Question

• Explain why light is trapped in an optical fiber.
• Describe at least two cases where you have observed the effects of light refraction besides the case of a swimming pool.
• Why the fabrication of optical fiber is a very delicate process?
• What do you understand is the "Dispersion" effect in communication fibers

Answer 1

*Explain why light is trapped in an optical fiber.

A)Light is trapped in an optical fiber becasue of "Total Internal Reflection". •The angle of entry θ₀ for light entering a fiber determines whether the light is guided by the fiber. Angles of entry less than the cut-off angle θ_0max result in light staying in the fiber.

*Describe at least two cases where you have observed the effects of light refraction besides the case of a swimming pool.

1.Formation of rainbow: first the refraction of sunlight and then scattering of the beam.

2.Twinkling of stars is due to the refraction of light.

3.lens on your smartphone camera

•Why the fabrication of optical fiber is a very delicate process? Reason:

Optical fibers are fabricated in a multi-step process: preform fabrication, fiber drawing, fiber coating, and spooling.

During fiber deawing stage,the end of the preform is lowered into a furnace heated to roughly 3,632°F (2,000°C). The tip softens until it is drawn down by gravity, shrinking in diameter. Sensors constantly monitor the fiber diameter and concentricity to assure optimal results.

Hence,the fabrication of optical fiber is a delicate process

•What do you understand is the "Dispersion" effect in communication fibers.

Dispersion is spreading of light when it pass through optical fiber.   

This phenomenon is due to the fact that speed of light depends on its wavelength and propagation mode.

I hope the answer is clear.Thank you