Novel Fiber Bragg Grating Accelerometer Based on Diaphragm

We present the modeling, design, fabrication, optimization, and characterization of a novel fiber Bragg grating (FBG) accelerometer based on a diaphragm. The principle of the FBG accelerometer and the acceleration response versus FBG wavelength are analyzed theoretically. Experimental results indicate that the FBG accelerometer provides a linear response over a broad frequency range from 10 to 200 Hz, with a high sensitivity of 36.6 pm/G, which agrees well with the theoretical sensitivity; linear fitting is 99.8% and relative error is 3.68%. Dynamic resolution is 2 ${\rm mG}/\sqrt {\rm Hz}$ in flat range, cross-axis sensitivity less than 1.3% of the main-axis sensitivity, and it has a strong anti-interference capacity, so it is a good candidate for cross well seismic wave measurement $({>}{\rm 50}~{\rm Hz})$ .