波前编码成像系统将模拟编码方法与数字解码技术相结合解决景深延拓问题，可以用信息光学的方法进行分析，得到波前编码系统的景深延拓扩展率。但是这种方法使用的景深概念和几何光学的景深概念有所不同。从几何光学角度研究了信息光学导出的波前编码系统的景深延拓扩展率与几何光学景深延拓的关系。最后得出结论，在F数一定的情况下，随着探测器分辨率的提高，几何光学景深延拓扩展率与信息光学给出的波前编码光学系统的景深延拓扩展率趋于一致。

Wavefront coding imaging system combines simulated coding method and digital decoder technology, which can resolve the problem of depth of field extension. It can be analyzed by the method of information optics. And the extension ratio of the depth of field for wavefront coding imaging system is obtained. However, the concept of the depth of field using this method is different from the concept of the depth of field of geometic optics. From the perspective of geometric optics, the relationship between the export of extension ratio of the depth of field for wavefront coding imaging system and geometric optics depth of field extension is discussed.