Calculations were made of the far-field shadow image below a thin crystal when a coherent electron source was placed at μm-distances above the specimen. It was noted that the presence of a planar fault produced a very strong oscillatory contrast. These predictions were reproduced experimentally by using a field-emission electron source in a microscope. By using this technique, it was possible to determine the displacement vectors at planar faults to within an accuracy of 1pm in the case of Bi2Sr2Cu2CaO8 which contained thin intercalated layers.

Picometer Accuracy in Measuring Lattice Displacements Across Planar Faults by Interferometry in Coherent Electron Diffraction. L.Wu, Y.Zhu, J.Tafto: Physical Review Letters, 2000, 85[24], 5126-9