Abstract

Self-mixing interferometry allows detecting static and dynamic strain, whereas a laser source is perturbed by a moving target which backreflects part of the optical input power [1-2]. Both free-space and in-fiber systems operate in low-feedback conditions. This paper proposes to extend the self-mixing operation to chaotic conditions, using a dually distributed cavity: a distributed feedback (DFB) laser is connected to a 95% reflective fiber Bragg grating (FBG), which acts as a distributed reflector. The FBG is perturbed with static and dynamic strain, changing its reflectivity at the DFB wavelength.

© 2013 IEEE