高倍率显微物镜具有小视场短焦距的特点，但利用常规测量方法难以准确测定其焦距。采用了一种基于放大率法多次基准传递的方法对高倍率显微物镜的焦距进行准确测定。该方法的原理是采用放大倍率法测试一枚远场共轭设计的低倍率显微物镜，获得该物镜的焦距，然后以此低倍率物镜测试高倍率显微物镜。利用该测试方法对一枚标称焦距为4 mm Nikon金相物镜进行了测试，并分析了测试误差，测试精度为0.0266 mm，相对标准差为0.664%。发现用于基准传递的物镜的选择会影响最终的测试精度，从理论上分析了选取合适基准物镜的标准。

The high-magnification microscope objective lens (HMOL) have small field and short focal length. Measurement of this short focal length is difficult in a conventional way. The focal length of high-magnification microscope objective can be measured using multiple reference transfer based on magnification method. This method is that an infinity design of low-magnification microscope objective lens (LMOL) is measured, the focal length of the LMOL is obtained, and then using the LMOL instead of collimator to measure the focal length of HMOL. This method is used to measure a Nikon metallographic objective lens (nominal focal length is 4 mm) and the errors are analyzed, testing accuracy is 0.0266 mm, and relative standard deviation is 0.664%. This fact that the choice of the objective lens used for reference transfer will affect the accuracy has been noticed, and a standard for choosing the appropriate benchmark objective is proposed.