SCIENTISTS in the United States have reported a further step towards a celebrated ''invisibility cloak'' by masking a large, free-standing object in three dimensions.

The lab work is the latest advance in a scientific frontier that uses novel materials to manipulate light, a trick that is of huge interest to the military in particular.

A war plane cloaked with such materials could achieve 'super stealth' status by becoming invisible in all directions to radar waves. Credit:Reuters

Reporting in the New Journal of Physics, researchers at the University of Texas at Austin cloaked an 18-centimetre tube from light in the microwave part of the energy spectrum.

Those hoping for a Harry Potter-style touch of wizardry would be disappointed. To the human eye, the object was still visible.