Research On High Resolution Imaging Based On The Ptychographic Iterative Engine

Ptychographic Iterative Engine is a diffraction imaging technique which has been developed rapidly in recent years.Since no lens is needed in the optical setup,aberrations in traditional microscope modality can be greatly reduced,and the optical system can be simplified as well.There is a broad and bright prospect in the PIE application for many reasons.There are steady growing researches about PIE in the field of electron beam,X-ray and visible light.Other ptychographic imaging schemes,such as Single-shot PIE or Fourier Ptychographic Microscopy(FPM),are all based on the basic PIE algorithm.Therefore,the study on PIE is crucial.This paper will discuss PIE technique in the following aspects:Implementation of the basic PIE algorithm simulation;Test of validity of simulation program;Analysis of the experiment results by changing key parameters in order to provide the best reference parameters for the actual experiments;Discussion of the impact of parameter measurement error on retrieval fidelity,determine that some measurement deviations can be corrected by just increasing the number of iterations,while others require advanced correction processes;Reproduction of the ePIE algorithm,where distribution of the sample and illumination probe can be retrieved simultaneously.This paper presents the theory and compares retrieved images following different parameters.And the influence of different parameter values selected for the retrieval.Finally,the problem of periodic error in retrieved image is discussed and a relevant solution is given.The proposition of Ptychographic Illumination of Axial Acceleration Retrieval,PIXAR,algorithm;Implementation of simulations under the PIXAR scheme;Analysis of retrieved image results;Discussion of the reason of image degradation.Analysis of retrieved image quality using different illumination probes.Validation of the algorithm in the simulation that is closer to the reality,where the probe is the diffraction result of a Gaussian beam.Comparison of retrieved images using following scanning modes: two-dimensional PIE scanning,circular PIE scanning,and PIXAR scanning.The proposition of experiment setup of the PIXAR algorithm.The design of PIE experiment scheme,selection of experimental devices and implementation of the experiment.The design of automated data acquisition module.Analysis of retrieved images below both PIE and ePIE algorithms.In e PIE algorithm,different initial assumptions are used in this recovery process.Different results in e PIE algorithm are also discussed.The section line in the retrieval of 1951 USAF resolution chart gives a more visualized comparison of the recovery quality.Comparison of the recovered phase distribution of illumination probe and actual distribution.Analysis of experiment module that degrades the experiment results most and provides corresponding measures that could be adopted in further researches.