Coatings that conceal real objects

Researchers at the Pennsylvania State University in the US have developed "illusion coatings" that can hide things by making them appear like something else.

The so-called "illusion coatings" - flexible, light-weight materials - could help soldiers or spies hide antennae and sensors from view while still allowing the devices to scan the outside world.

"The demonstrated illusion/cloaking coating is a light-weight two-dimensional metasurface, not a bulky three-dimensional metamaterial," said Douglas Werner from the Pennsylvania State University.

The new coating of a negligible thickness allows coated objects to function normally while appearing as something different or even completely disappearing, Live Science reported.

The coating is made of thin sheets of a composite material composed of glass fibres and Teflon. These were covered with patterns of copper stripes that interacted with the composite material to scatter radio waves in a very precise way. The stripes are one third the thickness of a human hair.

Depending on the copper patterns used, the coating can make a copper antenna or sensor appear to be silicon or Teflon.

The researchers published their findings in the journal Advanced Functional Materials.