脉冲激光输出模式对介质薄膜损伤的影响  

Effect of pulse laser mode on damage of dielectric thin film

作　　者：曹华梁[1] 程祖海[1] 叶克飞[1] 余亮英[1] 陈佳元[1] 

机构地区：[1]华中科技大学武汉光电国家实验室,湖北武汉430074

出　　处：《推进技术》2007年第5期558-560,共3页Journal of Propulsion Technology

基　　金：国家"九七三"项目(61328)

摘　　要：采用单横模(TEM01)和多模横向激励高气压(TEA)脉冲二氧化碳激光器和不同焦距的透镜对10.6μm的增透膜进行了破坏实验,对破坏样品进行了显微分析,研究了不同激光模式和不同焦距透镜对薄膜破坏的影响。实验结果表明,在短焦距透镜聚焦时,相同能量密度的单横模激光脉冲焦距前比焦距后更容易造成薄膜的损伤,破坏阈值相差5 J/cm2;使用长焦距透镜聚焦时,在单模激光脉冲和多模激光脉冲幅照下薄膜的损伤阈值基本相同,但比使用短焦距单模激光测量到的损伤阈值高。Laser induced damage in 10.6 μm reflection reducing coating was observed using single mode （ TEM01 ） and muhi-mode transversely excited atmospheric （TEA） carbon dioxide laser and different focal length optical lens. Damage sampies were analyzed by microscope. Effect of laser mode and focal length on damage of dielectric thin film was studied. The resuits show that single mode laser radiation of same energy density is easier to induce damage for sample in the front of focal spot of short-focus lens than that behind focal spot of short-focus lens. The deviation of damage threshold was 5J/cm^2. When using long-focus lens, the measured damage threshold of film is similar with single mode laser radiation or multimode laser radiation, but it is higher than that with single mode laser radiation when using short-focus lens.

关 键 词：激光损伤^+ 介质薄膜 破坏阈值 激光模式 

分 类 号：TN249[电子电信—物理电子学] V439[航空宇航科学与技术—航空宇航推进理论与工程]