激光频率分裂测波片的误差分析和实验评价

本文讨论了利用激光频率分裂技术测量波片位相延迟的主要误差因素,并对其中激光器初始位相延迟和波片非对正引入的系统误差进行补偿.误差分析表明:系统对于多级波片的测量不确定度约为1.7',对于零级波片为0.8',然后针对系统性能进行实验评价,包括:比较波片沿激光轴线对正和倾斜时对测量结果的显著影响,以及测量波片通光面内不同点的位相延迟和波片光轴与其表面的夹角.根据实测结果,系统测量重复性和复现性优于0.02°,不确定度优于2',即约λ/10~4.

Error Analysis and Experimental Testing of Measuring Wave Plate Based on Laser Frequency Splitting

The main error sources for measuring phase retardation of Wave Plate (WP) based on laser frequency splitting technology are analyzed. And the systematic errors, caused by the initial phase retardation of laser and misalignment of WP, are compensated. Error analysis shows that as to multi-order WP, the measuring uncertainty is 1.7' and as to zero-order WP, 0.8'. Its measurement performances are tested in experiments, including comparing the measurement results when WP is aligned or inclined to the laser axis, measuring the phase retardation at different points among the WP aperture; and evaluating the misalignment angle between WP optical axis and its surface. According to experimental results, this system demonstrates the repeatability and reproducibility better than 0.02°, and the uncertainty better than 2', viz. about λ/10~4.