Ultrasonic Sensor Using Polarization-Maintaining Optical Fiber

The interaction between acoustic wave and the laser light passing through an optical fiber has been studied by several workers.1)-4) The detection of acoustic wave using an optical fiber carried out5)6), also. The receiving sensitivity of optical fiber hydrophone is determined by the rate of change in the optical path length of the sensing fiber with respect to changes in the external pressure on the fiber. These changes in the optical path length are results of the induced changes in index of refraction of the fiber and changes in the length of the fiber. There are the hydrophone of an interference using two optical fibers and a non-interference using a polarization-maintaining optical fiber. In this paper, an ultrasonic sensor using a polarization-maintaining optical fiber based on a. non-interference has been studied.