WO2021051787A1

WO2021051787A1 - Display device and backlight module

Info

Publication number: WO2021051787A1
Application number: PCT/CN2020/083856
Authority: WO
Inventors: 李富琳
Original assignee: 海信视像科技股份有限公司
Priority date: 2019-09-20
Filing date: 2020-04-09
Publication date: 2021-03-25
Also published as: CN113625489A; CN110456574A; CN113625489B

Abstract

A display device and a backlight module (10), comprising a circuit board (101), multiple miniature light-emitting diodes (102) provided on the circuit board (101), a protective plastic layer (103) covering the multiple miniature light-emitting diodes (102) and the circuit board (101), a transparent substrate (104) provided on the side of the protective plastic layer (103) facing away from the circuit board (101), and a diffusing plate (105) provided on the side of the transparent substrate (104) facing away from the circuit board (101), where the thickness of the transparent substrate (104) satisfies a light mixing distance of the miniature light-emitting diodes (102). With the transparent substrate (104) serving as a supporting structure between the protective plastic layer (103) and the diffusing plate (105), lights emitted by the miniature light-emitting diodes (102) are fully mixed before reaching the diffusing plate (105), thus increasing a backlight illumination effect.

Description

Display device and backlight module

Cross-reference to related applications

This application claims the priority of a Chinese patent application filed with the Chinese Patent Office on September 20, 2019, the application number is 201910891020.5, and the invention title is "a display device and backlight module", the entire content of which is incorporated into this application by reference in.

Technical field

This application relates to the field of liquid crystal display, and in particular to a display device and a backlight module.

Background technique

High-Dynamic Range (HDR) technology can provide more dynamic performance and image details, can better reflect the visual effects of objects in the real environment, and is generally considered to cause display The next change in the field. At the same time, HDR technology also puts forward higher requirements for liquid crystal display terminals-finer zone control and contrast.

The size of a mini LED is about 50μm-300μm. Using a huge number of mini LED dies as the backlight source and applied to the liquid crystal display field can not only realize the thinning of the backlight module, but also realize more refined dynamic control and improve the dynamic contrast of the liquid crystal display.

In the traditional direct-lit backlight module, a diffuser support is usually placed between the light board and the diffuser to complete light mixing. However, the LED spacing of the mini LED light board is very small, generally less than 5mm, which is not enough to place the diffuser support, so it is difficult to achieve conventional methods.

Summary of the invention

The application provides a display device and a backlight module for optimizing the light mixing effect.

In a first aspect of the embodiments of the present application, a display device is provided, including: a backlight module and a display panel located on the light emitting side of the backlight module;

The backlight module includes: a circuit board, a plurality of micro light emitting diodes arranged on the circuit board, covering the plurality of micro light emitting diodes and a protective glue layer of the circuit board, arranged on the protective glue layer away from A transparent substrate on one side of the circuit board, and a diffuser plate disposed on the side of the transparent substrate away from the circuit board;

Wherein, the thickness of the transparent substrate satisfies the light mixing distance of the micro light emitting diode.

In some embodiments, in the above-mentioned display device provided in the present application, the surface of the transparent substrate facing the protective adhesive layer is an uneven surface.

In some embodiments, in the above-mentioned display device provided in the present application, the uneven surface has a plurality of strip-shaped concave-convex edges arranged in parallel.

In some embodiments, in the above-mentioned display device provided in the present application, the surface of the transparent substrate facing the protective glue layer is coated with a scattering coating, and the scattering coating includes a colloidal layer and a colloidal layer. Of scattering particles.

In some embodiments, in the above-mentioned display device provided by the present application, a bonding adhesive layer is further included between the transparent substrate and the protective adhesive layer, and the bonding adhesive layer is in contact with the transparent substrate and the protective adhesive layer. There is no gap between the protective glue layers.

In some embodiments, in the above-mentioned display device provided by the present application, the backlight module further includes an optical film group disposed on a side of the diffusion sheet away from the transparent substrate.

In some embodiments, in the above-mentioned display device provided by the present application, the size of the micro light-emitting diode is 50 μm-300 μm.

In some embodiments, in the above-mentioned display device provided in the present application, the material of the protective glue layer is silica gel or epoxy resin.

In some embodiments, in the above-mentioned display device provided in the present application, the material of the transparent substrate is polymethyl methacrylate or polycarbonate.

In the first aspect of the embodiments of the present application, a backlight module is provided. It includes a circuit board, a plurality of micro light emitting diodes arranged on the circuit board, a protective glue layer covering the plurality of micro light emitting diodes and the circuit board, and arranged on a side of the protective glue layer away from the circuit board A transparent substrate of, and a diffuser plate disposed on the side of the transparent substrate away from the circuit board;

The beneficial effects of this application are as follows:

The display device and the backlight module provided by the present application include a circuit board, a plurality of micro light emitting diodes arranged on the circuit board, covering the plurality of micro light emitting diodes and a protective glue layer of the circuit board, and arranged on the circuit board. The protective adhesive layer has a transparent substrate on the side facing away from the circuit board, and a diffuser plate arranged on the side of the transparent substrate facing away from the circuit board; wherein the thickness of the transparent substrate meets the light mixing ratio of the micro light emitting diode distance. The transparent substrate is used as the supporting structure between the protective glue layer and the diffuser, so that the light emitted by the micro light emitting diode can be fully mixed before reaching the diffuser, and the light mixing effect is optimized.

Description of the drawings

FIG. 1 is one of the schematic structural diagrams of a display device provided by an embodiment of the application;

2 is a schematic diagram of the optical path of a transparent substrate provided by an embodiment of the application;

FIG. 3 is the second structural diagram of the display device provided by the embodiment of the application;

4 is the third structural diagram of the display device provided by the embodiment of the application;

5 is a schematic diagram of the structure of a transparent substrate provided by an embodiment of the application;

FIG. 6 is the fourth structural diagram of the display device provided by the embodiment of the application;

FIG. 7 is a schematic diagram of the structure of a scattering coating provided by an embodiment of the application;

FIG. 8 is the fifth schematic diagram of the structure of the display device provided by the embodiment of the present application;

FIG. 9 is a sixth structural diagram of the display device provided by the embodiment of the present application;

FIG. 10 is the seventh structural diagram of the display device provided by the embodiment of the present application;

FIG. 11 is a schematic structural diagram of a backlight module provided by an embodiment of the application.

detailed description

In order to make the purpose, technical solutions, and advantages of the application more clear, the application will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the application, rather than all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of this application.

In the first aspect of the embodiments of the present application, a display device is provided. As shown in FIG. 1, the display device includes a backlight module 10 and a display panel 20 located on the light emitting side of the backlight module 10.

The display panel 20 is located on the light emitting side of the backlight module 10. It has a plurality of pixel units arranged in an array, and each pixel unit can independently control the light transmittance and color of the backlight module 10 incident on the pixel unit, so that the light transmitted by all the pixel units constitutes the display to be displayed Image.

The backlight module 10 can uniformly emit light in the entire light-emitting surface, and is used to provide the display panel 20 with light with sufficient brightness and uniform distribution, so that the display panel 20 can display images normally.

Specifically, the backlight module 10 includes: a circuit board 101, a plurality of micro light emitting diodes 102 arranged on the circuit board 101, a protective glue layer 103 covering the plurality of micro light emitting diodes 102 and the circuit board 101, arranged on the protective glue layer 103 The transparent substrate 104 on the side facing away from the circuit board 101 and the diffuser 105 disposed on the side of the transparent substrate 104 facing away from the circuit board 101.

Among them, the circuit board 101 is used to provide driving electrical signals for the micro light emitting diodes. The circuit board 101 is provided with solder feet and circuit lines. The electrodes of the micro light emitting diode 102 are welded to the solder feet of the circuit board 101 through a welding process. The circuit lines are used to electrically connect the micro light emitting diodes 102 to each other and the micro light emitting diodes. 102 is electrically connected to an external power drive board (not shown in the figure).

In some embodiments of the present application, the circuit board 101 is a printed circuit board (Printed Circuit Board, PCB for short). The PCB includes an electronic circuit and an insulating layer. The insulating layer exposes the solder pins of the electronic circuit for welding the miniature light-emitting diode 102 to the outside. Cover the rest.

In some embodiments of the present application, the circuit board 101 is an array substrate formed by arranging a thin film transistor driving circuit on a base substrate. The surface of the array substrate has connection electrodes connected to the thin film transistor driving circuit, and the electrodes of each micro light emitting diode 102 Weld in one-to-one correspondence with each connecting electrode.

The substrate or base substrate of the above circuit board 101 can be made of flexible materials to form a flexible display device.

In the embodiment of the present application, the circuit board 101 is plate-shaped, and the whole is rectangular or square. The length of the circuit board 101 is 200-800mm, and the width is 100-500mm. According to the size of the display device, in the embodiment of the present application, the display device may include a plurality of circuit boards 101, and the circuit boards 101 are spliced together to form a light board structure. In order to avoid the optical problems caused by the splicing of the circuit boards 101, the seams between adjacent circuit boards 101 should be as small as possible, and even seamless splicing can be realized.

A plurality of miniature light emitting diodes 102 are used to emit light from the light source. The micro light emitting diodes are fixed on one side surface of the circuit board 101 by welding, and a plurality of micro light emitting diodes 102 are arranged in rows or columns, and the distance between two adjacent micro light emitting diodes 102 is less than 5 mm.

The size of the miniature light-emitting diode in the embodiment of the present application is about 50 μm-300 μm. The micro light emitting diode 101 is different from ordinary light emitting diodes, and specifically refers to a micro light emitting diode chip. The small size of the light-emitting chip is conducive to controlling the dynamic light emission to a smaller partition, and further improving the contrast of the picture. In the embodiment of the present application, the micro light emitting diode 102 is a monochromatic micro light emitting diode.

The protective glue layer 103 functions to encapsulate the micro light emitting diode 102, thereby effectively preventing the occurrence of unfavorable conditions such as falling off and moisture of the micro light emitting diode. The material used for the protective glue layer 103 includes silica gel or epoxy resin. It is also possible to use other materials whose light transmittance is close to the two. The protective glue layer 103 is formed by spraying.

In order to better protect the micro light emitting diode 102, the distance between the upper surface of the protective glue layer 103 and the upper surface of the micro light emitting diode 102 is 100-300 μm.

The transparent substrate 104 can transmit light from the micro light emitting diode 102 and is used to support the diffusion plate 105. The material of the transparent substrate 104 may be selected from at least one of polymethyl methacrylate or polycarbonate. However, it is not limited to this, and the transparent substrate 104 can also be made of other materials with high reflectivity and low absorbance. This is because light is reflected multiple times inside the transparent substrate 104. The use of materials with high reflectivity and low absorbance can minimize the attenuation of light as it propagates in the transparent substrate 104, thereby improving the light utilization rate of the backlight module. , Reduce power consumption. The transparent substrate 104 serves as a supporting structure of the diffuser plate 105, so that the light emitted by the micro light emitting diode 102 can be fully mixed before reaching the diffuser plate.

In the embodiment of the present application, the thickness of the transparent substrate 104 satisfies the light mixing distance of the micro light emitting diode 102, so that the light emitted by the micro light emitting diode can be fully mixed when reaching the diffuser 105 to ensure the backlight effect. In the embodiment of the present application, the thickness of the transparent substrate 104 is not greater than 10 mm.

The diffuser 105 continuously refracts and reflects light when passing through the diffuser, so as to achieve the effect of dispersing the light, thereby realizing the effect of uniform light. The material used for the diffusion plate is generally selected from at least one of polymethyl methacrylate PMMA, polycarbonate PC, polystyrene-based material PS, and polypropylene PP.

Moreover, the backlight module 10 does not have a diffuser support frame for supporting the diffuser 105 between the circuit board 101 and the diffuser 105.

The micro light emitting diode 102 is used as a point light source. Its emergent light type is in a cone shape, and the light intensity at the edge is less than the light intensity at the center. Therefore, it is necessary to mix the light in the edge area of two adjacent micro light emitting diodes to make the mixing. The difference between the light intensity of the light area and the light intensity of the central area is reduced. At present, the distance between the micro light emitting diodes 102 is very small, and it is not enough to place the diffuser support to complete the light mixing. Therefore, in the embodiment of the present application, the transparent substrate 104 is used to support the diffuser 105 so that the distance between the micro light emitting diode 102 and the diffuser 105 can be drawn. When the set distance is set, the thickness of the transparent substrate 104 meets the light mixing distance of the micro light emitting diode 102, so that the light emitted by the micro light emitting diode can be fully mixed when it reaches the diffuser 105, and the backlight effect is optimized.

In practical applications, the protective glue layer 103 covering the micro light emitting diode 102 has the function of encapsulating the micro light emitting diode 102. In the specific implementation, the micro light emitting diode can be packaged by glue dispensing, or the micro light emitting diode can be packaged by the whole layer coating method. The whole-layer coating packaging method has higher production efficiency and excellent effects. Since the protective glue layer 103 is usually formed on the micro light emitting diode by spraying, its surface is not flat, and it is easy to form protrusions or depressions in local areas. If there are protrusions on the surface of the protective adhesive layer 103 facing the transparent substrate, these protrusions are in contact with the transparent substrate 104, and the protective adhesive layer 103 and the transparent substrate 104 form an air layer in the area adjacent to the above-mentioned protrusions. Referring to the principle diagram of the optical path shown in FIG. 2, since the refractive index of air is less than that of the protective glue layer, some light in the transparent substrate 104 can be totally reflected when it enters the interface with the air layer, but at the same incident angle When light is incident on the interface with the protective glue layer, the critical angle increases due to the change of the total reflection conditions. The light that could have been totally reflected can exit from the interface, and the transparent substrate will exit at the convex portion. More light, resulting in bright bars.

In order to solve the above problems, as shown in FIG. 3, in the embodiment of the present application, the surface of the transparent substrate 104 facing the protective glue layer 103 is subjected to surface treatment, so that the surface becomes an uneven surface, thereby making the transparent substrate 104 and the protective adhesive layer 103 an uneven surface. A uniform dielectric layer is formed between the glue layers 103. Uniform here means that in terms of the lateral distribution of the dielectric layer, the distribution of the air dielectric layer or the protective glue layer is uniform, and there will be no large areas of the air dielectric layer or protective glue layer in a certain area. Therefore, the reflection of light at the interface is also uniform, thereby ensuring the uniformity of the emitted light and avoiding the occurrence of bright stripes. This application does not impose rigid requirements on the specific parameters of the above-mentioned uneven surface. Any uneven surface that can form a uniform dielectric layer between the transparent substrate 104 and the protective glue layer 103 is within the protection scope of this application.

In some embodiments, as shown in FIG. 4, in the display device provided by the embodiment of the present application, the surface of the transparent substrate 104 on the side close to the protective glue layer 103 has a plurality of strip-shaped concave-convex ridges arranged in parallel. The three-dimensional structure of the transparent substrate 104 is shown in FIG. 5. By appropriately setting the height of the bar-shaped concave-convex ridge and the angle between the slope included in the concave-convex ridge and the flat surface of the transparent substrate 104 away from the strip-shaped concave-convex ridge, the gap between the bar-shaped concave-convex ridge and the protective adhesive layer 103 , A uniform dielectric layer is formed to ensure that the backlight emits uniformly from the surface of the transparent substrate 104 away from the protective glue layer 103, avoiding the occurrence of bright stripes, and improving the uniformity of display brightness.

Wherein, the stripe uneven structure on the surface of the transparent substrate 104 in FIG. 4 can be formed by an etching process, a barrier material is provided on the surface of the transparent substrate 104, and an etching process is used to form the stripe uneven structure; or, it can also be formed on the transparent substrate 104 The surface of is covered with a film with a strip-shaped concave-convex structure; or a forming mold can be used to form a transparent substrate with a strip-shaped concave-convex ridge structure at one time. The height of the strip-shaped concave-convex ridge is about 20 μm-50 μm, and the apex angle is less than or equal to 90°. The transparent substrate 104 with this structure can form a uniform dielectric layer between the protective glue layer 103 and the transparent substrate 104.

In other embodiments, as shown in FIG. 6, the embodiment of the present application coats the scattering coating 106 on the surface of the transparent substrate 104 on the side close to the protective glue. The scattering coating 106 is uniformly coated on the surface of the transparent substrate 104, and the coating thickness is about 50 μm-200 μm. The scattering coating 106 is filled with some tiny solid particles, and light is scattered when incident on these particles, and the scattered light is uniformly emitted from the transparent substrate 104. The scattering coating 106 can be formed by sputtering, evaporation or other processes in the prior art.

Please refer to FIG. 7, which is a schematic diagram of the structure of the scattering coating provided by the embodiment of the present application. As shown in FIG. 7, the scattering coating 106 includes a colloidal layer 1061 and scattering particles 1062. Among them, the colloidal layer 1061 acts as a dispersant to uniformly disperse the scattering particles 1062 therein. The scattering particles 1062 are tiny particles, such as titanium dioxide and/or silica particles. After light is incident on the scattering particles 1062, it will propagate in all directions. Specifically, the material of the colloid layer may be a transparent resin, and its thickness should be as small as possible on the basis of ensuring that sufficient scattering particles are filled, so as to reduce the attenuation of the incident light energy by the scattering coating 106. When the transparent resin is in a liquid or colloidal state, the molecules have fluidity, so the scattering particles can be uniformly dispersed in it. After the scattering coating 106 is coated on the transparent substrate 104, the transparent resin can be cured by heating or lighting. When light enters the scattering coating 106 from the transparent substrate 104, uniform scattering can occur in each area of the scattering coating 106, so that it will not be affected by the convex portion of the protective glue layer 103. It is ensured that the light can be uniformly emitted from the side of the transparent substrate 104 away from the protective glue layer 103, avoiding the generation of bright stripes, and improving the uniformity of display brightness.

In some embodiments, as shown in FIG. 8, in the embodiment of the present application, an adhesive layer 107 is provided between the transparent substrate 104 and the protective adhesive layer 103, and the adhesive layer 107 is between the transparent substrate 104 and the protective adhesive layer 103. Fits without gaps. By setting the glue layer 107, only the uniform medium of the glue layer 107 exists between the transparent substrate 104 and the protective glue layer 103, so the total reflection conditions at all positions are the same when the light propagates in the transparent substrate. The problem of bright bars does not occur, thereby improving the uniformity of display brightness.

The bonding adhesive layer 107 may use ultraviolet curing adhesive. The UV-curing adhesive has a good light-transmitting type, and is usually in a colloidal shape. After filling the ultraviolet curing glue between the transparent substrate 104 and the protective glue layer 103, use ultraviolet rays to irradiate the layer of the transparent substrate 104 away from the protective glue layer 103 for 5-10 minutes to cure the glue, thereby making the transparent substrate 104 and the protective glue layer 103 are closely attached to each other.

In practical applications, as shown in FIG. 9, the backlight module 10 further includes an optical film group 108 disposed on the side of the diffuser 105 away from the transparent substrate 104.

Among them, the optical film set 108 may include one or more of prism films, quantum dot films, diffusers, reflective polarizers, etc. The purpose of adding these films to the backlight module 10 is to make the backlight module Group 10 is suitable for a variety of practical applications. For example, the prism sheet can change the exit angle of light, thereby changing the viewing angle of the display device. The quantum dot film can provide quantum dots with higher monochromaticity, which can be applied to quantum dot TVs to improve the display color gamut of TVs.

Exemplarily, please refer to FIG. 10, which is a schematic structural diagram of a display device provided in an embodiment of this application. In addition to the structure of the display device shown in FIG. 1, the display device is also provided with a quantum dot film 108' on the side of the diffuser plate 105 of the backlight module away from the transparent substrate 104, and the quantum dot film 108' is away from the diffuser plate 105. An optical film 108 such as a prism sheet and a composite film is provided. As shown in FIG. 10, the micro light emitting diode 102 is a blue light micro light emitting diode. After the blue light micro light emitting diode passes through a transparent substrate and a diffusion plate, a uniform surface light source is irradiated on the quantum dot film 108' to excite the quantum dot film 108' Glow. The quantum dot film 108' includes a red quantum dot material and a green quantum dot material. The red quantum dot material emits red light under the excitation of blue light, and the green quantum dot material emits green light under the excitation of blue light. Due to the limited luminous efficiency of the quantum dot material, the blue light will not be completely absorbed. By reasonably setting the ratio of the two quantum dot particles in the quantum dot film 108', the remaining blue light can be mixed with red light and green light into white light. Alternatively, other color schemes can also be used. For example, the microdiode 102 emits blue light and the quantum dot film is excited to emit yellow light. The blue light and yellow light can also be mixed into white light.

The second aspect of the embodiments of the present application provides a backlight module. Please refer to FIG. 11, which is a schematic structural diagram of a backlight module provided by an embodiment of this application. As shown in FIG. 11, the backlight module 10 includes a circuit board 101, a plurality of micro light emitting diodes 102 arranged on the circuit board 101, a protective glue layer 103 covering the plurality of micro light emitting diodes 102 and the circuit board 101, and is arranged on the protective glue The layer 103 is a transparent substrate 104 on the side facing away from the circuit board 101, and a diffuser 105 disposed on the transparent substrate 104 on a side facing away from the circuit board 101. Specifically, the backlight module may be a backlight module in any possible implementation of the above content, and each component contained therein has the same as each corresponding component of the backlight module in any possible implementation of the above content. Structure and function. For the sake of brevity of the description, it will not be repeated here. In this backlight module, the transparent substrate 104 is used as the supporting structure of the diffuser 105, and the surface of the transparent substrate 104 close to the protective glue layer 103 is in contact with a uniform medium, and the reflection of light on the surface is uniform. Therefore, the light emitted from the transparent substrate 104 is also uniform. Thus, the backlight module can provide uniform backlight illumination.

In summary, in the display device and the backlight module provided in the present application, each includes a circuit board 101, a plurality of micro light emitting diodes 102 arranged on the circuit board 101, and a circuit board 101 covering the plurality of micro light emitting diodes 102 and the circuit board 101. The protective glue layer 103 is disposed on the transparent substrate 104 on the side of the protective glue layer 103 away from the circuit board 101, and the diffuser 105 is disposed on the side of the transparent substrate 104 away from the circuit board 101. The transparent substrate 104 serves as a supporting structure between the protective glue layer 103 and the diffuser 105, so that the light emitted by the micro light emitting diode 102 can be fully mixed before reaching the diffuser. After the transparent substrate 104 is specially designed, the medium contacted by the surface close to the protective glue layer 103 is a uniform medium, and the reflection of light on the surface is uniform, so the light emitted from the transparent substrate 104 is also uniform. Finally, the display device can display images with uniform brightness, or the backlight module can provide backlight with uniform brightness.

Although the preferred embodiments of the present application have been described, those skilled in the art can make additional changes and modifications to these embodiments once they learn the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present application.

Obviously, those skilled in the art can make various changes and modifications to the application without departing from the spirit and scope of the application. In this way, if these modifications and variations of this application fall within the scope of the claims of this application and their equivalent technologies, this application is also intended to include these modifications and variations.

Claims

A display device, characterized by comprising: a backlight module and a display panel located on the light emitting side of the backlight module;

The backlight module includes: a circuit board, a plurality of micro light emitting diodes arranged on the circuit board, covering the plurality of micro light emitting diodes and a protective glue layer of the circuit board, arranged on the protective glue layer away from A transparent substrate on one side of the circuit board, and a diffuser plate disposed on the side of the transparent substrate away from the circuit board;

Wherein, the thickness of the transparent substrate satisfies the light mixing distance of the micro light emitting diode.
8. The display device of claim 1, wherein the surface of the transparent substrate facing the protective adhesive layer is an uneven surface.
3. The display device of claim 2, wherein the uneven surface has a plurality of strip-shaped concave-convex edges arranged in parallel.
The display device according to claim 1, wherein the surface of the transparent substrate facing the protective glue layer is coated with a scattering coating, and the scattering coating comprises a colloid layer and scattering layers distributed on the colloid layer. Particles.
The display device according to claim 1, characterized in that, between the transparent substrate and the protective glue layer further comprises a bonding glue layer, and the bonding glue layer is in contact with the transparent substrate and the protective glue layer. There is no gap between the layers.
8. The display device of claim 1, wherein the backlight module further comprises an optical film set disposed on a side of the diffusion sheet away from the transparent substrate.
The display device of claim 1, wherein the size of the micro light emitting diode is 50 μm-300 μm.
7. The display device according to any one of claims 1-7, wherein the material of the protective glue layer is silica gel or epoxy resin.
7. The display device according to any one of claims 1-7, wherein the material of the transparent substrate is polymethyl methacrylate or polycarbonate.
A backlight module, characterized in that it comprises a circuit board, a plurality of micro light emitting diodes arranged on the circuit board, covering the plurality of micro light emitting diodes and a protective glue layer of the circuit board, arranged on the The transparent substrate on the side of the protective glue layer facing away from the circuit board, and the diffuser plate disposed on the side of the transparent substrate facing away from the circuit board;

Wherein, the thickness of the transparent substrate satisfies the light mixing distance of the micro light emitting diode.