Fiber-optic voltage sensor using fiber gyro technology

The technique of non-reciprocal optical phase modulation known from fiber gyroscopes is adapted to interrogate a polarimetric optical voltage sensor. The piezoelectric deformation of a transducer by an applied ac voltage is transmitted to a birefringent fiber resulting in a periodic phase shift of the two orthogonal polarizations of the fundamental fiber mode. A modulator at the detector end of the sensor introduces a nonreciprocal phase modulation of the light waves. The voltage is recovered from the first and second harmonics of the modulator frequency and side bands in the detected signal. (C) 2010 Published by Elsevier Ltd.