Organic light-emitting structure, display panel and display device

Abstract

The invention discloses an organic light-emitting structure, a display panel and a display device, and belongs to the technical field of OLED (organic light-emitting diode) devices. The organic light-emitting structure comprises a first light-emitting layer, a second light-emitting layer and a third light-emitting layer which are stacked; the first light-emitting layer comprises a selective light-emitting layer, the second light-emitting layer comprises a first green light-emitting layer and a first blue light-emitting layer which are stacked, and the projection of the first green light-emitting layer on the substrate falls into the projection of the first blue light-emitting layer on the substrate; the third light-emitting layer comprises a first red light-emitting layer and a second blue light-emitting layer which are stacked, and the projection of the first red light-emitting layer on the substrate falls into the projection of the first blue light-emitting layer on the substrate. According to the organic light-emitting structure, when the organic light-emitting structure emits red light and green light, the blue light-emitting layer only serves as a common transmission layer and does not emit light, the utilization rate of red and green excitons can be increased, and the red and green light-emitting efficiency can be improved; when blue light is emitted, the red-green light-emitting layer does not affect the blue light, brightness loss caused by the color film is reduced, and the light-emitting efficiency of the blue light is improved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of OLED devices, and particularly relates to an organic light-emitting structure, a display panel and a display device. BACKGROUND

[0002] The silicon-based OLED display device is a new generation of micro display technology combining semiconductor silicon-based technology and organic light-emitting diode (OLED), and its core advantage is to integrate a single crystal silicon substrate and a high-precision CMOS driving circuit to achieve ultra-high pixel density and miniaturization design that cannot be achieved by traditional display technology.

[0003] With the gradual increase of the pixel density of the OLED display device, higher requirements are put forward for the existing OLED structure design. The existing mainstream silicon-based OLED structure mainly adopts the combination of white organic light-emitting diode and color film, and the light-emitting layer in the OLED is a common layer, and then the microcavity parameters of the device are adjusted by different thicknesses of indium tin oxide layers to realize red, blue and green single color light emission. Although the white organic light-emitting diode and the color film can realize different color light emission, correspondingly, the hierarchical structure of the color film itself will cause a certain degree of brightness loss, affecting the light-emitting efficiency of the OLED device. SUMMARY

[0004] In view of one or more of the above defects or improvement needs of the prior art, the present application provides an organic light-emitting structure to solve the problem that the color film in the existing OLED display device affects the light-emitting efficiency of the OLED.

[0005] To achieve the above-mentioned purpose, the present application provides an organic light-emitting structure, which comprises: a first light-emitting layer, a second light-emitting layer and a third light-emitting layer which are sequentially stacked; The first light-emitting layer comprises a selective light-emitting layer, and the selective light-emitting layer is one of a red light-emitting layer, a green light-emitting layer or a yellow light-emitting layer. The second light-emitting layer comprises a first green light-emitting layer and a first blue light-emitting layer which are stacked; the projection of the first green light-emitting layer on the substrate falls within the projection of the second blue light-emitting layer on the substrate.

[0006] As a further improvement of the present application, the first green light-emitting layer is arranged on the side of the first blue light-emitting layer close to the first light-emitting layer.

[0007] As a further improvement of the present application, the first green light-emitting layer is arranged on the side of the first blue light-emitting layer away from the first light-emitting layer.

[0008] As a further improvement of the present application, the second light-emitting layer further comprises a third blue light-emitting layer, which is arranged on the side of the first green light-emitting layer away from the first blue light-emitting layer, and the projection of the third blue light-emitting layer on the substrate is the same as the projection of the first blue light-emitting layer on the substrate.

[0009] As a further improvement of the present application, the first red light-emitting layer is arranged on the side of the second blue light-emitting layer close to the first light-emitting layer.

[0010] As a further improvement of the present application, the first red light-emitting layer is arranged on the side of the second blue light-emitting layer away from the first light-emitting layer.

[0011] As a further improvement of the present application, the third light-emitting layer further comprises a fourth blue light-emitting layer; the fourth blue light-emitting layer is arranged on the side of the first red light-emitting layer away from the second blue light-emitting layer, and the projection of the fourth blue light-emitting layer on the substrate is the same as the projection of the second blue light-emitting layer on the substrate.

[0012] The present application further comprises a display panel comprising a substrate, an anode layer and the organic light-emitting structure arranged in layers.

[0013] As a further improvement of the present application, the anode layer comprises a first indium tin oxide layer, a second indium tin oxide layer and a third indium tin oxide layer arranged side by side; The projections of the first blue light-emitting layer and the second blue light-emitting layer on the substrate cover the first indium tin oxide layer, the second indium tin oxide layer and the third indium tin oxide layer; The projections of the selective light-emitting layer, the first green light-emitting layer and the first red light-emitting layer on the substrate cover the second indium tin oxide layer and the third indium tin oxide layer.

[0014] As a further improvement of the present application, a color filter is further comprised, and the projection of the color filter on the substrate is the same as the projection of the selective light-emitting layer on the substrate.

[0015] The present application further comprises a display device comprising the display panel.

[0016] The above technical features can be combined with each other as long as they do not conflict with each other.

[0017] Overall, the above technical solutions conceived by the present application have the following beneficial effects compared with the prior art: (1) The organic light-emitting structure in the application replaces the blue light-emitting layer with the selective light-emitting layer by deposition, so that when the OLED device emits red light or green light, the first blue light-emitting layer and the second blue light-emitting layer only serve as common transport layers and do not emit light, which can improve the utilization rate of red and green excitons and the red and green light-emitting efficiency under the same voltage compared with the conventional three-layer structure; in addition, the projection of the first green light-emitting layer and the first red light-emitting layer on the substrate falls completely within the projection of the blue light-emitting layer, so that there is no red and green light-emitting layer above the blue light-emitting area, and the blue light-emitting area can directly emit blue light without the need for a color film to filter the interference of red and green light, reducing the loss of blue light by the color film; at the same time, the double light-emitting layer structure can further widen the recombination interval and improve the blue light lifetime, further improving the blue light-emitting efficiency of the OLED device. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 is a whole structure schematic diagram of a multi-layer OLED device in an embodiment of the application; Figure 2 is a whole structure schematic diagram of a second multi-layer OLED device in an embodiment of the application; Figure 3 is a whole structure schematic diagram of a third multi-layer OLED device in an embodiment of the application; Figure 4 is a whole structure schematic diagram of a fourth multi-layer OLED device in an embodiment of the application; Figure 5 is a whole structure schematic diagram of a fifth multi-layer OLED device in an embodiment of the application; Figure 6 is a schematic diagram of the arrangement structure of the first green light-emitting layer and the first red light-emitting layer in the FMM template in an embodiment of the application.

[0019] In all the drawings, the same reference signs represent the same technical features, specifically: 1, selective light-emitting layer; 2, first green light-emitting layer; 3, first blue light-emitting layer; 4, first red light-emitting layer; 5, second blue light-emitting layer; 6, third blue light-emitting layer; 7, fourth blue light-emitting layer; 8, first indium tin oxide layer; 9, second indium tin oxide layer; 10, third indium tin oxide layer; 11, color film; 12, cathode layer; 13, first hole injection layer; 14, first hole transport layer; 15, first electron transport layer; 16, first N-type charge generation layer; 17, first P-type charge generation layer; 18, second hole transport layer; 19, second electron transport layer; 20, second N-type charge generation layer; 21, second P-type charge generation layer; 22, third hole transport layer; 23, third electron transport layer; 24, first electron injection layer; 25, light extraction layer. DETAILED DESCRIPTION

[0020] In order to make the objects, technical solutions and advantages of the present application clearer, the following further describes the present application with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and should not be used to limit the present application. In addition, the technical features involved in the various embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.

[0021] The terms "first", "second" are only for descriptive purposes and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined with "first", "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "a plurality of" is at least two, such as two, three, etc., unless otherwise explicitly specified and limited.

[0022] In the present application, unless otherwise explicitly specified and limited, the "on" or "under" of the first feature to the second feature can be that the first and second features are in direct contact, or the first and second features are indirectly in contact through an intermediate medium. Moreover, the "over", "above" and "on" of the first feature to the second feature can be that the first feature is directly above or obliquely above the second feature, or only indicates that the horizontal height of the first feature is higher than that of the second feature. The "under", "below" and "under" of the first feature to the second feature can be that the first feature is directly below or obliquely below the second feature, or only indicates that the horizontal height of the first feature is less than that of the second feature.

[0023] Embodiments: Please refer to Figure 1 The organic light-emitting structure in the preferred embodiment of the present application comprises a first light-emitting layer, a second light-emitting layer and a third light-emitting layer which are sequentially stacked; the first light-emitting layer comprises a selective light-emitting layer 1, and the selective light-emitting layer 1 is one of a red light-emitting layer, a green light-emitting layer or a yellow light-emitting layer; the second light-emitting layer comprises a first green light-emitting layer 2 and a first blue light-emitting layer 3 which are stacked; and the projection of the first green light-emitting layer 2 on the substrate falls within the projection of the first blue light-emitting layer 3 on the substrate; the third light-emitting layer comprises a first red light-emitting layer 4 and a second blue light-emitting layer 5 which are stacked, and the projection of the first red light-emitting layer 4 on the substrate falls within the projection of the second blue light-emitting layer 5 on the substrate.

[0024] The organic light-emitting structure of this invention uses a selective light-emitting layer 1 to replace the blue light-emitting layer. This allows the first blue light-emitting layer 3 and the second blue light-emitting layer 5 to function only as common transport layers and not emit light when the OLED device emits red or green light. Compared to the conventional triple-layer structure, this improves the utilization rate of red and green excitons under the same voltage, thereby increasing the red and green light emission efficiency. In addition, this invention ensures that the projections of the first green light-emitting layer 2 and the first red light-emitting layer 4 on the substrate fall completely within the projection of the blue light-emitting layer. This eliminates the need for red and green light-emitting layers above the blue light-emitting area, allowing the blue light-emitting area to emit blue light directly without the need for a color filter 11 to filter out red and green light interference, reducing the loss of blue light by the color filter 11. At the same time, the dual-emitting-layer structure can further widen the recombination range, improve the blue light lifetime, and further enhance the blue light emission efficiency in the OLED device.

[0025] Optionally, in this invention, the layers of the organic light-emitting structure are formed sequentially through a deposition process. The projections of the first red light-emitting layer 4 and the first green light-emitting layer 2 in the substrate direction completely fall within the projections of the first blue light-emitting layer 3 and the second blue light-emitting layer 5. The area of ​​the first red light-emitting layer 4 and the first green light-emitting layer 2 on the plane is smaller than that of the first blue light-emitting layer 3 and the second blue light-emitting layer 5. To avoid vacancy defects in the layer structure of the organic light-emitting structure, the vacancy areas of the first red light-emitting layer 4 and the first green light-emitting layer 2 relative to the first blue light-emitting layer 3 and the second blue light-emitting layer 5 are filled by an upper deposition material to avoid the formation of defects inside the organic light-emitting structure.

[0026] Furthermore, as an optional embodiment of the present invention, the first green light-emitting layer 2 is disposed on the side of the first blue light-emitting layer 3 near the first light-emitting layer, such as... Figure 2 As shown. Alternatively, the first green light-emitting layer 2 is disposed on the side of the first blue light-emitting layer 3 away from the first light-emitting layer, as shown. Figure 1 As shown. The first blue light-emitting layer 3 is mainly used to cooperate with the cathode layer 12 and the anode layer to emit light. The stacking order of the first blue light-emitting layer 3 and the first green light-emitting layer 2 on the substrate does not affect the red and green light emission. Therefore, the first green light-emitting layer 2 is disposed on the side of the first blue light-emitting layer 3 close to the first light-emitting layer, or the first green light-emitting layer 2 is disposed on the side of the first blue light-emitting layer 3 away from the first light-emitting layer.

[0027] Furthermore, such as Figure 5As shown, as an optional embodiment of the present application, the second light-emitting layer in the present application further comprises a third blue light-emitting layer 6, which is arranged on the side of the first green light-emitting layer 2 away from the first blue light-emitting layer 3, and the projection of the third blue light-emitting layer 6 on the substrate is the same as the projection of the first blue light-emitting layer 3 on the substrate. In addition to arranging the blue light-emitting layer on one side of the first green light-emitting layer 2, the first blue light-emitting layer 3 and the third blue light-emitting layer 6 can also be arranged on both sides of the first green light-emitting layer 2 respectively, and the first blue light-emitting layer 3 and the third blue light-emitting layer 6 serve as a common transport layer structure, which can make the first green light-emitting layer 2 have high composite excitons and improve the light-emitting intensity of green light.

[0028] Optionally, the first blue light-emitting layer 3 in the present application adopts a hole type host, which is prepared by using TCTA or mCP, and the overall thickness is 10-15 nm. Optionally, the third blue light-emitting layer 6 adopts an electron type host, which is prepared by using CPB or Bepp2, and the overall thickness is 10-15 nm.

[0029] Further, as an optional embodiment of the present application, the first red light-emitting layer 4 in the present application is arranged on the side of the second blue light-emitting layer 5 close to the first light-emitting layer, as shown in Figure 3 , Figure 4 Alternatively, the first red light-emitting layer 4 is arranged on the side of the second blue light-emitting layer 5 away from the first light-emitting layer, as shown in Figure 1 The stacking order of the first red light-emitting layer 4 and the second blue light-emitting layer 5 in the projection direction of the substrate does not affect the red light and blue light emission, so the positions of the two can be adjusted, that is, the first red light-emitting layer 4 is arranged on the side of the second blue light-emitting layer 5 close to the first light-emitting layer, or the first red light-emitting layer 4 is arranged on the side of the second blue light-emitting layer 5 away from the first light-emitting layer.

[0030] Further, as an optional embodiment of the present application, the third light-emitting layer further comprises a fourth blue light-emitting layer 7; the fourth blue light-emitting layer 7 is arranged on the side of the first red light-emitting layer 4 away from the second blue light-emitting layer 5. Similarly, for the third light-emitting layer, the second blue light-emitting layer 5 and the fourth blue light-emitting layer 7 can also be arranged on both sides of the first red light-emitting layer 4 respectively, and the second blue light-emitting layer 5 and the fourth blue light-emitting layer 7 serve as a common transport layer structure, which can improve the light-emitting intensity of red light.

[0031] Optionally, the second blue light-emitting layer 5 in the present application adopts a hole type host, which is prepared by using TCTA or mCP, and the thickness is 10-15 nm; the fourth blue light-emitting layer 7 adopts an electron type host, which is prepared by using CPB or Bepp2, and the thickness is 10-15 nm.

[0032] Further, as an optional embodiment of the present application, the light-emitting layer 1 is selected to be a green light-emitting layer, a red light-emitting layer or a yellow light-emitting layer according to the light-emitting efficiency of red and green light. When the green light-emitting layer is selected as the selected light-emitting layer 1, the host material is UGH3 (1,3-bis (triphenylsilyl) benzene), and 4CzIPN (2,4,5,6-tetrakis (carbazole-9-yl) -1,3-dicyanobenzene) or phosphorescence is doped, and the overall thickness is 20-30 nm; when the red light-emitting layer is selected as the selected light-emitting layer 1, the host material is TCTA, and the red phosphorescent material Ir(MDQ)2(acac) (bis (2-methyldibenzo (f, h) quinoxaline) acetylacetone iridium) is doped, and the overall thickness is 15-25 nm; when the yellow light-emitting layer is selected as the selected light-emitting layer 1, the phosphorescent material Ir(ppy)2(acac) (bis (2-phenylpyridine) acetylacetone iridium) is doped, and the overall thickness is 15-25 nm.

[0033] Further, as an optional embodiment of the present application, the first green light-emitting layer 2 and the first red light-emitting layer 4 in the present application are formed by FMM process, and the first green light-emitting layer 2 and the first red light-emitting layer 4 are formed by using the same design shape FMM template. The first green light-emitting layer 2 and the first red light-emitting layer 4 are formed by using the same design shape FMM template, which can avoid the problem of difficult mask process preparation caused by the overall pixel size of the light-emitting structure being too small, and improve the preparation precision of the first green light-emitting layer 2 and the first red light-emitting layer 4.

[0034] Optionally, as shown in Figure 6 the same design shape FMM template, the openings of the first green light-emitting layer 2 and the first red light-emitting layer 4 can be selectively arranged according to the needs, and the number of openings of the first green light-emitting layer 2 and the first red light-emitting layer 4 is adjusted according to the size of the FMM template. Optionally, when one FMM template contains four openings, the openings forming two red light-emitting layer units and two green light-emitting layer units can be arranged side by side or crosswise. Similarly, when one FMM template contains 8 openings, the openings forming four red light-emitting layer units and four green light-emitting layer units can be arranged side by side or crosswise.

[0035] Further, the present application also includes a display panel comprising a substrate, an anode layer and an organic light-emitting structure arranged in layers. The display panel with the organic light-emitting structure in the present application can omit the color film 11 structure in the blue light-emitting area, reduce the blue light loss caused by the color film 11 filtering, and improve the light-emitting intensity of blue light.

[0036] Further, as an optional embodiment of the present application, the anode layer in the present application comprises the first ITO layer 8, the second ITO layer 9 and the third ITO layer 10 arranged side by side; the projections of the first blue light emitting layer 3 and the second blue light emitting layer 5 on the substrate cover the first ITO layer 8, the second ITO layer 9 and the third ITO layer 10; the projections of the selection light emitting layer 1, the first green light emitting layer 2 and the first red light emitting layer 4 on the substrate cover the second ITO layer 9 and the third ITO layer 10. Specifically, the first ITO layer 8 corresponds to the blue light emitting region, the second ITO layer 9 corresponds to the green light emitting region, and the third ITO layer 10 corresponds to the red light emitting region. The second ITO layer 9 and the third ITO layer 10 are arranged adjacent to each other, and the thicknesses of the first ITO layer 8, the second ITO layer 9 and the third ITO layer 10 are different. The different thicknesses of the ITO layers can achieve specific wavelength light enhancement to cooperate with the blue, green and red light emitting.

[0037] Further, as an optional embodiment of the present application, the display panel further comprises a color film 11, and the projection of the color film 11 on the substrate is the same as the projection of the selection light emitting layer 1 on the substrate. Since the blue light emitting region is not blocked by the first red light emitting layer 4 and the first green light emitting layer 2, the blue light emitting does not need to be filtered through the color film 11. Therefore, the projection of the color film 11 on the substrate can be adjusted so that the color film 11 does not cover the blue light emitting region, thereby reducing the brightness loss of the blue light emitting caused by the color film 11.

[0038] Further, as an optional embodiment of the present application, the substrate is a silicon substrate, and the CMOS driving circuit is integrated on the silicon substrate, and the surface of the silicon substrate is subjected to planarization treatment.

[0039] Further, for the display panel in the present application, in addition to the substrate, the anode layer and the organic light emitting structure, other structure layers are further included.

[0040] Optionally, the anode layer further comprises a reflective anode layer, and the reflective anode layer is prepared by using a metal layer structure with high reflectivity. The reflective anode layer can form a mirror structure below each ITO layer to improve the light extraction efficiency. Optionally, the reflective anode layer is prepared by using silver-aluminum mixture, and the thickness of the reflective anode layer is 100-200 nm.

[0041] Correspondingly, the cathode layer 12 is arranged on the side of the third light emitting layer away from the anode layer, and the cathode layer 12 is prepared by using silver-magnesium mixture. Specifically, the silver-magnesium is proportioned at 9:1 and formed by evaporation. By controlling the proportion of silver-magnesium, a semi-transparent structure can be formed. The cathode layer 12 and the reflective anode layer cooperate to form a microcavity effect, and the red and green light can be emitted in a narrow spectrum through the microcavity resonance wavelength. At the same time, the semi-transparent cathode layer 12 can improve the top light output, thereby improving the light emitting efficiency of the display panel. Optionally, the thickness of the cathode layer 12 is 15-20 nm.

[0042] Further, as a preferred embodiment of the present application, the anode layer in the present application is sequentially stacked with a first hole injection layer 13 and a first hole transport layer 14 towards the side of the first light emitting layer. The first hole injection layer 13 is used to reduce the energy level difference between the anode layer and the first hole transport layer 14, so that the holes are more easily injected from the anode layer to the subsequent layer; the first hole transport layer 14 is used to receive the holes of the first hole injection layer 13 and transmit the holes to the first light emitting layer. Optionally, the first hole injection layer 13 is prepared by using HAT-CN (hexaazatriphenylenehexanitrile) or MoO3 (molybdenum trioxide); when prepared by using HAT-CN, the thickness of the first hole transport layer 14 is about 10 nm; when prepared by using MoO3, the thickness of the first hole transport layer 14 is about 5 nm. Optionally, the first hole transport layer 14 is prepared by using TAPC (1,1-bis[4-[N,N-di(p-tolyl)amino]phenyl]cyclohexane) or NPB (N,N'-di(1-naphthyl)-N,N'-diphenyl-1,1'-biphenyl-4,4'-diamine). When the first hole transport layer 14 is prepared by using TAPC, the thickness of the first hole transport layer 14 is 10-20 nm; when the first hole transport layer 14 is prepared by using NPB, the thickness of the first hole transport layer 14 is about 15 nm.

[0043] Further, as a preferred embodiment of the present application, the first light-emitting layer in the present application is sequentially stacked with a first electron transport layer 15, a first N-type charge generation layer 16, a first P-type charge generation layer 17 and a second hole transport layer 18 from the side of the second light-emitting layer. The first electron transport layer 15 is used to receive the un-combined electrons in the first light-emitting layer and transmit them to the first N-type charge generation layer 16, and to block the diffusion of holes in the first light-emitting layer to the second light-emitting layer; the first N-type charge generation layer 16 is used to provide electrons under an electric field and receive holes from the first P-type charge generation layer 17; the first P-type charge generation layer 17 is used to provide holes and inject the holes into the second hole transport layer 18; and the second hole transport layer 18 is used to receive the holes provided by the first P-type charge generation layer 17 and transmit the holes to the second light-emitting layer. Optionally, the first electron transport layer 15 is made of TPBi (1,3,5-tris(1-phenyl-1H-benzimidazol-2-yl)benzene) or TmPyPB (1,3,5-tris(6-phenylpyridine-2-yl)benzene), and when the first electron transport layer 15 is made of TPBi, the thickness is 20-30 nm; and when made of TmPyPB, the thickness is 25 nm. Optionally, the second hole transport layer 18 is made of TAPC (1,1-bis[4-[N,N-di(p-tolyl)amino]phenyl]cyclohexane) or NPB (N,N'-di(1-naphthyl)-N,N'-diphenyl-1,1'-biphenyl-4,4'-diamine), and when the second hole transport layer 18 is made of TAPC, the thickness is 10-20 nm; and when made of NPB, the thickness is about 15 nm.

[0044] Further, as a preferred embodiment of the present application, the second light-emitting layer is sequentially stacked with a second electron transport layer 19, a second N-type charge generation layer 20, a second P-type charge generation layer 21 and a third hole transport layer 22 from the side of the third light-emitting layer. The second electron transport layer 19 functions similarly to the first electron transport layer 15, receiving the un-combined electrons in the second light-emitting layer, transporting them to the second N-type charge generation layer 20, and blocking the diffusion of holes in the second light-emitting layer to the third light-emitting layer; the second N-type charge generation layer 20 is used to provide electrons under an electric field, and receive the holes of the second P-type charge generation layer 21; the second P-type charge generation layer 21 is used to provide holes, and inject the holes into the third light-emitting layer; the third hole transport layer 22 is used to receive the holes of the second P-type charge generation layer 21, and transport the holes to the third light-emitting layer. Optionally, the second electron transport layer 19 is made of TPBi (1,3,5-tris(1-phenyl-1H-benzimidazol-2-yl)benzene) or TmPyPB (1,3,5-tris(6-phenylpyridine-2-yl)benzene); when the second electron transport layer 19 is made of TPBi, the thickness is 20-30 nm; when made of TmPyPB, the thickness is 25 nm. Optionally, the third hole transport layer 22 is made of TAPC (1,1-bis[4-[N,N-di(p-tolyl)amino]phenyl]cyclohexane) or NPB (N,N'-di(1-naphthyl)-N,N'-diphenyl-1,1'-biphenyl-4,4'-diamine); when the third hole transport layer 22 is made of TAPC, the thickness is 10-20 nm; when made of NPB, the thickness is about 15 nm.

[0045] Further, as a preferred embodiment of the present application, the third light-emitting layer is sequentially stacked with a third electron transport layer 23 and a first electron injection layer 24 from the side of the cathode layer 12. The third electron transport layer 23 is used to receive the electrons of the first electron injection layer 24, and transport the electrons to the third light-emitting layer, so that the electrons and holes are combined in the third light-emitting layer; the first electron injection layer 24 is used to lower the potential barrier between the cathode layer 12 and the third electron transport layer 23, so that the electrons are detached from the cathode and injected into the third electron transport layer 23. Optionally, the third electron transport layer 23 is made of TPBi (1,3,5-tris(1-phenyl-1H-benzimidazol-2-yl)benzene) or TmPyPB (1,3,5-tris(6-phenylpyridine-2-yl)benzene); when the third electron transport layer 23 is made of TPBi, the thickness is 20-30 nm; when made of TmPyPB, the thickness is about 25 nm. Optionally, the first electron injection layer 24 is made of LiF (lithium fluoride) or Yb (ytterbium), and the thickness of the first electron injection layer 24 is about 1 nm.

[0046] Further, as an optional embodiment of the present application, the first green light emitting layer 2 and the first red light emitting layer 4 in the present application are formed by FMM process, and the first green light emitting layer 2 and the first red light emitting layer 4 are formed by using the FMM template with the same design shape.

[0047] Optionally, the side of the cathode layer 12 away from the substrate is further sequentially provided with a light extraction layer 25 and an encapsulation layer. The light extraction layer 25 is used to improve light utilization and reduce light loss; the encapsulation layer is used to isolate external water and oxygen, thereby prolonging the service life of the display panel. The light extraction layer 25 is prepared by evaporation of CPL or deposition of IZO (indium zinc oxide). The encapsulation layer is prepared by a laminated thin film structure of SiN3 / SiOx and TiO / Al2O3.

[0048] Optionally, the first blue light emitting layer 3, the second blue light emitting layer 5, the third blue light emitting layer 6 and the fourth blue light emitting layer 7 in the present application are prepared by TCTA (4,4',4''-tris (carbazol-9-yl) triphenylamine) or mCP (1,3-bis (carbazol-9-yl) benzene).

[0049] Further, for the display panel in the present application, the present application further includes a preparation method of the display panel, which includes the following steps: selecting a substrate; forming a first light emitting layer, a second light emitting layer and a third light emitting layer on the substrate in sequence; The first light emitting layer is a selection light emitting layer 1, and the selection light emitting layer 1 is one of a red light emitting layer, a green light emitting layer or a yellow light emitting layer; The second light emitting layer is a first green light emitting layer 2 and a first blue light emitting layer 3 arranged in layers, and the projection of the first green light emitting layer 2 on the substrate falls into the projection of the first blue light emitting layer 3 on the substrate; The third light emitting layer is a first red light emitting layer 4 and a second blue light emitting layer 5 arranged in layers, and the projection of the first red light emitting layer 4 on the substrate falls into the projection of the second blue light emitting layer 5 on the substrate.

[0050] Optionally, the forming order of the first green light emitting layer 2 and the first blue light emitting layer 3 in the second light emitting layer in the present application is not limited, and the first green light emitting layer 2 or the first blue light emitting layer 3 can be formed first.

[0051] Optionally, the forming order of the first red light emitting layer 4 and the second blue light emitting layer 5 in the second light emitting layer in the present application is not limited, and the first red light emitting layer 4 or the second blue light emitting layer 5 can be formed first.

[0052] Further, as an optional embodiment of the present application, in the second light emitting layer, a third blue light emitting layer 6 can also be formed on the side of the first green light emitting layer 2 away from the first blue light emitting layer 3.

[0053] Further, as an optional embodiment of the present application, a fourth blue light emitting layer 7 can also be formed on the side of the first red light emitting layer 4 away from the second blue light emitting layer 5.

[0054] Further, as an optional embodiment of the present application, an anode layer can also be formed between the substrate and the first light emitting layer, and a cathode layer 12 can also be formed on the side of the third light emitting layer away from the substrate. The thickness of the indium tin oxide layer in the anode layer is adjusted according to the requirements of different color pixels to form the first, second and third indium tin oxide layers 8, 9 and 10.

[0055] Further, as an optional embodiment of the present application, a first hole injection layer 13 and a first hole transport layer 14 can be formed in sequence on the side of the anode layer facing the first light emitting layer; a first electron transport layer 15, a first N-type charge generation layer 16, a first P-type charge generation layer 17 and a second hole transport layer 18 can be formed in sequence on the side of the first light emitting layer facing the second light emitting layer; a second electron transport layer 19, a second N-type charge generation layer 20, a second P-type charge generation layer 21 and a third hole transport layer 22 can be formed in sequence on the side of the second light emitting layer facing the third light emitting layer; a third electron transport layer 23 and a first electron injection layer 24 can be formed in sequence on the side of the third light emitting layer facing the cathode layer 12; a light extraction layer 25 and an encapsulation layer can also be formed on the side of the cathode layer 12 away from the substrate; and finally, a color film 11 can be formed on the side of the encapsulation layer away from the substrate.

[0056] The display panel in the present application can improve the red and green light emitting efficiency by more than 80%, reduce the brightness loss of blue light caused by the color film 11 by more than 30%, and reduce the current density by the double blue light emitting layer structure, thereby improving the service life of blue light by more than 50%.

[0057] Further, for the display panel in the present application, the present application also includes a display device comprising the above display panel. By using the above display panel, the light emitting brightness of red, green and blue light in the display device can be significantly improved, and the overall brightness can reach more than 12000 nits.

[0058] Those skilled in the art will readily understand that the above description is only the preferred embodiment of the present application, and is not intended to limit the present application. Any modification, equivalent replacement and improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. An organic light-emitting structure, characterized in that, include: The first light-emitting layer, the second light-emitting layer, and the third light-emitting layer are stacked sequentially. The first light-emitting layer includes a selective light-emitting layer, which is one of a red light-emitting layer, a green light-emitting layer, or a yellow light-emitting layer; The second light-emitting layer includes a first green light-emitting layer and a first blue light-emitting layer stacked together; the projection of the first green light-emitting layer on the substrate falls into the projection of the first blue light-emitting layer on the substrate; The third light-emitting layer includes a first red light-emitting layer and a second blue light-emitting layer stacked together; the projection of the first red light-emitting layer on the substrate falls into the projection of the second blue light-emitting layer on the substrate.

2. The organic light-emitting structure according to claim 1, characterized in that, The first green light emitting layer is disposed on the side of the first blue light emitting layer close to the first light emitting layer.

3. The organic light-emitting structure according to claim 1, characterized in that, The first green light emitting layer is disposed on the side of the first blue light emitting layer away from the first light emitting layer.

4. The organic light-emitting structure according to claim 2 or 3, characterized in that, The second light-emitting layer further includes a third blue light-emitting layer; the third blue light-emitting layer is disposed on the side of the first green light-emitting layer away from the first blue light-emitting layer, and the projection of the third blue light-emitting layer on the substrate is the same as the projection of the first blue light-emitting layer on the substrate.

5. The organic light-emitting structure according to claim 1, characterized in that, The first red light emitting layer is disposed on the side of the second blue light emitting layer close to the first light emitting layer.

6. The organic light-emitting structure according to claim 1, characterized in that, The first red light emitting layer is disposed on the side of the second blue light emitting layer away from the first light emitting layer.

7. The organic light-emitting structure according to claim 5 or 6, characterized in that, The third light-emitting layer further includes a fourth blue light-emitting layer; the fourth blue light-emitting layer is disposed on the side of the first red light-emitting layer away from the second blue light-emitting layer, and the projection of the fourth blue light-emitting layer on the substrate is the same as the projection of the second blue light-emitting layer on the substrate.

8. A display panel, characterized in that, It includes a substrate, an anode layer, and an organic light-emitting structure as described in any one of claims 1 to 7, all of which are stacked together.

9. The display panel according to claim 8, characterized in that, The anode layer includes a first indium tin oxide layer, a second indium tin oxide layer, and a third indium tin oxide layer arranged in parallel. The projections of the first blue light emitting layer and the second blue light emitting layer along the substrate direction cover the first indium tin oxide layer, the second indium tin oxide layer, and the third indium tin oxide layer; The projection of the selected light-emitting layer, the first green light-emitting layer, and the first red light-emitting layer along the substrate direction covers the second indium tin oxide layer and the third indium tin oxide layer.

10. The display panel according to claim 8 or 9, characterized in that, It also includes a color filter, the projection of which on the substrate is the same as the projection of the selective light-emitting layer on the substrate.

11. A display device, characterized in that, Includes the display panel as described in any one of claims 8 to 10.

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