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PUBLICATIONS

Pulsed terahertz bi-directional reflection distribution function (BRDF) measurements of materials and obscurants

Published

Author(s)

Shu Z. Lo, David R. Novotny, Erich N. Grossman, Edwin J. Heilweil

Abstract

A pulsed terahertz imaging system modified to perform angular detection of light for quantitatively characterizing reflection and scattering from samples is reported. Reflection from a gold mirror shows that the full width half maximum (FWHM) of the terahertz beam angular spread is <1° with signal-to-noise of 65 dB. Two samples, a paper index card and a corduroy cloth sample were tested. The index card reflects ca. 1% of the incident terahertz energy with similar angular spreading while the corduroy sample reflected approximately 0.01% of the incident terahertz energy with FWHM of 5-10°. The corduroy sample also exhibits temporal pulse scattering as a function of angle which correlates with direct frequency domain measurements.
Proceedings Title
Paper 8022-14, Session: "Passive Milllimeter Wave Imaging Technology XIV"
Volume
8022
Conference Dates
April 24-29, 2011
Conference Location
Orlando, FL, US
Conference Title
SPIE Defense, Security & Sensing
Pub Type
Conferences

Keywords

BRDF, concealed threat detection, terahertz reflection and scattering, terahertz imaging
Optical / photometry / laser metrology

Citation

Lo, S. , Novotny, D. , Grossman, E. and Heilweil, E. (2011), Pulsed terahertz bi-directional reflection distribution function (BRDF) measurements of materials and obscurants, Paper 8022-14, Session: "Passive Milllimeter Wave Imaging Technology XIV", Orlando, FL, US (Accessed October 11, 2025)

Issues

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Created June 12, 2011, Updated October 12, 2021
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