A novel laser ultrasonic sensor for testing thickness

摘要

A new laser ultrasonic sensor for testing samples' thickness is developed. This sensor has high-frequency response and high sensitivity. Furthermore it is easy to adjust. When the sensor is used to focus on polished iron plate, well-defined longitude-wave and its echo waves can be obtained. Based on the experimental results, the sample's thickness can be deduced. The theoretical and experimental results are in good agreement with relative error of 0.5%.