High-transmittance peep-proof film as well as preparation method and application thereof

Abstract

The invention provides a high-transmittance peep-proof film as well as a preparation method and application thereof, and belongs to the technical field of peep-proof films. The anti-peeping reflective film sequentially comprises a substrate layer, a light-transmitting layer, a reflective layer, an anti-peeping layer and an anti-reflection film layer from bottom to top, wherein the light-transmitting layer is composed of a first light-transmitting structure and a second light-transmitting structure; the peep-proof layer is composed of a first peep-proof structure and a second peep-proof structure; and a reflecting layer is arranged on the side wall of the periodic unit of the second light-transmitting structure. The high-transmittance peep-proof film and the preparation method thereof provided by the invention have a wide application prospect in the field of privacy protection of electronic equipment.

Description

Technical Field

[0001] The present invention relates to the technical field of privacy films, and in particular to a high-transmittance privacy film and a preparation method and application thereof. Background Art

[0002] In today's digital age, electronic devices have become an indispensable tool for people's lives and work. From daily mobile phones and tablets to office laptops and monitors, people process a lot of sensitive information on these devices, such as personal privacy and business secrets. Therefore, it has become an urgent need to effectively protect the screen content and prevent others from peeping from the side, and anti-peep films have emerged.

[0003] Early privacy film technology was relatively simple, mostly using dark films or shutter-like physical shielding structures. Although this type of privacy film can achieve the privacy function to a certain extent, it has many defects. Dark films will greatly reduce the transmittance of the screen, making the screen display dim. Even in a well-lit environment, it is difficult for users to see the screen content clearly. In a darker environment, the problem is more serious, seriously affecting the user experience. The shutter-type structure is prone to visual blind spots, and the control of light is not precise enough. A large amount of light is absorbed or blocked by the opaque area, resulting in a low overall transmittance, insufficient screen brightness, and gray-black color, which seriously affects the user's visual experience and comfort. Currently, privacy films on the market generally have the problem of unsatisfactory transmittance.

[0004] With the continuous advancement of science and technology, new privacy film technologies continue to emerge. For example, privacy films based on the principle of polarization achieve privacy protection by controlling the polarization direction of light, but this technology has high requirements for polarized materials, is expensive, and has large differences in privacy protection effects at different angles. There are also privacy films made using microstructure optical technology. Although they have improved the privacy protection performance and light transmittance to a certain extent, they still cannot balance the relationship between privacy protection and light transmittance in complex light environments, and it is difficult to meet the growing high-quality needs of users. For example, the privacy film proposed in patent number CN118550008A has improved the light transmittance to a certain extent by optimizing the design of the privacy layer and the anti-reflection and anti-glare layer, but the overall light transmittance improvement is limited; the privacy film of patent number CN203752629U increases the transmittance of light in the visible area, but still does not fundamentally solve the problem of low light transmittance of the privacy film. In addition, the preparation process of the privacy films proposed in patent numbers CN118859397A and CN221977143U is complex and costly, which is not conducive to large-scale production and promotion and application.

[0005] Therefore, studying a high-transmittance anti-peep film and a preparation method thereof has broad application prospects in the field of privacy protection of electronic devices. Summary of the invention

[0006] The purpose of the present invention is to solve the problem of low transmittance of current privacy film technology, and to provide a high-transmittance privacy film and a preparation method thereof.

[0007] The technical solution of the present invention is achieved in this way:

[0008] The present invention provides a high-transmittance privacy film, which comprises, from bottom to top, a base layer, a light-transmitting layer, a reflective layer, a privacy layer, and an anti-reflection film layer. The light-transmitting layer is composed of a first light-transmitting structure and a second light-transmitting structure; the privacy layer is composed of a first privacy layer and a second privacy layer; and a reflective layer is arranged on the side wall of a periodic unit of the second light-transmitting structure.

[0009] As a further improvement of the present invention, the substrate provides support for the entire anti-peep film and has a certain thickness. The appropriate material and thickness can be selected according to actual application requirements, generally between 0.1-0.5 mm.

[0010] As a further improvement of the present invention, the first light-transmitting structure is parallel to the substrate layer and is located above the substrate layer, with a thickness of 10-20 μm. The second light-transmitting structure is located above the first light-transmitting structure and is arranged periodically and is made of optical materials with high light transmittance, such as polyethylene terephthalate (PET).

[0011] As a further improvement of the present invention, the cross-section of the second light-transmitting structure is an isosceles trapezoid, with a height of 90-120 μm, an upper base width of 20-120 μm, and a lower base width of 30-130 μm.

[0012] As a further improvement of the present invention, the first privacy-prevention structure is filled in the periodic interval of the second light-transmitting structure. The second privacy-prevention structure is parallel to the structural layer composed of the second light-transmitting structure and the first privacy-prevention structure, and has a thickness of 1-3 μm. A material with light-shielding properties is used, such as black ink or light-shielding polymer.

[0013] As a further improvement of the present invention, the cross-section of the first privacy protection structure is an isosceles trapezoid, with a height of 90-120 μm, an upper base width of 5-10 μm, and a lower base width of 10-15 μm.

[0014] As a further improvement of the present invention, the reflective layer is made of metal material or dielectric material with high reflectivity, such as aluminum, silver or titanium dioxide, with a thickness of 1-2 μm, to increase the reflection of light and reduce the scattering and absorption of light in the second light-transmitting structure, thereby improving the light transmittance of the anti-peep film.

[0015] As a further improvement of the present invention, the thickness of the anti-reflection film layer is 1-5 μm, and by precisely controlling the thickness and refractive index of each structural single layer, the interference principle of light is used to reduce the reflection of light on the film surface and increase the transmittance of light. The thickness of each structural single layer is between tens of nanometers and hundreds of nanometers, and the refractive index is achieved by selecting different optical materials according to specific design requirements.

[0016] The present invention further protects a method for preparing a high-transmittance privacy film, which comprises the following steps:

[0017] S1. Preparation of base layer: Select appropriate materials, such as PET, and prepare a base layer with certain thickness and mechanical properties through processes such as casting and stretching;

[0018] S2, preparation of light-transmitting layer: using micro-nano processing techniques such as photolithography and etching to prepare a first light-transmitting structure and a second light-transmitting structure on the base layer;

[0019] S3, preparation of a reflective layer: depositing a reflective layer on both sides of the sidewalls of the periodic unit of the second light-transmitting structure by physical vapor deposition (PVD) or chemical vapor deposition (CVD) or other methods;

[0020] S4, preparation of anti-peeping layer: fill the periodic intervals of the second light-transmitting structure with a material having a light-shielding property by printing, coating or other processes to form a first anti-peeping structure. Then, prepare a second anti-peeping structure on the structural layer composed of the second light-transmitting structure and the first anti-peeping structure by spin coating, spray coating or other methods;

[0021] S5. Preparation of anti-reflection film layer: electron beam evaporation, magnetron sputtering and other methods are used to deposit structural single layers of different thicknesses and refractive indices in sequence according to design requirements to form an anti-reflection film layer.

[0022] The present invention has the following beneficial effects: The purpose of the present invention is to solve the problem of low transmittance of the current anti-peep film technology, and it provides a high-transmittance anti-peep film and its preparation method, including: a base layer, a light-transmitting layer, a reflective layer, an anti-peep layer, and an anti-reflective film layer. The base layer is located at the bottom; the light-transmitting layer is composed of a first light-transmitting structure and a second light-transmitting structure; the anti-peep layer is composed of a first anti-peep structure and a second anti-peep structure; the side wall of the periodic unit of the second light-transmitting structure is provided with a reflective layer; the top is an anti-reflective film layer. By arranging the reflective layer on both sides of the side wall of the periodic unit of the second light-transmitting structure, the scattering and absorption of light are reduced. At the same time, the anti-reflective film layer uses the interference principle of light to reduce the reflection of light on the surface of the film, so that the anti-peep film of the present invention has a higher transmittance. Compared with the existing anti-peep film, the transmittance can be increased by 20%-30%. The special design of the anti-peep layer effectively blocks the side light, ensuring that the screen content can only be seen when the screen is viewed from the front, protecting the privacy of the user. The preparation method of the present invention adopts common micro-nano processing and thin film deposition processes, which is easy to achieve large-scale production and reduces production costs.

[0023] The high-transmittance privacy film and the preparation method thereof provided by the present invention have broad application prospects in the field of privacy protection of electronic devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0025] Figure 1 It is a schematic diagram of the structure of a high-transmittance privacy film provided in some embodiments of the present invention.

[0026] Figure 2 It is a schematic diagram of the structure of a light-transmitting layer in a high-transmittance privacy film provided in some embodiments of the present invention.

[0027] Figure 3 It is a schematic diagram of the structure of an anti-peeping layer in a high-transmittance anti-peeping film provided in some embodiments of the present invention.

[0028] Figure 4 It is a flow chart of the preparation of a high-transmittance privacy film provided in some embodiments of the present invention.

[0029] Figure 5 It is the optical path simulation result of the high transmittance anti-peep film in Examples 1-4 of the present invention, wherein a is the optical path simulation result of the high transmittance anti-peep film prepared in Example 1, b is the optical path simulation result of the high transmittance anti-peep film prepared in Example 2, c is the optical path simulation result of the high transmittance anti-peep film prepared in Example 3, and d is the optical path simulation result of the high transmittance anti-peep film prepared in Example 4.

[0030] Description of reference numerals:

[0031] 10. Anti-peep film; 20. Base layer; 30. Light-transmitting layer; 40. Reflective layer; 50. Anti-peep layer; 60. Anti-reflection film layer; 31. First light-transmitting structure; 32. Second light-transmitting structure; 51. First anti-peep structure; 52. Second anti-peep structure. DETAILED DESCRIPTION

[0032] In order to more clearly and completely describe the technical solution of the present invention, the present invention is further described in detail through specific embodiments below. It should be understood that the specific embodiments described herein are only used to explain the present invention, and are not used to limit the present invention. Various changes can be made within the scope of the rights of the present invention.

[0033] In order to facilitate the understanding of the present invention, the present invention will be described more fully below with reference to the relevant drawings. The preferred embodiments of the present invention are given in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thoroughly understood.

[0034] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0035] Combine the following Figure 1-3 The invention discloses a high-transmittance privacy film and provides a method for preparing the high-transmittance privacy film.

[0036] See also Figure 1-Figure 3 The present invention discloses a high-transmittance privacy film, wherein the privacy film 10 comprises a base layer 20, a light-transmitting layer 30, a reflective layer 40, a privacy layer 50 and an anti-reflection film layer 60. The base layer 20 is located at the bottom; the light-transmitting layer 30 is composed of a first light-transmitting structure 31 and a second light-transmitting structure 32; the privacy layer 50 is composed of a first privacy structure 51 and a second privacy structure 52; a reflective layer 40 is provided on the periodic unit sidewall of the second light-transmitting structure 32; and an anti-reflection film layer 60 is provided at the top. By providing the reflective layer 40 on both sides of the periodic unit sidewall of the second light-transmitting structure 32, the scattering and absorption of light are reduced. At the same time, the anti-reflection film layer 60 reduces the reflection of light on the film surface by using the interference principle of light, so that the privacy film 10 of the present invention has a higher transmittance. Compared with the existing privacy film, the transmittance can be increased by 20%-30%. The special design of the privacy layer 50 effectively blocks the side light, ensuring that the screen content can only be seen when the screen is viewed from the front, thereby protecting the privacy of the user.

[0037] In the above embodiment, the base layer 20 provides support for the entire privacy film 10 and has a certain thickness. The appropriate material and thickness can be selected according to actual application requirements, which is generally between 0.1-0.5 mm.

[0038] The first light-transmitting structure 31 is parallel to the base layer 20 and is located above the base layer 20, with a thickness of 10-20 μm. The second light-transmitting structure 32 is located above the first light-transmitting structure 31 and is arranged periodically. It is made of an optical material with high light transmittance, such as polyethylene terephthalate (PET). The cross-section of the second light-transmitting structure 32 is an isosceles trapezoid, with a height of 90-120 μm, an upper base width of 20-120 μm, and a lower base width of 30-130 μm.

[0039] The first privacy-prevention structure 51 is filled in the periodic interval of the second light-transmitting structure 32. The second privacy-prevention structure 52 is parallel to the structure layer composed of the second light-transmitting structure 32 and the first privacy-prevention structure 51, and has a thickness of 1-3 μm. A material with light-shielding properties is used, such as black ink or light-shielding polymer.

[0040] The reflective layer 40 is made of a metal material or dielectric material with high reflectivity, such as aluminum, silver or titanium dioxide, with a thickness of 1-2 μm. It is used to increase the reflection of light and reduce the scattering and absorption of light in the second light-transmitting structure 32, thereby improving the light transmittance of the anti-peep film 10. The cross-section of the first anti-peep structure 51 is an isosceles trapezoid with a height of 90-120 μm, an upper base width of 5-10 μm, and a lower base width of 10-15 μm.

[0041] The thickness of the anti-reflection film layer 60 is 1-5 μm. The anti-reflection film 60 is composed of a plurality of structural monolayers with different thicknesses and different refractive indices. By precisely controlling the thickness and refractive index of each structural monolayer and utilizing the principle of light interference, the reflection of light on the film surface is reduced and the transmittance of light is increased. The thickness of each structural monolayer is between tens of nanometers and hundreds of nanometers, and the refractive index is achieved by selecting different optical materials according to specific design requirements.

[0042] like Figure 4 The present invention also provides a method for preparing a high-transmittance privacy film, the method comprising the following steps:

[0043] S1, preparation of base layer 20: selecting suitable materials, such as PET, PC, etc., and preparing a base layer with a certain thickness and mechanical properties through processes such as casting and stretching;

[0044] S2, preparation of the light-transmitting layer 30: using micro-nano processing techniques such as photolithography and etching to prepare a first light-transmitting structure 31 and a second light-transmitting structure 32 on the base layer 20;

[0045] S3, preparing the reflective layer 40: depositing the reflective layer 40 on both sides of the periodic unit sidewalls of the second light-transmitting structure 32 by physical vapor deposition (PVD) or chemical vapor deposition (CVD) or other methods;

[0046] S4, preparation of the anti-peeping layer 50: fill the periodic intervals of the second light-transmitting structure 32 with a material having a light-shielding property by printing, coating or other processes to form a first anti-peeping structure 51. Then, prepare a second anti-peeping structure 52 on the structural layer composed of the second light-transmitting structure 32 and the first anti-peeping structure 51 by spin coating, spray coating or other methods;

[0047] S5. Preparation of anti-reflection film layer 60: using methods such as electron beam evaporation and magnetron sputtering, sequentially depositing structural single layers with different thicknesses and refractive indices according to design requirements to form anti-reflection film layer 60.

[0048] Based on the description of the beneficial technical effects of the above-mentioned high-transmittance anti-peep film, its corresponding preparation method also has the same technical effects, which will not be repeated here.

[0049] Combine the following Figures 1 to 5 , the preparation method of the high-transmittance anti-peep film in the embodiment of the present invention is described in detail.

[0050] Example 1

[0051] A PET material with a thickness of 50 μm was selected, and a base layer 20 was prepared by a casting process. A first light-transmitting structure 31 with a thickness of 10 μm was prepared on the base layer 20 by using photolithography and etching techniques, and the material was PET. Then, a second light-transmitting structure 32 was prepared on the first light-transmitting structure, and the cross-section of each periodic unit of the second light-transmitting structure 32 was an isosceles trapezoid with a height of 90 μm, an upper bottom width of 30 μm, a lower bottom width of 36.3 μm, and an interval of 6.7 μm. The black ink was filled into the periodic interval of the second light-transmitting structure 32 by a printing process to form a first anti-peeping structure 51. A second anti-peeping structure 52 with a thickness of 2 μm was prepared on the structural layer composed of the second light-transmitting structure 32 and the first anti-peeping structure 51 by a spin coating process, and the material was a light-shielding polymer. Using electron evaporation technology, a silicon dioxide layer with a thickness of 50 nm and a refractive index of 1.45 and a tantalum pentoxide layer with a thickness of 80 nm and a refractive index of 1.65 were deposited in sequence to form an anti-reflection film layer 60. Reference Figure 5 a. The light path simulation of the anti-peep film prepared in this embodiment is performed using Rsoft software. From the light path simulation results, when the light propagates in the film, the light propagation path is relatively concentrated due to the narrow upper bottom of the second light-transmitting structure. In the absence of a reflective layer to enhance reflection, the light is scattered and absorbed relatively more, and the overall light transmission effect is relatively weak, which also shows that there are certain limitations in the control and utilization of light by simply relying on the light-transmitting structure, the anti-peeping layer, and the anti-reflection film layer.

[0052] Example 2

[0053] A PET material with a thickness of 50 μm was selected, and a base layer 20 was prepared by a casting process. A first light-transmitting structure 31 with a thickness of 10 μm was prepared on the base layer 20 by using photolithography and etching techniques, and the material was PET. Then, a second light-transmitting structure 32 was prepared on the first light-transmitting structure, and the cross-section of each periodic unit of the second light-transmitting structure 32 was an isosceles trapezoid with a height of 90 μm, an upper bottom width of 70 μm, a lower bottom width of 76.3 μm, and an interval of 6.7 μm. The black ink was filled into the periodic interval of the second light-transmitting structure 32 by a printing process to form a first anti-peeping structure 51. A second anti-peeping structure 52 with a thickness of 2 μm was prepared on the structural layer composed of the second light-transmitting structure 32 and the first anti-peeping structure 51 by a spin coating process, and the material was a light-shielding polymer. Using electron evaporation technology, a silicon dioxide layer with a thickness of 50 nm and a refractive index of 1.45 and a tantalum pentoxide layer with a thickness of 80 nm and a refractive index of 1.65 were deposited in sequence to form an anti-reflection film layer 60. Reference Figure 5 b. The light path of the privacy film prepared in this embodiment is simulated by Rsoft software. Figure 5 b In the corresponding embodiment 2, the width of the upper base of the second light-transmitting structure is changed to 70 μm, and no additional reflective layer material deposition process is used. Figure 5 Compared with a, the increase in the width of the upper base increases the space for light propagation and the distribution range of light is wider. Without the effect of the reflective layer, although the light propagation range changes, due to the lack of the reflective layer to enhance the reflection of light, the scattering and absorption of light still exist, and the overall light transmission effect is compared with Figure 5 There may be some improvement, but the extent will be limited.

[0054] Example 3

[0055] A PET material with a thickness of 50 μm was selected, and a base layer 20 was prepared by a casting process. A first light-transmitting structure 31 with a thickness of 10 μm was prepared on the base layer 20 using photolithography and etching techniques. The material was PET. Then, a second light-transmitting structure 32 was prepared on the first light-transmitting structure. The cross-section of each periodic unit of the second light-transmitting structure 32 was an isosceles trapezoid with a height of 90 μm, an upper base width of 70 μm, a lower base width of 76.3 μm, and an interval of 6.7 μm. An aluminum reflective layer 40 with a thickness of 1 μm was deposited on both sides of the sidewalls of the periodic unit of the second light-transmitting structure 32 by a magnetron sputtering method. Black ink was filled into the periodic intervals of the second light-transmitting structure 32 by a printing process to form a first anti-peeping structure 51. A second anti-peeping structure 52 with a thickness of 2 μm was prepared on top of the structural layer composed of the second light-transmitting structure 32 and the first anti-peeping structure 51 by a spin coating process. The material was a light-shielding polymer. Using electron evaporation technology, a silicon dioxide layer with a thickness of 50 nm and a refractive index of 1.45 and a tantalum pentoxide layer with a thickness of 80 nm and a refractive index of 1.65 are sequentially deposited to form an anti-reflection film layer 60. Figure 5 c, the light path simulation of the privacy film prepared in this embodiment is performed by Rsoft software. Figure 5 c, the width of the second light-transmitting structure on the bottom Figure 5 b is consistent with 70μm, but an aluminum reflective layer with a thickness of 1μm is deposited on both sides of the periodic unit sidewalls of the second light-transmitting structure by magnetron sputtering. The addition of the reflective layer greatly changes the propagation path of the light. The aluminum reflective layer increases the reflection of the light and reduces the scattering and absorption of the light in the second light-transmitting structure. From the simulation results, it can be seen that the propagation of light is more orderly, and the light intensity in the front direction is significantly enhanced. Figure 5 a and Figure 5 b. The light transmittance is significantly improved and the performance of the privacy film is optimized.

[0056] Example 4

[0057] A polycarbonate (PC) material with a thickness of 40 μm was selected, and a base layer 20 was prepared by an injection molding process. A first light-transmitting structure 31 with a thickness of 12 μm was prepared on the base layer 20 using photolithography and etching techniques, and the material was PC. Then, a second light-transmitting structure 32 was prepared on the first light-transmitting structure, and the cross-section of each periodic unit of the second light-transmitting structure 32 was an isosceles trapezoid with a height of 90 μm, an upper base width of 70 μm, a lower base width of 76.3 μm, and an interval of 6.7 μm. A silver reflective layer 40 with a thickness of 1.2 μm was deposited on both sides of the sidewalls of the periodic unit of the second light-transmitting structure 32 by a magnetron sputtering method. The light-shielding polymer was filled into the periodic interval of the second light-transmitting structure 32 by a coating process to form a first anti-peeping structure 51. A second anti-peeping structure 52 with a thickness of 2 μm was prepared on top of the structural layer composed of the second light-transmitting structure 32 and the first anti-peeping structure 51 by a spraying process, and the material was a mixture of black pigment and polymer. By using a magnetron sputtering method, a magnesium fluoride layer with a thickness of 60 nm and a refractive index of 1.48 and a titanium oxide layer with a thickness of 90 nm and a refractive index of 1.70 are sequentially deposited to form an anti-reflection film layer 60. Figure 5 d. The light path of the privacy film prepared in this embodiment is simulated by Rsoft software. Figure 5 d Corresponding to Example 4, the base layer material is PC, the thickness of the first light-transmitting structure is changed to 12 μm, the upper bottom width of the second light-transmitting structure is maintained at 70 μm, a silver reflective layer with a thickness of 1.2 μm is deposited by magnetron sputtering, and the material and thickness of the anti-reflection film layer are also changed. Figure 5 The light path simulation results of d are similar to those of Figure 5 c is similar, indicating that the high-transmittance privacy film and the preparation method thereof proposed in the present invention are universal and can effectively protect the privacy of screen contents.

[0058] The above is a detailed introduction to a high-transmittance privacy film and a preparation method thereof provided by the present invention. This article uses specific examples to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the core idea of ​​the present invention. It should be pointed out that for ordinary technicians in this technical field, without departing from the principles of the present invention, the present invention can also be improved and modified in a number of ways, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. A high-transmittance privacy film, characterized in that: From bottom to top, there are a base layer, a light-transmitting layer, a reflective layer, an anti-peeping layer, and an anti-reflection film layer. The light-transmitting layer is composed of a first light-transmitting structure and a second light-transmitting structure; the anti-peeping layer is composed of a first anti-peeping structure and a second anti-peeping structure; and a reflective layer is arranged on the side wall of the periodic unit of the second light-transmitting structure.

2. The high-transmittance privacy film according to claim 1, characterized in that: The thickness of the base layer is between 0.1-0.5 mm.

3. The high-transmittance privacy film according to claim 1, characterized in that: The first light-transmitting structure is parallel to the base layer and is located above the base layer, with a thickness of 10-20 μm. The second light-transmitting structure is located above the first light-transmitting structure and is arranged periodically. The first light-transmitting structure and the second light-transmitting structure are made of polyethylene terephthalate.

4. The high-transmittance privacy film according to claim 3, characterized in that: The cross section of the second light-transmitting structure is an isosceles trapezoid, with a height of 90-120 μm, an upper base width of 20-120 μm, and a lower base width of 30-130 μm.

5. The high-transmittance privacy film according to claim 1, characterized in that: The first anti-peeping structure is filled in the periodic intervals of the second light-transmitting structure. The second anti-peeping structure is parallel to the structural layer composed of the second light-transmitting structure and the first anti-peeping structure. The thickness is 1-3 μm and the structure is made of a material with light-shielding properties.

6. The high-transmittance privacy film according to claim 5, characterized in that: The cross section of the first anti-peeping structure is an isosceles trapezoid, with a height of 90-120 μm, an upper base width of 5-10 μm, and a lower base width of 10-15 μm.

7. The high-transmittance privacy film according to claim 1, characterized in that: The reflective layer is made of a metal material or a dielectric material with high reflectivity, and is selected from at least one of aluminum, silver or titanium dioxide, and has a thickness of 1-2 μm.

8. The high-transmittance privacy film according to claim 1, characterized in that: The thickness of the antireflection film layer is 1-5 μm.

9. A method for preparing a high-transmittance privacy film according to any one of claims 1 to 8, characterized in that: It includes the following steps: S1. Preparation of base layer: Select appropriate materials and prepare the base layer by at least one process of casting and stretching; S2, preparation of light-transmitting layer: using at least one micro-nano processing technology of photolithography and etching to prepare a first light-transmitting structure and a second light-transmitting structure on the base layer; S3, preparing a reflective layer: depositing a reflective layer on both sides of the sidewalls of the periodic unit of the second light-transmitting structure by at least one of physical vapor deposition and chemical vapor deposition; S4, preparation of an anti-peeping layer: filling a material having a light-shielding property into the periodic intervals of the second light-transmitting structure by at least one of printing and coating to form a first anti-peeping structure, and then preparing a second anti-peeping structure on the structural layer consisting of the second light-transmitting structure and the first anti-peeping structure by at least one of spin coating and spray coating; S5. Preparation of anti-reflection film layer: using at least one method of electron beam evaporation and magnetron sputtering, sequentially deposit structural single layers of different thicknesses and refractive indices according to design requirements to form an anti-reflection film layer.

10. Use of the high-transmittance privacy film according to any one of claims 1 to 8 in protective films for mobile phones, computers, and tablet computers.

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