Liquid level measurement based on multi-S-bend plastic optical fiber

This paper aims to propose a liquid level sensor with a multi-S-bend plastic optical fiber.

The principle of liquid sensing used is based on the leakage of higher modes out of the fiber and repeated regeneration in the following bend sections. Therefore, a propagation loss was introduced in every bend section of the fiber with the loss depending on the refractive index of the environment.

Therefore, a continue shift in the liquid level can be detected by observing changes in the propagation loss of the fiber. The sensor features compactness and a flexible resolution.

Compared with the exited ones, the sensor has capability of continue liquid measurement and a greater measurement range.