Optical Fibres

Optical fibres are used in medical endoscopes to see inside the body, and in communications to carry light signals. The light ray in a optical pfibre is totally internally reflected each time it reaches the fibre boundary, even when the fibre bends unless the radius of the bend is too small. At each point where the light ray reaches the boundary, the angle of incidence exceeds the critical angle of the fibre.

A communications optical fibre allows pulses of light that entre at one end, from a transmitter, to reach a receiver at the other end. Such fibres…