利用朗伯定律重建了光学三角法测位移的原理公式。与用几何光学原理建立的公式进行了比较。利用新公式对影响光学三角法测位移精度的主要误差因素进行了深入的分析，给出了实验结果。并提出了减小和校正误差的方法。

In view of the Lambert′ theory, the authors have rebuilt the principle formula of optical triangulation method for displacement measurement. Comparison has been made between the new formula and the old formula built on geometric optics. Using the new formula, analysis of the principle factors which affect the displacement measurement precision of optical triangulation method has been carried out. The experemental results has been reported. The methods has been suggested for decreasing and coorecting the errors.