Charles Harb doesn’t want to put bomb sniffer dogs out of a job, but a laser device developed at UNSW Canberra capable of detecting tiny traces of explosive vapour might just do that.

The machine is “about 100 times more sensitive and … 100 times faster than any other detection device”, according to Associate Professor Harb, from the School of Electrical Engineering and Information Technology. 

A prototype of the device – a pulsed, quantum laser-based, cavity ringdown spectrometer – is now being tested at the US Government’s Los Alamos National Laboratory in New Mexico.

The device could be positioned to “sniff” bags travelling along a conveyor belt and instantly alert security personnel if it detects explosive vapours coming from a passing suitcase.

Ultimately it could replace sniffer dogs and those intrusive and unpopular airport security checks such as full body scans and pat downs as well as the inconvenience of having to remove shoes, jackets and belts.

Other devices exist that can detect vapour from explosives, but they are nowhere near as fast, Associate Professor Harb says. The reason is as simple as an old magic trick – it’s done with mirrors.

“Using mirrors we got the laser to repeatedly pass through the vapour in a figure-of-eight path. That gave us a much more accurate measurement,” he says

“We can measure the components of TNT very clearly – down to the tiny sub-millitorr pressures, in other words in the parts per billion range in atmosphere.”

Read the full story in the latest issue of Uniken.

Media contactSteve OffnerUniken Editor, 02 9385 1583