Focusing in solids by surface transducer arrays ( STA ) and the acoustic field distribution on the focal axis are studied in this paper. The relation between the source element width and the field strength at differen...Focusing in solids by surface transducer arrays ( STA ) and the acoustic field distribution on the focal axis are studied in this paper. The relation between the source element width and the field strength at different order focuses is also discussed. Numerical calculation is used to get the focal field distribution as the element width is changed. Some practical problems such as the minimum distinguishable frequency, the transversal and longitudinal resolution are investigated when this kind of focusing is used for NDT and acoustic imaging. Some explorative experiments have been done to demonstrate the theory.展开更多
文摘Focusing in solids by surface transducer arrays ( STA ) and the acoustic field distribution on the focal axis are studied in this paper. The relation between the source element width and the field strength at different order focuses is also discussed. Numerical calculation is used to get the focal field distribution as the element width is changed. Some practical problems such as the minimum distinguishable frequency, the transversal and longitudinal resolution are investigated when this kind of focusing is used for NDT and acoustic imaging. Some explorative experiments have been done to demonstrate the theory.