Laser listening devices designed to pick up vibrations produced by sound waves bouncing off solid surfaces could be used by spies looking to learn about surveillance leaks, the U.K. government warned The Guardian newspaper.
The devices, which look similar to cameras and can be operated by a single person, have been around for five to 10 years, says Jeremy Marks, director of spy equipment retailer Spycatcher Online. For the laser to work, the operator needs a direct line to a target not much more than 1,600 feet away. Conversations can be reconstructed when the laser returns to the receiver and the vibrations are decoded.
A spokesman for Ukraine-based manufacturing firm Argo-A Security said its version of the equipment costs $17,000 to $40,000 and that it sells its devices only to law enforcement and government agencies. (That limitation is possible, but it is difficult to believe an average capitalist would turn down an opportunity to make a profit.)
Marks told the BBC that laser eavesdropping devices are not where spies are likely to begin. “It wouldn’t be my first choice for sure,” he said. “If you’ve exhausted other methods, then yes, you would.” Security experts say other eavesdropping devices placed in target rooms, such as mobile phones or “modulating light”—where LED bulbs pick up and transmit light signals—are more effective.
—Posted by Alexander Reed Kelly.
While there are measures to combat this sort of eavesdropping, it is very hard to ensure your conversations will not be heard, one counter-surveillance specialist said.
“It is extremely difficult to protect any room with a window,” said James Williams, the operations director of QCC Interscan, which provides counter-eavesdropping protection services to the government and private clients.
… The installation of counter-intelligence window film is one effective protection measure, he added. Adding heavy curtains to windows could also absorb some of the sound vibrations in a room.
Conversations can be reconstructed from the data in the laser signal
But he added that lasers are trained to pick up certain frequencies and could still be recalibrated to get around those hurdles.
tjmwatson (CC BY 2.0)