A single-mode fiber sensor for the detection of laser-induced ultrasonic in a metal

Modeling the ultrasound is critical for characterizing the physical propert y of the materials. In this paper, a novel single-mode optical fiber ultras onic sensor based on ultrasonic pulses induced fiber birefringence is desig ned to measure the longitudinal wave signal generated in copper by a pulsed Nd:YAG laser. Experiments have proved that this sensor has a wide band and high sensitivity. From the waveform captured by the oscillator. thickness of the sample plates can be measured with uncertainty less than 5%. Good ag reements between theoretical and experimental results are obtained.