Can optical fibers be used as sensors?

1 Answer
Sep 22, 2015

Yes, as extrinsic sensor EFOS or intrinsic sensor IFOS.

Explanation:

You can have an idea from a fundamental paper:

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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:

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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):

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