Contrary to what some cartoons might have led you to believe, explosives aren’t always emblazoned with the letters TNT making them easy to identify. Some people will actually go to the trouble of disguising explosives by placing them in nondescript containers. This means that to analyze them, some close quarter examination that puts someone at risk is usually required. Researchers at the Vienna University of Technology (TU Vienna) have developed a detection method using laser light that allows explosives to be detected not only from distances of over 100 meters (328 ft), but works even when the explosives are hidden inside an opaque container.
Read the full article: Using lasers to look through container walls from a distance and detect explosives