This chapter will set the stage for our discussion of imaging using diffraction contrast. Put simply, diffraction contrast arises because the intensity of the diffracted beams is different in different regions of the specimen. These variations may arise because of changing diffracting conditions or because of differences in specimen thickness. In our study of diffraction in the TEM, we will see spots—lots of them. Sometimes the “spots” will be small faint points and other times they will be large disks, which themselves contain “structure” and more information. Other patterns will contain lines which we will examine in Chapters 19 to 21.
KeywordsBragg Angle Bragg Reflection Diffract Beam Path Difference Spherical Aberration
Unable to display preview. Download preview PDF.
- Bragg, W.L. (1965) The Crystalline State, I (Ed. W.L. Bragg ), Cornell University Press, Ithaca, New York (first published in 1933 ).Google Scholar
- James, R.W. (1965) The Optical Principles of the Diffraction of X-rays, The Crystalline State, II (Ed. W.L. Bragg ), Cornell University Press, Ithaca, New York (first published in 1948 ).Google Scholar
- Schwartz, L.H., Cohen, J.B. (1977) Diffraction from Materials, Academic Press, New York.Google Scholar
- Hecht, E. (1987) Optics, Addison-Wesley, Reading, Massachusetts.Google Scholar
- Hirsch, P.B., Howie, A., Nicholson, R.B., Pashley, D.W., Whelan, M.J. (1977) Electron Microscopy of Thin Crystals, 2nd edition, Krieger, Huntington, New York.Google Scholar