Dual-function metasurface sensors and their applications

Abstract

The present invention belongs to the field of electromagnetic metamaterial technology and specifically discloses a dual-function metasurface sensor capable of building displacement monitoring and hazardous gas detection, and its application. The sensor is composed of multiple unit structures arranged periodically. Each unit structure includes a rectangular dielectric layer with an upper metal layer on its upper surface and a lower metal layer on its lower surface. The upper metal layer has a pattern consisting of regular hexagonal slotted rings and elongated strips extending parallel to the long sides, starting from a set of opposite corners of the regular hexagon. The outer edges of one set of opposite sides of the regular hexagon are aligned with the long edges of the rectangular dielectric layer, and one of the other two sets of opposite sides has a slot. The pattern of the upper metal layer, which does not have a slot, is folded in half so that the long edges overlap, then split along the fold line to form two parts. The two parts are then joined together at their original long sides to form the pattern of the lower metal layer. This metasurface not only functions as a metal displacement sensor but also can sense changes in the content of hazardous gases in the surrounding environment.

Description

Technical Field

[0001] The present invention belongs to the technical field of electromagnetic metamaterials and relates to a dual-function metasurface sensor and applications thereof. Background Art

[0002] Metasurface sensors are devices that leverage the unique properties of metasurface structures to achieve high-sensitivity, high-resolution sensing and detection. Metasurfaces are metamaterials composed of periodic subwavelength artificial structures that can effectively control the propagation direction and amplitude of incident light or waves. Metasurface sensors exploit these properties to detect and identify targets by sensing electromagnetic waves emitted or reflected by them. They can also sense changes in surrounding gases, enabling safe monitoring of gas environments. With the continuous innovation and advancement of metasurfaces, researchers both domestically and internationally have conducted in-depth research on various aspects of metasurface sensors, including structural design and optimization, optical property analysis, sensing mechanism research, and multifunctional integration. The proposed metasurface sensor, which features dual functionalities for detecting metal displacement and environmental monitoring, has broad applications in industrial automation, electronic equipment movement monitoring, medical testing, and environmental pollution.

[0003] Structural health monitoring of industrial buildings can be achieved through the widespread deployment of structural displacement monitoring sensors throughout steel structures. Large-scale structural health monitoring technology measures structural response and environmental parameters, and through structural analysis and experimental comparison, enables the detection, identification, and assessment of structural damage. Structural damage can be caused by environmental influences (such as earthquakes, strong winds, uneven foundation subsidence), human damage, or long-term accumulated fatigue. Analyzing structural response data can reveal changes in structural stress or deformation, and most importantly, detect the presence of damage. Once damage is detected, appropriate warnings are issued. Industrial automation is the widespread adoption of automatic control and automatic adjustment devices in industrial production to replace manual operation of machines and machine systems. Under automated industrial production conditions, humans only indirectly oversee and supervise the production process. However, over time, factors such as mechanical vibration and error accumulation can cause large errors in automated production lines, leading to malfunctions. Consequently, a large number of sensors, particularly displacement sensors, are being introduced. Common commercially available displacement sensors include potentiometers, inductive sensors, capacitive sensors, eddy current sensors, and Hall effect sensors. This sensor detects displacement by irradiating electromagnetic waves of a specific frequency, absorbing the electromagnetic waves through the sensor, and detecting the frequency of the absorbed electromagnetic waves, providing a new way of displacement detection.

[0004] Dielectric constant is one of the most important material parameters in RF and microwave engineering and plays an important role in metasurface sensors. The dielectric constant of different gases affects their propagation characteristics in the electromagnetic field, which in turn affects the operation of metasurface sensors. When the environmental dielectric constant changes, the electromagnetic interaction between the metasurface sensor and the surrounding medium will change, affecting transmission characteristics such as reflection and transmission. In practical applications, the dielectric constant of the space environment will change with the changes in the content of certain harmful gases, and this change can be sensed by metasurface sensors. Therefore, by monitoring changes in the dielectric constant of the surrounding gas environment, metasurface sensors can be applied to the environmental field to achieve real-time monitoring and analysis of harmful gas monitoring in factories and harmful gas environmental pollution.

[0005] A metasurface sensor is a typical metamaterial functional device. By bringing the substance to be tested into contact with the metal resonant structural unit on the surface of the metasurface metamaterial sensor and monitoring the enhancement and offset of the electromagnetic wave signal reflected by the metasurface sensor, sensing detection of the sample to be tested can be achieved. The asymmetric honeycomb structure metasurface sensor designed by the present invention can achieve dual-functional characteristics and has better convenience. It can realize metal displacement sensing and environmental monitoring, and can be applied to steel displacement monitoring in industrial buildings to monitor whether there is damage. Once damage is detected, a corresponding warning will be given. The metasurface is affected by the changes in the surrounding gas environment, thereby affecting the dielectric constant, and is used in aspects such as harmful gas monitoring and early warning in industrial environments. Summary of the Invention

[0006] The present invention provides a dual-function metasurface sensor and its application, which can realize the dual-function sensor of metal displacement sensing and environmental monitoring.

[0007] In order to achieve the above objectives, the present invention adopts the following technical solution: a dual-function metasurface sensor, which is composed of a plurality of unit structures arranged periodically; each unit structure includes a rectangular dielectric layer, the upper surface of the dielectric layer is provided with an upper metal layer, and the lower surface is provided with a lower metal layer; the pattern of the upper metal layer includes a regular hexagonal slit ring and a long strip extending parallel to the long side direction starting from a set of opposite corners of the regular hexagon, the outer edges of a set of opposite sides of the regular hexagon are flush with the long side edges of the rectangular dielectric layer, and one of the other two sets of opposite sides is provided with a slit; the pattern of the upper metal layer without a slit is folded in half so that the long side edges overlap, and then split along the fold line to form two parts of the pattern, and then the original long side positions of the two parts of the pattern are fit together and spliced ​​to form the pattern of the lower metal layer.

[0008] Furthermore, the dielectric layer is made of polytetrafluoroethylene, has a dielectric constant of 2.1-2.2, and a thickness of 0.9-1.1 mm.

[0009] Furthermore, the length and width of the rectangular parallelepiped dielectric layer are 17.9-18.1 mm and 10.3-10.4 mm, respectively.

[0010] Furthermore, the upper metal layer and / or the lower metal layer are both made of copper material, with a thickness of 0.03 mm to 0.04 mm and an electrical conductivity of 5.96×10 7 S / m.

[0011] Furthermore, the outer side length and inner side length of the regular hexagonal slit ring are 5.9-6.1 mm and 4.8-4.9 mm respectively, and the width of each side is 0.9-1.1 mm.

[0012] Furthermore, there are two slits, one slit is located at 1 / 3 of the length of the regular hexagon, and the other slit is located at 1 / 2 of the length of the regular hexagon, and the angle between the line connecting the center points of the two slits and the line where the long side is located is 150°.

[0013] Furthermore, the width of the slit is 0.009-0.011 mm.

[0014] Furthermore, the length of the elongated strip corresponding to the regular hexagon is 8.95-9.05 mm, and the width is 0.9-1.1 mm.

[0015] Furthermore, the pattern of the upper metal layer is split into two parts by a seam; and the pattern of the lower metal layer is continuous and uninterrupted.

[0016] The present invention also relates to the application of the dual-function metasurface sensor in building safety monitoring and gas environment detection.

[0017] The present invention has the following beneficial effects:

[0018] 1) The dual-function metasurface sensor for metal displacement and environmental monitoring described in this invention requires no auxiliary power supply, is simple to operate, easy to detect, reusable, and has minimal requirements for the measurement environment. During measurement, the object to be measured is directly covered on the upper layer of the unit structure, significantly reducing costs.

[0019] 2) This invention achieves dual sensing capabilities: metal displacement and dielectric constant sensing. When the object being measured changes, not only is the amplitude shift noticeable, but the frequency shift is also very noticeable, enabling bidirectional detection.

[0020] 3) The materials used in the sensor are all conventional and easy to manufacture. In addition, the sensor has a relatively simple structure and is processed using a printed circuit board method, which is technically simple. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 A three-dimensional schematic diagram of the unit structure of a dual-function metasurface sensor for metal displacement monitoring and environmental monitoring;

[0022] Figure 2 Schematic diagram of the upper metal unit structure of the dual-function metasurface sensor for metal displacement monitoring and environmental monitoring;

[0023] Figure 3 Schematic diagram of the lower metal unit structure of the dual-function metasurface sensor for metal displacement monitoring and environmental monitoring;

[0024] Figure 4 The front overall structure diagram of the dual-function metasurface sensor for metal displacement monitoring and environmental monitoring;

[0025] Figure 5 The overall structure of the reverse side of the dual-function metasurface sensor for metal displacement monitoring and environmental monitoring;

[0026] Figure 6 (a) and (b) are respectively the front and back views of the dual-function metasurface sensor for metal displacement monitoring and environmental monitoring of Example 2;

[0027] Figure 7 Graphs showing the simulated and experimental reflection coefficients of the dual-function metasurface sensor for metal displacement monitoring and environmental monitoring according to Example 2;

[0028] Figure 8 (a) and (b) are respectively the simulation and experimental reflection coefficient curves of the dual-function metasurface sensor for metal displacement monitoring and environmental monitoring of Example 3 at different incident angles;

[0029] Figure 9 (a) and (b) are respectively the reflection coefficient curves of the dual-function metasurface sensor for metal displacement monitoring and environmental monitoring of Example 3 at different polarization angles;

[0030] Figure 10 This is a diagram of an experimental sample of metal displacement sensing performed by the dual-function metasurface sensor for metal displacement monitoring and environmental monitoring in Example 4;

[0031] Figure 11 (a)-(d) are simulation and experimental graphs showing the change in reflection coefficient of the dual-function metasurface sensor for metal displacement monitoring and environmental monitoring with metal rod displacement in Example 4;

[0032] Figure 12 This is a graph showing the change in reflection coefficient versus dielectric constant of the dual-function metasurface sensor for metal displacement monitoring and environmental monitoring according to Example 5;

[0033] Figure 13 This is a graph showing how the reflection coefficient of the dual-function metasurface sensor for metal displacement monitoring and environmental monitoring varies with the thickness c of the polytetrafluoroethylene dielectric layer of Example 6;

[0034] Figure 14 This is a graph showing how the reflection coefficient of the dual-function metasurface sensor for metal displacement monitoring and environmental monitoring in Example 6 changes with the width d of the slit ring.

[0035] Figure 15 This is a schematic diagram of the unit structure of the front and back sides of the dual-function metasurface sensor designed in Example 7 after removing the long strips from the metal structure.

[0036] Figure 16 This is a reflection curve simulation diagram of Example 7.

[0037] Figure 17 This is a reflection coefficient curve diagram of Example 7 during the displacement of the metal rod.

[0038] Figure 18 This is a curve diagram of the reflection coefficient of Example 7 as the dielectric constant changes. DETAILED DESCRIPTION

[0039] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

[0040] Example 1

[0041] like Figure 1-3 As shown, this embodiment provides a dual-function metasurface sensor for metal displacement monitoring and environmental monitoring, which is composed of a plurality of asymmetric unit structures arranged periodically. Each unit structure includes a rectangular parallelepiped polytetrafluoroethylene dielectric layer, an upper metal layer is provided on the upper surface of the dielectric layer, and a lower metal layer is provided on the lower surface. The pattern of the upper metal layer includes a regular hexagonal slotted ring and a long strip extending parallel to the long side direction starting from a set of opposite corners of the regular hexagon. The outer edges of one set of opposite sides of the regular hexagon are flush with the long side edges of the rectangular parallelepiped dielectric layer, and the outer edges of the other two sets of opposite sides are flush with the long side edges of the rectangular parallelepiped dielectric layer. One set of opposite sides is provided with slits, and the slits are asymmetrically arranged, with one slit located at 1 / 3 of the side length and the other slit located at 1 / 2 of the side length, and the angle between the line connecting the center points of the two slits and the line where the long side is located is 150°; the pattern of the upper metal layer without slits is folded in half so that the edges of the long sides overlap, and then split along the fold line to form two parts of the pattern, and then the original long sides of the two parts of the pattern are fitted and spliced ​​to form the pattern of the lower metal layer. When the structures on both sides are periodically extended, countless hexagons connected end to end will be formed.

[0042] The length and width of the dielectric layer are a=18mm and b=10.3mm respectively. The metal layer is made of copper material with a thickness of h=0.035mm and a conductivity of 5.96×10 7S / m. The outer side length of the regular hexagon is e=6mm, the width of the slit ring is d=1mm, and the width of the slit ring is f=0.1mm. The thickness of the polytetrafluoroethylene dielectric layer is c=1mm, and the total thickness of the unit structure is only H=h+c+h=1.07mm. When multiple unit structures are arranged closely and periodically, the overall structure is as follows Figure 4 and Figure 5 shown.

[0043] Example 2

[0044] The frequency-domain solver in CST Microwave Studio was used to optimize and simulate the unit cell structure of an asymmetric honeycomb metasurface. The boundary conditions were set as unit cells, the port was oriented from +Z to −Z, and the electric field was along the y-direction. The simulations yielded reflection data for a dual-function metasurface sensor for metal displacement monitoring and environmental monitoring in the 4 GHz-10 GHz frequency range, with a polytetrafluoroethylene dielectric layer having a dielectric constant of 2.2. A 180 mm × 176.6 mm experimental sample was fabricated using printed circuit board manufacturing technology. The actual sample is shown in the figure below. Figure 6 The experimental samples were tested, data was obtained and the simulation and experimental reflection coefficient curves were plotted as shown in Figure 7 As shown in the figure, the experimental data curves show similar trends to the simulated data curves. In the simulated data curve, the reflection coefficient curve shows a downward trend from the 4 GHz to 6.5 GHz frequency band, dropping to 0 at 6.5 GHz. Then, between 6.5 GHz and 6.8 GHz, the reflection coefficient gradually increases, reaching a maximum of 90%. Then, between 6.8 GHz and 7.3 GHz, the reflection coefficient continues to decrease to 0. Subsequently, between 7.3 GHz and 7.6 GHz, the reflection coefficient increases again, reaching 90%. At 8.2 GHz, the reflection coefficient drops to 0 again, and finally rises to approximately 80%. The experimental data curve shows that the sensor's reflection coefficient curve is greater than 80% in the 4 GHz to 5 GHz range, followed by three significant fluctuations between 6 GHz and 9 GHz, initially decreasing and then increasing. Minimum values ​​are reached at 6.4 GHz, 7.4 GHz, and 8.4 GHz, with the reflection coefficient below 10%. Then, within the 9 GHz-10 GHz frequency range, the reflection coefficient shows an upward trend, reaching 90%. Comparing the reflection coefficient curves of the experimental data with the simulated data shows that the experimental data curve of the experimental sample outperforms the simulated data curve. Therefore, in practical applications, the dual-function metasurface sensor for metal displacement monitoring and environmental monitoring proposed in this invention can demonstrate excellent sensing characteristics and achieve dual-function sensing.

[0045] Example 3

[0046] In order to study the functional mechanism of the dual-function metasurface sensor for metal displacement monitoring and environmental monitoring, the metasurface sensor is tested with electromagnetic waves at different incident angles and polarization angles, and the simulation results and experimental results are analyzed, such as Figure 8 and Figure 9 shown. Figure 8 (a) and (b) are the reflection coefficient curves when the electromagnetic wave is incident at different angles of incidence under simulation and experiment, respectively. In the simulation experiment, when the incident angle is 0°, the metasurface reflection coefficient curve has peaks at 6.9 GHz and 7.6 GHz, and the reflection coefficient is 0 at the three frequency points of 6.5 GHz, 7.3 GHz and 8.2 GHz. As the incident angle gradually increases, the first peak continues to shift to the left, and the overall reflection coefficient curve continues to increase. When the incident angle increases to 60°, the first peak frequency shifts to 5.6 GHz, and the reflection coefficient curve is higher than 35%. By conducting experimental tests on the experimental samples, Figure 8 (b) It can be seen that the reflection coefficient curve decreases with the increase of the incident angle. When the incident angle increases from 30° to 60°, the reflection coefficient curve changes little. As far as the experimental data curve is concerned, the metasurface sensor has the characteristic of being insensitive to the incident angle. Figure 9 (a) and (b) show the simulation and experimental data curves of the metasurface sensor when the electromagnetic wave is incident at different polarization angles. Under simulation conditions, the reflection coefficient curve changes significantly with the continuous increase of the polarization angle. When the polarization angle increases from 0° to 45°, the reflection coefficient of the metasurface sensor gradually increases, and the reflection coefficient can reach more than 90%. In the experiment, when the polarization angle increases from 0° to 30°, the reflection coefficient curve of the metasurface sensor does not change significantly. When the polarization angle increases to 45°, the overall reflection coefficient curve also shows a certain increase. Therefore, the metasurface sensor has the characteristic of being sensitive to polarization angle.

[0047] Example 4

[0048] In order to further explore the metal displacement measurement characteristics of the proposed dual-function metasurface sensor for metal displacement monitoring and environmental monitoring, a 1mm×176.6mm×1mm metal rod was placed on the backplane using printed circuit board manufacturing technology to measure its reflection coefficient. Figure 10 Figure 2 shows an experimental sample of a dual-function metasurface sensor for metal displacement monitoring and environmental monitoring. Based on the sensor unit structure, the midpoint of length a is taken as the origin. The simulated metal rod is positioned in the positive direction at 0.25-1.25, 1.75-2.75, and 3.25-4.25. The negative direction is -5.75-4.75, -7.25-6.25, and -8.75-7.75. Figure 11(a) and (b) are simulation graphs showing the reflection coefficient of the dual-function sensor on the asymmetric honeycomb metasurface as the metal rod is displaced in the positive and negative directions, respectively. When the metal rod is positioned between 0.25 and 1.25 degrees, the reflection coefficient is zero at 6.6 GHz, 7.1 GHz, and 8.3 GHz. When the metal rod is positioned between 1.75 and 2.75 degrees, the reflection coefficient is zero at 6.6 GHz and 8 GHz. When the metal rod is positioned between 3.25 and 4.25 degrees, the reflection coefficient is zero at 6.5 GHz, 7.3 GHz, and 8.3 GHz. The reflection coefficient curves for the metal rod at different positions in the negative direction also exhibit offsets. Figure 11 (c) and (d) show experimental plots of the reflection coefficient curves of the dual-function sensor based on the asymmetric honeycomb metasurface as the metal rod's position changes in the positive and negative directions, respectively. As the metal rod's position changes in the positive direction, the reflection coefficient decreases slightly. When the metal rod moves in the negative direction, the reflection coefficient increases. Therefore, changes in the reflection coefficient curve can be used to determine whether the metal rod has shifted. This demonstrates that the proposed dual-function metasurface sensor possesses the ability to measure metal displacement.

[0049] Example 5

[0050] In order to explore the environmental monitoring functional characteristics of the proposed dual-function metasurface sensor, a simulation of the metasurface sensor in an environment with a free space dielectric constant of 1.0-1.3 was performed. Figure 12 The following graph shows the metasurface sensor's reflection coefficient as a function of dielectric constant. It can be observed that the overall trend of the metasurface reflection coefficient curve remains almost consistent as the free-space dielectric constant ranges from 1.0 to 1.3, with only a leftward shift. Therefore, the proposed dual-function metasurface sensor for metal displacement monitoring and environmental monitoring can specifically sense the free-space dielectric constant of its surroundings, thereby fulfilling its environmental monitoring function.

[0051] Example 6

[0052] In order to analyze the influence of geometric parameters on the proposed dual-function metasurface sensor for metal displacement monitoring and environmental monitoring, the effects of different polytetrafluoroethylene dielectric layer thickness c and different slit ring width d on the reflection coefficient of the metasurface sensor were discussed respectively. Figure 13 The following graph shows the simulated reflection coefficient curves when the PTFE dielectric layer thickness c ranges from 0.5 mm to 1.5 mm, while other parameters remain unchanged. When the PTFE dielectric layer thickness c = 0.5 mm, the reflection coefficient exceeds 10% within the simulated frequency band. When the PTFE dielectric layer thickness c increases to 1.0 mm, the reflection coefficient reaches 0 at 6.5 GHz, 7.3 GHz, and 8.2 GHz. As the PTFE dielectric layer thickness c increases to 1.5 mm, the reflection coefficient remains above 10% within the simulated frequency band. Considering processing accuracy and cost factors, the metasurface sensor performs best when the PTFE dielectric layer thickness c = 1.0 mm.

[0053] The slit ring widths d of 0.5 mm, 1.0 mm and 1.5 mm were selected for simulation, and the corresponding reflection coefficient curves are shown as follows: Figure 14 As shown. When the slit ring width d is 0.5mm, the reflection coefficient of the metasurface sensor cannot reach 90%. When the slit ring width d=1.0mm, the reflection coefficient of the metasurface sensor can be greater than 90% in the 6.8 GHz-6.9 GHz and 7.6 GHz-7.7 GHz frequency bands. When the slit ring width d increases to 1.5mm, the reflection coefficient increases. By comparing the curves, the reflection effect is best when d=1.5mm. Considering the dual-function metasurface sensor functions of metal displacement monitoring and environmental monitoring, the selection can achieve a more intuitive monitoring effect. Therefore, the slit ring width d=1.0mm is selected to realize the dual-function sensing of metal displacement monitoring and environmental monitoring.

[0054] Example 7

[0055] In this embodiment, only regular hexagons are used as the metal structures on the front and back sides for simulation, and no long strip combination is used. The specific front and back structures are as follows: Figure 15 shown. Figure 16 The reflection curve simulation results for this case show that it only produces a high reflection coefficient of 76% at 7.4 GHz. Compared to Example 2, not only is the number of resonance peaks reduced, but the reflection efficiency is also reduced, making monitoring more difficult.

[0056] The effect of the metal rod displacement on the metasurface is detected. The corresponding movement method is the same as that in Example 4, that is, the midpoint of the length a is taken as the origin, and the positive direction of the simulated metal rod placement is 0.25-1.25, 1.75-2.75 and 3.25-4.25. The corresponding simulation curve is shown in Figure 4. Figure 17 As shown, it can be found that as the metal rod moves in the positive direction, the change trend of the reflection curve is very random. For example, when the metal rod is placed at 0.25-1.25 in the positive direction, the frequency of its resonance peak is 7.33 GHz and the reflection coefficient is 81%; when it moves to 1.75-2.75, the resonance peak frequency moves to 7.54 GHz, and the reflection coefficient decreases to 58%; when it is further transformed to 3.25-4.25, the corresponding two parameters are 7.58 GHz and 69%. Comparing these two parameters, it can be found that the change in its resonance peak frequency is not very obvious when it moves later, and the change in the reflection coefficient does not have continuity, so it does not have the desired sensor function. On the other hand, when the dielectric constant of the surrounding environment changes with Example 5, Figure 18The corresponding simulation curves are given, and it can be observed that the overall change trend is consistent, but it will move toward the low-frequency direction with the increase of the dielectric constant of the surrounding environment, indicating that the regular hexagonal structure plays a dominant role in the perception of the dielectric constant of the spatial environment, while the extended long strips play an important role in metal displacement monitoring.

[0057] In summary, the dual-function metasurface sensor proposed in this paper for metal displacement and environmental monitoring has excellent performance, capable of sensing both metal displacement and the dielectric constant of the spatial environment. Furthermore, the amplitude and width of the reflection coefficient can be dynamically adjusted by varying the polarization angle and the angle of incidence.

[0058] The above embodiments describe preferred embodiments of the present invention, but the present invention is not limited thereto. Within the technical concept of the present invention, various simple variations of the technical solution of the present invention may be made, including combining the various technical features in any other manner. These simple variations and combinations should also be regarded as disclosed in the present invention and fall within the scope of protection of the present invention. Therefore, the scope of protection of the patent of the present invention shall be based on the appended claims.

Claims

1. A dual-function metasurface sensor, characterized in that: The sensor is composed of multiple unit structures arranged periodically. Each unit structure includes a rectangular parallelepiped dielectric layer, an upper metal layer provided on the upper surface of the dielectric layer, and a lower metal layer provided on the lower surface. The pattern of the upper metal layer includes a regular hexagonal slotted ring and a long strip extending parallel to the long side starting from a set of opposite corners of the regular hexagon. The outer edges of one set of opposite sides of the regular hexagon are flush with the long side edges of the rectangular parallelepiped dielectric layer, and one of the other two sets of opposite sides is provided with a slot. The pattern of the upper metal layer without a slot is folded in half so that the long sides overlap, and then split along the fold line to form two parts of the pattern. The original long sides of the two parts are then joined and spliced ​​together to form the pattern of the lower metal layer. There are two slits, one slit is located at 1 / 3 of the length of the regular hexagon, and the other slit is located at 1 / 2 of the length of the regular hexagon; the angle between the line connecting the center points of the two slits and the line where the long side is located is 150°.

2. The sensor according to claim 1, characterized in that: The dielectric layer is made of polytetrafluoroethylene, has a dielectric constant of 2.1-2.2, and a thickness of 0.9-1.1 mm.

3. The sensor according to claim 2, characterized in that: The length and width of the rectangular dielectric layer are 17.9~18.1mm and 10.3~10.4mm respectively.

4. The sensor according to claim 1, wherein: The upper metal layer and / or the lower metal layer are both made of copper material, with a thickness of 0.03 mm to 0.04 mm and an electrical conductivity of 5.96×10 7 S / m.

5. The sensor according to claim 1, wherein: The outer and inner side lengths of the regular hexagonal slit ring are 5.9~6.1mm and 4.8~4.9mm respectively, and the width of each side is 0.9~1.1mm.

6. The sensor according to claim 1, wherein: The width of the slit is 0.009-0.011 mm.

7. The sensor according to claim 1, characterized in that: The length of the extended strip corresponding to the regular hexagon is 8.95~9.05mm, and the width is 0.9~1.1mm.

8. The sensor according to claim 1, wherein: The pattern of the upper metal layer is split into two parts by a seam; the pattern of the lower metal layer is continuous and uninterrupted.

9. Application of the dual-function metasurface sensor according to any one of claims 1 to 8 in the fields of building safety monitoring and gas environment detection.

Images