Researchers have created a surface that can act as an antenna.
The researchers made this accomplishment by "depositing an array of tiny, metallic, U-shaped structures onto a dielectric material," an American Institute of Physics (AIP) news release reported.
The surface has the ability to "bend and focus electromagnetic waves" in a similar fashion to an antenna. The invention has been dubbed the "broadband transformation optics metasurface lens," the news release reported.
The surface could lead antennae that are "low profile" and can conform to a number of different surfaces.
The surface has completely artificial properties that could never be found in nature; the U-shaped elements cause it to mimic a Luneburg lens.
Luneburg lenses are usually spherical optics that have a unique way of interacting with light. Some lenses have a higher "index of refraction" than others, meaning that they bend light more than lenses made from other substances.
A Luneburg lens bends light based on where the light hits it; this phenomenon occurs because the lens' index of refraction varies across its surface.
The unusual properties of Luneburg lenses allow them to "focus light or incoming electromagnetic waves to an off-axis point at the edge of the lens (not directly in front or behind it as a normal lens would do)," the news release reported. The lenses also have the ability to "uniformly channel electromagnetic waves" that come from a nearby source and send them in a specific direction.
The researchers have now created a flat Luneburg lens, which will be more versatile than the common spherical shape.
"We now have three systematical designing methods to manipulate the surface waves with inhomogeneous metasurfaces, the geometric optics, holographic optics, and transformation optics," Tie Jun Cui of Southeast University in Nanjing, China said in the news release. "These technologies can be combined to exploit more complicated applications."
