基于斯托克斯参量的光弹性应力分布及成像方法研究

Study of Photoelastic Stress Distribution and Imaging Method Based on Stokes Parameters

提出了一种基于斯托克斯参量测量的实时光弹性应力测量及其成像的新方法,对该方法的原理及参量测量方法进行了深入研究。根据分振幅斯托克斯参量测量原理设计一个实验系统,利用Equator-Poles(E-P)法定标系统,采用4个性能一致的光电探测器实现光束斯托克斯参量的快速实时测量。用实验系统测量单色平面偏振光通过光弹性样品后的斯托克斯参量,求得出射与入射偏振光的相位延迟量,再求得样品的应力值。运用该方法对有应力分布的平板玻璃和轴向受压有机玻璃进行测量并扫描成像,得到它们的应力分布图像。结果表明,该方法能够准确、快速和无损地测量光弹性样品任意位置的应力,实现对应力的实时测量。

A measuring and imaging method based on Stokes parameters with a division-of-amplitude polarimeter （DOAP） is presented. The theoretical calculation and parameters measurement are investigated. A DOAP system is designed and calibrated by Equator-Poles （E-P） method. Then, the Stokes parameters can be measured rapidly by use of four photoelectric detectors with the same performance. The Stokes parameters of monochromatic linearly polarized light that passed through the photoelastic sample are measured with the DOAP. Then the phase retardation between the emergent and incident polarized light is calculated and the stress value in the sample is obtained. A plate glass sample and an organic glass sample, which is subjected to axial compressive load, are scanned with this method separately, and their stress distribution are obtained. The experimental results show that, this method can measure the stress at any position of the photoelastic sample accurately, rapidly and nondestructively. It＇s a real time measuring method.