Breaking the Aperture Limit: Interference‐Enhanced Stacking and Constraint‐Driven Design of Metallic Meshes

Achieving high optical transmittance and shielding effectiveness (SE) remains challenging for transparent electromagnetic interference (EMI) shielding materials. Herein, a physics‐guided, constraint‐driven design strategy for metallic meshes is developed through electromagnetic simulations, machine learning, and experiments. Single‐layer SE approaches saturation with increasing conductivity at a level set by the mesh geometry, dominated by the period, while the conductivity required for saturation decreases with increasing conductor cross‐section. At a fixed cross‐sectional area, a narrow‐and‐high cross‐section (w < t) improves both SE and transmittance relative to a square one. Interference‐enhanced stacking allows double‐ and triple‐layer SE to reach approximately 2.17 and 3.40 times the single‐layer value expressed in dB, respectively, with equal metal allocation maximizing SE under a fixed metal budget. XGBR and response‐surface models enable rapid screening of structures that meet prescribed SE requirements while balancing transmittance, total interlayer spacing, and metal cross‐sectional area. The selected triple‐layer design achieves 88% transmittance, 10.86% haze, and an average experimental SE of 92.17 dB in the X‐band, and its assembly tolerance and conductivity sensitivity are further analyzed. This strategy links quantitative electromagnetic analysis with requirement‐driven design of transparent metallic meshes.