摘要
以随机相位屏作为待校正畸变波前,采用有限元分析方法,利用应力分析模型得到变形镜(DM)校正过程中的应力载荷谱,并基于应力-寿命(S-N)曲线和Miner累积损伤理论建立了变形镜的疲劳寿命预估模型,分析了波前校正过程中变形镜的疲劳损伤特性,并详细讨论了不同驱动方式及不同结构参数对变形镜使用寿命的影响。研究结果表明:在波前校正过程中,变形镜基底后表面损伤的程度大于前表面,基底与极头连接部位最易损坏。当待校正畸变波前形态一定时,波前峰谷(PV)值越大,变形镜的疲劳寿命越短;而当波前PV值一定时,畸变波前中的高频成分越多,变形镜产生的应力集中现象越明显,其疲劳寿命也随之缩短。此外,结构参数也会对变形镜的疲劳寿命造成影响,随着基底厚度的增加、极头长度的缩短,以及极头直径的增加,变形镜的疲劳寿命逐渐缩短。其中,极头直径变化所带来的影响最为明显。
A distorted wavefront to be corrected is built up based on the random phase screen. Then, the stress load spectrum of deformable mirror （DM） in the correction process is obtained by the stress analysis model with finite element analysis method. The fatigue life prediction model is proposed based on stress-cycle （S-N） curve and Miner cumulative damage theory. On this basis, the fatigue damage characteristics of DM for wavefront correction process are analyzed, and the influence of the different driving ways and different structural parameters on the lifetime of DM is discussed in detail. The results indicate that, in the wavefront correcting process, the fatigue damage of rear surface of DM substrate is more serious than that of front surface, and the joints between substrate and poles are most likely to be damaged. For a given shape of the distorted wavefront to be corrected, the fatigue life of DM decreases gradually with the increasing of the peak valley （PV） value of the wavefront. On the other hand, when the PV value of the wavefront is determined, the fatigue life also decreases due to more obviously concentrated stress caused by the increasing high frequency components in the distorted wavefront. Furthermore, the fatigue life can be affected by the structural parameters of DM as well. The life of DM decreases gradually with the increasing of the thickness of substrate, the decreasing of the length of poles and the increasing of the diameter of poles, among which the effects caused by the variation of the diameter of poles are more significant.
作者
陈丽霞
胡小川
张彬
孙年春
Chen Lixia Hu Xiaochuan Zhang Bin Sun Nianchun(College of Electronics and Information Engineering, Sichuan University, Chengdu, Sichuan 610065, China)
出处
《中国激光》
EI
CAS
CSCD
北大核心
2016年第11期179-187,共9页
Chinese Journal of Lasers
基金
中国科学院自适应光学重点实验室基金项目(LAOF201303)
苏州大学省级重点实验室开放课题(KJS1404)
科技部创新人才推进计划重点领域创新团队(2014RA4051)
关键词
几何光学
自适应光学
变形镜
疲劳
寿命预估
geometric optics
adaptive optics
deformable mirror
fatigue
life prediction
