针对现有共光路径向剪切干涉仪所存在的干涉条纹对比度不可调、剪切相位差复原精度低或移相方式复杂、光学系统调整困难等缺点，提出一种对比度可调的共光路径向剪切移相干涉仪，利用偏振分束实现对比度连续可调，用偏振移相技术实现四步移相干涉。对波前重建精度的主要影响因素之一，即条纹对比度，进行深入的理论分析与实验验证；并对液晶空间光调制器(LC-SLM)生成的实际像差进行实验测试。结果表明，共光路径向剪切移相干涉仪可获得最高的条纹对比度，有关起偏角与条纹对比度之间关系的研究结果可为相关光学系统的设计与建立提供重要的理论依据。

A common-path radial shearing phase-shifting interferometer with adjustable fringe contrast is proposed against some disadvantages of conventional one, such as non-adjustable fringe contrast, low measurement accuracy of shearing phase difference recovery or complicated phase-shifting method, and difficulty of optical system adjustment. The contrast adjusted continuously is achieved using polarization beam splitters in this system, and the four-stepping phase-shifting interference is also carried out by the polarization phase-shifting technology. The fringe contrast which is one of the main influence factors about wavefront reconstruction accuracy is analyzed theoretically and verified experimentally. The actual aberration generated by liquid crystal spatial light modulator (LC-SLM) is measured experimentally. The results indicate that the common-path radial shearing phase-shifting interferometer can gain the highest fringe contrast. The research results of the relationship between the polarizing angle and fringe contrast can provide an important theoretical basis for the design and establishment of related optical systems.