Highly sensitive curvature and displacement sensing setup based on an all fiber micro Fabry–Perot interferometer

A highly sensitive curvature and displacement sensing arrangement based on an all optical fiber micro Fabry–Perot Interferometer (MFPI) is presented. Here, the MFPI spectral fringes contrast is decreased due to curvature effects occurring within a segment of single mode fiber (SMF). Therefore by detecting optical power variations, at certain wavelengths, it was possible to determine curvature and displacement changes. For this setup the achieved curvature sensitivity was 0.3 dB/m−1 and the curvature resolution was 31.5×10−3 m−1. Finally some experimental results are provided to support the viability of this low cost sensing arrangement.