本論文製作一有別於傳統聚焦式超聲波換能器之新型解析式背向散射陣列換能器。傳統聚焦式超聲波換能器是將整個感測面積接收到之所有聲波做積分才能得到一個單一的輸出信號，此一信號無法完整的反應出背向散射聲場。因此，本論文以P(VDF-TrFE) 為壓電材料製作一解析式背向散射陣列換能器，利用低成本且快速的黃光微影方式，在石英鏡柱之內凹曲面佈上多個小面積之感測元件，不同位置上之感測元件可接收來自不同方向之散射聲波訊號並各別獨立輸出，使得散射聲波可被更有效的解讀。同時以此解析式換能器量測不同平面之入射聲場資訊，並利用角頻譜理論計算入射聲場，兩者比對證明可成功地預測入射聲場資訊；在反射聲場的部分，搭配角頻譜理論則可預測出不同試材下，各感測元件接收到之訊號振幅趨勢。最後，整理圓柱與圓球的散射理論，並以解析式陣列換能器量測不同尺寸及材料的圓柱與圓球之散射聲壓分布。將量測與散射理論計算進行比較，證實可得到相同的散射聲壓分布趨勢。

This study fabricates a newest analytic back scattering array transducer that is different from conventional focusing transducer. Conventional focusing transducer just get one voltage signal by integrating all the signal which received from whole sensing area, and this voltage signal cannot show the complete back scattering acoustic field. On this background, this study making an analytic back scattering array transducer which using P(VDF-TrFE) as piezoelectric material, and the tech of photo lithography which is low-cost and fast is used for making the sensing element on the concave of quartz, the sensing element on the concave of different location that can receive the signal from all direction, making the scattering signal come from substrates be analyzed effectively. In experiment part, measuring the distribution of the incident acoustic field by using this transducer, and angular spectrum approach is used for predicting the incident acoustic field that compare with the experimental part, the result shows that angular spectrum approach do well in predicting the incident acoustic field. In addition, angular spectrum approach also used for predicting the voltage signal of each sensing element that received come from different substrates, and it is in good agreement with the experiment. In application, measuring the scattering field of cylinder and sphere with different size and material, then compared with the simulation using scattering theory, and the result shows that the measuring has the same tendency with the scattering theory.

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