基板材料对光学薄膜近红外激光损伤阈值的影响

以电子束及电阻热蒸发镀制的TiO2、ZrO2、SiO2、MgF2、ZnS等单层膜及TiO2/SiO2多层膜为例,实验研究了熔石英(SiO2)、蓝宝石(Al2O3)以及氟化钙(CaF2)等不同基板材料对光学薄膜近红外激光损伤阈值的影响,结果发现,对单层膜及增透膜,基板材料对损伤阈值有较为显著的影响,其一般规律是阈值随基板热导率的提高而提高,而对高反膜,基板材料则无甚影响。文章结合体/面吸收研究以及损伤瞬态行为分析,用局部吸收导致热破坏这一机理,较好地解释了上述现象。

Damage threshold dependence of optical coatings on substrate materials

Damage threshold dependence on substrate materials was investigated of TiO₂,ZrO₂,SiO₂,MgF₂,ZnS single and TiO₂/SiO₂ multilayers.The results show that the damage threshold increases with increasing substrate thermal conductivity for single layers and AR coatings and remains the same for HR coatings.With the help of localized absorption measurement and in-situ damage process analysis,these phenomena were well correlated with local-absorption-initiated thermal damage mechanism.