Microstructure composite diffusion plate with special shape and mini-led backlight module with microstructure composite diffusion plate with special shape

Abstract

The application discloses a special-shaped microstructure composite diffusion plate and a Mini-LED backlight module with the special-shaped microstructure composite diffusion plate. A valley pile type microstructure is arranged on the upper surface of the special-shaped microstructure composite diffusion plate, and a cylindrical microstructure is arranged on the lower surface of the special-shaped microstructure composite diffusion plate. The valley pile type microstructure has a square bottom surface and four curved edges. The valley pile type microstructure is used in combination with the cylindrical microstructure to increase the light uniformity of the special-shaped microstructure composite diffusion plate, and the special-shaped microstructure composite diffusion plate has better diffusion and light uniformity compared with a traditional diffusion plate, and has better two-dimensional light adjusting capacity.

Description

Technical Field

[0001] The present invention relates to the field of display technology, and in particular to a special-shaped microstructure composite diffuser plate and a Mini-LED backlight module having the special-shaped microstructure composite diffuser plate. Background Art

[0002] The concept of Mini-LED stems from the development of Micro-LED technology. While Micro-LED's advantages in the display field are clear, they remain some distance from market adoption due to the immaturity of key technologies such as mass transfer. While traditional LEDs typically measure in millimeters, Micro-LEDs typically measure in microns. It is generally considered that Mini-LED chips have a short-side dimension between 75 and 300μm. Due to its relatively low technical complexity and its benefits from liquid crystal display technology, Mini-LED technology has promising applications in LCD backlighting, becoming a major driving force behind Mini-LED development.

[0003] At present, direct backlight is the most commonly used backlight method for LCD displays. The direct backlight module can use ultra-fine local dimming technology to enhance the brightness and contrast of the display to obtain a better HDR effect. In order to ensure uniform light output, the direct backlight module mainly relies on the following three methods to convert the point light source into a uniform surface light source: 1. Use a sufficiently thick special-shaped microstructure composite diffuser plate; 2. Use a sufficiently large light mixing distance between the light source and the special-shaped microstructure composite diffuser plate; 3. Use enough Mini-LEDs (or the Mini-LED spacing is small enough). The increase in the thickness of the special-shaped microstructure composite diffuser plate and the poor light splitting effect of the existing special-shaped microstructure composite diffuser plate with a single pyramid structure have hindered the development of LCD displays towards ultra-thin displays. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to provide a special-shaped microstructure composite diffuser plate and a Mini-LED backlight module having a special-shaped microstructure composite diffuser plate, which has better diffusion and uniform light effect than traditional diffusers and better two-dimensional dimming capabilities.

[0005] To achieve the above-mentioned objectives, the present invention adopts the following technical solution: a special-shaped microstructure composite diffuser plate is assembled into a Mini-LED backlight module, the plate body of the special-shaped microstructure composite diffuser plate has an upper surface and a lower surface, a plurality of valley-type microstructures are arranged in an array on the upper surface of the special-shaped microstructure composite diffuser plate, and a plurality of cylindrical microstructures are arranged in an array on the lower surface of the special-shaped microstructure composite diffuser plate.

[0006] In a preferred embodiment, the valley-pile microstructure has a bottom surface having a vertex and four curved edges; the bottom surface side length of the valley-pile microstructure is d, the bottom side length of the cross-sectional profile of the valley-pile microstructure is √2d μm, the slope of the bottom end of the valley-pile microstructure is √3, the slope of the top end is √3 / 3, and the slope of the curve gradually decreases. The curve is described as follows: Where x represents the length of the bottom side of the cross-section of the valley-type microstructure, and y represents the height of the valley-type microstructure.

[0007] In a preferred embodiment, the bottom surface is a square bottom surface.

[0008] In a preferred embodiment, the side length of the square bottom surface of the valley-type microstructure is between 100 μm and 500 μm, and the height of the valley-type microstructure is between 81 μm and 408 μm.

[0009] In a preferred embodiment, the radius of the cylindrical microstructure is 5 μm to 100 μm, the chord height is 1 μm to 10 μm, and the radius of the cylindrical microstructure and the chord height of the cylindrical microstructure satisfy a relationship of 10:1.

[0010] In a preferred embodiment, the valley pile type microstructures are arranged in a rectangular array along the mutually perpendicular X-axis and Y-axis directions on the upper surface of the special-shaped microstructure composite diffuser plate; in the rectangular array, the multiple valley pile type microstructures include a first valley pile type microstructure, a second valley pile type microstructure, a third valley pile type microstructure, and a fourth valley pile type microstructure arranged at the four vertex positions on the upper surface of the special-shaped microstructure composite diffuser plate; the line segment formed by the first valley pile type microstructure and the second valley pile type microstructure as the two end points is parallel to the X-axis, the line segment formed by the first valley pile type microstructure and the fourth valley pile type microstructure as the two end points is parallel to the Y-axis, and the line segment formed by the first valley pile type microstructure and the third valley pile type microstructure as the two end points is the diagonal line of the special-shaped microstructure composite diffuser plate.

[0011] In a preferred embodiment, the cylindrical microstructures are arranged in sequence on the lower surface of the special-shaped microstructure composite diffuser plate, and the cylindrical microstructures are arranged in sequence according to the length of the radius, and the arrangement direction is parallel to the X-axis; the length of the cylindrical microstructure is equal to the length of the special-shaped microstructure composite diffuser plate in the direction of the Y-axis.

[0012] In a preferred embodiment, the material of the irregular microstructure composite diffuser plate includes at least one of the following: silicon dioxide SiO2, polycarbonate PC, polystyrene PS, polymethyl methacrylate PMMA, polypropylene PP, or a copolymer of any of the foregoing materials; the irregular microstructure composite diffuser plate contains a plurality of diffusion particles.

[0013] In a preferred embodiment, the material of the diffusion particles includes one of the following: silicon dioxide SiO2, titanium dioxide TiO2, polycarbonate PC, polystyrene PS, polymethyl methacrylate PMMA, polypropylene PP, or a copolymer of any of the foregoing materials; the particle diameter of the diffusion particles ranges from 0.5 μm to 10 μm, and the weight percentage concentration ranges from 1 to 100% wt.

[0014] The present invention also provides a Mini-LED backlight module with a special-shaped microstructure composite diffuser plate, comprising the above-mentioned special-shaped microstructure composite diffuser plate and a Mini-LED circuit substrate, wherein the Mini-LEDs are arranged in an array on the circuit substrate, and the spacing between adjacent Mini-LEDs in the X-axis direction and the Y-axis direction is 10 mm;

[0015] A reflector, the reflector being arranged on a surface of the Mini-LED circuit substrate;

[0016] The special-shaped microstructure composite diffuser plate has an OD distance of 5 mm between the bottom of the cylindrical microstructure and the top of the Mini-LED;

[0017] A color conversion film is located on the special-shaped microstructure composite diffuser. The color conversion film is an optical film containing quantum dot material or fluorescent material, which can convert part of the blue light energy into red and green light wavelengths, and finally emit white light;

[0018] A prismatic film is located on the color conversion film, and the prismatic film improves the brightness and viewing angle of the Mini-LED backlight module;

[0019] The composite optical film is located on the prism film, and the composite optical film improves the light output brightness and viewing angle range of the Mini-LED backlight module.

[0020] Compared with the existing technology, the present invention has the following advantages: 1. The valley-shaped microstructure on the upper surface of the special-shaped microstructure composite diffuser plate is different from the traditional single pyramid structure, which has a better light diffusion and uniformity effect. 2. The cylindrical microstructure on the lower surface of the special-shaped microstructure composite diffuser plate, combined with the valley-shaped microstructure on the upper surface, can further improve the light uniformity effect. 3. Compared with traditional diffusers, the special-shaped microstructure composite diffuser plate can achieve higher uniformity and better two-dimensional dimming effect when used in Mini-LED backlight modules. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 Schematic diagram of the structure of a Mini-LED backlight module with a special-shaped microstructure composite diffuser plate according to an embodiment of the present invention.

[0022] Figure 2It is a top view of the special-shaped microstructure composite diffuser plate of the present invention.

[0023] Figure 3 It is a three-dimensional enlarged schematic diagram of a pyramid microstructure set on a diffuser plate.

[0024] Figure 4 This is a schematic diagram of illumination simulation corresponding to the pyramid microstructure set on the diffuser plate.

[0025] Figure 5 It is a three-dimensional enlarged schematic diagram of multiple valley-type microstructures provided on the upper surface of the special-shaped microstructure composite diffuser plate of the present invention.

[0026] Figure 6 It is a cross-sectional profile diagram along the diagonal direction of multiple valley-type microstructures arranged on the upper surface of the special-shaped microstructure composite diffusion plate of the present invention.

[0027] Figure 7 It is a three-dimensional enlarged schematic diagram of multiple cylindrical microstructures provided on the lower surface of the special-shaped microstructure composite diffuser plate of the present invention.

[0028] Figure 8 This is a schematic diagram of illumination simulation of the Mini-LED backlight module with a special-shaped microstructure composite diffuser plate of the present invention.

[0029] Figure 9 This is a schematic diagram of the simulation of the two-dimensional dimming capability of the Mini-LED backlight module with a special-shaped microstructure composite diffuser plate of the present invention.

[0030] List of reference numerals: 10~special-shaped microstructure composite diffuser; 11~color conversion film; 12~second prism film; 13~first prism film; 14~composite optical film; 15~substrate; 16~reflector; 17~Mini-LED; 100~plate; 101~cylindrical microstructure; 102~valley pile type microstructure; 1021~first valley pile type microstructure; 1022~second valley pile type microstructure; 1023~third valley pile type microstructure; 1024~fourth valley pile type microstructure; 31~ Edge of pyramid microstructure; 32~base of pyramid microstructure; 33~base angle of pyramid microstructure; 1025~base of valley pile microstructure; 1026~curved edge of valley pile microstructure; 1027~diagonal line of base of valley pile microstructure; 1028~height of valley pile microstructure; 61~angle at the bottom of curved edge; 62~angle at the top of curved edge; 1011~radius of cylindrical microstructure; 1012~chord height of cylindrical microstructure; 1013~length of cylindrical microstructure. DETAILED DESCRIPTION

[0031] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0032] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which the present application belongs.

[0033] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application; as used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form, and it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or their combinations.

[0034] See also Figure 1-9 This embodiment provides a composite diffuser plate with a special-shaped microstructure for a Mini-LED backlight module, which includes: a composite optical film 14, a prism film (including a first prism film 13 and a second prism film 12), a color conversion film 11, a substrate 15, a Mini-LED 17, a reflective sheet 16, and a composite diffuser plate with a special-shaped microstructure 10. The composite diffuser plate with a special-shaped microstructure 10 includes: a plate body 100, a plurality of valley-shaped microstructures 102, and a plurality of cylindrical microstructures 101.

[0035] Specifically, the substrate 15 is provided with a circuit layout, and a plurality of Mini-LEDs 17 are arranged in an array on the substrate 15 and electrically coupled to the layout. In this embodiment, the Mini-LEDs 17 can be blue Mini-LEDs or white Mini-LEDs. The reflector 16 is provided on the substrate 15 and can be white or another color or surface with a good reflective effect. The reflector 16 is used to reflect the light emitted by the Mini-LEDs 17 upward toward the special-shaped microstructure composite diffuser plate 10. The material of the irregular microstructured composite diffuser plate 10 includes at least one of the following: silicon dioxide (SiO2), polycarbonate (PC), polystyrene (PS), polymethyl methacrylate (PMMA), polypropylene (PP), or a copolymer of any of the foregoing materials. The irregular microstructured composite diffuser plate contains a plurality of diffusion particles, each of which is made of one of the following: silicon dioxide (SiO2), titanium dioxide (TiO2), polycarbonate (PC), polystyrene (PS), polymethyl methacrylate (PMMA), polypropylene (PP), or a copolymer of any of the foregoing materials. The particle diameter of the diffusion particles ranges from 0.5μm to 10μm, and the weight percentage concentration ranges from 1% to 100% wt. The thickness of the irregular microstructured composite diffuser plate 10 is preferably between 0.2mm and 0.3mm. The distance (OD) between the irregular microstructured composite diffuser plate 10 and the top of the Mini-LED 17 is 5mm, and generally, no other components are located between the irregular microstructured composite diffuser plate 10 and the Mini-LED 17. In the present invention, the irregular microstructure composite diffuser plate 10 has a plate body 100, the plate body 100 has an upper surface and a lower surface, a plurality of the valley-shaped microstructures 102 are arranged in an array in the form of a rectangular arrangement on the upper surface of the plate body 100, and a plurality of the cylindrical microstructures 101 are arranged in an array form on the lower surface of the plate body 100.

[0036] Specifically, the color conversion film 11 is located on the special-shaped microstructure composite diffuser plate 10. In this embodiment, the color conversion film 11 includes an optical film of quantum dot material or fluorescent material, which can convert part of the blue light wavelength into red light wavelength or green light wavelength, and the final light output effect is the required white light.

[0037] Specifically, the first prism film 13 and the second prism film 12 are located above the color conversion film 11. The prism films 13, 12 can effectively improve the center viewing angle brightness of the backlight module by shrinking the angle of scattered light through the prism structure on the surface of the film. The prism films 13, 12 are based on polyethylene terephthalate (PET) as the substrate, and a prism structure is prepared on the upper surface of the substrate. The top angle of the prism structure ranges from 90° to 110°, and is generally 90°. The pitch of the prism is generally between 25 μm and 100 μm. In the present embodiment, the extension direction of the prisms of the first prism film 13 is orthogonal to the extension direction of the second prism film 14.

[0038] Specifically, the composite optical film 14 is located above the first prism film 13 and the second prism film 12. The composite optical film combines 2 to 3 optical films with different functions into the same film, and the currently widely used ones are POP (Prism On Prism), DOP (Diffuser On Prism), MOP (Micro Lens On Prism), COP (Core Layer On Prism), and COPP (Core Layer On POP). The composite optical film can further improve the light brightness and the viewing angle range. When light repeatedly acts in the structure in the film, most of the light that should be absorbed and lost is converted into available effective light.

[0039] Referring to Figure 2 , it is shown that Figure 2 is a top view of the composite diffusion plate with the special-shaped microstructure. The valley heap type microstructure is arranged in a rectangular array along the mutually perpendicular X-axis and Y-axis directions on the upper surface of the composite diffusion plate with the special-shaped microstructure. The rectangular array includes a first valley heap type microstructure 1021, a second valley heap type microstructure 1022, a third valley heap type microstructure 1023, and a fourth valley heap type microstructure 1024 arranged at the four vertex positions on the upper surface of the composite diffusion plate with the special-shaped microstructure. A line segment with the first valley heap type microstructure 1021 and the second valley heap type microstructure 1022 as two endpoints is parallel to the X-axis, and the distance between the first valley heap type microstructure 1021 and the second valley heap type microstructure 1022 is equal to the length of one side of the composite diffusion plate with the special-shaped microstructure 10. A line segment with the first valley heap type microstructure 1021 and the fourth valley heap type microstructure 1024 as two endpoints is parallel to the Y-axis, and the distance between the first valley heap type microstructure 1021 and the fourth valley heap type microstructure 1024 is equal to the length of the other side of the composite diffusion plate with the special-shaped microstructure 10. And a line segment with the first valley heap type microstructure 1021 and the third valley heap type microstructure 1023 as two endpoints is a diagonal line of the composite diffusion plate with the special-shaped microstructure.

[0040] See also Figure 3 shown. Figure 3 This is a magnified 3D illustration of a pyramid microstructure on a diffuser plate. Most existing diffuser plates currently available on the market feature a pyramid microstructure 30. The pyramid microstructure 30 has a square base 32 and four straight edges 31. The angles between the edges and the base are defined by the base angle 33, which is the slope of the straight edges. The four edges of the existing pyramid microstructure 30 refract or reflect light, resulting in a diffusion pattern corresponding to the Mini-LED light.

[0041] See also Figure 4 shown. Figure 4 This is a schematic diagram of the illumination simulation corresponding to the pyramid microstructure installed on the diffuser. Factors affecting the light diffusion include the base angle of the pyramid structure, the distance (OD) between the Mini-LED and the diffuser, the size and shape of the pyramid structure, and the refractive index of the material. Figure 4 The optical simulation results of 9 Mini-LEDs are as follows: the structure size is the same (the side length of the bottom square is 100μm), the OD is the same (such as 5mm), and the refractive index of the material is the same (such as 1.59). Figure 4 It can be seen intuitively from the figure that when the base angle 33 of the pyramid microstructure 30 is 30°, that is, when the slope of the pyramid microstructure 30 is small, the light of the Mini-LED 17 can be diffused. This is because when the large-angle light is refracted by the microstructure into small-angle light, the small-angle light will be reflected back into the optical cavity and reach the position of the reflector. When the base angle 33 of the pyramid microstructure 30 is 60°, that is, when the slope of the microstructure is large, the light angle is contracted in two directions, the angle of the outgoing light is small, and there is a certain diffusion effect on the light. The base angle 33 of the pyramid microstructure 30 has a certain diffusion effect on the light emitted by the Mini-LED 17 between 30° and 60°. However, since the base angle 33 is fixed, the diffusion effect on the light is limited.

[0042] See also Figure 5 As shown, Figure 5 It is a three-dimensional enlarged schematic diagram of multiple valley-type microstructures provided on the upper surface of the special-shaped microstructure composite diffuser plate of the present invention.

[0043] Specifically, the valley pile type microstructure 102 includes a square bottom surface 1025 and four curved edges 1026. The slope of the curved edges 1026 from the bottom to the top of the convex pyramid continuously decreases, gradually decreasing from 60° to 30°, which makes up for the shortcomings of the pyramid microstructure. The continuously changing slope can effectively diffuse the light at all angles emitted by the Mini-LED17.

[0044] Specifically, see Figure 6 As shown, Figure 6 This is a cross-sectional profile along the diagonal direction of multiple valley-shaped microstructures disposed on the upper surface of the irregularly shaped microstructured composite diffuser plate of the present invention. The cross-sectional profile includes: a valley-shaped microstructure bottom diagonal 1027, a valley-shaped microstructure height 1028, and a curved edge 1026. The direction of the convex pyramid bottom diagonal 1027 is defined as the X-axis, and the direction of the convex pyramid height 1028 is defined as the Y-axis. The intersection of the curved edge 1026 and the convex pyramid bottom diagonal 1027 is defined as the coordinate axis origin O. The angle 61 between the bottom end of the curved edge 1026 and the X-axis is 60°, and the angle 62 between the top end of the curved edge 1026 and the X-axis is 30°. The curved edge can be approximated as a parabola.

[0045] Specifically, the side length of the square bottom surface of the valley pile type microstructure 102 is d, the bottom diagonal line 1027 of the valley pile type microstructure is √2dμm, the slope of the bottom end of the valley pile type microstructure is √3, the slope of the top end is √3 / 3, and the slope of the curve gradually decreases. The curve can be described as: Where x represents the length of the bottom side of the cross-section of the valley-type microstructure, and y represents the height of the valley-type microstructure.

[0046] Specifically, the side length of the square bottom surface of the valley-type microstructure 102 is between 100 μm and 500 μm, and the height 1028 of the valley-type microstructure is between 81 μm and 408 μm.

[0047] See also Figure 7 , Figure 7 It is a three-dimensional enlarged schematic diagram of multiple cylindrical microstructures provided on the lower surface of the special-shaped microstructure composite diffuser plate of the present invention.

[0048] Specifically, the structural features of the cylindrical microstructure 101 include: a radius 1011 of the cylindrical microstructure, a chord height 1012 of the cylindrical microstructure, and a length 1013 of the cylindrical microstructure. The cross-section of the cylindrical microstructure 101 is a semi-cylindrical surface, but is not limited to a semicircle. The direction of the cylindrical microstructure radius 1011 is set as the X-axis, and the X-axis is parallel to one side of the shaped microstructure composite diffuser plate 10; the direction of the cylindrical microstructure length 1013 is set as the Y-axis, and the Y-axis is parallel to the other side of the shaped microstructure composite diffuser plate 10. The length 1013 of the cylindrical microstructure is equal to the length of the other side of the shaped microstructure composite diffuser plate 10.

[0049] Specifically, the radius 1011 of the cylindrical microstructure is 5 μm to 100 μm, the chord height 1012 of the cylindrical microstructure is 1 μm to 10 μm, and the radius 1011 of the cylindrical microstructure and the chord height 1013 of the cylindrical microstructure satisfy a relationship of 10:1.

[0050] See also Figure 8 , Figure 8 It is a schematic diagram of illumination simulation of the Mini-LED backlight module with a special-shaped microstructure composite diffuser plate of the present invention. Specifically, in this embodiment, the factors affecting the backlight module mainly include: the spacing between Mini-LEDs, the distance (OD) between the special-shaped microstructure composite diffuser plate and the Mini-LED, the special-shaped microstructure composite diffuser plate, etc. The Mini-LEDs 17 are arranged in an array on the circuit substrate, and the spacing between adjacent Mini-LEDs in the X-axis direction and the Y-axis direction is 10mm. The distance from the top of the Mini-LED to the bottom surface of the special-shaped microstructure composite diffuser plate is 5mm. From Figure 8 It can be seen that the Mini-LED backlight module using the special-shaped microstructure composite diffuser plate of the present invention achieves better uniformity. Compared with the Mini-LED backlight module using a traditional diffuser plate, the uniformity is improved from 81.3% to 93.07%. From the simulation results, it can be concluded that the application of the special-shaped microstructure composite diffuser plate of the present invention in the Mini-LED backlight module can further improve the uniformity.

[0051] In another embodiment, to achieve a more detailed and realistic display effect, LCD display technology requires a higher contrast ratio. The ambient contrast ratio of traditional LCD displays ranges from 1000:1 to 5000:1. Currently, direct-lit LCD modules use Mini-LEDs as the light source for the backlight module, combined with two-dimensional regional light control technology, to improve the ambient contrast ratio of LCD displays. In this embodiment, a Mini-LED lamp bead is used as a two-dimensional dimming zone. The size of each two-dimensional dimming zone is half the distance between the lamps, that is, the side length of the dimming zone in the X direction is 5mm, and the side length of the dimming zone in the Y direction is 5mm.

[0052] See also Figure 9 , Figure 9 The figure is a simulation diagram of the two-dimensional dimming capability of the Mini-LED backlight module with a special-shaped microstructure composite diffuser plate of the present invention. Specifically, in order to study the two-dimensional regional dimming capability of the microstructure optical film, the special-shaped microstructure composite diffuser plate of the present invention and the traditional diffuser plate are respectively applied to the Mini-LED backlight module, and only one Mini-LED chip in the center is lit to analyze the light pattern and uniformity within the dimming area. Figure 9The ray tracing results for illuminating the dimming unit in the center area when using the special-shaped microstructure composite diffuser plate of the present invention, as well as the illuminance curves in the horizontal and vertical directions at the center cross section, can be seen. It can be seen that within the specified dimming area, the illuminance varies slightly and has high uniformity. The illuminance decays rapidly after exceeding the dimming area. The entire light pattern is square, with 85% illuminance uniformity within the dimming area, and the light within the dimming area accounts for 31% of the total light. When using a traditional diffuser plate, the ray tracing results for illuminating the dimming unit in the center area, as well as the illuminance curves in the horizontal and vertical directions at the center cross section, show that within the specified dimming area, the illuminance varies significantly and has poor uniformity. The illuminance is highest at the center of the light source and decays rapidly toward the sides, resulting in a circular overall light pattern. The illuminance uniformity within the dimming area is 31%, and the light within the dimming area accounts for 37% of the total light. Simulation results show that the uniformity of the dimming area of ​​a Mini-LED backlight module using the special-shaped microstructure composite diffuser plate of the present invention is higher than that using a traditional diffuser plate architecture.

[0053] In another embodiment, the microstructure of the irregular microstructured composite diffuser plate can be processed using methods such as embossing, machining, hot embossing, micro-embossing, micro-injection molding, and LIGA (Lithographie, Galvanoformung, Abformung). LIGA processing is a hybrid technology combining photolithography, electroforming, and molding. During processing, a high-power synchrotron accelerator generates X-rays. The valley-shaped microstructure is fabricated on the upper surface of the irregular microstructured composite diffuser plate, and the cylindrical microstructure is fabricated on the lower surface. This is then electroformed to create a metal mold. After the mold is replicated, the desired irregular microstructured composite diffuser plate can be produced.

[0054] Matters not covered by the present invention are known technologies.

[0055] The above embodiments are intended only to illustrate the technical concepts and features of the present invention. Their purpose is to enable those skilled in the art to understand the contents of the present invention and implement them accordingly. They are not intended to limit the scope of protection of the present invention. Any equivalent changes or modifications made in accordance with the spirit of the present invention are intended to be covered by the scope of protection of the present invention.

Claims

1. A special-shaped microstructured composite diffuser plate, integrated into a Mini-LED backlight module, characterized by: The plate body of the special-shaped microstructure composite diffuser plate has an upper surface and a lower surface, a plurality of valley-shaped microstructures are arranged in an array on the upper surface of the special-shaped microstructure composite diffuser plate, and a plurality of cylindrical microstructures are arranged in an array on the lower surface of the special-shaped microstructure composite diffuser plate; The valley pile type microstructure has a bottom surface, the bottom surface has a vertex and four curved edges; the side length of the bottom surface of the valley pile type microstructure is d, and the side length of the bottom side of the cross-sectional profile of the valley pile type microstructure is dμm, the slope of the bottom of the valley-type microstructure is , the slope of the top is / 3, the slope of the curve gradually decreases, and the curve is described as: , where x represents the length of the bottom side of the cross-section of the valley-type microstructure, and y represents the height of the valley-type microstructure; The bottom surface is a square bottom surface; The side length of the square bottom surface of the valley-type microstructure is between 100 μm and 500 μm, and the height of the valley-type microstructure is between 81 μm and 408 μm; The radius of the cylindrical microstructure is 5 μm to 100 μm, and the chord height is 1 μm to 10 μm. The radius of the cylindrical microstructure and the chord height of the cylindrical microstructure satisfy a relationship of 10:

1.

2. The special-shaped microstructure composite diffuser plate according to claim 1, characterized in that: The valley pile type microstructure is arranged in a rectangular array along the mutually perpendicular X-axis and Y-axis directions on the upper surface of the special-shaped microstructure composite diffuser plate; the valley pile type microstructure includes a first valley pile type microstructure, a second valley pile type microstructure, a third valley pile type microstructure, and a fourth valley pile type microstructure arranged at the four vertex positions on the upper surface of the special-shaped microstructure composite diffuser plate; the line segment formed by the first valley pile type microstructure and the second valley pile type microstructure as the two end points is parallel to the X-axis, the line segment formed by the first valley pile type microstructure and the fourth valley pile type microstructure as the two end points is parallel to the Y-axis, and the line segment formed by the first valley pile type microstructure and the third valley pile type microstructure as the two end points is the diagonal line of the special-shaped microstructure composite diffuser plate.

3. The special-shaped microstructure composite diffuser plate according to claim 1, characterized in that: The cylindrical microstructures are arranged in sequence on the lower surface of the special-shaped microstructure composite diffuser plate. The cylindrical microstructures are arranged in sequence according to the length of the radius, and the arrangement direction is parallel to the X-axis; the length of the cylindrical microstructure is equal to the length of the special-shaped microstructure composite diffuser plate in the direction of the Y-axis.

4. The special-shaped microstructured composite diffuser plate according to claim 1, characterized in that: The material of the irregular microstructure composite diffuser plate includes at least one of the following: silicon dioxide SiO2, polycarbonate PC, polystyrene PS, polymethyl methacrylate PMMA, polypropylene PP, or a copolymer of any of the above materials; the irregular microstructure composite diffuser plate contains a plurality of diffusion particles.

5. The special-shaped microstructure composite diffuser plate according to claim 4, characterized in that: The material of the diffusion particles includes one of the following: silicon dioxide SiO2, titanium dioxide TiO2, polycarbonate PC, polystyrene PS, polymethyl methacrylate PMMA, polypropylene PP, or a copolymer of any of the above materials; the particle diameter of the diffusion particles ranges from 0.5μm to 10μm, and the weight percentage concentration ranges from 1~100%wt.

6. A Mini-LED backlight module with a special-shaped microstructure composite diffuser plate, characterized in that: A special-shaped microstructured composite diffuser plate comprising any one of claims 1 to 5, and comprising: Mini-LED circuit substrate, wherein the Mini-LEDs are arranged in an array on the circuit substrate, and the spacing between adjacent Mini-LEDs in the X-axis direction and the Y-axis direction is 10 mm; A reflector, which is arranged on the surface of the Mini-LED circuit substrate; The special-shaped microstructure composite diffuser plate has an OD distance of 5 mm between the bottom of the cylindrical microstructure and the top of the Mini-LED; A color conversion film is located on the special-shaped microstructure composite diffuser. The color conversion film is an optical film containing quantum dot material or fluorescent material, which can convert part of the blue light energy into red and green light wavelengths, and finally emit white light; A prismatic film is located on the color conversion film, and the prismatic film improves the brightness and viewing angle of the Mini-LED backlight module; The composite optical film is located on the prism film, and the composite optical film improves the light output brightness and viewing angle range of the Mini-LED backlight module.

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