SAFT Applied to Anisotropic and Attenuative Materials Using Sparse Array Data and Signal Processing

Improved SAFT imaging methodologies are discussed for the inspection of composite materials and coarse‐grained polycrystalline materials. The problem of unfavourable beam fields of conventional transducers, which occurs for specific elastic material properties, is solved by using a two‐dimensional array for beam focusing and steering. Additionally, redundant sets of rf‐data are acquired and used for image reconstruction by exciting the transmit and receive elements, respectively, in variable subsets, revealing the promising potential of sparse array applications.