Functionalized Optical Fibre Sensors for Real-Time Environmental Monitoring Applications

Abstract

The role of optical fibres as a medium for information transfer has found many applications. One of these is in environmental sensing, where slight perturbations in the surrounding environment can be remotely detected through modulation of light at selected points along the optical fibre. These perturbations exist in the form of variations in refractive index (RI), temperature or strain. This paper reviews our recent work on optical fibre-based RI sensors, in particular long period fibre gratings (LPFGs), integrated with carbon nano-materials. These carbon nano-materials with their unique properties modified the sensing scheme of the conventional fibre sensors, allowing them to gain immunity from certain free spectral range limitations, extend their operation range and also present the potential for efficient real-time environmental monitoring applications.