Intensity Distribution in Equal-Thickness Fringes in Electron Micrograph

Equal-thickness fringes in electron micrographs of aluminium single-crystal films have been energy-analysed. The intensity distribution in an ordinary E. M. image and that of electrons with negligible energy-loss have been measured. A phenomenological theory taking account of inelastic intra- and inter-band transitions and quasi-elastic inter-band transitions has been developed in good agreement with the experimental results. Reasonable values of the probabilities of these transitions are obtained.