基于干涉成像原理，提出了一种结构简单的轴向可调式共光路干涉成像系统的设计。该设计充分利用光路可逆性和分光棱镜的反射、折射特性，先通过棱镜将入射光分为两束平行光，一束照射到样品上被反射载物台反射作为物光，另一束则直接被反射作为参考光，然后利用上述棱镜使反射回的物光和参考光合束发生干涉。通过调整棱镜的分光层与光轴之间的夹角可分别实现不同类型的干涉。分别以傅里叶变换和三步相移范数法为例对实验获得的干涉条纹进行相位恢复，并通过对结果的分析评估了系统的性能，对设计用于生物细胞相位成像的可行性进行了论证。所设计的系统结构简单、操作方便、系统误差小，可为均质细胞的无损免标记形态检测提供一种简单易行的方法。

An axial adjustable common-path interferometric phase imaging system with simple structure is proposed based on the theory of interference imaging. In this design, making full use of the reversibility of the optical path and the reflection and refraction characteristics of the splitter prism, the incident beam is split into two parallel beams by a prism. One beam is incident on the sample and reflected by the reflecting stage as object light, and the other beam is directly reflected as reference light. The interferograms can be captured by combining object beam with reference beam through the same beam splitter. The interferometer can achieve different types of interference by adjusting the angle between the layer of the beam splitter prism and the optic axis. Taking Fourier transform and three steps phase shift norm method as examples, the phase of the interference fringe is recovered, and the performance of the system is evaluated by the analysis of the results. The feasibility of the proposed design for biological cells phase imaging is demonstrated. The system has the characteristics of simple structure, easy operation and low system error, which can provide an easy and simple method for label-free morphological detection of homogeneous cell.