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arXiv · 1803.07894

3D-Printed Phase Waveplates for THz Beam Shaping

Abstract

The advancement of 3D-printing opens up a new way of constructing affordable custom terahertz (THz) components due to suitable printing resolution and THz transparency of polymer materials. We present a way of calculating, designing and fabricating a THz waveplate that phase-modulates an incident THz beam (λ=2.14 mm) in order to create a predefined intensity profile of the optical wavefront on a distant image plane. Our calculations were performed for two distinct target intensities with the use of a modified Gerchberg-Saxton algorithm. The resulting phase-modulating profiles were used to model the polyactide elements, which were printed out with a commercially available 3D-printer. The results were tested in an THz experimental setup equipped with a scanning option and they showed good agreement with theoretical predictions.

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Jan Gospodaric, Artem Kuzmenko, Anna Pimenov, Christian Huber, Dieter Suess, Stefan Rotter, Andrei Pimenov. 2018-03-21. 3D-Printed Phase Waveplates for THz Beam Shaping. https://doi.org/10.1063/1.5027179

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