ABSTRACT
As we have pointed out in the preceding chapters (4 and 5) we have separated electron sources from other types of electromagnetic radiation used to image materials because of their significance and contribution to the evaluation of the microstructure. Indeed, it is our belief that of all the techniques presented in this book, those described here have, over the past 50 years, provided the greatest contribution to the advancement of our understanding of microstructures and thereby the associated electrical, mechanical and overall physical properties of materials. As described in chapter 5, electrons like electromagnetic radiation can be considered either as waves or photons. However, the majority of techniques use monochromatic beams of electrons with a wavelength that is a function of the applied accelerating potential.
