Lightweight Deployable Millimeter-Wave MetaLens: Structural Analysis and Precision Fabrication

Here we advance lightweight deployable structural solutions for transmission-based radio-frequency (RF) apertures called MetaLenses, which consist of a 3D lattice of conductive meta-particles. In this work, the 3D lattice of meta-particles is supported by 22 parallel tensioned membrane layers, separated by 0.3 mm. We demonstrate through full-scale physical experiments the feasibility of constructing a 1.6 m x 0.4 m MetaLens module consisting of tensioned polyimide membranes, where the desired in-plane layer-to-layer alignment accuracy is better than 30~microns. This extreme precision is necessitated by the millimeter-scale RF wavelengths under consideration. We use active metrology and precision position adjustment during fabrication, along with heat-activated adhesives, for this demonstration. Additionally, we use finite element structural analysis to demonstrate that the deployed MetaLens can be made sufficiently stiff, and investigate sensitivity of the deployed natural frequencies of structural vibration to various design parameters.