Paper
3 November 2016 Active terahertz wave imaging system for detecting hidden objects
Author Affiliations +
Abstract
Terahertz wave can penetrate the common dielectric materials such as clothing, cardboard boxes, plastics and so on. Besides, the low photon energy and non-ionizing characteristic of the terahertz wave are especially suitable for the safety inspection of the human body. Terahertz imaging technology has a tremendous potential in the field of security inspection such as stations, airports and other public places. Terahertz wave imaging systems are divided into two categories: active terahertz imaging systems and passive terahertz imaging systems. So far, most terahertz imaging systems work at point to point mechanical scan pattern with the method of passive imaging. The imaging results of passive imaging tend to have low contrast and the image is not clear enough. This paper designs and implements an active terahertz wave imaging system combining terahertz wave transmitting and receiving with a Cassegrain antenna. The terahertz wave at the frequency of 94GHz is created by impact ionization avalanche transit time (IMPATT) diode, focused on the feed element for Cassegrain antenna by high density polyethylene (HDPE) lens, and transmitted to the human body by Cassegrain antenna. The reflected terahertz wave goes the same way it was emitted back to the feed element for Cassegrain antenna, focused on the horn antenna of detector by another high density polyethylene lens. The scanning method is the use of two-dimensional planar mirror, one responsible for horizontal scanning, and another responsible for vertical scanning. Our system can achieve a clear human body image, has better sensitivity and resolution than passive imaging system, and costs much lower than other active imaging system in the meantime.
© (2016) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Yuner Gan, Ming Liu, and Yuejin Zhao "Active terahertz wave imaging system for detecting hidden objects", Proc. SPIE 10030, Infrared, Millimeter-Wave, and Terahertz Technologies IV, 100301M (3 November 2016); https://doi.org/10.1117/12.2245523
Advertisement
Advertisement
RIGHTS & PERMISSIONS
Get copyright permission  Get copyright permission on Copyright Marketplace
KEYWORDS
Terahertz radiation

Imaging systems

Antennas

Millimeter wave imaging

Mirrors

Absorption

Reflectivity

RELATED CONTENT

THz time-domain spectroscopy imaging for mail inspection
Proceedings of SPIE (August 11 2011)
Terahertz imaging for styrofoam inspection
Proceedings of SPIE (September 26 2007)
Terahertz imaging of burned tissue
Proceedings of SPIE (February 01 2007)

Back to Top