Finding explosives with laser beams

At the Vienna University of Technology, a new method has been developed to detect chemicals inside a closed container over a distance of more than a hundred meters. After the sample is irradiated with a laser beam, the light is scattered by the molecules of the sample, and the energy is changed. This changes the wavelength of the light -- and thus its color; laser light is scattered in a very specific way by different substances and, after analyzing the color spectrum of the scattered light, scientists can determine what kind of molecules are involved. Due to technological advancements, measurements can now be made over long distances. The new method could make security checks at the airport a lot easier -- but the area of application is much wider.