Conventional curved lenses, which direct light by refraction in glass or plastic, are often bulky and heavy, offering only limited control of light waves. Metasurfaces, in contrast, are flat and ...

A ray diagram showing refraction at the boundary between air and glass Refraction can cause optical illusions as the light waves appear to come from a different position to their actual source.

Science presenter Jon Chase explains the refraction of light. He demonstrates how refraction can make the handle of a Pyrex jug seemingly disappear. He explains this is because when light travels ...