WO2020119556A1

WO2020119556A1 - Light-emitting device and display device

Info

Publication number: WO2020119556A1
Application number: PCT/CN2019/123074
Authority: WO
Inventors: 刘振; 卓恩宗
Original assignee: 惠科股份有限公司
Priority date: 2018-12-12
Filing date: 2019-12-04
Publication date: 2020-06-18
Also published as: CN109560208A

Abstract

A light-emitting device (100) and a display device (200), wherein the light-emitting device (100) comprises a cathode metal layer (10A), an anode metal layer (10B), a charge generation layer (70), a red and green light-emitting composite layer (40) and a quantum dot blue light-emitting layer (80); the charge generation layer (70) is arranged between the cathode metal layer (10A) and the anode metal layer (10B); the red and green light-emitting composite layer (40) is arranged between the cathode metal layer (10A) and the charge generation layer (70); and the quantum dot blue light-emitting layer (80) is arranged between the charge generation layer (70) and the anode metal layer (10B).

Description

Light emitting device and display device The

Related application

This application requires the priority of the Chinese patent application with the application number 201811523220.7 and the name "Light-emitting device and display device", which was applied on December 12, 2018, and the entire content is hereby incorporated by reference.

Technical field

The present application relates to the field of display technology, in particular to a light-emitting device and a display device.

Background technique

OLED (Organic Light-Emitting Diode (Organic Light Emitting Diode) display device, because the blue light emission frequency is higher than that of red light and green light, and the photon energy of blue light is higher, resulting in the decay or aging of the blue organic material, shortening the life of the OLED display device.

The statements here only provide background information related to this application and do not necessarily constitute prior art

Summary of the invention

The main purpose of the present application is to provide a light-emitting device and a display device, which can improve the monochromatic purity of the display device, widen the display color gamut of the display device, and increase the life of the display device, especially to achieve a significant increase in the use of large-size OLED display devices life.

In order to achieve the above object, a light emitting device proposed by the present application, the light emitting device includes:

A cathode metal layer, the cathode metal layer is electrically connected to an external power supply cathode;

An anode metal layer, the anode metal layer is electrically connected to an external power supply anode;

A charge generation layer, the charge generation layer is disposed between the cathode metal layer and the anode metal layer;

A red-green light-emitting composite layer provided between the cathode metal layer and the charge generation layer; and

A quantum dot blue light emitting layer is provided between the charge generation layer and the anode metal layer.

Optionally, the red-green light-emitting composite layer is an organic electroluminescent material layer.

Optionally, the red-green light-emitting composite layer includes an adjacent red light-emitting layer and a green light-emitting layer, wherein the green light-emitting layer is disposed between the cathode metal layer and the red light-emitting layer .

Optionally, the red-green light-emitting composite layer includes an adjacent red light-emitting layer and a green light-emitting layer, wherein the red light-emitting layer is disposed between the cathode metal layer and the green light-emitting layer .

Optionally, the red-green light-emitting composite layer is composed of red and green light-emitting organic electroluminescent materials doped with each other.

Optionally, an adjacent first electron injection layer and a first electron transport layer are further provided between the red-green light-emitting composite layer and the cathode metal layer, wherein the first electron injection layer and the The cathode metal layer is connected, and the first electron transport layer is connected to the red-green light-emitting composite layer.

Optionally, a first hole injection layer and a first hole transport layer are provided adjacent to each other between the red-green light-emitting composite layer and the charge generation layer, wherein the first hole injection layer Connected to the charge generation layer, the first hole transport layer is connected to the red-green light-emitting composite layer.

Optionally, an adjacent second electron injection layer and a second electron transport layer are also provided between the charge generation layer and the quantum dot blue light emitting layer, wherein the second electron injection layer and the The charge generation layer is connected, and the second electron transport layer is connected to the quantum dot blue light emitting layer.

Optionally, a second hole injection layer and a second hole transport layer adjacent to each other are provided between the quantum dot blue light-emitting layer and the anode metal layer, wherein the second hole injection layer Connected to the anode metal layer, the second hole transport layer is connected to the quantum dot blue light emitting layer.

Optionally, the quantum dots in the blue light emitting layer of quantum dots are spherical semiconductor nanoparticles composed of group II-VI or III-V elements.

Optionally, the red-green light-emitting composite layer is a quantum dot light-emitting layer.

Optionally, the light-emitting device further includes a substrate, the cathode metal layer, a quantum dot blue light-emitting layer, a charge generation layer, a red-green light-emitting composite layer, an anode metal layer, and the substrate are sequentially stacked.

To achieve the above object, the present application also provides a light-emitting device, the light-emitting device includes a substrate and a cathode metal layer, a first electron injection layer, a first electron transport layer stacked on the substrate in order from top to bottom, Red-green light-emitting composite layer, first hole transport layer, first hole injection layer, charge generation layer, second electron injection layer, second electron transport layer, quantum dot blue light emitting layer, second hole transport layer, first Two hole injection layer and anode metal layer.

Optionally, the red-green light-emitting composite layer is an organic electroluminescent material layer or a quantum dot light-emitting layer.

Optionally, the red-green light-emitting composite layer includes an adjacent red light-emitting layer and a green light-emitting layer, wherein the green light-emitting layer is disposed between the cathode metal layer and the red light-emitting layer Or, the red light emitting layer is disposed between the cathode metal layer and the green light emitting layer.

To achieve the above object, the present application also provides a display device including a light emitting device, the light emitting device including: a cathode metal layer, the cathode metal layer is electrically connected to an external power supply cathode;

Optionally, the display device further includes an array substrate and a color filter substrate, at least one of the light emitting devices is disposed between the array substrate and the color filter substrate, and is formed between the array substrate and the color filter substrate A white light area.

Optionally, the array substrate is provided with a plurality of thin film transistor units arranged in an array and arranged to drive the light emitting devices to emit white light, and the thin film transistor units correspond to the light emitting devices in one-to-one correspondence.

Optionally, the color filter substrate is provided with a plurality of color resisting units arranged in an array, and the color resisting units correspond to the light emitting devices in one-to-one correspondence.

In the light-emitting device and the display device provided with the light-emitting device proposed in this application, the quantum dot material in the quantum dot blue light-emitting layer due to the existence of quantum confinement effect, the original continuous energy band changes into a discrete energy level structure, when When stimulated by light or electricity, quantum dots will emit colored light. The color of light is related to its nature. Therefore, blue light can be generated by controlling the light emitted by changing its size. The quantum dot blue light-emitting layer has the advantages of concentrated emission spectrum and high color purity, which can greatly increase the color gamut of the display device and enhance the color reduction ability of the display device. At the same time, the quantum dot material in the quantum dot blue light emitting layer will not cause aging or decay problems like the blue organic electroluminescent material, thereby effectively improving the life span and stability of the display device, especially the large-size display device.

BRIEF DESCRIPTION

In order to more clearly explain the technical solutions in the embodiments or exemplary technologies of the present application, the drawings required for the description of the embodiments or exemplary technologies will be briefly described below. Obviously, the drawings in the following description are only These are some embodiments of the present application. For those of ordinary skill in the art, without paying any creative work, other drawings can be obtained according to the structures shown in these drawings.

1 is a schematic structural diagram of an embodiment of a light-emitting device of the present application;

2 is a schematic structural diagram 1 of another embodiment of a light-emitting device of the present application;

FIG. 3 is a schematic structural diagram 2 of another embodiment of a light-emitting device of this application;

4 is a schematic structural diagram of an embodiment of a display device according to this application.

The implementation, functional characteristics and advantages of the present application will be further described in conjunction with the embodiments and with reference to the drawings.

detailed description

The technical solutions in the embodiments of the present application will be described clearly and completely with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative work fall within the protection scope of the present application.

It should be noted that all directional indicators (such as up, down, left, right, front, back, etc.) in the embodiments of the present application are only set to explain the inter-components in a certain posture (as shown in the drawings) With respect to the relative positional relationship, movement conditions, etc., if the specific posture changes, the directional indication changes accordingly.

In addition, the descriptions related to "first", "second", etc. in this application are only set for descriptive purposes, and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of indicated technical features. Thus, the features defined with "first" and "second" may include at least one of the features either explicitly or implicitly. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary people in the art to achieve, when the combination of technical solutions conflicts with each other or cannot be realized, it should be considered that the combination of such technical solutions does not exist , Nor within the scope of protection required by this application.

Referring to FIG. 1, a light-emitting device 100 proposed by the present application includes: a cathode metal layer 10A, the cathode metal layer 10A is electrically connected to an external power supply cathode; an anode metal layer 10B, the anode metal layer 10B is electrically connected to the external power supply anode; the charge generation layer 70 (charge generate layer, CGL), the charge generation layer 70 is disposed between the cathode metal layer 10A and the anode metal layer 10B; a red-green light-emitting composite layer 40, the red-green light-emitting composite layer 40 is disposed between the cathode metal layer 10A and the Between the charge generation layer 70; a quantum dot blue light emitting layer 80, the quantum dot blue light emitting layer 80 is disposed between the charge generation layer 70 and the anode metal layer 10B.

In this embodiment, after the cathode metal layer 10A is connected to an external power cathode and the anode metal layer 10B is connected to an external power anode, electrons in the cathode metal layer 10A flow to the red-green light-emitting composite layer 40, At the same time, the holes in the charge generation layer 70 flow to the red-green light-emitting composite layer 40, and electrons and holes meet and excite in the red-green light-emitting composite layer 40 to emit red light and green light; at the same time, the charge generation The electrons in the layer 70 flow to the quantum dot blue light-emitting layer 80, the holes of the anode metal layer 10B flow to the quantum dot blue light-emitting layer 80, and the electrons and holes flow in the quantum dot blue light-emitting layer 80 due to convection. A current is generated, and the luminescent material in the quantum dot blue light emitting layer 80 is excited by the current to emit blue light; the red and green light emitted by the red-green light emitting composite layer 40 is mixed with the blue light emitted by the quantum dot blue light emitting layer 80 After forming white light, the white light emitted by the light emitting device 100 can be used as a backlight of a display device.

In this embodiment, it needs to be pointed out that the light emitting material of the quantum dot blue light emitting layer 80 is a quantum dot (Quantum Dots, QDs) materials, quantum dots are usually spherical semiconductor nanoparticles composed of II-VI or III-V group elements, and the particle size is generally between a few nanometers and tens of nanometers. Due to the existence of quantum confinement effect, the original continuous energy band of quantum dot materials changes into a discrete energy level structure. When stimulated by light or electricity, quantum dots will emit colored light, so you can change the size or material of quantum dots. Control the light emitted by it to produce blue light. The quantum dot blue light-emitting layer 80 has the advantages of concentrated emission spectrum and high color purity, which can greatly improve the color gamut of the display device and enhance the color reduction ability of the display device. At the same time, the quantum dot material in the quantum dot blue light emitting layer 80 will not be like a blue organic electroluminescent material (Organic Light-Emitting Diode (OLED) also causes aging or decay problems, thereby effectively improving the life and stability of display devices, especially large-size display devices.

Optionally, a first electron injection layer 20A and a first electron transport layer 30A adjacent to each other are provided between the red-green light-emitting composite layer 40 and the cathode metal layer 10A, wherein the first electron injection The layer 20A is connected to the cathode metal layer 10A, and the first electron transport layer 30A is connected to the red-green light-emitting composite layer 40.

In this embodiment, the electrons in the cathode metal layer 10A sequentially enter the red-green light-emitting composite layer 40 through the first electron injection layer 20A and the first electron transport layer 30A, and recombine with the red-green light-emitting composite The holes in the layer 40 meet and excite green and red light.

Optionally, a first hole injection layer 60A and a first hole transport layer 50A adjacent to each other are provided between the red-green light-emitting composite layer 40 and the charge generation layer 70, wherein the first empty The hole injection layer 60A is in contact with the charge generation layer 70, and the first hole transport layer 50A is in contact with the red-green light-emitting composite layer 40.

In this embodiment, the holes in the charge generation layer 70 enter the red-green light-emitting composite layer 40 through the first hole injection layer 60A and the first hole transport layer 50A, and the red The electrons in the green light-emitting composite layer 40 meet and excite green light and red light.

Optionally, a second electron injection layer 20B and a second electron transport layer 30B are provided adjacent to each other between the charge generation layer 70 and the quantum dot blue light-emitting layer 80, wherein the second electron injection layer 20B is in contact with the charge generation layer 70, and the second electron transport layer 30B is in contact with the quantum dot blue light-emitting layer 80.

In this embodiment, the electrons in the charge generation layer 70 enter the quantum dot blue light emitting layer 80 through the second electron injection layer 20B and the second electron transport layer 30B in sequence, and emit blue light with the quantum dot The holes in layer 80 meet and excite blue light.

Optionally, a second hole injection layer 60B and a second hole transport layer 50B adjacent to each other are provided between the quantum dot blue light emitting layer 80 and the anode metal layer 10B, wherein the second void The hole injection layer 60B is connected to the anode metal layer 10B, and the second hole transport layer 50B is connected to the quantum dot blue light-emitting layer 80.

In this embodiment, holes in the anode metal layer 10B enter the quantum dot blue light-emitting layer 80 through the second hole injection layer 60B and the second hole transport layer 50B in sequence with the quantum The electrons of the blue light-emitting layer 80 meet and excite blue light.

Optionally, the red-green light-emitting composite layer 40 is an organic electroluminescent material layer.

In this embodiment, since the red and green photon energy emitted by the organic electroluminescent material in the red-green light-emitting composite layer 40 is not as high as the blue photon energy, there is no problem of premature decay or aging. Therefore, The red-green light-emitting composite layer 40 may be an organic light-emitting unit. It can be understood that the red-green light-emitting composite layer 40 may also be a quantum dot light-emitting layer.

Please refer to FIG. 1. Optionally, the red-green light-emitting composite layer 40 includes a green light-emitting layer 41 and a red light-emitting layer 42 that are adjacently arranged, wherein the green light-emitting layer 41 is disposed on the cathode metal layer 10A and the red light emitting layer 42.

In this embodiment, the green light-emitting layer 41 in the red-green light-emitting composite layer 40 is disposed between the cathode metal layer 10A and the red light-emitting layer 42, that is, the green light-emitting layer 41 is more Close to the cathode metal layer 10A, when the energy level of the organic light emitting material in the green light emitting layer 41 is closer to the first electron transport layer than the energy level of the organic light emitting material in the red light emitting layer 42 When the energy level of the material in 30A, the green light-emitting layer 41 is placed closer to the cathode metal layer 10A to be in contact with the first electron transport layer 30A, which is more conducive to the first electron transport layer 30A The electrons are transmitted to the red-green light-emitting composite layer 40.

Please refer to FIG. 2. Optionally, the red-green light-emitting composite layer 40 includes an adjacent red light-emitting layer 42 and a green light-emitting layer 41, wherein the red light-emitting layer 42 is disposed on the cathode metal layer 10A With the green light-emitting layer 41.

In this embodiment, the red light-emitting layer 42 in the red-green light-emitting composite layer 40 is disposed between the cathode metal layer 10A and the green light-emitting layer 41, that is, the red light-emitting layer 42 is more Close to the cathode metal layer 10A, when the energy level of the organic light emitting material in the red light emitting layer 42 is closer to the first electron transport layer than the energy level of the organic light emitting material in the green light emitting layer 41 When the energy level of the material in 30A, the red light-emitting layer 42 is disposed closer to the cathode metal layer 10A to be in contact with the first electron transport layer 30A, which is more conducive to the first electron transport layer 30A The electrons are transmitted to the red-green light-emitting composite layer 40.

Please refer to FIG. 3. Optionally, the red-green light-emitting composite layer 40 is formed by doping organic electroluminescent materials emitting red light and green light.

In this embodiment, when the energy levels of the red light emitting material and the green light emitting material in the red-green light emitting composite layer 40 are similar to the energy levels of the materials in the first electron transport layer 30A, the red The red and green light-emitting composite layer 40 is doped with light and green light-emitting organic electroluminescent materials, and at this time, the red-green light-emitting composite layer 40 is formed at one time without forming the red light-emitting layer 42 and the red light-emitting layer 42 separately. The green light-emitting layer 41 simplifies the production process and saves production costs.

In other embodiments, the light-emitting device 100 further includes a substrate 90, the cathode metal layer 10A, the first electron injection layer 20A, the first electron transport layer 30A, the red-green light-emitting composite layer 40, the first hole transport Layer 50A, first hole injection layer 60A, charge generation layer 70, second electron injection layer 20B, second electron transport layer 30B, quantum dot blue light emitting layer 80, second hole transport layer 50B, second hole injection The layer 60B and the anode metal layer 10B are sequentially stacked on the substrate 90 from top to bottom.

In addition, referring to FIG. 4, the present application also proposes a display device 200 including the above-mentioned light-emitting device 100, an array substrate 201 and a color filter substrate 202, at least one of the light-emitting devices 100 is disposed in the array Between the substrate 201 and the color filter substrate 202, the light emitting device 100 forms a white light emitting region 205 between the array substrate 201 and the color filter substrate 202, and the color filter substrate 202 is disposed in the white light region 205 to emit light side.

In this embodiment, the array substrate 201 is provided with a plurality of thin film transistor units 203 arranged in an array arranged to drive the light emitting device 100 to emit light. The thin film transistor units 203 correspond to the light emitting device 100 in one-to-one correspondence. The thin film transistor unit 203 adjusts the light emitting brightness of the light emitting devices 100, and each of the light emitting devices 100 corresponds to a color resisting unit 204 provided in an array on the color film substrate 202, wherein one red resisting unit 204A, one The green resistance unit 204B and the blue resistance unit 204C form a pixel unit, and the white light emitted by the light-emitting device 100 passes through a plurality of pixel units on the color filter substrate 202 to form a display screen.

In this embodiment, since the display device 200 includes the above-mentioned light-emitting device 100, it has at least the above-mentioned technical effects of the above-mentioned light-emitting device 100, which will not be repeated here. In addition, the display device 200 further includes a housing, a main control circuit, and the like.

The above is only an optional embodiment of the present application, and does not limit the patent scope of the present application. Any equivalent structural transformation made by the description and drawings of the present application under the concept of the application of the present application, or direct/indirect Applications in other related technical fields are included in the scope of patent protection of this application.

Claims

A light emitting device, wherein the light emitting device includes:

A cathode metal layer, the cathode metal layer is electrically connected to an external power supply cathode;

An anode metal layer, the anode metal layer is electrically connected to an external power supply anode;

A charge generation layer, the charge generation layer is disposed between the cathode metal layer and the anode metal layer;

A red-green light-emitting composite layer provided between the cathode metal layer and the charge generation layer; and

A quantum dot blue light emitting layer is provided between the charge generation layer and the anode metal layer.
The light-emitting device according to claim 1, wherein the red-green light-emitting composite layer is an organic electroluminescent material layer.
The light-emitting device according to claim 2, wherein the red-green light-emitting composite layer includes a red light-emitting layer and a green light-emitting layer provided adjacently, wherein the green light-emitting layer is provided on the cathode metal layer and Between the red light emitting layers.
The light-emitting device according to claim 2, wherein the red-green light-emitting composite layer includes a red light-emitting layer and a green light-emitting layer provided adjacently, wherein the red light-emitting layer is provided on the cathode metal layer and Between the green light emitting layers.
The light-emitting device according to claim 2, wherein the red-green light-emitting composite layer is composed of organic light-emitting materials that emit red light and green light and are doped with each other.
The light-emitting device according to claim 1, wherein a first electron injection layer and a first electron transport layer which are adjacently arranged are further provided between the red-green light-emitting composite layer and the cathode metal layer, wherein the The first electron injection layer is connected to the cathode metal layer, and the first electron transport layer is connected to the red-green light-emitting composite layer.
The light-emitting device according to claim 6, wherein a first hole injection layer and a first hole transport layer are provided adjacently between the red-green light-emitting composite layer and the charge generation layer, wherein, The first hole injection layer is connected to the charge generation layer, and the first hole transport layer is connected to the red-green light-emitting composite layer.
The light-emitting device according to claim 7, wherein a second electron injection layer and a second electron transport layer are provided adjacent to each other between the charge generation layer and the quantum dot blue light-emitting layer, wherein the The second electron injection layer is in contact with the charge generation layer, and the second electron transport layer is in contact with the quantum dot blue light-emitting layer.
The light emitting device according to claim 8, wherein a second hole injection layer and a second hole transport layer which are adjacently arranged are further provided between the quantum dot blue light emitting layer and the anode metal layer, wherein, The second hole injection layer is connected to the anode metal layer, and the second hole transport layer is connected to the quantum dot blue light-emitting layer.
The light emitting device according to claim 1, wherein the quantum dots in the quantum dot blue light emitting layer are spherical semiconductor nanoparticles composed of group II-VI or group III-V elements.
The light emitting device according to claim 1, wherein the red-green light-emitting composite layer is a quantum dot light-emitting layer.
The light emitting device according to claim 1, wherein the light emitting device further comprises a substrate, the cathode metal layer, a quantum dot blue light emitting layer, a charge generating layer, a red-green light emitting composite layer, an anode metal layer and the substrate Order overlapping.
A light-emitting device, wherein the light-emitting device includes a substrate and a cathode metal layer, a first electron injection layer, a first electron transport layer, a red-green light-emitting composite layer, a A hole transport layer, a first hole injection layer, a charge generation layer, a second electron injection layer, a second electron transport layer, a quantum dot blue light emitting layer, a second hole transport layer, a second hole injection layer and an anode Metal layer.
The light-emitting device according to claim 13, wherein the red-green light-emitting composite layer is an organic electroluminescent material layer or a quantum dot light-emitting layer.
The light-emitting device according to claim 13, wherein the red-green light-emitting composite layer includes an adjacent red light-emitting layer and a green light-emitting layer, wherein the green light-emitting layer is provided on the cathode metal layer and Between the red light emitting layers, or the red light emitting layer is disposed between the cathode metal layer and the green light emitting layer.
The light-emitting device according to claim 13, wherein the red-green light-emitting composite layer is formed by doping organic electroluminescent materials emitting red light and green light.
A display device, wherein the display device includes a light emitting device, and the light emitting device includes:

A cathode metal layer, the cathode metal layer is electrically connected to an external power supply cathode;

An anode metal layer, the anode metal layer is electrically connected to an external power supply anode;

A charge generation layer, the charge generation layer is disposed between the cathode metal layer and the anode metal layer;

A red-green light-emitting composite layer provided between the cathode metal layer and the charge generation layer; and

A quantum dot blue light emitting layer is provided between the charge generation layer and the anode metal layer.
The display device according to claim 17, wherein the display device further comprises an array substrate and a color filter substrate, at least one of the light emitting devices is disposed between the array substrate and the color filter substrate, and is located in the array A white light emitting area is formed between the substrate and the color filter substrate.
The display device according to claim 18, wherein the array substrate is provided with a plurality of thin film transistor units arranged in an array and arranged to drive the light emitting devices to emit white light, and the thin film transistor units correspond to the light emitting devices in one-to-one correspondence .
The display device according to claim 18, wherein the color filter substrate is provided with a plurality of color resist units arranged in an array, and the color resist units correspond to the light emitting devices in one-to-one correspondence. The