相位差（PD）波前探测器具有光路简单、共光路测量等优点，不仅适合点目标，而且适合扩展目标。随着算法和硬件水平的不断提高，相位差法已经成为波前探测技术的一个重要发展方向。对相位差波前探测器进行了研究，成功实现了对点目标和扩展目标的波前探测，给出了数值仿真结果。针对点目标，搭建实验光路，对静态的单阶Zernike像差和随机像差进行探测，分析了影响探测精度的主要因素。结果表明，相位差波前探测器可以准确地探测波前，在给定的实验条件下，相位差法对低阶像差探测的均方根误差小于λ/100，对随机像差的探测的均方根误差小于λ/50。

With the improvement of the algorithms and hardware, phase diversity wavefront sensing technology becomes an important developing direction of the wavefront sensing technology, which is attributed to many advantages such as simple configuration, common path detection and so on. Phase diversity wavefront sensor is simulated not only for point sources but also for extended sources. An experimental testbed is built based on point source to detect the static Zernike aberration. Numerical simulations and experimental results demonstrate that phase diversity wavefront sensing technology can retrieve the wavefront accurately. Under the given experimental condition, the root mean square of the residual aberration is about λ/100 for the low order aberrations and less than λ/50 for the random aberrations.