Fibre optic sensors are a type of proximity sensor that have an optical fibre connected to a light source to allow for detection in tight spaces or where a small profile is beneficial. The optical fibre is a transparent fibre made of glass (silica) or plastic with a diameter slightly thicker than a human hair, this fibre transmits light between the two ends to produce an electrical signal.
A fibre-optic sensor system is a technology that consists of a fibre-optic cable connected to a remote sensor, or amplifier. The sensor emits, receives, and converts the light energy into an electrical signal. The optical cable is the mechanical component that transports the light into and out of areas that are either too space constrained or too hostile back to the sensor.
Fibre optic sensors are used in a number of different sensing applications. In mechanical properties testing, fibre optical sensors are used to measure mechanical strain. They can also be used to measure acceleration, velocity, pressure, temperature and displacement.