Multi-layer packaging patterned scattering LED COB backlight source module and preparation method thereof

Abstract

The invention discloses a multi-layer packaging patterned scattering LED COB (Chip On Board) backlight source module and a preparation method thereof. A plurality of light-emitting unit bodies are distributed on the surface of a bottom layer substrate at intervals in an array mode; the scattering layer covers the light-emitting unit bodies and the unoccupied part of the bottom layer substrate; the transparent packaging layer covers the surface of the scattering layer; the low-transmittance layer covers the surface of the light-emitting unit body; one part of light emitted by the light-emitting unit bodies firstly passes through the scattering layer, then passes through the transparent packaging layer and finally passes through the low-transmittance layer to overflow, and the other part of light firstly passes through the scattering layer, then passes through the transparent packaging layer and finally returns to the scattering layer after being reflected by the low-transmittance layer; the particles in the scattering layer and / or the microstructure at the unoccupied part of the bottom surface of the bottom layer substrate are / is used for secondary scattering, and then the light overflows from the non-low-transmittance layer area so as to realize the homogenization of the light; the light perpendicular to the light-emitting surface of the LED chip is uniformly dispersed to other display areas by ingeniously utilizing colloid scattering or substrate scattering, so that the uniformity of the displayed light is greatly improved.

Description

Technical Field

[0001] The present invention relates to the technical field of LED display, and in particular to a multi-layer packaged patterned scattering LED COB backlight module and a preparation method thereof. Background Art

[0002] With the continuous progress of display technology, Mini-LED and Micro-LED technologies have gradually become emerging technologies in the display field due to their excellent performance such as high brightness, high contrast ratio, high color gamut and low power consumption.

[0003] These technologies are increasingly widely used in the fields of high-end TVs, laptops, monitors, etc.

[0004] Light emission uniformity is a key challenge in the development of Mini-LED and Micro-LED technologies, directly affecting the display effect and user experience. However, there are still many challenges in the practical applications of Mini-LED and Micro-LED display technologies.

[0005] First of all, the manufacturing process and equipment differences of LED chips will lead to brightness inconsistency problems;

[0006] Secondly, as a typical Lambertian light source, in the application of the display field, it is often difficult to achieve completely uniform brightness and chromaticity of the LED display.

[0007] This non-uniformity can be directly perceived by the human eye and manifested in regular or irregular forms such as dots, lines or planes, seriously affecting the overall consistency of the display effect.

[0008] Therefore, how to effectively solve the brightness uniformity problem of LED display has become the key to promoting the further development of this technology. Summary of the Invention

[0009] The purpose of the present invention is to overcome the above-mentioned shortcomings and deficiencies of the prior art, and provide a multi-layer packaged patterned scattering LED COB backlight module and a preparation method thereof. The present invention cleverly uses colloidal scattering or substrate bottom surface scattering to evenly disperse the light perpendicular to the light-emitting surface of the LED chip to other display areas, so that the display light emission uniformity is greatly improved.

[0010] The present invention is realized by the following technical solutions:

[0011] A multi-layer packaged patterned scattering LED COB backlight module, comprising a bottom substrate 11, a light-emitting unit body 21, a scattering layer 31, a transparent encapsulation layer 41 and a low-transmission layer 51;

[0012] There are multiple light-emitting unit bodies 21; the multiple light-emitting unit bodies 21 are arrayed and distributed on the surface of the bottom substrate 11 at intervals;

[0013] The scattering layer 31 covers the light-emitting unit body 21 and the vacant areas of the bottom substrate 11;

[0014] The transparent encapsulation layer 41 covers the surface of the scattering layer 31;

[0015] On the surface of the transparent encapsulation layer 41 corresponding to the position of each light-emitting unit body 21, a low-transmittance layer 51 is covered, and the low-transmittance layers 51 are spaced apart from each other; the area of each low-transmittance layer 51 is not less than the area of the light-emitting unit body 21 at its corresponding position;

[0016] The light emitted by the light-emitting unit body 21: a part first passes through the scattering layer 31, then through the transparent encapsulation layer 41, and finally overflows through the low-transmittance layer 51, while another part first passes through the scattering layer 31, then through the transparent encapsulation layer 41, and finally is reflected by the low-transmittance layer 51 and returns to the scattering layer 31 again; secondary scattering is carried out by using the particles in the scattering layer 31 and / or the microstructures 32 in the vacant areas on the bottom surface of the bottom substrate 11, and then overflows from the non-low-transmittance layer area, that is, the area of the transparent encapsulation layer 41 not covered by the low-transmittance layer 51, so as to realize the homogenization of light.

[0017] The vacant area refers to the surface of the bottom substrate 11 around the light-emitting unit body 21.

[0018] The microstructures 32 refer to concave and / or convex micro-particle array structures.

[0019] The scattering layer 31 is a silica gel layer doped with scattering particles TiO2.

[0020] The silica gel material used for the silica gel layer is silicon dioxide or titanium dioxide.

[0021] The low-transmittance layer 51 is an organosilicon layer or an epoxy resin layer doped with titanium nitride particles.

[0022] A preparation method of a multi-layer encapsulated patterned scattering LED COB backlight module includes the following steps:

[0023] S1, Fix the multiple light-emitting unit bodies 21 on the surface of the bottom substrate 11 in an orderly spaced manner by die bonding;

[0024] S2, Mold a scattering layer 31 above the light-emitting unit body 21, and the scattering layer 31 is completely adhered to the light-emitting unit body 21 and the bottom substrate 11;

[0025] S3, Mold a transparent encapsulation layer 41 above the scattering layer 31;

[0026] S4. Place a grid mold 61 above the transparent encapsulation layer 41. Each mesh hole position of the grid mold 61 corresponds to directly above the light-emitting unit body 21, and the mesh hole size is not less than the size of the light-emitting unit body 21. By means of printing, prepare a low-transparency layer 51 above the transparent encapsulation layer 41; then remove the grid to obtain a multi-layer encapsulated patterned-scattering LED COB backlight module.

[0027] In the above step S1, on the surface of the vacant area of the bottom substrate 11 around each light-emitting unit body 21, etch and manufacture microstructures 32.

[0028] In the above step S2, the scattering layer 31 is a silica gel layer containing scattering particles TiO2.

[0029] A method for uniformizing light scattering: The light emitted by the light-emitting unit body 21: a part of the light first passes through the scattering layer 31, then through the transparent encapsulation layer 41, and finally overflows through the low-transparency layer 51, while another part of the light first passes through the scattering layer 31 containing scattering particles, then through the transparent encapsulation layer 41, and finally after being reflected by the low-transparency layer 51, returns to the scattering layer 31 containing scattering particles again; utilize the scattering particles in the scattering layer 31 and / or the microstructures on the vacant area of the bottom surface of the bottom substrate 11 for secondary scattering, and then overflow from the non-low-transparency layer area, that is, the area where the transparent encapsulation layer 41 does not cover the low-transparency layer 51, thereby realizing the uniformization of light.

[0030] The present invention has the following advantages and effects compared with the prior art:

[0031] In the present invention, a micro-particle array protrusion structure 32 is arrayed and distributed on the surface of the vacant area of the bottom substrate 11 around the light-emitting unit body 21, greatly enhancing the light scattering ability of the substrate surface.

[0032] In the present invention, a transparent encapsulation layer is further molded above the scattering layer, and the transparent encapsulation layer is used to protect the scattering layer and at the same time play a role in laterally expanding the light.

[0033] In the present invention, a low-transparency layer is printed on the transparent encapsulation layer by using a grid mold, that is, the method of stencil printing. The low-transparency layer is distributed at the position directly above the light-emitting unit body 21 (LDE chip). The low-transparency layer has a blocking effect on the light emitted by the light-emitting unit body 21, and at the same time has strong light reflection on the inner surface. Cleverly utilize the characteristic of LED as a typical Lambert light source, with the strongest light emission in the vertical direction. In the vertical direction, a part of the light escapes through the low-transparency layer, and another part of the light is reflected into the scattering layer. After being scattered by the scattering particles in the scattering layer and the microstructured surface of the substrate, it escapes from the non-low-transparency layer area.

[0034] The technical means of the present invention are simple and easy to implement. By ingeniously utilizing the mechanism of colloidal scattering or substrate bottom surface structure scattering, the light perpendicular to the light-emitting surface of the LED chip is evenly dispersed to other display areas, greatly improving the light uniformity of the display. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 FIG. 1 is one of the schematic structural diagrams of the multi-layer packaged patterned scattering LED COB backlight module of the present invention.

[0036] Figure 2 FIG. Figure 1 FIG. 2 is a schematic diagram of the light-emitting principle of the multi-layer packaged patterned scattering LED COB backlight module.

[0037] Figure 3 FIG. 3 is another schematic structural diagram of the multi-layer packaged patterned scattering LED COB backlight module of the present invention.

[0038] Figure 4 FIG. Figure 3 FIG. 4 is a schematic diagram of the light-emitting principle of the multi-layer packaged patterned scattering LED COB backlight module.

[0039] Figure 5 FIG. Figure 1 FIG. 5 is a flow chart of the preparation method of the multi-layer packaged patterned scattering LED COB backlight module.

[0040] Figure 6 FIG. Figure 3 FIG. 6 is a flow chart of the preparation method of the multi-layer packaged patterned scattering LED COB backlight module.

[0041] In the figures: 100 represents the light transmission and light reflection area of the low-transparency layer; 200 represents the enlarged scattering area; 300 represents the colloidal scattering area; 400 represents the LED chip light-emitting area; 500 represents the scattering particle area; 600 represents the microstructure and its scattering area. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0042] The present invention will be further described in detail below with reference to specific embodiments.

[0043] As Figures 1-6 shown. The present invention discloses a multi-layer packaged patterned scattering LED COB backlight module, which includes a bottom substrate 11, a light-emitting unit body 21, a scattering layer 31, a transparent encapsulation layer 41, and a low-transparency layer 51;

[0044] There are multiple light-emitting unit bodies 21; the multiple light-emitting unit bodies 21 are arrayed on the surface of the bottom substrate 11 at intervals; the light-emitting unit body 21 is an LED chip, which can emit light of the same single color or different colors according to specific requirements.

[0045] The scattering layer 31 covers the light-emitting unit body 21 and the vacant areas of the bottom substrate 11; the material of the scattering layer 31 is generally silica gel, and the silica gel fills the height difference between the bottom substrate 11 and the light-emitting unit body 21, and finally forms a plane slightly higher than the light-emitting unit body 21.

[0046] The transparent encapsulation layer 41 covers the surface of the scattering layer 31; usually, the transparent encapsulation layer 11 is molded on the scattering layer 31, which can play a role in laterally expanding the light and can also protect the scattering layer 31.

[0047] On the surface of the transparent encapsulation layer 41 corresponding to each light-emitting unit body 21, a low-transparency layer 51 is covered, and the low-transparency layers 51 are spaced apart from each other; the area of each low-transparency layer 51 is not less than the area of the light-emitting unit body 21 at its corresponding position;

[0048] The light emitted by the light-emitting unit body 21: a part first passes through the scattering layer 31, then through the transparent encapsulation layer 41, and finally overflows through the low-transparency layer 51, while another part first passes through the scattering layer 31, then through the transparent encapsulation layer 41, and finally is reflected by the low-transparency layer 51 and then returns to the scattering layer 31 again; the particles in the scattering layer 31 and / or the microstructures 32 in the vacant areas on the bottom surface of the bottom substrate 11 are used for secondary scattering, and then overflow from the non-low-transparency layer area, that is, the area of the transparent encapsulation layer 41 that does not cover the low-transparency layer 51, thereby realizing the homogenization of light..

[0049] The vacant area refers to the surface of the bottom substrate 11 around the light-emitting unit body 21.

[0050] The microstructure 32 refers to a concave and / or convex microparticle array structure, which can be manufactured by etching and other methods.

[0051] The light-emitting unit body 21 refers to an LED.

[0052] The scattering layer 31 is a silica gel layer doped with scattering particles TiO2. The scattering layer can contain one or more scattering particles with different structural shapes or materials, which can disperse light, and the scattering layer 31, the light-emitting unit body 21 and the bottom substrate 11 are completely adhered.

[0053] The silica gel material used for the silica gel layer is silicon dioxide or titanium dioxide.

[0054] The low-transparency layer 51 is an organosilicon layer or an epoxy resin layer doped with titanium nitride particles.

[0055] A preparation method of a multi-layer encapsulated patterned scattering LED COB backlight module includes the following steps:

[0056] S1, fixing and distributing a plurality of light-emitting unit bodies 21 on the surface of the bottom substrate 11 in an orderly spaced manner;

[0057] S2. A scattering layer 31 is compression-molded above the light-emitting unit body 21, and the scattering layer 31 is completely attached to the light-emitting unit body 21 and the bottom substrate 11.

[0058] S3. A transparent encapsulation layer 41 is further compression-molded above the scattering layer 31.

[0059] S4. A grid mold 61 is placed above the transparent encapsulation layer 41. Each mesh position of the grid mold 61 corresponds to directly above the light-emitting unit body 21, and the mesh size is not less than the size of the light-emitting unit body 21. By printing, a low-transmittance layer 51 is prepared above the transparent encapsulation layer 41. Then the grid is removed to obtain a multi-layer encapsulated patterned-scattering LED COB backlight module.

[0060] In step S1, a micro-particle array protrusion structure 32 is etched and manufactured on the surface of the vacant part of the bottom substrate 11 around each light-emitting unit body 21.

[0061] In step S2, the scattering layer 31 is a silica gel layer containing scattering particles TiO2.

[0062] The LED COB backlight module of the present invention effectively expands the application field of LEDs. For the light emitted by the light-emitting unit body 21 of the present invention, a part of the light first passes through the scattering layer 31, then through the transparent encapsulation layer 41, and finally overflows through the low-transmittance layer 51, while another part of the light first passes through the scattering layer 31 containing scattering particles, then through the transparent encapsulation layer 41, and finally is reflected by the low-transmittance layer 51 and then returns to the scattering layer 31 containing scattering particles again. The scattering particles in the scattering layer 31 and / or the micro-structure at the vacant part of the bottom surface of the bottom substrate 11 are used for secondary scattering, and then overflow from the non-low-transmittance area, that is, the area of the transparent encapsulation layer 41 that does not cover the low-transmittance layer 51, so as to realize the uniformization of light.

[0063] As described above, the present invention can be preferably realized.

[0064] The implementation manners of the present invention are not limited by the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications made without departing from the spirit and principle of the present invention shall be equivalent replacement manners and are all included in the protection scope of the present invention.

Claims

1. A multi-layer encapsulated patterned scattering LED COB backlight module, characterized in that, It includes a bottom substrate (11), a light-emitting unit body (21), a scattering layer (31), a transparent encapsulation layer (41), and a low-transmittance layer (51); There are multiple light-emitting unit bodies (21); the multiple light-emitting unit bodies (21) are arrayed and distributed on the surface of the bottom substrate (11) at intervals; The scattering layer (31) covers the light-emitting unit bodies (21) and the vacant areas of the bottom substrate (11); The transparent encapsulation layer (41) covers the surface of the scattering layer (31); On the surface of the transparent encapsulation layer (41) corresponding to the position of each light-emitting unit body (21), a low-transmittance layer (51) is covered, and the low-transmittance layers (51) are spaced from each other; the area of each low-transmittance layer (51) is not less than the area of the light-emitting unit body (21) at its corresponding position; The light emitted by the light-emitting unit body (21): a part first passes through the scattering layer (31), then through the transparent encapsulation layer (41), and finally overflows through the low-transmittance layer (51), while another part first passes through the scattering layer (31), then through the transparent encapsulation layer (41), and finally is reflected by the low-transmittance layer (51) and returns to the scattering layer (31) again; The particles in the scattering layer (31) and / or the microstructures (32) in the vacant areas on the bottom surface of the bottom substrate (11) are used for secondary scattering, and then overflow from the non-low-transmittance layer area, that is, the area of the transparent encapsulation layer (41) not covered by the low-transmittance layer (51), thereby realizing the homogenization of light.

2. The multi-layer encapsulation patterned scattering LED COB backlight module according to claim 1, wherein The vacant area refers to the surface of the bottom substrate (11) around the light-emitting unit body (21).

3. The multi-layer encapsulation patterned scattering LED COB backlight module according to claim 2, wherein The microstructures (32) refer to concave and / or convex micro-particle array structures.

4. The multi-layer encapsulation patterned scattering LED COB backlight module according to claim 1, wherein The scattering layer (31) is a silica gel layer doped with scattering particles TiO2.

5. The multi-layer encapsulation patterned scattering LED COB backlight module according to claim 4, wherein The silica gel material used for the silica gel layer is silicon dioxide or titanium dioxide.

6. The multi-layer encapsulation patterned scattering LED COB backlight module according to claim 1, wherein The low-transmittance layer (51) is an organosilicon layer or an epoxy resin layer doped with titanium nitride particles.

7. A method for preparing the multi-layer encapsulated patterned scattering LED COB backlight module according to claims 1-6, characterized in that It includes the following steps: S1, Fix the multiple light-emitting unit bodies (21) on the surface of the bottom substrate (11) in an orderly and spaced manner; S2, Mold a scattering layer (31) above the light-emitting unit bodies (21), and the scattering layer (31) is completely adhered to the light-emitting unit bodies (21) and the bottom substrate (11); S3, Mold another transparent encapsulation layer (41) above the scattering layer (31); S4, Place a grid mold (61) above the transparent encapsulation layer (41), each mesh position of the grid mold (61) corresponds to directly above the light-emitting unit body (21), and the mesh size is not less than the size of the light-emitting unit body (21). By printing, a low-transmittance layer (51) is prepared above the transparent encapsulation layer (41); then the grid is removed to obtain a multi-layer encapsulated patterned scattering LED COB backlight module.

8. The preparation method of the multi-layer encapsulated patterned scattering LED COB backlight module according to claim 8, characterized in that: In step S1, on the surface of the vacant areas of the bottom substrate (11) around each light-emitting unit body (21), microstructures (32) are etched and manufactured.

9. The preparation method of the multi-layer encapsulated patterned scattering LED COB backlight module according to claim 8, characterized in that: In step S2, the scattering layer (31) is a silica gel layer containing scattering particles TiO2.

10. A method for homogenizing light scattering, characterized in that It is realized by using the multi-layer encapsulated patterned scattering LED COB backlight module described in any one of claims 1-7; The light emitted by the light-emitting unit (21): A part of the light first passes through the scattering layer (31), then through the transparent encapsulation layer (41), and finally through the low-transmittance layer (51) and overflows, while another part of the light first passes through the scattering layer (31) containing scattering particles, then through the transparent encapsulation layer (41), and finally after being reflected by the low-transmittance layer (51), it returns to the scattering layer (31) containing scattering particles again; Secondary scattering is carried out by using the scattering particles in the scattering layer (31) and / or the microstructures in the vacant area at the bottom surface of the bottom substrate (11), and then overflows from the non-low-transmittance layer region, that is, the region where the transparent encapsulation layer (41) does not cover the low-transmittance layer (51), thereby realizing the homogenization of light.

Images