Can optical fibers be used as sensors?

Question

Olivia Askew · Accepted Answer

Yes, as extrinsic sensor EFOS or intrinsic sensor IFOS.

You can have an idea from a fundamental paper:

in which are described Extrinsic sensors where the fibre acts as a simple light channel, such as in a proximity sensor, where light scattered from an obstacle is collected by a fibre and sent to a detector for distance measurements:

As an Intrinsic sensor you use the fibre to sense the environment through a change in its property caused by something such as pressure; for example, pressing on a section of fibre causes its refractive index to change and as a consequence light emerging from it will show changes (compared to not affected light from a second fibre):

Adrian Ayala · Answer

undefined Yes, optical fibers can be used as sensors. They can detect various physical and chemical parameters such as temperature, pressure, strain, pH, and chemical concentrations by exploiting changes in the properties of light traveling through the fiber. This is achieved through mechanisms such as fiber Bragg gratings, interferometry, and evanescent wave absorption. Optical fiber sensors offer advantages such as high sensitivity, immunity to electromagnetic interference, and the ability to cover long distances without signal degradation.