Optical Characterisation of Stereolithography-Printed Composites for THz Quasi-Optical Applications

This work investigates the potential of filler materials to enhance the THz transparency of photopolymers compatible with the stereolithography (SLA) 3D printing process. Photopolymers filled with PTFE (~ 30% wt.) and silica (~ 66% wt.) were fabricated via SLA and characterised using a THz time-domain spectroscopy system (THz-TDS). The THz-TDS measurements revealed absorption coefficients of 15.3 cm ‾¹ and 11.7 cm ‾¹ at 1 THz for the PTFE and Silica composites, respectively, with the latter showing a 44.8 % reduction compared with conventional AM photopolymers at the same frequency. This work highlights the potential of filled-photopolymer composites to enable the manufacture of more efficient quasi-optical components via SLA.