The research effort centres on so-called metamaterials -- these are artificially engineered structures that have properties not known iin nature, such as the ability to reverse light.

"We are not actually cloaking anything," said Jason Valentine, one of the researchers working on the project.

"I don't think we have to worry about invisible people walking around any time soon."

"To be honest, we are just at the beginning of doing anything like that."

Two different type of metamaterial are being investigated -- one is a fishnet of metal layers, while another uses tiny silver wires, both at the nanoscale level.

Using these metamaterials, researchers have created a scenario where a physical substance has a 'negative refractive index' -- changing the way that it is percieved.

"In naturally occurring material, the index of refraction, a measure of how light bends in a medium, is positive," said Valentine.

"When you see a fish in the water, the fish will appear to be in front of the position it really is."

"Or if you put a stick in the water, the stick seems to bend away from you."

But Valentine pointed out that negative refraction leads to some unusual effects.

"Instead of the fish appearing to be slightly ahead of where it is in the water, it would actually appear to be above the water's surface," he said.

"It's kind of weird."

For now, the technology could be used to improve optical devices -- leading to better microscopes that can observe a living virus in situ.

"However, cloaking may be something that this material could be used for in the future," Valentine said.

"You'd have to wrap whatever you wanted to cloak in the material."

"IIt would just send light around."

"By sending light around the object that is to be cloaked, you don't see it."