Anti-Radio Signal paint offers security

RF Paint

“Researchers say they have created a special kind of paint which can block out wireless signals”

Researchers at the University of Tokyo in Japan have created a special paint which can block out wireless signals. The paint, which could cost as little at £10 per kilogram, contains an aluminium-iron oxide which resonates at the same frequency as wi-fi – or other radio waves – meaning the airborne data is absorbed and blocked. While paints blocking lower frequencies have been available for some time, this new technology is the first to absorb frequencies transmitting as high as 100GHz (gigahertz). Signals carrying a larger amount of data – such as wireless internet – travel at a higher frequency than, for example, FM radio.

The paint has a number of interesting potential applications including: keeping wireless networks secure, blocking phone calls during movies, shielding hospital rooms from unwanted electromagnetic radiation, and making clothes that protect people from electromagnetic waves.

The paint contains an aluminium-iron oxide which resonates at the same frequency as wi-fi – or other radio waves – meaning the airborne data is absorbed and blocked.

By coating an entire room, signals can’t get in and, crucially, can’t get out.

Developed at the University of Tokyo, the paint could cost as little as £10 per kilogram, researchers say.

Cost-effective security

The makers say that for businesses it’s a quick and cheap way of preventing access to sensitive data from unauthorised users. Presently, most companies have to invest in complicated encryption software to deter hackers.

Speaking on the BBC World Service’s Digital Planet programme, Shin-ichi Ohkoshi, who is leading the project, explained how the paint could have many uses beyond security.

“In a medical setting, you could transmit large volumes of data from a medical device, such as an endoscope, to a computer.

While paints blocking lower frequencies have been available for some time, Mr Ohkoshi’s technology is the first to absorb frequencies transmitting at 100GHz (gigahertz). Signals carrying a larger amount of data – such as wireless internet – travel at a higher frequency than, for example, FM radio.

“Our current mobile phones work at much lower frequencies, around 1.5 gigahertz. But, our material can also absorb frequencies that low, so you could block phone signals from outside and stop people’s phones ringing during the movie,” he said.

As well as helping to keep the cinema quiet, the paint may also pave the way for higher quality screens.

“Movie pictures are beamed on the screen by the projector at the back of the cinema. But in the future, you could use a data link that works with millimetre waves.

Will it work as low observable technology for Aircraft?