Collection Of theses on high power laser and plasma physics, 2016, 14 (1): 0602009, Published Online: Mar. 22, 2017
Optimization of Morphology of Laser Induced Damage Mitigation Pit on Silica Optical Component
激光技术 激光损伤修复 时域有限差分法 瑞利索末菲衍射积分 laser technique laser induced damage mitigation finite-difference time-domain method Rayleigh-Sommerfeld diffraction integral
Abstract
Aiming at morphology of laser induced damage mitigation pit on the rear surface of 3ω silica optical component, the mitigated area and its downstream intensity distributions with different morphologies are simulated by finite-difference time-domain method (FDTD) and Rayleigh-Sommerfeld (R-S) diffraction integral method, respectively. The results show that when the angle between the tangent line of endpoints on the section contour of the pit and incident light is over 70°, the maximum intensity inside the mitigated optics is less than 1.66, and mitigation effect is better than that of other angles. The maximum downstream intensities of a pit in shape of parabolic surface, cone and truncated cone are all less than 1.46 with an angle of 70° and a width of 200 μm. But when the width of pit increases to 1 mm, for instance, the maximum downstream intensity is as high as 9.31 and area with high intensity covers a long range. Thus, taking the difficulty of laser machining technology into account, a conical pit with an angle larger than 70° is the first choice for the damage mitigation on the rear surface of silica optical component.
Zhou Li, Jiang Youen, Wei Hui, Fan Wei, Li Xuechun. Optimization of Morphology of Laser Induced Damage Mitigation Pit on Silica Optical Component[J]. Collection Of theses on high power laser and plasma physics, 2016, 14(1): 0602009.