IN the wave theory of light, the geometrical laws of optics—rectilinear propagation, reflection and refraction—and other results besides, rest on a single principle. The fundamental postulate is that ...

Light bends when travelling through a concentration gradient of sugar in water. The top layer of liquid is pure water while the bottom layer is concentrated sugar water. In these layers, there is no ...

Optical imaging systems have been playing an essential role in scientific discovery and societal progress for several centuries. For more than 150 years scientists and engineers have used aberration ...