拉福波是在彈性體上成長一波導層，以水平剪向波的傳遞方式。其傳遞時大部分的能量皆集中在波導層附近，因此其波傳特性不僅和聲波所在介質有關，也受彈性體表面及波導層邊界條件影響。拉福波液體感測器即是利用此原理，藉由分析液體負載對波速、波傳衰減常數等波傳特性造成的變化來求得未知液體的各項特性參數。
　　本論文針對石英(Quartz)、鈮酸鋰(LiNbO3)及鉭酸鋰(LiTaO3)等常用單晶壓電材料的拉福波波傳特性進行探討，將理論推導以數值分析方法配合電腦程式的撰寫求得各材料在不同波導層、不同傳播方向時聲波之波速、機電耦合常數；進一步並探討液體負載的導電度及黏滯度等參數對表面聲波波傳特性的影響。
　　最後比對別人的實驗結果，以證明程式的可靠性，建立起簡單的拉福波理論基礎。

　　Love wave with pure shear-horizontal(SH) waveguide mode, in the presence of a guiding layer, is a wave that propagates with its energy concentrated in the guiding layer. Therefore, the propagation characteristics of the acoustic wave depends not only on the transmission media but the boundary condition of elastic surface and guiding layer. By detecting the variations of phase velocity and propagation attenuation constant, a Love wave sensor can be realized. And further, we can obtain the acousto-electric parameters of the unknown liquid by analyzing the relationship between these parameters and Love wave propagation characteristics.
　　In this dissertation, the propagation characteristics of Love wave in the piezoelectric single crystal substrates with different guiding layer and various propagation directions such as Quartz, LiNbO3 and LiTaO3 are completely discussed. First of all, wave propagation theory and numerical analysis techniques are applied to obtain the phase velocity, electromechanical coupling factor and attenuation constant. Then, the changes of wave propagation characteristics due to relative conductivity, and viscosity of the liquid loaded on the Love wave sensor are also discussed.
　　Finally ,we compared our simulation results with the experimental results and successfully established a simple simulation system of Love wave sensor.

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