What is a ‘naked camera’ anyway?

An Ask the Expert feature with Acquris

Johan Öhgren of Acquris investigates airport security.

“The system will automatically detect a suspicious object and present the outline on top of a normal video image on the monitor”
-Johan Öhgren, Acquris

All who pass an airports security checkpoint today are forced to remove jackets, coats, computers from their cases and sometimes belts, shoes, etc. In general, it’s painstakingly slow and is privacy intrusive; but it’s for the greater good and helps us keep safe.

However, one of the problems with the traditional techniques like the x-ray machine and the metal detector arches in security check point, is that it’s virtually impossible to detect non-metallic items like sharp plastic and ceramic items that could also be used as weapons. The current way to combat this is to set the detector to go off after a slightly randomised number of people passing the arch, regardless if they carry any metal items or not.

The object is to keep officers on their toes and pat people down. The aim is to discourage terrorists or criminals to try to sneak something through. In a perfect world, this makes it impossible to carry on any hazardous items onboard aircrafts. Unfortunately, as we all know, we do not live in a perfect world.

Contrary to popular belief, it’s quite easy to get through with weapons, explosives, Tazers and other dangerous items. To keep up some kind of pace in the security checks, the officers never or at least rarely stop anyone passing the metal detector if it hasn’t given off an alarm. This is the Achilles heel; we don’t get checked what we hide under our clothes unless the alarm sounds. As matter of fact, even when the detector gives of an alarm, the officer sometimes misses obvious items due to intimidation factor, charm or plain laziness.

These facts allowed for undercover agents working for the Transportation Security Administration to cross the checkpoint at several US airports with guns, knives and improved explosive devices. In fact, when tests were carried out at Denver International Airport in 2007, in 10% of the cases the items were detected but in the remaining 90% passed the checkpoints without being found.

In 2006, Department of Homeland Security's Office of Inspector General and the US Government Accountability Office (GAO) found widespread failures in US airports. According to the GAO, at 15 tested airports, security screeners only found 10% of the guns and explosives the undercover agent tried to sneak past.

This is why there is extensive research throughout Europe and US in new technologies to aid the security screeners in combating terrorists, insurgence and criminals. One of the more promising technologies has been nicknamed ‘naked camera’ due to its ability to see through clothes and being based on ultra-high radio waves named THz.

This is the reason behind the IMATERA project – IMAging in the TERAherz domain. This EU research project, under the PEDEA+ umbrella is part of EUREKA within the EU, aims to address this problem.

The difference in the IMATERA projects, compared to other ‘naked cameras’, is that we work in higher frequency, in real time and in room temperature. All of this together gives a higher resolution image of what is hidden underneath the clothes a person is wearing, down to a size of some mm.

With all this power, the IMATERA projects have also addressed the invasion of privacy issues, which many other projects forget. Instead the system will automatically detect a suspicions object and present the outline on top of a normal video image on the monitor. This way, the machine could also be used in orthodox Muslim countries since the device won’t cause any religious or integrity problems. With this approach, the machine, can not only work in assisting screeners, but it also allows for automated security checkpoints at lower security areas like a sports arena.

The research part in the IMATERA project stretches until 2011 and a device based on this technology will probably be available on the market around 2012-2015.

Johan Öhgren is the owner of Acquris IT HB. Acquris is one of a few companies that handle the complete chain, from developing to fabrication to installation of both overt and covert camera surveillance system. Öhgren is the Swedish National Co-ordinator in the IMATERA project.