Microwave Characterization of 3D Printed Layers with a Fabry-Perot Open Resonator

3D-printed materials made of a liquid photocurable resin using a gyroid latticing technology are characterized in the frequency range spanning from 1.9 up to 110 GHz using split-post dielectric resonators and a Fabry-Perot open resonator. It is shown that such materials can be low-loss in a broad frequency range if appropriate settings of the lattice are employed. Presented measurements confirm theoretical predictions that such lattice structures exhibit an upper cut-off frequency due to a lateral mode occurring in the structure, which mainly depends on the unit cell size. Another novel experimental finding is that the investigated materials exhibit inplane anisotropy, typical for inhomogeneous structures. The proposed measurement methods provides a unique insight into electromagnetic properties of such 3D-printed materials, thus, enabling their further optimisation for the use at even higher frequencies.