3D printed diffractive terahertz lenses

[EN] A 3D printer was used to realize custom-made diffractive THz lenses. After testing several materials, phase binary lenses with periodic and aperiodic radial profiles were designed and constructed in polyamide material to work at 0.625 THz. The nonconventional focusing properties of such lenses were assessed by computing and measuring their axial point spread function (PSF). Our results demonstrate that inexpensive 3D printed THz diffractive lenses can be reliably used in focusing and imaging THz systems. Diffractive THz lenses with unprecedented features, such as extended depth of focus or bifocalization, have been demonstrated.Ministerio de Economia y Competitividad (MINECO) (FIS2011-23175); Generalitat Valenciana (PROMETEOII/2014/072); National Center for Research and Development in Poland (LIDER/020/319/L-5/13/NCBR/2014).Furlan, WD.; Ferrando Martín, V.; Monsoriu Serra, JA.; Zagrajek, P.; Czerwinska, E.; Szustakowski, M. (2016). 3D printed diffractive terahertz lenses. Optics Letters. 41(8):1748-1751. https://doi.org/10.1364/OL.41.001748S1748175141

3-D-Printed Flat Optics for THz Linear Scanners

THz beam shaping via a single diffractive optical element is used to convert a divergent beam into a focal line segment perpendicular to the optical axis. The novel structure was designed for narrowband applications as a kinoform element and we successfully applied it in active, high-speed, THz linear scanners. The theoretical approach and experimental results are presented

Comparison of terahertz technologies for detection and identification of explosives

We present results on the comparison of different THz technologies for the detection and identification of a variety of explosives from our laboratory tests that were carried out in the framework of NATO SET-193 “THz technology for stand-off detection of explosives: from laboratory spectroscopy to detection in the field” under the same controlled conditions. Several laser-pumped pulsed broadband THz time-domain spectroscopy (TDS) systems as well as one electronic frequency-modulated continuous wave (FMCW) device recorded THz spectra in transmission and/or reflection