Landmine scanner can detect TNT 'signature'

Scientists have developed a prototype device for detecting plastic landmines by picking up the unique atomic signature of the chemical explosive.

Scientists have developed a prototype device for detecting plastic landmines by picking up the unique atomic signature of the chemical explosive.

The detector could help to prevent thousands of deaths and mutilations that occur each year among civilians living in former war zones.

Conventional metal-detectors are next to useless against plastic mines, which contain less than a gram of metal, as even a small nail or tiny piece of shrapnel on a former battlefield can lead to a time-consuming false alarm.

Researchers at America's Naval Research Laboratory in Washington DC have instead concentrated on a technique called nuclear quadrupole resonance, which was originally developed for airport explosives scanners. It uses energetic pulses of radio waves which cause chemical explosives, such as TNT, to emit a characteristic "echo" which can be detected by a sensitive radio receiver.