title: Development and implementation of electrostatic Zach phase plates for phase contrast transmission electron microscopy
creator: Frindt, Nicole Ursula Hannelore
subject: ddc-500
subject: 500 Natural sciences and mathematics
subject: ddc-530
subject: 530 Physics
subject: ddc-570
subject: 570 Life sciences
description: Transmission electron microscopy (TEM) plays an important role in structure determination of biologi- cal or material science samples. Resolutions up to the sub- ̊Angstrøm range are attainable. Weak phase objects do not reach this resolution due to their low signal-to-noise ratio. As the structure information of weak phase objects is mainly contained in their phase contrast, the conventional method for contrast enhancement is image acquisition at high defocus. This leads to a lower attainable resolution and con- trast inversion for different spatial frequencies, due to the sinusoidal phase contrast transfer function. As a consequence of these drawbacks, the development of physical phase plates for in-focus phase con- trast enhancement in TEM is of widest interest. In this thesis the development and application of the electrostatic Zach phase plate (ZPP) is presented. The impact of ZPP positioning on single sideband image artefacts is investigated. The applicability of the ZPP for inducing invertible and tunable phase contrast is demonstrated for the first time experimentally on frozen-hydrated biological samples. ZPP contamination, resulting charging artefacts and solution for these problems are presented. Furthermore the application of the ZPP with conventional electron optics and with a microscope containing a diffrac- tion magnification unit and an aberration corrector is compared. From this new insights into the design and use of an obstruction free anamorphic phase plate (APP) can be gained.
date: 2013
type: Dissertation
type: info:eu-repo/semantics/doctoralThesis
type: NonPeerReviewed
format: application/pdf
identifier: https://archiv.ub.uni-heidelberg.de/volltextserverhttps://archiv.ub.uni-heidelberg.de/volltextserver/14570/1/Dissertation_NicoleFrindt.pdf
identifier: DOI:10.11588/heidok.00014570
identifier: urn:nbn:de:bsz:16-heidok-145700
identifier:   Frindt, Nicole Ursula Hannelore  (2013) Development and implementation of electrostatic Zach phase plates for phase contrast transmission electron microscopy.  [Dissertation]     
relation: https://archiv.ub.uni-heidelberg.de/volltextserver/14570/
rights: info:eu-repo/semantics/openAccess
rights: http://archiv.ub.uni-heidelberg.de/volltextserver/help/license_urhg.html
language: eng