Silicone embedding of fiber Bragg gratings for physiological sensing

Embedding fiber Bragg gratings (FBGs) in flexible matrices like silicone, plastic, and rubber is gaining prominence in healthcare aiming to develop increasingly wearable and comfortable sensors of a variety of physiological parameters, from heart rate to joint movements. In this scenario, this work proposes the FBG embedding in silicone devices for two main purposes, i.e., arterial plethysmography and finger tapping monitoring. The fabrication process of the two developed sensors is described and the preliminary obtained results are reported and discussed. Besides providing flexibility, FBG embedding allows to improve the pressure sensitivity and protect the optical fiber sensor from the external stress. The developed sensors result to be skin compatible, non-invasive, and easy to use.