eCommons

 

INVESTIGATION OF ADVANCED IMAGE RECONSTRUCTION ALGORITHMS FOR ELECTRON MICROSCOPY

Other Titles

Author(s)

Abstract

Aberration-corrected optics have made transmission electron microscopy a widespread and essential tool for 2D/3D material characterization at the atomic scale. With the rapid development of hardware and novel experimental techniques, there is an increasing demand for advanced algorithms to work with new experimental data or improve existing techniques. In this dissertation, we investigate a variety of image reconstruction algorithms for tomography and ptychography - two fast growing areas in electron microscopy. Using experimental and simulated data, we examine the limitations of advanced reconstruction algorithms and propose new methods to improve existing methods. Chapter 1 provides an overview of transmission electron microscopy and introduces some basic concepts in imaging science. Chapter 2 takes a more in-depth discussion of elastic scattering in STEM and how beam propagation can be described analytically and computationally. The next two chapters focus on electron tomography, a technique that reconstructs the 3D structure of the object. Chapter 3 describes the experimental setup and demonstrates an efficient Fourier-based reconstruction framework that works well with novel experimental techniques, including dual-axis tomography and through-focal tomography. In Chapter 4, we investigate the popular sparsity-exploiting reconstruction algorithms - exploring their practical limitations in the context of electron tomography. Chapter 5 introduces electron ptychography, a diffractive imaging technique that is enabled by the recent development of a high dynamic range detector. Here we demonstrate a full-field ptychographic reconstruction that doubles the spatial resolution of the traditional lens limitations. Finally, in Chapter 6 we further study the practical limitations of ptychography and propose new strategies for reconstructions.

Journal / Series

Volume & Issue

Description

Sponsorship

Date Issued

2018-05-30

Publisher

Keywords

Applied physics; Physics; Image Processing; Image reconstruction; Ptychography; Tomography; Electron Microscopy

Location

Effective Date

Expiration Date

Sector

Employer

Union

Union Local

NAICS

Number of Workers

Committee Chair

Elser, Veit

Committee Co-Chair

Committee Member

Bazarov, Ivan
Muller, David Anthony

Degree Discipline

Physics

Degree Name

Ph. D., Physics

Degree Level

Doctor of Philosophy

Related Version

Related DOI

Related To

Related Part

Based on Related Item

Has Other Format(s)

Part of Related Item

Related To

Related Publication(s)

Link(s) to Related Publication(s)

References

Link(s) to Reference(s)

Previously Published As

Government Document

ISBN

ISMN

ISSN

Other Identifiers

Rights

Rights URI

Types

dissertation or thesis

Accessibility Feature

Accessibility Hazard

Accessibility Summary

Link(s) to Catalog Record