为了在薄膜形成期间跟踪生长表面应力水平的演变, 更加深入地探究薄膜应力的产生机理, 基于光束偏转法, 搭建了利用双光束照射在镀膜基底表面的实时测量光学薄膜应力的装置。装置软件系统从线阵CCD中提取双光斑位移的变化, 经过多次测量验证了算法的精确度, 使装置的精确度达到2.2%, 可以满足光学薄膜应力测量的要求。使用此装置跟踪SiO2薄膜镀制过程, 得到了应力变化曲线。结果表明, 双光束实时测量薄膜应力装置具有抗干扰能力强、精度高等特点, 可以为光学薄膜镀制过程中提供有效可行的原位应力测量手段。

In order to know the stress development in the film during growth and to study the origin and mechanism of the stress much deeply, an instrument based on light beam deflection for in-situ stress measurement in optical films by using two light beams is presented. An improved system is used to get the variation of the distance between the two beams. It is proved that the precision of the instrument is 2.2% after several times of measurement. This precision can satisfy the stress measurement of the thin film. The stress curve of SiO2 during growth is presented. As a result, the instrument represents an easy, stable, and high precision technique. It supplies an effective method for measuring the intrinsic stress.