Total internal reflection of light radiations is the phenomenon by virtue of which light radiation arriving at the interface or boundary of two different mediums is able to get completely reflected inside the medium and does not suffer any refraction, transmission, diffusion, scattering, or other relevant phenomena. Here, the ray of light is not able to escape and enter the second medium, but instead, it tends to get reflected back into the first medium itself. As a result, the ray of light gets trapped inside the internal structure of the medium. The phenomenon of total internal reflection is generally observed in electromagnetic waves, sound waves, and water waves.
Examples of Total Internal Reflection
1. Sparkling of Diamond
The sparkling of a diamond is a classic example of the total internal reflection phenomenon in real life. The light that enters the structure of the diamond is made to strike its surface at an angle greater than the critical angle of reflection, hence the ray of light is not able to escape the structure of the diamond and stays inside for long. This creates a glittery and shining appearance of the diamond.
2. Optical Fibre Communication
The basic working principle of optical fibre communication depends on the total internal reflection of the incident light wave. To achieve a total internal reflection of the light radiation that contains the information and the message, typically two techniques are employed. The first technique is to increase the angle of incidence above the critical angle value, while the second technique is to increase the refractive index of the cladding by a significant amount as compared to the refractive index of the core.
3. Formation of Mirage
Usually, during the daytime, a water layer appears to be present on the surface of the road or on the sand surface of the deserts, known as a mirage. A mirage is nothing but a type of optical illusion that is generally observed in the deserts or on the surface of hot roads. The formation of mirage is typically based on the total internal reflection of light waves.
Prisms are one of the most common objects used in our daily life that are capable of displaying the total internal reflection phenomenon in one of the easiest manners. For this purpose, generally, the right-angled isosceles prisms, equilateral prisms, or right-angled prisms are preferred.