Optical measurement of guided waves

This paper demonstrates an optical method for measuring guided waves in plates that is much faster than traditional scanning approaches. By recording the wavefield with a high-speed camera and applying a post-processing method, the wavefield can be extracted from the static and noise components within the measured signal. This technique is demonstrated with a transient wave in a fiber-glass plate. A comparison of the wavefield is made to data measured with a scanning laser Doppler velocimeter (SLDV). Good agreement is found between the measurements from the optical technique and the SLDV.