光线的主平面和晶体的主截面

Principal Plane of Ray and principal Section of Crystal

本文提出了晶体光学教学由一个值得注意的问题:主平面与主截面是两个不同的物理概念,两者不能混为一谈,在教学中也不能有所偏重。

This paper puts forward a problem in crystal optics teaching which merits our attention: principal plane and principal section are two different physics concepts. The two concepts cannot be confused, nor be neglected in teaching.