Tuneable Windows Keep Office Secrets

"Walls have ears" is the old saying that advises against discussing secrets in apparently empty rooms. These days it's the windows that pose more of a threat to our secrecy. While there are many means of protecting sealed rooms from radio and microwave snooping, if the room has a window that protection has a weakness.

Not any more though - now that researchers at the UK's University of Warwick have devised a method of producing tuneable surfaces that can selectively block signals from wireless networks. Dr Christos Mias from the university's School of Engineering has developed a "dipole grid based frequency-selective surface" (also known as an FSS surface) to perform this task.

This grid of circuitry has the potential to be embedded in any glass window and then tuned to block the selected frequency. Given the value we all place on our privacy Dr. Mias work may yet prove - to coin another old saying - that "silence is golden"!!