CN111509027B - QD display structure and display device - Google Patents

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 generally relates to the field of display technology, and in particular, to a QD display structure and a display device.

Background technique

At present, the application of quantum dots in the field of display technology is roughly divided into two categories: electroluminescence and photoluminescence, mainly including the following three applications: (1) Quantum dot backlight (QDEF) based on photoluminescence characteristics; (2) ) quantum dot dichroic filters (QDCF) based on photoluminescence properties; (3) quantum dot light emitting diodes (QD-LEDs) based on electroluminescence properties.

At present, products using quantum dot technology, such as Samsung SUHD TVs that have been on the market, mainly use QDEF technology. Colors are displayed by means of liquid crystals and color filters. Although the structure is the same as that of LCD, it can get quite good color reproduction effect through QDEF technology. Unlike QDEF, which adds quantum thin films to the LCD backlight module, QDCF technology directly replaces the standard LCD color filter material with QD (quantum dots) to express the desired color. Recently, Samsung proposed a new technology that combines quantum dots and OLEDs. The blue light of OLEDs is applied to the backlight module, so that the light can pass through the red and green color filters composed of quantum dots to achieve full color. The use of color filters is similar to LCD, and at the same time, it does not use liquid crystal but OLED materials are similar to OLED, so it is called OLED quantum dot hybrid technology. Since the material of the backlight module is OLED and does not contain liquid crystal material, it is theoretically possible to realize flexible display technology.

Since the QD layer contains scattering particles, it can be approximately regarded as a Lambertian after the QD, and the distribution of the Lambertian is almost the same in all directions, so in addition to the light emission of the forward hemisphere, the light of the remaining reverse hemisphere is Being confined in the device affects the overall conversion efficiency.

SUMMARY OF THE INVENTION

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

In a first aspect, a QD display structure is provided, comprising a first substrate and a second substrate arranged opposite to each other, a color filter layer is provided on the side of the first substrate close to the second substrate, and the color filter layer is close to the second substrate. A quantum dot layer is formed on one side of the second substrate;

A blue EL layer is arranged on the side of the second substrate close to the first substrate, a cathode layer is arranged on the blue EL layer, and the material of the cathode layer has negative dielectric constant properties.

In a second aspect, a QD display structure is provided, comprising a first substrate and a second substrate disposed opposite to each other, a color filter layer is provided on the side of the first substrate close to the second substrate, and the color filter layer is close to the second substrate. A quantum dot layer is formed on one side of the second substrate;

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

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

The color filter layer includes blue sub-pixels, red sub-pixels and green sub-pixels distributed in an array, the quantum dot layer includes green quantum dots and red quantum dots, and 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 provided between the adjacent blue sub-pixels, red sub-pixels and green sub-pixels.

According to the technical solutions provided in the embodiments of the present application, by providing a material with a negative permittivity, it can be a cathode layer with a negative permittivity or a microstructure on which a material with negative permittivity properties is grown, and the material has a small angle The characteristics of large-angle light reflection through light passing through, secondary emission of red and green light in the lower hemisphere scattered by the QD layer, and secondary absorption of the scattered blue light to improve the QD conversion efficiency.

Description of drawings

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

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

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

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

Detailed ways

The present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the related invention, but not to limit the invention. In addition, it should be noted that, for the convenience of description, only the parts related to the invention are shown in the drawings.

It should be noted that the embodiments in the present application and the features of the embodiments may be combined with each other in the case of no conflict. The present application will be described in detail below with reference to the accompanying drawings and in conjunction with the embodiments.

Referring to FIG. 1 , this embodiment provides a QD display structure, including a first substrate 1 and a second substrate 11 disposed opposite to each other, and a color filter layer is provided on the side of the first substrate 1 close to the second substrate 11 . 2. A quantum dot layer 3 is formed on the side of the color filter layer 2 close to the second substrate 11;

A blue EL layer 9 is formed on the side of the second substrate 11 close to the first substrate 1 , a cathode layer 81 is formed on the blue EL layer 9 , and the material of the cathode layer 81 is of negative dielectric constant performance .

The QD display structure provided in this embodiment is provided with a cathode layer on the blue EL layer. The cathode layer has negative dielectric constant performance, and can reflect a large amount of light at an angle greater than 30° through the electrode, and light at an angle less than 30° can be reflected through the electrode. Through, when the blue light emitted by the blue EL layer passes through the quantum dot layer, it is scattered by the quantum dots in the quantum dot layer, the red and green light in the upper hemisphere of the quantum dot layer can be emitted through the color filter layer, and the red and green light in the lower hemisphere It can be partially reflected by the cathode layer, and then emitted through the quantum dot layer and the color filter layer. At the same time, the blue light scattered by the quantum dot layer can pass through the quantum dot layer twice, undergo secondary absorption and conversion, and finally be emitted, which can improve the This QD shows the conversion efficiency of the 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 the thickness ratio of the negative dielectric constant metal and silver is 5nm:5nm , or 5nm:10nm.

The cathode layer in this embodiment is set by means of evaporation, and two metals are used for evaporation, and the two metals are co-evaporated to form a cathode layer, and the evaporation thickness of each metal is controlled by controlling the evaporation speed of various metals; In this embodiment, metal calcium and metal silver are preferably used to prepare the cathode layer. As shown in FIG. 3, the relationship between light angle and reflectivity under different materials of the cathode layer is shown. The abscissa is the light at different angles, and the ordinate is the material. The reflectivity of six different thicknesses of metal calcium and metal silver is shown in the figure to prepare the cathode layer. The reflectivity of each material under different light angles needs to be provided in this application. Therefore, it is preferable to use a thickness ratio of 5nm:5nm, or 5nm:10nm to prepare the cathode layer.

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

The QD display structure in this embodiment includes a first substrate 1 and a second substrate 11 that are opposite to each other, an anode layer 10 is provided on the second substrate 11, a blue EL layer 9 is prepared on the anode layer 10, and then a blue EL layer is formed on the blue EL layer. 9, the cathode layer 81 is prepared by vapor deposition. The cathode layer 81 is characterized by a negative dielectric constant. At the same time, a color filter layer 2 is prepared on the first substrate 1. Pixel 22, red sub-pixel 21 and green sub-pixel 23, a quantum dot layer 3 is prepared on the color filter layer 2, the quantum dot layer 3 can be prepared by photolithography or printing, and the quantum dot layer 3 includes green quantum dots. 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, adjacent to the blue sub-pixels 22, A light shielding layer is provided between the red sub-pixel 21 and the green sub-pixel 23;

A barrier layer 4 is provided 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 .

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

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

In the QD display structure provided in this embodiment, a TFE (tetrafluoroethylene resin) film layer is arranged on the cathode layer, and then a microstructure is arranged on the TFE film layer, and a composite material is grown on the microstructure, and the composite material has a negative dielectric constant property. Through the composite material, a large amount of light with an angle greater than 30° is reflected, and light with an angle less than 30° is transmitted. When the blue light emitted by the blue EL layer passes through the quantum dot layer, it is scattered by the quantum dots of the quantum dot layer, and the quantum The red and green light in the upper hemisphere of the dot layer can be emitted through the color filter layer, and the red and green light in the lower hemisphere can be partially reflected by the cathode layer, and then emitted through the quantum dot layer and the color filter layer. The blue light can pass through the quantum dot layer twice, undergo secondary absorption and conversion, and finally be emitted, which can improve the conversion efficiency of the QD display structure.

Further, each of the microstructures 6 includes a plurality of grooves, the color filter 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 Each of the red sub-pixels 21 is provided with one of the microstructures 6 .

The microstructure provided in this embodiment is provided with a plurality of grooves, and the red and green light in the lower hemisphere scattered by the quantum dot layer is re-emitted through the groove structure. , it is only necessary to set a microstructure at the corresponding position of each green sub-pixel and red sub-pixel, and the composite material is grown on the microstructure accordingly; the size of the microstructure is set to the same as that of each green quantum dot structure or red quantum dot. The size of the structure is the same, that is, the secondary emission of red and green light can be realized. At the same time, the number of protrusions and grooves set by the microstructure can be unlimited. The better the effect of the secondary shot is, the microstructure shown in Figure 2 is provided with three grooves. The more grooves, the better the effect, but the difficulty of the process will increase accordingly, which can be prepared according to the actual situation.

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

In this embodiment, graphene and phenolic resin composite materials are used to grow on the microstructure. At this time, the composite material has negative dielectric constant characteristics, and the light irradiated on the composite material has the characteristics of large-angle reflection and small-angle passing through. Wherein the preferred mass ratio of this graphene and phenolic resin is 0.33:1.

Further, the composite material 5 is evaporated or sputtered on the microstructure 6 . In this embodiment, the growth of the composite material is performed on the microstructure, which can be specifically prepared by evaporation or sputtering.

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

In this embodiment, a microstructure is arranged on the TFE film layer, the material of the EL layer is protected by the TFE film layer, and then the microstructure is prepared on the TFE film layer, specifically, photolithography or nano-imprinting can be used. It will not cause damage to the surface of the TFE film layer, or the film including the microstructure can be carried out first, and then transferred to the TFE film layer by transfer, or the film with the microstructure can be directly attached to the TFE. On the film layer, the specific process can be selected according to the actual situation.

The QD display structure in this embodiment includes a first substrate 1 and a second substrate 11 that are opposite to each other, an anode layer 10 is provided on the second substrate 11, a blue EL layer 9 is prepared on the anode layer 10, and then a blue EL layer is formed on the blue EL layer. 9, the cathode layer 82 is prepared by evaporation, and the cathode layer 82 can be a conventional cathode layer, such as magnesium-silver material to prepare the cathode layer; then the TFE film layer 7 is prepared on the cathode layer 82, and the TFE film is After the layer 7 is prepared, a layer of microstructure 6 is made, and the microstructure 6 is arranged in a one-to-one correspondence with the red sub-pixel 21 and the green sub-pixel 23, and the above-mentioned composite material 5 is evaporated or sputtered on the microstructure 6;

At the same time, a color filter layer 2 is prepared on the first substrate 1, the color filter layer 2 includes blue sub-pixels 22, red sub-pixels 21 and green sub-pixels 23 distributed in an array, and a quantum dot layer 3 is prepared on the color filter 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 arranged corresponding to the green sub-pixels 23, so 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, red sub-pixels 21 and green sub-pixels 23; When the light is on, it is scattered by the red and green quantum dots, the red and green light in the upper hemisphere can be emitted through the color filter layer, and the red and green light in the lower hemisphere can be partially reflected and then pass through the red and green quantum dots and then be emitted through the color filter layer. When the blue light scattered by the red and green quantum dots is reflected, it can pass through the quantum dot layer twice, be absorbed and converted twice, and finally emitted to improve the conversion efficiency.

A barrier layer 4 is provided 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 .

This embodiment also provides a display device including the above-mentioned QD display structure.

The above description is only a preferred embodiment of the present application and an illustration of the applied technical principles. Those skilled in the art should understand that the scope of the invention involved in this application is not limited to the technical solution formed by the specific combination of the above-mentioned technical features, and should also cover the above-mentioned technical features without departing from the inventive concept. Other technical solutions formed by any combination of its equivalent features. For example, a technical solution is formed by replacing the above-mentioned features with the technical features disclosed in this application (but not limited to) with similar functions.

Claims (6)

1. A quantum dot display structure, characterized in that it comprises a first substrate and a second substrate that are oppositely arranged, a side of the first substrate close to the second substrate is provided with a color filter layer, and the color filter layer is A quantum dot layer is formed on one side close to the second substrate; A blue EL layer is arranged on the side of the second substrate close to the first substrate, a cathode layer is arranged on the blue EL layer, a TFE film layer is also arranged on the cathode layer, and the TFE film layer is arranged on the blue EL layer. A plurality of microstructures are arranged thereon, and a composite material is grown on each of the microstructures, and the composite material grows along the microstructure; the composite material has negative dielectric constant performance; Each of the microstructures includes a plurality of grooves, the color filter layer includes blue sub-pixels, red sub-pixels and green sub-pixels distributed in an array, and each of the green sub-pixels and the red sub-pixels is correspondingly arranged There is one such 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 . 3 . The quantum dot display structure according to claim 1 , wherein the composite material is evaporated or sputtered on the microstructure. 4 . 4 . The quantum dot display structure according to claim 1 , wherein the microstructure is arranged on the TFE film layer by means of photolithography, nanoimprinting or transfer printing. 5 . 5. A display device, characterized in that, comprising the quantum dot display structure according to any one of claims 1-4, The color filter layer includes blue sub-pixels, red sub-pixels and green sub-pixels distributed in an array, the quantum dot layer includes green quantum dots and red quantum dots, and 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 provided between the adjacent blue sub-pixels, red sub-pixels and 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 close to the second substrate, and a barrier layer is provided between the second substrate and the blue EL layer. 7 . An anode layer is provided.

Images