摘要
对光学元件表面划痕进行了细致的观察,并将它们分为单划痕、双划痕和多划痕三类,采用时域有限差分方法,以加工过程中常见的直径为二分之一波长的半圆形划痕为基本研究对象,数值模拟了位于光学元件前后表面的多条划痕附近的空间光强分布,总结了在不同划痕条数下光强最大值随着划痕间距变化的曲线图。结果表明:位于光学元件后表面的划痕比位于前表面时更加容易引起光学损伤;在多条划痕情况下,空间光强最大值随着划痕间距的增大呈周期性变化,并随着划痕间距的不断增大而趋于一稳定数值。
Surface damage of optical components is the main cause of lowering the laser-induced damage threshold. Surface scratches are observed exactly, and are divided into three kinds, namely, one scratch, two scratches and multi-scratches. By the method of Finite Difference Time Domain(FDTD), the intensity distribution around the surface scratches was numerically simulated on the basis of a common semicircle scratch with a half wavelength diameter. The graph of the maximal value of light intensity versus distance between scratches is got. It is concluded that optical damage is easily induced by scratches on the rear surface than those on the front surface. It also shows that in the case of multi-scratches, the maximum light intensity varies periodically with the increase of the distance between scratches and tends to be a constant at last.
出处
《强激光与粒子束》
EI
CAS
CSCD
北大核心
2006年第11期1832-1836,共5页
High Power Laser and Particle Beams
基金
国家自然科学基金委-中国工程物理研究院联合基金资助课题(10676023)
关键词
时域有限差分
亚表面缺陷
激光损伤阈值
光强分布
Finite difference time domain
Subsurface defect
Laser-induced damaged threshold
Intensity distribution