自准法测焦实验中一个常见现象的说明

Narration on a Frequent Phenomenon in the Experiment of Auto-Collimating Method

本文就自准法测焦距实验中发现的不在我们测量范围之内的一个实像的成因做出了正确的解释。这样对做好实验防止误测有着重要的意义。

The article gives the proper expcianation about the cause of formation of a real image which is not within the measurement range in the experiment of auto-collimating method measuring the focus. It plays an significant role in preventing the experiment from measuring mistakenly.