Preparation method and device of metamaterial wave absorber transparent to visible light

Abstract

The invention relates to the technical field of materials, discloses a preparation method and device of a visible-light-transparent metamaterial wave absorber, and solves the problems that an existing preparation method and device of the visible-light-transparent metamaterial wave absorber are narrow in wave absorbing bandwidth, poor in visible light transparency and difficult to achieve an infrared camouflage effect. The infrared stealth layer, the first PMMA layer, the microwave absorption layer, the second PMMA layer and the microwave reflection layer are combined and arranged by utilizing the visible light transparency characteristic of the indium tin oxide thin film and the polymethyl methacrylate or the polyvinyl chloride plate, the indium tin oxide with resistance loss is used as an absorbent, electromagnetic resonance loss is introduced, and meanwhile the resistance loss is increased; the adjustable resistance and patterning characteristics of the indium tin oxide are fully utilized, the duty ratio of the high-conductivity indium tin oxide thin film in the infrared stealth layer is improved, the infrared emissivity can be reduced, and the transparent indium tin oxide thin film with different surface resistivity is utilized to realize broadband strong absorption of visible light transparency and infrared disguise.

Description

Technical Field

[0001] The present invention relates to the field of material technology, and in particular to a method and device for preparing a visible light transparent metamaterial absorber. Background Art

[0002] As an important part of metamaterial research, metamaterial absorbers have become a research hotspot in the fields of radar radio frequency stealth and electromagnetic compatibility and shielding of electronic information systems due to their advantages such as compact structure, light weight, ultra-thinness and easy integration with electronic equipment. They have high application value. Metamaterial absorbers that are transparent to visible light and compatible with infrared camouflage have more extensive applications, and are more widely used in equipment that requires electromagnetic protection, such as aircraft cockpit observation windows, hospital medical equipment and electronic LCD screens.

[0003] The electromagnetic wave absorption performance of metamaterial absorbers mainly depends on the pattern and material composition of the periodic structure. The pattern components of metamaterial absorbers on the market are mainly conductive metal structures. In order to improve the electromagnetic wave absorption performance of the absorber, the conductive metal needs to be structurally designed. The corresponding metamaterial absorber has a narrow electromagnetic wave absorption bandwidth and it is difficult to meet the needs of strong broadband absorption. In addition, metal-based metamaterial absorbers have poor visible light transparency and cannot be used in some specific occasions. At the same time, it is difficult to achieve infrared camouflage effects.

[0004] In order to solve the above problems, an innovative design is carried out based on the original preparation method and device of visible light transparent metamaterial absorber. Summary of the invention

[0005] The purpose of the present invention is to provide a method and device for preparing a visible light transparent metamaterial absorber. By adopting the device to work, the problems of the existing method and device for preparing a visible light transparent metamaterial absorber, such as narrow absorption bandwidth, poor visible light transparency and difficulty in achieving infrared camouflage effect, are solved.

[0006] To achieve the above object, the present invention provides the following technical solution: a visible light transparent metamaterial absorber device, comprising: an infrared stealth layer, a first PMMA layer, a microwave absorption layer, a second PMMA layer and a microwave reflection layer;

[0007] The infrared stealth layer, microwave absorption layer and microwave reflection layer are indium tin oxide thin films with different resistivities prepared by magnetron sputtering on a polyethylene terephthalate film base. The infrared stealth layer is used to reduce the infrared emissivity to achieve infrared stealth and work in conjunction with the microwave absorption layer. The microwave absorption layer is used to absorb electromagnetic waves in the microwave frequency band. The microwave reflection layer is used to reflect microwaves to cooperate with the microwave absorption layer to adjust the wave absorption effect. At the same time, due to its material properties, it assists in achieving infrared stealth.

[0008] The first PMMA layer and the second PMMA layer are both plate-like components made of polymethyl methacrylate or polyvinyl chloride. The first PMMA layer is used to separate the infrared stealth layer and the microwave absorption layer while ensuring the transmittance of visible light. The second PMMA layer is used to separate the microwave absorption layer and the microwave reflection layer while also ensuring the transmittance of visible light.

[0009] Furthermore, the infrared stealth layer is a low-resistivity infrared emissivity indium tin oxide patterned film, the microwave absorption layer is a high-resistivity indium tin oxide patterned film, and the microwave reflection layer is a low-resistance indium tin oxide film.

[0010] A method for preparing a visible light transparent metamaterial absorber comprises the following steps:

[0011] S1: Using polyethylene terephthalate film as substrate, indium tin oxide thin films with different resistivities were prepared by magnetron sputtering;

[0012] S2: Based on the optimized structural parameters and the indium tin oxide resistor film with a specific resistance value, a patterned indium tin oxide film is obtained by laser etching technology:

[0013] S3: A low surface resistance indium tin oxide film is placed on the bottom layer as a reflective layer, and a visible light transparent polymethyl methacrylate or polyvinyl chloride plate, a high resistivity indium tin oxide patterned film, a polymethyl methacrylate or polyvinyl chloride plate, and a low resistivity infrared emissivity indium tin oxide patterned film are placed thereon in sequence, and they are bonded together by transparent glue or resin;

[0014] S4: Hot pressing the multilayer structure to obtain a visible light transparent metamaterial absorber.

[0015] Furthermore, the polyethylene terephthalate film has a thickness of 0.175 mm, the indium tin oxide film has a thickness of 1.2 to 1.75 mm, and the polymethyl methacrylate or polyvinyl chloride plate has a thickness ranging from 1 mm to 3 mm.

[0016] Furthermore, the surface resistivity of the indium tin oxide film ranges from 6 to 300 Ω / sq.

[0017] Furthermore, the lamination hot pressing temperature ranges from 50 to 70° C., and the pressure ranges from 5 to 10 MPa.

[0018] Furthermore, the infrared emissivity indium tin oxide patterned film with low resistivity has a resistance of 6Ω / sq.

[0019] Furthermore, the thickness of the low-resistivity infrared emissivity indium tin oxide patterned film is 1 mm, and the thickness of the high-resistivity indium tin oxide patterned film is 1.5 mm.

[0020] Furthermore, the resistance of the high-resistivity indium tin oxide patterned film is 100Ω / sq, and the resistance of the high-resistivity indium tin oxide patterned film is 6Ω / sq.

[0021] Furthermore, the infrared stealth layer is a low-resistivity infrared emissivity indium tin oxide patterned film having structural units with gradient sizes or uniformly divided square structural units, and the infrared stealth layer is a low-resistivity infrared emissivity indium tin oxide patterned film having a gradient size structural unit duty ratio of 0.7, and the infrared stealth layer is a low-resistivity infrared emissivity indium tin oxide patterned film having a uniformly divided square structural unit duty ratio of 0.75.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] 1. The present invention proposes a method and device for preparing a visible light transparent metamaterial absorber. The existing methods and devices for preparing visible light transparent metamaterial absorbers have the problems of narrow absorption bandwidth, poor visible light transparency and difficulty in achieving infrared camouflage effect. The present invention comprises an infrared stealth layer, a first PMMA layer, a microwave absorption layer, a second PMMA layer and a microwave reflection layer. The visible light transparent properties of indium tin oxide film and polymethyl methacrylate or polyvinyl chloride plate are combined and arranged in a certain order to obtain a visible light transparent metamaterial absorber. Indium tin oxide with resistance loss is used as an absorbent. The resistance loss is increased while the electromagnetic resonance loss is introduced, which is beneficial to improving its absorption bandwidth and absorption intensity.

[0024] 2. The present invention makes full use of the adjustable resistance characteristics of indium tin oxide and the patternable characteristics of indium tin oxide film, and can achieve infrared dual stealth characteristics through structural optimization and filling ratio adjustment. By increasing the duty cycle of the high-conductivity indium tin oxide film in the infrared stealth layer, its infrared emissivity can be further reduced, thereby improving the infrared stealth characteristics;

[0025] 3. The present invention utilizes indium tin oxide thin film materials with different surface resistivities having optical transparency, utilizes laser etching technology to realize the designed pattern, and uses a high-duty-ratio highly conductive indium tin oxide thin film as a low infrared emission layer to realize a wide-band strong absorption absorber that is transparent to visible light and infrared camouflaged. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] FIG. 1( a ) is a structural diagram of a visible light transparent metamaterial absorber provided by the present invention;

[0027] FIG1( b ) is a structural unit diagram of a gradual size change of an infrared stealth layer provided by the present invention;

[0028] FIG1( c ) is a structural diagram of a microwave absorbing layer provided by the present invention;

[0029] Figure 2 is a rendering of embodiment 1 of the present invention;

[0030] Figure 3 is a rendering of Embodiment 2 of the present invention;

[0031] Figure 4 It is a front cross-sectional structural schematic diagram of the light-transparent metamaterial absorber device of the present invention.

[0032] In the figure: 1. infrared stealth layer; 2. first PMMA layer; 3. microwave absorption layer; 4. second PMMA layer; 5. microwave reflection layer. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] In order to further understand the content of the present invention, the present invention is described in detail in conjunction with the accompanying drawings.

[0035] As shown in FIGS. 1-4 , a method and device for preparing a visible light transparent metamaterial absorber include: an infrared stealth layer 1 , a first PMMA layer 2 , a microwave absorption layer 3 , a second PMMA layer 4 and a microwave reflection layer 5 .

[0036] The present invention will be further described below in conjunction with the embodiments.

[0037] As shown in Figure 1(a) and Figure 4As shown, the infrared stealth layer 1, the microwave absorption layer 3 and the microwave reflection layer 5 are indium tin oxide films of different resistivities prepared by magnetron sputtering on a polyethylene terephthalate film base. The infrared stealth layer 1 is used to reduce the infrared emissivity to achieve infrared stealth and work in conjunction with the microwave absorption layer. The microwave absorption layer 3 is used to absorb electromagnetic waves in the microwave frequency band. The microwave reflection layer 5 is used to reflect microwaves to cooperate with the microwave absorption layer 3 to adjust the wave absorption effect. At the same time, due to its material properties, it assists in achieving infrared stealth. The first PMMA layer 2 and the second PMMA layer 4 are both made of A plate-like component made of polymethyl methacrylate or polyvinyl chloride, the first PMMA layer 2 is used to separate the infrared stealth layer 1 and the microwave absorption layer 3, while ensuring the transmittance of visible light, the second PMMA layer 4 is used to separate the microwave absorption layer 3 and the microwave reflection layer 5, while also ensuring the transmittance of visible light, the infrared stealth layer 1 is a low-resistivity infrared emissivity indium tin oxide patterned film, the microwave absorption layer 3 is a high-resistivity indium tin oxide patterned film, the microwave reflection layer 5 is a low-resistance indium tin oxide film, which improves the infrared stealth characteristics.

[0038] A method for preparing a visible light transparent metamaterial absorber comprises the following steps:

[0039] Step 1: Using polyethylene terephthalate film as a substrate, indium tin oxide thin films with different resistivities are prepared by magnetron sputtering;

[0040] Step 2: Based on the optimized structural parameters and the specific resistance value of the indium tin oxide resistor film, a patterned indium tin oxide film is obtained by laser etching technology:

[0041] Step 3: Place a low surface resistance indium tin oxide film on the bottom layer as a reflective layer, and place a visible light transparent polymethyl methacrylate or polyvinyl chloride plate, a high resistivity indium tin oxide patterned film, a polymethyl methacrylate or polyvinyl chloride plate, and a low resistivity infrared emissivity indium tin oxide patterned film on it in sequence, and bond them together with transparent glue or resin;

[0042] Step 4: Hot-press the multilayer structure to obtain a visible light transparent metamaterial absorber.

[0043] The thickness of the polyethylene terephthalate film is 0.175 mm, the thickness of the indium tin oxide film is 1.2 to 1.75 mm, the thickness range of the polymethyl methacrylate or polyvinyl chloride plate is 1 mm to 3 mm, the surface resistivity range of the indium tin oxide film is 6 to 300 Ω / sq, the lamination hot pressing temperature range is 50 to 70°C, the pressure range is 5 to 10 MPa, the infrared emissivity indium tin oxide patterned film with low resistivity has a resistance of 6 Ω / sq, the infrared emissivity indium tin oxide patterned film with low resistivity has a thickness of 1 mm, the high resistivity indium tin oxide patterned film has a thickness of 1.5 mm, the resistance of the high resistivity indium tin oxide patterned film is 100 Ω / sq, and the resistance of the high resistivity indium tin oxide patterned film is 6 Ω / sq.

[0044] like Figure 2 As shown, the infrared stealth layer 1 is a low-resistivity infrared emissivity indium tin oxide patterned film with a size-gradient structural unit, and the infrared stealth layer 1 is a low-resistivity infrared emissivity indium tin oxide patterned film with a size-gradient structural unit with a duty cycle of 0.7. In the range of 7.3 to 39.5 GHz, the electromagnetic wave absorption rate of the metamaterial absorber can reach more than 90%, the infrared emissivity is 0.34, and the visible light transmittance reaches 55%;

[0045] like Figure 3 As shown, the infrared stealth layer 1 is a low-resistivity infrared emissivity indium tin oxide patterned film with uniformly divided square structural units. The infrared stealth layer 1 is a low-resistivity infrared emissivity indium tin oxide patterned film with uniformly divided square structural units. The duty cycle of the square structural units is 0.75. In the range of 7.3 to 35 GHz, the electromagnetic wave absorption rate of the metamaterial absorber can reach more than 90%, the infrared emissivity is 0.3, and the visible light transmittance reaches 53%.

[0046] Specifically, as shown in FIG1(a), first, from top to bottom, the patterned infrared stealth layer 1 is a low-resistivity infrared emissivity indium tin oxide patterned film, the first PMMA layer 2 is a 1 mm thick polymethyl methacrylate or polyvinyl chloride plate, the microwave absorption layer 3 is a high-resistivity microwave absorption layer indium tin oxide patterned film, the second PMMA layer 4 is a 1.5 mm thick polymethyl methacrylate or polyvinyl chloride plate, and the microwave reflection layer 5 is a low-resistance indium tin oxide film. The middle is coated with transparent glue, and at a temperature of 60° C. and a pressure of 5 MPa, the multilayer structure is finally hot-pressed to prepare a visible light transparent metamaterial absorber, wherein the visible light transparent metamaterial absorber has a thickness of 3 mm. Specifically, the infrared stealth layer 1 is a component made of a polyethylene terephthalate film with a thickness of 0.175 mm and an indium tin oxide film prepared by magnetron sputtering, and the surface resistance of the indium tin oxide film is 6Ω / sq and 100Ω / sq. Secondly, according to the structural parameters and the optimized design, An indium tin oxide resistor film with a specific resistance value is prepared by a laser etching process to obtain a pattern, wherein the infrared stealth layer 1 is a low-resistivity infrared emissivity indium tin oxide patterned film with a surface resistance of 6Ω / sq, and its pattern is shown in Figure 1(b). The infrared stealth layer 1 is a low-resistivity infrared emissivity indium tin oxide patterned film with a structural unit with a gradient size, and the infrared stealth layer 1 is a low-resistivity infrared emissivity indium tin oxide patterned film with a duty cycle of 0.7. The microwave absorption layer 3 is a high-resistivity indium tin oxide patterned film with a pattern as shown in Figure 1(c). The microwave absorption layer 3 is a high-resistivity indium tin oxide patterned film with a surface resistance of 100Ω / sq, and the microwave reflection layer 5 is a low-resistance indium tin oxide film with a resistance of 6Ω / sq. The thickness of the indium tin oxide film is 1.2-1.75mm, and the thickness of the polymethyl methacrylate or polyvinyl chloride board ranges from 1mm to 3mm, which is used to reflect microwaves to cooperate with the microwave absorption layer 3 to adjust the absorbing effect, and at the same time, its material properties assist in achieving infrared stealth.

[0047] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0048] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A visible light transparent metamaterial absorber device, characterized in that: include: Infrared stealth layer (1), first PMMA layer (2), microwave absorption layer (3), second PMMA layer (4) and microwave reflection layer (5); The infrared stealth layer (1), the microwave absorption layer (3) and the microwave reflection layer (5) are indium tin oxide thin films with different resistivities prepared by magnetron sputtering on a polyethylene terephthalate film base layer. The infrared stealth layer (1) is used to reduce the infrared emissivity to achieve infrared stealth and work in coordination with the microwave absorption layer. The microwave absorption layer (3) is used to absorb electromagnetic waves in the microwave frequency band. The microwave reflection layer (5) is used to reflect microwaves to cooperate with the microwave absorption layer (3) to adjust the wave absorption effect. At the same time, due to its material properties, it assists in achieving infrared stealth. The first PMMA layer (2) and the second PMMA layer (4) are both plate-shaped components made of polymethyl methacrylate or polyvinyl chloride. The first PMMA layer (2) is used to separate the infrared stealth layer (1) and the microwave absorption layer (3) while ensuring the transmittance of visible light. The second PMMA layer (4) is used to separate the microwave absorption layer (3) and the microwave reflection layer (5) while also ensuring the transmittance of visible light.

2. A visible light transparent metamaterial absorber device according to claim 1, characterized in that: The infrared stealth layer (1) is a low-resistivity infrared emissivity indium tin oxide patterned film, the microwave absorption layer (3) is a high-resistivity indium tin oxide patterned film, and the microwave reflection layer (5) is a low-resistance indium tin oxide film.

3. The method for preparing a visible light transparent metamaterial absorber according to claim 2, characterized in that: The steps include: S1: Using polyethylene terephthalate film as substrate, indium tin oxide thin films with different resistivities were prepared by magnetron sputtering; S2: Based on the optimized structural parameters and the indium tin oxide resistor film with a specific resistance value, a patterned indium tin oxide film is obtained by laser etching technology: S3: A low surface resistance indium tin oxide film is placed on the bottom layer as a reflective layer, and a visible light transparent polymethyl methacrylate or polyvinyl chloride plate, a high resistivity indium tin oxide patterned film, a polymethyl methacrylate or polyvinyl chloride plate, and a low resistivity infrared emissivity indium tin oxide patterned film are placed thereon in sequence, and they are bonded together by transparent glue or resin; S4: Hot pressing the multilayer structure to obtain a visible light transparent metamaterial absorber.

4. The method for preparing a visible light transparent metamaterial absorber according to claim 3, characterized in that: The polyethylene terephthalate film has a thickness of 0.175 mm, the indium tin oxide film has a thickness of 1.2 to 1.75 mm, and the polymethyl methacrylate or polyvinyl chloride plate has a thickness ranging from 1 mm to 3 mm.

5. The method for preparing a visible light transparent metamaterial absorber according to claim 3, characterized in that: The surface resistivity of the indium tin oxide film ranges from 6 to 300 Ω / sq.

6. The method for preparing a visible light transparent metamaterial absorber according to claim 3, characterized in that: The lamination hot pressing temperature ranges from 50 to 70° C., and the pressure ranges from 5 to 10 MPa.

7. The method for preparing a visible light transparent metamaterial absorber according to claim 3, characterized in that: The low resistivity infrared emissivity indium tin oxide patterned film has a resistance of 6Ω / sq.

8. The method for preparing a visible light transparent metamaterial absorber according to claim 3, characterized in that: The thickness of the low-resistivity infrared emissivity indium tin oxide patterned film is 1 mm, and the thickness of the high-resistivity indium tin oxide patterned film is 1.5 mm.

9. The method for preparing a visible light transparent metamaterial absorber according to claim 3, characterized in that: The resistance of the high-resistivity indium tin oxide patterned film is 100Ω / sq, and the resistance of the high-resistivity indium tin oxide patterned film is 6Ω / sq.

10. The method for preparing a visible light transparent metamaterial absorber according to claim 3, characterized in that: The low-resistivity infrared emissivity indium tin oxide patterned film has structural units with gradually varying sizes or uniformly divided square structural units. The duty ratio of the structural units with gradually varying sizes of the low-resistivity infrared emissivity indium tin oxide patterned film is 0.7, and the duty ratio of the uniformly divided square structural units of the low-resistivity infrared emissivity indium tin oxide patterned film is 0.75.

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