Since 9-11 TSA and DHS have been besieged with detector proposals for ferreting out passengers attempting to conceal explosives and hazardous substances beneath their clothing. They have run the gamut of technical ambition, most bad, many ugly, and variously plagued by poor signal-to-noise ratios and alarming false positive rates. Some that work do so more by brute force than technical elegance- what can't you detect with a MR scanner, a sawed off synchotron .and a megabuck array of single crystal gadolinium scintillators ?
This sub-terahertz gadget relies on the short end of the ambient millimeter wave spectrum to illuminate the difference between what people are made of and what they may be carrying. Advances in high electron mobility indium phosphide semiconductor detectors and a MIMIC amplifier allow a simple dielectric lens (the white-domed top of the hooded cocktail shaker in the photo) to give passengers the once over at a few hundred gigahertz, to see if they are plain vanilla humans, or packing liquid or solid contraband that does not match the dielectric properties of flesh, blood, and bone.
The dielectric lens and a boresighted video camera ( the cocktail shaker's dark spout ) afford a magnified directional view fed to an internal millimeter wavelength horn antenna and a one dimensional scan train not much more complicated than a bar code reader. Discrimination is afforded by proprietary AI firmware that presumably has total recall of what people look like over several wavelengths, allowing comparison of the real-time background illumination with what emanates from a target up to several hundred feet away.
If a passenger's millimeter wave profile lights up as anomalous, security people come into play to see what he or she may be hiding. This is a very simple system , but MIMIC devices lend themselves to phased arrays, and the technology could grow into a sophisticated imaging system if this early embodiment delivers high passenger throughput and few false positives. A larger roadside version can detect concealed passengers in soft-sided Brit lorries, but here in the land of metal truck bodies , it will probably be debuting in airports rather than Ro-Ro terminals.