A Stretchable Smart Window Based on an Elastic Substrate and Its Transmittance Adjustment Method

Abstract

The present invention belongs to the technical field of intelligent windows, and proposes a stretchable intelligent window based on an elastic substrate and a method for adjusting its light transmittance. Aiming at the problems of low light transmittance and solar modulation ability in VO2 thermochromic windows, as well as the inability to continuously adjust the transmittance in the solar radiation band, by setting an elastic substrate and adding a silica layer on the vanadium dioxide layer, the addition of the silica layer promotes a smooth change in the refractive index, increases the transmittance in the visible light range, and realizes the optimization of the optical performance of a single-layer VO2 thermochromic window. Combining with the stretchability of the elastic substrate, by stretching the elastic substrate, a continuous change in the light transmittance in the solar radiation band is achieved, overcoming the problem of the singularity of the solar radiation regulation ability, and the indoor temperature of a building can be adjusted in real time according to the external environmental temperature, achieving the purpose of improving the human comfort in the building interior and saving fossil energy.

Description

Technical Field

[0001] The present invention belongs to the technical field of intelligent windows, and particularly relates to a stretchable intelligent window based on an elastic substrate and a method for adjusting its light transmittance. Background Art

[0002] Global residential buildings consume a large amount of energy, accounting for a relatively high proportion of the total global energy consumption. More importantly, about half of this energy is used for various aspects of building services to maintain living comfort, such as lighting requirements, air conditioning cooling and heating requirements, etc. Using intelligent windows to replace traditional glass is an effective way to reduce building energy consumption. Generally speaking, thermochromic windows are considered the most ideal intelligent windows, which can autonomously adjust the transmittance of solar radiation according to changes in the external temperature, that is, having a high infrared transmittance at low temperatures and a low infrared transmittance at high temperatures.

[0003] Vanadium dioxide (VO2), as a thermochromic material for adjusting the transmittance of solar radiation, changes its optical properties at a critical transition temperature (T c ) of 68°C. VO2 below the phase transition temperature is in an insulator state and is transparent to near-infrared light; when the temperature is higher than the phase transition temperature, VO2 switches to a metal state, and the transparency in the near-infrared region suddenly decreases. Due to the reversible metal-insulator transition (MIT) property of VO2, VO2 is widely used in the field of thermochromic windows.

[0004] The inventors found that due to the low visible light transmittance (Tlum, avg < 40%) and solar modulation ability (ΔTsol < 10%) of VO2, it seriously hinders the commercialization of VO2-based intelligent windows. Although various optimization strategies and design methods have been developed to improve the optical performance of thermochromic windows, such as surface micro-nano structures, anti-reflection thin films, and spherical shell structures, etc., although the above methods can optimize the optical performance of thermochromic windows, the degree of optimization is small, and the function of VO2-based thermochromic windows is only binary-switchable solar radiation regulation, that is, "transmit / shield" solar radiation. Therefore, traditional thermochromic windows cannot achieve continuous adjustment of the transmittance in the solar radiation band, and it is difficult to further improve human comfort; that is, traditional thermochromic windows have the problem of the singularity of solar radiation regulation ability, that is, only two states of low temperature and high temperature, which cannot meet the needs of human comfort. Summary of the Invention

[0005] In order to solve the above problems, the present invention proposes a stretchable intelligent window based on an elastic substrate and a method for adjusting its light transmittance, which makes full use of the stretchability and resilience of the elastic substrate to achieve continuous regulation of the light transmittance and meet the needs of people for a comfortable life.

[0006] To achieve the above object, in a first aspect, the present invention provides a stretchable smart window based on an elastic substrate, adopting the following technical solutions:

[0007] A stretchable smart window based on an elastic substrate, comprising an elastic substrate;

[0008] A plurality of vanadium dioxide layers are fixed on the elastic substrate, and a silica layer is fixed on one side of each vanadium dioxide layer away from the elastic substrate.

[0009] Further, the material of the elastic substrate is polydimethylsiloxane.

[0010] Further, the distribution of the plurality of vanadium dioxide layers on the elastic substrate is a periodic array structure.

[0011] Further, according to the complex refractive indices of the vanadium dioxide layer and the elastic substrate, a geometric model is constructed; according to the constructed geometric model, the spectral transmittance is simulated; based on the standard luminous efficiency function based on vision and the solar irradiance spectrum, the spectral transmittance is converted into the optical characteristics of the smart window; by evaluating the optical characteristics of the smart window, the size of the vanadium dioxide layer is determined.

[0012] Further, according to the complex refractive indices of the vanadium dioxide layer, the silica layer and the elastic substrate, a geometric model is constructed; according to the constructed geometric model, the spectral transmittance is simulated; based on the standard luminous efficiency function based on vision and the solar irradiance spectrum, the spectral transmittance is converted into the optical characteristics of the smart window; by evaluating the optical characteristics of the smart window, the size of the silica layer is determined.

[0013] Further, the optical characteristics of the smart window include the average visible light transmittance and the solar modulation ability.

[0014] Further, the sizes of the vanadium dioxide layer and the silica layer both include the thickness size and the cross-sectional size perpendicular to the thickness direction.

[0015] Further, the optical characteristics of the smart window are evaluated by the FOM index; the FOM index is equal to the ratio of the solar modulation ability to the maximum solar modulation ability, plus half of the sum of the ratio of the average visible light transmittance to the maximum average visible light transmittance.

[0016] To achieve the above object, in a second aspect, the present invention further provides a method for adjusting the light transmittance of a stretchable smart window based on an elastic substrate, adopting the following technical solutions:

[0017] A method for adjusting the light transmittance of a stretchable smart window based on an elastic substrate, adopting the stretchable smart window based on an elastic substrate as described in the first aspect, stretching the elastic substrate, and continuously adjusting the solar spectral transmittance.

[0018] Further, a geometric model is constructed based on the size of the vanadium dioxide layer, the size of the silicon dioxide layer, and the period of the periodic array structure; the elastic substrate is stretched in the x-direction and the y-direction, and the optical properties of the geometric model are simulated and calculated under different stretching strengths;

[0019] The optical properties are converted into the average visible light transmittance before and after stretching and the solar modulation ability before and after stretching, and the improvement degree of the optical performance of the smart window corresponding to different stretching degrees is obtained.

[0020] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0021] The present invention aims at energy conservation and emission reduction and improving human comfort. Aiming at the problems of low transmittance and solar modulation ability of VO2 thermochromic windows, as well as the problem that the transmittance in the solar radiation band cannot be continuously adjusted, a stretchable thermochromic window with different temperature adaptabilities is designed; by setting an elastic substrate and adding a silicon dioxide layer on the vanadium dioxide layer, adding the silicon dioxide layer promotes a smooth change in the refractive index, increases the transmittance in the visible light range, realizes the optimization of the optical performance of the single-layer VO2 thermochromic window, and combines the stretchability of the elastic substrate. By stretching the elastic substrate, the continuous change of the transmittance in the solar radiation band is realized, the problem of the singularity of the solar radiation regulation ability is overcome, the indoor temperature of the building can be adjusted in real time according to the external environmental temperature, and the purpose of improving the human comfort in the building and saving fossil energy is achieved. Description of the Drawings

[0022] The specification drawings forming a part of this embodiment are used to provide a further understanding of this embodiment. The schematic embodiments and descriptions thereof of this embodiment are used to explain this embodiment and do not constitute an improper limitation on this embodiment.

[0023] Figure 1 It is a schematic diagram of a single-layer VO2 micro-nano structure according to Embodiment 1 of the present invention;

[0024] Figure 2 It is a schematic diagram of the distribution structure of VO2 on an elastic substrate according to Embodiment 1 of the present invention;

[0025] Figure 3 It is an FOM result diagram of a single-layer VO2 micro-nano structure according to Embodiment 1 of the present invention;

[0026] Figure 4 It is a schematic diagram of a double-layer SiO2-VO2 micro-nano structure according to Embodiment 1 of the present invention;

[0027] Figure 5 It is a schematic diagram of the distribution structure of double-layer SiO2-VO2 on an elastic substrate according to Embodiment 1 of the present invention;

[0028] Figure 6 FOM result diagram of the double-layer SiO2-VO2 micro-nano structure of Embodiment 1 of the present invention;

[0029] Figure 7 Single-layer transmittance analysis diagram of Embodiment 1 of the present invention;

[0030] Figure 8 Double-layer SiO2-VO2 transmittance analysis diagram of Embodiment 1 of the present invention;

[0031] Figure 9 Comparison and analysis diagram of the average visible light transmittance and solar modulation ability of single-layer VO2 and double-layer SiO2-VO2 of Embodiment 1 of the present invention;

[0032] Figure 10 Transmittance of the smart window of Embodiment 1 of the present invention varying with the tensile strength;

[0033] Figure 11 Comparison and analysis diagram of the average visible light transmittance before and after stretching and the solar modulation ability before and after stretching of the smart window under different stretching degrees of Embodiment 1 of the present invention;

[0034] Among them, 1. Vanadium dioxide layer; 2. Elastic substrate; 3. Silicon dioxide layer. Specific implementation manner

[0035] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0036] It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present application belongs.

[0037] Embodiment 1:

[0038] As described in the background art, for traditional VO2-based smart windows, although the characteristics that VO2 is in an insulator state and a metal state below and above the phase transition temperature respectively can be used to adjust the light transmittance of the smart window; however, the VO2-based smart window can only achieve binary switching of solar radiation regulation, that is, transmitting solar radiation and shielding solar radiation. The solar radiation regulation ability is single, with only two states of low temperature and high temperature, and cannot achieve continuous adjustment of the transmittance in the solar radiation band, unable to meet the requirements of human comfort.

[0039] Regarding the above problems, as Figure 4As shown in the figure, this embodiment provides a stretchable smart window based on an elastic substrate. The smart window can be understood as a thermochromic window, including an elastic substrate 2. The elastic substrate material can be selected from polydimethylsiloxane (PDMS) or other elastic materials. A plurality of vanadium dioxide layers 1 are fixed on the elastic substrate 2, and a silicon dioxide layer 3 is fixed on one side of each vanadium dioxide layer 1 away from the elastic substrate 2; As Figure 2 and Figure 5 shown, the distribution of the plurality of vanadium dioxide layers 1 and the plurality of silicon dioxide layers 3 on the elastic substrate 1 can be a periodic array structure, and the connection surfaces of the vanadium dioxide layer 1 and the silicon dioxide layer 3 can coincide. Specifically, adding the silicon dioxide layer 3 promotes a smooth change in the refractive index, increases the transmittance in the visible light range, and realizes the optimization of the optical performance of the single-layer VO2 thermochromic window. Combining the stretchability of the elastic substrate 2, by stretching the elastic substrate 2, a continuous change in the transmittance in the solar radiation band is realized, overcoming the problem of the singularity of the solar radiation regulation ability. The indoor temperature of the building can be adjusted in real time according to the external environmental temperature, achieving the purpose of improving the human comfort in the building interior and saving fossil energy.

[0040] In this embodiment, the optimization of the stretchable smart window based on the elastic substrate and the process of adjusting its light transmittance can be as follows:

[0041] S1. Establish a thermochromic window model based on single-layer VO2. According to the complex refractive indices of the vanadium dioxide layer 1 and the elastic substrate 2, construct a geometric model; Based on the constructed geometric model, simulate the spectral transmittance; Based on the standard luminous efficiency function based on vision and the solar irradiance spectrum, convert the spectral transmittance into the optical characteristics of the smart window; By evaluating the optical characteristics of the smart window, determine the size of the vanadium dioxide layer; Specifically, it includes the following steps:

[0042] S1.1. As Figure 1 and Figure 2 shown, determine the relevant geometric structure parameters according to the micro-nano structure system, including the width W, height H of the vanadium dioxide layer 1, and the period P of the micro-nano structure;

[0043] S1.2. Optionally, import the complex refractive indices of the vanadium dioxide layer 1 and the elastic substrate 2 into the FDTD Solution electromagnetic simulation software and construct a geometric model. The geometric model includes the elastic substrate 2 and the vanadium dioxide layer 1 located on the elastic substrate 2; the period of the simulation structure can be fixed at 400 nm. For the periodic array simulation, periodic boundary conditions are used along the x and y directions, and a Perfectly Matched Layer (PML) is used for the top and bottom boundaries. Calculate the optical properties of the periodic micro-nano structure in the wavelength range of 0.3 - 2.5 μm based on the finite-difference time-domain theory, including the spectral reflectance R λ and the spectral transmittance T λ ;

[0044] S1.3. The obtained spectral transmittance T λ can be utilized. Based on the visual standard luminous efficiency function Φ lum and the AM1.5 solar irradiance spectrum Φ sol , convert the spectral transmittance data into the optical properties of the thermochromic smart window, including the visible light average transmittance T lum，avg and the solar modulation ability ΔT sol :

[0045]

[0046]

[0047] ΔT sol = T sol (T < T c ) - T sol (T > T c ) (3)

[0048] T lum,avg = (T lum (T < T c ) + T lum (T > T c )) / 2 (4)

[0049] where Φ lum is the visual standard luminous efficiency function; Φ sol is the AM1.5 solar irradiance spectrum; T(λ) is the spectral transmittance; T c is the phase transition temperature of VO2; λ is the incident light wavelength. Among them, the visible light average transmittance represents the amount of visible light transmitted that is useful for human vision under normal conditions, and the solar modulation ability represents the modulation of the solar radiation energy passing through the window;

[0050] S1.4. As can be known from previous studies, the thickness and width of the vanadium dioxide layer 1 have a very significant impact on the average visible light transmittance and the solar modulation ability. When the thickness of the vanadium dioxide layer 1 is small or the width is narrow, the average visible light transmittance is large, but the solar modulation ability is insufficient, and the function of the smart window cannot be truly realized; on the contrary, when both the thickness or width of the vanadium dioxide layer 1 is large, the solar modulation ability is obvious, but the light transmittance is low, making it difficult to meet the normal visual needs of humans. To determine the optimal thickness and width of the single-layer VO2, the FOM is used to evaluate the average visible light transmittance T lum，avg and the solar modulation ability ΔT sol of two performance indicators to seek the optimal parameters of the vanadium dioxide layer 1. Among them, the FOM index is equal to the ratio of the solar modulation ability to the maximum solar modulation ability, plus half of the sum of the ratio of the average visible light transmittance to the maximum average visible light transmittance. The FOM formula is as follows:

[0051]

[0052] Finally, by finding the maximum value of the FOM, optionally, when the height of the vanadium dioxide layer 1 is 100 nm and the width is 370 nm, it has good average visible light transmittance and excellent solar modulation ability, which are T lum，avg = 0.458 and ΔT sol = 0.163 respectively.

[0053] S2. Based on the complex refractive indices of the vanadium dioxide layer 1, the silicon dioxide layer 3, and the elastic substrate 2, a geometric model is constructed; based on the constructed geometric model, the spectral transmittance is simulated; based on the standard luminous efficiency function of vision and the solar irradiance spectrum, the spectral transmittance is converted into the optical properties of the smart window; by evaluating the optical properties of the smart window, the size of the silicon dioxide layer 3 is determined. Although the height and width of the vanadium dioxide layer 1 determined in step S1 comprehensively consider the two optical properties of the thermochromic window, its visible light transmittance and solar modulation ability are still low. Therefore, the single-layer VO2 micro-nano structure is further optimized to increase the average visible light transmittance T lum，avg and the solar modulation ability ΔT sol The specific steps are as follows:

[0054] S2.1. Using the principle of an antireflection film, a silicon dioxide layer 3 in the form of SiO2 nanoblocks is added above the vanadium dioxide layer 1 to promote a smooth change in the refractive index and achieve an increase in the transmittance in the visible light range;

[0055] S2.2. Import the complex refractive index of the silica layer 3 material into the FDTD Solution electromagnetic simulation software and construct a geometric model. The geometric model successively includes the elastic substrate 2, the vanadium dioxide layer 1 spacer located on the elastic substrate 2, and the silica layer 3 top layer. Optionally, the simulation period is consistent with that of the single-layer VO2 model, i.e., P = 400 nm. From Figure 3 the results shown, fix the height of the VO2 nanoblock as H2 = 100 nm, and study the influence of the width W of the nanoblock and the height H1 of the SiO2 nanoblock on the optical properties of the thermochromic window. The setting of other boundary conditions is consistent with the above. Calculate the optical properties of the periodic micro-nano structure in the wavelength range of 0.3 - 2.5 μm based on the finite-difference time-domain theory, including the spectral reflectivity R λ and the spectral transmittance T λ ;

[0056] S2.3. Convert the spectral transmittance data into the visible light average transmittance T lum，avg and the solar modulation ability ΔT sol . Since the maximum values of the visible light average transmittance and the solar modulation ability appear at different widths W and SiO2 thicknesses H1, the FOM is used to evaluate the two performance indicators (T lum，avg and ΔT sol ) to find the width W of the nanoblock and the thickness H1 of SiO2, as Figure 6 shown. After analysis, finally determine that the width W of the nanoblock is 370 nm and the thickness H1 of SiO2 is 110 nm. Figure 7 And Figure 8 is the transmittance comparative analysis of the double-layer micro-nano structure and the single-layer micro-nano structure. It can be seen from the figure that when VO2 is in the insulating state, the transmittance of the optimized thermochromic window model at wavelengths of 0.6 - 1.5 μm increases significantly, and the maximum value of the transmittance in the visible light range increases from 0.57 to 0.65; when VO2 is in the metallic state, the transmittance of the optimized thermochromic window model at wavelengths of 0.6 - 2.0 μm increases significantly, and the maximum value of the transmittance in the visible light range increases from 0.46 to 0.54. Compare and analyze the performance parameters of the double-layer micro-nano structure and the single-layer micro-nano structure, as Figure 9 shown. Compared with the single-layer VO2 micro-nano structure, the low-temperature visible light transmittance T lum (T < T c ) of the double-layer VO2 thermochromic window increases from 49.7% to 53.8%, and the high-temperature visible light transmittance T lum (T > T c ) increases from 41.8% to 44.3%, and the solar modulation ability ΔT solIt increases from 16.3% to 18.4%, from which the good performance of the double-layer VO2 thermochromic window can be seen.

[0057] S3. Since the traditional thermochromic window has the problem of the singularity of the solar radiation regulation ability, that is, there are only two states of low temperature and high temperature, which cannot meet the human comfort, so this embodiment proposes a method to realize the continuous adjustment of the solar spectral transmittance by stretching the thermochromic window. The target performance of the thermochromic window is: when it is very cold outdoors (T << T c ), the thermochromic window remains transparent to light in the entire solar spectral range; when it is relatively warm outdoors (T < T c ), the transmittance of visible light is relatively high, and a certain near-infrared transmittance is maintained; when it is very hot outdoors (T > T c ), a certain transmittance of visible light is maintained, and light in the near-infrared range is blocked from entering the house to heat the interior. The specific measures include the following steps:

[0058] S3.1. Combine the optimized width W and height H of the vanadium dioxide layer 1, as well as the height H1 of the silicon dioxide layer 3 and the period P of the micro-nano structure, etc., to analyze the influence of different stretching strengths on the performance of the thermochromic window. Achieve continuous changes in the solar spectral transmittance through mechanical stretching. Build an optimized geometric model in the FDTD Solution electromagnetic simulation software. The period of the micro-nano structure remains unchanged at P = 400 nm before being stretched. When the elastic substrate 2 is stretched in both the x-direction and the y-direction, the stretching strength α ranges from 0 to 100%, and the new period of the deformed structure is P(1 + α). Calculate the optical properties of the micro-nano model under different stretching strengths α, including the spectral reflectance R λ and the spectral transmittance T λ .

[0059] The transmittance spectrum diagram calculated by using the FDTD simulation software is as shown in Figure 10 . It can be seen from the figure that when VO2 is in the insulating state, when the stretching strength α increases from 0 to 40%, the overall light transmittance of the thermochromic window gradually increases, but the increase amplitude is small; when the gap between VO2 nano-blocks continues to increase, that is, when α increases from 40% to 80%, the light transmittance of the thermochromic window increases significantly, especially in the ultraviolet and visible light regions. Thus, it can be seen that the continuous change of the transmittance within the solar spectral range can be realized by mechanically stretching the elastic substrate of this structure.

[0060] S3.2. Convert the spectral transmittance data into the average visible light transmittance T lum，stretch before and after stretching and the solar modulation ability ΔT sol，stretch before and after stretching:

[0061] ΔT sol,stretch = T sol,α＝0～100％(T < T c ) - T sol,α＝0 (T > T c ) (6)

[0062] T lum,stretch =(T lum,α＝0～100％ (T < T c ) + T lum,α＝0 (T > T c )) / 2 (7)

[0063] Where α is the tensile strength. Figure 11 are the average visible light transmittance T lum，stretch before and after stretching and the solar modulation ability ΔT sol，stretch before and after stretching of the thermochromic window under different stretching degrees. From the figure, it can be seen that as the tensile strength α gradually increases, the average visible light transmittance T lum，stretch before and after stretching and the solar modulation ability ΔT sol，stretch before and after stretching both increase. When the tensile strength α is less than 40%, the increase in the average visible light transmittance is small; however, when α is greater than 40%, the average visible light transmittance increases rapidly. Thus, through the mechanical stretching method, this structure realizes a large increase in the average visible light transmittance and the solar modulation ability, and can better meet people's needs for a comfortable life.

[0064] In this embodiment, aiming at the problem of poor optical performance of the single-layer VO2 thermochromic window, this embodiment optimizes the structure of the single-layer VO2 thermochromic window, realizing the common increase of the average visible light transmittance T lum，avg and the solar modulation ability ΔT sol ; aiming at the problem of the singularity of the solar radiation regulation ability of the VO2-based thermochromic window, realizing the continuous adjustment of the transmittance in the solar radiation band, thereby further improving human comfort.

[0065] Example 2:

[0066] This embodiment provides a method for adjusting the light transmittance of a stretchable smart window based on an elastic substrate. The stretchable smart window based on an elastic substrate described in Example 1 is adopted, and the elastic substrate is stretched to continuously adjust the solar spectrum transmittance.

[0067] Specifically, according to the size of the vanadium dioxide layer 1, the size of the silicon dioxide layer 3, and the period of the periodic array structure, a geometric model is constructed; the elastic substrate 2 is stretched in the x direction and the y direction, and the optical characteristics of the geometric model under different tensile strengths are simulated and calculated; the optical characteristics are converted into the average visible light transmittance before and after stretching and the solar modulation ability before and after stretching, and the improvement degree of the optical performance of the corresponding smart window at different stretching degrees is obtained.

[0068] The above are only the preferred embodiments of this embodiment and are not intended to limit this embodiment. For those skilled in the art, this embodiment can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of this embodiment shall be included within the protection scope of this embodiment.

Claims

1. A stretchable intelligent window based on an elastic substrate, characterized in that, Comprising an elastic substrate; A plurality of vanadium dioxide layers are fixed on the elastic substrate, and a silica layer is fixed on one side of each vanadium dioxide layer away from the elastic substrate; the distribution of the plurality of vanadium dioxide layers on the elastic substrate is a periodic array structure; the transmittance of the solar radiation band can be continuously changed by stretching the elastic substrate.

2. The stretchable intelligent window based on an elastic substrate according to claim 1, characterized in that, The elastic substrate material is polydimethylsiloxane.

3. A design method of a stretchable intelligent window based on an elastic substrate, which adopts the stretchable intelligent window based on an elastic substrate according to any one of claims 1-2, characterized in that, Construct a geometric model based on the complex refractive indices of the vanadium dioxide layer, the silica layer and the elastic substrate; simulate the spectral transmittance based on the constructed geometric model; convert the spectral transmittance into the optical properties of the smart window based on the standard luminous efficiency function of vision and the solar irradiance spectrum; determine the size of the silica layer by evaluating the optical properties of the smart window.

4. The design method of a stretchable intelligent window based on an elastic substrate according to claim 3, characterized in that, The optical properties of the smart window include the average visible light transmittance and the solar modulation ability.

5. The design method of a stretchable intelligent window based on an elastic substrate according to claim 3, characterized in that, The sizes of the vanadium dioxide layer and the silica layer both include the thickness dimension and the cross-sectional dimension perpendicular to the thickness direction.

6. The design method of a stretchable intelligent window based on an elastic substrate according to claim 3, characterized in that, By FOM evaluating the optical properties of the smart window with an index; FOM The index is equal to the ratio of the solar modulation ability to the maximum solar modulation ability, plus half of the sum of the ratio of the average visible light transmittance to the maximum average visible light transmittance.

7. A light transmittance adjustment method of a stretchable intelligent window based on an elastic substrate, characterized in that, The stretchable smart window based on the elastic substrate described in any one of claims 1-2 is adopted, and the elastic substrate is stretched to continuously adjust the solar spectral transmittance.

8. The light transmittance adjustment method of a stretchable intelligent window based on an elastic substrate according to claim 7, characterized in that, Construct a geometric model based on the size of the vanadium dioxide layer, the size of the silica layer and the period of the periodic array structure; stretch the elastic substrate in the x-direction and the y-direction, and simulate and calculate the optical properties of the geometric model under different stretching strengths; Convert the optical properties into the average visible light transmittance before and after stretching and the solar modulation ability before and after stretching, and obtain the improvement degree of the optical performance of the smart window corresponding to different stretching degrees.

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