表面杂质和节瘤缺陷诱导薄膜元件热熔融损伤

Thermal melting damage of thin film components induced by surface impurities and nodule defects

在高功率激光系统中,光学薄膜元件表面杂质和体内节瘤缺陷是导致薄膜元件损伤的关键因素。通过建立强激光连续辐照下光学薄膜元件的热分析模型,分析在不同激光辐照时间和功率密度下,表面杂质和节瘤缺陷对光学薄膜元件损伤的影响及其规律。结果表明,在强激光连续辐照下,当表面杂质粒子尺寸处于一定范围内时,随着杂质粒子尺寸的增大,薄膜元件上的最高温度随之升高,且大而浅的节瘤缺陷种子对膜层的温升影响较大。随着激光功率密度的提高和激光辐照时间的增长,表面杂质造成薄膜元件热熔融损伤的粒子尺寸范围越大,节瘤缺陷造成薄膜元件热熔融损伤的种子深度和尺寸范围也越大。

In the high power laser system,surface impurities and nodule defects are the key factors causing laser-induced damage of thin film components.The influences and variations of surface impurities and nodule defects on the laser-induced damage of thin film components for different irradiation time and power density were analyzed by establishing the thermal analysis model of thin film components irradiated by continuous high power lasers.The results indicate that,when the surface impurities are irradiated by continuous high power lasers,and their size localizes within a certain range,the maximum temperature of the film components increases with the increasing of impurity size,and the large and shallow nodule defect seeds have a more obvious influence on the temperature rise of the film.With the increasing of the power density and the irradiation time,the range of the impurity size in which the surface impurities cause the thermal melting damage of the thin film components increases.Simultaneously,the range of the seed depth and size of the nodule defects causing the thermal melting damage of the thin film components is broaden.