本文將提出一種以積層設計的方式來改變壓電式揚聲器進而優化其音頻響應，以積層式的方式可以降低驅動電壓，提高壓電揚聲器的位移及聲壓，由於數位電視的薄型化以及行動電話的進步迅速，薄型揚聲器應運而生，但壓電揚聲器的音頻響應起伏太大，所以本文的目標為改善其音頻響應。
首先利用有限元素法對壓電揚聲器的不同厚度作模態、共振頻率及位移分析，並與自製燒結之壓電揚聲器得到一致性的結果。接著製作積層式壓電揚聲器及比較碳纖維振動板厚度對聲壓的影響，然後結合碳纖維振動板組裝成壓電式平板揚聲器。利用有限元素法對振動板作模態分析，將模態中的節點位置找出，設計陣列擺放位置，透過陣列的方式改善壓電揚聲器的音頻響應。
最後本文達到第一共振頻率降低191Hz，平均聲壓提高17.7dB，且改善中音谷現象，未來將能使此種具體積輕薄與高效率之積層式壓電揚聲器廣泛應用在各類視聽產品上。

An effective structural multilayer for a piezoelectrical speaker with improved frequency response is proposed in this thesis. The piezoelectrical speaker can improve the displacement and sound pressure level, and reduce the driving voltage by using multilayer. For supporting the development of thinner digital TVs and faster progress of cell phones, thinner speakers were produced. Because piezoelectrical speakers are characterized by sharp peaks on the frequency response, the aim of this thesis is to improve frequency response.
First, we analyzed mode shapes, resonant frequency and displacement for piezoelectric speakers sintered by ourselves with different thickness using Finite Element Method. We made multilayer piezoelectrical speakers, and analyzed the thickness of carbon fiber plate which influence the sound pressure level. Then a combination of carbon fiber plate assembled piezoelectrical panel speaker. The Finite Element Method analysis of the plate was conducted to find out mode shapes and their corresponding node positions, and frequency response of the piezoelectrical speaker can be improved throught array design.
Finally, the first resonant frequency was reduced 191Hz, the average sound pressure level increased 17.7dB, and improved the mid-frequency dip. The applications of this high potential and miniaturizable multilayer piezoelectrical speaker can be extended through this improvement.

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