A curved conformal transparent electromagnetic shielding structure and a manufacturing method thereof

Abstract

The application provides a curved surface conformal transparent electromagnetic shielding structure and a manufacturing method thereof. The shielding structure comprises two layers of curved surface transparent substrates and a biomimetic step strain stretchable metal mesh. The metal mesh is embedded and encapsulated between the two layers of curved surface transparent substrates. The metal mesh is a biomimetic spider web S-shaped stretchable mesh which is matched with the curved surface stress distribution, and the tensile strain of the metal mesh is distributed in a step gradient from the center to the edge of the curved surface. The metal mesh is a narrow line width and high aspect ratio structure. The application obtains a high-performance and high-stability curved surface transparent electromagnetic shielding structure through the biomimetic spider web type step strain stretchable mesh structure design, combined with nano-imprinting, electrodeposition, stripping transfer and curved surface hot pressing composite process. The shielding structure has high light transmittance, low sheet resistance and high electromagnetic shielding energy efficiency as a whole, and the light transmittance and conductive performance are uniform in the whole curved surface.

Description

Technical Field

[0001] This invention relates to the field of aerospace electronic devices and optoelectronic systems, and more specifically to a curved conformal transparent electromagnetic shielding structure and its fabrication method. Background Technology

[0002] With the rapid development of optoelectronic systems towards integration and miniaturization, curved optical windows are finding increasingly widespread applications in aerospace, automotive displays, and smart wearables. Curved optical windows not only need to meet the requirements of wide-band high-transmittance imaging, but also need to possess excellent electromagnetic shielding performance to resist interference from complex external electromagnetic environments on internal high-precision electronic equipment, thereby improving the equipment's electromagnetic interference resistance and operational stability.

[0003] Currently, the methods for realizing curved transparent electromagnetic shielding materials mainly fall into three categories: Planar flexible conductive film bonding method: Conductive films such as metal mesh and silver nanowires are prepared on a planar PET substrate and then bonded to a curved optical window. In this method, the planar conductive material cannot adapt to the complex curvature changes of the curved surface, resulting in stress mismatch, wrinkles, and cracks, leading to poor uniformity of conductivity and light transmission, and even interruption of the conductive path. At the same time, the bonding process is prone to air bubbles, local debonding, and insufficient interfacial adhesion, and delamination failure is likely to occur after long-term use.

[0004] Direct deposition on curved surfaces: This method involves directly depositing thin layers of metal or ITO onto curved substrates via magnetron sputtering or thermal deposition. This method requires high-vacuum equipment, resulting in high production costs. Uneven distances between the curved substrate and the target material lead to poor film thickness uniformity and uneven distribution of light transmittance and shielding efficiency. Furthermore, the thickness of the conductive film is negatively correlated with light transmittance, presenting a challenge of not being able to simultaneously achieve high light transmittance and high shielding efficiency. Additionally, the film is directly exposed on the surface, resulting in poor scratch resistance.

[0005] Direct printing on curved surfaces: This method uses electrohydraulic inkjet printing and other techniques to fabricate metal meshes on curved substrates. The conductive linewidths produced by this method are mostly above 10 μm, visible to the naked eye, with low light transmittance and negatively impacting visual quality. The printing material is metal nanowires / particles, which have poor conductivity, and the shielding efficiency is difficult to exceed 20 dB at 85% light transmittance. Variations in the curvature of the curved surface lead to inconsistent angles between the print head and the substrate, resulting in poor linewidth uniformity and consequently uneven light transmittance and conductivity. Furthermore, the exposed mesh structure has poor scratch resistance.

[0006] In summary, existing curved transparent electromagnetic shielding materials generally suffer from problems such as stress mismatch leading to easy failure, difficulty in balancing light transmission and shielding performance, poor uniformity, weak scratch resistance, and high manufacturing costs, failing to meet the application requirements of high-performance curved optical windows. Therefore, developing a conformal, highly transparent electromagnetic shielding structure with high light transmission, high conductivity, high shielding, excellent uniformity, and durability, along with its fabrication method, has become an urgent technical challenge to be solved in this field. Summary of the Invention

[0007] The purpose of this invention is to provide a curved conformal transparent electromagnetic shielding structure and its manufacturing method. By designing a biomimetic spider web-type stepped strain stretchable grid structure, combined with nanoimprinting, electrodeposition, peeling transfer and curved hot pressing composite process, it solves problems such as curved conformal stress mismatch, contradiction between light transmission and shielding performance, poor uniformity and weak scratch resistance, and achieves high performance and high stability curved transparent electromagnetic shielding.

[0008] To achieve the above objectives, the present invention provides the following solution: A curved conformal transparent electromagnetic shielding structure includes two curved transparent substrates and a biomimetic stepped strain stretchable metal mesh. The metal mesh is embedded and encapsulated between two curved transparent substrates. The metal mesh is a spider web-like S-shaped stretchable mesh that matches the stress distribution of the curved surface, and the tensile strain of the metal mesh is gradually distributed in a stepped manner from the center to the edge of the curved surface. The metal mesh has a narrow linewidth and a high aspect ratio structure.

[0009] Furthermore, the line width of the metal mesh is 1-15 μm, the aspect ratio is not less than 1:1, and the mesh period deviation does not exceed 10%. The overall light transmittance of the shielding structure is >70%, and the light transmittance deviation of the entire curved surface is within 10%; the sheet resistance of the shielding structure is ≤1Ω / sq, and the conductivity deviation of the entire curved surface is within 20%.

[0010] Furthermore, the metal mesh is made of any one or more alloys of copper, nickel, platinum, gold, silver, and tin; the curved transparent substrate is made of plexiglass, polycarbonate, transparent resin, or inorganic glass.

[0011] Furthermore, a thermoplastic film layer is disposed between the two curved transparent substrates, and the metal mesh is adhered to the curved transparent substrate through the thermoplastic film layer; the thermoplastic film layer is one or more composites of PVB, PVA, TPU, PU, ​​and PE polymer thermoplastic materials.

[0012] This invention also provides a method for manufacturing a curved conformal transparent electromagnetic shielding structure, applicable to the fabrication of the aforementioned curved conformal transparent electromagnetic shielding structure, comprising the following steps: S1. Based on the stress distribution data of the target surface, design a biomimetic stepped strain stretchable metal mesh structure that matches the tensile strain of the surface. S2. Based on the designed metal mesh structure, a nanoimprint mold is prepared. A high aspect ratio groove structure with corresponding pattern is formed on the surface of a flexible substrate by nanoimprinting. A conductive seed layer is prepared at the bottom of the groove. A conductive metal mesh is formed by self-mask photolithography and electrodeposition. Then, the metal mesh is peeled off using a micro-adhesive film to obtain a self-supporting metal mesh. S3. The self-supporting metal mesh is hot-pressed and transferred to the surface of a thermoplastic film layer or a viscoelastic film layer; S4. Place the thermoplastic or viscoelastic film layer with the metal mesh transferred between two transparent substrates, and complete the composite molding using a planar-curved integrated molding process or a curved direct embedding process to obtain a curved conformal transparent electromagnetic shielding structure. The integrated planar-curved surface molding process includes: sandwiching a thermoplastic film layer carrying a metal mesh between two planar transparent substrates, and simultaneously heating and pressurizing to complete the bonding, sealing and curved surface shaping, thereby realizing the integrated molding of the planar substrate into a curved surface; The curved surface direct embedding process includes: attaching a viscoelastic film layer carrying a metal mesh to the surface of a curved transparent substrate pre-coated with an adhesive, peeling off the viscoelastic film layer and curing the adhesive, so that the metal mesh is embedded in the surface layer of the curved transparent substrate.

[0013] Furthermore, the design steps for the metal mesh structure described in step S1 specifically include: Collect the stress distribution on the target surface and determine the strain requirements of each region; Adjust the angle, period, and arm length of the S-shaped structural unit to match the local tensile deformation capacity; Constructing a spiderweb-like main frame and filling it with an S-shaped mesh grid adapted to the strain creates a spiderweb-like S-shaped stretchable mesh with a gradual change in tensile strain from the center to the edge, which is the metal mesh grid structure.

[0014] Further, in step S2, the thickness of the conductive seed layer is 500 nm to 5 μm; the metal used for electrodeposition is any one or more alloys of copper, nickel, platinum, gold, silver, and tin.

[0015] Furthermore, in step S3, the hot pressing temperature is 80~120℃, and the hot pressing time is 1min~5min.

[0016] Furthermore, in step S4, the pressure of heating and pressurizing is 1MPa~50MPa, and the temperature is 100℃~150℃.

[0017] Furthermore, in the final conformal transparent electromagnetic shielding structure, the metal mesh is wrinkle-free, crack-free, and bubble-free, and the two layers of curved transparent substrates are completely sealed, resulting in a long service life.

[0018] According to specific embodiments provided by the present invention, the curved conformal transparent electromagnetic shielding structure and its manufacturing method disclosed by the present invention have the following technical effects: Excellent conformal performance: The biomimetic stepped strain S-shaped grid precisely matches the stress of the curved surface, and there are no wrinkles, buckling, or fractures caused by stress mismatch during the conformal process, making it suitable for complex curvature surfaces; Excellent and balanced performance: 1~15μm line width with stealth design, light transmittance ≥70%, sheet resistance ≤0.1Ω / sq, shielding efficiency ≥30dB, solving the industry problem of the incompatibility between high light transmittance and high shielding; Excellent uniformity: transmittance deviation in curved areas ≤10%, conductivity deviation ≤20%, grid period deviation ≤10%, and optical and electrical properties are uniform throughout the entire range; High durability: The metal mesh is embedded between two layers of plexiglass, making it scratch-resistant, anti-aging, and with a service life consistent with that of the optical substrate; Controllable process and low cost: No high vacuum deposition equipment is required, the process is highly compatible, it can be mass-produced, and it is also suitable for fields such as transparent antennas and transparent electric heating. Wide range of applications: The curved conformal metal mesh structure obtained by this invention can not only be used for transparent electromagnetic shielding, but also be extended to transparent antennas, transparent electric heaters and other fields. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the curved conformal transparent electromagnetic shielding structure of the present invention; Figure 2 This is the design process for the step-strain biomimetic spider web of the present invention; Figure 3 The present invention uses an S-shaped structure to control different tensile deformations; Figure 4 This is a design drawing of the stepped strain mesh structure of the present invention; Figure 5 Scanning electron microscope image of a cross-section of a grid structure; Figure 6 A planar scanning electron microscope image of a conformal metal mesh structure. Figure 7 This is a physical diagram of the curved conformal transparent electromagnetic shielding structure of the present invention; Explanation of reference numerals in the attached figures: 1. Curved transparent substrate; 2. Metal mesh; 3. Thermoplastic film layer. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] This invention designs a stretchable mesh structure mimicking a spider web, matching its tensile deformation to the stress distribution of a curved optical window. This solves problems such as buckling deformation and fracture caused by stress mismatch during the conformal process. Furthermore, by utilizing nanoimprinting, high-precision mesh peeling and transfer technology, and conformal fabrication technology, a high-performance conformal transparent electromagnetic shielding material with uniform mesh structure, uniform conductivity and light transmission, and no wrinkles or bubbles is achieved. This results in a conformal transparent electromagnetic shielding optical window with high light transmission, high conductivity, high shielding performance, and no optical distortion.

[0023] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0024] like Figure 1 As shown, the curved conformal transparent electromagnetic shielding structure provided by the present invention includes two layers of curved transparent substrate 1 and a biomimetic stepped strain stretchable metal mesh 2. The metal mesh 2 is embedded and encapsulated between two curved transparent substrates 1. The metal mesh 2 is a spiderweb-like S-shaped stretchable mesh that matches the stress distribution of the curved surface, and the tensile strain of the metal mesh 2 is gradually distributed in a stepped manner from the center to the edge of the curved surface. The metal mesh 2 has a narrow linewidth and a high aspect ratio structure. The shielding structure as a whole has high light transmittance, low sheet resistance, and high electromagnetic shielding efficiency, and the curved surface has uniform light transmittance and conductivity throughout.

[0025] The metal mesh has a line width of 1~15μm, an aspect ratio of not less than 1:1, and a mesh period deviation of not more than 10%; the overall light transmittance of the shielding structure is >70%, and the light transmittance deviation of the entire curved surface is within 10%; the sheet resistance of the shielding structure is ≤1Ω / sq, and the conductivity deviation of the entire curved surface is within 20%.

[0026] The metal mesh 2 is made of any one or more alloys of copper, nickel, platinum, gold, silver, and tin.

[0027] For example, a thermoplastic film layer 3 is also disposed between the two curved transparent substrates, and the metal mesh 2 is adhered to the curved transparent substrate through the thermoplastic film layer 3; the thermoplastic film layer 3 is one or more composites of PVB, PVA, TPU, PU, ​​and PE polymer thermoplastic materials.

[0028] The stretching deformation of the spiderweb-like S-shaped stretchable mesh is as follows: Figure 3 As shown in the figure, the key dimensional parameters constituting the S-shaped element are: the period T is the distance of the S-shaped periodic element structure, and the radius... r The radius and angle of the curved section of the S-shaped structure. α The arc angle of the curved section of the S-shaped structure, arm length l This refers to the distance along the curved endpoint of the S-shaped structure. This is achieved by adjusting the period T and the radius of the arc of the S-shaped element. r , arc angle α arm length l Four parameters allow for independent adjustment of the tensile deformation limit and mechanical adaptability of a single S-shaped unit, thereby matching the strain requirements of different regions of the curved surface.

[0029] This invention also provides a method for fabricating a curved conformal transparent electromagnetic shielding structure, applicable to the fabrication of the aforementioned curved conformal transparent electromagnetic shielding structure, comprising the following steps: S1, Step-Strain S-Shaped Mesh Structure Design: Design a step-strain metal mesh structure that matches the stress of the target surface. S2, Fabrication of a self-supporting stepped strain S-shaped grid structure: A nanoimprint mold with a corresponding pattern is prepared according to the designed metal grid structure. Then, a groove structure with the corresponding pattern is formed on the surface of a flexible substrate using the nanoimprint method. Next, a conductive seed layer with a thickness of 500nm-5μm is formed at the bottom of the groove using a scraping method. Then, a conductive metal material is formed using self-mask lithography and electrodeposition methods to obtain a metal grid structure with narrow linewidth and high aspect ratio. Finally, the metal grid structure in the groove is peeled off using a micro-adhesive film to obtain a self-supporting metal grid structure. S3, Conformal preparation of curved surfaces: First, the peeled self-supporting metal mesh structure is hot-pressed onto the surface of a thermoplastic film or a viscoelastic film. The hot-pressing temperature is 80-120℃ and the time is 1min-5min, so that the metal mesh is transferred to the surface of the thermoplastic film or the viscoelastic film. S4. Place the thermoplastic or viscoelastic film layer with the metal mesh transferred between two transparent substrates, and complete the composite molding using a planar-curved integrated molding process or a curved direct embedding process to obtain a curved conformal transparent electromagnetic shielding structure. The integrated planar-curved surface molding process includes: sandwiching a thermoplastic film layer carrying a metal mesh between two planar transparent substrates, and simultaneously completing the bonding, sealing and curved surface shaping by heating and pressurizing (pressure between 1MPa and 50MPa, temperature between 100 and 150℃) to achieve integrated molding of planar substrate into curved surface. The curved surface direct embedding process includes: attaching a viscoelastic film layer carrying a metal mesh to the surface of a curved transparent substrate pre-coated with an adhesive, peeling off the viscoelastic film layer and curing the adhesive, so that the metal mesh is embedded in the surface layer of the curved transparent substrate.

[0030] The final curved conformal transparent electromagnetic shielding material has a uniformly distributed metal mesh structure, a light transmittance of ≥70%, a sheet resistance of ≤1Ω / sq, a metal line width of 1-15μm, an aspect ratio of ≥1:1, a light transmittance variation of less than 10% across the entire curved surface, a sheet resistance of less than 20%, and a shielding efficiency of ≥30dB (300MHz-18GHz).

[0031] Among them, such as Figure 2 As shown, the design steps of the metal mesh structure in step S1 specifically include: firstly, determining the strain requirements of each region based on the stress distribution of the target curved surface, and adjusting the angle, period, and arm length of the S-shaped structural unit to match the local tensile deformation capacity (e.g., Figure 3 (As shown); then, design the main spider web structure to match the surface stress; next, fill the main structure with S-shaped mesh structures with corresponding tensile strengths; finally, design an S-shaped stretchable metal mesh structure with stepped tensile strain from the center to the edge, as shown. Figure 2 As shown.

[0032] Example: Transparent electromagnetic shielding structure for hemispherical curved optical windows This embodiment uses a thermoplastic film layer as an example to illustrate the fabrication process of a curved conformal transparent electromagnetic shielding structure: 1. S-shaped wire mesh structure design: The target surface is a hemispherical polycarbonate (PC) optical window with a diameter of 50 mm. First, the stress distribution on the hemispherical surface is calculated. The hemispherical surface is divided into 10 concentric ring regions from the central pole to the equator (e.g., ...). Figure 4 (As shown). The radial tensile strain in the central region (R0) is 0%, and the radial tensile strain in the edge region (region R9) is 220%. Accordingly, the radial period of the grid linearly varies from 150 μm in the central region to 88 μm in the edge region. The latitudinal tensile strain is 10% and remains constant. The basic linewidth of the S-shaped grid is designed to be 3 μm.

[0033] 2. Fabrication of self-supporting metal mesh: Nanoimprinting: A mold is fabricated based on the above design. A UV-curable nanoimprinting adhesive is coated on a flexible PET substrate, and the mold is used to imprint and cure the nanoimprint. After demolding, a groove pattern with a depth of approximately 4 μm is formed on the adhesive layer.

[0034] Seed layer filling: Nano silver conductive ink is scraped into the bottom of the groove using a doctor blade, and after heat treatment, a conductive seed layer with a thickness of 1-2 μm is formed.

[0035] Self-masking lithography and electroforming: Using the seed layer in the groove as an electrical connection and mask, a metal mesh structure with a depth linewidth of 3μm and a depth of 10μm is fabricated through self-masking lithography and electrodeposition technology.

[0036] Peeling: Using a polyacrylate micro-adhesive film as a support membrane, the copper mesh grid within the PET groove is completely peeled off, resulting in a self-supporting copper mesh grid structure. For example... Figure 5 As shown, the measured line width is 3.2 μm, the depth is 9.84 μm, and the aspect ratio is approximately 3:1.

[0037] 3. Conformal composite surfaces: First transfer: Lay the self-supporting copper mesh flat on the surface of the PVB (polyvinyl butyral) membrane material and hot press it for 2 minutes at 100℃ and 0.5MPa to embed and transfer the copper mesh to the surface of the PVB membrane.

[0038] Final lamination: The PVB film with copper mesh is sandwiched between two flat PMMA glass sheets, placed in a corresponding hemispherical mold, and then pressurized and heated (held at 120℃ and 10MPa for 30 minutes) to form a hemispherical curved surface. The height of the curved surface can be controlled by pressure. After cooling, it is removed. Figure 6 The exhibit showcases a conformal metal mesh structure.

[0039] 4. Performance Testing: The final hemispherical transparent electromagnetic shielding structure (such as...) is tested. Figure 7 (As shown) Perform the test: Optical performance: The transmittance of each region was tested using a spectrophotometer. The average transmittance was 84.2%, and the maximum deviation was 2.8% (<3%).

[0040] Electrical performance: The sheet resistance of each region was tested using the four-probe method. The average sheet resistance was 0.08Ω / sq, the standard deviation was 0.007Ω / sq, and the deviation was <10%.

[0041] Shielding effectiveness: According to the method tested in GJB 6190-2008, the shielding effectiveness is greater than 30dB in the 2GHz-10GHz frequency band.

[0042] Adhesion and scratch resistance: After cross-cut adhesion test and steel wool abrasion test, the performance remained unchanged, indicating that the mesh was firmly sealed.

[0043] In summary, the curved conformal transparent electromagnetic shielding structure and its manufacturing method provided by this invention have the following technical effects: 1. Design aspect: Based on the stress distribution of the curved surface, the present invention precisely controls the metal mesh structure so that its stress distribution corresponds to the curved substrate, so that buckling deformation or structural fracture will not occur due to stress mismatch during the conformal process of the curved surface, and achieves uniform light transmission and uniform conductivity.

[0044] 2. Structurally, the curved conformal transparent electromagnetic shielding material obtained by this invention has a narrow wire width, high aspect ratio, uniform period, no wrinkles, no buckling deformation, and no structural breakage. 3. Performance: It has high light transmittance (greater than 70%) and high conductivity (sheet resistance ≤ 1Ω / sq), and high electromagnetic shielding performance, solving the common industry problem that high light transmittance and high shielding performance cannot be achieved simultaneously in curved conformal transparent electromagnetic shielding materials.

[0045] 4. Strong scratch resistance and long service life: Because the metal mesh is sandwiched between two layers of acrylic glass, it has strong scratch resistance and a service life consistent with that of acrylic glass.

[0046] 5. Wide range of applications: It can be used not only in transparent electromagnetic shielding, but also in transparent antennas and transparent electric heating.

[0047] This document uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. Furthermore, those skilled in the art will recognize that, based on the ideas of the present invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A curved, conformal, transparent electromagnetic shielding structure, characterized in that, It includes two curved transparent substrates and a biomimetic stepped strain stretchable metal mesh. The metal mesh is embedded and encapsulated between two curved transparent substrates. The metal mesh is a spider web-like S-shaped stretchable mesh that matches the stress distribution of the curved surface, and the tensile strain of the metal mesh is gradually distributed in a stepped manner from the center to the edge of the curved surface. The metal mesh has a narrow linewidth and a high aspect ratio structure.

2. The curved conformal transparent electromagnetic shielding structure according to claim 1, characterized in that, The metal mesh has a line width of 1-15μm, an aspect ratio of not less than 1:1, and a mesh period deviation of not more than 10%. The overall light transmittance of the shielding structure is >70%, and the light transmittance deviation of the entire curved surface is within 10%; the sheet resistance of the shielding structure is ≤1Ω / sq, and the conductivity deviation of the entire curved surface is within 20%.

3. The curved conformal transparent electromagnetic shielding structure according to claim 1, characterized in that, The metal mesh is made of any one or more alloys of copper, nickel, platinum, gold, silver, and tin; the curved transparent substrate is made of plexiglass, polycarbonate, transparent resin, or inorganic glass.

4. The curved conformal transparent electromagnetic shielding structure according to claim 1, characterized in that, A thermoplastic film layer is also disposed between the two curved transparent substrates, and the metal mesh is adhered to the curved transparent substrate through the thermoplastic film layer; the thermoplastic film layer is one or more composites of PVB, PVA, TPU, PU, ​​and PE polymer thermoplastic materials.

5. A method for fabricating a curved conformal transparent electromagnetic shielding structure, applied to the fabrication of the curved conformal transparent electromagnetic shielding structure according to any one of claims 1-4, characterized in that, The steps include the following: S1. Based on the stress distribution data of the target surface, design a biomimetic stepped strain stretchable metal mesh structure that matches the tensile strain of the surface. S2. Based on the designed metal mesh structure, a nanoimprint mold is prepared. A high aspect ratio groove structure with corresponding pattern is formed on the surface of a flexible substrate by nanoimprinting. A conductive seed layer is prepared at the bottom of the groove. A conductive metal mesh is formed by self-mask photolithography and electrodeposition. Then, the metal mesh is peeled off using a micro-adhesive film to obtain a self-supporting metal mesh. S3. The self-supporting metal mesh is hot-pressed and transferred to the surface of a thermoplastic film layer or a viscoelastic film layer; S4. Place the thermoplastic or viscoelastic film layer with the metal mesh transferred between two transparent substrates, and complete the composite molding using a planar-curved integrated molding process or a curved direct embedding process to obtain a curved conformal transparent electromagnetic shielding structure. The integrated planar-curved surface molding process includes: sandwiching a thermoplastic film layer carrying a metal mesh between two planar transparent substrates, and simultaneously heating and pressurizing to complete the bonding, sealing and curved surface shaping, thereby realizing the integrated molding of the planar substrate into a curved surface; The curved surface direct embedding process includes: attaching a viscoelastic film layer carrying a metal mesh to the surface of a curved transparent substrate pre-coated with an adhesive, peeling off the viscoelastic film layer and curing the adhesive, so that the metal mesh is embedded in the surface layer of the curved transparent substrate.

6. The method for fabricating a curved conformal transparent electromagnetic shielding structure according to claim 5, characterized in that, The design steps for the metal mesh structure described in step S1 specifically include: Collect the stress distribution on the target surface and determine the strain requirements of each region; Adjust the angle, period, and arm length of the S-shaped structural unit to match the local tensile deformation capacity; Constructing a spiderweb-like main frame and filling it with an S-shaped mesh grid adapted to the strain creates a spiderweb-like S-shaped stretchable mesh with a gradual change in tensile strain from the center to the edge, which is the metal mesh grid structure.

7. The method for fabricating a curved conformal transparent electromagnetic shielding structure according to claim 5, characterized in that, In step S2, the thickness of the conductive seed layer is 500 nm to 5 μm; the metal used for electrodeposition is any one or more alloys of copper, nickel, platinum, gold, silver, and tin.

8. The method for manufacturing a curved conformal transparent electromagnetic shielding structure according to claim 5, characterized in that, In step S3, the hot pressing temperature is 80~120℃, and the hot pressing time is 1min~5min.

9. The method for manufacturing a curved conformal transparent electromagnetic shielding structure according to claim 5, characterized in that, In step S4, the pressure of heating and pressurizing is 1MPa~50MPa, and the temperature is 100℃~150℃.

10. The method for manufacturing a curved conformal transparent electromagnetic shielding structure according to claim 5, characterized in that, In the final conformal transparent electromagnetic shielding structure, the metal mesh is wrinkle-free, crack-free, and bubble-free, and the two layers of curved transparent substrates are completely sealed.

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