TIR + Optical Fibres- lec 3 revision series

Optical fibre are based on

Statement-I : Optical fibres are free from electromagnetic disturbances Statement-II : Optical fibres are electrically insulated.

In an optical fibre, the light signal is transmitted by

Optical fibre communication uses the frequency range of

Assertion : Optical fibres make use of total internal reflection. Reason : Light undergoes successive total internal reflections as it moves through an optical fibre.

The optical fibres have in an inner core of refractive index n1 and a cladding of refractive index n2 such that

The glass of optical fibre has a refractive index 1.55 and cladding with another glass of refractive index 1.51. When the surrounding medium is air, the numerical aperture will be

The intensity of a light pulse travelling along an optical fibre decreases exponentially with distance according to the relation l = i_(0) e^(-0.0693x) where x is in km and l_(0) is intensity of incident pulse. The intensity of pulse reduces to (1)/(4) after travelling a distance

The diameter of an optical fibre is

the attenution in optical fibre is mainly due to