Polarisation of light is one of the key characteristics of light radiations. The polarization of light can be defined as the phenomenon by virtue of which the light radiations tend to vibrate in a single plane. On the other hand, unpolarized waves are light radiations that tend to vibrate in more than one plane. This means that polarized light radiation oscillates in a single direction; whereas, the unpolarized light waves oscillate or vibrate in multiple directions. The polarisation property of light helps in determining the direction of the oscillation of the light waves.
Examples of Polarization of Light
1. Sunglasses
The polarisation of light can be observed easily by looking at the structure of sunglasses or goggles. Here, the polarisation property of light radiations is used to reduce glare and provide comfort to the eyes of the user.
2. Spectroscopy
A number of spectroscopy techniques such as infrared spectroscopy make use of the polarization of light.
3. Three-dimensional Movies
The making of three-dimensional movies or pictures is typically possible due to the polarization property of radiations. A three-dimensional movie typically consists of two separate rolls of film. These two film rolls are used to record the same scenario but from different angles. The projector that is used to display the three-dimensional movie typically consists of two different lenses that are connected to their individual polarizers. Both the polarizers are located at right angles to each other. The lenses of the three-dimensional glasses that are used to see the three-dimensional movies are cross-polarized. This means that the left side of the three-dimensional glass corresponds to the left lens of the camera, while the right side of the three-dimensional glass is analogous to the right lens of the recording camera. This helps display the movie in the exact format as it was recorded.
4. Industries
Various industries such as plastic industries, chemical industries, metallurgy and smithy factories, etc. make use of polarization of radiations to carry out tests for stress and pressure analysis of objects. One of the most common testing procedures used by such industries includes optical stress analysis. Optical stress analysis makes use of plastic models to determine the regions of potential weaknesses of the material. When the material is put under stress, a stress pattern is formed that contains various bands of light and dark colour. The image of the stress pattern is generally formed with the help of polarizers.
5. Seismology
Seismology or the study of the nature of earthquakes make use of polarization of radiations to determine the magnitude of an earthquake. It also helps scientists and researchers to make an attempt and predict the occurrence of a similar earthquake in the near future.
6. Chemistry Laboratories
A number of testing and experiment procedures that take place at chemistry laboratories make use of the polarisation of radiations. For instance, the process of testing the chirality of the organic compounds mainly works on the principle of polarization.
