scientists to create invisible clock

British and German researchers have created the three-dimensional that can hide objects by bending light waves, which could pave the way for larger objects to be made invisible.

While the cloak of invisibility has played a major role in fiction and movies, it appears that scientists have taken a small, but important new step, toward making it reality.
In their study, researchers from the German Karlsruhe Institute of Technology and Imperial College London used the cloak, made using photonic crystals with a structure resembling piles of wood, to conceal a small bump on a gold surface.

In their study, published Thursday in the American journal Science, they rendered almost entirely invisible the bump that measured 0.00004 inches high by 0.00005 inches across, by "cloaking" it in a new material.

Invisibility cloaks have already been developed but they only worked on two dimensions.

In other words, the objects that were supposed to be made invisible were immediately visible from the third dimension, the study said.

The "cloak" invented by the European team is the first to work on three dimensions.

It is composed of special lenses that bend light waves to suppress light as it scattered from the tiny bump the researchers were trying to make disappear, the study says.

"For now these ... cloaking devices are just a beautiful and exciting benchmark to show what transformation optics can do," said Tolga Ergin, who led the research.

"This is very exciting, because mankind has always thought about being invisible or having invisibility cloaks.

"This is the first proof of principle. It shows that the technique works.

He added: "The value of the finding is that we learn more about the concepts of transformation optics, and that we have made a first step in producing 3-D structures in that field."

He cautioned that it likely be years before anything as large as a person, car or tank could be made to disappear with this technique.

"There have been proposals in the field of transformation optics for different devices like beam concentrators, beam shifters, super antennas which concentrate light into one point from all directions, and much, much more," he said.

"It is really hard to say what the future will bring, but the field is definitely very broad and the possibilities are very large."