Electron microscopy
 
Streaking Artefacts in FFTs of TEM Images
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Vertical and horizontal streaking artefacts can be generated in FFTs of a TEM image due to the appearance of the sharp discontinuity or called mismatch between the intensities at the image edge. In some cases, an edge damping filter can be applied to the image before Fourier transformation (e.g. FFT) in order to remove the streaking artefacts.

For instance, Figure 1419 shows the FFT pattern from a HRTEM image. The spots reflect the lattice planes of the original HRTEM image. Note that in the FFT pattern, the long streaks that run normal to the edges of the mask are artifacts of the processing.

An example of typical FFT patterns

Figure 1419. (a) HRTEM image of Fe rich matrix viewed along <001>α displaying ordered areas (A) and disordered areas (B or C). (c) Fast Fourier transform of the whole HRTEM image showing superlattice reflections (100) and (010). Adapted from [1]

 

 

 

 

 

[1] P. Galimberti, S. Lay, A. Antoni-Zdziobek, S. Coindeau, b, M. Véron, F. Bley, M. De Boissieu, Precipitation and hardening behaviour of the Fe20Co18W alloy aged at 800 °C, 19 (4) (2011) 556–562.

 

 

 

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