Absorption, transmission, and scattering of expanded polystyrene at millimeter-wave and terahertz frequencies

Charles R. Dietlein; Jon E. Bjarnason; Erich N. Grossman; Zoya Popović

doi:10.1117/12.784598

18 April 2008 Absorption, transmission, and scattering of expanded polystyrene at millimeter-wave and terahertz frequencies

Charles R. Dietlein, Jon E. Bjarnason, Erich N. Grossman, Zoya Popović

Author Affiliations +

Proceedings Volume 6948, Passive Millimeter-Wave Imaging Technology XI; 69480E (2008) https://doi.org/10.1117/12.784598
Event: SPIE Defense and Security Symposium, 2008, Orlando, Florida, United States

Abstract

Conventional material measurements of transmission and reflection in the millimeter-wave and terahertz frequency range do not differentiate between scattering and absorption, grouping effects from both mechanisms together into "loss". Accurate knowledge of the balance between scattering and absorption is critical in applications such as radiometric scene modeling for concealed object detection, where evaluation of object detectability depends strongly on the amount of scattering due to concealers such as clothing. We describe an experimental setup for the measurement of spatial bidirectional reflectance distribution function (BRDF). Previous measurements have shown extremely low-level grating lobes from periodic clothing materials such as corduroy, around 30 dB below the transmitted beam. To adequately address this issue of high dynamic range, we utilize a cryogenic antenna-coupled microbolometer for detection. We present data on several types of expanded polystyrene, a common structural material for systems and experiments in this frequency range. In these measurements of BRDF, transmission agrees with previous measurements, and the balance between low and high angle scattering, specular reflectance, and absorption is examined.

Citation Download Citation

Charles R. Dietlein, Jon E. Bjarnason, Erich N. Grossman, and Zoya Popović "Absorption, transmission, and scattering of expanded polystyrene at millimeter-wave and terahertz frequencies", Proc. SPIE 6948, Passive Millimeter-Wave Imaging Technology XI, 69480E (18 April 2008); https://doi.org/10.1117/12.784598

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available