Watching the detectors

29 January 2007

Gary Marshall asks on his blog: X-ray cameras on lampposts, is this a wind-up or what? Sadly, I reckon it isn't. Today's story in the Currant Bun describes a Home Office plan - well a memo in which some civil servants think aloud what might be possible having watched Total Recall in a quest for ideas - to put 'X-ray cameras' on various bits of street furniture.

The reasoning is simple. If you can see through people's clothing you can see the weapons they might be carrying. Luckily, the UK government does not want to join other shadier groups in wanting to irradiate us with high-energy photons. The Home Office proposal looks like it is actually referring to terahertz waves rather than X-rays. Being a bit less energetic than infrared light, terahertz waves would merely give our bodies a gentle tickle rather than a good bludgeoning in the way that X-rays would. My guess is that The Sun's editors realised that X-rays would get the point across more quickly and simply than trying to explain terahertz waves.

The giveaway on terahertz is the idea that the images would look through clothing and reveal people - as opposed to people's bones. The technology has been tried in airports and, with some techniques in research at the moment, it will be possible to shrink the electronics needed down to about the size of a shoebox in a few years. So, that bit is almost certainly not a wind-up. Whether the policy behind it is a wind-up is another matter.