Distinguish, differentiate, compare and explain what is the difference between Fresnel and Fraunhofer diffraction.
The spreading out of light wave into the geometrical shadow when it passes through a narrow opening is known as the diffraction. The difference between Fresnel and Fraunhofer diffraction are as follows-
Comparison and difference between Fresnel and Fraunhofer Diffraction
- In fresnel diffraction, the source and the screen are at a finite distance from the diffracting aperture whereas, in Fraunhofer diffraction, the source, and the screen are at an infinite distance from the diffracting aperture.
- For obtaining Fresnel diffraction, zone plates are used. In Fraunhofer diffraction, the single-double plane diffraction grating is used.
- In Fresnel, the wave-fronts are divergent either spherical and cylindrical while in Fraunhofer, the wave-fronts are the plane which is realized by using the convex lens.
- In Fresnel, no mirror or lenses are used for observations while in Fraunhofer, diffracted light is collected by a lens as in a telescope.