Conventional curved lenses, which direct light by refraction in glass or plastic, are often bulky and heavy, offering only ...

In a ray diagram, a concave lens is drawn as a vertical line with inward facing arrows to indicate the shape of the lens.

A plano-concave lens is a lens with one side being flat and the other side being concave. It is characterized by being thin in the center and thick at the edges, and can make parallel light rays ...

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 ...

Enter Rajesh Menon and his team at the U. Their new flat lens offers the same light-bending power as traditional curved ...