光学元件残余应力无损检测技术概述

Residual stress measurement methods of optics

残余应力是光学元件的一个重要性能参数,对光学元件的制造和使用意义重大。光学元件残余应力的无损检测方法可粗略概括为两大类:一类是基于应变的测量方法,包括X射线衍射法、Stoney曲率法和显微拉曼光谱法,这些方法基于晶体和弹性力学分析方法,发展成熟、应用广泛;另一类是基于应力双折射效应的测量方法,包括数字光弹法、光弹调制器法和偏振光腔衰荡法,都是对残余应力导致的双折射相位差的测量,具有更直接的光学关联性、测量精度高的特点。本文归纳了光学元件残余应力测量的几种常见方法的测量原理、测量精度和应用场景,对比了它们的性能并分析了它们之间的关联性,以期建立起光学元件残余应力无损检测的宏观印象。

Residual stress is an important performance indicator of optics,which is of great significance to the fabrications and applications of optical components.Residual stress measurement methods of optics can be summed up into two categories:methods based on the strain measurement and on the stress induced birefringence measurement,respectively.The strain based methods,which are built upon crystal dynamics and elastic mechanics,including X-ray diffraction(XRD),Stoney curvature method,and micro-Raman spectroscopic method,are well developed and widely used.Methods based on the measurements of birefringence phase retardation induced by residual stress,including digital photoelasticity method,photoelasticitic modulator(PEM)method and polarization-dependent cavity ring-down method,show a higher precision.The principles,measurement precisions and application scenarios of these residual stress measurement methods are summarized in this overview.Comparisons between the performances of these methods are performed and correlations between them are analyzed in detail.