CN111509027B

CN111509027B - QD display structure and display device

Info

Publication number: CN111509027B
Application number: CN202010474681.0A
Authority: CN
Inventors: 王琳琳; 尤娟娟
Original assignee: BOE Technology Group Co Ltd
Current assignee: BOE Technology Group Co Ltd
Priority date: 2020-05-29
Filing date: 2020-05-29
Publication date: 2022-07-22
Anticipated expiration: 2040-05-29
Also published as: CN111509027A

Abstract

The application discloses a QD display structure and a display device, which comprise a first substrate and a second substrate which are oppositely arranged, wherein a color film layer is arranged on one side of the first substrate close to the second substrate, and a quantum dot layer is formed on one side of the color film layer close to the second substrate; a blue EL layer is arranged on one side, close to the first substrate, of the second substrate, a cathode layer is arranged on the blue EL layer, a TFE film layer is further arranged on the cathode layer, a plurality of microstructures are arranged on the TFE film layer, and a composite material grows on each microstructure; the composite material has negative dielectric constant performance. According to the technical scheme provided by the embodiment of the application, the material with the negative dielectric constant is provided, the cathode layer with the negative dielectric constant or the microstructure is arranged, the material with the negative dielectric constant performance grows on the cathode layer, the material has the characteristics of small-angle light penetration and large-angle light reflection, secondary emergence is carried out on red and green light of a lower hemisphere scattered by the QD layer, and meanwhile, secondary absorption is carried out on the scattered blue light, so that the QD conversion efficiency is improved.

Description

QD display structure and display device

Technical Field

The present invention relates generally to the field of display technology, and more particularly to QD display structures and display devices.

Background

At present, the applications of quantum dots in the display technology field are roughly divided into two types, namely electroluminescence and photoluminescence, and mainly include the following three applications: (1) quantum dot backlights (QDEFs) based on photoluminescence characteristics; (2) quantum dot dichroic filters (QDCFs) based on photoluminescence characteristics; (3) quantum dot light emitting diodes (QD-LEDs) based on electroluminescent properties.

The QDEF technology is mainly used in products using quantum dot technology, such as commercially available samsung SUHD televisions, and the specific method is to insert a quantum thin film containing quantum dots on a light-emitting backlight module, so that light passing through the thin film shows color through liquid crystals and color filters. The structure is not different from the LCD mode, but quite good color reproduction effect can be obtained by QDEF technology. Unlike QDEF, which adds a quantum film to the LCD backlight module, QDCF technology directly converts a standard LCD color filter (color filter) material into QDs (quantum dots) to represent a desired color. Recently, samsung proposed a new technology of combining quantum dots with OLEDs, applying the blue light of the OLEDs to a backlight module, and allowing the light to be full-colored through red and green color filters composed of quantum dots. The use of color filters is similar to LCDs, while the use of OLED materials, rather than liquid crystals, is similar to OLEDs and is therefore called the OLED quantum dot hybrid technology. Because the material of backlight unit is OLED and does not contain the liquid crystal material, can realize flexible display technique in theory.

Because the QD layer contains scattering particles, the QD layer can be approximately regarded as a lambertian body after QD, and the distribution of the lambertian body is almost the same in all directions, so that except for the light emission of the forward hemisphere, the light of the residual reverse hemisphere is confined in the device, thereby influencing the whole conversion efficiency.

Disclosure of Invention

In view of the above-mentioned drawbacks or deficiencies in the prior art, it is desirable to provide a QD display structure and display device.

In a first aspect, a QD display structure is provided, which includes a first substrate and a second substrate that are oppositely disposed, wherein a color film layer is disposed on one side of the first substrate close to the second substrate, and a quantum dot layer is formed on one side of the color film layer close to the second substrate;

one side of the second substrate, which is close to the first substrate, is provided with a blue EL layer, the blue EL layer is provided with a cathode layer, and the material of the cathode layer has negative dielectric constant performance.

In a second aspect, a QD display structure is provided, which includes a first substrate and a second substrate that are disposed oppositely, a color film layer is disposed on one side of the first substrate close to the second substrate, and a quantum dot layer is formed on one side of the color film layer close to the second substrate;

a blue EL layer is arranged on one side, close to the first substrate, of the second substrate, a cathode layer is arranged on the blue EL layer, a TFE film layer is further arranged on the cathode layer, a plurality of microstructures are arranged on the TFE film layer, a composite material grows on each microstructure, and the composite material grows along the microstructures; the composite material has negative dielectric constant performance.

In a third aspect, there is provided a display device comprising the above-described QD display structure,

the color film layer comprises blue sub-pixels, red sub-pixels and green sub-pixels which are distributed in an array mode, the quantum dot layer comprises green quantum dots and red quantum dots, the green quantum dots are arranged corresponding to the green sub-pixels, the red quantum dots are arranged corresponding to the red sub-pixels, and a light shielding layer is arranged among the adjacent blue sub-pixels, the red sub-pixels and the green sub-pixels.

According to the technical scheme provided by the embodiment of the application, the material with the negative dielectric constant is provided, the cathode layer with the negative dielectric constant or the microstructure is arranged, the material with the negative dielectric constant performance grows on the cathode layer, the material has the characteristics of small-angle light penetration and large-angle light reflection, secondary emergence is carried out on red and green light of a lower hemisphere scattered by the QD layer, and meanwhile, secondary absorption is carried out on the scattered blue light, so that the QD conversion efficiency is improved.

Drawings

Other features, objects and advantages of the present application will become more apparent upon reading of the following detailed description of non-limiting embodiments thereof, made with reference to the accompanying drawings in which:

FIG. 1 is a schematic diagram of a QD display structure in an embodiment;

FIG. 2 is a schematic diagram of another embodiment of a QD display structure;

FIG. 3 is a graph showing the relationship between the light angle and the reflectance for different materials of the cathode layer.

Detailed Description

The present application will be described in further detail with reference to the following drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the relevant invention and not restrictive of the invention. It should be noted that, for convenience of description, only the portions related to the present invention are shown in the drawings.

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present application will be described in detail below with reference to the embodiments with reference to the attached drawings.

Referring to fig. 1, the present embodiment provides a QD display structure, including a first substrate 1 and a second substrate 11 that are disposed opposite to each other, wherein a color film layer 2 is disposed on a side of the first substrate 1 close to the second substrate 11, and a quantum dot layer 3 is formed on a side of the color film layer 2 close to the second substrate 11;

one side of the second substrate 11, which is close to the first substrate 1, is provided with a blue EL layer 9, the blue EL layer 9 is provided with a cathode layer 81, and the cathode layer 81 is made of a negative dielectric constant material.

The QD that this embodiment provided shows the structure and has set up the cathode layer on blue EL layer, this cathode layer is the negative dielectric constant performance, can be greater than the light bulk reflection of 30 jiaos through this electrode, the light that is less than 30 jiaos sees through, the blue light that sends as blue EL layer is through the quantum dot layer, by the quantum dot scattering of quantum dot layer, the red green light of quantum dot layer episphere can see through the various rete and launch away, the red green light of lower hemisphere can be reflected by the cathode layer part, launch away through quantum dot layer and various rete again, and simultaneously, the blue light that is scattered by the quantum dot layer can twice pass through the quantum dot layer, carry out secondary absorption and conversion, launch away at last, so can improve the conversion efficiency of this QD display structure.

Further, the cathode layer 81 is evaporated on the blue EL layer 9, and the cathode layer 81 includes a negative dielectric constant metal and silver, and a thickness ratio of the negative dielectric constant metal to the silver is 5nm to 5nm, or 5nm to 10 nm.

The cathode layer in the embodiment is arranged in an evaporation mode, two metals are adopted for evaporation, the two metals are evaporated together to form the cathode layer, and the evaporation thickness of each metal is controlled by controlling the evaporation speed of each metal; in this embodiment, the cathode layer is preferably prepared by using the metal calcium and the metal silver, as shown in fig. 3, a relation graph of light angles and reflectivities of different materials of the cathode layer is shown, the abscissa is light at different angles, and the ordinate is the reflectivities of the material, the graph shows that six kinds of metal calcium and metal silver with different thicknesses are compounded to prepare the cathode layer, and the reflectivities of the materials at different light angles need to be provided according to the proportion of non-reflection at small angles and reflection at large angles, so that the cathode layer is preferably prepared by using the thickness ratio of 5nm to 5nm or 5nm to 10 nm.

Further, the negative dielectric constant metal is calcium or magnesium or lithium or sodium. In this embodiment, the cathode layer is prepared by using a metal with a negative dielectric constant, which may be, but not limited to, calcium or magnesium or lithium or sodium.

The QD display structure in this embodiment includes a first substrate 1 and a second substrate 11 that are oppositely disposed, an anode layer 10 is disposed on the second substrate 11, a blue EL layer 9 is prepared on the anode layer 10, a cathode layer 81 is prepared on the blue EL layer 9 by evaporation, the cathode layer 81 has a characteristic of negative dielectric constant, a color film layer 2 is prepared on the first substrate 1, the color film layer 2 includes blue sub-pixels 22, red sub-pixels 21 and green sub-pixels 23 that are distributed in an array, a quantum dot layer 3 is prepared on the color film layer 2, the quantum dot layer 3 can be prepared by photolithography or printing, the quantum dot layer 3 includes green quantum dots 32 and red quantum dots 31, the green quantum dots 32 are disposed corresponding to the green sub-pixels 23, the red quantum dots 31 are disposed corresponding to the red sub-pixels 21, and are adjacent to the blue sub-pixels 22, A light-shielding layer is arranged between the red sub-pixel 21 and the green sub-pixel 23;

the side of the quantum dot 3 layer close to the second substrate 11 is provided with a barrier layer 4, and the barrier layer 4 covers the light shielding structure and the quantum dot layer 3.

Referring to fig. 2, the present embodiment provides a QD display structure, including a first substrate 1 and a second substrate 11 that are disposed opposite to each other, wherein a color film layer 2 is disposed on a side of the first substrate 1 close to the second substrate 11, and a quantum dot layer 3 is formed on a side of the color film layer 2 close to the second substrate 11;

a blue EL layer 9 is arranged on one side, close to the first substrate 1, of the second substrate 11, a cathode layer 82 is arranged on the blue EL layer 9, a TFE film layer 7 is further arranged on the cathode layer 82, a plurality of microstructures 6 are arranged on the TFE film layer 7, a composite material 5 grows on each microstructure 6, and the composite material 5 grows along the microstructures 6; the composite material 5 has a negative dielectric constant property.

The QD display structure provided in this embodiment sets up the TFE (tetrafluoroethylene resin) film layer on the cathode layer, set up the microstructure on the TFE film layer afterwards, grow the combined material on the microstructure, the combined material is the material of negative dielectric constant performance, the light greater than 30 ° angle is reflected greatly through this combined material, the light less than 30 ° angle permeates, when the blue light that blue EL layer sent is through the quantum dot layer, it is, by the quantum dot scattering of quantum dot layer, the red green light of quantum dot layer hemisphere can permeate the color film layer and emit, the red green light of lower hemisphere can be reflected by the cathode layer part, pass through quantum dot layer and color film layer and emit, simultaneously, the blue light that is scattered by the quantum dot layer can pass through the quantum dot layer twice, carry out secondary absorption and conversion, finally emit, so can improve the conversion efficiency of this QD display structure.

Further, each of the microstructures 6 includes a plurality of grooves, the color film layer 2 includes blue sub-pixels 22, red sub-pixels 21 and green sub-pixels 23 distributed in an array, and each of the green sub-pixels 23 and the red sub-pixels 21 is provided with one of the microstructures 6 correspondingly.

The microstructure provided by the embodiment is provided with a plurality of grooves, and secondary emergence is performed on red and green light of the lower hemisphere scattered by the quantum dot layer through the groove structure, wherein the red light and the green light are mainly subjected to secondary emergence, so that the microstructure only needs to be arranged at the position corresponding to each green sub-pixel and each red sub-pixel, and a composite material correspondingly grows on the microstructure; the size of the micro structure is the same as that of each green quantum dot structure or each red quantum dot structure, namely secondary emergence of red and green light can be achieved, meanwhile, the number of the protrusions and the number of the grooves of the micro structure can not be limited, the more the number of the grooves is, the better the secondary emergence effect of the red and green light is, three grooves are formed in the micro structure shown in figure 2, the more the grooves are, the better the effect is, but the process difficulty can be correspondingly increased, and the micro structure can be prepared according to actual conditions.

Further, the composite material 5 is a graphene and phenolic resin composite material, and the mass ratio of the graphene to the phenolic resin is (0.25-0.5): 1.

In this embodiment, a graphene and phenolic resin composite material is adopted to grow on a microstructure, and at this time, the composite material has a negative dielectric constant characteristic, and has characteristics of large-angle reflection and small-angle penetration of light irradiated on the composite material, wherein a preferable mass ratio of the graphene to the phenolic resin is 0.33: 1.

Further, the composite material 5 is evaporated or sputtered on the microstructure 6. In this embodiment, the composite material is grown on the microstructure, and may be specifically prepared by evaporation or sputtering.

Further, the microstructure 6 is disposed on the TFE film layer 7 by photolithography or nanoimprint or transfer printing.

Set up the microstructure in this embodiment on the TFE rete, protect the material on EL layer through this TFE rete, carry out the preparation of microstructure on the TFE rete afterwards, it is specific can adopt photoetching or nano-imprint's mode to go on, can not cause the damage to the surface of TFE rete, or can also advance the film including the microstructure, the mode of rethread transfer-printing is transferred to on the TFE rete, or directly attached on the TFE rete with the film that has set up the microstructure, specific technology can select according to actual conditions.

The QD display structure in this embodiment includes a first substrate 1 and a second substrate 11 which are oppositely disposed, an anode layer 10 is disposed on the second substrate 11, a blue EL layer 9 is prepared on the anode layer 10, and then a cathode layer 82 is prepared on the blue EL layer 9 by evaporation, where the cathode layer 82 may be a conventional cathode layer, for example, a magnesium silver material is prepared for the cathode layer; preparing a TFE film layer 7 on the cathode layer 82, preparing a layer of microstructure 6 after preparing the TFE film layer 7, arranging the microstructure 6, the red sub-pixel 21 and the green sub-pixel 23 in a one-to-one correspondence mode, and evaporating or sputtering the composite material 5 on the microstructure 6;

preparing a color film layer 2 on a first substrate 1, wherein the color film layer 2 comprises blue sub-pixels 22, red sub-pixels 21 and green sub-pixels 23 which are distributed in an array manner, preparing a quantum dot layer 3 on the color film layer 2, the quantum dot layer 3 can be prepared in a photoetching or printing manner, the quantum dot layer 3 comprises green quantum dots 32 and red quantum dots 31, the green quantum dots 32 are arranged corresponding to the green sub-pixels 23, the red quantum dots 31 are arranged corresponding to the red sub-pixels 21, and a light shielding layer is arranged between the adjacent blue sub-pixels 22, the adjacent red sub-pixels 21 and the adjacent green sub-pixels 23; when the blue light passes through the red quantum dots and the green quantum dots, the blue and green light is scattered by the red and green quantum dots, the red and green light of the upper hemisphere can be emitted through the color film layer, the red and green light of the lower hemisphere can be partially reflected and then passes through the red and green quantum dots again to be emitted through the color film layer, and when the blue light scattered by the red and green quantum dots is reflected, the blue light can pass through the quantum dot layer for the second time, is absorbed for the second time and then is converted, and finally is emitted, so that the conversion efficiency is improved.

A barrier layer 4 is disposed on the side of the quantum dot layer 3 close to the second substrate 11, and the barrier layer 4 covers the light shielding structure and the quantum dot layer 3.

The embodiment also provides a display device, which comprises the QD display structure.

The above description is only a preferred embodiment of the application and is illustrative of the principles of the technology employed. It will be appreciated by a person skilled in the art that the scope of the invention as referred to in the present application is not limited to the embodiments with a specific combination of the above-mentioned features, but also covers other embodiments with any combination of the above-mentioned features or their equivalents without departing from the inventive concept. For example, the above features may be replaced with (but not limited to) features having similar functions disclosed in the present application.

Claims

1. A quantum dot display structure is characterized by comprising a first substrate and a second substrate which are oppositely arranged, wherein a color film layer is arranged on one side of the first substrate close to the second substrate, and a quantum dot layer is formed on one side of the color film layer close to the second substrate;

a blue EL layer is arranged on one side, close to the first substrate, of the second substrate, a cathode layer is arranged on the blue EL layer, a TFE film layer is further arranged on the cathode layer, a plurality of microstructures are arranged on the TFE film layer, a composite material grows on each microstructure, and the composite material grows along the microstructures; the composite material has negative dielectric constant performance;

each microstructure comprises a plurality of grooves, the color film layer comprises blue sub-pixels, red sub-pixels and green sub-pixels which are distributed in an array mode, and each green sub-pixel and each red sub-pixel are correspondingly provided with one microstructure.

2. The quantum dot display structure according to claim 1, wherein the composite material is a graphene and phenolic resin composite material, and the mass ratio of the graphene to the phenolic resin is (0.25-0.5): 1.

3. The quantum dot display structure of claim 1, wherein the composite material is evaporated or sputtered on the microstructure.

4. The quantum dot display structure of claim 1, wherein the microstructures are disposed on the TFE film layer by photolithography or nanoimprinting or transfer printing.

5. A display device comprising the quantum dot display structure according to any one of claims 1 to 4,

the color film layer comprises blue sub-pixels, red sub-pixels and green sub-pixels which are distributed in an array mode, the quantum dot layer comprises green quantum dots and red quantum dots, the green quantum dots are arranged corresponding to the green sub-pixels, the red quantum dots are arranged corresponding to the red sub-pixels, and a light shielding layer is arranged between the adjacent blue sub-pixels, the adjacent red sub-pixels and the adjacent green sub-pixels.

6. The display device according to claim 5, wherein a barrier layer is provided on a side of the quantum dot layer adjacent to the second substrate, and an anode layer is further provided between the second substrate and the blue EL layer.