Learn Polarisation Of Light Class 12

Basic Requirements

• Class 12 Student

Skills Covered

• Plane Of Vibration

• Polarisation By Scattering

Expert Review

Polarization is defined as:

Physics defines the phenomenon of Polarization as arising from the wave-like nature of electromagnetic radiation. Light travels through the vacuum to reach the Earth, which is an example of an electromagnetic wave. They are called electromagnetic waves because they are produced by the interaction of an electric field with a magnetic field. You will learn about two types of waves in this article, transverse waves, and longitudinal waves. Additionally, you will learn about polarization and plane-polarized light.

Transverse waves

A transverse wave is a wave in which particles move perpendicularly to its direction of motion.

Example 1:

The ripples were caused by a stone thrown into the water.

Example 2: 

A sound wave moving through the air.

A longitudinal wave occurs when the particles of the medium move in the same direction as the waves.

Light is the interaction of electric and magnetic fields in space. Light waves have electric and magnetic vibrations that are perpendicular to one another. Electric and magnetic fields move in opposing directions, but always perpendicularly. The electric field occupies one plane, the magnetic field lies perpendicular to it, and the direction of travel is perpendicular to both. Magnetic and electric vibrations can occur on many planes at the same time. Light waves that vibrate in more than one plane are known as unpolarized light waves. Sunlight, lamplight, and tube lights all emit unpolarised light. As shown in the image below, the direction of propagation remains constant, but the planes on which the amplitude occurs change.

Types of Polarization

Based on the transverse and longitudinal motion of waves, there are three types of polarization:

1) Linear polarization

2) Circular polarization

3) Elliptical polarization

4) Linear Polarization

Light propagates in a single plane with linear polarization.

Elliptical Polarization

Light propagates along an elliptical path. In the two linear components, there is a difference in amplitude and phase.

Methods Used in the Polarization of Light

In polarizing light, some methods are utilized:

1) Polarization through transmission

2) Polarization by Reflection

3) Polarization by Scattering

4) Polarization by Refraction

Applications of Polarization

Polarization can be applied in the following ways:

1) Sunglasses use polarization to reduce glare.

2) Plastic industries use Polaroid filters to perform stress analysis tests.

3) Polarization is used to produce and display three-dimensional movies.

4) Transverse and longitudinal waves are distinguished using polarization.

5) Polarization is used in infrared spectroscopy.

6) Seismologists use it to study earthquakes.

7) Using polarization techniques, organic compounds can be tested for their chirality in Chemistry.