Print Email Facebook Twitter High Accuracy Pointing for Quasi-optical THz Mixer Arrays Title High Accuracy Pointing for Quasi-optical THz Mixer Arrays Author Gasparsilva, Jose Rui (Rijksuniversiteit Groningen; SRON Netherlands Institute for Space Research) Finkel, M. (SRON Netherlands Institute for Space Research) Laauwen, Wouter (SRON Netherlands Institute for Space Research) Westerweld, Menno (SRON Netherlands Institute for Space Research) More, Nikhil (SRON Netherlands Institute for Space Research) Young, Abram (University of Arizona) Kulesa, Craig (University of Arizona) Walker, Christopher (University of Arizona) Van der Tak, Floris (Rijksuniversiteit Groningen; SRON Netherlands Institute for Space Research) Gao, J. (TU Delft ImPhys/Optics; SRON Netherlands Institute for Space Research) Date 2022 Abstract We report a high accuracy pointing technique for quasi-optical hot electron bolometer (HEB) mixers in focal-plane arrays designed to operate at 1.4, 1.9, and 4.7 THz. The high accuracy pointing is achieved by prealignment of a HEB chip to a lens, measuring the angular error of each mixer in an array assembly, and then realignment of the chip to the same lens to correct the error. The realigned mixers, using 5 mm diameter Si elliptical lenses designed for operation at 4.7 THz, show a final pointing error distribution with an average (μ) = 0.13° and standard deviation (σ) = 0.06°, with respect to the normal direction of the respective array plane. Those using 10 mm diameter lenses designed for operation either at 1.4 or 1.9 THz, show μ = 0.08° and σ = 0.03°. We demonstrated our pointing technique in five 4×2 HEB focal plane arrays developed for NASA's balloon borne GUSTO THz observatory. Our results corroborate the simulated beam steering factors used to calculate the realignment corrections. With the unprecedented pointing accuracy at the high frequencies, our technique can significantly facilitate the use of lens-antenna, quasi-optical mixers for future focal-plane arrays, which is able to compete with traditional feedhorn-waveguide mixer arrays, operated typically below 1 THz, for astronomical instrumentation. Subject Antenna arraysantenna radiation patternbeam steeringcryogeniclensesterahertz radiation To reference this document use: http://resolver.tudelft.nl/uuid:a4805693-e3a7-4cec-97d0-bd99598952bc DOI https://doi.org/10.1109/TTHZ.2021.3118607 ISSN 2156-342X Source IEEE Transactions on Terahertz Science and Technology, 12 (1), 53-62 Part of collection Institutional Repository Document type journal article Rights © 2022 Jose Rui Gasparsilva, M. Finkel, Wouter Laauwen, Menno Westerweld, Nikhil More, Abram Young, Craig Kulesa, Christopher Walker, Floris Van der Tak, J. Gao Files PDF High_Accuracy_Pointing_fo ... Arrays.pdf 1.65 MB Close viewer /islandora/object/uuid:a4805693-e3a7-4cec-97d0-bd99598952bc/datastream/OBJ/view