An electromagnetic scattering film and an electronic device comprising the electromagnetic scattering film

Abstract

The application discloses an electromagnetic scattering film and an electronic device comprising the electromagnetic scattering film, wherein the electromagnetic scattering film comprises a metal layer; a through hole penetrating through upper and lower surfaces of the metal layer is arranged on the metal layer, and the maximum value of the distance s between any two points on the profile of the cross section of the through hole is less than the wavelength λ of the microwave incident into the through hole, so that the microwave is diffracted after being incident into the through hole. By arranging the through hole with the wavelength less than the wavelength of the microwave on the metal layer, the originally linearly transmitted microwave is diffracted after being incident into the through hole, and the spatial range of microwave emission and / or reception is increased.

Description

[0001] The present application claims priority to two Chinese patent applications, 1. Application No. 201920847012.6, filed on June 5, 2019, and 2. Application No. 201910489146.X, filed on June 5, 2019, the contents of which are incorporated herein by reference in their entirety. TECHNICAL FIELD

[0002] The present application relates to the technical field of communication, in particular to an electromagnetic scattering film and an electronic device comprising the electromagnetic scattering film. BACKGROUND

[0003] Microwave communication is a communication using electromagnetic waves with a wavelength between 0.1 millimeter and 1 meter. The frequency range corresponding to this wavelength range is 300 MHz (0.3 GHz) - 3 THz. Microwave communication has directionality due to the straight-line transmission characteristics of microwaves, and when a user is not in the specified direction area, the signal cannot be received, resulting in a communication blind area. SUMMARY

[0004] An object of the present application is to provide an electromagnetic scattering film, through which microwaves can be diffracted after passing through the through hole, thereby increasing the spatial range of microwave transmission and / or reception and avoiding communication blind areas as much as possible.

[0005] Another object of the present application is to provide an electronic device with a large microwave signal transmission and / or reception range, providing a good user experience.

[0006] To achieve the above object, the following technical solutions are provided:

[0007] In one aspect, an electromagnetic scattering film is provided, comprising a metal layer, wherein the metal layer is provided with a through hole penetrating through its upper and lower surfaces, and the maximum value of the distance s between any two points on the profile of the cross section of the through hole is less than the wavelength λ of the microwave incident into the through hole, so that the microwave is diffracted after being incident into the through hole. By providing a through hole smaller than the wavelength of the microwave on the metal layer, the originally straight-line transmitted microwave is diffracted after being incident into the through hole, thereby increasing the spatial range of microwave transmission and / or reception.

[0008] In another aspect, an electronic device is provided, comprising the electromagnetic scattering film and a circuit device, wherein the circuit device comprises a signal circuit, and the electromagnetic scattering film is connected to the circuit device.

[0009] The electronic device provided by the embodiment of the present application is connected with the electromagnetic scattering film, and the microwave signal transmitted and / or received by the signal circuit can be diffracted through the through hole of the electromagnetic scattering film, so that the spatial range of the microwave signal transmission and / or reception of the electronic device is expanded, the signal blind area problem of the electronic device is avoided, and the user experience is improved. BRIEF DESCRIPTION OF DRAWINGS

[0010] Figure 1 The structural schematic diagram of the electromagnetic scattering film provided by the embodiment of the present application is shown in the figure;

[0011] Figure 2 The structural schematic diagram of the through hole of the electromagnetic scattering film of the embodiment of the present application is shown in the figure;

[0012] Figure 3 The cross-sectional schematic diagram of the electromagnetic scattering film with a circular hole in the embodiment of the present application is shown in the figure (A-A direction); Figure 1

[0013] Figure 4 The cross-sectional schematic diagram of the electromagnetic scattering film with a square hole in the embodiment of the present application is shown in the figure;

[0014] Figure 5 The cross-sectional schematic diagram of the electromagnetic scattering film with a combined hole type in the embodiment of the present application is shown in the figure;

[0015] Figure 6 The structural schematic diagram of the metal layer of the electromagnetic scattering film in the embodiment of the present application is shown in the figure;

[0016] Figure 7 The structural schematic diagram of the metal layer of the electromagnetic scattering film in another embodiment of the present application is shown in the figure;

[0017] Figure 8 The structural schematic diagram of the electromagnetic scattering film provided by the embodiment of the present application is shown in the figure;

[0018] Figure 9 The structural schematic diagram of the electromagnetic scattering film provided by another embodiment of the present application is shown in the figure;

[0019] Figure 10 The structural schematic diagram of the electromagnetic scattering film in the embodiment of the present application (the non-flat surface of the metal layer away from the insulating layer) is shown in the figure;

[0020] Figure 11 The structural schematic diagram of the electromagnetic scattering film in the embodiment of the present application (both the upper and lower surfaces of the metal layer are non-flat surfaces) is shown in the figure;

[0021] Figure 12 The structural schematic diagram of the electronic device provided by the embodiment of the present application is shown in the figure.

[0022] REFERENCE NUMERALS:

[0023] ​1, metal layer; 11, through hole; 111, cross section; 1111, point; 2, insulating layer; 3, conductive bump; 4, adhesive film layer; 5, bump part; 100, electromagnetic scattering film; 200, circuit device; 201, signal circuit. DETAILED DESCRIPTION

[0024] To make the technical problems solved by the present application, the technical solutions adopted and the technical effects achieved more clear, the technical solutions of the embodiments of the present application will be further described in detail below with reference to the drawings. Obviously, the described embodiments are only a part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0025] Figure 1 is a structural schematic diagram of the electromagnetic scattering film of the embodiment of the present application. As shown in Figure 1 , the electromagnetic scattering film of the preferred embodiment of the present application includes a metal layer 1, the metal layer 1 is provided with a through hole 11 penetrating through its upper and lower surfaces, the maximum value of the distance s between any two points on the profile of the cross section of the through hole 11 is less than the wavelength λ of the microwave incident into the through hole 11, so that the microwave incident into the through hole 11 will diffract. In the field of communication technology, an important means to realize data exchange is the transmission of signals, and the transmission of microwave signals belongs to one of the means. Since the microwave signal is linearly transmitted in a specified direction, the area not in the specified direction may not receive the microwave signal, or the microwave signal cannot be transmitted to the area outside the specified direction, resulting in communication failure. Figure 1 The arrow direction shown in the figure is an exemplary microwave transmission direction, the scattering film provided by the embodiment of the present application adopts the principle of diffraction, by setting the through hole 11 on the metal layer 1 which is much smaller than the wavelength of the microwave, when the microwave is transmitted through the through hole 11, diffraction will occur, so that the original directional transmission path of the microwave is changed, and multiple directional transmission paths are generated through diffraction, expanding the spatial range of microwave transmission and / or reception. Among them, the cross section referred to by the present application refers to the cross section of the through hole 11 obtained by cutting the scattering film along the A-A direction shown in the figure. Figure 1

[0026] Figures 3-5 is a cross-sectional schematic diagram of the electromagnetic scattering film of the embodiment of the present application. The through hole 11 of the embodiment of the present application can be one or a combination of two or more of a circular hole or a non-circular hole, for example, the through hole 11 can be a polygonal hole such as a triangular hole, a quadrilateral hole, etc. or other irregularly shaped hole, as long as it can make the microwave incident into the through hole 11 to diffract.

[0027] In the embodiment of the present application, there are multiple points on the profile of the cross section of the through hole 11, and the straight line distance between any two points. Specifically, as shown in​Figure 2 As shown in the drawings, taking a circular hole as an example, along the central axis direction of the through hole 11, the through hole 11 has a plurality of mutually parallel cross sections 111, and each cross section profile has a plurality of mutually spaced points 1111, and the distance between two points 1111 is a straight line. The present application limits the maximum distance s between any two points on the profile of the cross section of the through hole 11 to be less than the wavelength λ of the microwave incident into the through hole 11, so as to limit the size of the through hole 11 to be less than the wavelength λ of the microwave incident into the through hole 11, and to ensure that the microwave incident into the through hole 11 can diffract. As shown in the drawings, that is, the A-A view in the drawings, when the through hole 11 is a circular hole, the maximum distance s between any two points on the profile of the cross section of the through hole 11 is the diameter of the through hole 11. Figure 3 As shown in the drawings, that is, the A-A view in the drawings, when the through hole 11 is a circular hole, the maximum distance s between any two points on the profile of the cross section of the through hole 11 is the diameter of the through hole 11. Figure 3 As shown in the drawings, that is, the A-A view in the drawings, when the through hole 11 is a circular hole, the maximum distance s between any two points on the profile of the cross section of the through hole 11 is the diameter of the through hole 11. Figure 4 As shown in the drawings, that is, the A-A view in the drawings, when the through hole 11 is a circular hole, the maximum distance s between any two points on the profile of the cross section of the through hole 11 is the diameter of the through hole 11. Figure 4 As shown in the drawings, that is, the A-A view in the drawings, when the through hole 11 is a circular hole, the maximum distance s between any two points on the profile of the cross section of the through hole 11 is the diameter of the through hole 11. Figure 5 As shown in the drawings, that is, the A-A view in the drawings, when the through hole 11 is a circular hole, the maximum distance s between any two points on the profile of the cross section of the through hole 11 is the diameter of the through hole 11. Figure 5 As shown in the drawings, that is, the A-A view in the drawings, when the through hole 11 is a circular hole, the maximum distance s between any two points on the profile of the cross section of the through hole 11 is the diameter of the through hole 11.

[0028] In a preferred embodiment, the distance s between any two points on the profile of the cross section of the through hole 11 is 1 μm to 500 μm, and the distance s is less than the wavelength λ of the microwave. It should be noted that the microwave in this embodiment carries a signal for microwave communication according to actual use requirements. The wavelength λ of the microwave in this embodiment is 0.1 mm to 1 m. From the above distance s and wavelength λ, the size of the through hole 11 is much smaller than the wavelength of the microwave, so that the microwave can diffract after entering the through hole 11.

[0029] Preferably, the ratio of the distance s between any two points on the cross-sectional profile of the through hole 11 to the wavelength λ of the microwave is 1:200-1:100. By defining the size relationship between the distance s between two points on the cross-sectional profile of the through hole 11 and the wavelength λ of the microwave, it is ensured that the distance s between any two points on the cross-sectional profile of the through hole 11 is much smaller than the wavelength λ of the microwave, which ensures that diffraction occurs no matter from which direction the microwave is incident, thereby ensuring that the microwave is converted from directional transmission to multi-directional divergent transmission, and further ensuring that the user can receive signals in different directions.

[0030] In addition, in the embodiment of the present application, the number of the through holes 11 arranged on the metal layer 1 per 1 cm 2 is 1000 or more. By arranging as many through holes 11 as possible, the effective contact area of the microwave with the electromagnetic scattering film can be increased, so that as many microwaves as possible are scattered. Preferably, the opening rate of the metal layer 1 is 1%-99%. The opening rate of the metal layer 1 is the ratio of the total area of the openings (the sum of the areas of all the openings) on the metal layer 1 to the main area of the metal layer 1, which is 1%-99%. Specifically, taking any one surface of the metal layer 1 as an example, the opening rate refers to the ratio of the sum of the areas of all the openings arranged on the surface to the surface area of the metal layer 1. Through the design, the opening area on the metal layer 1 is controlled, avoiding the problem that the metal layer 1 is easily broken due to too large opening area, or the problem that a large number of microwaves are directly emitted by the metal layer 1 without diffraction through the through holes 11 due to too small opening area.

[0031] In the embodiment of the present application, the plurality of through holes 11 are regularly or irregularly distributed on the metal layer 1; and / or, the shapes of the plurality of through holes 11 are the same or different; and / or, the sizes of the plurality of through holes 11 are the same or different. Wherein, the regular distribution of the through holes 11 on the metal layer 1 means that each through hole 11 is uniformly distributed on the metal layer 1; and the irregular distribution of the through holes 11 on the metal layer 1 means that each through hole 11 is distributed disorderly on the metal layer 1.

[0032] In the embodiment of the present application, the thickness t of the metal layer 1 is 0.1-10 μm, which is designed to ensure that the metal layer 1 is not easily broken and has good flexibility. Preferably, the metal layer 1 is made of any one or more of copper, aluminum, titanium, zinc, iron, nickel, chromium, cobalt, silver and gold.

[0033] In the embodiment, the two surfaces of the metal layer 1 can be flat surfaces or non-flat surfaces. The non-flat surfaces include regular non-flat surfaces and irregular non-flat surfaces. When the surface of the metal layer 1 is a regular non-flat surface, the regular non-flat surface is a structure with periodic undulations, and the undulations have the same amplitude and interval. When the surface of the metal layer 1 is an irregular non-flat surface, the irregular non-flat surface is a structure with non-periodic undulations, and the undulations have different amplitudes and / or intervals. For example, Figure 1 In the example, the two surfaces of the metal layer 1 are flat surfaces. For example, Figure 6 In the example, one surface of the metal layer 1 is a flat surface, and the other surface is an irregular non-flat surface. For example, Figure 7 In the example, the two surfaces of the metal layer 1 are irregular non-flat surfaces.

[0034] Figure 8 is a structural schematic diagram of the electromagnetic scattering film according to the embodiment of the present application. As shown in Figure 8 , one surface of the metal layer 1 is provided with an insulating layer 2. The insulating layer 2 is provided to insulate the metal layer 1 and prevent short circuit with the surrounding circuit. The insulating layer 2 can be an insulating layer film provided on the surface of the metal layer 1 or an insulating coating layer coated on the surface of the metal layer 1. In the embodiment of the present application, the insulating layer 2 has the functions of insulation and protection, and ensures that the metal layer 1 is not scratched or damaged during use. Preferably, the thickness of the insulating layer 2 is 1 μm to 25 μm, and the insulating layer 2 includes any one of a PPS film layer, a PEN film layer, a polyester film layer, a polyimide film layer, a film layer formed after curing of epoxy resin ink, a film layer formed after curing of polyurethane ink, a film layer formed after curing of modified acrylic resin, or a film layer formed after curing of polyimide resin.

[0035] Referring to Figure 9 , in order to improve the connection stability between the insulating layer 2 and the metal layer 1 and prevent peeling and falling off between the insulating layer 2 and the metal layer 1, the metal layer 1 in the embodiment is provided with a plurality of protruding portions 5 on the side close to the insulating layer 2, and the protruding portions 5 protrude into the insulating layer 2. In addition, the protruding portions 5 can protrude from the metal layer 1 toward the insulating layer 2 or protrude from the insulating layer 2 toward the metal layer 1, as long as they are beneficial to improving the connection stability between the insulating layer 2 and the metal layer 1. It should be noted that, Figure 9The shape of the protrusions 5 in the drawings is only exemplary. Due to differences in process means and parameters, the shape of each protrusion 5 can be regular or irregular solid geometry, such as one or more of sharp corner shape, inverted cone shape, granular shape, branch shape, column shape, and block shape. The protrusions 5 in the embodiments of the present application are not limited to the shapes shown in the drawings and described above, and any protrusion 5 that is beneficial to improving the connection stability between the insulating layer 2 and the metal layer 1 is within the scope of the present application. The shapes of the plurality of protrusions 5 can be the same or different, and the sizes of the protrusions 5 can also be the same or different, that is, the shapes of the plurality of protrusions 5 can be one or more of sharp corner shape, inverted cone shape, granular shape, branch shape, column shape, and block shape, and the sizes of the plurality of protrusions 5 of the same shape can not be exactly the same. In addition, the plurality of protrusions 5 are continuously or discontinuously distributed on the side of the metal layer 1 close to the insulating layer 2, for example, when the plurality of protrusions 5 are continuously distributed in sharp corner shape, a regular, periodic, tooth-like three-dimensional pattern or an irregular, disordered, tooth-like three-dimensional pattern can be formed. Of course, only one of the above is listed here, and combinations of other shapes described above are also within the scope of the present application, and will not be listed one by one here. In other embodiments of the present application, the surface of the metal layer 1 is a non-flat surface, which is also beneficial to the connection stability and reliability of the metal layer 1 and the insulating layer 2.

[0036] In the embodiments of the present application, the protrusions 5 can be conductive or non-conductive. Preferably, the protrusions 5 include one or more of metal particles, carbon nanotube particles, ferrite particles, insulator particles, and coated composite particles (conductor particles formed by a conductor layer as a coating layer, or another insulator particle coated with an insulator, etc.). When the protrusions 5 are conductive, the protrusions 5 include one or more of metal particles, carbon nanotube particles, ferrite particles, and coated composite particles (conductor particles formed by a conductor layer as a coating layer). When the protrusions 5 are non-conductive, the protrusions 5 include one or more of insulator particles and coated composite particles (another insulator particle coated with an insulator, etc.). In addition, when the protrusions 5 are metal particles, the protrusions 5 include single metal particles and / or alloy particles. The single metal particles are made of any one of copper, aluminum, titanium, zinc, iron, nickel, chromium, cobalt, silver, and gold, and the alloy particles are made of any two or more of copper, aluminum, titanium, zinc, iron, nickel, chromium, cobalt, silver, and gold. It should be noted that the plurality of protrusions 5 can be the same as or different from the material of the metal layer 1.

[0037] In addition, in the process of implementation, when the protrusions 5 are conductive, the metal layer 1 can be formed first, then the protrusions 5 are formed on the metal layer 1 by other processes, and finally the insulating layer 2 is formed on the side of the metal layer 1 where the protrusions 5 are formed. Of course, the metal layer 1 and the protrusions 5 can also be integrally formed. The height of the protrusions 5 is preferably 0.1 μm to 15 μm. When the protrusions 5 have conductive properties, the height of the protrusions 5 is less than the thickness of the insulating layer 2 to prevent the insulating layer 2 from failing.

[0038] As Figure 8 In the example of FIG. 1, the surface of the metal layer 1 is provided with conductive protrusions 3 to facilitate the discharge of interference charges accumulated in the metal layer 1 when the electromagnetic scattering film is used, thereby avoiding the accumulation of interference charges to form interference sources. A plurality of conductive protrusions 3 are arranged on the side of the metal layer 1 away from the insulating layer 2. Figure 8 In the example of FIG. 2, the metal layer 1 is formed first, and then the conductive protrusions 3 are formed on the metal layer 1 by other processes. Figure 9 In the example of FIG. 3, the metal layer 1 and the conductive protrusions 3 are integrally formed. It should be noted that the shape of the conductive protrusions 3 in the figure is only exemplary, and due to differences in process means and parameters, the shape of each conductive protrusion 3 can be regular or irregular three-dimensional geometry, for example, the shape of the plurality of conductive protrusions 3 can be one or more of sharp, inverted cone, granular, dendritic, columnar, and blocky.

[0039] In addition, for the plurality of conductive protrusions 3 arranged on the side of the metal layer 1 away from the insulating layer 2, the shape of each conductive protrusion 3 can be the same or different, and the size of each conductive protrusion 3 can also be the same or different, that is, the shape of the plurality of conductive protrusions 3 can be one or more of sharp, inverted cone, granular, dendritic, columnar, and blocky, and the size of the plurality of conductive protrusions 3 of the same shape can not be exactly the same. In addition, the plurality of conductive protrusions 3 are continuously or discontinuously distributed on the side of the metal layer 1 away from the insulating layer 2, for example, when the plurality of conductive protrusions 3 are sharp and continuously distributed, a regular, periodic, tooth-like three-dimensional pattern can be formed, or an irregular, disordered, tooth-like three-dimensional pattern can be formed. Of course, only one of these cases is listed here, and other combinations of the above are also within the scope of the present application, and will not be listed one by one here.

[0040] In the embodiment of the present application, the conductive protrusions 3 comprise one or more of metal particles, carbon nanotube particles and ferrite particles, the conductive protrusions 3 comprise single metal particles and / or alloy particles; wherein the single metal particles are made of any one of copper, aluminum, titanium, zinc, iron, nickel, chromium, cobalt, silver and gold, and the alloy particles are made of any two or more of copper, aluminum, titanium, zinc, iron, nickel, chromium, cobalt, silver and gold. It should be noted that the conductive protrusions 3 can be the same as the material of the metal layer 1 or can not be the same.

[0041] In the embodiment of the present application, the height h of the conductive protrusions 3 is 0.1-30 μm to make the product as light and thin as possible under the premise of meeting the grounding effect.

[0042] As shown in Figure 9 In order to facilitate the use of the electromagnetic scattering film, the metal layer 1 in the embodiment is provided with an adhesive film layer 4 on the side away from the insulating layer 2, and a plurality of conductive protrusions 3 extend into the adhesive film layer 4. The conductive protrusions 3 can be at a certain distance from the outer surface of the adhesive film layer 4, or can be in contact with the outer surface of the adhesive film layer 4 or extend out of the outer surface of the adhesive film layer 4; the outer surface of the adhesive film layer 4 can be a flat surface without undulations, or can be a non-flat surface with gentle undulations. In use, the plurality of conductive protrusions 3 pierce the adhesive film layer 4 and ground to lead out the interference charges accumulated in the metal layer 1. In other embodiments of the present application, the surface of the metal layer 1 is a non-flat surface, so that an uneven concave-convex surface can be formed on the surface of the metal layer 1. This design can make more adhesive amount connect with the metal layer 1, thereby improving the connection stability and reliability of the metal layer 1 and the adhesive film layer 4.

[0043] Preferably, the material of the adhesive film layer 4 is selected from any one of modified epoxy resin, acrylic, modified rubber, modified thermoplastic polyimide, polyurethane, polyacrylate and silicone.

[0044] In the embodiment of the present application, the height of the conductive protrusions 3 is preferably 0.1 μm-30 μm, and the thickness of the adhesive film layer 4 is preferably 0.1 μm-45 μm. By setting the height of the conductive protrusions 3 to be preferably 0.1 μm-30 μm and the thickness of the adhesive film layer 4 to be preferably 0.1 μm-45 μm, it is ensured that the conductive protrusions 3 can pierce the adhesive film layer 4 when the electromagnetic scattering film is used, thereby ensuring that the electromagnetic scattering film can be grounded.

[0045] As shown in Figures 10-11 In the embodiment of the present application, the height of the conductive protrusions 3 is preferably 0.1 μm-30 μm, and the thickness of the adhesive film layer 4 is preferably 0.1 μm-45 μm. By setting the height of the conductive protrusions 3 to be preferably 0.1 μm-30 μm and the thickness of the adhesive film layer 4 to be preferably 0.1 μm-45 μm, it is ensured that the conductive protrusions 3 can pierce the adhesive film layer 4 when the electromagnetic scattering film is used, thereby ensuring that the electromagnetic scattering film can be grounded. Figure 10One surface of the metal layer 1 in the electromagnetic scattering film shown is a flat surface, and the other surface is an irregular non-flat surface. One surface of the adhesive film layer 4 connected with the metal layer 1 also presents an irregular non-flat surface. Figure 11 Both surfaces of the metal layer 1 in the electromagnetic scattering film shown are irregular non-flat surfaces. The surfaces of the insulating layer 2 and the adhesive film layer 4 connected with the metal layer 1 also present irregular non-flat surfaces. Through the design, the surface of the metal layer 1 is irregular and non-flat, which can improve the connection stability and reliability of the insulating layer 2 and the adhesive film layer 4.

[0046] In order to adapt to more application scenarios, the electromagnetic scattering film described in the application is a flexible foldable and bendable structure. Specifically, by using a flexible structure such as a metal circuit board or an FPC circuit board for the metal layer 1, the adhesive film layer 4 provided on one surface of the metal layer 1 for connection has foldability, and the insulating layer 2 provided on the other surface of the metal layer 1 for protection also has foldability, so that the electromagnetic scattering film of the application has foldable and bendable performance. In actual use, the scattering film can be bent or folded into any shape such as an arc structure, an elliptical structure, a stacked structure, or a semi-closed structure according to needs.

[0047] Figure 12 is a structural schematic diagram of an electronic device provided by an embodiment of the application. As shown in Figure 12 The electronic device includes an electromagnetic scattering film 100 and a circuit device 200, the circuit device 200 includes a signal circuit 201, and the electromagnetic scattering film 100 is connected with the circuit device 200. In this embodiment, the circuit device 200 is connected with the adhesive film layer 4 of the electromagnetic scattering film 100. In other examples, the circuit device 200 itself can have an adhesive layer, and the electromagnetic scattering film does not have an adhesive film layer 4, and the purpose of the application can also be achieved.

[0048] In summary, the electronic device provided by the embodiment of the application is connected with the circuit device, and the microwave signals transmitted and / or received through the signal circuit can be diffracted through the through hole 11 of the electromagnetic scattering film, which expands the spatial range of the microwave signal transmission and / or reception of the electronic device, avoids the signal blind area problem of the electronic device, and improves the user experience.

[0049] Note that the above merely describes preferred embodiments of the present application and the principles of the technology applied. Those skilled in the art will understand that the present application is not limited to the specific embodiments described herein, and that various obvious changes, modifications and substitutions can be made without departing from the scope of the present application. Therefore, although the present application has been described in detail through the above embodiments, the present application is not limited to the above embodiments, and can include more other equivalent embodiments without departing from the concept of the present application, and the scope of the present application is determined by the scope of the claims.

Claims

1. An electromagnetic scattering film, characterized in that, The device includes a metal layer with through holes penetrating its upper and lower surfaces. The maximum value of the distance s between any two points on the profile of the cross-section of the through hole is less than the wavelength λ of the microwave entering the through hole, and the ratio of the distance s between any two points on the profile of the cross-section of the through hole to the wavelength λ of the microwave is 1:200 to 1:

100. The thickness t of the metal layer is 0.1 μm to 10 μm, so that the microwave diffracts after entering the through hole. Diffraction is used to generate transmission paths in multiple directions, expanding the spatial range of microwave transmission and / or reception; An insulating layer is provided on one side of the metal layer, and the thickness of the insulating layer is 1μm to 25μm; a plurality of protrusions are provided on the side of the metal layer near the insulating layer, and the protrusions extend into the insulating layer; the height of the protrusions is 0.1μm to 15μm; the shape of the plurality of protrusions is one or more of the following: pointed, inverted conical, granular, dendritic, columnar, and blocky.

2. The electromagnetic scattering film as described in claim 1, characterized in that, The distance s between any two points on the cross-sectional profile of the through hole is 1μm to 500μm, and is less than the wavelength λ of the microwave.

3. The electromagnetic scattering film as described in claim 1, characterized in that, per 1cm 2 The number of through holes provided on the metal layer is more than 1000.

4. The electromagnetic scattering film as described in claim 3, characterized in that, The porosity of the metal layer is 1% to 99%.

5. The electromagnetic scattering film according to any one of claims 1-4, characterized in that, The insulating layer is an insulating film layer disposed on the surface of the metal layer or an insulating coating layer coated on the surface of the metal layer.

6. The electromagnetic scattering film according to any one of claims 1-4, characterized in that, The surface of the metal layer is provided with conductive protrusions.

7. The electromagnetic scattering film as described in claim 6, characterized in that, The height h of the conductive protrusion is 0.1μm~30μm.

8. The electromagnetic scattering film as described in claim 7, characterized in that, An adhesive film layer is disposed on the surface of the metal layer that is on the same side as the conductive protrusion, and the conductive protrusion extends into the adhesive film layer.

9. The electromagnetic scattering film as described in claim 6, characterized in that, The shape of the conductive protrusion is one or more combinations of the following: pointed, inverted conical, granular, dendritic, columnar, and blocky.

10. The electromagnetic scattering film according to any one of claims 1-4, characterized in that, The surface of the metal layer is not flat.

11. The electromagnetic scattering film according to any one of claims 1-4, characterized in that, The electromagnetic scattering film has a flexible structure.

12. An electronic device comprising an electromagnetic scattering film as described in any one of claims 1-11, further comprising a circuit device including a signal circuit, wherein the electromagnetic scattering film is connected to the circuit device.

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