He Xiaoliang, Veetil Suhas P, Pan Xingchen, Sun Aihui, Liu Cheng, Zhu Jianqiang
Opt Express. 2018 Oct 1;26(20):25869-25879. doi: 10.1364/OE.26.025869.
Ptychography is a lensless phase imaging technique that obtains an image by scanning a specimen at several points with respect to a localized illumination beam. For larger specimens, it takes a longer time to complete scanning and hence higher stability is required in the setup which is often not guaranteed. An alternative technique is proposed here that reduces the sequential scanning time for such applications. A pinhole array is used to generate multiple tiny spatially separated beams to scan an object simultaneously at various points. The resulting diffraction patterns are recorded and processed in the Fresnel regime to obtain the images. Unlike other ptychographic methods using multiple beams, the proposed method does not require the use of a multimode ptychography algorithm or autocorrelation filtering of the diffraction patterns. The effectiveness of the method is studied through simulations and experiments. In contrast to conventional single-beam ptychography, the proposed method has the ability to achieve a larger field of view while leaving the number of scanned positions unchanged.
叠层成像术是一种无透镜相位成像技术，它通过相对于局部照明光束在多个点扫描样本以获取图像。对于较大的样本，完成扫描需要更长时间，因此设备需要更高的稳定性，而这往往难以保证。本文提出了一种替代技术，可减少此类应用中的顺序扫描时间。使用针孔阵列生成多个微小的空间分离光束，以便在不同点同时扫描物体。在菲涅耳区域记录并处理所得的衍射图案以获取图像。与其他使用多光束的叠层成像方法不同，该方法不需要使用多模叠层成像算法或对衍射图案进行自相关滤波。通过模拟和实验研究了该方法的有效性。与传统的单光束叠层成像术相比，该方法在扫描位置数量不变的情况下能够实现更大的视野。
