Infrared and radar compatible stealth vision window glass with sound and heat insulation function

Abstract

The application relates to an infrared and radar compatible invisible window glass with sound and heat insulation functions, which comprises outer glass and inner glass, a vacuum layer is arranged between the outer glass and the inner glass, an array of microwave frequency selection surface structures is arranged on the outer surface of the outer glass, an array of microwave resonance absorption structures is arranged on the inner surface of the outer glass, and an electromagnetic reflection film is arranged on the inner surface of the inner glass. The window glass integrates a transparent support structure and a compatible invisible function, can realize wide-spectrum and high-efficiency microwave absorption and low infrared emissivity based on itself, the microwave absorption range can cover 5-20 GHz, and the absorption efficiency is greater than 0.9. The infrared emissivity of the glass surface is as low as 0.23, the heat radiation amount of a target can be significantly reduced, and the probability of being detected can be reduced. In addition, the visible light transmittance of the window glass of the application is above 60%. Meanwhile, based on the vacuum insulation layer in the structure, the window glass of the application has sound insulation, noise reduction and heat insulation capabilities.

Description

Technical Field

[0001] This invention belongs to the field of wave-absorbing materials and relates to an infrared and radar-compatible stealth window glass with sound insulation and heat insulation functions. Background Technology

[0002] On today's battlefield, the diversification and intelligence of detection methods pose a severe challenge to the pre-battle survivability of weapons and equipment. Multi-band joint detection has become an inevitable trend in the development of modern military reconnaissance methods, with infrared and radar being the two most important target reconnaissance technologies. Therefore, developing materials that possess both radar stealth and infrared stealth capabilities will better meet practical needs and ultimately improve the camouflage and survivability of military targets when multiple detection methods are used in combination.

[0003] Most existing technologies utilize composite coatings to achieve stealth compatibility. However, composite coatings suffer from narrow microwave absorption bandwidth and low absorption efficiency, and their infrared stealth performance needs further improvement. Moreover, existing composite coatings are all non-transparent and cannot be applied to viewing windows.

[0004] In addition, Chinese patent CN112622391A discloses an optically transparent ultra-wideband radar and infrared dual stealth structure. To achieve high visible light transmittance, the overall structural design uses optically transparent conductive films and transparent dielectrics. From bottom to top, the structure consists of a backplate, a first intermediate dielectric layer, a first frequency selective surface layer, a second intermediate dielectric layer, and a second frequency selective surface layer. The first and second intermediate dielectric layers are made of high-transmittance polyethylene terephthalate (PET). The stealth structure mainly includes a low-emissivity infrared stealth layer composed of the second frequency selective surface layer and an ultra-wideband radar absorbing layer composed of the second frequency selective surface layer. However, this structure still has shortcomings in infrared and radar stealth capabilities, failing to meet higher requirements or other application scenarios, and also lacking sound and heat insulation functions. Summary of the Invention

[0005] The purpose of this invention is to solve the above-mentioned problems and provide an infrared and radar compatible stealth window glass with sound insulation and heat insulation functions, which has radar and infrared compatible stealth functions, while also having sound insulation and heat insulation capabilities.

[0006] To achieve the above objectives, the present invention provides an infrared and radar-compatible stealth window glass with sound insulation and heat insulation functions, comprising an outer glass layer and an inner glass layer, wherein a vacuum layer is provided between the outer glass layer and the inner glass layer, the outer surface of the outer glass layer is provided with a microwave frequency selective surface structure array, the inner surface of the outer glass layer is provided with a microwave resonant absorption structure array, and the inner surface of the inner glass layer is provided with an electromagnetic reflection film.

[0007] According to one aspect of the present invention, the microwave frequency selective surface structure array is a patterned structure array formed by depositing a first transparent conductive thin film material on the outer surface of the outer glass.

[0008] According to one aspect of the present invention, the transparent conductive film material is indium tin oxide or zinc aluminum oxide, with a sheet resistance of 8-15 Ω / sq and an infrared emissivity of less than 0.25.

[0009] According to one aspect of the present invention, the microwave resonant absorption structure array is a periodic pattern structure formed by depositing a second transparent conductive thin film material on the inner surface of the outer glass layer, the periodic pattern structure generating electromagnetic resonant absorption in the microwave band, absorbing microwaves of 5-20 GHz.

[0010] According to one aspect of the present invention, the second transparent conductive film material is indium tin oxide, zinc aluminum oxide, graphene, or silver nanowires, and its sheet resistance is 20-26 Ω / sq.

[0011] According to one aspect of the invention, the electromagnetic reflective film is a third transparent conductive film covering the inner surface of the inner glass layer, used to reflect microwave and infrared radiation.

[0012] According to one aspect of the present invention, the third transparent conductive film material is indium tin oxide, zinc aluminum oxide, graphene, or silver nanowires, and its sheet resistance is 8-15 Ω / sq.

[0013] According to one aspect of the present invention, the outer glass and the inner glass are any one of quartz glass, plexiglass, polyethylene, and polypropylene with high visible light transmittance, and have a dielectric constant of 2.45-3.8.

[0014] According to one aspect of the invention, the visible light transmittance of the infrared and radar compatible stealth window glass is higher than 60%.

[0015] This invention's viewing window integrates a transparent support structure with stealth functionality. It achieves broad-spectrum, high-efficiency microwave absorption and low infrared emissivity. The microwave absorption range covers 5-20 GHz with an absorption efficiency greater than 0.9. The infrared emissivity of the glass surface is as low as 0.23, significantly reducing the target's thermal radiation and thus lowering the probability of detection. Furthermore, the visible light transmittance of this invention's viewing window is above 60%.

[0016] The electromagnetic reflective film of the window glass of the present invention can efficiently reflect infrared radiation. The vacuum layer or air layer in the window structure can reduce heat transfer, prevent internal and external heat exchange, and play a certain role in heat insulation.

[0017] The medium / vacuum layer or air layer / medium layer in the window structure of the window glass of the present invention can effectively isolate the propagation of sound waves and achieve sound insulation and noise reduction.

[0018] The outer glass of the window in this invention can efficiently absorb external radar waves, while the inner glass can effectively attenuate or reflect electromagnetic radiation from electronic components inside the cockpit, thereby maximizing radar stealth. Attached Figure Description

[0019] Figure 1 A schematic diagram illustrating the structure of the viewing window glass according to the present invention;

[0020] Figure 2 A schematic diagram illustrating a microwave frequency selective surface structure array according to Embodiment 1 of the present invention;

[0021] Figure 3 A schematic diagram illustrating a microwave resonant absorption structure array according to Embodiment 1 of the present invention;

[0022] Figure 4 A schematic diagram illustrating a microwave frequency selective surface structure array according to Embodiment 2 of the present invention;

[0023] Figure 5 A schematic diagram illustrating a microwave resonant absorption structure array according to Embodiment 2 of the present invention;

[0024] Figure 6 A graph showing the optical transmittance of the window glass in Example 1;

[0025] Figure 7 Infrared performance diagram of the transparent conductive thin film material in Example 1;

[0026] Figure 8 This shows a visible light photograph and an infrared stealth performance diagram of the window glass in Example 1;

[0027] Figure 9 The diagram showing the microwave absorption measurement results under TE mode of the window glass in Example 1 is a multi-angle incident microwave absorption measurement result.

[0028] Figure 10 The graph shows the microwave absorption measurement results under TM mode of the window glass in Example 1, with microwaves incident from multiple angles.

[0029] Figure 11 This shows the simulation results of the thermal insulation performance of the window glass in Example 1;

[0030] Figure 12 This indicates the test results of the sound insulation performance of the window glass in Example 1;

[0031] Figure 13The diagram shows the microwave absorption results of the window glass in Example 2 under TE mode, with microwaves incident from multiple angles.

[0032] Figure 14 This diagram shows the microwave absorption results of the window glass in Example 2 under TM mode, with microwaves incident from multiple angles. Detailed Implementation

[0033] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly described below. Obviously, the drawings described below are merely some embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without creative effort.

[0034] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. The embodiments cannot be described in detail here, but the embodiments of the present invention are not limited to the following embodiments.

[0035] like Figure 1 As shown, the present invention provides an infrared and radar compatible stealth window glass with sound insulation and heat insulation functions, comprising an outer glass layer 1 and an inner glass layer 2, with a vacuum layer 3 provided between the outer glass layer 1 and the inner glass layer 2, a microwave frequency selective surface structure array 11 provided on the outer surface of the outer glass layer 1, a microwave resonant absorption structure array 12 provided on the inner surface of the outer glass layer 1, and an electromagnetic reflection film 13 provided on the inner surface of the inner glass layer 2.

[0036] In this invention, the microwave frequency selective surface structure array 11 is a patterned structure array formed by depositing a first transparent conductive thin film material on the outer surface of the outer glass 1. The patterned structure is a periodic array of a specific shape, which can be a regular or irregular structure such as square, circle, or rectangle. This structure array has selective microwave transmittance, enabling high transmittance in the 5-20 GHz frequency band. According to one embodiment of the invention, the period of the patterned structure array is 0.5 mm, and the patterned structure is square. The first transparent conductive thin film material is indium tin oxide or zinc aluminum oxide, with a sheet resistance of 8-15 Ω / sq and a thickness of 200-250 nm. This conductive film has high conductivity, thereby ensuring that the infrared emissivity of the window surface is less than 0.25.

[0037] The microwave resonant absorption structure array 12 of this invention is a periodic pattern structure formed by depositing a second transparent conductive thin film material on the inner surface of the outer glass layer 1. The periodic pattern can be a regular or irregular structure such as square, rectangular, or open-loop. The periodic structure can localize electromagnetic waves within the conductive periodic structure, generating resonant absorption of microwaves in the 5-20 GHz range. The second transparent conductive thin film material is indium tin oxide or zinc aluminum oxide, with a sheet resistance of 20-26 Ω / sq and a thickness of 150-200 nm. This sheet resistance conductive film, combined with the designed microwave resonant absorption structure, can achieve broadband microwave absorption.

[0038] The electromagnetic reflective film 13 of this invention is a complete third transparent conductive film deposited on the inner surface of the inner glass layer 2, used to reflect microwaves and infrared radiation. The material of the third transparent conductive film is indium tin oxide or zinc aluminum oxide, with a sheet resistance of 8-15 Ω / sq and a thickness of 200-250 nm. Conductive films with these parameters can efficiently reflect microwaves and improve the ability of microwave resonant structures to dissipate microwaves.

[0039] The viewing glass of the present invention has an outer glass 1 and an inner glass 2, which are any one of quartz glass, plexiglass, polyethylene, and polypropylene with high visible light transmittance, and a dielectric constant of 2.45-3.8.

[0040] According to one embodiment of the present invention, the outer glass layer 1 has a thickness of 2.6-3 mm and a dielectric constant of 2.45-3.8. The vacuum layer 3 has a thickness of 2.2-2.6 mm.

[0041] This invention's viewing window integrates a transparent support structure with stealth functionality. It achieves broad-spectrum, high-efficiency microwave absorption and low infrared emissivity. The microwave absorption range covers 5-20 GHz with an absorption efficiency greater than 0.9. The infrared emissivity of the glass surface is as low as 0.23, significantly reducing the target's thermal radiation and thus lowering the probability of detection. Furthermore, the visible light transmittance of this invention's viewing window is above 60%.

[0042] The electromagnetic reflective film 13 of the window glass of the present invention can efficiently reflect infrared radiation, and the vacuum layer 3 in the window structure can reduce heat transfer, thus preventing heat exchange between the inside and outside of the window and playing a certain role in heat insulation. At the same time, with the vacuum layer, the conduction of internal heat to the surface of the window glass can be effectively reduced, further reducing the surface temperature of the window.

[0043] The vacuum layer in the window glass structure of the present invention can achieve sound insulation and noise reduction functions.

[0044] The outer glass 1 of the window glass of this invention can achieve efficient absorption of external radar waves, and the inner glass 2 can effectively attenuate or reflect the electromagnetic wave radiation of electronic components inside the cockpit, thereby maximizing radar stealth.

[0045] The following two embodiments illustrate the window glass of the present invention in detail.

[0046] Example 1

[0047] Combination Figure 1 As shown, in this embodiment, the outer glass layer 1 and the inner glass layer 2 are made of quartz glass, both with a dielectric constant of 3.75. The outer glass layer 1 has a thickness of 3 mm, the inner glass layer 2 has a thickness of 1.5 mm, and the vacuum layer has a thickness of 2.7 mm. The microwave frequency-selective surface structure array 11 and the microwave resonant structure array are fabricated on the outer and inner surfaces of the outer glass layer 1 using photolithography and wet etching processes, respectively. Figure 6 As shown, the average visible light transmittance of the window ratio in this embodiment is higher than 60%.

[0048] In this embodiment, the microwave frequency selective surface structure array is configured as follows: Figure 2 As shown, the structure is a block array. The structural parameters are g1 = 0.1 and w = 0.45. This array structure ensures a microwave transmittance greater than 98% in the 5-20 GHz range. Indium tin oxide (ITO) is chosen as the transparent thin film material, with a sheet resistance of 8 Ω / sq and a film thickness of 200 nm. Its infrared emissivity was measured using an infrared camera (model PI640Optris Inc) with a spectral range of 7.5-13 μm, and the measured value was 0.1. The infrared spectral measurement results are as follows: Figure 7 As shown. The absorptivity calculated based on transmittance and reflectance is 0.1, which is consistent with the measured emissivity. The theoretically calculated infrared emissivity of the outer glass surface is 0.234. The measured surface emissivity of the outer glass surface is 0.24, and the experimental value matches the calculated value. Its infrared stealth effect is as follows. Figure 8 As shown.

[0049] In this embodiment, the microwave resonant absorption structure array 12 is configured as follows: Figure 3 As shown, its array period is 5mm, the second transparent conductive film material is indium tin oxide (ITO), its sheet resistance is 22.5Ω / sq, the film thickness is 200nm, l1=4.2mm, l2=4.7mm, l3=2.4mm, w1=1mm, w2=0.9mm. Figure 9 and Figure 10 The figures show the measured microwave absorptivity for vertically polarized (TE) and horizontally polarized (TM) microwaves as the incident angle varies from 8 degrees to 45 degrees. As can be seen from the attached figures, the absorption efficiency for vertical incidence is greater than 90% in the 5-20 GHz range, and the absorption efficiency for oblique incidence within 30 degrees is greater than 80%.

[0050] In this embodiment, the vacuum layer in the structure provides the window glass with heat insulation and sound insulation functions, wherein the heat insulation performance is... Figure 11 The temperature of the bottom surface of the inner glass layer 2 varies from 300K to 400K. The temperature of the outer surface of the outer glass layer 1 is shown by solid and dashed lines, respectively, for cases with and without a vacuum layer. With a vacuum layer, the surface temperature of the window glass can be effectively reduced. The sound insulation and noise reduction experimental results are as follows: Figure 12 As can be seen, the glass / vacuum layer / glass structure system can effectively achieve sound insulation and noise reduction, with noise reduction ranging from 40dB to 80dB.

[0051] Example 2

[0052] Combination Figure 1 As shown, in this embodiment, the outer glass 1 and the inner glass 2 are made of plexiglass, both with a dielectric constant of 2.45. The outer glass 1 has a thickness of 2.8 mm, the inner glass 2 has a thickness of 1.5 mm, and the vacuum layer has a thickness of 2.6 mm. The microwave frequency-selective surface structure array 11 and the microwave resonant structure array are fabricated on the outer and inner surfaces of the outer glass 1, respectively, by laser etching.

[0053] In this embodiment, the microwave frequency selective surface structure array is configured as follows: Figure 4 As shown, the structure is a regular hexagonal array. The structural parameters are g2 = 0.008 and d = 0.2. This array structure ensures a microwave transmittance greater than 98% in the 5-20 GHz range. The transparent thin film material is indium tin oxide (ITO), with a sheet resistance of 8 Ω / sq and a film thickness of 200 nm. Its infrared emissivity is 0.1.

[0054] In this embodiment, the microwave resonant absorption structure array 12 is configured as follows: Figure 5 As shown, its array period is 5mm, the second transparent conductive film material is indium tin oxide (ITO), its sheet resistance is 22.5Ω / sq, the film thickness is 200nm, l4=4.6mm, l0=4.9mm, w4=1mm, w5=1.2mm. Figure 13 and Figure 14 The figures show the measured microwave absorptivity for vertically polarized (TE) and horizontally polarized (TM) microwaves as the incident angle varies from 8 degrees to 45 degrees. As can be seen from the attached figures, the absorption efficiency for vertical incidence is greater than 93% in the 5-20 GHz range, and the absorption efficiency for oblique incidence within 30 degrees is greater than 90%.

[0055] The above description is merely one embodiment of the present invention and is not intended to limit the invention. Those skilled in the art will recognize that the present invention can be modified and varied in various ways. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An infrared and radar-compatible stealth window glass with sound and heat insulation functions, characterized in that, It includes an outer glass layer (1) and an inner glass layer (2), with a vacuum layer (3) between the outer glass layer (1) and the inner glass layer (2). The outer surface of the outer glass layer (1) is provided with a microwave frequency selective surface structure array (11), the inner surface of the outer glass layer (1) is provided with a microwave resonant absorption structure array (12), and the inner surface of the inner glass layer (2) is provided with an electromagnetic reflection film (13). The electromagnetic reflection film (13) is a third transparent conductive film covering the inner surface of the inner glass layer (2) and is used to reflect microwave and infrared radiation. The microwave resonant absorption structure array (12) is a periodic pattern structure formed by depositing a second transparent conductive film material on the inner surface of the outer glass (1). The periodic pattern structure generates electromagnetic resonance absorption in the microwave band, absorbing microwaves of 5-20 GHz. The sheet resistance of the second transparent conductive film material is 20-26 Ω / sq. The periodic pattern structure of the microwave resonant absorption structure array (12) is a regular or irregular structure. The microwave frequency selective surface structure array (11) is a patterned structure array formed by depositing a first transparent conductive thin film material on the outer surface of the outer glass (1); The first transparent conductive film material is indium tin oxide or zinc aluminum oxide, with a sheet resistance of 8-15 Ω / sq and an infrared emissivity of less than 0.

25.

2. The infrared and radar-compatible stealth window glass with sound and heat insulation functions according to claim 1, characterized in that, The second transparent conductive film material is indium tin oxide, zinc aluminum oxide, graphene, or silver nanowires.

3. The infrared and radar-compatible stealth window glass with sound and heat insulation functions according to claim 1, characterized in that, The material of the third transparent conductive film is indium tin oxide, zinc aluminum oxide, graphene, or silver nanowires, and its sheet resistance is 8-15 Ω / sq.

4. The infrared and radar-compatible stealth window glass with sound and heat insulation functions according to claim 1, characterized in that, The outer glass (1) and inner glass (2) are any one of quartz glass, plexiglass, polyethylene, and polypropylene with high visible light transmittance, and the dielectric constant is 2.45-3.

8.

5. The infrared and radar-compatible stealth window glass with sound and heat insulation functions according to claim 1, characterized in that, The infrared and radar-compatible stealth window glass has a visible light transmittance of over 60%.

6. The infrared and radar-compatible stealth window glass with sound and heat insulation functions according to claim 1, characterized in that, The vacuum layer (3) reduces the heat conduction of the window glass, giving it heat insulation capabilities.

7. The infrared and radar-compatible stealth window glass with sound and heat insulation functions according to claim 1, characterized in that, The vacuum layer (3) gives it sound insulation and noise reduction capabilities.

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