In a paper submitted to the American Journal of Physics, University of Rochester physicist John Howell and his 14-year-old son, J. Benjamin Howell, say such cloaking devices can conceal high-flying satellites.
You can watch an example in this video in which one boy´s body appears to be missing below the head, even when another boy walks around behind him. The trick is that two sets of mirrors have been placed in such a way as to reflect the scene behind the "cloaking region" in which the seemingly disembodied kid is standing. (The actors in the movie are all John Howell´s sons — Paul and James above, Benjamin and Isaac below.)
The cloaking effect isn´t perfect. A wider-angle view would show you the retro-reflecting mirror, standing off to the side. Another major drawback is the fact that the effect is uni-directional: If you move around to a different position, the effect is spoiled.
The device could have important implications for sending secret messages via fibre optic cables.
It can hide a continuous stream of events at telecommunications data rates – much quicker than a similar invention unveiled last year. Researchers used equipment known as modulators to make the holes by bending light, Nature reported.
Although a long way off the fictional ´invisibility cloaks´ featured in Star Trek and the Harry Potter films the concept could have practical applications to conceal messages.