High-transmittance microwave absorption peak frequency adjustable light window based on thermal phase change material

Abstract

The high-transparency microwave absorption peak frequency adjustable light window based on a thermal phase change material belongs to the field of optical transparent electromagnetic shielding and microwave absorption. The high-transparency microwave absorption light window is composed of a transparent medium layer A, a thermal phase change material mesh layer, a transparent medium layer B and a transparent microwave shielding layer, and the thermal phase change material mesh layer and the transparent microwave shielding layer are respectively placed in parallel on the two sides of the transparent medium layer B. Under the premise of high optical transparency, the absorption of the light window is caused by the resonance of two Fabry-Perot cavities, and by controlling the temperature, the absorption peak frequency is converted from being dominated by one Fabry-Perot cavity to being dominated by the other Fabry-Perot cavity, so that the continuous adjustment of the absorption peak frequency is realized. The application of vanadium dioxide in the field of adjustable peak frequency is expanded, and the application has the advantages of simple structure, adjustable absorption peak frequency, wide application range and the like.

Description

Technical Field

[0001] This invention belongs to the field of optically transparent electromagnetic shielding and microwave absorption, and specifically relates to a high-transmittance microwave absorption peak frequency adjustable optical window based on thermally induced phase change materials. Background Technology

[0002] In recent years, electromagnetic wave applications have permeated all aspects of life, from military defense and national defense to daily production and daily life, encompassing radar detection, electronic reconnaissance, satellite communication, mobile phone communication, electromagnetic flaw detection, and medical diagnosis. With the continuous development of electromagnetic wave applications, space is now filled with electromagnetic wave signals of various frequencies. Since the 1970s, due to the rapid development of microwave semiconductor circuits, microwaves have occupied an increasingly important position in the field of radio communication technology. While the widespread application of microwaves brings convenience to people's lives, the side effects, including harm to human health and electromagnetic interference to electronic equipment leading to system failures, are increasingly attracting attention, leading to the rise of electromagnetic shielding technology.

[0003] Electromagnetic shielding is mainly achieved through two methods: electromagnetic reflection and electromagnetic absorption. Among these, the absorption-type electromagnetic shielding method used by microwave absorbers is a relatively ideal method because no electromagnetic waves are reflected back into space, and it has significant application value, especially in the radar stealth of military equipment. However, microwave absorbers based on traditional materials passively absorb microwaves, resulting in fixed absorption characteristics and a lack of adaptability and tunability, making it difficult to meet practical needs. Therefore, how to control the absorption characteristics has become a research focus, especially the control of the absorption peak frequency, which has become a recent research hotspot in radar communication systems and controllable stealth camouflage systems.

[0004] Currently, a key challenge and hot topic in microwave tunable absorption is its application in situations requiring optical transparency, such as optical windows in aircraft / satellites / ships / automobiles, optical instrument windows and display panels, electromagnetic isolation rooms and security facility windows, transparent components in communication equipment, and mobile phone touchscreens. Developing materials and devices with tunable peak absorption frequencies and high transmittance in these fields holds immense promise for future applications.

[0005] Phase change materials exhibit reversible changes in electromagnetic properties when driven by external excitation. Among them, phase change materials have attracted considerable attention due to their phase change temperature being close to room temperature and their theoretical conductivity having an adjustable range of nearly five orders of magnitude. Patents 202110465365.1, 202110497432.8, 202010331974.3, 202011261049.4, 202022308742.4, 201821278319.0, 201821438858.6, 201821446265.4, 201821907011.8, 201920654141.3, 201921357422.9, 201921357423.3, and 201921831563.X are all vanadium dioxide-based microwave absorbers. However, if these absorbers are to be applied in the field of optically transparent microwave absorption, they mainly operate in the THz band. This is because phase change materials exhibit electromagnetic inertia in both the THz and microwave bands. Due to significant differences in properties, the absorption characteristics of these THz absorbers change in the microwave band, making them unsuitable for microwave applications. Furthermore, these absorbers are typically built on a metal reflective layer, and the large occupancy of the vanadium dioxide pattern results in opacity or poor transparency in the optical band, rendering them unsuitable for optically transparent applications. In addition, existing absorbers are primarily based on ideal phase change materials, with the ideal conductivity after phase change approximating that of metals. However, in reality, the conductivity after phase change is far lower than that of metals. Moreover, the theoretical limit for conductivity change in phase change materials is five orders of magnitude, but in practical applications, due to various factors, it is difficult to achieve a conductivity change of five orders of magnitude. These factors lead to the poor performance of existing absorbers designed according to theoretical conditions in practical applications.

[0006] While patents 202011136561.6 and 202011121522.9 can achieve tunable and microwave absorption effects under the premise of optical transparency, the main reason for the absorption is due to graphene rather than phase change materials. Furthermore, the tunable characteristics of patent 202011121522.9 primarily target transmission characteristics rather than absorption characteristics. Although patent 202210110004.X can achieve tunable microwave absorption characteristics using thermally induced phase change materials under the premise of optical transparency, it cannot achieve tunable absorption peak frequency.

[0007] In summary, existing microwave absorption technologies based on phase change materials cannot simultaneously achieve optical transparency and adjustable absorption peak frequency. Summary of the Invention

[0008] The purpose of this invention is to overcome the shortcomings of existing technologies and other solutions by developing a high-transmittance microwave absorption peak frequency adjustable optical window based on thermally induced phase change materials. This allows for adjustment of the absorption peak frequency while maintaining high optical transparency. This not only makes it more suitable for practical applications but also expands the application of phase change materials in the microwave band.

[0009] The technical solution adopted in this invention is as follows: the optical window comprises, from top to bottom, a transparent dielectric layer A, a thermally induced phase change material grating layer, a transparent dielectric layer B, and a transparent microwave shielding layer; the thermally induced phase change material grating layer refers to a grating-like microstructure composed of thermally induced phase change material grating units arranged on the upper surface of the transparent dielectric layer B; the thermally induced phase change material refers to a material whose conductivity can be reversibly and continuously changed under temperature-driven conditions; the absorption peak frequency refers to the frequency at which the optical window achieves maximum absorption; the absorption of the high-transmittance microwave absorption peak frequency adjustable optical window is caused by the resonance of two Fabry-Perot cavities, the first Fabry-Perot cavity being from the upper surface of the transparent dielectric layer A to the upper surface of the transparent microwave shielding layer, and the second Fabry-Perot cavity being... The upper surface of the dielectric layer A extends to the upper surface of the thermally induced phase change material (TIC) grating layer. The two Fabry-Perot cavities have different optical thicknesses, resulting in different absorption peak frequencies. At temperature T1, the conductivity of the TIC grating layer is poor, and the first Fabry-Perot cavity dominates the light window. At temperature T2, the conductivity of the TIC grating layer increases, and the second Fabry-Perot cavity dominates the light window. Within the temperature range T1 to T2 (T1 < T2), as the temperature increases, the light window shifts from being dominated by the first Fabry-Perot cavity to being dominated by the second Fabry-Perot cavity, thus achieving adjustable absorption peak frequency.

[0010] As a preferred basic structure, the above-mentioned high-transmittance microwave absorption peak frequency adjustable light window based on thermally induced phase change material has one or more antireflective films A and one or more protective layers A arranged in parallel on the upper side of the transparent dielectric layer A; and one or more antireflective films B and one or more protective layers B arranged in parallel on the lower side of the transparent microwave shielding layer.

[0011] As a preferred basic structure, in the above-mentioned high-transmittance microwave absorption peak frequency adjustable light window based on thermally induced phase change material, the thickness of the transparent dielectric layer B is greater than half the thickness of the transparent dielectric layer A.

[0012] As a preferred basic structure, the above-mentioned high-transmittance microwave absorption peak frequency adjustable optical window based on thermally induced phase change materials includes vanadium oxide, vanadium dioxide, vanadium pentoxide, vanadium-doped vanadium dioxide, tungsten-doped vanadium dioxide, and magnesium-doped vanadium dioxide.

[0013] As a preferred basic structure, the above-mentioned high-transmittance microwave absorption peak frequency adjustable light window based on thermally induced phase change material has the following shapes for the thermally induced phase change material grid unit: square grid, circular ring grid, triangular distributed circular ring and sub-circular ring array grid, metal grid based on randomly distributed circular ring, and metal grid based on multi-period nested array of metal circular rings.

[0014] As a preferred basic structure, the above-mentioned high-transmittance microwave absorption peak frequency adjustable light window based on thermally induced phase change material has a material thickness of more than 50 nm in the thermally induced phase change material grid layer.

[0015] As a preferred basic structure, the above-mentioned high-transmittance microwave absorption peak frequency adjustable light window based on thermally induced phase change material can have transparent dielectric layer A and transparent dielectric layer B made of any transparent material, which can be used as a transparent light window material that meets the requirements of the application.

[0016] As a preferred basic structure, the above-mentioned high-transmittance microwave absorption peak frequency adjustable light window based on thermally induced phase change material can have any transparent microwave shielding material as the transparent material that meets the requirements of the application and has microwave shielding capability.

[0017] The innovativeness and good effects of this invention are:

[0018] 1. This invention proposes a high-transmittance microwave absorption peak frequency tunable optical window composed of a transparent dielectric layer A, a thermally induced phase change material grating layer, a transparent dielectric layer B, and a transparent microwave shielding layer. In the microwave band, the absorption mechanism of this optical window is as follows: Electromagnetic waves incident on the upper surface of the transparent dielectric layer A directly reflect electromagnetic wave 1; the transparent dielectric layer A and the transparent microwave shielding layer form a first Fabry-Perot cavity, from which electromagnetic waves 2 are reflected multiple times; the upper surface of the transparent dielectric layer A and the upper surface of the thermally induced phase change material grating layer form a second Fabry-Perot cavity, from which electromagnetic waves 3 are reflected multiple times. Because the two Fabry-Perot cavities have different optical thicknesses, the electromagnetic waves reflected multiple times by the two cavities have different phase differences. Electromagnetic waves 1, 2, and 3 have different amplitudes, periods, and phases, and therefore undergo vector superposition at the incident surface (the upper surface of the transparent dielectric layer A). Some frequencies of electromagnetic waves exhibit destructive interference. The main frequency band of the interference destructive interference depends primarily on the proportion of the two Fabry-Perot cavities to the overall optical window and the optical thickness of the two Fabry-Perot cavities. By utilizing the resistive characteristics of the thermally induced phase change material in microwaves, electromagnetic waves are dissipated, thereby achieving microwave absorption characteristics.

[0019] 2. Based on innovation point 1, this invention mainly consists of two Fabry-Perot cavities. The first Fabry-Perot cavity extends from the upper surface of the transparent dielectric layer A to the upper surface of the transparent microwave shielding layer, and the second Fabry-Perot cavity extends from the upper surface of the transparent dielectric layer A to the upper surface of the thermally induced phase change material grid layer. Due to the different optical thicknesses of the two Fabry-Perot cavities, the absorption peak frequencies are different. The optical thickness of the first Fabry-Perot cavity is greater than that of the second Fabry-Perot cavity, and the absorption peak frequency caused by the first Fabry-Perot cavity is less than that caused by the second Fabry-Perot cavity. At temperature T1, the conductivity of the thermally induced phase change material (TIC) grating layer is poor, resulting in minimal loss of electromagnetic waves passing through it. Therefore, the optical window is primarily dominated by the first Fabry-Perot cavity. As the temperature gradually increases to T2, the conductivity of the TIC grating layer gradually increases, the reflection coefficient of the first Fabry-Perot cavity gradually decreases, while the reflection coefficient of the second Fabry-Perot cavity gradually increases. Thus, the overall reflection coefficient of the optical window gradually shifts from being dominated by the first Fabry-Perot cavity to being dominated by the second. Because the optical window has a transparent microwave shielding layer, transmission is almost negligible; the lower the reflection, the greater the absorption. Therefore, the absorption peak frequency of the optical window gradually shifts from being dominated by the first Fabry-Perot cavity to being dominated by the second. This shift of the absorption peak frequency towards higher frequencies allows for adjustable absorption peak frequency. This differs from currently known absorbers and frequency-selective surface tuning methods. Most known tuning methods involve changing the conductivity to alter the equivalent shape of the structure, resulting in poor tuning continuity, complex structures that make the fabrication process based on secondary exposure difficult and lengthy. In contrast, this invention utilizes a dual Fabry-Perot cavity combined with a thermally induced phase change material grid layer with tunable conductivity to achieve continuous frequency tuning with a simple structure.

[0020] 3. The high-transmittance microwave absorption peak frequency adjustable optical window proposed in this invention employs a grid-like microstructure in the thermally induced phase change material grid layer. This not only allows for good light transmission by designing different porosity ratios, but also ensures reliable electrical connection of the thermally induced phase change material grid layer as its conductivity increases. Traditional phase change material absorbers often use patch patterns, which lack reliable electrical connections between patterns. However, the adjustable absorption peak frequency of the high-transmittance microwave absorption peak frequency optical window proposed in this invention depends on the thermally induced phase change material grid layer providing different conductivities, thereby affecting the proportion of reflection of the two Fabry-Perot cavities into the overall optical window. Therefore, traditional patch patterns cannot achieve this.

[0021] 4. In practical applications, due to various factors, the conductivity of phase change materials (PCMs) cannot achieve a change of five orders of magnitude, and the conductivity after phase change is lower than that of metals. This results in poor performance of many current absorbers in practical applications. This invention considers the changes in the conductivity of PCMs during practical use and the actual conductivity after phase change. The required change in sheet resistance of the PCM film is small, and the required sheet resistance after phase change is also large, making it easy to fabricate in practice. Therefore, this invention can also achieve good absorption peak frequency adjustment in practical applications.

[0022] 5. The microwave absorption peak frequency adjustable optical window of the present invention uses a thermally induced phase change material grid layer. By designing the porosity, it can have a low light transmission loss. It forms a stacked structure with two transparent dielectric layers and a transparent microwave shielding layer. Since each unit has good optical transparency and the light wave only passes through the stacked structure once, the microwave absorption peak frequency adjustable optical window has high optical transparency.

[0023] In summary, this invention, while maintaining high optical transparency, allows for continuous adjustment of the absorption peak frequency of the optical window by controlling its temperature. It is a high-transmittance microwave absorption peak frequency adjustable optical window based on thermally induced phase change materials. This invention considers the practical characteristics of thermally induced phase change materials, thus possessing strong practicality. Furthermore, it solves the problem that existing microwave absorption technologies based on phase change materials struggle to simultaneously achieve optical transparency and adjustable absorption peak frequency. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a schematic cross-sectional view of a preferred structure of a high-transmittance microwave absorption peak frequency adjustable light window based on thermally induced phase change materials.

[0026] Figure 2 It is an array diagram of the thermally induced phase change material grid unit using a periodic arrangement (5×3) of circular ring grids.

[0027] Figure 3 These are schematic diagrams showing the shapes of grid units for different thermally induced phase change materials.

[0028] Figure 4 This is a structural schematic diagram of an embodiment.

[0029] Figure 5 These are the theoretical calculation results of the absorption rate under different sheet resistance conditions of the thin films in the examples.

[0030] Part numbers in the diagram are explained as follows: 1. Protective layer A; 2. Antireflective layer A; 3. Transparent dielectric layer A; 4. Adhesive layer A; 5. Thermochromic phase change material grid layer; 6. Transparent dielectric layer B; 7. Adhesive layer B; 8. Transparent microwave shielding layer; 9. Antireflective layer B; 10. Protective layer B; 11. Thermochromic phase change material grid unit; 12. Quartz glass; 13. Vanadium dioxide; 14. Quartz glass; 15. Transparent ITO backplate. Detailed Implementation

[0031] The present invention will be further described below with reference to the accompanying drawings and preferred embodiments: The object of the present invention is achieved as follows: The optical window includes, from top to bottom, a transparent dielectric layer A3, a thermally induced phase change material grating layer 5, a transparent dielectric layer B6, and a transparent microwave shielding layer 8; the thermally induced phase change material grating layer 5 refers to a grating-like microstructure formed by thermally induced phase change material grating units 11 arranged on the upper surface of the transparent dielectric layer B6; the thermally induced phase change material refers to a material whose conductivity can be reversibly and continuously changed under temperature drive; the absorption peak frequency refers to the frequency at which the optical window achieves maximum absorption rate; the absorption of the high-transmittance microwave absorption peak frequency adjustable optical window is caused by the resonance of two Fabry-Perot cavities, the first Fabry-Perot cavity being from the upper surface of the transparent dielectric layer A3 to the upper surface of the transparent microwave shielding layer 8, and the second Fabry-Perot cavity being from the upper surface of the transparent dielectric layer A3 to the upper surface of the transparent microwave shielding layer 8. The upper surface of layer 3 extends to the upper surface of the thermally induced phase change material grating layer 5; the two Fabry-Perot cavities have different optical thicknesses, resulting in different absorption peak frequencies; at temperature T1, the conductivity of the thermally induced phase change material grating layer 5 is poor, and the first Fabry-Perot cavity dominates the optical window; at temperature T2, the conductivity of the thermally induced phase change material grating layer 5 increases, and the second Fabry-Perot cavity dominates the optical window; within the temperature range from T1 to T2, where T1 < T2, as the temperature increases, the optical window shifts from being dominated by the first Fabry-Perot cavity to being dominated by the second Fabry-Perot cavity, thus achieving adjustable absorption peak frequency.

[0032] Figure 1This is a cross-sectional schematic diagram of a preferred structure for a high-transmittance microwave absorption peak frequency adjustable light window based on thermochromic phase change materials. The transparent dielectric layer A3 and transparent dielectric layer B6 can be any transparent material, as long as they can serve as transparent light window materials that meet the requirements of the application. At the same time, the thermochromic phase change material grid layer 5 and the transparent microwave shielding layer 8 can be processed onto the surface of the transparent dielectric layer B6 according to a certain process, including ordinary glass, quartz glass, infrared materials, and transparent resin materials. The adhesive layer A4 helps to connect the transparent dielectric layer A3 and the thermochromic phase change material grid layer 5. The adhesive layer B7 helps to fix the transparent microwave shielding layer 8 to the underside of the transparent dielectric layer 6. Single or multiple antireflective films (2 and 9) enhance the light transmittance of the light window. Single or multiple protective layers (1 and 10) are used to protect the transparent dielectric layer A3 and the transparent microwave shielding layer 8 to prevent scratches or long-term exposure to air, which would cause corrosion and oxidation and avoid affecting the electromagnetic transmission performance and light transmittance performance of the transparent microwave shielding layer 8. In practical applications, the transparent dielectric layer A 3, the thermally induced phase change material grid layer 5, the transparent dielectric layer B 6, and the transparent microwave shielding layer 8 are indispensable elements of this invention. Depending on the process and the actual application, the adhesive layer (4 and 7), the antireflective film (2 and 9), and the protective layer (1 and 10) may or may not be present.

[0033] Figure 2 The present invention illustrates a periodic array (5×3) of the thermally induced phase change material grid unit using a circular ring grid. Taking the thermally induced phase change material grid unit as an example, it is arranged in a two-dimensional orthogonal array to form a periodic array.

[0034] Figure 3 The diagram shows the shapes of grid units for different thermally induced phase change materials: (a) is a square grid, (b) is a circular ring grid, (c) is a triangularly distributed circular ring and sub-circular ring array grid, (d) is a metal grid based on randomly distributed circular rings, and (e) is a multi-period metal ring nested array grid.

[0035] To facilitate understanding of the present invention, the invention will be described more clearly and completely below in conjunction with the accompanying drawings and embodiments, but the scope of protection of the present invention is not limited to the following specific embodiments.

[0036] A schematic diagram of the structure according to an embodiment of the present invention is shown below. Figure 4As shown, the structure consists of a first layer of transparent quartz glass, a second layer of thermally induced phase change material (TIC) mesh, a third layer of transparent quartz glass, and a fourth layer of transparent ITO backsheet. In this example, the TIC mesh is a square grid with a duty cycle of 5%. The TIC material is vanadium dioxide, and the simulated sheet resistance variation at different temperatures ranges from 20 Ω / sq to 3 Ω / sq. The transparent microwave shielding layer 8 is an ITO film with 96% light transmittance and a sheet resistance of 6 Ω / sq. Both the ITO and vanadium dioxide layers are 200 nm thick. The first layer of transparent quartz glass has a thickness of 1.8 mm, and the second layer has a thickness of 1.5 mm.

[0037] Since transmittance is one of the key parameters of a high-transmittance microwave absorption peak frequency tunable light window, the transmittance of the sample in the embodiment was analyzed. The transmittance of the thermally induced phase change material grid layer 5 is 95%; the visible light transmittance of the ITO film used in the transparent microwave shielding layer 8 is about 96%, so the normalized visible light transmittance of the overall structure is about 91.2%. It is still suitable for applications with high transparency requirements.

[0038] The effects of this invention can be achieved through Figure 5 Further explanation:

[0039] Since the sheet resistance of phase change materials is correlated with temperature, decreasing as temperature increases, the sheet resistance of the vanadium dioxide used in this embodiment can vary from 20 Ω / sq to 3 Ω / sq with temperature. In theoretical calculations, the simulated sheet resistance variation range of vanadium dioxide is 20 Ω / sq-3 Ω / sq. The variation in absorption performance of the high-transmittance microwave absorption peak frequency adjustable optical window based on the thermally induced phase change material is as follows... Figure 5 As shown in the figure, the black dashed line represents the contour line indicating an absorption rate of 90%. It can be seen that when the sheet resistance of vanadium dioxide is 20 Ω / sq, the amplitude of the highest absorption peak of the optical window has not yet reached 90%. As the sheet resistance of vanadium dioxide decreases to 7.9 Ω / sq, the optical window achieves an absorption rate greater than 99.98% at 13.39 GHz. When the sheet resistance of vanadium dioxide is further reduced to 7 Ω / sq, 6 Ω / sq, and 5 Ω / sq, the peak absorption of the optical window is 99.94%, 99.7%, and 99.86%, respectively, with peak absorption frequencies of 13.99 GHz, 15.22 GHz, and 17.41 GHz. When the sheet resistance of vanadium dioxide is 4 Ω / sq, the peak absorption frequency of the optical window shifts to 18 GHz, achieving a peak absorption rate of 99.98%.

[0040] In summary, this embodiment, under high light transmittance, reduces the sheet resistance of vanadium dioxide from 20 Ω / sq to 3 Ω / sq by controlling the temperature, and the absorption peak frequency of the optical window can be shifted from 13.39 GHz to 18 GHz; thus, the absorption peak frequency is continuously adjustable with a large adjustment range.

[0041] The above description is merely a specific example of the present invention. Obviously, those skilled in the art, after understanding the content and principles of the present invention, may make various modifications and changes in form and detail without departing from the principles and structure of the present invention. However, these modifications and changes based on the ideas of the present invention are still within the scope of protection of the claims of the present invention.

Claims

1. A high-transmission microwave-absorbing peak frequency tunable light window based on a thermotropic phase change material, characterized in that: The optical window comprises, from top to bottom, a transparent dielectric layer A (3), a thermally induced phase change material grating layer (5), a transparent dielectric layer B (6), and a transparent microwave shielding layer (8); the thermally induced phase change material grating layer (5) refers to a grating-like microstructure formed by thermally induced phase change material grating units (11) arranged on the upper surface of the transparent dielectric layer B (6); the thermally induced phase change material refers to a material whose conductivity can be reversibly and continuously changed under temperature-driven conditions; the absorption peak frequency refers to the frequency at which the optical window achieves maximum absorption; the absorption of the high-transmittance microwave absorption peak frequency adjustable optical window is caused by the resonance of two Fabry-Perot cavities, the first Fabry-Perot cavity being from the upper surface of the transparent dielectric layer A (3) to the upper surface of the transparent microwave shielding layer (8), and the second Fabry-Perot cavity being... The upper surface of the transparent dielectric layer A (3) is connected to the upper surface of the thermally induced phase change material grid layer (5); the optical thicknesses of the two Fabry-Perot cavities are different, resulting in different absorption peak frequencies; at temperature T1, the conductivity of the thermally induced phase change material grid layer (5) is poor, and the window is mainly dominated by the first Fabry-Perot cavity; at temperature T2, the conductivity of the thermally induced phase change material grid layer (5) increases, and the window is mainly dominated by the second Fabry-Perot cavity; within the temperature range from T1 to T2, T1 < T2, and as the temperature increases, the window changes from being dominated by the first Fabry-Perot cavity to being dominated by the second Fabry-Perot cavity, thereby achieving adjustable absorption peak frequency.

2. The high-transmission, thermally induced phase change material-based, tunable microwave absorption peak frequency adjustable light window according to claim 1, characterized in that: On the upper side of the transparent dielectric layer A (3), a single or multiple antireflective film A (2) and a single or multiple protective layer A (1) are arranged in parallel. On the lower side of the transparent microwave shielding layer (8), a single or multiple antireflective film B (9) and a single or multiple protective layer B (10) are arranged in parallel.

3. The high-transmission, thermally induced phase-transition material-based, tunable microwave absorption peak frequency adjustable light window according to claim 1, characterized in that: The thickness of the transparent medium layer B (6) is greater than half the thickness of the transparent medium layer A (3).

4. The high-transmission, thermally induced phase-transition-material-based, tunable microwave absorption peak frequency adjustable light window of claim 1, wherein: The thermally induced phase change materials include vanadium oxide, vanadium dioxide, vanadium pentoxide, vanadium-doped vanadium dioxide, tungsten-doped vanadium dioxide, and magnesium-doped vanadium dioxide.

5. The high-transmission, thermally induced phase-transition material-based, tunable microwave absorption peak frequency adjustable light window according to claim 1, characterized in that: The shape of the thermally induced phase change material grid unit (11) includes square grid, circular ring grid, triangular distributed circular ring and sub-circular ring array grid, metal grid based on randomly distributed circular ring, and metal ring nested array grid based on multi-period metal ring.

6. The high-transmission, thermally induced phase-transition-material-based, tunable microwave absorption peak frequency adjustable light window of claim 1, wherein: The material thickness of the thermally induced phase change material in the thermally induced phase change material grid layer (5) is greater than 50 nm.

7. The high-transmittance microwave absorption peak frequency tunable optical window based on thermally induced phase change material according to claim 1, characterized in that: The transparent medium layer A (3) and the transparent medium layer B (6) can be any transparent material, and the transparent material can be used as a transparent light window material that meets the requirements of the application.

8. The high-transmittance microwave absorption peak frequency tunable optical window based on thermally induced phase change material according to claim 1, characterized in that: The transparent microwave shielding layer (8) can be any transparent microwave shielding material. The transparent microwave shielding material can be used as a transparent material that meets the requirements of the application and has microwave shielding capability.

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