When the TriO transducer is use in the PWO mode, the evolution of the shape of the signal versus the range is much less important than with a conventional uniform transducer and the duration of the signal is much shorter. In the near and mid field, the possibility of discrimination of defects close in range is much enhanced.

A conventional focused transducer produces optimal focusing over the short length of the so-called "useful beam". On the contrary, when the TriO transducer is used in the EWO mode, it produces an optimal focusing at every distance on a wide range. As compared to a usual focused transducer, its lateral resolution is better, but its sensitivity is lower.

At long ranges, no particular interest has been found in using the non-uniform transducers. TriO can then be used as a conventional uniform transducer.

This probe does not require specific electronic equipment.

Recently we have applied the same concept to focused probes. Calculations and experiments show that the focused Edge Wave Only mode is the most interesting. The properties of the focused EWO transducer are intermediary between those of the focused transducer and the Edge Wave Only mode of TriO.