Cloaking

Scientists create cloak of invisibility

By RANDOLPH E. SCHMID, AP Science Writer Thu Oct 19, 9:49 AM ET

WASHINGTON - A team of American and British researchers has made a Cloak of Invisibility. Well, OK, it's not perfect. Yet. But it's a start, and it did a pretty good job of hiding a copper cylinder.

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"The cloak reduces both an object's reflection and its shadow, either of which would enable its detection," said Smith.

In effect the device, made of metamaterials — engineered mixtures of metal and circuit board materials, which could include ceramic, Teflon or fiber composite materials — channels the microwaves around the object being hidden.

When water flows around a rock, Smith explained, the water recombines after it passes the rock and people looking at the water downstream would never know it had passed a rock.

The cloaking has to be designed for specific bandwidths of radiation.