Definition of OPTICS

Optics is branch of physics in which we study the nature and propagation of light. Newton, the greatest among the great, believed that light is a collection of particles. He believed that a light source emits tiny corpuscles of light and these corpuscles travel in straight lines when not acted upon by external forces. The fact that light seems to travel in straight lines and cast shadows behind the obstacles were perhaps the strongest evidence of the particle nature of light. Newton could explain the laws of reflection of light on the basis of elastic collision of the particles of light with the surface it is incident upon. The laws of refraction were explained by assuming that the particles of denser medium, such as glass or water, strongly attract the particles of light causing a bending at the surface. Newton assembled these experiments in the form of a book optics.