Focusing in solids and application in acoustic imaging

来源 :Chinese Journal of Acoustics | 被引量 : 0次 | 上传用户:nicolaskerry
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Focusing in solids by surface transducer arrays(STA)and the acousticfield distribution on the focal axis are studied in this paper.The relation betweenthe source element width and the field strength at different order focuses is alsodiscussed.Numerical calculation is used to get the focal field distribution as theelement width is changed.Some practical problems such as the minimumdistinguishable frequency,the transversal and longitudinal resolution are investi-gated when this kind of focusing is used for NDT and acoustic imaging.Someexplorative experiments have been done to demonstrate the theory. Focusing in solids by surface transducer arrays (STA) and the acousticfield distribution on the focal axis are studied in this paper. The relation betweenthe source element width and the field strength at different order focuses is alsodiscussed. Numerical calculation is used to get the focal field distribution as theelement width is changed.Some practical problems such as the minimum distinguished frequency, the transversal and longitudinal resolution are instisti-gated when this kind of focusing is used for NDT and acoustic imaging. Someexplorative experiments have been done to demonstrate the theory.
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