Diffraction contrast imaging using virtual apertures

Autor(en)

Christoph Gammer, V. Burak Ozdol, Christian H. Liebscher, Andrew M. Minor

Abstrakt

Two methods on how to obtain the full diffraction information from a sample region and the associated reconstruction of images or diffraction patterns using virtual apertures are demonstrated. In a STEM-based approach, diffraction patterns are recorded for each beam position using a small probe convergence angle. Similarly, a tilt series of TEM dark-field images is acquired. The resulting datasets allow the reconstruction of either electron diffraction patterns, or bright-, dark- or annular dark-field images using virtual apertures. The experimental procedures of both methods are presented in the paper and are applied to a precipitation strengthened and creep deformed ferritic alloy with a complex microstructure. The reconstructed virtual images are compared with conventional TEM images. The major advantage is that arbitrarily shaped virtual apertures generated with image processing software can be designed without facing any physical limitations. In addition, any virtual detector that is specifically designed according to the underlying crystal structure can be created to optimize image contrast.

Organisation(en)

Physik Nanostrukturierter Materialien

Externe Organisation(en)

Lawrence Berkeley National Laboratory, University of California, Berkeley

Journal

Ultramicroscopy

Band

155

Seiten

1-10

Anzahl der Seiten

10

ISSN

0304-3991

DOI

https://doi.org/10.1016/j.ultramic.2015.03.015

Publikationsdatum

08-2015

Peer-reviewed

Ja

ÖFOS 2012

103018 Materialphysik

Schlagwörter

ASJC Scopus Sachgebiete

Electronic, Optical and Magnetic Materials, Instrumentation, Atomic and Molecular Physics, and Optics

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/227ddbba-e898-4203-89d5-17d2fc654d6c