A Self-Referencing Intensity Based Polymer Optical Fiber Sensor for Liquid Detection

David Montero,Ingo Möllers,Jon Arrúe,Carmen Vázquez,Dieter Jäger

doi:10.3390/s90806446

David Montero, Ingo Möllers + Show 3 more

Open Access

https://doi.org/10.3390/s90806446

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Abstract

A novel self-referencing fiber optic intensity sensor based on bending losses of a partially polished polymer optical fiber (POF) coupler is presented. The coupling ratio (K) depends on the external liquid in which the sensor is immersed. It is possible to distinguish between different liquids and to detect their presence. Experimental results for the most usual liquids found in industry, like water and oil, are given. K value increases up to 10% from the nominal value depending on the liquid. Sensor temperature dependence has also been studied for a range from 25 °C (environmental condition) to 50 °C. Any sector requiring liquid level measurements in flammable atmospheres can benefit from this intrinsically safe technology.

Highlights

Polymer Optical Fibers (POFs) have been widely used in industry and automotive networks
In the optical sensing field, POFs are experiencing a big growth because they present numerous advantages such as easier handling and lower cost compared to glass optical fibers. These are some reasons why new POF sensors have appeared and are still appearing, most of them based on optical power intensity detection
This paper shows a representative example that demonstrates the capabilities of sensors based on polymer optical fibers in home networks for measuring liquid levels in harsh environments such as oil/petrol tanks or bio-mass boilers to be used in condominiums and buildings

Summary

Introduction

Polymer Optical Fibers (POFs) have been widely used in industry and automotive networks. In the optical sensing field, POFs are experiencing a big growth because they present numerous advantages such as easier handling (more flexibility) and lower cost compared to glass optical fibers These are some reasons why new POF sensors have appeared and are still appearing, most of them based on optical power intensity detection. In this paper a novel self-referencing intensity-based polymer optical fiber sensor for liquid detection is presented. This paper shows a representative example that demonstrates the capabilities of sensors based on polymer optical fibers in home networks for measuring liquid levels in harsh environments such as oil/petrol tanks or bio-mass boilers to be used in condominiums and buildings. The work includes novel device, theoretical study and experimental results

Principle of Operation and Simulations

Sensor Measurements

Sensor Temperature Dependence

Findings

Conclusions