微型光热驱动机构的光热膨胀理论模型与实验研究

提出和发展了一种基于微尺度光热膨胀效应的微型光热驱动机构.建立了膨胀臂的微尺度光热传导与膨胀的物理模型，利用有限元分析和数学物理方法，推导出膨胀臂的一维温度分布表达式及光热膨胀量和偏转量的计算公式.利用准分子激光微加工系统设计制作了一个长度为1200?μm 的微型光热驱动样机，根据激光和样机的相关参数，计算得到光热膨胀量与激光功率之间的理论关系曲线.实验结果表明，微型光热驱动机构的光热偏转量（对应于膨胀量）与照射到膨胀臂上的激光功率近似成线性关系，实验曲线与理论模型及计算结果符合良好.在理论和实验研究基础上，作为光热微驱动的应用实例，设计并加工制作了一个双向微开关型光热驱动机构，并通过实验实现了双向微开关功能.关键词：光热膨胀臂微驱动机构光热传导模型激光

Theoretical modeling of microscopic photothermal expansion and experimental study of photothermal microactuators

A novel photo thermal microactuator based on microscopic photothermal expansion is developed. A theoretical model of photo thermal expansion for photo thermal microactuator is established. Using finite element analysis and numerical method, the expressions of the temperature distribution and the linear thermal expansion are deduced. A photo thermal microactuator of 1200?μm length is fabricated by using an excimer laser micromachining system. According to the parameters of the laser and the photo thermal microactuator, a theoretical relationship between the expansion and the laser power is calculated. The results indicate that the photo thermal microactuator deflection （corresponding to expansion） is approximately linear with the laser power irradiating the expansion arm, according with theoretical predictions quite well. As an application, a Bi switch like photo thermal microactuator is built and the successful photo thermal microactuation experiment shows the Bi switch function can be realized.
Keywords：photothermal expansionmicroactuatormodel of photothermal transmissionlaser