Explain, with the aid of a labeled diagram, how a ray of light is guided along a fiber.
An optical fiber consists of a glass pipe coated with a second material of lower refractive index.
5. Light enters one end of the fibre and strikes the boundary between the two materials at an angle greater than the critical angle, resulting in total internal reflection at the interface.
6.This reflected light now strikes the interface on the opposite wall and gets totally reflected again.
7. This process continues all along the glass pipe until the light emerges at the far end.