All-fiber optical interferometer with nonlinear control for accelerometers

Abstract

Optical fiber sensors based on interferometry can be applied in aeronautics and space applications, due to the typical lightweight and high sensitivity. They may be inertial sensors, such as fiber optic gyroscopes based on the Sagnac effect and fiber optic accelerometers based on fiber Bragg gratings. An optical interferometer is capable of measuring very small light phase variation by the phenomenon of light interference. However, due to its high sensitivity the interferometer is very susceptible to spurious disturbances, such as temperature variation or mechanical vibrations and, therefore a feedback signal is required to control the unwanted variations in the interferometric signal. In this work, an all-fiber optical interferometer with nonlinear control will be developed and set to work as an accelerometer for space applications. (AU)