Recent Advances in Fiber Cavity Ring-down Technology

Abstract

A brief review in the fibre cavity ring-down (CRD) technique is presented. It addresses the latest developments in CRD technique for sensing applications, undergone at INESC TEC. The CRD is based on the conventional configuration with the possibility of adding amplification in order to compensate the output signal losses induced by the sensing head. The results obtained for strain, curvature and refractive index sensing are presented, corresponding to distinct sensing structures, namely, a chirped fibre Bragg grating (FBG), a long period grating (LPG) and a multimode interference (MMI) based sensor.