3d printed optical components for thz-spectroscopy

In this thesis, the possibility of manufacturing Terahertz (THz) optical components using the 3D printing technology is discussed through different aspects. The material selection is depending on two factors: the materials printability and the materials fingerprint at the THz region 0.1-10 THz. These factors were found in acrylic photo polymers printable with the PolyJet technology, which also gives sufficient layer resolution of 16 m. From the “Vero material family”, the VeroClear photopolymer with 1.1 cm-1 absorption coefficient was chosen to fabricate THz optical components at 0.14 THz. The following THz components were fabricated: Simple lenses including bi-convex and plano-convex lenses, axicons with 5 and 11 base angles, spiral phase plates with one and two steps, and helical axicons with 5 base angle including one and two steps, and 11 base angle including one and two steps. To reach the optimal design for the optical components, a ray tracing simulation was performed in the software ZEMAX. Then the simulated optical components were converted to physical models by 3D printing using PolyJet technology. The 3D printed THz optical components were characterized using a 0.14 THz sub-Gaussian source and a 32x32 pixels detector. These optical components were used to generate Gaussian beams, Laguerre Gaussian beams and Bessel beams with zero, first and second orders. The focus was given on the Bessel beams as they are commonly used in optics because of their special features to be non-diffractive and self-healing, and because they have a lot of potential for THz applications as well.submitted by Malak Ahmad, BSc.Universität Linz, Masterarbeit, 2019(VLID)363783