REFLECTION

Reflection Of  Light

When  you throw anything against the wall, it bounces back off the wall. Similarly, light travelling in a straight line  bounces back or reflects when it strikes the surface of another  medium.  The amount and direction of the reflected light depends on the surface it strikes.

When a parallel light beam strikes a smooth surface, it will be reflected as a parallel beam. Non-parallel light rays striking a smooth surface will produce either diverging or converging reflected rays which form sharp images. Reflection from a smooth surface is called regular reflection. Mirrors and polished metals have smooth surfaces which produce regular reflections and sharp images.

Parallel rays of light falling onto a rough surface are scattered  in different directions. This type of reflection is called diffused or scattered reflection and no images are formed.