抄録
By use of high resolution electron microscopy the arrangements of heavy atoms within the unit cells have been visualized. It has increasingly become a powerful means, in particular, for studying crystal defects occurring at unit cell level. Feasibility of an intuitive interpretation of the lattice images, when the crystals are less than 100A thick, has been verified theoretically by n-beam dynamical treatment for electron diffraction and by taking into account of various electron optical parameters. Such calculations of the image contrast of crystals will provide more details of defect stru-tures derived from lattice images. An application of this new technique to the study of crystal defects in various non-stoichiometric niobium oxides is described.
