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.

Unlike a sound waves, light waves do not need a medium ... The diagram shows refraction of light passing into, and then out of, a glass block. The same would happen for a Perspex block or for ...

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

In a gradient, light bends towards the higher-index part, as the law of refraction predicts, or according to Fermat's principle. In a homogeneous medium (top and bottom), light does not bend. Mix up ...