Parameter retrieval of small particles in dark-field Fourier ptychography and a rectangle in real-space ptychography

Xukang Wei; H Paul Urbach; Peter van der Walle; Wim M J Coene

doi:10.1016/j.ultramic.2021.113335

Parameter retrieval of small particles in dark-field Fourier ptychography and a rectangle in real-space ptychography

Ultramicroscopy. 2021 Oct:229:113335. doi: 10.1016/j.ultramic.2021.113335. Epub 2021 Jun 24.

Authors

Xukang Wei¹, H Paul Urbach², Peter van der Walle³, Wim M J Coene⁴

Affiliations

¹ Optics Research Group, Delft University of Technology, Lorentzweg 1, Delft, 2628 CJ, The Netherlands. Electronic address: x.wei-2@tudelft.nl.
² Optics Research Group, Delft University of Technology, Lorentzweg 1, Delft, 2628 CJ, The Netherlands.
³ TNO Optics Department, Stieltjesweg 1, Delft, 2628 CK, The Netherlands.
⁴ Optics Research Group, Delft University of Technology, Lorentzweg 1, Delft, 2628 CJ, The Netherlands; ASML Netherlands B.V, De Run 6501, Veldhoven, 5504 DR, The Netherlands.

PMID: 34243020
DOI: 10.1016/j.ultramic.2021.113335

Abstract

We present a parameter retrieval method which incorporates prior knowledge about the object into ptychography. The proposed method is applied to two applications: (1) parameter retrieval of small particles from Fourier ptychographic dark field measurements; (2) parameter retrieval of a rectangular structure with real-space ptychography. The influence of Poisson noise is discussed in the second part of the paper. The Cramér Rao Lower Bound in both applications is computed and Monte Carlo analysis is used to verify the calculated lower bound. With the computation results we report the lower bound for various noise levels and analyze the correlation of particles in application 1. For application 2 the correlation of parameters of the rectangular structure is discussed.

Keywords: Cramér Rao Lower Bound; Parameterization; Poisson noise; Ptychograhy.