用全息光栅精确定焦并检测象差

Focus determination and aberration testing by using holographic grating

焦距是光学系统最重要的特性参数之一。本文提出一种应用全息光栅精确测定焦距的方法。理论分析和实验结果表明：该方法原理简单，操作方便，精度较高。对全息光栅略加变化，即可用于测量光学系统的多种几何像差。

Focal length is one of the most important parameters in optical system,In this paper,a method for measuring focal length using holographic grating is given.This method is simple and precise.Aberrations of a lens can also be evaluated by using a special made grating or two orthogonal gratings with an angle of 45°。