Genia Photonics has developed a programmable picosecond laser that is capable of spotting trace amounts of a variety of substances, including explosives, chemical agents, and hazardous biological substances at up to 50 meters.

It’s basically a spectrometer for radiation in the terahertz band. The beam used by Genia’s spectrometer is capable of penetrating most materials including wood, leather, cloth, ceramics, plastic, and paper, and can essentially scan the surface of your body through clothing looking for traces of dangerous substances.

The terahertz signals used are non-ionizing and very low power, so at least it’s safe. But that gunpowder residue on your hand from hunting the other day, cannabis smoke particles in your hair, or even a bit of (explosive-boosting) nitrate fertilizer stuck to your shoe could trigger this scanner. Will that cause an entirely new set of headaches for airline passengers?

Genia also cites medical applications.