Utah researchers demonstrated the capabilities of their flat lens with test images of the sun and moon. Credit: Menon Lab, University of Utah For centuries, lenses have worked the same way: curved glass or plastic bending light to bring images into focus. But traditional lenses have a major drawback—the more powerful they need to be, the bulkier and heavier they become. Scientists have long searched for a way to reduce the weight of lenses without sacrificing functionality. And while some slimme...