托马斯进动的发现对电子自旋概念的确立有重要意义. 然而，其物理图像及结论多是采用洛伦兹变换进行连续微分推导而出，过程较为繁杂，掌握难度也较大，在原子物理学教学过程中很难描述. 本文通过狭义相对论中长度在运动方向缩短的概念，从电子绕行原子实一周时，在原子实坐标系和电子随动坐标系中最终角度差的积分效应出发，非常简单的论证了 1 /2 的托马斯进动因子，其物理图像清晰，易于被学生理解和掌握.

The discovery of Thomas precession is of great significance to the establishment of the

concept of e- lectron spin. However，its physical images and conclusions are usually derived from

the differential process of con- tinuous Lorentz transformation. The method is complicated and

difficult to understand. In this article，based on the concept of shortening the length in the

direction of motion in the special theory of relativity，it is surprising to find that Thomas

precession angular velocity can be easily calculated by the integral effect of the

angle difference be- tween the nuclear reference system and the electron reference system

when the electron moves around the nuclear for a full circle.