Abstract: The traditional ultrasonic focused transducers are always utilizing single piezoelectric sensor as receiver, and the received signal is the integral of the reflection of acoustic field at the piezoelectric material, but it can’t reflect the characteristics of reflected acoustic field. So that a new approach is presented which excitation and reception are separated to design and fabrication of array-analytic ultrasonic focused transducer. Using a multi-sensing element as receiver by a high-speed ultrasonic testing system based on FPGA technology to collected signals from different angles and analyzed these signals. Firstly, the approach of the design and manufacture of array-analytic ultrasonic focused transducer is expound and the multiple characteristics of excitation and response of the transducer array are calibrated. Secondly, the received multi-angle acoustic field signals are analyzed and processed by using the spatial distribution characteristics of the new type of transducer’s array sensing elements. Finally, the experimental research carries on the object of the different heights of the stairs sample by the approach of spatial-sensing acoustic field measure and the expected result has been achieved. That is build up a good basis for irregular crack defect detection.

Key words: array-analytic, reflected acoustic field, spatial-sensing, ultrasonic focused transducer