Electromagnetic shielding optical window based on conductive mesh transfer and method of making the same
By using a conductive grid transfer method, the problems of high manufacturing cost and the influence of metal linewidth on light transmittance in optical window fabrication have been solved, achieving compatibility between high light transmittance and strong electromagnetic shielding, and making it suitable for both visible and infrared bands.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- GUANG XIAN YIN KE JI (NAN TONG) YOU XIAN GONG SI
- Filing Date
- 2022-09-22
- Publication Date
- 2026-06-02
Smart Images
Figure CN115413218B_ABST
Abstract
Description
Technical Field
[0001] This application belongs to the field of optical window technology, specifically relating to an electromagnetic shielding optical window based on conductive mesh transfer and its preparation method. Background Technology
[0002] The rapid development of electromagnetic technology has brought numerous conveniences to human life, but it has also made the space electromagnetic environment increasingly complex. To prevent electromagnetic interference and equipment malfunctions, the requirements for electromagnetic protection technology are becoming increasingly stringent. For example, in the field of visible or infrared optical windows, excellent optical performance is required, as well as strong electromagnetic shielding performance. This ensures that while personnel can observe information with their eyes or infrared detectors can acquire information, it is also necessary to prevent external electromagnetic wave signals such as cosmic rays, satellites, television, and radio from interfering with the internal working components of the system.
[0003] Transparent conductive films made of metal oxides, such as ITO, exhibit strong absorption in the infrared band and poor conductivity, making it impossible to achieve a balance between high transmittance and strong electromagnetic shielding in the infrared range. Currently, a widely used technique involves forming a metal mesh structure on a visible or infrared optical window. The unique perforated nature of the metal mesh allows for high transmittance and conductivity across a wide wavelength range. Existing techniques typically employ electron beam deposition combined with etching processes to fabricate the metal mesh structure on the optical window; however, this method is costly and requires a high-vacuum environment. Existing techniques also utilize electric field-driven 3D printing to obtain metal mesh structures on substrates, but this method produces metal linewidths that are visible to the naked eye, affecting transmittance. Summary of the Invention
[0004] The purpose of this application is to provide an electromagnetic shielding optical window based on conductive mesh transfer and its preparation method, so as to solve the technical problems of high cost of the preparation process of metal mesh on optical windows in the prior art, the need for a high vacuum environment, and the wide, visible metal linewidth that affects light transmittance.
[0005] To achieve the above objectives, one technical solution adopted in this application is:
[0006] A method for fabricating an electromagnetic shielding optical window based on conductive mesh transfer is provided, comprising:
[0007] A substrate is provided, wherein the substrate has a grooved grid structure;
[0008] A conductive mesh is formed within the grooved mesh structure;
[0009] The conductive mesh is transferred from the substrate to the transfer film;
[0010] The conductive mesh is transferred from the transfer film to the surface of the optical window and fixed to obtain an electromagnetic shielding optical window.
[0011] In one or more embodiments, the step of transferring the conductive mesh from the substrate to the transfer film includes:
[0012] The substrate is folded around;
[0013] The substrate is placed on the surface of the transfer film, so that the conductive mesh comes into contact with the transfer film;
[0014] The substrate and the transfer film are pressed together to adhere the conductive mesh to the transfer film, and then the substrate is peeled off.
[0015] In one or more embodiments, the step of transferring the conductive mesh from the transfer film to the optical window surface and fixing it includes:
[0016] An adhesive layer is provided on the surface of the optical window;
[0017] The transfer film is placed on the surface of the optical window, so that the conductive mesh is in contact with the adhesive layer;
[0018] Hot pressing causes the conductive mesh to adhere to the adhesive layer, and the transfer film is then removed.
[0019] In one or more embodiments, the step of setting the adhesive layer on the optical window surface specifically involves forming the adhesive on the optical window surface using spin coating, spraying, or printing methods.
[0020] In one or more embodiments, the thickness of the adhesive layer is 50 nm to 5 μm, and the material of the adhesive layer includes one or more combinations of PVB, PVB, PVA, PET, PU, TPU and two-component epoxy resin.
[0021] In one or more embodiments, the hot pressing causes the conductive mesh to adhere to the adhesive layer, and after the step of peeling off the transfer film, the method further includes:
[0022] Remove the portion of the adhesive layer corresponding to the cutout of the conductive mesh to expose the optical window.
[0023] In one or more embodiments, the step of removing the portion of the adhesive layer corresponding to the cutout of the conductive mesh specifically involves using an etching process to remove the portion of the adhesive layer corresponding to the cutout of the conductive mesh. The etching process includes one or more combinations of plasma etching, solution etching, Pyrelin dielectric etching, and ICP etching.
[0024] In one or more embodiments, the transfer membrane is a polymer film, and the transfer membrane is a PU film, PI film, PET film, TPU film or PVB film.
[0025] To achieve the above objectives, another technical solution adopted in this application is:
[0026] An electromagnetic shielding optical window prepared by the preparation method described in any of the above embodiments is provided.
[0027] In one or more embodiments, the conductive grid of the electromagnetic shielding optical window has a linewidth of 2 to 10 μm and an aspect ratio of 1:2 to 2:1. The electromagnetic shielding optical window has a transmittance of 20 to 90% in the 100 nm-14 μm band, a sheet resistance of 0.01 to 10 Ω / cube, and a shielding efficiency of 10 to 100 dB in the 300 MHz-40 GHz band.
[0028] The advantages of this application, which differ from existing technologies, are:
[0029] The preparation method of this application adopts the method of first preparing a conductive mesh and then transferring the conductive mesh to the optical window substrate for bonding to prepare an electromagnetic shielding optical window. This method effectively avoids processes such as etching and vapor deposition on the optical window, and can be fabricated on a large area, effectively reducing the manufacturing cost and simplifying the process. At the same time, the material of the optical window substrate is not limited, has strong compatibility, and has a wide range of applications, which can meet the transparent electromagnetic shielding requirements of different application scenarios.
[0030] The preparation method of this application uses a substrate with a grooved grid structure. The conductive grid is prepared by setting conductive material in the grooved grid structure. The preparation method is simple and efficient. The line width and sheet resistance of the conductive grid can be freely designed according to the requirements to obtain a conductive grid with fine line width and high aspect ratio, which effectively ensures the light transmittance and electromagnetic shielding performance of the optical window.
[0031] The preparation method of this application first transfers the conductive mesh from the substrate to the intermediate film, and then transfers it from the intermediate film to the optical window for fixation. The design is ingenious, the operation is efficient, and the process is simple.
[0032] The material of the optical window substrate of the electromagnetic shielding optical window of this application is not limited, has strong compatibility, and has a wide range of applications, which can meet the transparent electromagnetic shielding requirements of different application scenarios.
[0033] The electromagnetic shielding optical window of this application has a transmittance of 20-90% in the 100nm-14μm band, a sheet resistance of 0.01-10Ω / cube, and a shielding efficiency of 10-100dB in the 300MHz-40GHz band, which can ensure both transmittance and electromagnetic shielding effect.
[0034] The conductive grid of the electromagnetic shielding optical window of this application has a line width of 2 to 10 μm and an aspect ratio of 1:2 to 2:1. The fine line width and high aspect ratio can effectively improve the light transmittance of the optical window while ensuring its electromagnetic shielding performance. Attached Figure Description
[0035] Figure 1 This is a flowchart illustrating one embodiment of the method for fabricating an electromagnetic shielding optical window based on conductive mesh transfer, as described in this application.
[0036] Figure 2 This is a schematic diagram of the structure of one embodiment of the substrate of this application;
[0037] Figure 3 This application Figure 1 A structural diagram of the state corresponding to step S200;
[0038] Figure 4 yes Figure 1 A flowchart of one embodiment corresponding to step S300;
[0039] Figure 5 yes Figure 4 A structural diagram of the state corresponding to step S303 in the middle step;
[0040] Figure 6 yes Figure 1 A flowchart of one embodiment corresponding to step S400;
[0041] Figure 7 yes Figure 6 A structural diagram of the state corresponding to step S401;
[0042] Figure 8 yes Figure 6 A structural diagram of the state corresponding to step S402 in the middle section;
[0043] Figure 9 yes Figure 6 A structural diagram of the state corresponding to step S403 in the middle section;
[0044] Figure 10 This is a schematic diagram of one embodiment of the electromagnetic shielding optical window based on conductive mesh transfer in this application;
[0045] Figure 11 This is a schematic diagram of the substrate structure of Embodiment 1 of this application;
[0046] Figure 12 This is a schematic diagram of the substrate structure of Embodiment 2 of this application. Detailed Implementation
[0047] The present application will now be described in detail with reference to the embodiments shown in the accompanying drawings. However, these embodiments do not limit the present application, and any structural, methodological, or functional modifications made by those skilled in the art based on these embodiments are included within the protection scope of the present application.
[0048] Currently, the requirements for electromagnetic protection technology for various devices are becoming increasingly stringent. For example, in the field of visible or infrared optical windows, both excellent optical performance and strong electromagnetic shielding performance are required. While ensuring the observation of information by the human eye or the acquisition of information by infrared detectors, it is also necessary to prevent external electromagnetic wave signals such as cosmic rays, satellites, television, and radio from interfering with the internal working components of the system.
[0049] Transparent electromagnetic shielding materials used for optical windows mainly include ITO metal oxide. However, ITO has strong absorption in the infrared band and poor conductivity, making it impossible to achieve compatibility between high light transmittance and strong electromagnetic shielding in the infrared band. In addition, it is costly.
[0050] To achieve a balance between high transmittance in the infrared band and strong electromagnetic shielding, another approach is to form a metal mesh structure on a visible or infrared optical window. The unique perforated nature of the metal mesh allows it to exhibit high transmittance and conductivity over a wide wavelength range. However, current technologies employ electron beam deposition or electric field-driven 3D printing to obtain the metal mesh structure on the substrate. The former is too costly and requires a high vacuum environment, while the latter results in a wider, visible metal linewidth that affects transmittance.
[0051] To address the aforementioned issues, the applicant provides an electromagnetic shielding optical window based on conductive mesh transfer and its fabrication method. This method employs a pre-fabricated conductive mesh followed by a composite of the conductive mesh and the optical window, achieving compatibility between high light transmittance and strong electromagnetic shielding in both visible and infrared bands, while effectively reducing the fabrication cost and manufacturing steps of the optical window.
[0052] Specifically, please refer to Figure 1 , Figure 1 This is a schematic flowchart of one embodiment of the method for preparing an electromagnetic shielding optical window based on conductive mesh transfer according to this application.
[0053] The method includes:
[0054] S100, provides a substrate.
[0055] Specifically, the substrate 1 is provided with a grooved grid structure 2, please refer to [reference needed]. Figure 2 , Figure 2 This is a schematic diagram of the structure of one embodiment of the substrate of this application.
[0056] The grooved mesh structure 2 on the substrate 1 matches the conductive mesh to be fabricated, thus enabling the rapid fabrication of the conductive mesh using this grooved mesh structure 2. The groove width and depth of the grooved mesh structure 2 can be determined based on the required linewidth and thickness of the conductive mesh.
[0057] S200, A conductive mesh is formed within the grooved mesh structure.
[0058] Please see Figure 3 , Figure 3 This application Figure 1 A schematic diagram of the structure corresponding to step S200. By placing conductive material in the grooves of the grooved mesh structure 2, conductive mesh 3 can be quickly prepared, and the line width can be freely designed. This allows for the production of conductive meshes with a line width of less than 5 μm and an aspect ratio of less than 2:1, effectively improving light transmittance and conductivity, enhancing visual effects and shielding efficiency.
[0059] The form and material of the conductive mesh 3 can be freely selected. The conductive mesh 3 can be composed of bulk metal, or it can be composed of conductive polymers, metal nanoparticles, carbon materials, etc., or it can be composed of a combination of the above materials. As long as good conductivity can be achieved, the effect of this embodiment can be achieved.
[0060] In one application scenario, a conductive mesh can be prepared by scraping conductive material into the grooved mesh structure 2. In other application scenarios, conductive material can also be set in the grooved mesh structure 2 by spraying, printing or electrodeposition to form a conductive mesh 3, all of which can achieve the effect of this embodiment.
[0061] S300: Transfer the conductive mesh from the substrate to the transfer film.
[0062] After the conductive mesh 3 is prepared, it is peeled off from the substrate 1 and transferred to the transfer film 4, which helps the subsequent bonding of the conductive mesh 3 with the optical window.
[0063] For details, please refer to Figure 4 , Figure 4 yes Figure 1 A flowchart of one embodiment corresponding to step S300.
[0064] Methods for transferring conductive meshes from a substrate to a transfer film include:
[0065] S301, Perform a folding operation on the substrate.
[0066] The purpose of folding the substrate 1 is to reduce the adhesion between the conductive mesh and the substrate. To ensure the effectiveness of the folding operation, the substrate is preferably a flexible substrate, such as a PET substrate.
[0067] In one application scenario, a roller with a diameter of 1 to 10 mm can be used to fold the substrate 1. In other application scenarios, other devices can also be used to fold the substrate 1, and the effects of this embodiment can be achieved.
[0068] S302. Place the substrate on the surface of the transfer film so that the conductive mesh comes into contact with the transfer film.
[0069] S303, press the substrate and transfer film together to bond the conductive mesh to the transfer film, and then peel off the substrate.
[0070] Please see Figure 5 , Figure 5 yes Figure 4 A structural diagram of the state corresponding to step S303.
[0071] After the substrate 1 is folded, it can be placed on the surface of the transfer film 4 so that the conductive mesh 3 comes into contact with the transfer film 4. Then, it is pressed together to improve the adhesion between the conductive mesh 3 and the transfer film 4, while further reducing the adhesion between the conductive mesh 3 and the substrate 1.
[0072] To ensure adhesion between the conductive mesh 1 and the transfer film 4, the transfer film 4 can be a polymer film. In one application scenario, the transfer film 4 can specifically be a polyurethane (PU) film. In other application scenarios, the transfer film 4 can also be a polyimide (PI) film, a polyethylene terephthalate (PET) film, a thermoplastic polyurethane rubber (TPU) film, or a polyvinyl butyral (PVB) film, all of which can achieve the effect of this embodiment.
[0073] S400: The conductive mesh is transferred from the transfer film to the surface of the optical window and fixed to obtain the electromagnetic shielding optical window.
[0074] After the conductive mesh 3 is transferred onto the transfer film 4, it can be fully exposed, which helps to fix the conductive mesh 3 to the optical window 5.
[0075] Specifically, please refer to Figure 6 , Figure 6 yes Figure 1 A flowchart of one embodiment corresponding to step S400.
[0076] Methods for transferring conductive mesh from the transfer film to the optical window surface and fixing it include:
[0077] S401. An adhesive layer is provided on the surface of the optical window.
[0078] First, apply adhesive 6 for bonding the conductive mesh onto the optical window 5. (See [link to relevant documentation]). Figure 7 Figure 7 is Figure 6 A structural diagram of the state corresponding to step S401.
[0079] To ensure adhesion and prevent excessive adhesive from overflowing during bonding and affecting the optical effect of the optical window, the adhesive layer 6 should be relatively thin, for example, the thickness of the adhesive layer 6 can be selected as 50nm to 5μm.
[0080] In one application scenario, in order to reduce the thickness of the adhesive layer 6, the adhesive layer 6 can be formed by spin coating. In other application scenarios, the adhesive layer can also be formed by spraying or printing, and both methods can achieve the effect of this embodiment.
[0081] To ensure the adhesion of the conductive mesh 3, the adhesive can optionally be one or a combination of materials such as PVB, polyvinyl alcohol PVA, PET, PU, TPU, and two-component epoxy resin, all of which can achieve the effect of this embodiment.
[0082] S402. Place the transfer film on the surface of the optical window so that the conductive mesh comes into contact with the adhesive layer.
[0083] Please see Figure 8 , Figure 8 yes Figure 6 A structural diagram of the state corresponding to step S402.
[0084] S403. Hot pressing causes the conductive mesh to adhere to the adhesive layer, and the transfer film is then removed.
[0085] After placing the transfer film 4 on the optical window 5, hot-pressing the transfer film 4 effectively improves the adhesion between the conductive mesh 3 and the adhesive layer 6. Then, peeling off the transfer film 4 transfers the conductive mesh 3 onto the optical window 5, thus creating an optical window that simultaneously ensures high light transmittance and electromagnetic shielding. (See also...) Figure 9 , Figure 9 yes Figure 6 A structural diagram of the state corresponding to step S403.
[0086] The temperature and time of hot pressing can be selected according to the actual working conditions. For example, when the transfer film 4 is a PVB film and the adhesive layer 6 is made of PVB material, the hot pressing temperature can be 100℃ and the hot pressing time can be 5 minutes to transfer the conductive mesh onto the optical window; when the transfer film 4 is a PET film and the adhesive layer 6 is made of PU material, the hot pressing temperature can be 120℃ and the hot pressing time can be 10 minutes to transfer the conductive mesh onto the optical window.
[0087] In one application scenario, a heated roller can be used to press the transfer film 4 to accelerate the adhesion between the conductive mesh 3 and the adhesive layer 6, and simultaneously accelerate the separation of the conductive mesh 3 from the transfer film 4. The temperature of the heated roller can be selected according to the actual working conditions. For example, for the PET material transfer film 4, it can be hot-pressed multiple times with a roller at 70-150℃ to make the conductive mesh detach from the transfer film 4 and adhere to the optical window 5.
[0088] It is understood that the material of the optical window in the preparation method of this application is not limited and can be selected according to the specific application scenario of the product. For example, when applied to the 380nm-800nm band, ordinary silicate glass can be used as the optical window; when applied to the 100nm-4μm band, sapphire substrate can be used as the optical window; when applied to the 7μm-14μm band, germanium glass can be used as the optical window, etc. All of these can achieve the effect of this embodiment, thereby effectively improving the application range of electromagnetic shielding optical windows.
[0089] In one embodiment, in applications where the light transmittance of the optical window is critical, to further improve the light transmittance of the optical window, the step S400 above further includes:
[0090] Remove the portion of the adhesive layer corresponding to the cutouts in the conductive mesh to expose the optical window.
[0091] Understandably, since the adhesive layer 6 is fully coated on the surface of the optical window 5, when the conductive mesh 3 is combined with the optical window 5, the adhesive layer corresponding to the cutouts of the conductive mesh 3 will be exposed, which will affect the light transmittance of the optical window to some extent.
[0092] Therefore, the light transmittance can be further improved by removing a portion of the adhesive layer corresponding to the cutouts in the conductive mesh 3.
[0093] Specifically, the above-mentioned method for removing the adhesive layer 6 can employ an etching process. In one application scenario, the exposed adhesive layer 6 can be etched away using plasma etching to expose the optical window; in other application scenarios, etching methods such as solution etching, Piriton etching, and ICP etching can also be used to etch away the exposed adhesive layer 6, all of which can achieve the effect of this embodiment.
[0094] This application also provides an electromagnetic shielding optical window based on conductive mesh transfer, prepared using the above-described method. Please refer to [link to relevant documentation]. Figure 10 , Figure 10 This is a schematic diagram of one embodiment of the electromagnetic shielding optical window based on conductive mesh transfer in this application.
[0095] The electromagnetic shielding optical window includes an optical window 5 and a conductive mesh 3 bonded and fixed to the surface of the optical window 5. An adhesive layer 6 is provided between the conductive mesh 3 and the optical window 5.
[0096] In one embodiment, the conductive grid of the electromagnetic shielding optical window has a line width of 2 to 10 μm and an aspect ratio of 1:2 to 2:1.
[0097] The electromagnetic shielding optical window has a transmittance of 20-90% in the 100nm-14μm band, a sheet resistance of 0.01-10Ω / cube, and a shielding efficiency of 10-100dB in the 300MHz-40GHz band.
[0098] The present application will now be described in detail with reference to specific embodiments.
[0099] Example 1:
[0100] An electromagnetic shielding optical window based on conductive mesh transfer is fabricated using the following steps:
[0101] 1. Provide a substrate 1, such as Figure 11 As shown, the substrate 1 is a PET substrate, and the surface of the substrate 1 is provided with a hexagonal grid groove structure 2, with a groove line width of 3μm, a groove depth of 4μm, and a grid period of 100μm;
[0102] 2. A 1μm thick layer of silver nanoparticles is formed in the grooved grid structure 2 of the substrate 1 by a scraping method. Then, metallic copper is deposited on the surface of the silver nanoparticle layer by an electrodeposition method until the grooved grid structure is completely filled and protrudes 2μm from the groove, forming a silver and copper composite metal grid.
[0103] 3. Use a 10mm diameter roller to fold the substrate 1 once. After folding once, place the substrate 1 on the surface of the PU film and make the metal mesh fully contact the PU film. Remove the substrate 1 and transfer the metal mesh to the surface of the PU film.
[0104] 4. Spin a 300nm thick PVB adhesive layer on the quartz glass surface, place the PVB film on the quartz glass surface, and make the metal mesh contact the PVB adhesive layer.
[0105] 5. Press the PU film at 100℃ for 5 minutes, peel off the PU film, and bond the metal mesh to the surface of the quartz glass to form a transparent electromagnetic shielding optical window with high light transmittance that integrates metal mesh and quartz glass.
[0106] The optical window prepared in Example 1 was tested and found that it has a transmittance of more than 80% and a sheet resistance as low as 0.5Ω / cube in the 200nm-3300nm wavelength range. The electromagnetic shielding efficiency in the X-band reaches more than 20dB. It can achieve both high transmittance and high electromagnetic shielding effect in a wide wavelength range including visible light.
[0107] Example 2:
[0108] An electromagnetic shielding optical window based on conductive mesh transfer is fabricated using the following steps:
[0109] 1. Provide a substrate 1, such as Figure 12 As shown, the substrate 1 is a PET substrate, and the surface of the substrate 1 is provided with a square grid groove structure 2, with a groove line width of 5μm, a groove depth of 8μm, and a grid period of 200μm;
[0110] 2. A copper particle layer is formed in the grooved grid structure 2 of the substrate 1 by a scraping method, and then an 8μm thick nickel metal layer is formed on the surface of the copper particles by an electrodeposition method, forming a copper / nickel composite metal grid.
[0111] 3. Use a roller with a diameter of 5mm to fold the substrate 1 three times. Then place the substrate 1 on the surface of the PET film and make the metal mesh fully contact the PET film.
[0112] 4. Spin-coat a 1μm thick PU adhesive layer onto the surface of the germanium sheet, place the PET film on the surface of the germanium sheet, and make the metal mesh contact the PU adhesive layer;
[0113] 5. Press the PET film at 120℃ for 10 minutes, peel off the PET film, and then bond and fix the metal mesh to the surface of the germanium sheet.
[0114] 6. The adhesive layer and the corresponding part of the conductive mesh are removed by plasma etching to expose the germanium wafer. The etching power is 600W and the etching time is 5min to form an infrared transparent electromagnetic shielding optical window that integrates a metal mesh and germanium wafer with high light transmittance.
[0115] The optical window of this embodiment was tested. The optical window prepared in this embodiment has a transmittance of more than 60% in the 7μm-14μm band, a sheet resistance of 0.1Ω / block, and an electromagnetic shielding efficiency of more than 40dB in the X-band. It can achieve high transmittance and high electromagnetic shielding effect in the infrared band.
[0116] The foregoing description of this disclosure is provided to enable any person skilled in the art to implement or use this disclosure. Various modifications to this disclosure will be apparent to those skilled in the art, and the general principles applicable herein can be applied to other variations without departing from the scope of this disclosure. Therefore, this disclosure is not limited to the examples and designs described herein, but is consistent with the widest scope of the principles and novel features disclosed herein.
Claims
1. A method for fabricating an electromagnetic shielding optical window based on conductive mesh transfer, characterized in that, include: A substrate is provided, wherein the substrate has a grooved grid structure; A conductive mesh is formed within the grooved mesh structure; wherein, a conductive material is placed within the grooves of the grooved mesh structure to prepare a conductive mesh with a linewidth of less than 5 μm and an aspect ratio of less than 2:
1. The conductive mesh is transferred from the substrate to the transfer film; The conductive mesh is transferred from the transfer film to the surface of the optical window and fixed to obtain an electromagnetic shielding optical window. The step of transferring the conductive mesh from the substrate to the transfer film includes: The substrate is folded around; The substrate is placed on the surface of the transfer film, so that the conductive mesh comes into contact with the transfer film; The substrate and the transfer film are pressed together to adhere the conductive mesh to the transfer film, and then the substrate is peeled off. The step of transferring the conductive mesh from the transfer film to the optical window surface and fixing it includes: An adhesive layer is disposed on the surface of the optical window, and the thickness of the adhesive layer is 50 nm to 5 μm. The transfer film is placed on the surface of the optical window, so that the conductive mesh is in contact with the adhesive layer; Hot pressing causes the conductive mesh to adhere to the adhesive layer, and the transfer film is then removed; Remove the portion of the adhesive layer corresponding to the cutout of the conductive mesh to expose the optical window; Specifically, the step of removing the portion of the adhesive layer corresponding to the cutout of the conductive mesh involves using an etching process to remove the portion of the adhesive layer corresponding to the cutout of the conductive mesh. The etching process includes one or more combinations of plasma etching, solution etching, Parelin dielectric etching, and ICP etching.
2. The preparation method according to claim 1, characterized in that, The step of setting an adhesive layer on the surface of the optical window specifically involves forming the adhesive on the surface of the optical window using spin coating, spraying, or printing methods.
3. The preparation method according to claim 1, characterized in that, The adhesive layer has a thickness of 50nm-5μm, and the material of the adhesive layer includes one or a combination of PVB, PVB, PVA, PET, PU, TPU and two-component epoxy resin.
4. The preparation method according to claim 1, characterized in that, The transfer membrane is a polymer film, and the transfer membrane is a PU film, PI film, PET film, TPU film or PVB film.
5. An electromagnetic shielding optical window prepared by any one of the preparation methods described in claims 1 to 4.
6. The electromagnetic shielding optical window according to claim 5, characterized in that, The conductive grid of the electromagnetic shielding optical window has a linewidth of 2–10 μm and an aspect ratio of 1:2–2:
1. The electromagnetic shielding optical window has a transmittance of 20–90% in the 100nm–14μm wavelength range, a sheet resistance of 0.01–10 Ω / cube, and a shielding efficiency of 10–100 dB in the 300MHz–40GHz frequency band.