论文部分内容阅读
针对相移算法中以双光束干涉为基础的余弦依赖算法的算法误差,以菲佐干涉仪精密测长为应用背景进行了研究。利用干涉光学的基本原理导出了在多束光干涉(经光学面多次反射、透射)的情况下干涉光强随相位分布的精确公式;通过数值分析得出了在给定参量条件下忽略次级反射光所引入的光强误差达到14.4%;对余弦依赖算法所引起的光强误差分别就四步算法、五步算法得出了不同的依赖关系:由于四步算法比五步算法对光强误差更为敏感,因而五步算法具有更高的准确度;对于两个反射面均具有较高反射率的情况,必须考虑算法误差;当测长准确度要求不太高时,在两个或至少其中一个反射面反射率较低的情况下可以忽略算法误差的影响。
Aiming at the algorithm error of cosine-dependent algorithm based on double-beam interference in phase-shift algorithm, the precise measuring length of Fizeo interferometer is used as the application background. Using the basic principle of interference optics, the exact formula of the interference light intensity with the phase distribution under multi-beam interference (multiple reflection and transmission through the optical surface) is deduced. By numerical analysis, The error of light intensity introduced by the reflected light reaches 14.4%. The error of light intensity caused by the cosine-dependent algorithm leads to different dependences on the four-step algorithm and the five-step algorithm respectively. Since the four-step algorithm is more efficient than the five- Strong error is more sensitive, so the five-step algorithm has higher accuracy; for the two reflectors have high reflectivity, the algorithm must be considered error; when the length measurement accuracy is not too high, in two Or at least one of the reflecting surfaces has a low reflectivity, the influence of the algorithm error can be neglected.