Scientists in the United States have moved a step closer to one of the ultimate fantasies of science fiction - a cloak that makes things invisible.

But don't go searching for one yet at your local magic store.

The so called invisibility cloak is still in the preliminary stages. A prototype made by scientists of Duke University in Durham North Carolina has succeeded in hiding objects from microwaves, demonstrating the feasibility of technology that could ultimately shield objects from human sight.

The technology works by using materials that bend electromagnetic waves, including light waves, around objects.

The scientists manufactured the cloak using a set of concentric copper circles printed with intricate patterns that deflect electromagnetic waves of a specific frequency that strike it, without much of the scattering and absorption that make reflections and shadows.

The cloak represents "one of the most elaborate meta material structures yet designed and produced" the scientists said in a paper published yesterday in the journal Science.

It also represents the most comprehensive approach to invisibility yet realised, with the theoretical potential to hide objects of any size or material.

By incorporating complex material properties, our cloak allows a concealed volume, plus the cloak, to appear to have properties similar to free space when viewed externally. Said David Smith, a professor of electrical and computer engineering at Duke.

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

But Smith warned against any imminent expectation for real invisibility. The work is really a scientific explanation, he told The New York Times. Whether it is useful is always a question.

Smith explained that to make objects truly invisible to the human eye, the array of meta materials would need to warp electromagnetic waves at all frequencies. Smith said that the chances of creating such a system were dim but not impossible under the new system.