CN112886265A

CN112886265A - Scattering film and electronic equipment

Info

Publication number: CN112886265A
Application number: CN201911199864.XA
Authority: CN
Inventors: 苏陟; 高强
Original assignee: Guangzhou Fangbang Electronics Co Ltd
Current assignee: Guangzhou Fangbang Electronics Co Ltd
Priority date: 2019-11-29
Filing date: 2019-11-29
Publication date: 2021-06-01

Abstract

The invention discloses a scattering film and electronic equipment, wherein the scattering film comprises a scattering layer, an impedance gradual change layer and a protective layer which are sequentially stacked along the stacking direction, and the scattering layer is provided with a scattering structure through which electromagnetic waves can pass, so that the electromagnetic waves are dispersed to the periphery after passing through the scattering structure, the space range of electromagnetic wave emission is enlarged, the function of dispersing the electromagnetic waves is realized, and communication blind areas are avoided as far as possible. By arranging the impedance gradual change layer between the scattering layer and the protective layer, the impedance of the impedance gradual change layer along the stacking direction is gradually changed from the impedance of the scattering structure to the impedance of the protective layer, so that the impedance sudden change of the interface of the scattering structure and the protective layer is eliminated, the energy loss of electromagnetic waves in the process of passing through the scattering film is reduced, and the signal transmission distance and the quality of transmission signals are improved.

Description

Scattering film and electronic equipment

Technical Field

The invention relates to the technical field of communication equipment, in particular to a scattering film and electronic equipment.

Background

Electromagnetic wave communication is communication using electromagnetic waves having a wavelength between 0.1 mm and 1 m. The frequency range corresponding to the electromagnetic wave of the wavelength band is 300MHz (0.3GHz) -3 THz. Unlike the transmission mode of modern communication networks such as coaxial cable communication, optical fiber communication, satellite communication, etc., electromagnetic wave communication is communication directly using electromagnetic waves as a medium, does not require a solid medium, and can use electromagnetic wave transmission when there is no obstacle in a straight-line distance between a transmitting end and a receiving end.

In the transmission process of electromagnetic waves, the loss of energy directly affects the distance of signal propagation and the quality of the transmitted signal. When electromagnetic waves pass through the same medium, energy is basically not lost; when the electromagnetic wave passes through the interface surfaces of different media, a partial reflection phenomenon occurs. Due to the reflection of part of the electromagnetic wave, the electromagnetic energy in the propagation direction is lost, which seriously affects the distance of signal propagation and the quality of the transmitted signal.

Disclosure of Invention

One object of an embodiment of the present invention is to: the scattering film is provided, on one hand, the space range of electromagnetic wave emission can be enlarged, and communication blind areas can be avoided as much as possible; on the other hand, the energy loss of the electromagnetic wave in the process of passing through the scattering film can be reduced, and the signal propagation distance and the quality of the transmission signal can be improved.

Another object of an embodiment of the present invention is to: an electronic device is provided which has a large spatial range of electromagnetic wave emission, a long signal propagation distance, and a signal quality number.

In a first aspect, an embodiment of the present invention provides a scattering film, including a scattering layer, an impedance-graded layer, and a protective layer, which are sequentially stacked along a stacking direction;

the scattering layer is provided with a scattering structure through which electromagnetic waves can pass, so that the electromagnetic waves are diffused to the periphery after passing through the scattering structure;

the impedance of the scattering structure is a first impedance value, the impedance of the protective layer is a second impedance value, and the impedance of the impedance gradual change layer along the stacking direction gradually changes from the first impedance value to the second impedance value.

Optionally, the impedance gradient layer includes n sublayers, which are respectively a first sublayer to an nth sublayer stacked in sequence along the stacking direction, the impedance of the first sublayer in contact with the scattering layer is a first impedance value, the impedance of the nth sublayer in contact with the protective layer is a second impedance value, and the impedances of the first sublayer to the nth sublayer are gradually changed along the stacking direction, where n is greater than or equal to 3.

Optionally, each of the sub-layers is made of a different substrate, and the impedance of each of the substrates is graded along the stacking direction.

Optionally, each sublayer is made of the same base material, each sublayer is provided with a plurality of first through holes penetrating through the sublayer, the first through holes on the same sublayer have the same volume, and the first through holes on different sublayers have different volumes and/or different numbers, so that the impedances of the first sublayer to the nth sublayer gradually change along the stacking direction.

Optionally, the volumes of the first through holes on each sub-layer are the same, and the number of the first through holes on different sub-layers decreases sequentially along the stacking direction.

Optionally, the number of the first through holes formed in each sublayer is equal, the volume of each first through hole in the same sublayer is the same, and the volumes of the first through holes in different sublayers decrease sequentially along the stacking direction.

Optionally, each sublayer is made of the same base material, each sublayer is provided with first through holes penetrating through the sublayer, the volume of each first through hole is the same, and the number of the first through holes formed in each sublayer is equal;

the first through holes are filled with first dielectric materials, the dielectric constants of the first dielectric materials filled in the first through holes on the same sublayer are the same, and the dielectric constants of the first dielectric materials filled in the first through holes on different sublayers are sequentially increased along the stacking direction.

Optionally, the scattering layer is provided with a plurality of second through holes penetrating through the scattering layer, the second through holes are through for electromagnetic waves to pass, second dielectric materials are filled in the second through holes, and the aperture of each second through hole is smaller than the wavelength of the electromagnetic waves.

Optionally, the number and/or the aperture of the second through holes in at least one preset direction is in a trend of continuously changing, and the preset direction is any direction in the surface of the scattering layer.

Optionally, the scattering layer is provided with a plurality of second through holes penetrating through the scattering layer, the second through holes are filled with a second dielectric material, the refractive index of the second dielectric material to incident electromagnetic waves in at least one preset direction shows a variation trend of small middle and large two sides, and the preset direction is any direction in the surface of the scattering layer.

Optionally, the scattering film further includes a first protruding structure, the first protruding structure is disposed on the impedance gradual change layer on a side away from the scattering layer, the first protruding structure extends into the protective layer, and when the electromagnetic wave passes through the first protruding structure, reflection occurs.

Optionally, the first protrusion structure includes a plurality of protrusions, and a distance between adjacent protrusions is smaller than a wavelength of the electromagnetic wave.

Optionally, the scattering film further includes a connection layer, and the connection layer is disposed on a side of the scattering layer away from the impedance gradual change layer.

Optionally, the scattering film further includes a second protruding structure, the second protruding structure is disposed on one side of the scattering layer far away from the impedance gradual change layer, and the second protruding structure extends into the connection layer.

Optionally, the material of the second protrusion structure is the same as the material of the scattering layer.

In a second aspect, an embodiment of the present invention provides an electronic device, including the scattering film provided in the first aspect of the present invention, and further including an antenna device, where a surface of the antenna device is connected to the scattering film.

The scattering film provided by the embodiment of the invention comprises a scattering layer, an impedance gradual change layer and a protective layer which are sequentially stacked along the stacking direction, wherein the scattering layer is provided with a scattering structure through which electromagnetic waves can pass, so that the electromagnetic waves are diffused to the periphery after passing through the scattering structure, the space range of electromagnetic wave emission is enlarged, the function of diffusing the electromagnetic waves is realized, and a communication blind area is avoided as far as possible. By arranging the impedance gradual change layer between the scattering layer and the protective layer, the impedance of the impedance gradual change layer along the stacking direction is gradually changed from the impedance of the scattering structure to the impedance of the protective layer, so that the impedance sudden change of the interface of the scattering structure and the protective layer is eliminated, the energy loss of electromagnetic waves in the process of passing through the scattering film is reduced, and the signal transmission distance and the quality of transmission signals are improved.

Drawings

The invention is explained in more detail below with reference to the figures and examples.

FIG. 1 is a schematic diagram of a prior art diffuser film;

FIG. 2 is a cross-sectional view of a diffuser film according to an embodiment of the present invention;

FIG. 3 is a cross-sectional view of another diffuser film provided in accordance with embodiments of the present invention;

FIG. 4 is a cross-sectional view of another diffuser film provided in accordance with embodiments of the present invention;

FIG. 5 is a cross-sectional view of another diffuser film provided in accordance with embodiments of the present invention;

FIG. 6 is a cross-sectional view of another diffuser film provided in accordance with embodiments of the present invention;

FIG. 7 is a top view of a scattering layer according to an embodiment of the present invention;

FIG. 8 is a top view of another scattering layer provided by embodiments of the present invention;

FIG. 9 is a top view of another scattering layer provided by embodiments of the present invention;

FIG. 10 is a top view of another scattering layer provided by embodiments of the present invention;

fig. 11 is a cross-sectional view of an electronic device according to an embodiment of the invention;

fig. 12 is a cross-sectional view of another electronic device provided by an embodiment of the invention;

fig. 13 is a cross-sectional view of another electronic device provided in accordance with an embodiment of the present invention;

fig. 14 is a cross-sectional view of another electronic device provided by an embodiment of the invention;

fig. 15 is a cross-sectional view of another electronic device provided in an embodiment of the invention.

Description of the drawings:

110. a scattering layer; 120. a protective layer; 210. a scattering layer; 220. an impedance grading layer; 230. a protective layer; 201. a second through hole; 202. a second dielectric material; 221. a first sublayer; 222. a second sublayer; 223. a third sublayer; 203. a first through hole; 204. a first dielectric material; 240. a first bump structure; 241. a convex portion; 250. a connecting layer; 260. a second bump structure; 10. a scattering film; 20. an antenna device; 21. an antenna line; 22. a substrate.

Detailed Description

In order to make the technical problems solved, technical solutions adopted and technical effects achieved by the present invention clearer, the technical solutions of the embodiments of the present invention will be described in further detail below with reference to the accompanying drawings, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, unless expressly stated or limited otherwise, the terms "connected," "connected," and "fixed" are to be construed broadly, e.g., as meaning permanently connected, removably connected, or integral to one another; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

In the present invention, unless otherwise expressly stated or limited, "above" or "below" a first feature means that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact with each other via another feature therebetween. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.

Fig. 1 is a schematic structural view of a scattering film of the related art, which includes a scattering layer 110 and a protective layer 120, as shown in fig. 1. The protection layer 120 has a protection function, and prevents the scattering layer 110 from being damaged during the use of the scattering film. As described in the background of the present invention, after the electromagnetic wave is diffused by the scattering layer 110, a reflection phenomenon occurs at the interface between the scattering layer 110 and the protection layer 120, which results in a loss of electromagnetic energy along the propagation direction, and seriously affects the signal propagation distance and the quality of the transmission signal. The inventor has found that this is caused by the fact that the impedances of the scattering layer 110 and the protection layer 120 are different, the impedance of the two media is suddenly changed at the interface, and the reflection phenomenon is more serious when the impedance difference is larger.

Based on the above technical problem, the present embodiment provides the following solutions:

the scattering film comprises a scattering layer, an impedance gradual change layer and a protective layer which are sequentially stacked;

In order to make the technical solution of the present invention more clearly understood by those skilled in the art, the mask assembly provided in this embodiment is specifically described below with reference to the specific drawings:

an embodiment of the present invention provides a scattering film, and fig. 2 is a cross-sectional view of a scattering film provided in an embodiment of the present invention, as shown in fig. 2, the scattering film includes a scattering layer 210, an impedance-graded layer 220, and a protective layer 230, which are sequentially stacked in a Z direction.

The scattering layer 210 is made of any one metal material or two or more alloy materials selected from copper, aluminum, titanium, zinc, iron, nickel, chromium, cobalt, silver, and gold. Illustratively, in the embodiment of the present invention, the material of the scattering layer 210 is copper.

The scattering layer 210 is provided with a scattering structure through which electromagnetic waves can pass, and when the electromagnetic waves pass through the scattering layer 210, the scattering structure scatters the electromagnetic waves, so that the space range of electromagnetic wave emission is enlarged, the function of scattering the electromagnetic waves is realized, and a communication blind area is avoided as much as possible. Illustratively, the scattering structure may include a plurality of second through holes 201 penetrating through the scattering layer 210, each second through hole 201 is filled with the same or different second dielectric materials 202, the second through hole 201 may be used for passing electromagnetic waves, and the aperture of the second through hole 201 may be smaller than the wavelength of the electromagnetic waves, so that the electromagnetic waves are diffracted after being incident to the through hole, so that the propagation path of the electromagnetic waves which are originally only directionally transmitted is changed, and multiple directions of propagation paths are generated through diffraction, thereby achieving scattering of the electromagnetic waves. For example, the scattering structure may also include a plurality of second through holes 201 penetrating through the scattering layer 210, the aperture of each second through hole 201 may be larger than the wavelength of the electromagnetic wave, each second through hole 201 is filled with a different second dielectric material 202, in at least one preset direction, the refractive index of the second dielectric material 202 to the incident electromagnetic wave exhibits a trend of small middle and large two sides, and the preset direction is any direction in the surface of the scattering layer. When the electromagnetic wave passes through the scattering layer 210, the electromagnetic wave is deflected to a direction in which the refractive index is large, thereby achieving scattering of the electromagnetic wave.

The material of the protection layer 230 is an insulating material through which electromagnetic waves can pass, and has a certain impact resistance, so that the problem of short circuit caused by contact between the scattering film and other external electronic components in the use process is prevented, and the scattering film can be protected from being damaged in the use process. For example, the material of the protection layer 230 may be any one of a PPS (Polyphenylene sulfide) film layer, a PEN (Polyethylene naphthalate) film layer, a polyester film layer, a polyimide film layer, a film layer formed after curing epoxy resin ink, a film layer formed after curing polyurethane ink, a film layer formed after curing modified acrylic resin, or a film layer formed after curing polyimide resin.

The impedance of the scattering structure is a first impedance value, that is, the impedance of the second dielectric material 202 is a first impedance value, and the impedance of the protection layer 230 is a second impedance value. The impedance of the impedance gradual change layer 220 along the stacking direction (positive direction of Z) is continuously gradually changed from a first impedance value to a second impedance value, so that impedance abrupt change of an interface of the scattering structure and the protective layer is eliminated, energy loss of electromagnetic waves when the electromagnetic waves penetrate through the interface of the scattering structure and the protective layer is reduced, and signal propagation distance and transmission signal quality are improved.

Illustratively, as shown in fig. 2, the impedance-graded layer 220 is a unitary structure that continuously grades the impedance from the first impedance value to the second impedance value in the stacking direction (positive direction of Z). Illustratively, the resistance gradual change layer 220 may control the doping concentration of the substrate along the stacking direction by doping the substrate, so as to realize that the resistance of the overall structure along the stacking direction is continuously gradually changed from a first resistance value to a second resistance value.

In other embodiments of the present invention, the impedance-graded layer may not be a unitary structure, but may be formed by stacking a plurality of sub-layers, and the impedance of the plurality of sub-layers is graded from the first impedance value to the second impedance value continuously along the stacking direction. The following description will be made by way of specific examples.

Fig. 3 is a cross-sectional view of another scattering film according to an embodiment of the present invention, as shown in fig. 3, the scattering film includes a scattering layer 210, an impedance-graded layer 220, and a protective layer 230, which are sequentially stacked in a Z-direction.

The scattering layer 210 is provided with a plurality of second through holes 201 penetrating through the scattering layer 210, and the second through holes 201 are used for passing electromagnetic waves. The second through hole 201 is filled with a second dielectric material 202, and the second dielectric material 202 may be air or a material having no shielding effect on electromagnetic waves. In the embodiment of the present invention, the second dielectric material 202 is air. The aperture of the second through hole 201 is smaller than the wavelength of the electromagnetic wave, so that the electromagnetic wave is diffracted after entering the second through hole 201, the propagation path of the original electromagnetic wave which is only transmitted directionally is changed, propagation paths in multiple directions are generated through diffraction, the spatial range of electromagnetic wave emission is expanded, the function of diverging the electromagnetic wave is realized, and a communication blind area is avoided as much as possible.

The material of the protection layer 230 is an insulating material through which electromagnetic waves can pass, and has a certain impact resistance, so that the problem of short circuit caused by contact between the scattering film and other external electronic components in the use process is prevented, and the scattering film can be protected from being damaged in the use process.

The resistance of the second dielectric material 202 is a first resistance value and the resistance of the protection layer 230 is a second resistance value. Illustratively, the resistance graded layer 220 includes a first sublayer 221, a second sublayer 222, and a third sublayer 223 that are sequentially stacked in a stacking direction. Each sublayer is made of a different substrate, and the impedance of each substrate is gradually changed from a first impedance value to a second impedance value along the stacking direction. Specifically, the impedance of the substrate of the first sub-layer 221 in contact with the scattering layer 210 is a first impedance value, and the impedance of the substrate of the third sub-layer 223 in contact with the protection layer 230 is a second impedance value, so that the impedances of the first sub-layer 221 to the third sub-layer 223 gradually change along the stacking direction. The impedance of the impedance gradual change layer along the stacking direction is continuously gradually changed from a first impedance value to a second impedance value, so that the impedance sudden change of the interface of the scattering structure and the protective layer is eliminated, the energy loss of the electromagnetic wave when the electromagnetic wave penetrates through the interface of the scattering structure and the protective layer is reduced, and the signal transmission distance and the quality of transmission signals are improved.

In the above embodiment, each sub-layer is made of a different substrate, and the impedance of each substrate is gradually changed along the stacking direction, so that the impedances of the first sub-layer to the nth sub-layer are gradually changed along the stacking direction. In other embodiments of the present invention, each sub-layer may also be made of the same base material, each sub-layer is provided with a plurality of first through holes penetrating through the sub-layer, the volume of the first through holes on the same sub-layer is the same, and the volumes and/or the numbers of the first through holes on different sub-layers are different, so that the impedances of the first sub-layer to the nth sub-layer gradually change along the stacking direction. The concrete description is as follows:

fig. 4 is a cross-sectional view of another scattering film according to an embodiment of the present invention, as shown in fig. 4, the scattering film includes a scattering layer 210, an impedance-graded layer 220, and a protective layer 230, which are sequentially stacked in a Z-direction.

The resistance of the second dielectric material 202 is a first resistance value and the resistance of the protection layer 230 is a second resistance value. Illustratively, the resistance graded layer 220 includes a first sublayer 221, a second sublayer 222, and a third sublayer 223 that are sequentially stacked in a stacking direction. Each sublayer is made of the same base material, each sublayer is provided with first through holes 203 penetrating through the sublayer, and the plurality of first through holes 203 are arranged in an array along the X direction and the Y direction, wherein the X direction and the Y direction are two directions which are perpendicular to each other in a plane where the impedance gradient layer 220 is located. The volumes of the first through holes 203 are the same, and the number of the first through holes 203 on different sub-layers is sequentially reduced along the stacking direction, so that the impedance of each sub-layer gradually changes from the first impedance value to the second impedance value along the stacking direction. Specifically, the number of the first through holes 203 on the first sublayer 211 is the largest, so that the equivalent impedance of the first sublayer 221 is equal to or close to the first impedance value, the number of the first through holes 203 on the third sublayer 223 is the smallest, so that the equivalent impedance of the third sublayer 223 is equal to or close to the second impedance value, and the number of the first through holes 203 on different sublayers decreases in sequence along the stacking direction, so that the equivalent impedances of the first sublayer 221 to the third sublayer 223 gradually change along the stacking direction. The impedance of the impedance gradual change layer along the stacking direction is continuously gradually changed from a first impedance value to a second impedance value, so that the impedance sudden change of the interface of the scattering structure and the protective layer is eliminated, the energy loss of the electromagnetic wave when the electromagnetic wave penetrates through the interface of the scattering structure and the protective layer is reduced, and the signal transmission distance and the quality of transmission signals are improved.

Fig. 5 is a cross-sectional view of another scattering film according to an embodiment of the present invention, as shown in fig. 5, the scattering film includes a scattering layer 210, an impedance-graded layer 220, and a protective layer 230, which are sequentially stacked in a Z-direction.

The resistance of the second dielectric material 202 is a first resistance value and the resistance of the protection layer 230 is a second resistance value. Illustratively, the resistance graded layer 220 includes a first sublayer 221, a second sublayer 222, and a third sublayer 223 that are sequentially stacked in a stacking direction. Each sublayer is made of the same base material, each sublayer is provided with first through holes 203 penetrating through the sublayer, and the plurality of first through holes 203 are arranged in an array along the X direction and the Y direction, wherein the X direction and the Y direction are two directions which are perpendicular to each other in a plane where the impedance gradient layer 220 is located. The number of the first through holes 203 formed in each sub-layer is equal, the volume of each first through hole 203 in the same sub-layer is the same, and the volume of the first through holes 203 in different sub-layers is sequentially reduced along the stacking direction, so that the impedance of each sub-layer gradually changes from the first impedance value to the second impedance value along the stacking direction. Specifically, the volume of the first through hole 203 on the first sublayer 211 is the largest, so that the equivalent impedance of the first sublayer 221 is equal to or close to the first impedance value, the volume of the first through hole 203 on the third sublayer 223 is the smallest, so that the equivalent impedance of the third sublayer 223 is equal to or close to the second impedance value, and the volumes of the first through holes 203 on different sublayers decrease in sequence along the stacking direction, so that the equivalent impedances of the first sublayer 221 to the third sublayer 223 gradually change along the stacking direction. The impedance of the impedance gradual change layer along the stacking direction is continuously gradually changed from a first impedance value to a second impedance value, so that the impedance sudden change of the interface of the scattering structure and the protective layer is eliminated, the energy loss of the electromagnetic wave when the electromagnetic wave penetrates through the interface of the scattering structure and the protective layer is reduced, and the signal transmission distance and the quality of transmission signals are improved.

In the above embodiment, each sub-layer is made of the same base material, and the first through holes with different apertures and/or different numbers are formed in each sub-layer, so that the impedances of the first sub-layer to the nth sub-layer gradually change along the stacking direction. In other embodiments of the present invention, different first dielectric materials may be filled in the first through holes of the sub-layers, so that the impedances of the first sub-layer to the nth sub-layer gradually change along the stacking direction. The concrete description is as follows:

fig. 6 is a cross-sectional view of another scattering film according to an embodiment of the present invention, as shown in fig. 6, the scattering film includes a scattering layer 210, an impedance-graded layer 220, and a protective layer 230, which are sequentially stacked in a Z-direction.

The resistance of the second dielectric material 202 is a first resistance value and the resistance of the protection layer 230 is a second resistance value. Illustratively, the resistance graded layer 220 includes a first sublayer 221, a second sublayer 222, and a third sublayer 223 that are sequentially stacked in a stacking direction. Each sublayer is made of the same base material, each sublayer is provided with first through holes 203 penetrating through the sublayer, and the plurality of first through holes 203 are arranged in an array along the X direction and the Y direction, wherein the X direction and the Y direction are two directions which are perpendicular to each other in a plane where the impedance gradient layer 220 is located. The number of the first through holes 203 formed in each sub-layer is equal, and the volumes of the first through holes 203 are the same. The first via holes 203 are filled with a first dielectric material 204, the dielectric constants of the first dielectric materials 204 filled in the first via holes 203 on the same sub-layer are the same, and the dielectric constants of the first dielectric materials 204 filled in the first via holes 203 on different sub-layers are sequentially increased along the stacking direction. As shown in fig. 6, the filled first dielectric material 204 is shaded in the first via 203, and the higher the shading density is, the higher the dielectric constant of the first dielectric material 204 is.

As known to those skilled in the art, the dielectric constant of a medium is directly related to impedance, and the higher the dielectric constant of the medium is, the higher the impedance is. The dielectric constants of the first dielectric materials 204 filled in the first through holes 203 on different sub-layers are sequentially increased along the stacking direction, so that the equivalent impedance of each sub-layer gradually changes from a first impedance value to a second impedance value along the stacking direction. Specifically, the dielectric constant of the first dielectric material 204 filled in the first via 203 on the first sublayer 221 is the smallest, so that the equivalent impedance of the first sublayer 221 is equal to or close to the first impedance value, the dielectric constant of the first dielectric material 204 filled in the first via 203 on the third sublayer 223 is the largest, so that the equivalent impedance of the third sublayer 223 is equal to or close to the second impedance value, and the dielectric constants of the first dielectric materials 204 in the first vias 203 on different sublayers sequentially increase along the stacking direction, so that the equivalent impedances of the first sublayer 221 to the third sublayer 223 gradually change along the stacking direction. The impedance of the impedance gradual change layer along the stacking direction is continuously gradually changed from a first impedance value to a second impedance value, so that the impedance sudden change of the interface of the scattering structure and the protective layer is eliminated, the energy loss of the electromagnetic wave when the electromagnetic wave penetrates through the interface of the scattering structure and the protective layer is reduced, and the signal transmission distance and the quality of transmission signals are improved.

Illustratively, the first dielectric material 204 filled in the first through hole 203 of each sub-layer along the stacking direction may be air, glass, sodium chloride, polystyrene, quartz, crystal, copper oxide, iodine crystal, or the like.

It should be noted that, in the foregoing embodiment, the impedance gradual change layer includes three sublayers as an example to describe the present invention, the number of sublayers included in the impedance gradual change layer is not limited in the embodiment of the present invention, and in other embodiments of the present invention, the impedance gradual change layer may also include more than four sublayers. It will be clear to a person skilled in the art that the higher the number of sublayers the graded-impedance layer comprises, the more gradual the graded-impedance layer has, the better the effect of eliminating abrupt impedance changes at the interface between the scattering structure and the protective layer. The number of sublayers of the resistance-graded layer may be 3 to 10 layers in consideration of the production cost.

In the above embodiment, the cross-sectional shapes of the second through hole and the first through hole are not limited, and the cross-sectional areas of the through holes cut on any cross section perpendicular to the Z direction may be the same or different. In some embodiments of the present invention, in order to facilitate the formation of the through hole, the cross-sectional shapes of the second through hole and the first through hole may be regular shapes such as a circle, a square, and the like, and the cross-sectional area of the through hole is the same in any cross section perpendicular to the Z direction.

On the basis of the above embodiment, the scattering structure arranged on the scattering layer may include a plurality of second through holes penetrating through the scattering layer, the second through holes may allow electromagnetic waves to pass through, the second through holes are filled with a second dielectric material, and the aperture of the second through holes is smaller than the wavelength of the electromagnetic waves, so that the electromagnetic waves are diffracted after being incident to the second through holes, thereby changing the propagation path of the original electromagnetic waves which are only directionally transmitted, generating propagation paths in a plurality of directions through diffraction, expanding the spatial range of electromagnetic wave transmission, thereby implementing the function of diverging the electromagnetic waves, and avoiding the communication blind area as much as possible.

Furthermore, the number and/or the aperture of the second through holes in the preset direction of the scattering layer tend to change continuously, the preset direction is any direction in the surface of the scattering layer, the disorder of the diffraction of the electromagnetic waves is enhanced, and the space range of the emission of the electromagnetic waves is further enlarged. The concrete description is as follows:

fig. 7 is a top view of a scattering layer according to an embodiment of the present invention, as shown in fig. 7, a plurality of second through holes 201 penetrating through the scattering layer 210 are formed in the scattering layer 210, and the plurality of second through holes 201 are arranged in an array. Specifically, the plurality of second through holes 201 are arranged in an array along the X direction and the Y direction on the surface of the scattering layer 210, the second through holes 201 are cylindrical through holes, and the aperture of the plurality of second through holes 201 shows a variation trend of large middle and small two sides along the X direction. The aperture of the second through hole 201 is set to have a variation trend of large middle and small two sides along the X direction, so that the disorder of the diffraction of the electromagnetic waves is enhanced, and the emission space range of the electromagnetic waves is further enlarged.

The second through hole 201 is filled with a second dielectric material 202, and the second dielectric material 202 may be air or a material having no shielding effect on electromagnetic waves. In the embodiment of the present invention, the second dielectric material 202 is air.

In the above embodiment, the apertures of the second through holes 201 have a variation trend with a large middle and small two sides along the X direction, and in other embodiments of the present invention, the apertures of the second through holes 201 may also have another variation trend along the X direction, for example, along the X direction, the apertures of the second through holes 201 have a variation trend with a small middle and large two sides, and continuously increasing or continuously decreasing, which can also achieve the technical effects of the present invention, and the embodiments of the present invention are not described herein again.

Fig. 8 is a top view of another scattering layer according to an embodiment of the present invention, and as shown in fig. 8, a plurality of second through holes 201 penetrating through the scattering layer 210 are formed in the scattering layer 210, and the second through holes 201 are arranged in an array. Specifically, the plurality of second through holes 201 are arranged in an array along the X direction and the Y direction on the surface of the scattering layer 210, the second through holes 201 are cylindrical through holes, the plurality of second through holes 201 have the same aperture, and the number of the second through holes 201 shows a trend of change with more middle and less two sides along the X direction. That is, along the X direction, the second through holes 201 in the middle are arranged more densely, and the second through holes 201 on both sides are arranged sparsely. The number of the second through holes 201 is changed along the X direction, so that the disorder of the diffraction of the electromagnetic waves is enhanced, and the emission space range of the electromagnetic waves is further enlarged.

In the above embodiment, the number of the second through holes 201 shows a trend of more middle and less two sides along the X direction. In other embodiments of the present invention, along the X direction, the number of the second through holes 201 may also be unequal, for example, a variation trend with a small middle and a large number of two sides, a variation trend with a continuous increase or a reduction is presented, and the technical effect of the present invention can also be achieved, and the embodiments of the present invention are not described herein again.

In the above embodiment, the technical solution of the present invention is described by taking as an example that the second dielectric materials in the second through holes are the same dielectric material, and in other embodiments of the present invention, the second dielectric materials in the second through holes may also be different dielectric materials, for example, in at least one preset direction, the refractive index of the second dielectric material to the incident electromagnetic wave shows a tendency of small change in the middle and large change in the two sides, and the preset direction is an arbitrary direction in the surface of the scattering layer. The concrete description is as follows:

fig. 9 is a top view of another scattering layer according to an embodiment of the present invention, as shown in fig. 9, a plurality of second through holes 201 penetrating through the scattering layer 210 are formed in the scattering layer 210, and the second through holes 201 are arranged in an array. Specifically, the plurality of second through holes 201 are arranged in an array along the X direction and the Y direction on the surface of the scattering layer 210, the second through holes 201 are cylindrical through holes, and the aperture of the plurality of second through holes 201 shows a variation trend of small middle and large two sides along the X direction. The aperture of the second through hole 201 is set to have a variation trend of small middle and large two sides along the X direction, so that the disorder of the diffraction of the electromagnetic waves is enhanced, and the emission space range of the electromagnetic waves is further enlarged.

Along the X direction, each second through hole 201 is filled with a different second dielectric material 202, and along the X direction, the refractive index of the second dielectric material 202 filled in each second through hole 201 shows a variation trend of being small in the middle and large on both sides, so that the whole scattering layer 210 shows a variation trend of being low in the middle and high on both sides for the refractive index of the electromagnetic wave in the X direction, thereby realizing the divergence of the electromagnetic wave. Illustratively, iodine crystals, copper oxide, crystal, quartz, polystyrene, sodium chloride, glass, air, glass, sodium chloride, polystyrene, quartz, crystal, copper oxide, iodine crystals are filled in sequence along the X direction. As shown in fig. 9, the filled second dielectric material 202 is shaded in the second through hole 201, and the greater the shading density, the greater the refractive index of the second dielectric material 202.

In the above embodiment, the apertures of the second through holes 201 have a variation trend with a small middle and large two sides along the X direction, in other embodiments of the present invention, the apertures of the second through holes 201 may also have another variation trend along the X direction, for example, along the X direction, the apertures of the second through holes 201 have a variation trend with a large middle and small two sides, continuously increasing or continuously decreasing, which can also achieve the technical effect of the present invention, and the embodiments of the present invention are not described herein again.

In the above embodiments, the scattering structure disposed on the scattering layer includes a plurality of second through holes penetrating through the scattering layer, and the aperture of the second through hole is smaller than the wavelength of the electromagnetic wave. In other embodiments of the present invention, the scattering structure disposed on the scattering layer may include a plurality of second through holes penetrating through the scattering layer, an aperture of each second through hole is larger than a wavelength of the electromagnetic wave, a second dielectric material is filled in each second through hole, the refractive index of the second dielectric material to the incident electromagnetic wave shows a trend of small middle and large side changes in at least one preset direction, and the preset direction is any direction in the surface of the scattering layer. The concrete description is as follows:

fig. 10 is a top view of another scattering layer according to an embodiment of the present invention, as shown in fig. 10, a plurality of second through holes 201 penetrating through the scattering layer 210 are formed in the scattering layer 210, and an aperture of each second through hole 201 is larger than a wavelength of an electromagnetic wave. The plurality of second through holes 201 are arranged in an array, specifically, the plurality of second through holes 201 are arranged in an array along the X direction and the Y direction on the surface of the scattering layer 210, the second through holes 201 are cylindrical through holes, the plurality of second through holes 201 have the same aperture, and the second through holes 201 are arranged in the same distance along the X direction.

Along the X direction, each second through hole 201 is filled with a different second dielectric material 202, and along the X direction, the refractive index of the second dielectric material 202 filled in each second through hole 201 shows a variation trend of being small in the middle and large on both sides, so that the whole scattering layer 210 shows a variation trend of being low in the middle and high on both sides for the refractive index of the electromagnetic wave in the X direction, thereby realizing the divergence of the electromagnetic wave. Illustratively, iodine crystals, copper oxide, crystal, quartz, polystyrene, sodium chloride, glass, air, glass, sodium chloride, polystyrene, quartz, crystal, copper oxide, iodine crystals are filled in sequence along the X direction. As shown in fig. 10, the filled second dielectric material 202 is shaded in the second through hole 201, and the greater the shading density, the greater the refractive index of the second dielectric material 202.

In this case, the second through holes 201 no longer have a diffraction effect on the electromagnetic waves, and the refractive index of the dielectric material 202 filled in each second through hole 201 in the X direction shows a tendency of small middle and large two sides, so that the refractive index of the electromagnetic wave in the X direction of the whole scattering layer 210 shows a tendency of low middle and high two sides, and when the electromagnetic wave passes through the scattering layer 210, the electromagnetic wave is deflected to the direction with the larger refractive index, thereby realizing the scattering of the electromagnetic wave.

On the basis of the above embodiments, as shown in fig. 2 to fig. 6, the scattering film may further include a first protrusion structure 240, the first protrusion structure 240 is disposed on the impedance gradual change layer 220 on a side away from the scattering layer 210, and the first protrusion structure 240 extends into the protection layer 230, that is, the protection layer 230 covers the first protrusion structure 240. When the electromagnetic wave is emitted through the first protrusion structure 240, diffuse reflection occurs, so that the movement path of the original electromagnetic wave which is only directionally transmitted is changed, and a transmission path in multiple directions is generated through the diffuse reflection, thereby further expanding the divergence range of the electromagnetic wave. For the material for realizing the electromagnetic wave reflection function, the first protrusion structure 240 made of metal is preferably used in the present invention, but the present invention is not limited thereto, and any material capable of realizing the electromagnetic wave reflection function may be applied to the present invention, and for example, the first protrusion structure 240 made of alloy may be used.

The first protrusion structure 240 extends into the protection layer 230, so as to improve the connection reliability between the impedance gradual change layer 220 and the protection layer 230, and prevent the protection layer 230 and the impedance gradual change layer 220 from peeling off. The height of the first bump structures 240 is smaller than the thickness of the protection layer 230, and the design ensures that the first bump structures 240 extend into the protection layer 230 but not extend out of the protection layer 230, so as to prevent the protection layer 230 from failing. It should be noted that, when the first protruding structure 240 includes a plurality of protruding portions 241 with different heights, the height of the first protruding structure 240 at this time refers to the highest height of all the protruding portions 241. Illustratively, the thickness of the protective layer 230 is 1 μm to 25 μm, and the height of the first bump structure 240 is 0.1 μm to 15 μm.

For example, the first protrusion structure 240 may include a plurality of protrusions 241 to improve a diffuse reflection effect. The distance between adjacent protrusions 241 is smaller than the wavelength of the electromagnetic wave, and illustratively, the distance between adjacent protrusions 241 is 0 μm to 500 μm. The adjacent protrusions 241 may be connected to each other or may be spaced apart from each other. The size of the convex portion 241 is not particularly limited in the present invention, and the plurality of convex portions 241 may be the same size or different sizes.

In an embodiment of the present invention, the shape of the first protrusion structure 240 may have a variety according to actual needs, and may be a regular or irregular solid geometry, which is not limited herein. In some examples, the first protrusion structures 240 are one or more of pointed, inverted conical, granular, dendritic, columnar, and massive in shape. For example, as shown in the examples of fig. 2-6, the first protruding structure 240 is an irregular curved shape.

In order to facilitate connection of the diffusion film of the present invention with other components, as shown in fig. 2 to 6, the diffusion film may further include a connection layer 250, and the connection layer 250 is disposed on the diffusion layer 210 to cover a side away from the impedance-gradient layer 220. Illustratively, the tie layer 250 is a glue film layer. Through setting up the glued membrane layer, can make the scattering film of this embodiment realize being connected with other parts easily. Illustratively, the material used for the adhesive film layer is selected from any one of the following materials: epoxy resin, modified epoxy resin, acrylic acid, modified rubber, thermoplastic polyimide, modified thermoplastic polyimide, polyurethane, polyacrylate, and silicone.

In some embodiments of the present invention, as shown in fig. 2 to 6, the scattering film may further include a second protrusion structure 260, and the second protrusion structure 260 is disposed on a side of the scattering layer 210 away from the impedance gradual change layer 220. The second protrusion structures 260 extend into the connection layer 250, so that the connection reliability between the scattering layer 210 and the connection layer 250 is improved, and the connection layer 250 and the scattering layer 210 are prevented from being peeled off. The connection layer 250 covers all of the second bump structures 260, and therefore, the height of the second bump structures 260 of the present embodiment is less than or equal to the thickness of the connection layer 250. By the design it is ensured that the second bump structures 260 extend into the connection layer 250, but not out of the connection layer 250. It should be noted that the shapes of the second protrusion structures 260 in fig. 2-6 are merely exemplary, and due to differences in process means and parameters, the shapes of the second protrusion structures 260 are regular or irregular solid geometries, for example, the shapes of the second protrusion structures 260 may be one or more of sharp-angled, inverted-tapered, granular, dendritic, columnar, and massive. The second bump structures 260 in the embodiment of the invention are not limited to the shapes shown in the drawings and described above, and any second bump structures 260 that are advantageous for improving the connection stability between the connection layer 250 and the scattering layer 210 are within the scope of the invention. The shapes of the plurality of second protrusion structures 260 may be the same or different, and the sizes of the second protrusion structures 260 may also be the same or different, that is, the shapes of the plurality of second protrusion structures 260 may be one or more of pointed, inverted conical, granular, dendritic, columnar, and blocky, and the sizes of the plurality of second protrusion structures 260 of the same shape may not be completely the same. In addition, the plurality of second protrusion structures 260 are continuously or discontinuously distributed on the side of the scattering layer 210 close to the connection layer 250, for example, when the plurality of second protrusion structures 260 are in the shape of sharp corners and are continuously distributed, a regular and periodic three-dimensional insection pattern or an irregular and disordered three-dimensional insection pattern can be formed.

It should be noted that the heights of the plurality of second protruding structures 260 may be different, and in this case, the height of the second protruding structure 260 refers to the highest height of all the second protruding structures 260. The outer surface of the connection layer 250 and the surface of the scattering layer 210 may be a flat surface without undulation or a non-flat surface with gentle undulation, which is not limited in the embodiment of the present invention.

In some embodiments of the present invention, the second bump structures 260 are made of a conductive material, so that during the use of the scattering film, the interference charges accumulated in the scattering layer 210 are led out, thereby preventing the accumulation of the interference charges from forming an interference source. Illustratively, the scattering layer 210 and the second bump structures 260 are integrally formed of the same metal material. When connected to other components, the second bump structures 260 are pressed to pierce the connection layer 250 and to be grounded, so as to conduct out the interference charges accumulated in the diffusion layer 210.

In the embodiment of the present invention, the height of the second bump structures 260 is preferably 0.1 μm to 30 μm, and the thickness of the connection layer 250 is preferably 0.1 μm to 45 μm, so as to ensure that the second bump structures 260 can pierce the connection layer 250 when the diffuser film is used, thereby ensuring that the diffuser film can be grounded.

In order to adapt to more application scenes, the scattering film disclosed by the invention is of a flexible, foldable and bendable structure. Specifically, the scattering film of the present invention can have foldable and bendable properties by using a flexible structure of the scattering layer 210, the impedance gradation layer 220, and the protection layer 230, for example, an FPC board, and the connection layer 250 for connection provided on one surface of the scattering layer 210 has a bendable property. In actual use, the scattering film may be bent or folded into any shape such as a ring structure or a semi-closed structure, for example, an arc structure, an oval structure, or a stacked structure, as required.

Fig. 11 is a cross-sectional view of an electronic device according to an embodiment of the present invention, fig. 12 is a cross-sectional view of another electronic device according to an embodiment of the present invention, fig. 13 is a cross-sectional view of another electronic device according to an embodiment of the present invention, fig. 14 is a cross-sectional view of another electronic device according to an embodiment of the present invention, and fig. 15 is a cross-sectional view of another electronic device according to an embodiment of the present invention, as shown in fig. 11 to 15, the electronic device includes a scattering film 10 and an antenna device 20. The antenna device 20 includes an antenna line 21 and a substrate 22 on which the antenna line 21 is disposed.

The diffusion film 10 includes a diffusion layer 210, an impedance-graded layer 220, and a protective layer 230 stacked in this order in the stacking direction (positive direction of Z).

The scattering layer 210 is provided with a plurality of second through holes 201 penetrating through the scattering layer 210, the second through holes 201 are filled with a second dielectric material 202, and the second through holes 201 can allow electromagnetic waves to pass through. The aperture of the second through hole 201 is smaller than the wavelength of the electromagnetic wave, so that the electromagnetic wave is diffracted after entering the second through hole 201, the propagation path of the original electromagnetic wave which is only transmitted directionally is changed, propagation paths in multiple directions are generated through diffraction, the spatial range of electromagnetic wave emission is expanded, the function of diverging the electromagnetic wave is realized, and a communication blind area is avoided as much as possible. The number and/or aperture of the second through holes in the X direction of the scattering layer 210 tends to change continuously, which enhances the disorder of the diffraction of the electromagnetic wave and further increases the spatial range of the emission of the electromagnetic wave.

The impedance of the impedance-gradient layer 220 in the stacking direction is gradually changed from the first impedance of the scattering structure (the second dielectric material 202) to the second impedance of the protection layer 230, so that the impedance mutation at the interface between the scattering structure and the protection layer 230 is eliminated, the energy loss of the electromagnetic wave in the process of passing through the scattering film is reduced, and the signal propagation distance and the quality of the transmission signal are improved.

Illustratively, as shown in fig. 11, the impedance-graded layer 220 is a unitary structure in which the impedance in the stacking direction (positive direction of Z) is graded continuously from a first impedance value to a second impedance value.

Illustratively, as shown in fig. 12, the resistance graded layer 220 includes a first sublayer 221, a second sublayer 222, and a third sublayer 223 that are sequentially stacked in a stacking direction. Each sublayer is made of a different substrate, and the impedance of each substrate is gradually changed from a first impedance value to a second impedance value along the stacking direction.

Illustratively, as shown in fig. 13, the resistance graded layer 220 includes a first sublayer 221, a second sublayer 222, and a third sublayer 223 that are sequentially stacked in a stacking direction. Each sublayer is made of the same base material, each sublayer is provided with a first through hole 203 penetrating through the sublayer, the volume of each first through hole 203 is the same, and the number of the first through holes 203 on different sublayers is sequentially reduced along the stacking direction, so that the impedance of each sublayer gradually changes from the first impedance value to the second impedance value along the stacking direction.

Illustratively, as shown in fig. 14, the resistance graded layer 220 includes a first sublayer 221, a second sublayer 222, and a third sublayer 223 that are sequentially stacked in a stacking direction. Each sublayer is made of the same base material, each sublayer is provided with first through holes 203 penetrating through the sublayer, the number of the first through holes 203 formed in each sublayer is equal, the volume of each first through hole 203 in the same sublayer is the same, and the volume of the first through holes 203 in different sublayers is sequentially reduced along the stacking direction, so that the impedance of each sublayer gradually changes from a first impedance value to a second impedance value along the stacking direction.

Illustratively, as shown in fig. 15, the resistance graded layer 220 includes a first sublayer 221, a second sublayer 222, and a third sublayer 223 that are sequentially stacked in a stacking direction. Each sublayer is made of the same base material, each sublayer is provided with first through holes 203 penetrating through the sublayer, the number of the first through holes 203 formed in each sublayer is equal, and the volume of each first through hole 203 is the same. The first via holes 203 are filled with a first dielectric material 204, the dielectric constants of the first dielectric materials 204 filled in the first via holes 203 on the same sub-layer are the same, and the dielectric constants of the first dielectric materials 204 filled in the first via holes 203 on different sub-layers are sequentially increased along the stacking direction, so that the impedance of each sub-layer gradually changes from the first impedance value to the second impedance value along the stacking direction.

The diffusion film 10 further includes a first protrusion structure 240 disposed on the first surface of the impedance gradual change layer 220, the first protrusion structure 240 includes a plurality of protrusions 241, and the first protrusion structure 240 extends into the protection layer 230. The diffusion film 10 further includes a second protrusion structure 260 and a connection layer 250 disposed on the diffusion layer 210, the second protrusion structure 260 protruding into the connection layer 250.

The connection between the antenna device 20 and the diffusion film 10 is achieved by bonding and connecting one surface of the substrate 22 to the connection layer 250 of the diffusion film 10. By connecting the scattering film 10 to the antenna device 20.

In the description herein, it is to be understood that the terms "upper", "lower", "right", and the like are based on the orientations and positional relationships shown in the drawings and are used for convenience in description and simplicity in operation, but do not indicate or imply that the referenced devices or elements must have a particular orientation, be constructed in a particular orientation, and be constructed in a particular operation, and thus should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used merely for descriptive purposes and are not intended to have any special meaning.

In the description herein, references to the description of "an embodiment," "an example" or the like are intended to mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example.

Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be appropriately combined to form other embodiments as will be appreciated by those skilled in the art.

The technical principle of the present invention is described above in connection with specific embodiments. The description is made for the purpose of illustrating the principles of the invention and should not be construed in any way as limiting the scope of the invention. Based on the explanations herein, those skilled in the art will be able to conceive of other embodiments of the present invention without inventive effort, which would fall within the scope of the present invention.

Claims

1. A scattering film is characterized by comprising a scattering layer, an impedance gradual change layer and a protective layer which are sequentially stacked along a stacking direction;

2. The diffuser film of claim 1, wherein the impedance-graded layer comprises n sublayers, namely a first sublayer to an nth sublayer stacked in sequence along the stacking direction, the impedance of the first sublayer in contact with the diffuser layer is a first impedance value, the impedance of the nth sublayer in contact with the protective layer is a second impedance value, and the impedances of the first sublayer to the nth sublayer are graded along the stacking direction, wherein n is greater than or equal to 3.

3. The diffuser film of claim 2, wherein each of the sub-layers is made of a different substrate, and wherein the impedance of each of the substrates is graded in the stacking direction.

4. The diffuser film according to claim 2, wherein each of the sub-layers is made of the same base material, each of the sub-layers is provided with a plurality of first through holes penetrating through the sub-layer, the first through holes on the same sub-layer have the same volume, and the first through holes on different sub-layers have different volumes and/or different numbers, so that the impedances of the first sub-layer to the nth sub-layer gradually change along the stacking direction.

5. The diffuser film of claim 4, wherein the volume between the first through holes of each sub-layer is the same, and the number of the first through holes of different sub-layers decreases sequentially along the stacking direction.

6. The diffuser film of claim 4, wherein the number of the first through holes formed in each of the sub-layers is equal, the volume of each of the first through holes in the same sub-layer is equal, and the volumes of the first through holes in different sub-layers decrease sequentially along the stacking direction.

7. The scattering film of claim 2, wherein each sublayer is made of the same base material, each sublayer is provided with first through holes penetrating through the sublayer, the volume of each first through hole is the same, and the number of the first through holes provided on each sublayer is equal;

8. The scattering film of any of claims 1-7, wherein the scattering layer has a plurality of second through holes formed therethrough, the second through holes being configured to allow electromagnetic waves to pass therethrough, the second through holes being filled with a second dielectric material, and the second through holes having a smaller aperture than the wavelength of the electromagnetic waves.

9. The diffuser film of claim 8, wherein the number and/or aperture of the second through holes has a continuously changing trend in at least one predetermined direction, the predetermined direction being any direction within the surface of the diffuser layer.

10. The scattering film according to any one of claims 1 to 7, wherein the scattering layer is provided with a plurality of second through holes penetrating through the scattering layer, the second through holes are filled with a second dielectric material, the refractive index of the second dielectric material to incident electromagnetic waves shows a trend of small change in the middle and large change in the two sides in at least one preset direction, and the preset direction is any direction in the surface of the scattering layer.

11. The scattering film of claim 1, further comprising a first protrusion structure disposed on a side of the impedance-graded layer away from the scattering layer, wherein the first protrusion structure protrudes into the protective layer and reflects electromagnetic waves passing through the first protrusion structure.

12. The diffuser film of claim 11, wherein the first raised structure comprises a plurality of raised portions, and wherein a distance between adjacent raised portions is less than a wavelength of the electromagnetic wave.

13. The diffuser film of claim 1, further comprising a connection layer disposed on a side of the diffuser layer distal from the impedance grading layer.

14. The diffuser film of claim 13, further comprising a second protrusion structure disposed on a side of the diffuser layer away from the graded impedance layer, the second protrusion structure protruding into the connection layer.

15. The diffuser film of claim 14, wherein the second raised structures are made of the same material as the diffuser layer.

16. An electronic device comprising the diffuser film of any of claims 1-15, and further comprising an antenna assembly, a surface of the antenna assembly being coupled to the diffuser film.