Dynamical interrogation of interferometric sensor arrays by a simple polarimetric setup

Numerous methods have been proposed for multiplexing interferometric sensors into large scale arrays. Previously we described a low loss polarimetric sensor array based on a concatenation of high-birefringence fiber. It was interrogated by a wavelength scanning laser and its output was measured by a polarization analyzer. Here we demonstrate how the same source and detection system can be used to interrogate a different sensor array with increased sensitivity: a cascade of fiber-optic Fabry-Perot interferometers. The auxiliary interferometer, needed for obtaining a synchronized linear frequency grid, is implemented "in-line" and does not require an additional detection and digitizing circuitry. The proposed approach, therefore, constitutes a simple and modular sensor array interrogation scheme in which different arrays of sensors with significantly different sensitivities can be interchanged according to circumstances.