CN113241414A

CN113241414A - Light emitting device, display apparatus, and method of manufacturing light emitting device

Info

Publication number: CN113241414A
Application number: CN202110434747.8A
Authority: CN
Inventors: 陈树明; 陈练娜; 张恒
Original assignee: Southwest University of Science and Technology
Current assignee: Southwest University of Science and Technology; Southern University of Science and Technology
Priority date: 2021-04-22
Filing date: 2021-04-22
Publication date: 2021-08-10

Abstract

The application relates to a light emitting device, a display device and a manufacturing method of the light emitting device. The light emitting layer generates mixed light beams of a first primary color, a second primary color and a third primary color, each sub-electrode in the first electrode works independently, and each light-transmitting phase adjusting layer adjusts the resonant wavelength of a resonant cavity between the first electrode and the second electrode into the wavelength of light of different primary colors so as to convert the mixed light beams into light of different primary colors. Energy between the quantum dots of each primary color is different, energy transfer can be carried out, energy supplement and promotion can be carried out mutually during light emitting, the resonant cavity between the first electrode and the second electrode accelerates the radiative recombination of excitons of resonant light, namely, the light efficiency of each quantum dot is enhanced, the technical problem that the full-color display effect of the existing quantum dot light-emitting diode is not ideal in the prior art is solved, and the technical effect of improving the full-color display of the quantum dot light-emitting diode is achieved.

Description

Light emitting device, display apparatus, and method of manufacturing light emitting device

Technical Field

The present disclosure relates to the field of display technologies, and in particular, to a light emitting device, a display apparatus, and a method for manufacturing the light emitting device.

Background

Quantum Dot Light-Emitting Diodes (QLEDs) have become a new trend in the display field due to their unique advantages of high color purity, adjustable Light emission color, good stability, solution processibility, etc. In order to realize the full-color display of the quantum dot light-emitting diode, the quantum dot light-emitting layer must be patterned to form a red, green and blue QLED pixel array which is arranged side by side in parallel. Since quantum dots can only be deposited by a solution process, a series of technical challenges still exist in the solution patterning process, and the application of the QLED in full-color display is limited. The currently proposed methods for imaging quantum dot pixels mainly include three methods: the first mode is ink-jet printing, namely, quantum dots are prepared into ink, the ink is sprayed out by an ink-jet printer, and a quantum dot film with a preset pattern is deposited on a substrate, but the precision of the ink-jet printing is low, so that the resolution of the formed quantum dot film is low; the second mode is transfer printing, namely, a silicon wafer is made into a concave-convex imaging stamp, and quantum dots are transferred onto a film substrate by utilizing the adsorption force between the stamp and the quantum dots, but the transfer printing process is complex and is difficult to prepare in a large area; the third method is photolithography, i.e. mixing quantum dots with a ligand cross-linking agent and spin-coating to form a film, so that the quantum dots are cross-linked under the irradiation of ultraviolet light, thereby forming a stable film, and the unexposed part is washed away by a solvent, thereby finally forming a quantum dot pattern on the substrate, but the introduction of chemical additives such as the cross-linking agent can cause the performance of the quantum dots to be reduced.

Therefore, the full-color display effect of the present quantum dot light-emitting diode is not ideal.

Disclosure of Invention

In view of the above, it is necessary to provide a light emitting device, a display apparatus, and a method for manufacturing the light emitting device, in order to solve the problem that the full-color display effect of the present quantum dot light emitting diode is not ideal.

In a first aspect, there is provided a light emitting device comprising:

the first electrode comprises a first sub-electrode, a second sub-electrode and a third sub-electrode which are mutually independent;

the luminescent layer at least comprises a quantum dot luminescent layer which is made by mixing quantum dots of a first primary color, quantum dots of a second primary color and quantum dots of a third primary color, and the quantum dot luminescent layer is used for producing a mixed light beam comprising the first primary color, the second primary color and the third primary color;

a light-transmitting phase adjustment layer disposed between the first electrode and the light-emitting layer, the light-transmitting phase adjustment layer including:

the first light-transmitting phase adjusting layer is arranged between the first sub-electrode and the light-emitting layer and is used for adjusting the resonant wavelength of a resonant cavity between the first sub-electrode and the second electrode to the wavelength of light of a first primary color so as to generate the light of the first primary color;

the second light-transmitting phase adjusting layer is arranged between the second sub-electrode and the light-emitting layer and is used for adjusting the resonant wavelength of the resonant cavity between the second sub-electrode and the second electrode to the wavelength of light of a second primary color so as to generate the light of the second primary color;

a third light-transmitting phase adjustment layer, disposed between the third sub-electrode and the light-emitting layer, and spaced from the first light-transmitting phase adjustment layer and the second light-transmitting phase adjustment layer, respectively, for adjusting a resonant wavelength of a resonant cavity between the third sub-electrode and the second electrode to a wavelength of light of a third primary color to generate light of the third primary color;

and the second electrode is arranged on the surface of the light-emitting layer far away from the light-transmitting phase adjusting layer, wherein at least one of the first electrode and the second electrode is a light-transmitting electrode.

In one optional embodiment, the thickness of the first light-transmitting phase adjustment layer is determined by the wavelength and the reflection phase of the light of the first primary color according to a light wave interference enhancement formula, the thickness of the second light-transmitting phase adjustment layer is determined by the wavelength and the reflection phase of the light of the second primary color according to a light wave interference enhancement formula, and the thickness of the third light-transmitting phase adjustment layer is determined by the wavelength and the reflection phase of the light of the third primary color according to a light wave interference enhancement formula.

In one optional embodiment, the optical wave interference enhancement formula is:

wherein λ is a resonant wavelength of a resonant cavity between the first electrode and the second electrode, d is a distance between a luminescent quantum dot in the luminescent layer and the reflective electrode, θ is an angle between a normal and a light of the first primary color, a light of the second primary color, or a light of the third primary color, Φ is a reflection phase shift of the light of the first primary color, the light of the second primary color, or the light of the third primary color, n is an average refractive index of a material between the luminescent quantum dot in the luminescent layer and the reflective electrode, and m is a positive integer not equal to 0.

In one optional embodiment, the first light-transmission phase adjustment layer, the second light-transmission phase adjustment layer, and the third light-transmission phase adjustment layer are all made of a transparent material.

In one optional embodiment, the light-emitting layer includes: the light-emitting diode comprises a hole injection layer, a hole transport layer, a quantum dot light-emitting layer and an electron transport layer which are sequentially stacked from bottom to top.

In one optional embodiment, the quantum dots of the first primary color are red quantum dots, the quantum dots of the second primary color are green quantum dots, and the quantum dots of the third primary color are blue quantum dots.

In an alternative embodiment, the light emitting device further includes: and the metal buffer layer is arranged between the light-emitting layer and the second electrode.

In one optional embodiment, the first electrode is a reflective electrode, and the second electrode is a translucent electrode; or the first electrode is a semitransparent electrode, and the second electrode is a reflecting electrode.

In a second aspect, there is provided a display device comprising:

a plurality of the above light emitting devices, a plurality of the light emitting device matrices being arranged in the same horizontal plane.

In a third aspect, there is provided a method for manufacturing a light emitting device, for manufacturing the light emitting device as described above, the method comprising:

preparing a first sub-electrode, a second sub-electrode and a third sub-electrode which are independent from each other on a cleaned substrate by using a first conductive material to form a first electrode;

preparing a first light-transmitting phase adjusting layer with the thickness of M on the surface of the first sub-electrode by using a light-transmitting conductive material, preparing a second light-transmitting phase adjusting layer with the thickness of N on the surface of the second sub-electrode, and preparing a third light-transmitting phase adjusting layer with the thickness of P on the surface of the third sub-electrode, wherein M < N < P;

spin-coating poly (3, 4-ethylenedioxythiophene) -polystyrene sulfonic acid solution, TFB chlorobenzene solution, octane solution of quantum dots and ethanol solution of ZnMgO nanoparticles on the surfaces of the first light-transmitting phase adjusting layer, the second light-transmitting phase adjusting layer and the third light-transmitting phase adjusting layer in sequence to form a hole injection layer, a hole transmission layer, a quantum dot light-emitting layer and an electron transmission layer which are sequentially stacked from bottom to top so as to form a light-emitting layer, wherein the octane solution of the quantum dots at least comprises quantum dots of a first primary color, quantum dots of a second primary color and quantum dots of a third primary color;

and preparing a second electrode on the surface of the light-emitting layer by using a second conductive material, wherein at least one of the first conductive material and the second conductive material is a light-transmitting conductive material.

The light-emitting device only needs to pattern the first light-transmitting phase adjusting layer, the second light-transmitting phase adjusting layer and the third light-transmitting phase adjusting layer, and does not need to pattern the quantum dot light-emitting layer, so that the damage to quantum dots caused by the process of patterning the quantum dots is avoided; secondly, the embodiment of the application adopts the photoetching technology to pattern the light-transmitting phase adjusting layer, thereby solving the problem of low resolution ratio of the prior art such as ink-jet printing; in the embodiment of the present application, an optical resonant cavity structure formed by the first electrode, the light-transmitting phase adjustment layer, the light-emitting layer, and the second electrode can accelerate the radiative recombination of excitons of resonant light, thereby enhancing the light-emitting efficiency of each quantum dot, and solving the technical problem that the full-color display effect of the current quantum dot light-emitting diode is not ideal in the prior art, thereby achieving the technical effect of improving the full-color display of the quantum dot light-emitting diode.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments or the conventional technologies of the present application, the drawings used in the descriptions of the embodiments or the conventional technologies will be briefly introduced below, it is obvious that the drawings in the following descriptions are only some embodiments of the present application, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 is a schematic structural diagram of a light emitting device according to an embodiment of the present application;

fig. 2 is a schematic structural diagram of a light emitting device according to an embodiment of the present application;

fig. 3 is a schematic view illustrating a light emitting principle of a light emitting device according to an embodiment of the present application;

fig. 4 is a schematic structural diagram of a light emitting device according to an embodiment of the present application;

FIG. 5 is a graph of an emission spectrum of a first primary color emission layer of a light emitting device according to one embodiment of the present application;

FIG. 6 is a graph of an emission spectrum of a second primary color emission layer of a light emitting device according to an embodiment of the present application;

FIG. 7 is a graph of an emission spectrum of a second primary color emission layer of a light emitting device according to one embodiment of the present application;

fig. 8 is a color gamut map of a light emitting device provided by an embodiment of the present application;

fig. 9 is a schematic structural diagram of a display device according to an embodiment of the present application;

fig. 10 is a flowchart of a method for manufacturing a light emitting device according to an embodiment of the present disclosure;

fig. 11 is a flowchart of a process for manufacturing a light emitting device according to an embodiment of the present application;

fig. 12 is a flowchart of a process for manufacturing a light emitting device according to an embodiment of the present disclosure;

fig. 13 is a flowchart of a process for manufacturing a light emitting device according to an embodiment of the present application;

fig. 14 is a flowchart of a process for manufacturing a light emitting device according to an embodiment of the present application;

fig. 15 is a flowchart of a manufacturing process of a light emitting device according to an embodiment of the present disclosure.

Description of reference numerals:

10. a light emitting device; 100. a first electrode; 110. a first sub-electrode; 120. a second sub-electrode; 130. a third sub-electrode; 200. a light emitting layer; 300. a light-transmitting phase adjustment layer; 310. a first light-transmitting phase adjustment layer; 320. a second light-transmitting phase adjustment layer; 330. a third light-transmitting phase adjustment layer; 400. a second electrode; 500. a metal buffer layer; 20. a display device; 201. a first light-transmitting layer; 202. a second light-transmitting layer; 203. and a third light-transmitting layer.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more clearly understood, a light emitting device, a display device and a method for manufacturing the light emitting device of the present application are described below by way of example with reference to the accompanying drawings

Further detailed description is made. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application.

The numbering of the components as such, e.g., "first", "second", etc., is used herein only to distinguish the objects as described, and does not have any sequential or technical meaning. The term "connected" and "coupled" when used in this application, unless otherwise indicated, includes both direct and indirect connections (couplings). In the description of the present application, it is to be understood that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", and the like, indicate orientations or positional relationships based on those shown in the drawings, and are used only for convenience in describing the present application and for simplicity in description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed in a particular orientation, and be operated, and thus, are not to be considered as limiting the present application.

In this application, unless expressly stated or limited otherwise, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through intervening media. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

Quantum Dot Light-Emitting Diodes (QLEDs) have become a new trend in the display field due to their unique advantages of high color purity, adjustable Light emission color, good stability, solution processibility, etc. In order to realize the full-color display of the quantum dot light-emitting diode, the quantum dot light-emitting layer must be patterned to form a red, green and blue QLED pixel array which is arranged side by side in parallel. Since quantum dots can only be deposited by a solution process, a series of technical challenges still exist in the solution patterning process, and the application of the QLED in full-color display is limited. The currently proposed methods for imaging quantum dot pixels mainly include three methods: the first mode is ink-jet printing, namely, quantum dots are prepared into ink, the ink is sprayed out by an ink-jet printer, and a quantum dot film with a preset pattern is deposited on a substrate, but the precision of the ink-jet printing is low, so that the resolution of the formed quantum dot film is low; the second mode is transfer printing, namely, a silicon wafer is made into a concave-convex imaging stamp, and quantum dots are transferred onto a film substrate by utilizing the adsorption force between the stamp and the quantum dots, but the transfer printing process is complex and is difficult to prepare in a large area; the third method is photolithography, i.e. mixing quantum dots with a ligand cross-linking agent and spin-coating to form a film, so that the quantum dots are cross-linked under the irradiation of ultraviolet light, thereby forming a stable film, and the unexposed part is washed away by a solvent, thereby finally forming a quantum dot pattern on the substrate, but the introduction of chemical additives such as the cross-linking agent can cause the performance of the quantum dots to be reduced. Therefore, the full-color display effect of the present quantum dot light-emitting diode is not ideal.

The embodiment of the application provides a light-emitting device which comprises a first electrode, a second electrode, a light-emitting layer and a light-transmitting phase adjusting layer, wherein the light-emitting layer can generate a mixed light beam containing a first primary color, a second primary color and a third primary color. The first sub-electrode, the second sub-electrode and the third sub-electrode in the first electrode work independently; when the driving signals are applied to the first sub-electrode and the second electrode, the first light-transmitting phase adjustment layer adjusts the resonant wavelength of the resonant cavity between the first sub-electrode and the second electrode to the wavelength of the light of the first primary color to convert the mixed light beam into the light of the first primary color; when the driving signals are applied to the second sub-electrodes and the second electrodes, the second light-transmitting phase adjustment layer adjusts the resonant wavelength of the resonant cavity between the second sub-electrodes and the second electrodes to the wavelength of the light of the second primary color to convert the mixed light beam into the light of the second primary color; when the driving signal is applied to the third sub-electrode and the second electrode, the third light-transmitting phase adjustment layer adjusts the resonance wavelength of the resonant cavity between the third sub-electrode and the second electrode to the wavelength of the light of the third primary color to convert the mixed light beam into the light of the third primary color. According to the embodiment of the application, only the first light-transmitting phase adjusting layer, the second light-transmitting phase adjusting layer and the third light-transmitting phase adjusting layer need to be patterned, and the quantum dot light-emitting layer does not need to be patterned, so that the quantum dot is prevented from being damaged in the process of patterning the quantum dot; secondly, the embodiment of the application adopts the photoetching technology to pattern the light-transmitting phase adjusting layer, thereby solving the problem of low resolution ratio of the prior art such as ink-jet printing; in the embodiment of the present application, an optical resonant cavity structure formed by the first electrode, the light-transmitting phase adjustment layer, the light-emitting layer, and the second electrode can accelerate the radiative recombination of excitons of resonant light, thereby enhancing the light-emitting efficiency of each quantum dot, and solving the technical problem that the full-color display effect of the current quantum dot light-emitting diode is not ideal in the prior art, thereby achieving the technical effect of improving the full-color display of the quantum dot light-emitting diode.

The light-emitting device provided by the embodiment of the application can be applied to any display equipment, such as micro display, Augmented Reality (AR) and Virtual Reality (VR) display, head-mounted display, a television, a mobile phone screen, a flat panel display and the like.

Referring to fig. 1, an embodiment of the present application provides a light emitting device 10, which includes a first electrode 100, a light emitting layer 200, a light transmitting phase adjustment layer 300, and a second electrode 400.

Referring to fig. 2, the first electrode 100 includes a first sub-electrode 110, a second sub-electrode 120 and a third sub-electrode 130, which are independent of each other, and are respectively connected to a driving transistor or an electrode of an external power source when in use, so as to drive the light emitting layer 200 to emit light. The first sub-electrode 110, the second sub-electrode 120 and the third sub-electrode 130 are planar electrodes to have a larger contact area with the light emitting layer 200, thereby maximally ensuring the electrical energy conduction performance. The first sub-electrode 110, the second sub-electrode 120, and the third sub-electrode 130 may be made of any non-transparent conductive material, such as aluminum, silver, and the like, with high reflectivity, so as to use the first electrode 100 as a reflective electrode, and the first sub-electrode 110, the second sub-electrode 120, and the third sub-electrode 130 may also be made of a transparent or semi-transparent conductive material, such as metal oxide or thin metal, so as to use the first electrode 100 as a transparent electrode for emitting light.

The light emitting layer 200 at least includes a quantum dot light emitting layer made of a mixture of quantum dots of a first primary color, quantum dots of a second primary color, and quantum dots of a third primary color, and the quantum dot light emitting layer is used for generating a mixed light beam including the first primary color, the second primary color, and the third primary color. The primary colors are "primary colors" that cannot be obtained by mixing other colors, and since human eyes perceive pyramidal cells of three different colors, red, green, and blue, a color space can be generally expressed by three primary colors, i.e., three primary colors "red", "green", and "blue". The first primary color in this embodiment is any one of "red", "green", and "blue", and the second primary color is different from the first primary color, then the quantum dots of the first primary color emit light of the first primary color, the quantum dots of the second primary color emit light of the second primary color, the quantum dots of the third primary color emit light of the third primary color, and the light emitting layer 200 is used to generate a mixed light beam including the first primary color, the second primary color, and the third primary color. It should be noted that the light emitting layer 200 further includes other layers, such as a hole injection layer, a hole transport layer, a quantum dot light emitting layer (a mixed layer formed by quantum dots of a first primary color, quantum dots of a second primary color, and quantum dots of a third primary color in this embodiment), an electron transport layer, and the like, which are sequentially stacked on top of and below the light emitting layer, and the layers respectively perform different functions of carrier transport and energy release.

Meanwhile, the light emitting layer 200 is formed by mixing the quantum dots of the first primary color, the quantum dots of the second primary color and the quantum dots of the third primary color, and the quantum dots of the first primary color, the quantum dots of the second primary color and the quantum dots of the third primary color are mixed according to a certain proportion to form the light emitting layer 200. Meanwhile, the band gap widths of the first primary color, the second primary color and the third primary color are different, and the energies of the first primary color, the second primary color and the third primary color are also different, so that the three colors are mixed to form the same light emitting layer 200, and under the modulation of resonance control between the first electrode 100 and the second electrode 400, non-radiative energy transfer between quantum dots of different primary colors can be promoted during light emission, so that the light emitting efficiency and the light emitting effect of the light emitting device 10 provided by the embodiment of the application are further improved.

Referring to fig. 2, the light-transmitting phase adjustment layer 300 is disposed between the first electrode 100 and the light-emitting layer 200, and the light-transmitting phase adjustment layer 300 includes: a first light-transmitting phase adjustment layer 310, a second light-transmitting phase adjustment layer 320, and a third light-transmitting phase adjustment layer 330.

The first light-transmitting phase adjustment layer 310 is disposed between the first sub-electrode 110 and the light-emitting layer 200, sequentially arranged with the second light-transmitting phase adjustment layer 320 and the third light-transmitting phase adjustment layer 330, and disposed at an interval from each other, and the first light-transmitting phase adjustment layer 310 adjusts a resonant wavelength of a resonant cavity between the first sub-electrode 110 and the second electrode 400 to a wavelength of light of the first primary color, so as to convert the mixed light beam into light of the first primary color. And a second light-transmitting phase adjustment layer 320 disposed between the second sub-electrode 120 and the light-emitting layer 200, for adjusting a resonant wavelength of the resonant cavity between the second sub-electrode 120 and the second electrode 400 to a wavelength of light of the second primary color, so as to convert the mixed light beam into light of the first primary color. The third light-transmitting phase adjustment layer 330 is disposed between the third sub-electrode 130 and the light-emitting layer 200, and is spaced apart from the first light-transmitting phase adjustment layer 310 and the second light-transmitting phase adjustment layer 320, respectively, to adjust the resonant wavelength of the resonant cavity between the third sub-electrode 130 and the second electrode 400 to the wavelength of the light of the third primary color, so as to convert the mixed light beam into the light of the third primary color. The modes of the first light-transmission phase adjustment layer 310, the second light-transmission phase adjustment layer 320, and the third light-transmission phase adjustment layer 330 adjusting the resonance wavelength of the resonant cavity between the first electrode 100 and the second electrode 400 include, but are not limited to, the following two: in the first manner, the first light-transmitting phase adjustment layer 310, the second light-transmitting phase adjustment layer 320, and the third light-transmitting phase adjustment layer 330 are provided with different phase adjustment materials to realize different phase adjustments; in the second way, the thicknesses of the first light-transmission phase adjustment layer 310, the second light-transmission phase adjustment layer 320, and the third light-transmission phase adjustment layer 330 are set to different values, thereby adjusting the resonance wavelength of the resonant cavity between the first electrode 100 and the second electrode 400. It should be noted that, in this embodiment, specific materials, thicknesses, and the like of the first light-transmitting phase adjustment layer 310, the second light-transmitting phase adjustment layer 320, and the third light-transmitting phase adjustment layer 330 are not limited at all, and only the function of respectively adjusting the resonant wavelength of the resonant cavity between the first electrode 100 and the second electrode 400 to the wavelength of the light of the first primary color, the wavelength of the light of the second primary color, and the wavelength of the light of the third primary color to convert the mixed light beam into the light of the first primary color, the second primary color, and the third primary color needs to be satisfied.

The second electrode 400 is disposed on the surface of the light-emitting layer 200 away from the light-transmitting phase adjustment layer 300, wherein at least one of the first electrode 100 and the second electrode 400 is a light-transmitting electrode. The second electrode 400 has the same function as the first electrode 100, and both of them are used as driving electrodes, and when in use, the driving electrodes are connected to an external power source to interact with the first electrode 100 to drive the light-emitting layer 200 to emit light. The second electrode 400 may be a planar electrode to have a larger contact area with the light emitting layer 200, thereby maximally securing the electric energy conduction performance. The second electrode 400 may be made of any non-transparent conductive material such as gold, silver, and other materials with high reflectivity, etc. to make the second electrode 400 a reflective electrode, and the second electrode 400 may also be made of a semi-transparent or transparent conductive material such as a thin layer of metal or metal oxide, etc. to make the second electrode 400 a transparent electrode. However, it should be noted that at least one of the first electrode 100 and the second electrode 400 is a transparent electrode as a light emitting surface.

The working principle of the light emitting device 10 provided by the embodiment of the application is as follows:

when in use, the first electrode 100 and the second electrode 400 are electrically connected to the positive and negative electrodes of an external power source, respectively, and the light emitting layer 200 emits light when energized. Wherein the light emitting layer 200 includes quantum dots of a first primary color, quantum dots of a second primary color, and quantum dots of a third primary color, and the light emitting layer 200 generates a mixed light beam of the first primary color, the second primary color, and the third primary color. The mixed light beams are reflected back and forth by the first electrode 100 and the second electrode 400, multiple light beam interference occurs, when the phase difference of the light reflected back and forth at a certain wavelength is just an integral multiple of 2 pi, the light at the certain wavelength is enhanced in resonance, and the light at other wavelengths is finally cancelled out in resonance because the resonance condition is not met. The resonance wavelength of the resonance control between the first electrode 100 and the second electrode 400 can be adjusted by the light-transmissive phase layer. The light-transmitting phase adjustment layer 300 includes a first light-transmitting phase adjustment layer 310, a second light-transmitting phase adjustment layer 320, and a third light-transmitting phase adjustment layer 330, the first light-transmitting phase adjustment layer 310 adjusts the resonant wavelength of the resonant cavity between the first sub-electrode 110 and the second electrode 400 to the wavelength of the light of the first primary color, so that the light of the first primary color is enhanced in resonance, and the light of the other primary colors is cancelled due to detuning, and finally the mixed light beam is converted into the light of the first primary color; the second light-transmitting phase adjustment layer 320 adjusts the resonant wavelength of the resonant cavity between the second sub-electrode 120 and the second electrode 400 to the wavelength of the light of the second primary color, so that the light of the second primary color is enhanced in resonance, and the light of the other primary colors is cancelled due to detuning, and finally the mixed light beam is converted into the light of the second primary color; the third light-transmitting phase adjustment layer 330 adjusts the resonant wavelength of the resonant cavity between the third sub-electrode 130 and the second electrode 400 to the wavelength of the light of the second primary color, so that the light of the second primary color is resonantly enhanced, and the lights of other primary colors are cancelled due to detuning, and finally the mixed light beam is converted into the light of the third primary color. Thereby obtaining monochromatic light of the first primary color, the second primary color and the third primary color respectively, namely forming a full-color pixel. In the subsequent use process, the light with different colors can be generated and emitted from the light-transmitting electrode in the first electrode 100 or the second electrode 400 only by adjusting the relative proportion and intensity among the light with the first primary color, the light with the second primary color and the light with the third primary color.

The above-described light emitting device 10 includes a first electrode 100, a second electrode 400, a light emitting layer 200, and a light transmitting phase adjusting layer 300, wherein the light emitting layer 200 can generate a mixed light beam including a first primary color, a second primary color, and a third primary color. The first sub-electrode 110, the second sub-electrode 120, and the third sub-electrode 130 in the first electrode 100 operate independently of each other, and when a driving signal is applied to the first sub-electrode 110 and the second electrode 400, the first light-transmitting phase adjustment layer 310 adjusts a resonant wavelength of a resonant cavity between the first sub-electrode 110 and the second electrode 400 to a wavelength of light of a first primary color to convert the mixed light beam into light of the first primary color; when the driving signal is applied to the second sub-electrode 120 and the second electrode 400, the second light-transmitting phase adjustment layer 320 adjusts the resonance wavelength of the resonant cavity between the second sub-electrode 120 and the second electrode 400 to the wavelength of the light of the second primary color to convert the mixed light beam into the light of the second primary color; when the driving signal is applied to the third sub-electrode 130 and the second electrode 400, the third light-transmitting phase adjustment layer 330 adjusts the resonant wavelength of the resonant cavity between the third sub-electrode 130 and the second electrode 400 to the wavelength of the light of the third primary color to convert the mixed light beam into the light of the third primary color. In the embodiment of the application, only the first light-transmitting phase adjustment layer 310, the second light-transmitting phase adjustment layer 320 and the third light-transmitting phase adjustment layer 330 need to be patterned, and the quantum dot light-emitting layer does not need to be patterned, so that the quantum dot is prevented from being damaged in the process of patterning the quantum dot; secondly, the embodiment of the application adopts the photoetching technology to pattern the light-transmitting phase adjusting layer, thereby solving the problem of low resolution ratio of the prior art such as ink-jet printing; in the embodiment of the present application, the energy of the quantum dots of the first primary color, the energy of the quantum dots of the second primary color, and the energy of the quantum dots of the third primary color in the light-emitting layer are different, and energy transfer exists among the quantum dots of different primary colors, so that energy can be supplemented and promoted mutually during light emission.

Meanwhile, the Light Emitting device 10 provided in the embodiment of the present application forms a resonant cavity between the first electrode 100 and the second electrode 400, which is based on the emission of the quantum Dot Light Emitting layer, and is substantially completely different from the conventional white Light oled (organic Light Emitting diodes).

In the conventional white light OLED, because the light emitting layers of different primary colors are stacked, energy transfer between the stacked light emitting layers is weak, and the resonant cavity only plays a role in modulating the spectrum, and cannot regulate and control the distribution of excitons between the light emitting layers of different primary colors. In the white light OLED, the obtained resonant color light can be coherently increased in the cavity to be enhanced to be emitted; most of the detuned excitons are not converted into resonant excitons by the FRET energy transfer mechanism, and finally disappear due to interference cancellation. In other words, in the white OLED, when the cavity length of the resonant cavity satisfies the resonance condition of a certain color light, only the color light can be output, and other color lights are suppressed to finally disappear. Therefore, in a resonant cavity white OLED, the resonant cavity has high loss of color conversion (from white light to monochromatic light), resulting in inefficient output of monochromatic light and often associated with parasitic stray light.

The light emitting device 10 provided in the embodiment of the present application is based on a white light QLED, and the light emitting layer 200 is formed by mutually mixing the first primary color quantum dot, the second primary color quantum dot, and the third primary color quantum dot, and since the first primary color quantum dot, the second primary color quantum dot, and the third primary color quantum dot are in close contact with each other, exciton energy can be transferred among different primary color quantum dots, and the resonant cavity can be used to regulate the lifetime of excitons, so that the transfer of exciton energy among different primary color quantum dots can be regulated.

Under the continuous stimulation of the resonant cavity optical field and the resonance light, the exciton of any primary color is converted from spontaneous radiation to stimulated radiation when the light of the primary color meets the resonance condition. Compared with spontaneous radiation, the life of stimulated radiation is obviously shortened, and the shortening proportion is determined by Purcell Factor. Therefore, the light-emitting device of the embodiment accelerates the radiative recombination of excitons through the resonant cavity, thereby reducing the probability of non-radiative recombination of excitons quenched by defects, regulating and controlling the energy transfer of excitons among quantum dots with different primary colors, and being beneficial to improving the luminous efficiency. Such as: when the cavity length of the resonant cavity meets the resonance condition of the light of the first primary color, the light of the first primary color is enhanced in resonance in the resonant cavity, the service life of the exciton of the first primary color is obviously reduced, and the recombination rate is increased, so that the transfer of the exciton from the quantum dot of the second primary color and the quantum dot of the third primary color to the quantum dot of the first primary color is effectively promoted, most of the injected exciton is finally recombined in the quantum dot of the first primary color, and the luminous efficiency of the quantum dot of the first primary color is improved. That is, in the white light QLED, the loss of the color conversion (from white light to monochromatic light) of the resonant cavity is low, the efficiency of the monochromatic light obtained by the conversion is high, and the light emitting effect is better.

In an alternative embodiment of the present application, the thickness of the first light-transmission phase adjustment layer 310 is determined by the wavelength and the reflection phase of the light of the first primary color according to the optical wave interference enhancement formula, the thickness of the second light-transmission phase adjustment layer 320 is determined by the wavelength and the reflection phase of the light of the second primary color according to the optical wave interference enhancement formula, and the thickness of the third light-transmission phase adjustment layer 330 is determined by the wavelength and the reflection phase of the light of the third primary color according to the optical wave interference enhancement formula. That is, the phase adjustment manner in the present application is to adjust by the thickness of the light-transmitting phase adjustment layer 300. Wherein, the optical wave interference enhancement formula can be:

(1) where λ is the resonant wavelength of the resonant cavity between the first electrode 100 and the second electrode 400; d is the distance between the luminescent quantum dot in the luminescent layer 200 and the reflective electrode, θ is the angle between the light of the first primary color, the light of the second primary color or the light of the third primary color and the normal, φ is the reflection phase shift of the light of the first primary color, the light of the second primary color or the light of the third primary color, n is the average refractive index of the material between the luminescent quantum dot in the luminescent layer and the reflective electrode, and m is a positive integer not equal to 0;

d is determined as follows:

for light of a first primary color: d ═ d₂₀+d₃₁

For light of the second primary color: d ═ d₂₀+d₃₂

For light of a third primary color: d ═ d₂₀+d₃₃

Wherein d is₂₀Thickness of the hole injection layer and the hole transport layer in the light-emitting layer 200, d₃₁Thickness of the first light-transmitting phase adjusting layer 310, d₃₂Thickness of the second light-transmitting phase adjusting layer 320, d₃₃The thickness of the third light-transmitting phase adjustment layer 330.

Referring to fig. 3, in the present embodiment, if the first electrode 100 is a reflective electrode and the second electrode 400 is a transparent electrode, for example, for a quantum dot P of the first primary color, light emitted from the quantum dot P passing through the first electrode 100 includes a first light path (as shown by a dotted line in fig. 3), the light emitted from the quantum dot P of the first primary color passes through the reflective electrode, that is, the first sub-electrode 110 in the first electrode 100, and then is reflected by the transparent electrode, that is, the second electrode 400; a first resonant cavity is formed among the first sub-electrode 110, the first light-transmitting phase adjustment layer 310, the light-emitting layer 200 and the second electrode 400 in the first electrode 100, and when the thickness d of the first resonant cavity satisfies the above formula (1), the resonant wavelength of the first resonant cavity is very close to or even equal to the wavelength of the light of the first primary color, constructive interference occurs between the lights of different optical paths of the light of the first primary color, and the lights of the second primary color and the third primary color do not satisfy the resonance condition to be suppressed, so that the light of the mixed light beam is converted into monochromatic light of the first primary color.

If the first electrode 100 is a reflective electrode and the second electrode 400 is a semitransparent electrode, the light passing through the first electrode 100 further includes a second light path, a part of light emitted by the quantum dots P of the first primary color is directly emitted from the semitransparent electrode, and another part of light (shown by a solid line in fig. 3) is reflected by the semitransparent electrode to reach the first electrode 100, is reflected by the first sub-electrode 110 in the first electrode 100, and finally is emitted from the second electrode 400, i.e., the semitransparent electrode. The multiple reflections can further enhance the interference effect of the first resonant cavity of the embodiment of the present application on the light of the first primary color, so as to suppress the light of the second primary color and the light of the third primary color, and further improve the display purity of the light emitting device 10 provided by the embodiment of the present application.

Similarly, a second resonant cavity is formed between the light emitting layer 200 and the second light-transmitting phase adjustment layer 320, and under the driving of the second sub-electrode 120 in the first electrode 100 and the second electrode 400, when the thickness d of the second resonant cavity satisfies the above formula (1), the resonant wavelength of the second resonant cavity is very close to, even equal to, the wavelength of the light of the second primary color, constructive interference is generated between the lights of different optical paths of the light of the second primary color, and monochromatic lights of the first primary color and the third primary color are suppressed at the same time, so that the light of the mixed light beam is converted into monochromatic light of the second primary color. A third resonant cavity is formed between the light-emitting layer 200 and the third light-transmitting phase adjustment layer 300, and when the thickness d of the third resonant cavity satisfies the above formula (1) under the driving of the third sub-electrode 130 in the first electrode 100 and the second electrode 400, the resonant wavelength of the third resonant cavity is very close to, or even equal to, the wavelength of the light of the third primary color, so that constructive interference is generated between the lights of different optical paths of the light of the third primary color, and monochromatic lights of the first primary color and the second primary color are suppressed at the same time, so that the light of the mixed light beam is converted into monochromatic light of the third primary color.

The light-emitting device 10 provided in the embodiment of the present application adjusts the resonant wavelength of the resonant cavity between the first electrode 100 and the second electrode 400 by adjusting the thicknesses of the first light-transmitting phase adjustment layer 310, the second light-transmitting phase adjustment layer 320, and the third light-transmitting phase adjustment layer 330, and the first light-transmitting phase adjustment layer 310, the second light-transmitting phase adjustment layer 320, and the third light-transmitting phase adjustment layer 330 are all made of light-transmitting materials, which do not affect the light-emitting performance of the light-emitting device 10. Meanwhile, the mixed light beam is converted into monochromatic light of the first, second and third primary colors through the first, second and third light-transmitting phase adjustment layers 310, 320 and 330, respectively, and the color rendering purity is high.

In an alternative embodiment of the present application, the quantum dots of the first primary color are red quantum dots, the quantum dots of the second primary color are green quantum dots, the quantum dots of the third primary color are blue quantum dots, and the band gap widths of the lights of the three colors of red, green, and blue are blue, green, and red in sequence from wide to narrow, that is, the energy of the blue light is the highest, and when the light is emitted, the blue light easily transfers energy to the green light and the red light, resulting in the transfer of non-radiative energy, that is, the light emission of the green quantum dots and the red quantum dots is promoted by the blue quantum dots, and similarly, the light emission of the red quantum dots is promoted by the blue quantum dots and the green quantum dots. Under the effect of the resonant cavity between the first electrode 100 and the second electrode 400, when red light meets the resonance condition, the resonant cavity can accelerate the transfer of excitons from the blue quantum dots and the green quantum dots to the red quantum dots, so that most of the injected excitons are finally compounded in the red quantum dots, and the improvement of the luminous efficiency of the red light is facilitated; when the green light meets the resonance condition, the resonant cavity can accelerate the transfer of excitons from the blue quantum dots to the green quantum dots and inhibit the transfer of the excitons from the green quantum dots to the red quantum dots, so that most of the injected excitons are finally compounded in the green quantum dots, and the luminous efficiency of the green light is improved; when the blue light meets the resonance condition, the resonant cavity can inhibit excitons from transferring from the blue quantum dots to the green quantum dots and the red quantum dots, so that most of the injected excitons are finally compounded in the blue quantum dots, and the luminous efficiency of the blue light is improved.

In an optional embodiment of the present application, the first light-transmitting phase adjustment layer 310, the second light-transmitting phase adjustment layer 320, and the third light-transmitting phase adjustment layer 330 are all made of transparent and conductive materials, so that the light-emitting layer 200 can be prevented from emitting a mixed light beam which is absorbed when passing through the light-transmitting phase adjustment layer 300, and the carrier injection efficiency is not affected, thereby ensuring the light-emitting effect of the light-emitting device provided in the embodiment of the present application.

Referring to fig. 4, in an alternative embodiment of the present application, the light emitting device 10 further includes: a metal buffer layer 500. The metal buffer layer 500 is disposed between the light emitting layer 200 and the second electrode 400, and the thickness of the light emitting layer 200 is generally nano-scale, and is very thin and weak, so that by disposing a metal buffer layer 500 on the surface of the light emitting layer 200, the light emitting layer 200 can be effectively prevented from being damaged due to too high energy when the second electrode 400 is fabricated, thereby ensuring the performance and the light emitting effect of the light emitting layer 200, and further improving the reliability of the light emitting device 10 provided in the embodiment of the present application.

In an alternative embodiment of the present application, in a first aspect, the first electrode 100 is a reflective electrode, and the second electrode 400 is a translucent electrode, so that the light emitting device 10 provided in the embodiment of the present application is a top emission device, and the top emission device has a larger aperture ratio, and can obtain higher light emitting power at the same current density, thereby improving the light emitting effect of the light emitting device 10 provided in the embodiment of the present application. In the second aspect, the first electrode 100 is a semitransparent electrode, and the second electrode 400 is a reflective electrode. Therefore, the light emitting device 10 provided by the embodiment of the application is a bottom emitting device, light is emitted from the lower part, and the anti-interference performance of the emitted light beam is better, so that the light emitting effect of the light emitting device 10 provided by the embodiment of the application is improved. Meanwhile, the light-emitting electrode is set as the translucent electrode, so that the interference effect of the formed interference cavity can be effectively enhanced, and the display purity and the display efficiency of the light-emitting device 10 provided by the embodiment of the application are improved.

Fig. 5 is a graph showing an electroluminescence spectrum of light of a first primary color (red) of the light emitting device 10 provided in the embodiment of the present application, fig. 6 is a graph showing an electroluminescence spectrum of light of a second primary color (green) of the light emitting device 10 provided in real time in the present application, and fig. 7 is a graph showing an electroluminescence spectrum of light of a third primary color (blue) of the light emitting device 10 provided in real time in the present application. From fig. 5-7, it can be clearly seen that, under the driving of the external power source of 3V-5V, the lights of the first primary color, the second primary color and the third primary color can maintain high-purity monochromatic lights, and the half-width of the light-emitting peak is reduced from about 30nm to about 20nm as shown in fig. 5-7. Therefore, the light emitting device 10 provided in the embodiment of the present application can directly convert white light, i.e., the mixed light beam in the above description, into monochromatic light of the first primary color, the second primary color, and the third primary color without using a color filter in the conventional scheme, thereby greatly reducing the cost for using the color filter, and reducing the manufacturing cost for using at least 3 times of photolithography when the color filter is used to emit light of different primary colors, and the light emitting device 10 is simple in manufacturing process and can be mass-produced.

As shown in fig. 8, which is a color gamut diagram of the light emitting device 10 in the embodiment of the present application, it can be clearly seen from fig. 8 that when the first primary color, the second primary color, and the third primary color are used as display pixel points, the highest color gamut of the light emitting device 10 can reach 111%, which is far higher than the highest standard in the industry, and further color filters are not required to be introduced at all.

Referring to fig. 9, an embodiment of the present application provides a display device 20, including: the plurality of light emitting devices 10 are arranged in a matrix on the same horizontal plane, and collectively form the display device 20. The advantageous effects of the light emitting device 10 have been explained in detail in the above embodiments, and are not described in detail herein.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

Referring to fig. 10, an embodiment of the present application provides a method for manufacturing a light emitting device 10, for manufacturing the light emitting device 10, the method including the following steps 101 to 104:

in step 101, referring to fig. 11, a first conductive material is used to prepare a first sub-electrode 110, a second sub-electrode 120, and a third sub-electrode 130, which are independent of each other, on a cleaned substrate, so as to form a first electrode 100.

On the cleaned glass substrate, three Ag electrodes are prepared by a metal mask sputtering or photolithography imaging method, and three independent sub-electrodes, i.e., a first sub-electrode 110, a second sub-electrode 120, and a third sub-electrode 130 are formed, and the three sub-electrodes jointly constitute the first electrode 100.

Step 102, preparing a first light-transmitting phase adjusting layer with a thickness of M on the surface of the first sub-electrode by using a light-transmitting conductive material, preparing a second light-transmitting phase adjusting layer with a thickness of N on the surface of the second sub-electrode, and preparing a third light-transmitting phase adjusting layer with a thickness of P on the surface of the third sub-electrode.

Wherein M < N < P. Referring to fig. 12 to 14, a first light-transmitting layer 201 with a first thickness is prepared on the surface of each sub-electrode by using a metal mask for sputtering or photolithography patterning, the thicknesses of the plurality of first light-transmitting layers 201 are all equal, and the material of the first light-transmitting layer 201 may be a transparent conductive oxide or the like. If the number of the first light-transmitting layers 201 is 3, a transparent conductive oxide layer with a second thickness is continuously prepared on the surfaces of two of the first light-transmitting layers 201 by using a metal mask sputtering or photoetching patterning method, so that two second light-transmitting layers 202 are formed. Then, a transparent conductive oxide layer with a third thickness is prepared on the surface of one of the two second light-transmitting layers 202 by using a metal mask sputtering or photolithography patterning method, so that 1 third light-transmitting layer 203 is formed. At this time, the first light transmission phase adjustment layer 310, the second light transmission phase adjustment layer 320, and the third light transmission phase adjustment layer 330, which are sequentially increased in height, are formed.

Step 103, please refer to fig. 15, in which a poly (3, 4-ethylenedioxythiophene) -polystyrene sulfonic acid solution, a TFB chlorobenzene solution, an octane solution of quantum dots, and an ethanol solution of ZnMgO nanoparticles are sequentially spin-coated on the surfaces of the first light-transmitting phase adjustment layer 310, the second light-transmitting phase adjustment layer 320, and the third light-transmitting phase adjustment layer 330, so as to form the light-emitting layer 200 including a hole injection layer, a hole transport layer, a quantum dot light-emitting layer, and an electron transport layer, which are sequentially stacked from bottom to top.

The octane solution of the quantum dots at least comprises quantum dots of a first primary color, quantum dots of a second primary color and quantum dots of a third primary color, and the colors of the first primary color, the second primary color and the third primary color are different. A light-emitting layer 200 is prepared by spin coating in the surfaces of the first light-transmitting layer 201, the second light-transmitting layer 202, and the third light-transmitting layer 203 and in the gaps between the light-transmitting phase-adjusting layers. For example, firstly, the mass ratio of red quantum dots, green quantum dots and blue quantum dots is 1: 12: 39, then spin-coating at a rotating speed of 3000r/min to form a film, and finally baking at 100 ℃ for 5min to form the light-emitting layer 200. For example, the following steps 301 to 304 may be included:

301, spin-coating a poly (3, 4-ethylenedioxythiophene) -polystyrene sulfonic acid solution at a rotating speed of 3000r/min to form a film, and then baking at 150 ℃ for 15min to form a hole injection layer;

step 302, spin-coating 8mg/ml TFB chlorobenzene solution on the surface of the hole injection layer at the rotating speed of 3000r/min, and then baking for 10min at 110 ℃ to form a hole transport layer;

step 303, preparing a 10mg/mL n-octane solution of red quantum dots, a 10mg/mL n-octane solution of green quantum dots and a 10mg/mL n-octane solution of blue quantum dots into red quantum dots, green quantum dots and blue quantum dots according to a volume ratio of 1: 12: 39, spin-coating the mixed solution on the surface of the hole transport layer at a rotating speed of 3000r/min to form a film, and baking at the temperature of 100 ℃ for 5min to form a light-emitting layer 200;

step 304, spin-coating 20mg/ml ethanol solution of ZnMgO nanoparticles onto the surface of the mixed light-emitting layer at a rotation speed of 2500r/min, and then baking at 100 ℃ for 10min to form a ZnMgO nanoparticle film to form an electron transport layer, thereby obtaining the light-emitting layer 200 sequentially comprising a hole injection layer, a hole transport layer, a mixed light-emitting layer and an electron transport layer from bottom to top.

Step 104, please continue to refer to fig. 15, a second electrode 400 is formed on the surface of the light-emitting layer 200 by using a second conductive material.

At least one of the first conductive material and the second conductive material is a transparent conductive material. If the first electrode 100 is a non-transparent electrode, the second electrode 400 must be a transparent electrode, i.e. made of a transparent conductive material, and a semitransparent Ag film with a thickness of 20nm can be prepared as the second electrode 400 by a metal mask sputtering or photolithography imaging method.

In the method for manufacturing the light emitting device 10 provided in the embodiment of the present application, only the light-transmitting phase adjustment layers need to be subjected to photolithography, so that the thicknesses of the different light-transmitting phase adjustment layers are different, and the cavity lengths of the corresponding resonant cavities respectively satisfy the resonance conditions of different primary colors, so that the mixed light beams in the light emitting layer 200, that is, the white light, are respectively converted into monochromatic lights of the first primary color, the second primary color, and the third primary color with high saturation. Meanwhile, the photoetching technology is mature, the process is simple, the cost is low, the nano-scale graphical pixel can be easily realized, and the application of various areas and various resolutions including large-area televisions (the resolution is more than 200ppi), mobile phones (>400ppi), micro-displays (>3000ppi) and AR/VR (>5000ppi) is met.

It should be understood that, although the steps in the flowchart are shown in order as indicated by the arrows, the steps are not necessarily performed in order as indicated by the arrows. The steps are not performed in the exact order shown and described, and may be performed in other orders, unless explicitly stated otherwise. Moreover, at least some of the steps in the figures may include multiple steps or multiple stages, which are not necessarily performed at the same time, but may be performed at different times, and the order of execution of the steps or stages is not necessarily sequential, but may be performed alternately or in alternation with other steps or at least some of the other steps or stages.

The above-mentioned embodiments only express several embodiments of the present application, and the description thereof is more specific and detailed, but not construed as limiting the claims. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the concept of the present application, which falls within the scope of protection of the present application. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. A light emitting device, comprising:

the second electrode is arranged on the surface of the light-emitting layer far away from the first electrode, wherein at least one of the first electrode and the second electrode is a light-transmitting electrode;

and the third light-transmitting phase adjusting layer is arranged between the third sub-electrode and the light-emitting layer, is respectively arranged at intervals with the first light-transmitting phase adjusting layer and the second light-transmitting phase adjusting layer, and is used for adjusting the resonant wavelength of the resonant cavity between the third sub-electrode and the second electrode to the wavelength of light of a third primary color so as to generate the light of the third primary color.

2. The light-emitting device according to claim 1, wherein a thickness of the first light-transmitting phase adjustment layer is determined by a wavelength and a reflection phase of the light of the first primary color according to a light wave interference enhancement formula, a thickness of the second light-transmitting phase adjustment layer is determined by a wavelength and a reflection phase of the light of the second primary color according to a light wave interference enhancement formula, and a thickness of the third light-transmitting phase adjustment layer is determined by a wavelength and a reflection phase of the light of the third primary color according to a light wave interference enhancement formula.

3. The light emitting device of claim 2, wherein the optical wave interference enhancement formula is:

4. The light-emitting device according to claim 1, wherein the first light-transmitting phase adjustment layer, the second light-transmitting phase adjustment layer, and the third light-transmitting phase adjustment layer are each made of a transparent material.

5. The light-emitting device according to claim 1, wherein the light-emitting layer comprises: the light-emitting diode comprises a hole injection layer, a hole transport layer, a quantum dot light-emitting layer and an electron transport layer which are sequentially stacked from bottom to top.

6. The light-emitting device according to claim 1, wherein the quantum dots of the first primary color are red quantum dots, the quantum dots of the second primary color are green quantum dots, and the quantum dots of the third primary color are blue quantum dots.

7. The light-emitting device according to claim 1, further comprising: and the metal buffer layer is arranged between the light-emitting layer and the second electrode.

8. The light-emitting device according to claim 1, wherein the first electrode is a reflective electrode, and wherein the second electrode is a translucent electrode; or the first electrode is a semitransparent electrode, and the second electrode is a reflecting electrode.

9. A display device, comprising:

a plurality of the light emitting devices of any one of claims 1-8, a plurality of the light emitting device matrices being arranged in a same horizontal plane.

10. A method for producing a light-emitting device, characterized by being used for producing the light-emitting device according to any one of claims 1 to 8, the method comprising: