Tomographic imaging based on scanning acoustic microscopy

In the majority of cases the term "tomography" is associated with computed X-ray tomography. However several other physical interactions also have the ability to provide information from the inside of objects. Already traditional scanning acoustic microscopy (SAM) gives volume information for opaque materials. However, for most defect types in a homogeneous material the SAM C- and B-Scans alone do not give a correct volume image. Algorithms processing data from different scan positions improve the situation significantly. But only when a number of additional measures are taken satisfactory results can be obtained. After describing the basic principles of SAM tomography an example of application is given and the results are compared to X-ray tomography (CT) of the same object.