介质保护铝基高反膜的激光损伤特性研究

Research on Laser-Induced Damage Properties of High Reflective Index Medium Protected Al Film

激光系统中高反膜的抗激光诱导损伤能力限制激光器有效输出功率的提高.实验采用阻蒸法制备Al膜,采用轮廓仪测试薄膜厚度,利用lambda950测试光谱特性,在激光损伤测试仪上测试薄膜的激光损伤阈值.分析了沉积温度和厚度对薄膜光学特性和抗激光损伤能力的影响.研究结果表明：在不同沉积温度下,采用阻蒸法制备单层Al膜,当沉积温度为200℃时,在1 000-1 400nm波段的平均反射率达到95.59%,加介质保护膜后反射率提高到98%;随着膜层厚度的增加,其抗激光损伤阈值先降低再升高,沉积温度为200℃时,加介质保护膜的铝膜损伤阈值是单层铝膜的2倍;经零几率损伤激光能量辐照后,样片在1 000-1 400nm范围内的平均反射率降低了1%.

Laser induced damage ability of the high anti film in the laser system, which limits the effective output power of the laser. Preparation of experiments using resistance evaporated A1 film,With contour meter test the thickness of film,with lambda950 test the spectral characteristics of film,on laser damage the tester test the laser damage threshold of film. The influence of the deposition temperature and the thickness of the thin film optical properties and resistance to laser induced damage. The results show that： under different deposition temperature , using resistance steamed prepared a single-layer A1 film,when the deposition temperature of 200 ℃ the average reflectance 1 000 - 1 400 nm band reached 95.39 percent, after adding protective media to increase the reflectivity of the film to 98%; with increasing film thickness,its resistance to laser damage threshold decreased first , and then increased,the deposition temperature of 200 ℃ ,plus medium aluminum protective film damage threshold is twice than the single layer of aluminum; by zero chance after the iniury of laser energy radiation, samples average reflectance in the range of 1 000-1 400 nm reduced by 1%.