When a wave or light ray moves from one medium to another its speed changes. The direction of the ray may also change. This property of waves is called refraction and commonly occurs with light rays.

Soft X‐ray diffraction gratings coupled with advanced multilayer coatings represent a pivotal innovation in the development of high‐resolution spectroscopic instruments. These devices utilise periodic ...

This video looks at the refraction of light and demonstrates how refraction can make the handle of a Pyrex jug seemingly disappear.