Introduction

Optical Fiber
It is a glass filament or wire which carries light.
It is a cylindrical waveguide that operate at optical frequency.
It confines electromagnetic energy in the form of light.
COMMUNICATION
It may be broadly defined as the transfer of information from one point to another.
History
Hollow Logs, Drum (different sizes), Wind Instruments (pipes), Smoke Signals, Signal fires and Signaling lamps.
The first optical fiber exhibited very high attenuation i.e. 1000 dB/Km. While coaxial cable losses were 5-10 dB/Km.
Fiber losses were reduced to below 5 dB/Km.
Development of fiber waveguides with optical frequencies at small wavelengths requires the development of all optical components.
Laser Life at the start was 1000 Hrs & now is 100 years.
At present two optical windows are in operation i.e. 1310 nm ,1550nm.