WO2023216416A1

WO2023216416A1 - High light splitting ratio light guide plate, manufacturing method therefor, light source module and display assembly

Info

Publication number: WO2023216416A1
Application number: PCT/CN2022/106425
Authority: WO
Inventors: 方宗豹; 方慧; 张恒; 江山
Original assignee: 苏州维旺科技有限公司; 盐城维旺科技有限公司; 盐城维盛新材料有限公司; 苏州中为联创微纳制造创新中心有限公司
Priority date: 2022-05-12
Filing date: 2022-07-19
Publication date: 2023-11-16
Also published as: CN116736429A

Abstract

A high light splitting ratio light guide plate, a manufacturing method therefor, a light source module, and a display assembly. The high light splitting ratio light guide plate is applied to a light emitting side of a reflection-type liquid crystal display panel (7), and comprises: a light guide plate body (1), a plurality of first microstructures (2) being inwardly recessed in a reflection surface (13), each first microstructure (2) comprising an inclined surface (21), the inclined surface (21) facing a light incidence surface (11), and an included angle between the inclined surface (21) and the reflection surface (13) ranging from 27.5°-57.5°, so that the ratio of effective light emitting energy of a light emitting surface (12) to ineffective light emitting energy of the reflection surface (13) of the high light splitting ratio light guide plate is between 5:1 and 10:1, and the ratio of effective light emitting energy of the light emitting surface (12) to ineffective light emitting energy of the reflection surface (13) of the high light splitting ratio light guide plate in a front field of view being between 10:1 and 22:1. In each first microstructure (2), by arranging the inclined surface (21) facing the light incidence surface (11) at a reasonable angle, the propagation angle of light rays incident to the inclined surface (21) is adjusted, thus improving the proportion of effective light and ineffective light of the light guide plate, and simultaneously raising the picture contrast, especially the picture contrast of the front field of view.

Description

A high splitting ratio light guide plate and its preparation method, light source module, and display component

Technical field

The present invention relates to the technical field of reflective display devices, and in particular to a high splitting ratio light guide plate and a preparation method thereof, a light source module and a display assembly.

Background technique

Currently, liquid crystal displays (LCDs) can be divided into three types: transmissive LCDs, reflective LCDs, and transflective LCDs according to different lighting methods.

Among them, the reflective LCD mainly uses external ambient light as the light source. In order to realize that the reflective LCD can still display effectively when the ambient light is insufficient, the currently adopted technical solution is to set up a screen between the user and the reflective LCD. Light guide plate to use front light source for display when the environment is dark. Since the front light source (such as LED light source) has a certain divergence angle, the light emitted by the front light source will emit from both the upper and lower surfaces of the light guide plate after passing through the existing light guide plate, causing it to be incident on the reflective liquid crystal. The effective energy of the display is low, while the ineffective energy emitted directly from the light guide plate is high, which directly affects the contrast of the display.

Therefore, combined with the above existing technical problems, it is necessary to propose a new technical solution.

Contents of the invention

The present invention aims to solve one of the technical problems existing in the prior art, and proposes a high splitting ratio light guide plate and its preparation method, light source module and display assembly to improve the contrast of the light guide plate.

In order to achieve the purpose of the invention, in the first aspect, the invention provides a high splitting ratio light guide plate, including:

The light guide plate body includes a light incident surface, a light emergent surface and a reflective surface. The light incident surface and the light emergent surface are arranged oppositely, and the light incident surface is connected to the reflective surface and the light emergent surface respectively;

A plurality of first microstructures are recessed inwardly on the reflective surface. Each of the first microstructures includes an inclined surface, and the inclined surface faces the light incident surface. The inclined surface The angle between the reflective surface and the reflective surface ranges from 27.5° to 57.5°, so that the ratio of the effective light output energy of the light output surface of the high splitting ratio light guide plate to the ineffective light output energy of the reflective surface is between 5:1-10 : 1, and the ratio of the effective light-emitting energy of the light-emitting surface of the high-splitting-ratio light guide plate to the ineffective light-emitting energy of the reflective surface within the front field of view ranges from 10:1 to 22:1.

In a second aspect, the present invention provides a method for preparing a high splitting ratio light guide plate, including:

Provide a light guide plate body, the light guide plate body includes a light incident surface and a reflective surface;

Provide a light guide plate mold core;

The light guide plate mold core is used to form a plurality of first microstructures on the reflective surface of the light guide plate body through nanoimprinting, wherein the first microstructure includes an inclined surface, and the inclined surface faces the light incident surface, The angle range between the inclined surface and the reflective surface is 27.5°-57.5°.

In a third aspect, the present invention provides a light source module, including any one of the above-mentioned high splitting ratio light guide plates and a light source located on one side of the light incident surface of the high splitting ratio light guide plate.

In a fourth aspect, the present invention provides a display assembly, including any of the above light source modules and a reflective liquid crystal display panel, where the light source module is located on the light emitting side of the reflective liquid crystal display panel.

Compared with the existing technology, embodiments of the present application provide a high splitting ratio light guide plate, which is applied to the light exit side of a reflective liquid crystal display panel by setting the slope of the first microstructure facing the light incident surface at a reasonable angle. Within the range (27.5°-57.5°), the propagation angle of the light incident on the inclined surface can be adjusted to make the peak angle of the emergent light closer to the normal direction of the reflective surface, and the effective light exit angle of the light exit surface is controlled at -5°- 25° field of view, the ineffective light of the reflective surface is controlled to be greater than the 50° field of view, so that the ratio of the effective light energy of the light emitting surface of the high splitting ratio light guide plate to the ineffective light energy of the reflective surface is between 5:1- 10:1, and the ratio of the effective light output energy of the light output surface of the high split ratio light guide plate to the ineffective light output energy of the reflective surface within the front view field is between 10:1-22:1, which improves the contrast of the picture, especially in front view. Field picture contrast.

Description of the drawings

Figure 1 is a schematic cross-sectional structural diagram of a high splitting ratio light guide plate provided by an embodiment of the present application;

Figure 2 is a schematic diagram of the position of the first microstructure in the high splitting ratio light guide plate provided by the embodiment of the present application;

Figure 3 is a schematic diagram of the propagation of light in the high splitting ratio light guide plate provided by the embodiment of the present application;

Figure 4 is a schematic diagram of the relationship between the angle between the inclined surface of the first microstructure and the reflective surface and the light splitting ratio of the high splitting ratio light guide plate provided by the embodiment of the present application;

Figure 5 is a schematic diagram of the relationship between the effective light extraction and the ineffective light extraction and the field of view angle of the high splitting ratio light guide plate provided by the embodiment of the present application;

Figure 6 is a schematic distribution diagram of the first microstructure in the high splitting ratio light guide plate provided by the embodiment of the present application;

Figure 7 is a schematic distribution diagram of the second microstructure in the high splitting ratio light guide plate provided by the embodiment of the present application;

Figure 8 is a schematic diagram of the placement angle of a first microstructure in a high-resolution light guide plate provided by an embodiment of the present application;

Figure 9 is a schematic structural diagram of a high splitting ratio light guide plate provided by an embodiment of the present application;

Figure 10 is a schematic structural diagram of another high splitting ratio light guide plate provided by an embodiment of the present application;

Figure 11 is a schematic flow chart of a method for preparing a high splitting ratio light guide plate provided by an embodiment of the present application;

Figure 12 is a schematic diagram of a mold master preparation method provided by an embodiment of the present application;

Figure 13 is a schematic diagram of a method for forming microstructures by die impact according to an embodiment of the present application;

Figure 14 is a schematic structural diagram of a light source module provided by an embodiment of the present application;

Figure 15 is a schematic structural diagram of a display component provided by an embodiment of the present application;

Figure 16 is a schematic diagram of the relationship between the light energy emitted from the reflective surface and the light emitting surface of the high splitting ratio light guide plate and the viewing angle in Embodiment 1 of the present application;

Figure 17 is a schematic structural diagram of the first microstructure in Embodiment 2 of the present application;

Figure 18 is a schematic diagram of the relationship between the light energy emitted from the reflective surface and the light emitting surface of the high splitting ratio light guide plate and the viewing angle according to the second embodiment of the present application;

Figures 19A and 19B are two structural schematic diagrams of the first microstructure in Embodiment 3 of the present application;

Figure 20 is a schematic diagram of the relationship between the light energy emitted from the reflective surface and the light emitting surface of the high splitting ratio light guide plate and the viewing angle in three examples of embodiments of the present application;

Figure 21 is a schematic structural diagram of the first microstructure in Embodiment 4 of the present application;

Figure 22 is a schematic diagram of the relationship between the light energy emitted from the reflective surface and the light emitting surface of the high splitting ratio light guide plate and the viewing angle in four examples of the present application;

Figure 23 is a schematic structural diagram of the first microstructure in Embodiment 5 of the present application;

Figure 24 is a schematic diagram of the relationship between the light energy emitted from the reflective surface and the light emitting surface of the high splitting ratio light guide plate and the viewing angle in five examples of the present application;

Figure 25 is a schematic structural diagram of the first microstructure in Embodiment 6 of the present application;

Figure 26 is a schematic diagram of the relationship between the light energy emitted from the reflective surface and the light emitting surface of the high splitting ratio light guide plate and the viewing angle in six examples of the application;

27A to 27D are schematic diagrams showing the relationship between the effective light extraction and the ineffective light extraction and the viewing angle corresponding to the placement angles of the four first microstructures in the high-resolution light guide plate provided by the reference example of this application.

Detailed ways

In order to further elaborate on the technical means and effects adopted by the present invention to achieve the intended invention purpose, the specific implementation manner, structure, features and effects of the present invention are described in detail below in conjunction with the drawings and preferred embodiments.

Please refer to Figure 1. The high splitting ratio light guide plate according to the embodiment of the present application is applied to the light exit side of the reflective liquid crystal display panel. The high splitting ratio light guide plate includes:

The light guide plate body 1 includes a light incident surface 11, a light emergent surface 12 and a reflective surface 13. The light incident surface 11 and the light emergent surface 12 are arranged oppositely. The light incident surface 11 is respectively connected with the reflective surface 13 and the reflective surface 13. The light-emitting surfaces 12 are connected;

A plurality of first microstructures 2 are recessed inwardly on the reflective surface 13 . Each first microstructure 2 includes an inclined surface 21 , the inclined surface 21 faces the light incident surface 11 , and the inclined surface 21 and the reflective surface 13 The angle range of the included angle is 27.5°-57.5°, so that the ratio of the effective light-emitting energy of the light-emitting surface of the high splitting ratio light guide plate to the ineffective light-emitting energy of the reflective surface is between 5:1-10:1, and the The ratio of the effective light-emitting energy of the light-emitting surface of the high-split-ratio light guide plate to the ineffective light-emitting energy of the reflective surface within the front field of view ranges from 10:1 to 22:1.

Here, the reflective surface 13 and the light-emitting surface 12 are respectively at an angle with the light-incident surface 11. The reflective surface 13 and the light-emitting surface 12 may be at an angle or parallel. Preferably, the reflective surface 13 and the light-emitting surface 12 are parallel and perpendicular to the light-incident surface 11 .

In this embodiment, the ratio of the effective light output energy of the light output surface 12 of the high splitting ratio light guide plate to the ineffective light output energy of the reflective surface 13 is the splitting ratio of the high splitting ratio light guide plate, hereinafter referred to as the splitting ratio. Generally, the light guide plate used in reflective LCD panels requires that its light splitting ratio is not less than 5:1, and the optimal angle incident on the reflective LCD panel is between 0 and 20°, that is, it is used in reflective LCD panels. The peak effective light emission angle of the light guide plate of the liquid crystal display panel is between 0 and 20°.

Here, the front field of view range of the high splitting ratio light guide plate specifically refers to the field of view range of -5°-25°.

The high splitting ratio light guide plate of this embodiment can be used in a reflective liquid crystal display. The high splitting ratio light guide plate of the reflective liquid crystal display is located on the light exit side of the reflective liquid crystal display panel. After the light is emitted from the light exit surface 12 of the high splitting ratio light guide plate, The light is incident on the reflective liquid crystal display panel and reflected by the reflective liquid crystal display panel to the light receiving device of the reflective liquid crystal display or a human observer.

Please continue to refer to FIG. 1 . A plurality of first microstructures 2 are formed inwardly on the reflective surface 13 . Each first microstructure 2 includes an inclined surface 21 and another inclined surface 22 . The inclined surface 21 faces the light incident surface 11 , and the inclined surface 21 The included angle with the reflective surface 13 ranges from 27.5° to 57.5°. That is, the inclined surface 21 faces the light incident surface 11 , and the first side of the inclined surface 21 starts from the reflective surface 13 in the light guide plate body 1 and tilts away from the light incident surface 11 , so that the inclined surface 21 and the reflective surface 13 The angle range of . That is, the first microstructure 2 reflects most of the light incident or reflected to the first microstructure 2 through the slope 21 .

It is understandable that the other inclined surface 22 of the first microstructure 2 can also be in other shapes, such as a curved surface or other irregular shapes, and the embodiment of the present application does not limit this.

In some embodiments, the first side of the slope 21 may not start from the reflective surface 13 in the light guide plate body 1 , but may start from any position in the light guide plate body 1 . At the same time, in order to tilt the inclined surface 21 away from the light incident surface 11 , the distance from the second side of the inclined surface 21 to the light incident surface 11 is greater than the distance from the first side of the inclined surface 21 to the light incident surface 11 , where the first side The second side is the two sides opposite to the inclined plane 21. The distance from the first side or the second side to the light incident surface 11 is the midpoint of the first side or the midpoint of the second side to the light incident surface. 11 distance.

In some embodiments, one side of the inclined surface 21 starts from the reflective surface 13 in the light guide plate body 1 .

Furthermore, the angle between the inclined surface 21 and the reflective surface 13 refers to the angle between the inclined surface 21 and the plane where the reflective surface 13 is located. Specifically, please refer to FIG. 2 . Line segment AB is a line segment cut on the inclined plane 21 by a reference plane, where the reference plane is a plane perpendicular to the reflective surface 13 . Since the inclined surface 21 is inclined away from the light incident surface 11 from the reflective surface 13 , the distance from the end point B of the line segment AB to the light incident surface 11 is greater than the distance from the end point A to the light incident surface 11 .

At the same time, the angle between the inclined surface 21 and the reflective surface 13 is also the angle CAB, that is, α. Here, the angle range of α is 27.5°-57.5°. Preferably, the angle range of α is 32.5°-45°; more preferably, the angle range of α is 35°-43°.

It can be understood that in a preferred case, the first microstructure 2 can reflect more than 80% of the light incident or reflected to the first microstructure 2 through the slope 21 .

In this embodiment, the distribution rule of the first microstructures 2 on the reflective surface 13 can be random distribution or distribution according to a preset distribution rule, such as array distribution, distribution according to a distribution density trend, etc.

Here, there is a spacing between the first microstructures 2 .

In the embodiment of the present application, a plurality of first microstructures 2 are arranged on the reflective surface 13 of a high splitting ratio light guide plate. After the light emitted by the LED is coupled into the high splitting ratio light guide plate, it is refracted and/or reflected by the first microstructures 2 , its propagation direction will change.

Please refer to FIG. 3 , which is a schematic diagram of light propagation simulation of a high splitting ratio light guide plate based on an embodiment of the present application, in which the angle between the inclined surface 21 and the reflective surface 13 is α.

Specifically, part of the light is finally emitted from the light exit surface 12 after being reflected or refracted and reflected by at least one first microstructure 2 . For example, in Figure 3, the exit angles are rays corresponding to θ1, θ2, and θ3.

Here, the light L1 with the exit angle θ1 is taken as an example for explanation: the light L1 is coupled from the light incident surface 11 of the high splitting ratio light guide plate at the incident angle γ, propagates forward at the angle δ in the high splitting ratio light guide plate, and The light is incident on the inclined surface 21 of the first microstructure 2 at an angle η, is reflected by the inclined surface 21, and is emitted from the light exit surface 12 of the high splitting ratio light guide plate at an angle θ1.

During the propagation process of the above light L1, it satisfies:

sin(γ)＝n*sin(δ) (1)

Among them: n is the refractive index of the high splitting ratio light guide plate base material.

η＝90°–α–δ (2)

ε＝2*η+δ–90° (3)

From the above formulas (2) and (3), we get:

ε＝90°–2*α–δ (4)

Let the emission angle from the light emission surface of the high splitting ratio light guide plate be θ1～0°, then ε=0°;

Then formula (4) is simplified to:

α＝45°–δ/2 (5)

From formulas (1) and (5), we get:

α＝45°–arcsin(sin(γ)/n)/2 (6)

Obviously, for the light guide plate base material with a specific refractive index, in order to make the light emit from the light exit surface 12 of the high splitting ratio light guide plate at a vertical angle or a smaller angle, the slope 21 and the reflective surface of the first microstructure 2 can be reasonably set. The angle α of 13.

Here, preferably, the angle α between the inclined surface 21 of the first microstructure 2 and the reflective surface 13 ranges from 27.5° to 57.5°.

At the same time, part of the light will also emit from the reflective surface 13 of the high splitting ratio light guide plate at a larger exit angle, and this part of the light will be invalid light. For example, ray L2 in Figure 3.

In addition, some of the light will always propagate in the high splitting ratio light guide plate due to total reflection before it is incident on the first microstructure 2 . For example, ray L3 in Figure 3.

Further, please continue to refer to Figure 3. Based on the high splitting ratio light guide plate of the embodiment of the present application, the density of effective light is greater than the density of ineffective light, where the density of effective light is the number of effective light emitted from the unit light exit surface 12, and the ineffective light The density of light is the number of ineffective light rays emitted from the unit reflection surface 13 .

Further, the angle between the inclined surface 21 of the first microstructure on the high-fraction light guide plate and the reflective surface 13 and the splitting ratio of the high-dimension ratio light guide plate satisfy the following relationship:

y＝0.1159x ² +1.7062x+2.9168 (7)

In the above formula (7), y is the splitting ratio, and x is the angle between the inclined surface 21 and the reflective surface 13, in degrees.

Based on the high splitting ratio light guide plate provided in the embodiment of the present application, please refer to Figure 4. When the angle between the inclined surface 21 and the reflective surface 13 is set at 27.5°-57.5°, the splitting ratio of the high splitting ratio light guide plate can be between 5: 1-10:1.

Specifically, please continue to refer to Figure 4. When the angle between the bevel 21 and the reflective surface 13 is set at 27.5°, the light splitting ratio of the high splitting ratio light guide plate is 5:1; when the angle between the bevel 21 and the reflective surface 13 is set at At 42.5°, the light splitting ratio of the high splitting ratio light guide plate is 9.6:1.

Further, when the angle between the inclined surface 21 of the high splitting ratio light guide plate and the reflective surface 13 is set at 42.5°, Figure 5 is a schematic diagram of the relationship between the effective light output energy and the ineffective light output energy of the high splitting ratio light guide plate and the field of view angle respectively. Please refer to Figure 5. The peak value of the effective light emission angle of the high splitting ratio light guide plate is around 0°, and 75% of the effective light emission energy is concentrated in the front field of view (-5°-25°). The peak value of the ineffective light emission angle is around 73°. Only 25% of the ineffective light energy is concentrated in the front view field (-5°-25°); the split ratio is 9.6:1, and the split ratio in the front view field is 22:1, which greatly improves the performance of the high splitting ratio light guide plate of the present application in front view The splitting ratio of the field.

In summary, based on the high splitting ratio light guide plate provided in the embodiment of the present application, by setting the slope of the first microstructure facing the light incident surface within a reasonable angle range (27.5°-57.5°), the incident light can be adjusted to the The light propagation angle of the inclined surface makes the peak angle of the emergent light closer to the normal direction of the reflective surface. The effective light exit angle of the light exit surface is controlled within the field of view of -5°-25°, and the ineffective light of the reflective surface is controlled to be greater than 50°. The field of view is such that the ratio of the effective light output energy of the light output surface of the high splitting ratio light guide plate to the ineffective light output energy of the reflective surface is between 5:1-10:1, and the high splitting ratio light guide plate is viewed from the front The ratio of the effective light-emitting energy of the light-emitting surface within the field range to the ineffective light-emitting energy of the reflective surface is between 10:1-22:1, which improves the picture contrast, especially the picture contrast in the front view field.

In some embodiments, please continue to refer to Figure 1. The high splitting ratio light guide plate also includes:

A plurality of second microstructures 3 are recessed inwardly on the reflective surface 13 . Each second microstructure 3 includes an arcuate surface 31 , and the arcuate surface 31 faces the light incident surface 11 .

Specifically, a plurality of second microstructures 3 are formed inwardly on the reflective surface 13 , and each second microstructure 3 includes an arc surface 31 , and the arc surface 31 faces the light incident surface 11 . That is, the arc surface 31 faces the light incident surface 11, and the third side of the arc surface 31 starts from the reflective surface 13 in the light guide plate body 1 and tilts away from the light incident surface 11, so that the light passes from the incident surface 11 to the light incident surface 11. After the light surface 11 is incident, most of the light incident or reflected to the second microstructure 3 will be reflected through the arc surface 31 of the second microstructure 3 . That is, the second microstructure 3 reflects most of the light incident or reflected to the second microstructure 3 through the arc surface 31 .

In some embodiments, the third side of the arcuate surface 31 may not start from the reflective surface 13 in the light guide plate body 1 , but may start from any position in the light guide plate body 1 . At the same time, in order to tilt the arc surface 31 away from the light incident surface 11 , the distance from the fourth side of the arc surface 31 to the light incident surface 11 is greater than the distance from the third side of the arc surface 31 to the light incident surface 11 , where the fourth side The side and the third side are two opposite sides of the arc surface 31. The distance from the third side or the fourth side to the light incident surface 11 is from the midpoint of the third side or the midpoint of the fourth side to The distance from the light incident surface 11.

In some embodiments, the arc surface 31 is a smooth regular arc surface.

It can be understood that, in a preferred situation, the second microstructure 3 reflects more than 80% of the light incident or reflected to the second microstructure 3 through the arcuate surface 31 .

In this embodiment, the arc surface 31 is convex toward the light incident surface 11 , or the arc surface 31 is concave toward the light incident surface 11 . Preferably, the arc surface 31 is convex toward the light incident surface 11 .

In this embodiment, the distribution rule of the second microstructure 3 on the reflective surface 13 can be random distribution or distribution according to a preset distribution rule, such as array distribution, distribution according to a distribution density trend, etc.

Further, there is a gap between the second microstructures 3 and between the first microstructures 2 and the second microstructures 3 .

The embodiment of the present application introduces a plurality of second microstructures 3 on the light entrance side to disperse the light on the light entrance side, destroy the directional propagation law of light, and eliminate the Hotspot phenomenon on the light entrance side of the light guide plate (i.e., the light guide plate When using LED as the light source, due to the limited divergence angle of the LED light source, the light beam appears bright in the area of the light guide plate close to the LED light source, resulting in uneven light and dark. This phenomenon reduces the uniformity of the light output from the light guide plate, and at the same time It also affects the subjective effect of the backlight) and adjusts the uniformity of light output from the entire light guide plate.

In some embodiments, the angle between the inclined surface 21 of the first microstructure 2 and the reflective surface 13 is 32.5°-45°.

In this embodiment, when the angle between the inclined surface 21 of the first microstructure 2 and the reflective surface 13 is 32.5°-52.5°, the ratio of the effective light output energy of the light output surface of the high splitting ratio light guide plate to the ineffective light output energy of the reflective surface It can range from 7:1 to 10:1.

In some embodiments, the first microstructure 2 is one or more of a pyramid, a prism, a partial sphere and a partial cylinder.

Specifically, in one embodiment, the first microstructure 3 is a pyramid, and the bottom surface of the pyramid is on the same plane as the reflective surface 13 . Then the inclined surface 21 of the first microstructure 2 is a side surface of the pyramid, and the side surface faces Light incident surface 11.

It can be understood that the first microstructure 3 can also be a prism.

In another embodiment, the first microstructure 3 is a prism, the bottom surface of the prism is on the same plane as the reflective surface 13 , and the edges of the prism are inclined away from the light incident surface 11 from the reflective surface in the light guide plate body 1 , then the inclined surface 21 of the first microstructure 2 is a side surface of the prism, and the side surface faces the light incident surface 11 .

In another embodiment, the first microstructure 3 is a partial sphere, and the partial sphere can be a part of a sphere intercepted based on an inclined plane. The partial sphere includes the inclined plane and a part of the sphere, and the inclined plane faces the light incident surface 11 , and the included angle with the reflective surface 13 ranges from 27.5° to 57.5°, and this inclined surface is the inclined surface 21 of the first microstructure 2 .

It can be understood that the partial sphere can be a hemisphere, a 1/4 sphere, a 1/8 sphere, etc.

In another embodiment, the first microstructure 3 is a partial cylinder, and the partial cylinder may be a part of a cylinder cut based on an inclined plane. The partial cylinder includes an inclined plane and a partial cylinder, and the inclined plane faces The angle between the light incident surface 11 and the reflective surface 13 ranges from 27.5° to 57.5°. This inclined surface is the inclined surface 21 of the first microstructure 2 .

It can be understood that the partial cylinder can be 1/2 cylinder, 1/4 cylinder, 1/8 cylinder, etc.

Obviously, the above are only examples of some specific structures of the first microstructure 2. The specific structure of the first microstructure 2 in the embodiment of the present invention is not limited to this. It can also be other regular or irregular structures. It only needs to be ensured that it has an inclined surface, which faces the light incident surface 11 , and the angle range between the inclined surface and the reflective surface 13 is 27.5°-57.5°.

In some embodiments, the bevel 21 of the first microstructure 2 is an optically smooth surface, and the roughness Ra of the bevel 21 is 30 nm-150 nm. For example, the surface roughness of the inclined surface 21 is 100 nm, etc., so that the light incident or reflected thereon can be specularly reflected.

In some embodiments, the second microstructure 3 is one or more of a hemispherical shape, a cylindrical shape, a water drop shape, and a horseshoe shape.

Specifically, in one embodiment, the second microstructure 3 is hemispherical, and the bottom surface of the hemisphere is on the same plane as the reflective surface 13 , so the arc surface 31 of the second microstructure 3 is a partial spherical surface of the hemisphere. The spherical surface faces the light incident surface 11. Here, it can be understood that the second microstructure 3 can also be partially spherical, that is, a part of the sphere, such as 1/2 sphere, 1/4 sphere, 1/8 sphere, etc. The arc surface 31 of the second microstructure 3 is The partial spherical surface is all or part of the spherical surface, and the whole or part of the spherical surface faces the light incident surface 11 .

In another embodiment, the second microstructure 3 is cylindrical, the bottom surface of the cylindrical shape is on the same plane as the reflective surface 13 , and the axis of the cylinder is inclined away from the reflective surface 13 in the direction away from the light incident surface 11 in the light guide plate body 1 , then the arc surface 31 of the second microstructure 3 is a partial side surface of the cylinder, and this partial side surface faces the light incident surface 11 .

In another embodiment, the second microstructure 3 is in the shape of a water drop. The axis of the water drop shape is inclined away from the light incident surface 11 from the reflective surface in the light guide plate body 1 . The arc surface 31 of the second micro structure 3 is in the shape of a water drop. Part of the outer surface of the structure, this part of the outer surface faces the light incident surface 11.

In another embodiment, the axis of the second microstructure 3 is a horseshoe shape and the self-reflective surface in the light guide plate body 1 is inclined away from the light incident surface 11 . The arc surface 31 of the second microstructure 3 is part of the outer surface of the horseshoe-shaped structure. , the outer surface of this part faces the light incident surface 11.

It can be understood that the above are only examples of some specific structures of the second microstructure 3. The specific structure of the second microstructure 3 in the embodiment of the present invention is not limited to this. It can also be other regular or irregular structures. It only needs to be ensured that it has an arc surface facing the light incident surface 11, and preferably, the arc surface is a regular curved surface.

In some embodiments, the arc surface 31 of the second microstructure 3 is an optically smooth surface, and the roughness of the arc surface 31 is 30 nm-150 nm. For example, the surface roughness of the curved surface 31 is 100 nm, so that the light incident or reflected thereon can be specularly reflected.

In some embodiments, please refer to FIG. 6 , the first spacing between any two adjacent first microstructures 2 varies from the two adjacent first microstructures 2 to the incident light. The first average distance of the surface 11 decreases as the first distance increases, and the first distance and the first average distance satisfy an index with the first average distance as the independent variable and the first distance as the dependent variable. Functional relationship.

Here, please refer to Figure 6. Taking two adjacent first microstructures M and N as an example, the first average distance refers to the distance d1 from the first microstructure M to the light incident surface 11 and the distance d1 from the first microstructure N to the light incident surface 11. The average value of the distance d2 of the light surface 11, that is, the first average distance d3 is (d1+d2)/2. Among them, when determining the distance d1 from the first microstructure M to the light incident surface 11 and the distance d2 from the first microstructure N to the light incident surface 11, they are based on the same structures of the first microstructure M and the first microstructure N respectively. The position is determined, for example, d1 and d2 are determined based on the point on the first microstructure M that is closest to the light incident surface and the point on the first microstructure N that is closest to the light incident surface. It is understandable that when d1 and d2 are determined, the determination can also be based on the point on the first microstructure M and the first microstructure N that is farthest from the light incident surface, the geometric center, the center of gravity, etc.

In this embodiment, the exponential function relationship between the first average distance d3 and the first distance D1 can be expressed as follows:

D1＝a*(d3) ^b +D0 (8)

In the above formula (8), a and b are constants, and 0<a<1, 1<b<5, D0 is the preset distance from a first microstructure 2 to the light incident surface 11, such as: D0 is The distance from the first microstructure 2 to the light incident surface 11 which is the smallest distance from the light incident surface 11 .

In some embodiments, the distribution density of the first microstructures 2 on the reflective surface 13 tends to increase from the light incident surface 11 to the direction away from the light incident surface 11 . The direction from the light incident surface 11 to the direction away from the light incident surface 11 refers to the direction from the light incident surface 11 to its opposite surface on the reflective surface 13 of the light guide plate body 1 . For example, the direction from the light incident surface 11 to the direction away from the light incident surface 11 is the direction S shown in FIG. 5 . Along the direction S, the distribution density of the first microstructures 2 on the reflective surface 13 gradually increases.

Furthermore, the reflective surface 13 can be divided into multiple regions in sequence starting from the light incident surface 11 . Among the multiple regions starting from the light incident surface 11 , the first microstructure 2 in the region that is farther away from the light incident surface 11 is smaller. The greater the density. Here, the multiple areas can be areas of the same size on the reflective surface 8 or areas of different sizes, and the areas of the multiple areas can be set to a smaller area unit according to actual application needs, such as square millimeters, square micrometers, etc., to more accurately control the distribution of the first microstructure 2 on the light guide plate body 1.

Specifically, please continue to refer to Figure 6. The reflective surface 13 is divided into areas A, area B, area C and area D in order from the light incident surface 11. The first microstructure 2 is in area A, area B, area C and area D. The density increases successively.

Further, in some embodiments, please refer to FIG. 7 , the second spacing between any two adjacent second microstructures 3 varies from the two second microstructures 3 to the incident light. The second average distance of the surface 11 increases with the increase, and the second distance and the average distance satisfy the exponential function relationship with the second average distance as the independent variable and the second distance as the dependent variable. .

Here, please refer to Figure 7. Taking two adjacent second microstructures P and Q as an example, the second average distance refers to the distance d4 from the second microstructure P to the light incident surface 11 and the distance d4 from the second microstructure Q to the light incident surface. The average value of the distance d5 of the smooth surface 11, that is, the second average distance d6 is (d4+d5)/2. Among them, when determining the distance d4 from the second microstructure P to the light incident surface 11 and the distance d5 from the second microstructure Q to the light incident surface 11, they are based on the same structures of the second microstructure P and the second microstructure Q respectively. The position is determined, for example, d4 and d5 are determined based on the point on the second microstructure P that is closest to the light incident surface and the point on the second microstructure Q that is closest to the light incident surface. It is understandable that when d4 and d5 are determined, they can also be determined based on the point on the second microstructure P and the second microstructure Q that is farthest from the light incident surface, the geometric center, the center of gravity, etc.

In this embodiment, the exponential function relationship between the second average distance d6 and the second distance D2 can be expressed as follows:

D2＝e*(1/d6) ^f +D` (9)

In the above formula (9), e and f are constants, and 0<e<1, 1<f<10, D` is the preset distance from a second microstructure 3 to the light incident surface 11, such as: D ` is the distance from the second microstructure 3 with the smallest distance to the light incident surface 11 to the light incident surface 11 .

In some embodiments, the distribution density of the second microstructure 3 on the reflective surface 13 tends to decrease from the light incident surface 11 to the direction away from the light incident surface 11 .

Here, along the direction S, the distribution density of the second microstructure 3 on the reflective surface 13 gradually decreases.

In this embodiment, the second microstructure 3 is only provided in a predetermined area, and the preset area may be part or all of the reflective surface 11 .

For example, the preset area may be a 1/3-1/2 area on the reflective surface 11 from the light incident surface 11 to a distance away from the light incident surface 11 . That is, the preset area occupies 1/3-1/2 of the entire reflective surface, starting from the junction between the light incident surface 11 and the reflective surface 13 .

Furthermore, the preset area can be divided into multiple areas in sequence starting from the light incident surface 11 . Among the multiple areas starting from the light incident surface 11 , the second microstructure 3 in the area that is farther away from the light incident surface 11 is smaller. The density is smaller. Here, the multiple areas can be areas of the same size within the preset area, or areas of different sizes, and the areas of the multiple areas can be set to a smaller area unit according to actual application needs, such as square millimeters, square micrometers, etc., to more accurately control the distribution of the preset area on the light guide plate body 1.

Specifically, please continue to refer to Figure 7. The preset area is divided into area E, area F, area G and area H in order from the light incident surface 11. The density of the preset area in area E, area F, area G and area H is Decrease in turn.

Since the first microstructures 2 with bevel design have high light-guiding efficiency, a small number of them are provided near the light-incident surface 11. At the same time, the second microstructures 3 with low light-guiding efficiency are added. The combination of the two can effectively reduce the number of front-end microstructures. The hot spot or light spot phenomenon of the light module near the LED light bar improves the quality of the screen display.

In some embodiments, the length and width of the first microstructure 2 range from 10um to 40um.

In some embodiments, the depth of the first microstructure 2 ranges from 3um to 20um.

In some embodiments, the length and width of the second microstructure 3 are both in the range of 5um-20um.

In some embodiments, the depth of the second microstructure 3 ranges from 3um to 15um.

Here, a spatial coordinate system is established to better describe the dimensions of the first microstructure 2 and the second microstructure 3 . Specifically, please refer to FIG. 8 , taking the size of the first microstructure 2 in the spatial coordinate system as an example for explanation. The direction from the light incident surface 11 to the opposite surface is the X-axis direction, the direction from the first side surface 14 to the opposite surface is the Y-axis direction, and the direction from the reflective surface 13 away from the opposite surface is the Z-axis direction.

Then, the length L in the X-axis direction and the width W in the Y-axis direction of the first microstructure 2 are both in the range of 10um-40um, preferably 20um-30um, and more preferably 25um-30um; the first microstructure 2 is in the Z The length h (ie, depth) in the axial direction is 3um-20um, preferably 10um-20um, more preferably 10um-15um.

Correspondingly, the length and width of the second microstructure 3 in the X-axis direction and the Y-axis direction are both in the range of 5um-20um, preferably 10um-20um, and more preferably 15um-20um; the second microstructure 3 is in the Z The depth in the axial direction is 3um-15um, preferably 3um-10um, more preferably 3um-5um.

In some embodiments, a V-shaped prism structure 4 is provided on the light incident surface 11 .

Specifically, please refer to Figures 9 and 10. A V-shaped prism structure 4 is provided on the light incident surface 11, which can adjust the angular distribution of the light from the light source entering the high splitting ratio light guide plate.

In this embodiment, the V-shaped prism structure 4 is a prism body, a cylindrical lens body, or a mixture of a prism body and a cylindrical lens.

In some embodiments, the refractive index of the light guide plate body 1 is greater than the refractive index of air. For example, the refractive index of the light guide plate body 1 is 1.59.

In some embodiments, the light guide plate body 1 may be composed of a single polymer material, or may be composed of a layered combination of two or more polymer materials.

In some embodiments, the plurality of first microstructures 2 and the light guide plate body 1 are integrated structures, and/or the plurality of second microstructures 3 and the light guide plate body 1 are integrated structures.

In one embodiment, the light guide plate body 1 and the first microstructure 2 are integrally formed with a plastic material, and/or the light guide plate body 1 and the second microstructure 3 are integrally formed with a plastic material, where the plastic material can be polyethylene. Carbonate (PC), polymethylmethacrylate (PMMA), etc.

This application also provides a method for preparing a high splitting ratio light guide plate. Please refer to Figure 11, including:

Step S1: Provide a light guide plate body, which includes a light incident surface and a reflective surface;

Step S2: Provide a light guide plate mold core;

Step S3: Use the light guide plate mold core to form a plurality of first microstructures on the reflective surface of the light guide plate body through nanoimprinting, wherein the first microstructure includes an inclined surface, and the inclined surface faces the entrance Smooth surface, the angle range between the inclined surface and the reflective surface is 27.5°-57.5°.

Based on the above preparation method, the high splitting ratio light guide plate including a plurality of first microstructures described in any of the above embodiments can be prepared.

In this embodiment, one side of the light guide plate mold core has a plurality of protruding structures corresponding to the first microstructure.

In some embodiments, in the method of preparing a high splitting ratio light guide plate, the above step S3 may also be:

Step S3': Use the light guide plate mold core to form a plurality of first microstructures and a plurality of second microstructures on the reflective surface of the light guide plate body through nanoimprinting, wherein the first microstructure includes a bevel. , the inclined surface faces the light incident surface, and the angle range between the inclined surface and the reflective surface is 27.5°-57.5°; the second microstructure includes an arc surface, and the arc surface faces the into the light surface.

Based on the above preparation method, the high splitting ratio light guide plate including a plurality of first microstructures and a plurality of second microstructures described in any of the above embodiments can be prepared.

In this embodiment, one side of the light guide plate mold core has a plurality of protruding structures corresponding to the first microstructure and the plurality of second microstructures.

In some embodiments, the above step S3' includes:

Step S31': Use the light guide plate mold core to form a plurality of first microstructures and a plurality of second microstructures on the reflective surface of the light guide plate body through photocuring molding.

In this embodiment, UV curing may be used for photocuring molding.

Specifically, the above step S1 includes:

Step S11: Provide a base material layer. The base material layer may be composed of a single polymer material, or may be a layered combination of two or more polymer materials;

Step S12: Apply photosensitive glue evenly on the surface of the base material layer to form a photosensitive glue layer, thereby obtaining a light guide plate body. The side of the photosensitive glue layer close to the base material layer is the reflective surface of the light guide plate body.

Specifically, the method of applying the photosensitive glue may be to evenly apply the photosensitive glue on the surface of the base material layer through a coating head.

Further, after the above step S12, step S31' specifically includes:

Use the light guide plate mold to imprint the photosensitive adhesive layer. During imprinting, the side of the light guide plate mold core with the convex structure can be brought into close contact with the photosensitive adhesive layer, and then irradiated with an ultraviolet lamp to make the pattern structure formed on the photosensitive adhesive layer peel off from the light guide plate mold core. Molding, thereby transferring the pattern structure on the surface of the light guide plate mold core to the surface of the base material layer, forming a plurality of first microstructures and a plurality of second structures on the reflective surface of the light guide plate body, and the first microstructure includes a The inclined surface faces the light incident surface, and the angle between the inclined surface and the reflective surface ranges from 27.5° to 57.5°; the second microstructure includes an arc surface, and the arc surface faces the light incident surface.

In other embodiments, the above step S3' includes:

Step S32': Use the light guide plate mold core to form a plurality of first microstructures and a plurality of second microstructures on the reflective surface of the light guide plate body by hot pressing.

Specifically, it includes the following steps:

Step S321': Heat the light guide plate body to soften the reflective surface of the light guide plate body;

Step S322': Imprint the reflective surface of the softened light guide plate body through the light guide plate mold core;

Step S323': Cool and solidify the light guide plate body. The cooled light guide plate body has a plurality of first microstructures and a plurality of second microstructures on the reflective surface side, and the first microstructure includes an inclined surface, and the inclined surface faces the reflective surface. As for the light-incident surface, the angle range between the inclined surface and the reflective surface is 27.5°-57.5°; the second microstructure includes an arc surface, and the arc surface faces the light-incident surface.

In some embodiments, the above step S2 includes:

Step S21: Provide a substrate;

Step S22: Set a plurality of first pits and a plurality of second pits on the substrate to obtain a mold master, wherein the outline of the first pits is the same as the outline of the first microstructure, so The outline of the second pit is the same as the outline of the second microstructure;

Step S23: Perform metal growth and original mold separation on the mold master to obtain the light guide plate mold core.

In some embodiments, the above step S22 includes:

Step S22': Form a plurality of first pits and a plurality of second pits on the substrate through 3D grayscale photolithography to obtain a mold master.

Specifically, it includes the following steps:

Step S221': Provide a first convex topography model and a second convex topography model. The first convex topography model has the same outline as the first microstructure, and the second convex topography model has the same outline as the second microstructure. The outline of the structure is the same;

Step S222': Use laser exposure to produce a photoresist part with a plurality of first microstructures and second microstructures on the glass substrate coated with photoresist, and use metal growth and original mold separation technology to The obtained pattern structure on the photoresisted part is transferred to the metal template to obtain a metal mold core with multiple convex pattern structures.

In some embodiments, the above step S22 includes:

Step S22″: Form a plurality of first pits and a plurality of second pits on the substrate by laser direct writing to obtain the mold master.

In some embodiments, the above step S22 includes:

Step S22''': Use the die head to perform relative movement with the substrate to form a plurality of first pits and a plurality of second pits on the substrate to obtain a mold master.

Specifically, it includes the following steps:

Step S221"': Provide a first convex-morphology diamond die and a second convex-morphology diamond die, wherein the first convex-morphology diamond die has the same profile as the first microstructure, and the second convex-morphology diamond die has the same profile as the first microstructure. The profile of the diamond die is the same as the profile of the second microstructure;

Step S222''': Impact a mold master with a plurality of first pits and a plurality of second pits on the substrate by mechanical impact. Here, the substrate can be a plate made of mirror metal material.

Here, the description will be given as an example of forming a plurality of first dimples on the substrate by using a die head to perform relative motion with the substrate.

Please refer to Figures 12 and 13. For example, if the substrate is a mirror metal plate, the first convex-shaped diamond die 6 (i.e., the diamond cutter head) moves up and down to strike the forming third ridge on the mirror metal plate. The distribution pattern of a microstructure morphology can be the distribution pattern described in any of the above embodiments.

Using the above-mentioned method of mold head impact to form microstructures, corresponding microstructures can be formed through one impact, so that microstructures similar to the die head structure can be formed in one go.

It can be understood that the same method as described above can be used to strike a plurality of second dimples on the substrate through a second convex-shaped diamond die.

Referring to Figure 14, an embodiment of the present invention also provides a light source module, including the high splitting ratio light guide plate described in any of the above embodiments and the light source 5 located on the light incident surface 11 side of the high splitting ratio light guide plate.

Here, the light source 5 may be an LED light-emitting element, and the light emitted by the light source is incident into the high splitting ratio light guide plate through the light incident surface 11 . The wavelength range of the light emitted by the light source 5 is 380nm-780nm.

Please refer to Figure 15. An embodiment of the present invention also provides a display assembly, including the light source module described in any of the above embodiments and a reflective liquid crystal display panel 7. The light source module is located on the reflective liquid crystal display panel 7. the light-emitting side.

Specifically, the reflective liquid crystal display panel 7 is disposed on one side of the light-emitting surface 12 of the light guide plate body 1. The reflective liquid crystal display panel 7 is disposed opposite the light-emitting surface 12 of the light guide plate body 1. During assembly, the light-emitting surface 12 is close to the reflective liquid crystal display. panel 7, so that the light emitted from the light exit surface 12 will be incident on the reflective liquid crystal display panel 7. Furthermore, there may be an adhesive layer or an air layer between the reflective liquid crystal display panel 7 and the light guide plate body 1 .

The display component of the embodiment of the present application is based on a high light splitting ratio light guide plate, and its contrast ratio can be greater than 8:1.

In order to further illustrate the beneficial effects brought by the technical solution of the present application, the beneficial effects of the high splitting ratio light guide plate with the inclined surface 21 of the first microstructure 2 arranged at different angles will be given below based on specific embodiments:

Embodiment 1

The upper surface (ie, the reflective surface 13 ) of the light guide plate body 1 of the high splitting ratio light guide plate has a plurality of irregularly arranged first microstructures 2 . For example: when the first microstructure 2 is a pyramid or a partial pyramid (ie, a pyramid structure), specifically, taking the arrangement of the first microstructure 2 in Figure 8 as an example, the first microstructure 2 in Figure 8 has an orientation facing The inclined surface 21 of the light incident surface 11 (that is, close to the light incident surface 11), the angle between the inclined surface 21 and the reflective surface 13 is α, and the back of the first microstructure 2 faces the light incident surface 11 (that is, away from the light incident surface). 11) The angle between the inclined surface 22 and the reflective surface 13 is β, the length of the base of the pyramid is L, the width is W, and the height of the pyramid is h, where α = 42.5°, β = 80°, W = 20um, L =20um.

Figure 16 is a schematic diagram showing the relationship between the light energy emitted from the reflective surface 13 and the light exit surface 12 of the high splitting ratio light guide plate and the viewing angle. According to FIG. 16 , it can be seen that the light energy distribution emitted from the reflective surface 13 of the high splitting ratio light guide plate has a specific light emission angle peak. At this time, the peak light angle of the reflective surface 13 is emitted at a large angle in the vertical direction (the direction of light propagation in the light guide plate). The peak angle of the emitted light angle is ω=71°, the relative energy of the peak center point is 0.88, and the 0° field of view is 0.25. The light energy from the light-emitting surface is emitted at a small angle, and the energy is concentrated near the front field of view (-5 ~ 25°). The peak angle of the field of view in the vertical direction is θ = 0.9°, and the relative energy of the peak center point is 5.31. Compared with the existing light guide plate, the peak angle of the emitted light is closer to the normal direction of the reflective surface 13 of the light guide plate. At this time, the light output ratio of the entire light output surface 12 and the reflective surface 13 is 9.3:1; the front viewing angle light output ratio is approximately 22:1.

Furthermore, when the size of the angle α between the inclined surface 21 and the reflective surface 13 is changed, the relationship between the different angle values of the angle α between the inclined surface 21 and the reflective surface 13, the split ratio and the light emission angle is as shown in Table 1 below:

Table 1 The relationship between the angle value of the first microstructure and the light splitting ratio and light emission angle

Based on Table 1 above, it can be seen that by adjusting the angle α of the light guide dot microstructure, the peak angle of the light energy emitted from the light guide plate reflective surface 13 and the light exit surface 12, as well as the light exit ratio, can be adjusted to meet different needs. For example, reflective liquid crystals need to emit light as close to the normal line of the light guide plate as possible, such as 0°-20°, and need to have a higher splitting ratio, especially the splitting ratio in the front view field. In this way, the preferred α range is: 32.5°-45°, and the optimum is 35°-43°.

The angle value of microstructure β has little effect on the light emission direction and field of view angle, and does not need to be used as a key control parameter. Therefore, there are no special requirements for the angle of the light guide dot microstructure. The depth and width of the microstructure will affect the intensity of the emitted energy. Since the intensity is also related to the dot density of the light guide plate, it will not be discussed in detail here.

Example 2:

Based on the above embodiment 1, please refer to Figure 17. When the shape of the first microstructure 2 can be a 1/4 cylinder as shown in Figure 17, the range of α is 32.5°-50°, and the range of the depth h is 2um. -20um, the cylinder curvature radius range is 5um-30um.

Specifically, for example, when α=42.5°, depth h=9um, cylinder curvature radius R=18um, the light guide plate base material PC has a thickness of 0.4mm. For a high splitting ratio light guide plate with the first microstructure 2 having the above morphology, when light is coupled from the light incident surface 11, the relationship between the light energy emitted from the reflective surface 13 and the light exit surface 12 and the viewing angle is as shown in Figure 18 Show.

As shown in Figure 18, the peak light angle of the reflective surface 13 is emitted at a large angle in the vertical direction (the direction of light propagation in the light guide plate). The peak angle of the emitted light angle is ω = 73°, and the half-peak width of the full field of view is 92 °. The light energy from the light-emitting surface is emitted at a small angle. The peak angle of the emitted light field of view in the vertical direction is θ = 0.9°, and the half-peak width of the full field of view is 47°. The light output ratio of the entire light output surface 12 and the reflective surface 13 is 9:1; the light energy split ratio at the front viewing angle is approximately 22:1.

Embodiment three:

As described in Embodiment 1, please refer to Figure 19A. When the shape of the first microstructure 2 can be a 1/8 sphere as shown in Figure 19A, where the range of α is 32.5°-50°, and the range of depth h is The range is 2um-20um, and the radius of curvature of the sphere is 5um-30um.

Specifically, for example, when α=42.5°, depth h=6um, and spherical curvature radius R=18um, the light guide plate base material PC has a thickness T=0.4mm. For a high splitting ratio light guide plate with the first microstructure 2 having the above morphology, when light is coupled from the light incident surface 11, the relationship between the light energy emitted from the reflective surface 13 and the light exit surface 12 and the viewing angle is as shown in Figure 20 Show.

Understandably, the morphology of the first microstructure 2 can also be the structure shown in Figure 19B. Please refer to Figure 19B. In this structure, the range of α is 32.5°-50°, the range of the depth h is 2um-20um, and the sphere The curvature radius range is 5um-30um.

As shown in FIG. 20 , the peak light angle of the reflective surface 13 is emitted at a large angle in the vertical direction, and the peak angle of the light emission angle is ω = 73°. The light energy from the light-emitting surface is emitted at a small angle. The peak angle of the emitted light field of view in the vertical direction is θ = 0°, and the half-peak width of the full field of view is 33°. The light output ratio of the entire light output surface 12 and the reflective surface 13 is 9:1; the light energy split ratio at the front viewing angle is approximately 22:1.

Embodiment 4:

As described in Embodiment 1, please refer to Figure 21. When the shape of the first microstructure 2 can be a 1/8 cylinder as shown in Figure 21, the range of α is 32.5-50°, and the range of the depth h is 2 -20um, the cylinder curvature radius range is 5-30um. Specifically, for example, when α=42°, depth h=um, and cylinder curvature radius R=18um, the light guide plate base material PC has a thickness T=0.4mm. For a high splitting ratio light guide plate with the first microstructure 2 having the above morphology, when light is coupled from the light incident surface 11, the relationship between the light energy emitted from the reflective surface 13 and the light exit surface 12 and the viewing angle is as shown in Figure 22 Show.

As shown in FIG. 22 , the peak light emission angle of the reflective surface 13 is emitted at a large angle in the vertical direction (the direction of light propagation in the light guide plate), and the peak light emission angle is ω = 73°. The light energy from the light-emitting surface is emitted at a small angle. The peak angle of the emitted energy is θ = 0.9° in the vertical field of view, and the half-peak width of the full field of view is 34°. The light output ratio of the entire light output surface 12 and the reflective surface 13 is 8.5:1; the light energy split ratio at the front viewing angle is 20:1.

Embodiment five:

As described in Embodiment 1, please refer to Figure 23. When the shape of the second microstructure 3 can be a 1/2 cylindrical structure as shown in Figure 23, it is different from the 1/2 cylindrical structure in Embodiment 2. The cylindrical structure is placed horizontally, where the depth h ranges from 2um-20um, the cylinder curvature radius R ranges from 5um-30um, and the width range w ranges from 32.5°-50°

Specifically, for example, when R=15um, depth h=9um, w=20um, light guide plate base material PC, thickness T=0.4mm. For a high splitting ratio light guide plate with the first microstructure 2 having the above morphology, when light is coupled from the light incident surface 11, the relationship between the light energy emitted from the reflective surface 13 and the light exit surface 12 and the viewing angle is as shown in Figure 24 Show.

As shown in Figure 24, the peak light angle of the reflective surface 13 is emitted at a large angle in the vertical direction (the direction of light propagation in the light guide plate). The peak angle of the emitted light angle is ω = 71°, and the half-peak width of the full field of view is 98 °. The light energy from the light-emitting surface is emitted at a small angle. The peak angle of the emitted energy in the vertical field of view is θ = 22.5°, and the half-peak width of the full field of view is 98°. The light-emitting ratio of the entire light-emitting surface 12 and the reflective surface 13 is 2.5:1; the light-emitting energy at the front viewing angle is relatively large. Due to the large exit angle peak width, the hot spot effect of the LED at the incident light can be effectively reduced.

Embodiment 6:

Please refer to Figure 25. When the morphology of the second microstructure 3 can be a spherical crown structure as shown in Figure 25, the depth h ranges from 2um to 20um, and the cylinder curvature radius R ranges from 5um to 30um.

Specifically, for example, R=15um, depth 9um, light guide plate base material PC, thickness T=0.4mm. For a high splitting ratio light guide plate with the second microstructure 3 having the above morphology, when light is coupled from the light incident surface 11, the relationship between the light energy emitted from the reflective surface 13 and the light exit surface 12 and the viewing angle is as shown in Figure 26 Show.

As shown in Figure 26, the peak light angle of the reflective surface 13 is emitted at a large angle in the vertical direction (the direction of light propagation in the light guide plate). The peak angle of the emitted light angle is ω = 75°, and the half-peak width of the full field of view is 167 °. The peak angle of the effective light-emitting energy of the light-emitting surface 12 in the vertical direction is θ=31.5°, and the full-viewing-angle half-peak width is 98°. Due to the large exit angle peak width, the hot spot effect of the LED at the incident light can be effectively reduced.

Compared with the existing technology, the first microstructure provided by this application can effectively control the light emission angle of the light guide plate and the light splitting ratio of the upper and lower surfaces of the light guide plate, so that the light emission ratio of the effective light emission surface and the ineffective reflective surface of the light guide plate is approximately 10: 1. At the same time, the direction of the light emitted from the effective light emitting surface and the ineffective reflective surface can be adjusted so that the peak angle of the emitted light from the effective light emitting surface is between 0° and 20°, and the peak angle of the emitted light from the ineffective light emitting surface is greater than 50°, thus effectively improving the entry display. The light energy of the panel will not only improve the energy utilization of the light source, but also improve the contrast of the reflective liquid crystal display device, especially the contrast of the front view field; the light guide efficiency of the first microstructure of the slope is high, close to the light entrance Setting a lower-density first microstructure and adding a second microstructure such as a recess with a smaller size, due to its low light guide efficiency and wide distribution of outgoing light direction, combined with the first microstructure can effectively reduce the front The hot spot or light spot phenomenon of the light module near the LED light bar improves the quality of the screen display.

Reference example:

In this reference example, when the angular range of the angle α between the inclined surface 21 and the reflective surface 13 is changed to not within the angle range of 27.5°-57.5°, the angle values and light splitting ratios of different angle α between the inclined surface 21 and the reflective surface 13 The relationship between the angle and the light emission angle is shown in Table 2 below:

Table 2 The relationship between the angle value of the first microstructure and the light splitting ratio and light emission angle

According to Table 2 above, it can be seen that when the angle α between the inclined surface 21 and the reflective surface 13 is within the angle range of 15-25° and 65°-75°, the light splitting ratio of the light guide plate is less than 4:1.

Further, please refer to FIG. 27A to FIG. 27D , which are schematic diagrams showing the relationship between the effective light extraction and the ineffective light extraction of the high splitting ratio light guide plate and the viewing angle respectively when the angle α between the inclined surface 21 and the reflective surface 13 is shown. Among them, in FIG. 27A , α=15°; in Figure 27B, α=20°; in Figure 27C, α=70°; in Figure 27D, α=75°.

According to Figure 27A and Figure 27B, it can be seen that when α=15° or 20°, the effective peak light emission angle of the high splitting ratio light guide plate is greater than 30°, and in the range of -5°-25° in the front field of view, its light intensity is close to It is 0, which cannot meet the usage requirements of reflective LCD displays.

According to Figure 27C and Figure 27D, it can be seen that when α = 70° or 75°, the effective light emission peak angle of the high splitting ratio light guide plate is outside -30°, and in the range of -5°-25° in the front field of view, its The light intensity is very weak and cannot meet the requirements of reflective LCD displays.

As used herein, the terms "includes," "comprises," or any other variation thereof are intended to cover a non-exclusive inclusion of elements other than those listed and may also include other elements not expressly listed.

In this article, the front, back, upper, lower and other locative words involved are defined based on the location of the components in the drawings and the positions of the components relative to each other, just for the sake of clarity and convenience in expressing the technical solution. It should be understood that the use of the locative words shall not limit the scope of protection claimed in this application.

The above-described embodiments and features in the embodiments herein may be combined with each other if there is no conflict. The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection of the present invention. within the range.

Claims

A high light splitting ratio light guide plate, characterized in that it is applied to the light exit side of a reflective liquid crystal display panel, including:

The light guide plate body includes a light incident surface, a light emergent surface and a reflective surface. The light incident surface and the light emergent surface are arranged oppositely, and the light incident surface is connected to the reflective surface and the light emergent surface respectively;

A plurality of first microstructures are recessed inwardly on the reflective surface. Each of the first microstructures includes an inclined surface, and the inclined surface faces the light incident surface. The inclined surface The angle between the reflective surface and the reflective surface ranges from 27.5° to 57.5°, so that the ratio of the effective light output energy of the light output surface of the high splitting ratio light guide plate to the ineffective light output energy of the reflective surface is between 5:1-10 : 1, and the ratio of the effective light-emitting energy of the light-emitting surface of the high-splitting-ratio light guide plate to the ineffective light-emitting energy of the reflective surface within the front field of view ranges from 10:1 to 22:1.
The high splitting ratio light guide plate according to claim 1, further comprising:

A plurality of second microstructures are recessed inwardly on the reflective surface. Each of the second microstructures includes an arc surface, and the arc surface faces the light incident surface.
The high splitting ratio light guide plate according to claim 1, wherein the angle between the inclined surface of the first microstructure and the reflective surface is 32.5°-45°.
The high splitting ratio light guide plate according to claim 1, wherein the first microstructure is one or more of a pyramid, a prism, a partial sphere and a partial cylinder.
The high splitting ratio light guide plate according to claim 1, wherein the inclined surface of the first microstructure is an optically smooth surface, and the roughness Ra of the inclined surface is 30 nm-150 nm.
The high splitting ratio light guide plate according to claim 1 or 2, characterized in that the first spacing between any two adjacent first microstructures varies with the two adjacent first microstructures. The first average distance from the structure to the light incident surface decreases with the increase, and the first spacing and the first average distance satisfy the requirement that the first average distance is used as an independent variable, and the first spacing is the exponential function relationship of the dependent variable.
The high splitting ratio light guide plate according to claim 2, characterized in that a plurality of the second microstructures are provided in a preset area, and the preset area is from the light incident surface to the reflective surface. The area away from the 1/3-1/2 of the light incident surface.
The high splitting ratio light guide plate according to claim 2, wherein the second microstructure is one or more of a hemispherical shape, a cylindrical shape, a water drop shape and a horseshoe shape.
The high splitting ratio light guide plate according to claim 1, wherein the length and width of the first microstructure are both in the range of 10um-40um.
The high splitting ratio light guide plate according to claim 1, wherein the depth of the first microstructure ranges from 3um to 20um.
The high splitting ratio light guide plate according to claim 2, wherein the length and width of the second microstructure are both in the range of 5um-20um.
The high splitting ratio light guide plate according to claim 2, wherein the depth of the second microstructure ranges from 3um to 15um.
The high splitting ratio light guide plate according to claim 2, wherein the second spacing between any two adjacent second microstructures varies from the range of the two adjacent second microstructures to The second average distance of the light incident surface increases with the increase, and the second spacing and the average distance satisfy the requirement that the second average distance is an independent variable and the second distance is a dependent variable. exponential function relationship.
The high splitting ratio light guide plate according to claim 1 or 2, characterized in that a V-shaped prism structure is provided on the light incident surface.
The high splitting ratio light guide plate according to claim 14, wherein the V-shaped prism structure is a prism body, a cylindrical lens body, or a mixture of a prism body and a cylindrical lens.
A method for preparing a high splitting ratio light guide plate, which is characterized by including:

Provide a light guide plate body, the light guide plate body includes a light incident surface and a reflective surface;

Provide a light guide plate mold core;

The light guide plate mold core is used to form a plurality of first microstructures on the reflective surface of the light guide plate body through nanoimprinting, wherein the first microstructure includes an inclined surface, and the inclined surface faces the light incident surface, The angle range between the inclined surface and the reflective surface is 27.5°-57.5°.
The method for preparing a high splitting ratio light guide plate according to claim 16, further comprising:

The light guide plate mold core is used to form a plurality of second microstructures on the reflective surface of the light guide plate body through nanoimprinting, wherein the second microstructure includes an arc surface, and the arc surface faces the incident light. noodle.
The method for preparing a high splitting ratio light guide plate according to claim 17, characterized in that:

The use of the light guide plate mold core to form a plurality of first microstructures on the reflective surface of the light guide plate body through nanoimprinting includes:

Use the light guide plate mold core to form a plurality of first microstructures on the reflective surface of the light guide plate body through photocuring molding;

and / or,

The light guide plate mold core is used to form a plurality of second microstructures on the reflective surface of the light guide plate body through nanoimprinting, including:

The light guide plate mold core is used to form a plurality of second microstructures on the reflective surface of the light guide plate body through photocuring molding.
The method for preparing a high splitting ratio light guide plate according to claim 17, characterized in that:

The use of the light guide plate mold core to form a plurality of first microstructures on the reflective surface of the light guide plate body through nanoimprinting includes:

Use the light guide plate mold core to form a plurality of first microstructures on the reflective surface of the light guide plate body by hot pressing; and/or,

The light guide plate mold core is used to form a plurality of second microstructures on the reflective surface of the light guide plate body through nanoimprinting, including:

The light guide plate mold core is used to form a plurality of second microstructures on the reflective surface of the light guide plate body through photocuring molding.
The method for preparing a high splitting ratio light guide plate according to claim 17, wherein said providing a light guide plate mold core includes:

providing a substrate;

A plurality of first pits and/or a plurality of second pits are provided on the substrate to obtain a mold master, wherein the outline of the first pits is the same as the outline of the first microstructure, and the The outline of the second pit is the same as the outline of the second microstructure;

The mold master is subjected to metal growth and original mold separation to obtain the light guide plate mold core.
The method for preparing a high splitting ratio light guide plate according to claim 20, wherein said setting a plurality of first pits and/or a plurality of second pits on the substrate to obtain a mold master includes: :

A plurality of first pits and/or a plurality of second pits are formed on the substrate through 3D grayscale photolithography to obtain the mold master.
The method for preparing a high splitting ratio light guide plate according to claim 20, wherein said setting a plurality of first pits and/or a plurality of second pits on the substrate to obtain a mold master includes: :

A plurality of first pits and/or a plurality of second pits are formed on the substrate by laser direct writing to obtain the mold master.
The method for preparing a high splitting ratio light guide plate according to claim 20, wherein said setting a plurality of first pits and/or a plurality of second pits on the substrate to obtain a mold master includes: :

The mold master is obtained by using a die head to perform relative movement with the substrate to form a plurality of first pits and/or a plurality of second pits on the substrate.
A light source module, characterized by comprising the high splitting ratio light guide plate according to any one of claims 1 to 15 and a light source located on the light incident surface side of the high splitting ratio light guide plate.
A display assembly, characterized by comprising the light source module as claimed in claim 24 and a reflective liquid crystal display panel, the light source module being located on the light emitting side of the reflective liquid crystal display panel.