Concepts

Optical Fibre

CAPF wiki1 min read7 sections
At a glance
SubjectScience

Definition

A thin, flexible strand of glass or plastic that carries information as pulses of light along its length, working on the principle of total internal reflection.

Key points

  • Light enters one end and bounces along the fibre by total internal reflection, staying trapped inside with very little loss, even around bends.
  • A fibre has a central core surrounded by a cladding of lower refractive index, which keeps the light confined to the core.
  • Optical fibres carry data as light pulses, offering very high bandwidth, high speed, low signal loss, and immunity to electrical interference, far better than copper wires.
  • They form the backbone of the internet, telephone networks, and cable television, and are used in medical endoscopes and in sensors.
  • In India, the BharatNet project aims to connect village panchayats with optical-fibre broadband, supporting digital connectivity (verify the latest coverage).

Why it matters for CAPF

Optical fibres, their reliance on total internal reflection, their advantages over copper, and projects such as BharatNet are recurring information-technology and physics facts, with a secure-communications angle.

Common confusion

Optical fibre carries light, not electricity, which is why it is immune to electromagnetic interference; it is not simply a thin copper wire. It works by total internal reflection within the fibre, not by ordinary reflection from an outside mirror.

One-line recall

Glass or plastic strands that guide light by total internal reflection to carry high-speed data with low loss; the backbone of the internet and the BharatNet rollout.

concept total internal reflection, concept lasers, concept electromagnetic spectrum

Parent note

information technology and computing

← BackAll of Concepts