Innovative Optical Nanocomposite Sensor for Security Systems Innovative Optical Nanocomposite Sensor for Security Systems

In this work, we propose a new concept of optical tactile pressure sensing applied to flexible gold/PDMS nanocomposite material. We develop an optical tapered fiber force sensor based on electromagnetic (EM) coupling effect. The light coming from a tapered multimode Si fiber is coupled to a PDMS-Au polymer film. The formed gold nanoparticles increase the effective refractive index of the PDMS and support the EM coupling with the tapered region by applying a weight that can be translate to pressure forces to the sensor. After an accurate characterization of the PDMS-Au material by the atomic force microscopy (AFM) technique, we experimentally observe in real time the intensity reduction of the transmittivity response at the output of the fiber sensor due to an applied weight. The proposed sensor is suitable for security systems able to detect undesired intrusions.