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Simulation and experimental studies are carried out on single‐layer and double‐layer embedded metal meshes (SLEMM and DLEMM) to assess their performance as transparent electromagnetic interference (EMI) shielding. The structures consist of silver meshes embedded in polyethylene terephthalate (PET). As a transparent electrode, SLEMMs exhibit a transparency of 82.7% and a sheet resistance of 0.61 Ωsq⁻¹as well as 91.0% and 1.49 Ωsq⁻¹. This performance corresponds to figures of merit of 3101 and 2620, respectively. The SLEMMs achieve 48.0 dB EMI shielding efficiency (SE) in the frequency range of 8–18 GHz (X‐ and Ku‐bands) with 91% visible transmission and 56.2 dB EMI SE with 82.7% visible transmission. Samples exhibit stable performance after 1000 bending cycles with a radius of curvature of 4 mm and 60 tape test cycles. DLEMMs consist of fabricating SLEMM on opposite sides of the substrate where the distance can be varied using a spacer. Simulations are performed to investigate how varying spacer distance between two layers of metal meshes influences the EMI SE. DLEMMs are fabricated and achieved an EMI SE of 77.7 dB with 81.7% visible transmission. SLEMMs and DLEMMs may have a wide variety of applications in aerospace, medical, and military applications.

 

The design of optical devices is a complex and time-consuming process. To simplify this process, we present a novel framework of multi-fidelity multi-objective Bayesian optimization with warm starts, called Multi-BOWS. This approach automatically discovers new nanophotonic structures by managing multiple competing objectives and utilizing multi-fidelity evaluations during the design process. We employ our Multi-BOWS method to design an optical device specifically for transparent electromagnetic shielding, a challenge that demands balancing visible light transparency and effective protection against electromagnetic waves. Our approach leverages the understanding that simulations with a coarser mesh grid are faster, albeit less accurate than those using a denser mesh grid. Unlike the earlier multi-fidelity multi-objective method, Multi-BOWS begins with faster, less accurate evaluations, which we refer to as “warm-starting,” before shifting to a dense mesh grid to increase accuracy. As a result, Multi-BOWS demonstrates 3.2–89.9% larger normalized area under the Pareto frontier, which measures a balance between transparency and shielding effectiveness, than low-fidelity only and high-fidelity only techniques for the nanophotonic structures studied in this work. Moreover, our method outperforms an existing multi-fidelity method by obtaining 0.5–10.3% larger normalized area under the Pareto frontier for the structures of interest.