Diffraction and polarization

1. Diffraction and
Polarization

2. Contents
1. Definition of Diffraction
2. Types of Diffraction
3. Definition of Polarization
4. Types of Polarized Light
5. Brewster’s law and Brewster’s Angle

3. Diffraction
Diffraction of light is defined as the bending of light around corners such that it spreads out and illuminates
areas where a shadow is expected.
𝑑𝑠𝑖𝑛θ = 𝑛λ

4. Types of Diffraction
Fresnel Diffraction Fraunhofer Diffraction
Here the wavefront used is spherical. Here the wavefront used is plane.
An image is formed at a finite distance An image is formed at an infinite distance.
A lens is not required. A lens is required.

5. Polarization
Polarization a phenomenon caused due to the wave nature of electromagnetic radiation. Sunlight travels
through the vacuum to reach the Earth, which is an example of an electromagnetic wave. These waves are
called electromagnetic waves because they form when an electric field interacts with a magnetic field.

6. Types of Polarized Light
Linear Polarization: In linear polarization, the electric field of light is limited to a single plane along the
direction of propagation.
Circular Polarization: There are two linear components in the electric field of light that are perpendicular
to each other such that their amplitudes are equal, but the phase difference is π/2. The propagation of
the occurring electric field will be in a circular motion.
Elliptical Polarization: The electric field of light follows an elliptical propagation. The amplitude and phase
difference between the two linear components are not equal.

7. Brewster’s Law & Brewster’s Angle
When an unpolarized light of known wavelength is incident on a transparent substance surface, it
experiences maximum plan polarization at the angle of incidence whose tangent is the refractive index of
the substance for the wavelength.
The polarization angle is also called Brewster’s angle. It is an angle of incidence where the ray of light
having a p-polarization is transmitted through a dielectric surface that is transparent without any
reflection. While the unpolarized light at this angle is transmitted, the light is reflected from the surface.

8. Thank you