[amalia (OP)]

Paul wrote to us with a cool idea:
Can a remote scanner be developed which would enable police to scan folk from a distance and determine if they were armed with a knife? If so this device could also work in tandem with CCTV so the police can see them on CCTV and also determine that they were carrying knives.
What do you think?

[alancalverd]

I work for a company that makes x-ray portal scanners. We have demonstrated that 50% of US long-term high security prisoners have  a knife, mobile phone, or both, but some prissy idiots have determined that these simple and effective scanners shall not be used in UK airports because the operator might be able to see your genitals through your underwear. (Believe me, it loses any possible fascination early in the first 8 hour shift, and the initial scan is machine-read anyway). So instead, they use crude metal detectors and waste hours groping passengers and hand-scanning hip implants and zip fasteners.

Problem with a remote knife detector is to get sufficient resolution at a distance to tell the difference between a knife and anything else. 

[evan_au]

I have been scanned several times using TeraHertz waves.
But you have to stand on the footprints conveniently painted on the floor, and hold your hands up so they can check you aren't hiding something under your armpits....

[Belseltad]

The feeling of me now is very glad to be with everyone here.

[Gutalin]

But you have to stand on the footprints conveniently painted on the floor.