Scanning acoustic tomography

This technique is also known as scanning acoustic tomography. This is a powerful tool for spotting delaminations, cracks, and other anomalies non-destructively. Not only does acoustic microscopy detect the failures but it can also provide the specific location of the problem. SAM high-resolution images and advanced diagnostic tools are used to ... 

Fig. 14. Inspection of the delamination between Si diip and encapsulant by SEM and SAT (Scanning Acoustic Tomography) ...

Optical coherence tomography (OCT) is similar to ultrasound, except that light, rather than acoustic vibrations, are used as the signal source. Like ultrasound, an image can be composed from scans of light reflected from tissue interfacial boundaries. OCT has better resolution than MRI or ultrasound, and there is no ionizing radiation or special tissue sample preparation involved. 

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