Fabrication of functional hollow waveguide devices for electromagnetic waves in 200–400GHz band using UV-curable resin type 3D printer, RECILS

We fabricated functional hollow waveguide (WG) devices, specifically straight waveguides (WGs), bandpass filter (BPF) WGs and twisted WGs, for electromagnetic waves at 200–400 GHz using our UV-curable resin type 3D printer, RECILS together with metal plating. These devices mainly comprise 25.4-mm-long hollow structures with a cross section of 0.86×0.43mm^2. RECILS is featured by its ability to produce palm-sized objects with a high resolution (20-30 µm) at high speed (100 cm^3/hour). The confinement of electromagnetic waves is realized by forming a copper layer plated on surfaces of hollow structures. BPF WGs consist of 5 coupled cavities formed in a WG. Twisted WGs are composed of a waveguide in which a 6-mm region of a WG is twisted by 90 degrees. These functional WG devices exhibit performance comparable to that of bulk metal WGs. This technology can fabricate THz WG devices with arbitrarily shapes in a short time at low cost.