WO2022252736A1

WO2022252736A1 - Composite optical film and display device

Info

Publication number: WO2022252736A1
Application number: PCT/CN2022/080245
Authority: WO
Inventors: 邓天应; 陈细俊; 季洪雷; 许怀书; 宋庆欢
Original assignee: 惠州视维新技术有限公司
Priority date: 2021-05-31
Filing date: 2022-03-10
Publication date: 2022-12-08
Also published as: CN215932185U

Abstract

A composite optical film and a display device. The composite optical film comprises a first lens layer (101), a first substrate layer (102), a laminating adhesive layer (103), a second lens layer (104), a second substrate layer (105), and a back coating (106). The first substrate layer (102) and the second lens layer (104) are bonded by means of the laminating adhesive layer (103). The first lens layer (101) comprises a plurality of first triangular prisms (1011). The second lens layer (104) comprises a plurality of second triangular prisms (1041). An included angle at a peak tip of the first triangular prisms (1011) is greater than an included angle at a peak tip of the second triangular prisms (1041).

Description

Composite optical film and display device

This application claims the priority of the Chinese patent application with the application number 202121203376.4 and the patent name "Composite Optical Film and Display Device" filed with the China Patent Office on May 31, 2021, the entire contents of which are hereby incorporated by reference in this application .

technical field

The present application relates to the field of display technology, in particular to a composite optical film and a display device.

Background technique

Liquid crystal display (Liquid Crystal Display, LCD) is currently the most common display technology. The backlight module is an important part of the liquid crystal display, and its main function is to provide a high-brightness and uniform surface light source for the liquid crystal display panel of the liquid crystal display. In order to ensure the picture quality of the liquid crystal module, multiple optical films must be used in the backlight module, such as prism film, diffusion film, microlens film, etc.

With the development of LCD display technology, the number of optical films in the backlight module has evolved from the traditional four or three to the current mainstream two. However, the two brightness-enhancing films in the existing backlight module are composite films bonded together by glue, which cannot be applied to the display alone, and must be used with an optical film on the top and bottom of the composite film, which cannot meet the ultimate product requirements. The demand for simple and extreme design and assembly process. However, simply integrating the two brightness enhancement films in the existing backlight module into one composite film will cause problems due to the matching angle of the optical films on the upper and lower sides, the prism structure of each optical film, the haze of the prism and The mutual influence of the data parameters such as the glue characteristics coated by the composite film may easily lead to the optical brightness and the optical performance index of the viewing angle of the composite film not reaching the standard, causing the display to have a mirror image effect on the visual effect.

technical problem

The embodiment of the present application provides a composite optical film and a display device. The composite optical film can replace the two optical films in the existing backlight module and be applied to the display separately, thereby solving the problem of using two optical films in the backlight module. When stretching the brightness enhancement film, it is easy to have the problem that the optical performance index does not meet the standard, so as to improve the optical performance of the backlight module.

technical solution

In the first aspect, the embodiment of the present application provides a composite optical film, the composite optical film includes from top to bottom:

a first lens layer, the first lens layer comprising a plurality of first triangular prisms arranged horizontally and parallel to each other;

a first substrate layer;

Adhesive layer;

The second lens layer, the first substrate layer and the second lens layer are bonded by the adhesive layer, and the second lens layer includes a plurality of second triangular prisms placed horizontally and parallel to each other, so The angle at the peak of the first triangular prism is greater than the angle at the peak of the second triangular prism;

a second substrate layer; and

back coating.

In the composite optical film, the adhesive layer has a thickness of 2 micrometers to 5 micrometers and a refractive index of 1.49-1.56.

In the composite optical film, the bonding adhesive layer contains diffusion particles, and the doping ratio of the diffusion particles in the bonding adhesive layer is 1%-6%.

In the composite optical film, the back coating contains the diffusion particles, and the diffusion particles include silicon dioxide, titanium dioxide, polymethyl methacrylate, and poly-n-butyl methacrylate.

In the composite optical film, the included angle at the peak of the first triangular prism is 90°-100°, and the included angle at the peak of the second triangular prism is 85°-90°.

In the composite optical film, the distance between the peaks of two adjacent first triangular prisms is smaller than the distance between the peaks of two adjacent second triangular prisms;

The height of the first triangular prism is smaller than the height of the second triangular prism.

In the composite optical film, the included angle between the first extension direction of the first triangular prism on the horizontal plane and the second extension direction of the second triangular prism on the horizontal plane is at least greater than 60°.

In the composite optical film, the composite optical film also includes a first glue layer and a second glue layer, the first lens layer is bonded to the first substrate layer through the first glue layer , the second lens layer is bonded to the second substrate layer through the second glue layer;

The refractive index of the first glue layer and/or the second glue layer is 1.53-1.56.

In the composite optical film, the haze of the back coating is 3%-25%.

In a second aspect, in order to solve the above-mentioned technical problems, the embodiments of the present disclosure further provide a display device, including a backlight module, and the backlight module includes any one of the composite optical films described above.

In the display device, the adhesive layer has a thickness of 2 microns-5 microns and a refractive index of 1.49-1.56.

In the display device, the bonding adhesive layer contains diffusion particles, and the doping ratio of the diffusion particles in the bonding adhesive layer is 1%-6%.

In the display device, the back coat contains the diffusion particles, and the diffusion particles include silicon dioxide, titanium dioxide, polymethyl methacrylate, poly-n-butyl methacrylate.

In the display device, the included angle at the apex of the first triangular prism is 90°-100°, and the included angle at the apex of the second triangular prism is 85°-90°.

In the display device, the distance between the peaks of two adjacent first triangular prisms is smaller than the distance between the peaks of two adjacent second triangular prisms;

In the display device, the included angle between the first extension direction of the first triangular prism on the horizontal plane and the second extension direction of the second triangular prism on the horizontal plane is at least greater than 60°.

In the display device, the composite optical film further includes a first glue layer and a second glue layer, the first lens layer is bonded to the first substrate layer through the first glue layer, so The second lens layer is bonded to the second substrate layer through the second glue layer;

In the display device, the glue used in the first glue layer, the second glue layer, and the bonding glue layer includes resin glue.

In the display device, the haze of the back coating is 3%-25%.

Beneficial effect

The composite optical film provided in this embodiment includes: a first lens layer, a first base material layer, an adhesive layer, a second lens layer, a second base material layer and a back coat layer, the first base material layer and the second base material layer. The lens layers are bonded by a bonding adhesive layer, the first lens layer includes a plurality of first triangular prisms, the second lens layer includes a plurality of second triangular prisms, and the included angle at the peak of the first triangular prism is larger than that of the peaks of the second triangular prism. Angle at the tip. Setting the angle at the peak of the first triangular prism to be greater than the angle at the peak of the second triangular prism can improve the optical brightness index and the optical viewing angle index of the composite optical film, thereby improving the optical performance of the composite optical film. At the same time, Applying the composite optical film provided by this application to the display instead of the two optical films in the existing backlight module can solve the problem that the optical performance index is not up to standard when two brightness enhancement films are used in the backlight module , thereby improving the optical performance of the backlight module.

Description of drawings

The technical solutions and other beneficial effects of the present application will be apparent through the detailed description of the specific embodiments of the present application below in conjunction with the accompanying drawings.

FIG. 1 is a schematic structural diagram of a composite optical film provided by an embodiment of the present disclosure;

Fig. 2 is a schematic top view structural view of an angular relationship between the first extension direction of the first triangular prism on the horizontal plane and the second extension direction of the second triangular prism on the horizontal plane provided by an embodiment of the present disclosure.

Explanation of reference numbers

The first lens layer 101, the first substrate layer 102, the adhesive layer 103, the second lens layer 104, the second substrate layer 105, the back coating layer 106, and the diffusion particles 107;

The first triangular prism 1011, the second triangular prism 1041;

The height H ₁ of the first triangular prism 1011, the height H ₂ of the second triangular prism 1041, the distance P ₁ between the peaks of two adjacent first triangular prisms 1011, the peaks of two adjacent second triangular prisms 1041 The pitch P ₂ between them, the angle α between the first extending direction of the first triangular prism 1011 on the horizontal plane and the second extending direction of the second triangular prism 1041 on the horizontal plane.

Detailed ways

The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Apparently, the described embodiments are only some of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without making creative efforts belong to the scope of protection of this application.

In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", " Orientation indicated by rear, left, right, vertical, horizontal, top, bottom, inside, outside, clockwise, counterclockwise, etc. The positional relationship is based on the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the application and simplifying the description, and does not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, Therefore, it should not be construed as limiting the application. In the description of the present application, "plurality" means two or more, unless otherwise specifically defined.

In the description of this application, it should be noted that unless otherwise specified and limited, the terms "installation", "connection", and "connection" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection. Connected, or integrally connected; it can be mechanically connected, or electrically connected, or can communicate with each other; it can be directly connected, or indirectly connected through an intermediary, and it can be the internal communication of two components or the interaction of two components relation. Those of ordinary skill in the art can understand the specific meanings of the above terms in this application according to specific situations.

To simplify the disclosure of the present application, components and arrangements of specific examples are described below. Of course, they are examples only and are not intended to limit the application. Furthermore, the present application may repeat reference numerals and/or reference letters in various instances, such repetition is for simplicity and clarity and does not in itself indicate a relationship between the various embodiments and/or arrangements discussed. In addition, various specific process and material examples are provided herein, but one of ordinary skill in the art may recognize the use of other processes and/or the use of other materials.

Please refer to Figure 1 and Figure 2, Figure 1 is a schematic structural view of a composite optical film provided by an embodiment of the present disclosure, Figure 2 is the first extension direction of the first triangular prism provided by an embodiment of the present disclosure on the horizontal plane, and A schematic top view of the structure of the second triangular prism on the horizontal plane with an angular relationship in the second extension direction, as shown in Figures 1 and 2, an embodiment of the present disclosure provides a composite optical film, the composite optical film is from top to bottom The bottom layer includes: first lens layer 101, first base material layer 102, bonding adhesive layer 103, second lens layer 104, second base material layer 105 and back coating layer 106, wherein, first base material layer 102 and The second lens layer 104 is bonded by the adhesive layer 103, and the first lens layer 101 includes a plurality of first triangular prisms 1011 placed horizontally and parallel to each other (in FIG. Only one first triangular prism 1011 is shown), the second lens layer 104 includes a plurality of second triangular prisms 1041 placed horizontally and parallel to each other, the angle at the apex of the first triangular prism 1011 is larger than the peak of the second triangular prism 1041 Angle at the tip.

It should be noted that by setting the structure of the prisms on the first lens layer 101 and the second lens layer 104 as a plurality of triangular prisms placed horizontally and parallel to each other, the microstructures of the first lens layer 101 and the second lens layer 104 A dithering structure is formed to optimize the angle of light emitted by the light source, thereby improving the optical brightness of the composite optical film provided in the present disclosure.

Further, by setting the angle included at the peak of the first triangular prism 1011 to be greater than the angle included at the peak of the second triangular prism 1041, the angle of the light emitted by the light source can be contracted, and the central brightness can be improved, thereby increasing the cost of the light source. The light guide efficiency of the composite optical film provided by the disclosure makes the composite optical film have better optical brightness and makes the brightness of the final display picture more uniform.

In some embodiments, the lower surface of the first substrate layer 102 is provided with a back coating (not shown in the figure), and the above-mentioned adhesive layer 103 is coated on the back coating layer. 102, the back coat layer provided on the lower surface is coated with an adhesive layer 103, so that the first substrate layer 102 is bonded to the upper surface of the second lens layer 104, thereby constituting the compound optical film provided by the embodiment of the present disclosure. Composite structure.

In order to improve the optical performance of the composite optical film provided by the embodiment of the present disclosure, in one embodiment of the present disclosure, please continue to refer to FIG. 1 and FIG. 2 , the distance between the peaks of two adjacent first triangular prisms 1011 P ₁ , less than the pitch P ₂ between the peaks of two adjacent second triangular prisms 1041, the height H ₁ of the first triangular prism 1011 is less than the height H ₂ of the second triangular prism 1041, and the first triangular prism 1011 is on the horizontal plane The angle α between the first extending direction of the second triangular prism 1041 and the second extending direction of the second triangular prism 1041 on the horizontal plane is at least greater than 60°.

Since there is a certain angle between the first extension direction of the first triangular prism 1011 on the horizontal plane and the second extension direction of the second triangular prism 1041 on the horizontal plane, the included angle between the first extension direction and the second extension direction α is set to be at least greater than 60°, and there is a preset angle relationship between the first extending direction and the second extending direction, which can effectively improve the optical performance index of the composite optical film.

Specifically, please continue to refer to FIG. 2 . FIG. 2 only shows the first extension direction of the first triangular prism 1011 on the horizontal plane, and a preset relationship between the second extension direction of the second triangular prism 1041 on the horizontal plane. Angle relationship, as shown in Figure 2, Figure 2 shows the Cartesian coordinate system of the horizontal plane, and the first extension direction of the first triangular prism 1011 on the horizontal plane is based on the X axis, and the O point is the center of the circle to rotate clockwise 87 The direction after °, the second extension direction of the second triangular prism 1041 on the horizontal plane is the direction after the X-axis is taken as the standard, and the center of the circle is rotated counterclockwise by -5° at point O.

As a preferred embodiment of the present disclosure, as shown in the following table, the present disclosure provides various embodiments in which the first extending direction and the second extending direction have a preset angle relationship, wherein, the first extending direction and the second extending direction exist Different angle relationships can achieve different effects, such as when the first extension direction and the second extension direction meet the angle relationship shown in Example 5 in the table below, that is, the first extension direction is 87°~93°, and the second extension direction When the direction is -5°~5°, the brightness gain of the composite optical film can be maximized at this time. For another example, when the first extending direction and the second extending direction meet the angular relationship shown in Example 2 in the table below, that is, when the first extending direction is 40°~50° and the second extending direction is 130°~140°, the The horizontal viewing angle range of the composite optical film can be maximized at the same time. Therefore, through the different relationships between the first extension direction and the second extension direction provided by the application, the optimal solution can be selected according to actual needs, thereby obtaining a variety of Products with different positioning to meet users with different needs.

项目 project	第一延伸方向 first extension direction	第二延伸方向 Second extension direction	亮度增益（相比现有技术） Brightness gain (compared to existing technology)	视角范围（水平/垂直） Angle of view (Horizontal and vertical)
实施例1 Example 1	-5°~5° -5°~5°	87°~93° 87°~93°	100% 100%	70/65 70/65
实施例2 Example 2	40°~50° 40°~50°	130°~140° 130°~140°	100% 100%	75/68 75/68
实施例3 Example 3	10°~17° 10°~17°	90°~95° 90°~95°	100% 100%	72/66 72/66
实施例4 Example 4	-3°~3° -3°~3°	72°~77° 72°~77°	100% 100%	73/64 73/64
实施例5 Example 5	87°~93° 87°~93°	-5°~5° -5°~5°	104% 104%	68/74 68/74
实施例6 Example 6	130°~140° 130°~140°	40°~50° 40°~50°	103% 103%	70/73 70/73
实施例7 Example 7	90°~95° 90°~95°	10°~17° 10°~17°	103% 103%	70/75 70/75
实施例8 Example 8	72°~77° 72°~77°	-3°-3° -3°-3°	103.5% 103.5%	66/70 66/70

In order to further improve the optical performance of the composite optical film, in another embodiment of the present disclosure, the specific height _H1 of the first triangular prism 1011 is 15 microns to 25 microns, and the clip at the tip of the first triangular prism 1011 is The angle is 90°-100°, the pitch _P1 between the peaks of two adjacent first triangular prisms 1011 is 20 microns to 40 microns; the height H ₂ of the second triangular prisms 1041 is 35 microns to 50 microns, the second The included angle at the peaks of the triangular prisms 1041 is 85°-90°, and the distance P ₂ between the peaks of two adjacent second triangular prisms 1041 is 60 microns to 70 microns.

In practical applications, the height H ₁ of the first triangular prism 1011 and the height H ₂ of the second triangular prism 1041 are usually fixed values, but in order to meet different application requirements, the height H 1 of the first triangular prism 1011 and the height H ₂ of the second triangular prism 1041 The height _H of two triangular prisms 1041 also can be unfixed numerical value, promptly a plurality of first triangular prisms 1011 or a plurality of second triangular prisms 1041 can be arranged at the same height, also can not be arranged with equal heights, as long as the first triangular prisms 1011 The height _H1 of the second triangular prism 1041 and the height _H2 of the second triangular prism 1041 are within the height range defined in the above-mentioned embodiments.

In this embodiment, the composite optical film further includes a first glue layer (not shown in the figure) and a second glue layer (not shown in the figure), and the first lens layer 101 is connected to the first substrate through the first glue layer. material layer 102, and the second lens layer 104 is bonded to the second substrate layer 105 through the second glue layer, wherein the glue used in the first glue layer and the second glue layer can be resin glue, and those skilled in the art will also The appropriate glue can be selected as the bonding material according to the actual situation.

In order to make the composite optical film have better optical brightness, in the embodiment of the present disclosure, the back coating haze of the first lens layer 101 is 20% to 40%, and the back coating haze of the second lens layer 104 is 3%. To 25%, the refractive index of the first glue layer and/or the second glue layer is 1.53-1.56. It should be noted that the refractive index of the glue layer generally refers to the refractive index of the glue before curing, and the index that can be detected is also the index before curing. The refractive index of the liquid.

In the embodiment of the present disclosure, the thickness of the bonding adhesive layer 103 in the composite optical film is 2 microns-5 microns, and the refractive index is 1.49-1.56. Preferably, the glue used for the bonding adhesive layer 103 is resin glue.

In order to better control the mirror effect on the visual effect, a certain proportion of tiny diffusion particles 107 is added to the adhesive layer 103 .

Specifically, the diffusion particles 107 include one or more of silicon dioxide, titanium dioxide, polymethyl methacrylate, and poly-n-butyl methacrylate, any one or more types of diffusion particles 107 above The total doping ratio in the adhesive layer 103 is 1%-6%.

In this embodiment, the haze of the back coat 106 under the second substrate layer 105 in the composite optical film is set to 3% to 25%. In order to further improve the optical performance of the composite optical film, the back coat Diffusion particles 107 are also added to layer 106 .

In addition, in another embodiment of the present disclosure, the thickness of the first substrate layer 102 and the thickness of the second substrate layer 105 in the composite optical film are both 125 microns to 250 microns.

In practical applications, the thicknesses of the first base material layer 102 and the second base material layer 105 are usually the same thickness, but those skilled in the art can also select appropriate and different thicknesses as the first base material layer 102 according to the actual situation. and the thickness of the second base material layer 105, as long as the thicknesses of the first base material layer 102 and the second base material layer 105 are within the thickness range defined in the above-mentioned embodiments.

Wherein, the material of any one of the base material layers is selected from one or more of PET (polyethylene terephthalate), PE (polyethylene) and PEN (polyethylene terephthalate).

In a preferred embodiment of the present disclosure, this embodiment provides a backlight module, the backlight module includes a composite optical film, and the composite optical film is the composite optical film in any of the above embodiments.

Since the backlight module provided by the present disclosure includes the above-mentioned composite optical film, it is not necessary to use an optical film on the top and bottom of each brightness enhancement sheet like the existing two brightness enhancement sheets, so that it can be used from In the backlight module, the existing two brightening sheets are discarded and replaced by the composite optical film provided by the present disclosure, so that the backlight module of the present disclosure not only has better optical performance, but also can meet the current product extreme The demand for simple and extreme design and assembly process.

Since the backlight module includes the composite optical film in any of the above embodiments, it can realize the beneficial effects that the composite optical film can achieve in any of the above embodiments.

In another preferred embodiment of the present disclosure, this embodiment provides a display device, the display device includes a backlight module, and the backlight module is the backlight module provided in the above embodiments.

Since the backlight module provided by the above-mentioned embodiments includes the composite optical film in any of the above-mentioned embodiments, the display device provided by the embodiments of the present disclosure can also use the first extension direction of the first triangular prism and the second three The setting of the different relationship between the second extending direction of the prism can realize the selection of the display device with the best optical performance according to the actual needs of users, so that a variety of products with different positioning can be obtained, and users with different needs can be satisfied.

Since the display device includes the backlight module provided by the above-mentioned embodiment, it can realize the beneficial effects that the backlight module provided by the above-mentioned embodiment can achieve, and because the backlight module provided by the above-mentioned embodiment includes any of the above-mentioned embodiments. The composite optical film, therefore, the display device can achieve the beneficial effects that the composite optical film can achieve in any of the above-mentioned embodiments.

From the above description, it can be seen that the above embodiments provided by the present disclosure achieve the following technical effects:

1. By optimizing the microstructure of the lens layer, the thickness of the substrate layer, the angle at the peak of the triangular prism, the distance between two adjacent peaks, the height of the triangular prism, and the haze of the back coating The combination of design can not only make the composite optical film of the present disclosure have better optical performance, but also can control the mirror effect on the visual effect, so that the composite optical film of the present disclosure can replace the existing backlight module Two commonly used brightening sheets.

2. By adding a certain proportion of tiny diffusion particles to the adhesive layer to disperse the internal light transmission at multiple angles, the mirror effect on the visual effect can be further controlled.

3. By setting the first extension direction of the first triangular prism on the horizontal plane and the second extension direction of the second triangular prism on the horizontal plane to a preset angle relationship, the optimal solution can be selected according to actual needs, thereby being able to Get a variety of products with different positioning to meet users with different needs.

4. Since the backlight module of the present disclosure includes the above-mentioned composite optical film, it is not necessary to use an optical film on the top and bottom of each brightness-enhancing sheet like the existing two brightness-enhancing sheets, so that it can Abandon the existing two brightening sheets from the backlight module, and replace them with the composite optical film provided by the present disclosure, so that the backlight module of the present disclosure not only has better optical performance, but also can meet the requirements of current products Extreme design and simple and extreme demand for assembly process.

5. Since the display device of the present disclosure also includes the above-mentioned composite optical film, the display device provided by the embodiment of the present disclosure can also use the first extension direction of the first triangular prism and the second extension direction of the second triangular prism The setting of the relationship of different directions can realize the selection of the display device with the best optical performance according to the actual needs of users, so that a variety of products with different positioning can be obtained, and thus users with different needs can be satisfied.

The above descriptions are only preferred embodiments of the present application, and are not intended to limit the present application. For those skilled in the art, there may be various modifications and changes in the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of this application shall be included within the protection scope of this application.

Claims

A composite optical film, wherein the composite optical film comprises from top to bottom:

a first lens layer, the first lens layer comprising a plurality of first triangular prisms arranged horizontally and parallel to each other;

a first substrate layer;

Adhesive layer;

The second lens layer, the first substrate layer and the second lens layer are bonded by the adhesive layer, and the second lens layer includes a plurality of second triangular prisms placed horizontally and parallel to each other, so The angle at the peak of the first triangular prism is greater than the angle at the peak of the second triangular prism;

a second substrate layer; and

back coating.
The composite optical film according to claim 1, wherein the adhesive layer has a thickness of 2 microns-5 microns and a refractive index of 1.49-1.56.
The composite optical film according to claim 1, wherein the bonding adhesive layer contains diffusion particles, and the doping ratio of the diffusion particles in the bonding adhesive layer is 1%-6%.
The composite optical film according to claim 3, wherein said back coating contains said diffusing particles, said diffusing particles comprising silicon dioxide, titanium dioxide, polymethyl methacrylate, n-butyl polymethacrylate ester.
The composite optical film according to claim 1, wherein the angle at the peak of the first triangular prism is 90°-100°, and the angle at the peak of the second triangular prism is 85°-90° °.
The composite optical film according to claim 1, wherein the distance between the peaks of two adjacent first triangular prisms is smaller than the distance between the peaks of two adjacent second triangular prisms;

The height of the first triangular prism is smaller than the height of the second triangular prism.
The composite optical film according to claim 1, wherein the included angle between the first extension direction of the first triangular prism on the horizontal plane and the second extension direction of the second triangular prism on the horizontal plane is at least Greater than 60°.
The composite optical film according to claim 1, wherein the composite optical film further comprises a first glue layer and a second glue layer, and the first lens layer is connected to the first glue layer through the first glue layer. The substrate layer is bonded, and the second lens layer is bonded to the second substrate layer through the second glue layer;

The refractive index of the first glue layer and/or the second glue layer is 1.53-1.56.
The composite optical film according to claim 8, wherein the glue used in the first glue layer, the second glue layer, and the bonding glue layer includes resin glue.
The composite optical film according to claim 1, wherein the haze of the back coating is 3%-25%.
A display device, including a backlight module, the backlight module includes a composite optical film; the composite optical film sequentially includes from top to bottom:

a first lens layer, the first lens layer comprising a plurality of first triangular prisms arranged horizontally and parallel to each other;

a first substrate layer;

Adhesive layer;

The second lens layer, the first substrate layer and the second lens layer are bonded by the adhesive layer, and the second lens layer includes a plurality of second triangular prisms placed horizontally and parallel to each other, so The angle at the peak of the first triangular prism is greater than the angle at the peak of the second triangular prism;

a second substrate layer; and

back coating.
The display device according to claim 11 , wherein the adhesive layer has a thickness of 2 microns-5 microns and a refractive index of 1.49-1.56.
The display device according to claim 11, wherein the bonding adhesive layer contains diffusion particles, and the doping ratio of the diffusion particles in the bonding adhesive layer is 1%-6%.
The display device according to claim 13, wherein the back coat contains the diffusion particles, and the diffusion particles include silicon dioxide, titanium dioxide, polymethyl methacrylate, poly-n-butyl methacrylate.
The display device according to claim 11, wherein the included angle at the apex of the first triangular prism is 90°-100°, and the included angle at the apex of the second triangular prism is 85°-90°.
The display device according to claim 11, wherein the distance between the peaks of two adjacent first triangular prisms is smaller than the distance between the peaks of two adjacent second triangular prisms;

The height of the first triangular prism is smaller than the height of the second triangular prism.
The display device according to claim 11, wherein the included angle between the first extension direction of the first triangular prism on the horizontal plane and the second extension direction of the second triangular prism on the horizontal plane is at least greater than 60° °.
The display device according to claim 11, wherein the composite optical film further comprises a first glue layer and a second glue layer, and the first lens layer is connected to the first substrate through the first glue layer Layer bonding, the second lens layer is bonded to the second substrate layer through the second glue layer;

The refractive index of the first glue layer and/or the second glue layer is 1.53-1.56.
The display device according to claim 18, wherein the glue used in the first glue layer, the second glue layer, and the bonding glue layer includes resin glue.
The display device according to claim 11, wherein the haze of the back coating is 3%-25%.