Blog : What's new ?

Developers and researchers from the CIVA development team have developed a new imaging technique combining the individual benefit of the medical PWI (Plane Wave Imaging) and of the TFM (Total Focusing Method).

How does it work?

Plane waves are used in transmission and then a post-processing algorithm is applied to the recorded signals  that lets you focus on every point of a region of interest. This method allows you to obtain an image quality equivalent to TFM images but with a higher frame-rate, increased acoustic power and simplified post-processing algorithm. 

This method is described in detail in a paper of the Ultrasonics Journal from Elsevier. You can download it here.

The EXTENDE’s team

Ed Ginzel, retired consultant with Materials Research Institute, active member of the NDT.net community and CIVA user, explains in a technical tip  why a focused beam should not be used for general weld inspection.

His demonstration based on CIVA simulation can be downloaded here. It shows that the increase of sensitivity due to focusing is done at the expense of reducing sensitivity in the weld/HAZ zone, thereby requiring the operator to use more receiver gain in the TCG construction in the region of interest. As a result of the increased beam spread that occurs after the focal point, there is reduced beam resolution.  Therefore, closely spaced indications are more difficult to resolve.

This tip is open to discussion in the NDT.net forum. Don’t hesitate participating!

The EXTENDE's team