Ptychography是近些年快速发展起来的一种新型相位恢复技术,通过对待测样品以小于照明光直径的步长扫描后,利用迭代计算可以重建出照明光和样品复振幅分布,是一种理论分辨率为衍射极限的非透镜相位成像技术。虽然其提出初期受限于基本假定条件,但近些年随着相关研究的跟进,人们对Ptychography算法特性的理解逐渐深入,算法也日趋成熟,在可见光、X射线和电子束等领域已被广泛应用于相位成像、波前诊断和光学计量,因此针对影响重建过程和精度的关键因素,如模态多样化、扫描误差、光斑误差、距离误差、样品厚度不可忽略等进行了总结,并讨论了针对上述问题的关键技术进展。

Ptychography is a newly developed phase-retrieval technique based on lighting-probe scanning of a specimen in which the scanning step is smaller than the probe diameter. By using an iterative calculation, the complex-amplitude distributions of the probe and the specimen could be reconstructed simultaneously. Ptychography is a non-lens phase imaging technique with theoretically diffraction-limited resolution. Initially, the performance of Ptychography is limited by its basic assumptions. With the development of related researches in recent years, its characteristics have been gradually understood, and it has become increasingly mature as well. Nowadays, Ptychography has been applied to phase imaging, wavefront diagnostics, and optical metrology in the fields of visible, X-ray, and electrons. This paper discusses key factors that affect the reconstruction process and accuracy, including multiple modes, scanning errors, light-spot errors, distance errors, and non-negligible specimen thickness, and summarizes a development of key techniques to help overcome these factors.