Abstract Quantification of fringe orders is important in visualizing full-field stress in digital photoelasticity. Various methods have been developed to improve the calculated accuracy of fringe orders, such as the phase shifting, carrier, and RGB methods. However, in these methods, fringe orders are calculated using the photoelastic patterns under a certain load but not the patterns in the whole time series; this impedes quantification of the fringe orders in dynamic photoelasticity. In this study, a polarized light camera was employed to simultaneously capture the photoelastic patterns of the dark and bright fields under circular polariscope. Based on the light intensity difference of these patterns in the entire loading process, a method of quantifying fringe orders is proposed. Full-field fringe orders in a disk fabricated by 3D printer and subjected to three compressive loads were calculated using this method. Its good accuracy, improved by removing the background light and choosing a suitable capture frame rate, was verified by comparing the fringe orders calculated by the traditional and proposed methods. Furthermore, the determination of the full-field fringe orders in complex structures indicated that the complexity of tested models had no influence on the calculated accuracy.

中文翻译：

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使用偏振光相机和连续加载量化光弹性条纹阶数

摘要 条纹阶数的量化对于数字光弹性中的全场应力可视化很重要。已经开发了各种方法来提高条纹阶次的计算精度，例如相移、载波和RGB方法。然而，这些方法中，条纹阶次是利用一定载荷下的光弹性图案而不是整个时间序列的图案来计算的；这阻碍了动态光弹性中条纹阶的量化。在这项研究中，使用偏光相机同时捕获圆偏光镜下暗场和亮场的光弹性图案。基于这些图案在整个加载过程中的光强差异，提出了一种量化条纹阶数的方法。使用该方法计算了由 3D 打印机制造并受到三个压缩载荷的磁盘中的全场条纹阶数。通过比较传统方法和提出的方法计算的条纹阶数，验证了通过去除背景光和选择合适的捕获帧率来提高其良好的准确性。此外，复杂结构中全场条纹阶数的确定表明，测试模型的复杂性对计算精度没有影响。