Semi-OT Laser pinpoints tiniest traces of explosive

Not only does the laser detect explosive material, but it also provides an image of the chemical’s exact location, even if it’s merely a tiny trace on a zipper. (Credit: Michigan State University)
http://www.futurity.org/laser-pinpoints-tiniest-trace-explosive/?utm_source=Futurity+Today&utm_campaign=38d5bf5a48-September_10_20139_10_2013&utm_medium=email&utm_term=0_e34e8ee443-38d5bf5a48-206318349

 

Michigan State University

My Note: Thanks to Jmat on InvestorVillage for posting a link to this article.

Michigan State University ➡Original Study

Posted by Layne Cameron-Michigan State on September 9, 2013

Laser pinpoints tiniest traces of explosive

A bomb-detecting laser that can find micro-traces of explosive chemicals on clothes and luggage could improve security at airport checkpoints, researchers say.
“Since this method uses a single beam and requires no bulky spectrometers, it is quite practical and could scan many people and their belongings quickly,” says Marcos Dantus, chemistry professor at Michigan State University.
“Not only does it detect the explosive material, but it also provides an image of the chemical’s exact location, even if it’s merely a minute trace on a zipper.”

Marcos Dantus (front) says his bomb-detecting laser could be used at security checkpoints. (Credit: Michigan State University)

This doesn’t mean that security will be armed with handheld lasers in airports. The laser would more likely be in a conveyor belt, like the X-ray scanners already used for airport security. The low-energy laser is safe to use on luggage as well as passengers, Dantus says.
For decades, scientists have been working to develop lasers that are powerful enough for detection, but safe enough to use on people.
Dantus’ initial spark came from a collaboration with Harvard University that developed a laser that could be used to detect cancer, but has the beam output of a simple presentation pointer.

While working on biomedical imaging, I began exploring additional applications,” Dantus says. “We soon learned how effective it was for detecting traces of hazardous substances from distances up to 10 meters away.”

One beam, two pulses

As described in the journal Applied Physics Letters, the bomb-detecting laser works as a single beam, but uses two pulses. The first resonates with certain chemical frequencies found in explosives. The second, a shadow pulse, serves as a reference. A discrepancy between the two pulses indicates the presence of explosive materials.
“The laser is not affected by the color or surface of clothes or luggage,” Dantus says. “The resonant pulse and the shadow pulse are always in balance unless something is detected.
“Our method has Raman chemical specificity, excellent sensitivity, and robust performance on virtually all surfaces.”
An aerospace company has already expressed interest in furthering thes technology. With additional funding, a standalone prototype could be created in about one year, he says.
Funding for the research was provided by the Department of Homeland Security, Science and Technology Directorate. BioPhotonic Solutions is a high-tech company Dantus launched in 2003 to commercialize technology invented by his research group