Researchers at MIT have created a 3D metamaterial lens that focuses radio waves with extreme precision. Through “negative refraction”, the concave lens bends electromagnetic waves in exactly the opposite way from how a normal concave lens would work. Instead of spreading the radio waves, they are focused on a single point like a tight beam.
Isaac Ehrenberg, an MIT grad student in mechanical engineering, fabricated his design using 3D printing, by building a lens layer by intricate layer from a polymer solution. After washing away the residue with a high-pressure water jet, each layer was coated with a fine mist of copper to give the lens a conductive surface.
Ehrenberg says the device, which weighs less than a pound, would be easy for others to replicate in order to investigate 3D metamaterial designs. It could be used to focus radio waves precisely on molecules to create high-resolution images and has potential applications in deep-space imaging.