% IMPORTANT: The following is UTF-8 encoded. This means that in the presence
% of non-ASCII characters, it will not work with BibTeX 0.99 or older.
% Instead, you should use an up-to-date BibTeX implementation like “bibtex8” or
% “biber”.
@INPROCEEDINGS{Chang:827181,
author = {Chang, Shery and Jin, Lei and Barthel, Juri and
Dunin-Borkowski, Rafal and Dwyer, Christian},
title = {{L}ow dose electron holography using direct-electron
detection camera},
address = {Weinheim, Germany},
publisher = {Wiley-VCH Verlag GmbH $\&$ Co. KGaA},
reportid = {FZJ-2017-01379},
pages = {769 - 770},
year = {2016},
comment = {European Microscopy Congress 2016: Proceedings},
booktitle = {European Microscopy Congress 2016:
Proceedings},
abstract = {The advent of commercially-available direct detection
cameras (DDCs) for transmission electron microscopy (TEM)
offers the opportunity to reduce noise in images and
diffraction patterns as well as providing fast frame rates
for image recording. For sufficiently low dose rates, their
design can enable significant improvements in detective
quantum efficiency (DQE) and modulation transfer function
(MTF) when compared to conventional charge-coupled device
(CCD) cameras. Existing literature on DDCs is focused
predominantly on structural biological applications, where
they provide clear advantages under low dose conditions,
e.g., typically < 10 e−Å−2 . Whereas the
characteristics of DDCs at dose rates and spatial
resolutions that are applicable to biological materials are
already well established, in many other areas of TEM the
dose rate can exceed 1000 e−Å−2, while the spatial
resolution can vary from nanometers to better than 1 Å. In
these contexts, the benefit of DDCs is less clear.Here, we
examine this question in the context of high-resolution
phase contrast imaging and off-axis electron holography and
demonstrate that the improved MTF and DQE of a DDC result in
clear benefits over conventional CCD cameras. For electron
holography, we find a significant improvement in the
holographic interference fringe visibility and a reduction
in statistical error in the phase of the reconstructed
electron wavefunction. In addition, we show that at least
three-fold improvement in optimum phase resolution using the
counting mode provided by DDC with four time less dose rate
compared that of a conventional CCD camera (with a fringe
spacing of 83pm in this case). Further improvement in SNR
could be obtained by correlation and averaging over a series
of holograms. As a result of the low camera noise, the
correlation of individual hologram is robust even at low
dose rates, and the averaging leads to an improvement in SNR
that is close to the ideal root-N behavior (N being the
number of images).Using BiFeO3 on DyScO3 substrate as an
example, we demonstrate that both specimen and birpism
fringe drift can be successfully correlated over 100 frames
of hologram (total exposure of 20 sec at a dose rate of 10
e− per pixel per sec), as shown in Fig. 2. Our results
show that DDCs are highly beneficial for electron holography
(and similarly to high-resolution TEM ) at low dose rates,
thereby minimising potential specimen damage while
maintaining an adequate SNR for analysis.},
month = {Aug},
date = {2016-08-28},
organization = {16th European Microscopy Congress (EMC
2016), Lyon (France), 28 Aug 2016 - 2
Sep 2016},
cin = {PGI-5 / ER-C-1},
cid = {I:(DE-Juel1)PGI-5-20110106 / I:(DE-Juel1)ER-C-1-20170209},
pnm = {143 - Controlling Configuration-Based Phenomena (POF3-143)},
pid = {G:(DE-HGF)POF3-143},
typ = {PUB:(DE-HGF)8 / PUB:(DE-HGF)7},
doi = {10.1002/9783527808465.EMC2016.6971},
url = {https://juser.fz-juelich.de/record/827181},
}