 nm. The third portion corresponding to the red sub-pixel has a thickness of 160 nm, 170 nm, 180 nm, 190 nm, 200 nm, 210 nm, 220 nm, 230 nm, or 240 nm.

[0044] It should be noted that although in FIG. 2, the first organic layer 2021 is a flat structure of a whole layer, in actual products, the surface of the first portion of the first organic layer 2021 corresponding to the blue sub-pixel, the surface of the second portion corresponding to the green sub-pixel, and the surface of the third portion corresponding to the red sub-pixel are not in the same plane.

[0045] For example, as shown in FIG. 2, the first organic layer 2021 includes a first hole transport layer 2021a, the fourth organic layer 2025 includes a second hole transport layer 2025a, the charge generation layer 2024 includes an electron charge generation layer 2024a and a hole charge generation layer 2024b stacked, the electron charge generation layer 2024a is closer to the first organic layer 2021 than the hole charge generation layer 2024b, the second hole transport layer 2025a and the hole charge generation layer 2024b are arranged adjacent to each other, and the thickness of the first hole transport layer 2021a is greater than the thickness of the second hole transport layer 2025a. For example, the first electrode 201 is the anode of the light-emitting diode display device 200, and the second electrode 203 is the cathode of the light-emitting diode display device 200, that is, the thickness of the first hole transport layer 2021a closer to the anode side is greater than the thickness of the second hole transport layer 2025a farther away from the anode 201, which can improve the efficiency of hole transport. Moreover, the second hole transport layer 2025a and the hole charge generation layer 2024b are arranged adjacent to each other, so that the holes formed in the hole charge generation layer 2024b can be transported through the second hole transport layer 2025a, thereby improving the efficiency of hole transport.

[0046] For example, as shown in FIG. 2, the third organic layer 2023 includes a first electron transport layer 2023a, the second organic layer 2027 includes a second electron transport layer 2027a, the first electron transport layer 2023a and the electron charge generation layer 2024a are arranged adjacently, and the thickness of the second electron transport layer 2027a is greater than the thickness of the first electron transport layer 2023a. For example, the first electrode 201 is the anode of the light-emitting diode display device 200, and the second electrode 203 is the cathode of the light-emitting diode display device 200, i.e., the thickness of the second electron transport layer 2027a closer to the cathode 203 is greater than the thickness of the first electron transport layer 2023a farther from the cathode 203, so that the efficiency of electron transport can be improved. Moreover, the first electron transport layer 2023a and the electron charge generation layer 2024a are arranged adjacently, so that the electrons formed in the electron charge generation layer 2024a can be transported through the first electron transport layer 2023a, so that the efficiency of electron transport can be improved.

[0047] For example, in one example, the thickness of the first organic layer 2021 is greater than the thickness of the fourth organic layer 2025, and the thickness of the second organic layer 2027 is greater than the thickness of the third organic layer 2023. That is, the first organic layer 2021 and the fourth organic layer 2025 respectively include a first hole transport layer 2021a and a second hole transport layer 2025a which play a transport role for holes, and the overall thickness of the first organic layer 2021 closer to the first electrode 201 is greater than the overall thickness of the fourth organic layer 2025, so that the transport of holes can be better achieved.

[0048] For example, in a light emitting diode display device having a double-layered structure, both the first electrode 201 and the second electrode 203 include a metal material. The second electrode 203 has a high injection and transport capability for electrons, the first electrode 201 has a high injection and transport capability for holes, and the material of the charge generation layer 2024 located in the middle of the double-layered structure is a doped organic material. The hole charge generation layer 2024b formed of the doped organic material has a somewhat lower injection and transport capability for holes with respect to the first electrode 201 of the metal material, and the electron charge generation layer 2024a formed of the doped organic material has a somewhat lower injection and transport capability for electrons with respect to the second electrode 203 of the metal material. Therefore, the first hole transport layer 2021a close to the first electrode (anode) 201 needs to be thicker than the second hole transport layer 2025a close to the hole charge generation layer 2024b, and the second electron transport layer 2027a close to the second electrode (cathode) 203 needs to be thicker than the first electron transport layer 2023a close to the electron charge generation layer 2024a, so as to maintain a balance and consistency of the injection and transport of holes and electrons of the upper and lower light emitting units, and to obtain the optimal performance of the light emitting diode display device. Furthermore, designing the thickness of the first organic layer 2021 to be greater than the thickness of the fourth organic layer 2025 and designing the thickness of the second organic layer 2027 to be greater than the thickness of the third organic layer 2023 can obtain the optimal exciton balance to achieve the highest light emitting efficiency and the longest service life.

[0049] For example, considering the electron charge generation layer 2024a and the hole charge generation layer 2024b formed of organic materials, the hole mobility is relatively large, and the electron mobility is relatively small. In one example, the thickness of the fourth organic layer 2025 is designed to have a ratio to the thickness of the first organic layer 2021 in a range of 20% to 60%, and the thickness of the third organic layer 2023 is designed to have a ratio to the thickness of the second organic layer 2027 in a range of 50% to 90%, so as to better balance the injection and transport efficiency of electrons and holes.

[0050] For example, in another example, the thickness of the fourth organic layer 2025 has a ratio to the thickness of the first organic layer 2021 in a range of 30% to 50%, and the thickness of the third organic layer 2023 has a ratio to the thickness of the second organic layer 2027 in a range of 60% to 80%. For example, the thickness of the fourth organic layer 2025 has a ratio to the thickness of the first organic layer 2021 of 30%, 35%, 40%, 45%, and 50%, and the thickness of the third organic layer 2023 has a ratio to the thickness of the second organic layer 2027 of 60%, 65%, 70%, 75%, and 80%, so as to balance the injection and transport efficiency of electrons and holes.

[0051] For example, since the overall thickness of the first organic layer 2021 is the largest in the entire light-emitting diode display device, the first organic layer 2021 needs to have a high hole transport rate. Generally, the transport efficiency of holes in the hole transport layer is greater than the transport efficiency of holes in the electron blocking layer, and thus, in the case of ensuring the overall thickness of the first organic layer, the thickness of the electron blocking layer included therein needs to be limited to a low proportion to maintain a high hole transport rate of the entire first organic layer, so as to reduce the voltage of the entire light-emitting diode display device and make the exciton distribution of the entire light-emitting diode display device more balanced.

[0052] For example, in one example, the first organic layer 2021 further includes a first electron blocking layer 2021b disposed on the side of the first hole transport layer 2021a away from the first electrode 201, and the thickness of the first electron blocking layer 2021b is less than the thickness of the first hole transport layer 2021a. The ratio of the thickness of the first electron blocking layer 2021b to the thickness of the first hole transport layer 2021a in the portion corresponding to the blue sub-pixel ranges from 3% to 30%; the ratio of the thickness of the first electron blocking layer 2021b to the thickness of the first hole transport layer 2021a in the portion corresponding to the green sub-pixel ranges from 10% to 50%; and the ratio of the thickness of the first electron blocking layer 2021b to the thickness of the first hole transport layer 2021a in the portion corresponding to the red sub-pixel ranges from 30% to 75%. The light-emitting diode display device 200 can reduce plasmonic polarization loss by setting the thickness of the first electron blocking layer 2021b to the thickness of the first hole transport layer 2021a in the portion corresponding to the sub-pixel of different colors within the above ratio range, so as to increase the light extraction efficiency of the light-emitting diode display device while regulating the transport balance of electrons and holes to obtain a stacked device of an organic light-emitting diode with optimal light-emitting efficiency and longest service life.

[0053] For example, in Table 1 below, the light-emitting efficiency of the light-emitting diode display device provided by the embodiment of the present disclosure and having different thicknesses of the first organic layer corresponding to sub-pixels of different colors and the light-emitting efficiency of a conventional light-emitting diode display device are studied by using optical simulation experiments.

[0054] Table 1: Comparison of the light-emitting efficiency of the light-emitting diode display device provided by the embodiment of the present disclosure and the light-emitting efficiency of a conventional light-emitting diode display device.

[0055] For the stacked light-emitting diode display device, the light-emitting diode display device can be made into a single-color light-emitting diode display device for testing, or a light-emitting element of one color among the red light-emitting element, the green light-emitting element and the blue light-emitting element of the light-emitting diode display device can be lighted up to test the light-emitting efficiency of the light-emitting diode display device. As can be seen from Table 1 above, in the conventional organic light-emitting diode display device, the thickness of the first organic layer corresponding to the blue light-emitting element is 50 nm, and the light-emitting efficiency of the light-emitting diode display device corresponding thereto is 100%, while in the light-emitting diode display device provided by the embodiments of the present disclosure, the thickness of the first organic layer corresponding to the blue light-emitting element is 150 nm, and the light-emitting efficiency of the light-emitting diode display device corresponding thereto is 114%. In the conventional organic light-emitting diode display device, the thickness of the first organic layer corresponding to the green light-emitting element is 55 nm, and the light-emitting efficiency of the light-emitting diode display device corresponding thereto is 100%, while in the light-emitting diode display device provided by the embodiments of the present disclosure, the thickness of the first organic layer corresponding to the green light-emitting element is 170 nm, and the light-emitting efficiency of the light-emitting diode display device corresponding thereto is 103%. In the conventional organic light-emitting diode display device, the thickness of the first organic layer corresponding to the red light-emitting element is 60 nm, and the light-emitting efficiency of the light-emitting diode display device corresponding thereto is 100%, while in the light-emitting diode display device provided by the embodiments of the present disclosure, the thickness of the first organic layer corresponding to the red light-emitting element is 190 nm, and the light-emitting efficiency of the light-emitting diode display device corresponding thereto is 111%. That is, in the embodiments of the present disclosure, by thickening the thickness of the first organic layer corresponding to the sub-pixels of different colors, the light-emitting efficiency of the light-emitting diode display device provided by the embodiments of the present disclosure is higher than that of the conventional light-emitting diode display device.

[0056] For example, in Table 2 below, the voltage, the light-emitting efficiency, and the service life of the light-emitting diode display device provided by the embodiments of the present disclosure and the voltage, the light-emitting efficiency, and the service life of the conventional light-emitting diode display device are studied by optical simulation experiments.

[0057] Table 2: Comparison of the voltage, the light-emitting efficiency, and the service life of the light-emitting diode display device provided by the embodiments of the present disclosure and the voltage, the light-emitting efficiency, and the service life of the conventional light-emitting diode display device.

[0058] For the stacked light-emitting diode display device, the light-emitting diode display device can be made into a single-color light-emitting diode display device for testing, or a light-emitting element of one color among the red light-emitting element, the green light-emitting element and the blue light-emitting element of the light-emitting diode display device can be lighted up to test the efficiency of the light-emitting diode display device. As can be seen from Table 2 above, in the conventional organic light-emitting diode display device, the thickness of the first organic layer corresponding to the blue light-emitting element is 48 nm, the thickness of the second organic layer is 35 nm, the thickness of the third organic layer is 35 nm, and the thickness of the fourth organic layer is 33 nm, the voltage of the corresponding light-emitting diode display device is 100%, the luminous efficiency is 100%, and the service life is 100%, and in the light-emitting diode display device provided by the embodiment of the present disclosure, the thickness of the first organic layer corresponding to the blue light-emitting element is 148 nm, the thickness of the second organic layer is 40 nm, the thickness of the third organic layer is 25 nm, and the thickness of the fourth organic layer is 55 nm, the voltage of the corresponding light-emitting diode display device is 103%, the luminous efficiency is 111%, and the service life is 147%. In the conventional organic light-emitting diode display device, the thickness of the first organic layer corresponding to the green light-emitting element is 50 nm, the thickness of the second organic layer is 35 nm, the thickness of the third organic layer is 35 nm, and the thickness of the fourth organic layer is 35 nm, the voltage of the corresponding light-emitting diode display device is 100%, the luminous efficiency is 100%, and the service life is 100%, and in the light-emitting diode display device provided by the embodiment of the present disclosure, the thickness of the first organic layer corresponding to the green light-emitting element is 168 nm, the thickness of the second organic layer is 40 nm, the thickness of the third organic layer is 25 nm, and the thickness of the fourth organic layer is 65 nm, the voltage of the corresponding light-emitting diode display device is 104%, the luminous efficiency is 105%, and the service life is 135%. In the conventional organic light-emitting diode display device, the thickness of the first organic layer corresponding to the red light-emitting element is 52 nm, the thickness of the second organic layer is 35 nm, the thickness of the third organic layer is 35 nm, and the thickness of the fourth organic layer is 37 nm, the voltage of the corresponding light-emitting diode display device is 100%, the luminous efficiency is 100%, and the service life is 100%, and in the light-emitting diode display device provided by the embodiment of the present disclosure, the thickness of the first organic layer corresponding to the red light-emitting element is 188 nm, the thickness of the second organic layer is 40 nm, the thickness of the third organic layer is 25 nm, and the thickness of the fourth organic layer is 75 nm, the voltage of the corresponding light-emitting diode display device is 104%, the luminous efficiency is 109%, and the service life is 122%.That is, in the embodiments of the present disclosure, by thickening the first organic layer corresponding to the sub-pixels of different colors, and adaptively adjusting the thicknesses of the second, third and fourth organic layers, the light-emitting diode display device provided by the embodiments of the present disclosure can have a higher light-emitting efficiency than the conventional light-emitting diode display device.

[0059] For example, in the embodiments of the present disclosure, after the thickness of the first organic layer of the light-emitting diode display device is increased, the voltage of the light-emitting diode display device has a small increase, but due to the enhancement of the intensity of the optical light emission of the light-emitting diode display device, the light-emitting efficiency of the light-emitting diode display device is significantly improved, so that the power consumption of the light-emitting diode display device is positive. At the same time, since the proportions of the thicknesses of the first, second, third and fourth organic layers are controlled, the balance of the transmission of holes and electrons is greatly optimized, thereby avoiding the quenching caused by the excessive amount of one of the holes and electrons, and further improving the life of the light-emitting diode display device.

[0060] For example, in the structure shown in FIG. 2, the first organic layer 2021 further includes a hole injection layer 2021c disposed on the side of the first hole transport layer 2021a close to the first electrode 201, and the material of the hole injection layer 2021c includes a hole transport material and a strong electron-accepting p-type dopant doped in the hole transport material. The hole injection layer 2021c can improve the efficiency of hole injection, thereby balancing the transmission of holes and electrons.

[0061] For example, in one example, the material of the hole injection layer 2021c includes at least one of hexacyanohexaazatriphenylene, 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4TCNQ), and 1,2,3-tris[(cyano)(4-cyano-2,3,5,6-tetrafluorophenyl)methylene]cyclopropane.

[0062] For example, in one example, the materials of the first hole transport layer 2021a, the second hole transport layer 2025a and the hole charge generation layer 2024b are all hole transport materials. The types of hole transport materials included in the first hole transport layer 2021a, the second hole transport layer 2025a and the hole charge generation layer 2024b can be the same or different, and the embodiments of the present disclosure are not limited in this regard.

[0063] For example, in one example, the hole transport materials included in the above-mentioned first hole transport layer 2021a, the second hole transport layer 2025a and the hole charge generation layer 2024b include at least one of arylamine materials, dimethylfluorene and carbazole materials.

[0064] For example, in one example, the hole transport material included in the first hole transport layer 2021a, the second hole transport layer 2025a, and the hole charge generation layer 2024b described above includes at least one of 4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (NPB), N,N'-bis(3-methylphenyl)-N,N'-diphenyl-[1,1'-biphenyl]-4,4'-diamine (TPD), 4-phenyl-4'-(9-phenylfluorene-9-yl)triphenylamine (BAFLP), 4,4'-bis[N-(9,9-dimethylfluorene-2-yl)-N-phenylamino]biphenyl (DFLDPBi), 4,4'-di(9-carbazolyl) biphenyl (CBP), and 9-phenyl-3-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazole (PCzPA).

[0065] For example, the first light emitting layer 2022 and the second light emitting layer 2026 described above can each include a red light emitting material, a green light emitting material, and a blue light emitting material. For example, the blue light emitting material includes at least one of a pyrene derivative, an anthracene derivative, a fluorene derivative, a perylene derivative, a styrylamine derivative, and a metal complex. The green light emitting material includes at least one of a coumarin dye, a quinacridone copper derivative, a polycyclic aromatic hydrocarbon, a diamine anthracene derivative, a carbazole derivative, and a metal complex. The red light emitting material includes at least one of 4-(dicyanomethylene)-2-methyl-6-(4-dimethylaminostyryl)-4H-pyran and a metal complex.

[0066] For example, in one example, the blue light emitting material includes at least one of N1,N6-di([1,1'-biphenyl]-2-yl)-N1,N6-di([1,1'-biphenyl]-4-yl)pyrene-1,6-diamine, 9,10-di-(2-naphthyl)anthracene (ADN), 2-methyl-9,10-di-2-naphthylanthracene (MADN), 2,5,8,11-tetra-tert-butylperylene (TBPe), 4,4'-bis[4-(diphenylamino)styryl]biphenyl (BDAVBi), 4,4'-bis[4-(di-p-tolylamino)styryl]biphenyl (DPAVBi), and bis(4,6-difluorophenylpyridine-C2,N)picolatoiridium (FIrpic).

[0067] For example, in one example, the green light emitting material includes at least one of coumarin 6 (C-6), coumarin 545T (C-525T), quinacridone copper (QA), N,N'-dimethylquinacridone (DMQA), 5,12-diphenyl naphthacene (DPT), N10,N10'-diphenyl-N10,N10'-diphenyl dicarboxy-9,9'-dianthracene-10,10'-diamine (abbreviated as: BA-NPB), tris(8-hydroxyquinoline) aluminum (III) (abbreviated as: Alq3), tris(2-phenylpyridine) iridium (Ir(ppy)3), and bis(2-phenylpyridine) iridium (Ir(ppy)2(acac)) acetylacetonate.

[0068] For example, in one example, the red light emitting material includes at least one of 4-(dicyanomethylene)-2-methyl-6-(4-dimethylaminostyryl)-4H-pyran (DCM), 4-(dicyanomethylene)-2-tert-butyl-6-(1,1,7,7-tetramethyljuglone-9-enyl)-4H-pyran (DCJTB), bis(1-phenylisoquinoline)(acetylacetonate) iridium (III) (Ir(piq)2(acac)), octaethylporphyrin platinum (abbreviated as: PtOEP), bis(2-(2'-benzothienyl)pyridine-N,C3')(acetylacetonate) iridium.

[0069] Of course, the red light emitting material, the green light emitting material, and the blue light emitting material provided by the embodiments of the present disclosure are not limited to the above-listed kinds, and can be other light emitting materials that emit light of the corresponding color.

[0070] For example, in the structure shown in FIG. 2, the third organic layer 2023 includes a first hole blocking layer 2023b disposed on a side of the first electron transport layer 2023a close to the first electrode 201. The second organic layer 2027 includes a second hole blocking layer 2027b disposed on a side of the second electron transport layer 2027a close to the first electrode 201, and the materials of the first electron transport layer 2023a, the first hole blocking layer 2023b, the second electron transport layer 2027a, the second hole blocking layer 2027b, and the electron charge generation layer 2024a are each selected from at least one of a benzimidazole derivative, an imidazopyridine derivative, a benzimidazophenanthridine derivative, a pyrimidine derivative, a triazine derivative, a quinoline derivative, an isoquinoline derivative, and a phenanthroline derivative.

[0071] For example, in one example, the materials of the first electron transport layer 2023a, the first hole blocking layer 2023b, the second electron transport layer 2027a, the second hole blocking layer 2027b and the electron charge generation layer 2024a are all selected from at least one of 2-(4-biphenyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (PBD), 1,3-bis[5-(p-tert-butylphenyl)-1,3,4-oxadiazol-2-yl]benzene (OXD-7), 3-(4-tert-butylphenyl)-4-phenyl-5-(4-biphenyl)-1,2,4-triazole (TAZ), 3-(4-tert-butylphenyl)-4-(4-ethylphenyl)-5-(4-biphenyl)-1,2,4-triazole (p-EtTAZ), 4,7-diphenyl-1,10-phenanthroline (BPhen), 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP), 4,4'-bis(5-methylbenzoxazol-2-yl)stilbene (BzOs).

[0072] For example, in the light emitting diode display device shown in FIG. 2, the light emitting diode display device 200 further includes an electron injection layer 208 disposed on a side of the second organic layer 2027 close to the second electrode 203, and the material of the electron injection layer 208 includes an alkali metal. In one example, the alkali metal includes Yb, Mg or Ca.

[0073] For example, in one example, the material of the electron injection layer 208 can further include LiF or other alkali metal compounds.

[0074] For example, as shown in FIG. 2, the fourth organic layer 2025 further includes a second electron blocking layer 2025b disposed on a side of the second hole transport layer 2025a close to the second light emitting layer 2026. The thickness of the second electron blocking layer 2025b is less than the thickness of the second hole transport layer 2025a. The ratio of the thickness of the second electron blocking layer 2025b to the thickness of the second hole transport layer 2025a in the portion corresponding to the blue sub-pixel ranges from 3% to 30%; the ratio of the thickness of the second electron blocking layer 2025b to the thickness of the second hole transport layer 2025a in the portion corresponding to the green sub-pixel ranges from 10% to 50%; and the ratio of the thickness of the second electron blocking layer 2025b to the thickness of the second hole transport layer 2025a in the portion corresponding to the red sub-pixel ranges from 30% to 75%. The light emitting diode display device 200 can reduce plasmonic polarization loss by setting the thickness of the second electron blocking layer 2025b to the thickness of the second hole transport layer 2025a in the portion corresponding to the sub-pixel of different colors within the above ratio range, so as to regulate the transport balance of electrons and holes while increasing the light out-coupling efficiency of the light emitting diode display device, to obtain a stacked device of the organic light emitting diode with optimal light emitting efficiency and longest lifetime.

[0075] For example, the materials of the first electron blocking layer 2021b and the second electron blocking layer 2025b can refer to the hole transport materials mentioned above, and embodiments of the present disclosure do not make any limitation thereto.

[0076] The light emitting diode display device provided by the embodiments of the present disclosure is described by comparing the following comparative examples and embodiments.

[0077] Comparative Example:

[0078] Corresponding to the blue light emitting element, the corresponding layer structure and thickness in the light emitting diode display device are anode 8 nm / hole injection layer 10 nm / first hole transport layer 20 nm / first electron blocking layer 10 nm / first blue light emitting layer 15 nm / first hole blocking layer 5 nm / first electron transport layer 30 nm / electron charge generation layer 18 nm / hole charge generation layer 9 nm / second hole transport layer 23 nm / second electron blocking layer 10 nm / second blue light emitting layer 15 nm / second hole blocking layer 5 nm / second electron transport layer 30 nm / electron injection layer 1 nm / cathode 14 nm / cover layer 70 nm.

[0079] Corresponding to the green light emitting element, the corresponding layer structure and thickness in the light emitting diode display device are anode 8 nm / hole injection layer 10 nm / first hole transport layer 20 nm / first electron blocking layer 12 nm / first green light emitting layer 40 nm / first hole blocking layer 5 nm / first electron transport layer 30 nm / electron charge generation layer 18 nm / hole charge generation layer 9 nm / second hole transport layer 23 nm / second electron blocking layer 12 nm / second green light emitting layer 40 nm / second hole blocking layer 5 nm / second electron transport layer 30 nm / electron injection layer 1 nm / cathode 14 nm / cover layer 70 nm.

[0080] Corresponding to the red light emitting element, the corresponding layer structure and thickness in the light emitting diode display device are anode 8 nm / hole injection layer 10 nm / first hole transport layer 20 nm / first electron blocking layer 14 nm / first red light emitting layer 60 nm / first hole blocking layer 5 nm / first electron transport layer 30 nm / electron charge generation layer 18 nm / hole charge generation layer 9 nm / second hole transport layer 23 nm / second electron blocking layer 14 nm / second red light emitting layer 60 nm / second hole blocking layer 5 nm / second electron transport layer 30 nm / electron injection layer 1 nm / cathode 14 nm / cover layer 70 nm.

[0081] Example One:

[0082] Corresponding to the blue light emitting element, the corresponding layers and thicknesses in the light emitting diode display device are anode 8 nm / hole injection layer 10 nm / first hole transport layer 120 nm / first electron blocking layer 10 nm / first blue light emitting layer 15 nm / first hole blocking layer 5 nm / first electron transport layer 20 nm / electron charge generation layer 18 nm / hole charge generation layer 9 nm / second hole transport layer 45 nm / second electron blocking layer 10 nm / second blue light emitting layer 15 nm / second hole blocking layer 5 nm / second electron transport layer 35 nm / electron injection layer 1 nm / cathode 14 nm / cover layer 70 nm.

[0083] Corresponding to the green light emitting element, the corresponding layers and thicknesses in the light emitting diode display device are anode 8 nm / hole injection layer 10 nm / first hole transport layer 120 nm / first electron blocking layer 30 nm / first green light emitting layer 40 nm / first hole blocking layer 5 nm / first electron transport layer 20 nm / electron charge generation layer 18 nm / hole charge generation layer 9 nm / second hole transport layer 45 nm / second electron blocking layer 20 nm / second green light emitting layer 40 nm / second hole blocking layer 5 nm / second electron transport layer 35 nm / electron injection layer 1 nm / cathode 14 nm / cover layer 70 nm.

[0084] Corresponding to the red light emitting element, the corresponding layers and thicknesses in the light emitting diode display device are anode 8 nm / hole injection layer 10 nm / first hole transport layer 120 nm / first electron blocking layer 50 nm / first red light emitting layer 60 nm / first hole blocking layer 5 nm / first electron transport layer 20 nm / electron charge generation layer 18 nm / hole charge generation layer 9 nm / second hole transport layer 45 nm / second electron blocking layer 30 nm / second red light emitting layer 60 nm / second hole blocking layer 5 nm / second electron transport layer 35 nm / electron injection layer 1 nm / cathode 14 nm / cover layer 70 nm.

[0085] In the above embodiment one, for the blue light emitting element, the thickness of the first organic layer is 148 nm, the thickness of the second organic layer is 40 nm, the thickness of the third organic layer is 25 nm, the thickness of the fourth organic layer is 55 nm, the thickness of the first hole transport layer is 120 nm, and the thickness of the first electron blocking layer is 10 nm. For the green light emitting element, the thickness of the first organic layer is 168 nm, the thickness of the second organic layer is 40 nm, the thickness of the third organic layer is 25 nm, the thickness of the fourth organic layer is 65 nm, the thickness of the first hole transport layer is 120 nm, and the thickness of the first electron blocking layer is 30 nm. For the red light emitting element, the thickness of the first organic layer is 188 nm, the thickness of the second organic layer is 40 nm, the thickness of the third organic layer is 25 nm, the thickness of the fourth organic layer is 75 nm, the thickness of the first hole transport layer is 120 nm, and the thickness of the first electron blocking layer is 50 nm.

[0086] In the above embodiment one, for the blue light emitting element, the ratio of the thickness of the fourth organic layer to the thickness of the first organic layer is 37.2%; for the green light emitting element, the ratio of the thickness of the fourth organic layer to the thickness of the first organic layer is 38.7%; and for the red light emitting element, the ratio of the thickness of the fourth organic layer to the thickness of the first organic layer is 39.9%. That is, for the blue light emitting element, the green light emitting element, and the red light emitting element, the ratio of the thickness of the fourth organic layer to the thickness of the first organic layer is within the range of 20%-60%, and is within the range of 30%-50%. For the blue light emitting element, the ratio of the thickness of the third organic layer to the thickness of the second organic layer is 62.5%; for the green light emitting element, the ratio of the thickness of the third organic layer to the thickness of the second organic layer is 62.5%; and for the red light emitting element, the ratio of the thickness of the third organic layer to the thickness of the second organic layer is 62.5%. That is, for the blue light emitting element, the green light emitting element, and the red light emitting element, the ratio of the thickness of the third organic layer to the thickness of the second organic layer is within the range of 50%-90%.

[0087] For example, in Table 3 below, the voltage, the light emitting efficiency, and the service life of the light emitting diode display device provided by the embodiment one of the present disclosure when the light emitting elements corresponding to different colors are separately turned on, and the voltage, the light emitting efficiency, and the service life of the light emitting diode display device in the comparative example are studied by using optical simulation experiments.

[0088] Table 3: Comparison of the voltage, the light emitting efficiency, and the service life of the light emitting diode display device provided by the embodiment one of the present disclosure and the voltage, the light emitting efficiency, and the service life of the light emitting diode display device in the comparative example.

[0089] Compared with the structure of the light emitting diode display device in the above-mentioned embodiment one and the comparative example, the voltage of the light emitting diode display device in the embodiment one has a small increase, but due to the enhancement of the optical light emission, the display efficiency of the light emitting diode display device is significantly improved, and the overall power consumption is positive. At the same time, due to the adjustment of the ratio range of the thickness of the fourth organic layer to the thickness of the first organic layer, the ratio range of the thickness of the third organic layer to the thickness of the second organic layer in the light emitting diode display device in the embodiment one, the balance of the transmission of holes and electrons is greatly optimized, the quenching caused by too many excitons is avoided, and the service life of the light emitting diode display device is greatly improved.

[0090] Embodiment two:

[0091] For the blue light emitting element, the thickness of the first organic layer is 128 nm, the thickness of the second organic layer is 40 nm, the thickness of the third organic layer is 25 nm, the thickness of the fourth organic layer is 75 nm, the thickness of the first hole transport layer is 100 nm, and the thickness of the first electron blocking layer is 10 nm.

[0092] For the green light emitting element, the thickness of the first organic layer is 148 nm, the thickness of the second organic layer is 40 nm, the thickness of the third organic layer is 25 nm, the thickness of the fourth organic layer is 85 nm, the thickness of the first hole transport layer is 100 nm, and the thickness of the first electron blocking layer is 30 nm.

[0093] For the red light emitting element, the thickness of the first organic layer is 168 nm, the thickness of the second organic layer is 40 nm, the thickness of the third organic layer is 25 nm, the thickness of the fourth organic layer is 95 nm, the thickness of the first hole transport layer is 100 nm, and the thickness of the first electron blocking layer is 50 nm.

[0094] That is, in the above-mentioned embodiment two, for the blue light emitting element, the green light emitting element and the red light emitting element, the ratio range of the thickness of the fourth organic layer to the thickness of the first organic layer is within 20%-60%, and the ratio range of the thickness of the third organic layer to the thickness of the second organic layer is within 50%-90%.

[0095] Embodiment three:

[0096] For the blue light emitting element, the thickness of the first organic layer is 168 nm, the thickness of the second organic layer is 40 nm, the thickness of the third organic layer is 25 nm, the thickness of the fourth organic layer is 35 nm, the thickness of the first hole transport layer is 140 nm, and the thickness of the first electron blocking layer is 10 nm.

[0097] For the green light emitting element, the thickness of the first organic layer was 188 nm, the thickness of the second organic layer was 40 nm, the thickness of the third organic layer was 25 nm, the thickness of the fourth organic layer was 45 nm, the thickness of the first hole transport layer was 140 nm, and the thickness of the first electron blocking layer was 10 nm.

[0098] For the red light emitting element, the thickness of the first organic layer was 208 nm, the thickness of the second organic layer was 40 nm, the thickness of the third organic layer was 25 nm, the thickness of the fourth organic layer was 55 nm, the thickness of the first hole transport layer was 140 nm, and the thickness of the first electron blocking layer was 10 nm.

[0099] That is, in the above-described Example Three, for the blue light emitting element, the green light emitting element, and the red light emitting element, the ratio of the thickness of the fourth organic layer to the thickness of the first organic layer was within the range of 20% to 60%, and the ratio of the thickness of the third organic layer to the thickness of the second organic layer was within the range of 50% to 90%.

[0100] Example Four:

[0101] For the blue light emitting element, the thickness of the first organic layer was 148 nm, the thickness of the second organic layer was 35 nm, the thickness of the third organic layer was 30 nm, the thickness of the fourth organic layer was 55 nm, the thickness of the first hole transport layer was 120 nm, and the thickness of the first electron blocking layer was 10 nm.

[0102] For the green light emitting element, the thickness of the first organic layer was 168 nm, the thickness of the second organic layer was 35 nm, the thickness of the third organic layer was 30 nm, the thickness of the fourth organic layer was 65 nm, the thickness of the first hole transport layer was 120 nm, and the thickness of the first electron blocking layer was 30 nm.

[0103] For the red light emitting element, the thickness of the first organic layer was 188 nm, the thickness of the second organic layer was 35 nm, the thickness of the third organic layer was 30 nm, the thickness of the fourth organic layer was 75 nm, the thickness of the first hole transport layer was 120 nm, and the thickness of the first electron blocking layer was 50 nm.

[0104] That is, in the above-described Example Four, for the blue light emitting element, the green light emitting element, and the red light emitting element, the ratio of the thickness of the fourth organic layer to the thickness of the first organic layer was within the range of 20% to 60%, and the ratio of the thickness of the third organic layer to the thickness of the second organic layer was within the range of 50% to 90%.

[0105] Example Five:

[0106] For the blue light emitting element, the thickness of the first organic layer was 148 nm, the thickness of the second organic layer was 40 nm, the thickness of the third organic layer was 25 nm, the thickness of the fourth organic layer was 55 nm, the thickness of the first hole transport layer was 100 nm, and the thickness of the first electron blocking layer was 30 nm.

[0107] For the green light emitting element, the thickness of the first organic layer was 148 nm, the thickness of the second organic layer was 40 nm, the thickness of the third organic layer was 25 nm, the thickness of the fourth organic layer was 55 nm, the thickness of the first hole transport layer was 100 nm, and the thickness of the first electron blocking layer was 50 nm.

[0108] For the red light emitting element, the thickness of the first organic layer was 148 nm, the thickness of the second organic layer was 40 nm, the thickness of the third organic layer was 25 nm, the thickness of the fourth organic layer was 55 nm, the thickness of the first hole transport layer was 100 nm, and the thickness of the first electron blocking layer was 70 nm.

[0109] That is, in Embodiment Two described above, for the blue light emitting element, the green light emitting element, and the red light emitting element, the ratio of the thickness of the fourth organic layer to the thickness of the first organic layer was within the range of 20% to 60%, and the ratio of the thickness of the third organic layer to the thickness of the second organic layer was within the range of 50% to 90%.

[0110] For example, in Table Four below, the voltage, the light emitting efficiency, and the lifespan of the light emitting diode display device provided by Embodiments One to Five of the present disclosure, which correspond to the sub-pixels of different colors and have different thicknesses of the first organic layer, the second organic layer, the third organic layer, the fourth organic layer, the first hole transport layer, and the first electron blocking layer, were studied using optical simulation experiments.

[0111] Table Four: Comparison of the voltage, the light emitting efficiency, and the lifespan of the light emitting diode display device provided by Embodiments One to Five of the present disclosure.

[0112] The voltage, the light emitting efficiency, and the lifespan of the light emitting diode display device provided by Embodiments Two to Five of the present disclosure, which correspond to the sub-pixels of different colors and have different thicknesses of the first organic layer, the second organic layer, the third organic layer, the fourth organic layer, the first hole transport layer, and the first electron blocking layer, were studied using optical simulation experiments in Table Four described above, and the voltage, the light emitting efficiency, and the lifespan of the light emitting diode display device in Embodiment One were compared.

[0113] In Example Two, the thickness of the first organic layer is reduced and the thickness of the fourth organic layer is increased, while the overall thickness of the light emitting diode display device remains unchanged. In Example Two, the ratio of the thickness of the fourth organic layer to the thickness of the first organic layer is 58.6% for the blue light emitting element, 57.4% for the green light emitting element, and 56.5% for the red light emitting element, all of which are within the range of 20%-60%, but not within the range of 30%-50%, and all of which are close to the upper limit of 60%. As the first light emitting layer is closer to the anode and deviates from the optimal position of microcavity enhancement, the display efficiency of the light emitting diode display device decreases. In addition, as the thickness of the first electron blocking layer does not change but the thickness of the first hole transport layer changes, the distribution of excitons is less balanced, and the service life of the light emitting diode display device also decreases slightly.

[0114] In Example Three, the thickness of the first organic layer is increased and the thickness of the fourth organic layer is reduced, while the overall thickness of the light emitting diode display device remains unchanged. In Example Three, the ratio of the thickness of the fourth organic layer to the thickness of the first organic layer is 20.8% for the blue light emitting element, 23.9% for the green light emitting element, and 26.4% for the red light emitting element, all of which are within the range of 20%-60%, but not within the range of 30%-50%, and all of which are close to the lower limit of 20%. Although the first light emitting layer is further away from the anode, reducing the influence of optical waveguide and surface plasmon polariton, as the optimal position of microcavity enhancement is deviated, the display efficiency of the light emitting diode display device also decreases slightly. In addition, as the thickness of the first electron blocking layer does not change but the thickness of the first hole transport layer changes, the distribution of excitons is less balanced, and the service life of the light emitting diode display device also decreases slightly.

[0115] In Example Four, the thickness of the second organic layer is reduced and the thickness of the third organic layer is increased, and the overall thickness of the light emitting diode display device remains unchanged. In Example Four, the ratio of the thickness of the third organic layer to the thickness of the second organic layer is 85.7% for the blue light emitting element, 85.7% for the green light emitting element, and 85.7% for the red light emitting element. The ratio of the thickness of the third organic layer to the thickness of the second organic layer is in the range of 50% to 90%, but not in the range of 60% to 80%. At this time, the display efficiency and the service life of the light emitting diode display device are slightly affected due to the deviation of the first light emitting layer from the optimal position and the unbalanced exciton transmission, but the effect is not great because the thickness of the second organic layer and the thickness of the third organic layer are changed slightly.

[0116] In Example Five, the thickness of the first organic layer, the thickness of the second organic layer, the thickness of the third organic layer, and the thickness of the fourth organic layer remain unchanged, the thickness of the first electron blocking layer is increased, and the thickness of the first hole transport layer is reduced. The ratio of the thickness of the first electron blocking layer to the thickness of the first hole transport layer is 3% to 30% for the blue light emitting element, 10% to 50% for the green light emitting element, and 30% to 75% for the red light emitting element, i.e., the following relationships are met: blue light emitting element 3% to 30%, green light emitting element 10% to 50%, and red light emitting element 30% to 75%. However, the overall is close to the upper limit of the light emitting element of each color. Since the material of the first electron blocking layer has a lower hole mobility than the material of the hole transport layer, especially the first electron blocking layer in the blue light emitting element, the voltage of the light emitting diode display device rises, but the luminous efficiency and the service life are not affected.

[0117] In the embodiments of the present disclosure, the light emitting diode display device is exemplified by a double-stacked light emitting diode display device, but the corresponding thickness rules are also applicable to triple-stacked and above stacked light emitting devices. For triple-stacked and above stacked light emitting devices, please refer to the relevant trends in the above, which will not be repeated here.

[0118] The display device provided by at least one of the embodiments of the present disclosure comprises the light-emitting diode display device described above. FIG. 3 is a schematic diagram of a display device provided by an embodiment of the present disclosure. As shown in FIG. 3, the display device 300 comprises the light-emitting diode display device 200 described above. Thus, the display device 300 can improve the display efficiency and service life of the light-emitting diode display device by making the thickness of the first part of the first organic layer corresponding to the blue sub-pixel range from 120 nm to 180 nm, the thickness of the second part of the first organic layer corresponding to the green sub-pixel range from 140 nm to 180 nm, and the thickness of the third part of the first organic layer corresponding to the red sub-pixel range from 160 nm to 240 nm, so that the electron transport and hole transport can reach a better balance.

[0119] For example, in some examples, the display device can further comprise a functional component located on a side of the first electrode away from the second electrode. For example, the functional component comprises at least one of a camera module (e.g., a front-facing camera module), a 3D structured light module (e.g., a 3D structured light sensor), a time-of-flight 3D imaging module (e.g., a time-of-flight sensor), an infrared sensing module (e.g., an infrared sensing sensor), and the like. The display device can also be any product or component with display function, such as a smartphone, a tablet computer, a television, a display, a notebook computer, a digital photo frame, a navigator, and the like.

[0120] The light-emitting diode display device and the display device provided by at least one of the embodiments of the present disclosure can improve the display efficiency and service life of the light-emitting diode display device by making the thickness of the first part of the first organic layer corresponding to the blue sub-pixel range from 120 nm to 180 nm, the thickness of the second part of the first organic layer corresponding to the green sub-pixel range from 140 nm to 180 nm, and the thickness of the third part of the first organic layer corresponding to the red sub-pixel range from 160 nm to 240 nm, so that the electron transport and hole transport can reach a better balance.

[0121] The following points need to be explained:

[0122] (1) The drawings of the embodiments of the present disclosure only involve the structures involved in the embodiments of the present disclosure, and other structures can be referred to the general design.

[0123] (2) For the sake of clarity, the thickness of a layer or region is exaggerated or reduced in the drawings used to describe the embodiments of the present disclosure, i.e., these drawings are not drawn according to the actual scale.

[0124] (3) In the case of no conflict, the embodiments of the present disclosure and the features in the embodiments can be combined with each other to obtain new embodiments.

[0125] The above merely describes a specific implementation of the present disclosure, but the protection scope of the present disclosure is not limited thereto, and the protection scope of the present disclosure should be subject to the protection scope of the claims.

Claims

1. A light emitting diode display device, comprising: The first electrode, the light-emitting functional layer, and the second electrode are sequentially stacked in the first direction, wherein The light-emitting functional layer comprises a first organic layer, a first light-emitting layer, a third organic layer, a charge generation layer, a fourth organic layer, a second light-emitting layer, and a second organic layer, which are sequentially stacked in the first direction; The first organic layer has a first portion corresponding to the blue sub-pixel, a second portion corresponding to the green sub-pixel, and a third portion corresponding to the red sub-pixel, wherein the thickness of the first portion ranges from 120 nm to 180 nm, the thickness of the second portion ranges from 140 nm to 180 nm, and the thickness of the third portion ranges from 160 nm to 240 nm.

2. The light-emitting diode display device according to claim 1, wherein The first organic layer comprises a first hole transport layer, the fourth organic layer comprises a second hole transport layer, the charge generation layer comprises an electron charge generation layer and a hole charge generation layer which are sequentially stacked, the electron charge generation layer is closer to the first organic layer than the hole charge generation layer, the second hole transport layer and the hole charge generation layer are adjacent, and the thickness of the first hole transport layer is greater than the thickness of the second hole transport layer.

3. The light emitting diode display device according to claim 2, wherein, The third organic layer comprises a first electron transport layer, the second organic layer comprises a second electron transport layer, the first electron transport layer and the electron charge generation layer are adjacent, and the thickness of the second electron transport layer is greater than the thickness of the first electron transport layer.

4. The light emitting diode display device according to any one of claims 1 to 3, wherein The thickness of the first organic layer is greater than the thickness of the fourth organic layer, and the thickness of the second organic layer is greater than the thickness of the third organic layer.

5. The light emitting diode display device according to claim 4, wherein, The ratio of the thickness of the fourth organic layer to the thickness of the first organic layer ranges from 20% to 60%, and the ratio of the thickness of the third organic layer to the thickness of the second organic layer ranges from 50% to 90%.

6. The light emitting diode display device according to claim 5, wherein, The ratio of the thickness of the fourth organic layer to the thickness of the first organic layer ranges from 30% to 50%, and the ratio of the thickness of the third organic layer to the thickness of the second organic layer ranges from 60% to 80%.

7. The light emitting diode display device according to claim 2, wherein, The first organic layer further comprises a first electron blocking layer disposed on the side of the first hole transport layer away from the first electrode, wherein the ratio of the thickness of the first electron blocking layer to the thickness of the first hole transport layer ranges from 3% to 30% for the portion corresponding to the blue sub-pixel, the ratio of the thickness of the first electron blocking layer to the thickness of the first hole transport layer ranges from 10% to 50% for the portion corresponding to the green sub-pixel, and the ratio of the thickness of the first electron blocking layer to the thickness of the first hole transport layer ranges from 30% to 75% for the portion corresponding to the red sub-pixel.

8. The light emitting diode display device according to claim 7, wherein, The first organic layer further comprises a hole injection layer disposed on the side of the first hole transport layer close to the first electrode, and the material of the hole injection layer comprises a hole transport material and a strong-electron-accepting p-type dopant doped in the hole transport material.

9. The light emitting diode display device according to claim 8, wherein, The material of the hole injection layer includes at least one of hexacyanohexaazatriphenylene, 2,3,5,6-tetrafluoro-7,7,8,8-tetracyano-p-quinodimethane (F4TCNQ), and 1,2,3-tris[(cyano)(4-cyano-2,3,5,6-tetrafluorophenyl)methylene]cyclopropane.

10. The light emitting diode display device according to claim 2, wherein, The materials of the first hole transport layer, the second hole transport layer, and the hole charge generation layer are all hole transport materials.

11. The light emitting diode display device according to claim 10, wherein, The hole transport material includes at least one of arylamine-based material, dimethylfluorene, and carbazole-based material.

12. The light emitting diode display device according to claim 11, wherein, The hole transport material includes at least one of 4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (NPB), N,N'-bis(3-methylphenyl)-N,N'-diphenyl-[1,1'-biphenyl]-4,4'-diamine (TPD), 4-phenyl-4'-(9-phenylfluorene-9-yl)triphenylamine (BAFLP), 4,4'-bis[N-(9,9-dimethylfluorene-2-yl)-N-phenylamino]biphenyl (DFLDPBi), 4,4'-di(9-carbazolyl) biphenyl (CBP), and 9-phenyl-3-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazole (PCzPA).

13. The light emitting diode display device of claim 1, wherein, The first light emitting layer and the second light emitting layer each include a red light emitting material, a green light emitting material, and a blue light emitting material. The blue light emitting material includes at least one of pyrene derivative, anthracene derivative, fluorene derivative, perylene derivative, styrylamine derivative, and metal complex. The green light emitting material includes at least one of coumarin dye, quinacridone copper derivative, polycyclic aromatic hydrocarbon, anthracene derivative, carbazole derivative, and metal complex. The red light emitting material includes at least one of 4-(dicyanomethylene)-2-methyl-6-(4-dimethylaminostyryl)-4H-pyran (DCM) and metal complex.

14. The light emitting diode display device according to claim 13, wherein, The blue light emitting material includes at least one of N1,N6-di([1,1'-biphenyl]-2-yl)-N1,N6-di([1,1'-biphenyl]-4-yl)pyrene-1,6-diamine, 9,10-di-(2-naphthyl)anthracene (ADN), 2-methyl-9,10-di-2-naphthylanthracene (MADN), 2,5,8,11-tetra-tert-butyl perylene (TBPe), 4,4'-bis[4-(diphenylamino)styryl]biphenyl (BDAV Bi), 4,4'-bis[4-(diphenylamino)styryl]biphenyl (DPAVBi), and bis(4,6-difluorophenylpyridine-C2,N)picolinate iridium (FIrpic).

15. The light emitting diode display device according to claim 13, wherein, The green light emitting material includes at least one of coumarin 6 (C-6), coumarin 545T (C-525T), quinacridone copper (QA), N,N'-dimethylquinacridone (DMQA), 5,12-diphenyl naphthacene (DPT), N10,N10'-diphenyl-N10,N10'-diphenyl dicarboxylic acid-9,9'-di-anthracene-10,10'-diamine (abbreviation: BA-NPB), tris(8-hydroxyquinoline) aluminum (III) (abbreviation: Alq3), tris(2-phenylpyridine) iridium (Ir(ppy)3), and bis(2-phenylpyridine) iridium acetylacetonate (Ir(ppy)2(acac)).

16. The light emitting diode display device according to claim 13, wherein, The red light emitting material includes at least one of 4-(dicyanomethylene)-2-methyl-6-(4-dimethylaminostyryl)-4H-pyran (DCM), 4-(dicyanomethylene)-2-tert-butyl-6-(1,1,7,7-tetramethylguilonium-9-enyl)-4H-pyran (DCJTB), bis(1-phenylisoquinoline)(acetylacetonate) iridium (III) (Ir(piq)2(acac)), octaethylporphyrin platinum (abbreviation: PtOEP), and bis(2-(2'-benzothienyl)pyridine-N,C3')(acetylacetonate) iridium.

17. The light emitting diode display device according to claim 3, wherein, The third organic layer includes a first hole blocking layer disposed on a side of the first electron transport layer close to the first electrode, and the second organic layer includes a second hole blocking layer disposed on a side of the second electron transport layer close to the first electrode, and materials of the first electron transport layer, the first hole blocking layer, the second electron transport layer, the second hole blocking layer, and the electron charge generation layer are each selected from at least one of a benzimidazole derivative, an imidazopyridine derivative, a benzimidazophenanthridine derivative, a pyrimidine derivative, a triazine derivative, a quinoline derivative, an isoquinoline derivative, and a phenanthroline derivative.

18. The light emitting diode display device according to claim 17, wherein, The materials of the first electron transport layer, the first hole blocking layer, the second electron transport layer, the second hole blocking layer, and the electron charge generation layer are each selected from at least one of 2-(4-biphenyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (PBD), 1,3-bis[5-(p-tert-butylphenyl)-1,3,4-oxadiazol-2-yl]benzene (OXD-7), 3-(4-tert-butylphenyl)-4-phenyl-5-(4-biphenylyl)-1,2,4-triazole (TAZ), 3-(4-tert-butylphenyl)-4-(4-ethylphenyl)-5-(4-biphenylyl)-1,2,4-triazole (p-EtTAZ), 4,7-diphenyl-1,10-phenanthroline (BPhen), 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP), and 4,4'-bis(5-methylbenzoxazol-2-yl)stilbene (BzOs).

19. The light emitting diode display device according to claim 17, further comprising an electron injection layer disposed on a side of the second organic layer proximate to the second electrode, wherein, The material of the electron injection layer includes an alkali metal.

20. The light emitting diode display device according to claim 1, wherein, The fourth organic layer further includes a second electron blocking layer disposed on a side of the second hole transport layer proximate to the second light emitting layer.

21. A display device comprising the light emitting diode display device according to any one of claims 1 to 20.

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