Scientists have made a start toward the development of a real 'cloak of invisibility.' Researchers from the United States and England have conducted the first successful experiment with a device designed to prevent microwaves from detecting objects. This device has the ability to hide itself. The system involves a set of concentric copper circles on fiberglass board. It deflects electromagnetic waves of a specific frequency that strike it with only a little of the scattering and absorption that create reflections and shadows. Microwaves generally bounce off objects, which makes them visible to instruments and creates a detectable shadow. In the successful experiment, microwaves slide around the device like water that flows over a smooth rock in a stream, according to David R. Smith, professor of electrical and computer engineering at Duke University. The result is similar to a mirage in which heat causes light rays to bend, cloaking the road ahead with an image of the sky. David Schurig, research associate at Duke's electrical and computer engineering department and the cloak designer, says the scientists have built an artificial mirage that can hide something from viewers in any direction. The device made by the Duke researchers is different from stealth technology, which does not make aircraft invisible, but reduces the area available to radar, which makes the craft difficult to track.