在绝对距离测量中, 由于大气扰动造成的测量路径上折射率分布不均匀对干涉测量有很大的影响, 针对这一问题, 本文提出了一种补偿大气折射率的多波长干涉测量绝对距离的方法。该方法基于小数重合法的基本原理, 在测量过程中不需要对大气参数进行实时监测, 而是通过 A系数所给出的各波长折射率之间的关系解算距离。文中结合小数重合法的基本原理给出了理论推导与分析, 并采用 594.1 nm、611.9 nm、632.8 nm三种波长在计算机上进行了数值仿真实验, 得到了该算法的小数级次测量精度与非模糊距离 (UMR)的匹配关系。

In absolute distance measurement, interferometric methods are severely affected by the uneven distribution of refractive index of air along the optical path with turbulence. To solve this problem, a multi-wavelength interferometric method for absolute distance measurement is presented, which can compensate for the refractive index of air in real time. Instead of monitoring the real-time environmental parameters, this method based on the excess fractions method can obtain the geometric length by using the relationship between the refractive index of different wavelengths provided by the A coefficient. A theoretical analysis based on the excess fractions method is presented, and a numerical simulation with 594.1 nm, 611.9 nm and 632.8 nm wavelengths is conducted on computer. The result shows the relationship between the Unambiguous Measurement Range (UMR) and the required fringe fraction resolution under this wavelength combination.