Which phenomenon is used in Optical Fiber Cable?

The correct answer is Total internal reflection.

Important Points

Total Internal reflection:

• The total reflection of light from a higher refractive index medium to back in its medium at an angle more than a critical angle known as total internal reflection.
  • It always happens when light travels from denser medium to rarer medium.

• Optical fiber: It is a very thin fiber made of glass and plastic having a radius of the order of a micrometer (10-6 m).
  • It works on the principle of Total Internal Reflection.
  • It is lightweight, fast, and useful for long-distance data and light transmission with very few losses.
  • A bundle of such thin fibers forms a light pipe.

Additional Information

• Scattering of light: The phenomenon in which the particles in a colloid scatter the beams of light that are directed at them is called scattering of light.
• Refraction: When a ray of light passes from one medium to another it suffers a change in direction at the boundary of two media is called refraction.
• Reflection: The phenomena in which light ray is sent back into the same medium from which it is coming, on interaction with boundary, is called reflection.