Flexible Ink-Minimized Screen-Printed Frequency Selective Surfaces With Increased Optical Transparency for 5G Electromagnetic Interference Mitigation
Daniel J. King, Khelifa Hettak, M. R. Chaharmir, Shulabh Gupta
Abstract
A thin, flexible, and transparent polyethylene terephthalate (PET) based screen-printed band-stop frequency selective surface (FSS) with ink minimization is experimentally demonstrated at 28 GHz using both planar and conformal configurations. A miniaturized conventional FSS unit cell is ink-minimized using surface meshing without compromising the angular stability of the transmission response of the surface within ±60°. This not only leads to reduced amount of expensive ink required in prototyping, thereby lowering the overall manufacturing cost, but also increases the optical transparency of the structure by a factor of 65% using an 80 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu \text{m}$ </tex-math></inline-formula> linewidth tolerance. Finally, the operation of the ink-minimized FSS is experimentally shown using a conformal geometry with two radii of curvature (60 and 114 mm) and a good filtering performance is confirmed. Useful for 5G electromagnetic interference (EMI) applications, these FSSs feature increased feasibility through improved transparency and reduced cost due to ink minimization.