Polarized Light vs Unpolarized Light
Polarization is a very important effect discussed in wave theory of light. The effect of polarization is rarely observed in real life situations, but this is very useful in studying the characteristics of light. It is vital to have a proper understanding in the effect of polarization, polarized light and un-polarized light in order to excel in fields such as modern and classical optics, waves and vibrations, acoustics and various other fields. In this article, we are going to discuss what polarization is, what polarized light and un-polarized light are, their definitions, the variations of polarized light, the applications of polarization, and finally the difference between polarized light and un-polarized light.
For one to understand polarized light, he/she must first understand polarization. Polarization is simply defined as a type of orientation of oscillations in a wave. Polarization of a wave describes the direction of oscillation of a wave with respect to the direction of propagation; therefore, only transverse waves display polarization. The oscillation of particles in a longitudinal wave is always in the direction of propagation; therefore, they do not display polarization. There are three types of polarization, namely linear polarization, circular polarization, and elliptical polarization. Imagine a wave travelling through space. If the wave is a mechanical wave, particles get affected by the wave and oscillate. If the particles oscillate on a line perpendicular to the direction of propagation, the wave is said to be linearly polarized. If the particles trace out an ellipse on a plane perpendicular to the movement of propagation, the wave is an elliptically polarized wave. If the particle traces a circle on a plane perpendicular to the direction of propagation, then the wave is said to be circular polarized. The process of polarizing is done using a polarizer. A polarizer is a device that only allows some fraction of the wave pass through it.
Un-polarized light is the light we generally see daily. Any source of light generated as photons have random directions of oscillations with respect to the direction of propagation. Un-polarized light has intensity components at every direction, at all times. If un-polarized light is sent through a polarizer, polarized light can be obtained. Reflection also causes a partial linear polarization in the direction parallel to the reflected surface. Polaroid glasses are used to polarize light in daily lives. Since the light reflected only has the horizontal electrical component in prominence, the Polaroid glass cuts the horizontal intensity.
What is the difference between Polarized and Un-polarized Light?
• Un-polarized light has electrical component in every direction, at any given time, but the polarized light has the electric component only in one direction for a given time.
• When the un-polarized light is polarized, it is always reduced in intensity.
• Light sources give out un-polarized light, but it is impossible to create polarized light sources without the usage of a polarizer.