基于石英晶体天平和微纳光纤的有机污染物在线监测

Online Detection of Airborne Molecular Contamination with Optical Microfiber and Quartz Crystal Microbalance

为了监测高功率激光驱动器中有机污染物的挥发特性以及其在光学元件表面的沉积特性,研究了基于石英晶体微量天平和微纳光纤传感器的真空腔体内有机物在线监测技术.首先测试了不同分子态污染物浓度时石英晶体天平的响应性能,然后采用视角因子等分法对微纳光纤传感器和石英晶体天平进行对比实验,模拟有机污染物在光学表面沉积的特性.实验结果表明,石英晶体天平和微纳光纤测试有机物在光学表面沉积时响应一致,均可用于高功率激光驱动器有机污染物的在线监测;当污染物面密度大于0.5×10-5g/cm2时,微纳光纤传感器有较高精度和响应速度;有机污染物浓度越高,其更容易吸附沉积在光学元件表面.

In order to monitor the volatilization and deposition of organic contaminants on optics surfaces in high power laser facility,online detection of airborne molecular contaminant was investigated based on quartz crystal microbalance and optical microfiber.First,the response performance of quartz crystal microbalance for different densities of airborne molecular contamination was tested.Then the comparison of quartz crystal microbalance and optical microfiber in detecting the surface mass density of airborne molecular contamination was implemented with the view factor method.The characteristics of airborne molecular contamination deposited on optical surface were also studied.The experiment results show that quartz crystal microbalance and optical microfiber have the similar response performance,and thus they can be applied in online airborne molecular contamination detection.When the surface mass density of airborne molecular contamination is larger than 0.5×10-5g/cm2,optical microfiber is preferred due to the higher precision and larger response speed.The more the density of airborne molecular contamination is,the more it deposits on the optics.