Producing the perfect color images we need and love often requires multiple, heavy lenses so that each color focuses in exactly the same plane. Now Penn State engineers have developed a new theory that solves the problem using a single thin lens comprised of gradient index materials and metasurface layers to properly direct the light. “If we want high performance optical systems, then we have to overcome material dispersion,” said Sawyer D. Campbell, assistant research professor in electrical engineering. “If we don’t, we get smeary colors, which significantly degrades image quality.”