距离测量仪器的全室内校准是计量界和测量界的一项国际难题，多年来悬而未决，尚有不少瓶颈问题没有突破，室内长基线的建立就是其中的核心问题之一。此问题的难点在于"如何在有限的室内空间建立一条稳定、可靠的基线来代替野外长基线"。纵观国内外文献，对该问题的研究限于零星、初步和假想，与实际应用的要求相差甚远。基于此，申请人提出利用角锥棱镜建立室内基线。本课题拟研究：(1）影响测距仪发射光在基线场往返传播时能量损失的因素及能量损失的计算方法；(2)建立1km室内基线所需要的棱镜数和棱镜尺寸的确定方法；（3）棱镜的室内摆放方案；（4）基线系统的不确定度计算模型；（5）基线系统的实施方法。 目的是提出一套建立室内长基线的方法，为测距仪的室内检定提供解决方案。

The laboratory calibration of Electronic Distance Meters (EDMs) is an unresolved problem for ages internationally. Many bottlenecks need to be broken through, and "how to establish a long baseline in laboratory" is one of them. The nadir of the problem is "to establish stable and reliable a long laboratory baseline for substituting for the corresponding field baseline". However, existing achievements in literatures can not meet current practical demands. Thus, a method using corner cube prisms to establish a laboratory baseline is put forward.This study will research on (1)the factors effecting energy loss in the whole system, and the methods for calculating the energy loss; (2) the approach to determining the number and size of the corner cube prisms used in the 1km-long laboratory baseline; (3) the scheme for arranging the corner cube prisms in laboratory; (4)the model for calculating the uncertainty degree of the baseline system; and (5) the implementation method of the proposed baseline system. The goal of the study is to propose an approach to establishing a long laboratory baseline for providing a solution to the calibration of EDMs in doors.