熔石英等光学材料激光损伤疲劳效应

Review on laser damage fatigue effects of fused silica andother optical material

以熔石英材料为主,以几种典型(铌酸铋晶体、三硼酸锂晶体和HfO_(2)/SiO_(2)多层膜)的光学材料为辅,介绍了其疲劳效应的主要表现;总结了激光波长、光斑直径、激光频率和材料位置对疲劳效应的影响;介绍了疲劳效应的两种模式:统计性的假疲劳和材料改性的真疲劳;介绍了疲劳效应的三种主要的机理解释:吸收缺陷模型、化学键断裂模型、色心模型;比较了疲劳实验中两种实验模式,并指出了两者的优缺点和适用研究对象。调研表明,对于不同类型的材料,使用不同的激光波长或其他差异条件,就有可能有不同的疲劳现象、源于不同的疲劳机理。

Under continuous laser irradiation,the damage threshold of fused silica and other optical materialswill continue to decrease,showing the“fatigue effect”,which seriously affects the life and stability of the repetitionfrequency optical system.This paper introduces the performance under fatigue effect of optical materials mainly fusedsilica materials,supplemented by several other typical optical materials(bismuth niobate crystal,lithium triboratecrystal and HfO_(2)/SiO_(2)multilayer film).The effects of laser wavelength,spot diameter,laser frequency and materialposition on fatigue effect are summarized.Two modes of fatigue effect are introduced:statistical false fatigue andmaterial modified true fatigue.Three main mechanisms of fatigue effect are introduced:absorption defect model,bond-breaking model and coloured center model.Two experimental modes in fatigue experiment are compared,andtheir advantages and disadvantages and applicable research objects are analyzed.Finally,the present research status ofthis field are summarized,and the future development trend and directions are prospected.