Etude théorique de la visibilité des plans atomiques en microscopie électronique

Taking into account actual capabilities of high resolution and very high voltage electron microscopes, conditions are specified which allow crystal lattices to be correctly imaged. The influence of parameters such as specimen thickness, defocusing distance, accelerating voltage, number of interfering beams is discussed. The inelastic scattering effect is also considered. The three-beam interference case in axial illumination is especially detailed. The method of calculation can easily be applied to other interesting operating modes, particularly in dark-field imaging which seems very promising.