We conducted experiments and theoretical calculations on the characteristics of Air probes/Transducers used in Non-Contact Air Coupled Ultrasonic Testing (hereinafter referred to as NAUT) using ultra-high power square burst waves.
It was found that the beam is focused and a clear high-resolution image can be obtained by using the point focusing probe/transducer.
You can download the characteristics of the probe/transducer of NAUT system and example of application from the blue link at the bottom.