Application of Matrix Array Transducer for Non-destructive Photoacoustic Imaging

Abstract

In general, it is challenging to evaluate subsurface flaws of a target material because of a dead zone of surface echo in nondestructive ultrasonic testing. In this study, photoacoustic (PA) imaging using a matrix array transducer was applied to reconstruct the three-dimensional shape of subsurface flaws in carbon fiber reinforced plastic (CFRP). The matrix array transducer can receive the scattered signal individually and enhance the total intensity by setting a delay for each element. In this study, we selected several focal depths and reconstructed the flaw shape using the synthetic aperture focusing technique. The result showed that adequate delay design was necessary for accurate flaw imaging.