A newly-developed remote sensing technology has the potential to sniff out hidden explosives, chemicals and illegal drugs and do it from 65 feet away.
The sensors, which use terahertz (THz) wave technology, detect the unique terahertz waves of specific materials, whether they are coming from an individuals pocket, purse or a package.
Traditionally, detection of THz waves was limited to mere inches. THz, which is the portion of the electromagnetic spectrum between infrared and microwave light, are naturally absorbed by ambient moisture in the air, killing the signal.
According to physicist Jingle Liu of Rensselaer Polytechnic Institute, lead author of the recently-published study in Nature Photonics, A lot of other researchers thought that terahertz remote sensing was mission impossible.
Instead, Lius team used reflections created by lasers pointed at a target to detect the waves. The lasers, set at different frequencies, generate ionized air, which emits a reflective florescence, easily detectible from long distances.
Researchers have begun testing hundreds of various substances, creating a library of signals, in order to instantly identify when a specific material is detected.
Homeland security and military agencies have been struggling for years to get technology like this, said terahertz expert Abul Azad at Los Alamos National Laboratory. I think the approach they have revealed is really, really unique.
Terrorist threats have fueled interest in developing THz remote sensing capabilities. Unlike x-rays, THz radiation poses little or no health threat, according to the Rensselaer Polytechnic Institute.
Though the technology, which is portable, makes it a natural for airport security, its first application will be in the military for remote detection of roadside bombs.
