表面热透镜薄膜吸收测量灵敏度提高方法

为提高表面热透镜薄膜吸收测量仪的灵敏度，在表面热透镜衍射理论基础上，通过数值模拟给出了探测激光腰斑半径、探测激光腰斑到样品表面距离、样品到探测光纤端面距离等仪器参数的优化方法．经优化调整后该仪器能达到优于0．1ppm量级的薄膜吸收率测量灵敏度．

In order to improve the sensitivity of surface thermal lens (STL) absorption measurement, numerical simulations are performed based on STL diffraction theory. The optimization method for choosing proper instrument parameters, including the size and position of probe laser waist and the position of detecting Fiber, is developed from the simulation. The sensitivity of the instrument reaches 0.1 ppm after the optimization.