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Amplitude Contrast

  • David B. Williams
  • C. Barry Carter

Abstract

We’ve already mentioned in Chapters 2–4 that TEM image contrast arises because of the scattering of the incident beam by the specimen. The electron wave can change both its amplitude and its phase as it traverses the specimen and both types of change can give rise to image contrast. Thus a fundamental distinction we make in the TEM is between amplitude contrast and phase contrast. In most situations, both types of contrast actually contribute to an image, although we usually select conditions so that one will tend to dominate. In this chapter, we’ll discuss only amplitude contrast and we’ll see that there are two principal types, namely, mass-thickness contrast and diffraction contrast. This kind of contrast is observed in both TEM and STEM and in both BF and DF images. We’ll discuss the important differences between the images formed in each of these two modes of operation.

Keywords

Diffraction Contrast Stem Image Objective Aperture Collection Angle Amplitude Contrast 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

  1. References on diffraction contrast are included in Chapters 24–27.Google Scholar

General Imaging and Some History

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Early Haadf

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Copyright information

© Springer Science+Business Media, LLC 2009

Authors and Affiliations

  1. 1.The University of Alabama in HuntsvilleHuntsvilleUSA
  2. 2.University of ConnecticutStorrsUSA

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