U.S. researchers say they have "cloaked" a three-dimensional object, making it invisible from all angles for the first time.

The process uses a shell of what are known as plasmonic materials that create a "photo negative" of the object being cloaked, effectively canceling it out.

However, the demonstration has only been achieved for waves in the microwave region of the electromagnetic spectrum, not for visible light.

Andrea Alu and colleagues at the University of Texas at Austin have made a 7-inch-long cylinder invisible to incoming microwave light.

The success with the cylinder suggests further work with different wavelengths of light is worth pursuing, Alu said.

"It's a real object standing in our lab, and it basically disappears," he told BBC News.

While the technique is unlikely to work at the visible light part of the spectrum, Alu said, the approach could be applied to the tips of scanning microscopes to yield an improved view of even smaller wavelengths of light.