在Pound-Drever-Hall激光稳频方法中，有限元分析被广泛地用于优化光腔的加速度敏感度。在对腔体支撑进行建模时通常采用两种方式，即直接在腔体表面上取几块小区域进行约束或者使用刚性材料作为支撑。这里将有限元分析应用于更接近实际情况的采用软性材料支撑的腔体。采用软性材料支撑时，腔体受力后会出现较大的整体转动，干扰了腔长变化的计算。为此引入一种旋转坐标系的方法，该方法能够扣除掉腔体的整体转动效应。分析了一种软性材料支撑的长方体腔的加速度敏感度，并将之与直接在腔体表面上取几块小区域进行约束时的结果进行了比较，发现两者存在一定的差异。讨论了采用软性材料支撑时摩擦系数的设定和相应的支撑结构的建模方式。

Finite element analysis (FEA) is widely used to optimize the acceleration sensitivity of the optical cavities in Pound- Drever- Hall frequency locking method. In this process, mounting structure of the cavity is usually modeled by directly fixing small areas on the cavity or by using some rigid supports. The analysis is extended to more practical situations where the cavity is rest on some soft supporting materials. When subjected to forces, the cavity supported by soft materials exhibits a relatively large global rotation, interfering with the calculation of the length change. A method of coordinate transformation is introduced to deduct the effect caused by the global rotation. With this procedure added, the acceleration sensitivity of a rectangularbar cavity supported by soft materials is analyzed and the results are in some differences with the results obtained by directly fixing the cavity at the same locations. The choice of the the friction coefficient and the modeling of the supporting structure in the case of using a soft material to support the cavity is also discussed.