Characteristic research on focused acoustic field of linear phased array transducer

Using pulse-echo method, the defects of inspected specimens, such as cracks, inclusions, porosities, can be tested with ultrasonic phased array technique. Phased array transducer can realize the conversion between sound wave and electric signal, its characteristic of acoustic field is the most important factor whether the echo information of the inspected area in a specimen can be obtained and utilized effectively, and it is the main basis of designing a phased array. In this paper a mathematical model was presented to simulate the characteristic of focused acoustic field radiated from an ultrasonic linear phased array on the basis of the Huygens´ principle. Based on the model, studies on beam focusing directivity were conducted by analyzing the effects of various transducer parameters systematically. Finally, the designing principle of linear array transducer was given.