"A functional superlens would be a major breakthrough in optics and was first envisioned five years ago. The idea is to use exotic types of materials, proposed in the late 1960s, to create ‘negative’ refraction of light, which literally means steering it in the opposite direction of that found in the natural world. The first materials that could do this were created a few years ago and the field is one of significant scientific interest, but many obstacles remain…"