有机污染与缺陷耦合损伤的抑制技术研究

Research on suppression technology for coupling damage of organic pollution and defect

在真空和空间环境下,光学薄膜的抗激光损伤能力会极大地降低,主要是由于真空环境中放气有机污染与薄膜内部缺陷的耦合效应导致薄膜光场增强。而保护膜技术是一项能够提高光学薄膜抗激光损伤能力的有效措施。基于时域有限差分算法,分析了保护层技术对有机污染液滴与缺陷耦合诱导薄膜光场增强的抑制作用。分析结果显示TiO_(2)薄膜光场的峰值随着保护层厚度增加而下降。保护层折射率为有机污染液滴和膜层折射率的中间值时,光场增强的抑制作用最大。实验结果也对理论分析进行了验证。该研究加深了对真空中光学薄膜抗激光诱导损伤降级机制的理解,对提高真空环境中光学薄膜的抗激光损伤能力有一定参考价值。

In vacuum and space environment,laser damage resistance of the optical film reduces greatly.This is mainly due to the coupling effect of organic pollution in the vacuum environment and the internal defect of the film,which results in the enhancement of the light field of film.The protective film technology is an effective measure to improve the ability of optical film to resist laser damage.Based on the finite-difference time-domain algorithm,the inhibition effect of the protective layer on the light field enhancement induced by the coupling of organic pollution droplet and defect was analyzed.The analysis result shows that the light field peak value of TiO_(2) film decreases with the increase of protective layer thickness.When the refractive index of the protective layer is the middle value of the organic pollution droplet refractive index and that of the film,the inhibition effect of light field enhancement is the greatest.The experimental results have verified the theoretical analysis.This study deepens the understanding of the mechanism of laser induced damage degradation of optical film in vacuum and has certain reference value for improving the laser damage resistance of optical film in vacuum environment.