Discussions were made on non-paraxial light ray through single-spherical refraction and the spherical aberration of the refraction image of lens.

• 如何减少球差或消除球差是研究、制造摄像机镜头、放映机镜头等光学系统很重要且复杂的工作，通常是采用多个透镜组合的办法达到减少球差的目的。