Diffraction of Light
The phenomenon of diffraction was first discovered by Girmaldi. Its experimental study was done by Newton’s and young. The theoretical explanation was first given by Fresnel’s.
1) The phenomenon of bending of light around the corners of an obstacle/ aperture of the size of the wave length of the light is called diffraction.
2) The phenomenon resulting from the superposition of secondary wavelets originating from different parts of the same wave front is defined as diffraction of light.
3) Diffraction is the characteristic of all types of waves.
4) Greater the wave length of wave higher will be its degree of diffraction.
Types of Diffraction:
1) Fresnel Diffraction: If either source of screen or both are at finite distance from the diffracting device, the diffraction is called Fresnel type.
2) Fraunhofer Diffraction: In this case both source and screen are effectively at infinite distance from the diffracting device.