Diffraction of light is the phenomenon of bending of light around the corners of the small obstacles and hence its encroachment in the region of geometrical shadows. Diffraction can be classified into two types.
- Fresnel diffraction: Fresnel diffraction is caused by the light from a point source. In Fresnel diffraction, the incident and the diffracted wavelengths are spherical or cylindrical. The source and the screen are at a finite distance from the obstacle causing diffraction. The incident beam from the point source will be a divergent beam, whereas the diffracted beam is a convergent beam.
- Fraunhofer’s diffraction: The incident and the diffracted wavefronts are both planes. The incident and diffracted beams are parallel. The source and the screen are at infinite distance from each other.
