Its is the phenomenon in which ray of light travelling at an angle of incidence greater than critical angle from denser to rarer medium is totally reflected back to same medium.
Conditions of Total Internal Reflection?
Following are the two conditions of total internal reflection:
- The light ray moves from a more dense medium to a less dense medium.
- The angle of incidence must be greater than the critical angle.
Applications
Diamond:
When the incident ray falls on every face of the diamond such that the angle formed, the ray is greater than the critical angle. The critical value of the diamond is 23°. This condition is responsible for the total internal reflection in a diamond which makes it shine.
Mirage:
It is an optical illusion that is responsible for the appearance of the water layer at short distances in a desert or on the road. Mirage is an example of total internal reflection which occurs due to atmospheric refraction.