Theoretical interpretation on the electron microscopic image of crystal lattice and its moiré pattern

Abstract

It is well known that Menter (1) was the first who observed the image of lattice plane of crystal by electron microscope. He discussed the image by the kinematical theory of electron diffraction and Abbe’s theory. Before his observation, Uyeda (2) suggested that the image of crystal lattice will become equally spaced parallel stripes and Niehrs (3), by using the dynamical theory of electron diffraction, predicted that the lattice image of wedge-shaped crystal such as MgO smoke at exact Bragg angle will become parallel stripes with stepped structure. Recently Uyeda and Kamiya (4), by using the dynamical theory of electron diffraction, have discussed imaging of crystal lattice irradiated by slightly divergent electron beam. Cowley (5) interpreted the stepped structure appeared in the image of antigorite crystal by his theory. Present authors, by using the dynamical theory of electron diffraction, interpreted the images of crystal lattice with various crystal habits at exact and deviated Bragg condition and applied this interpretation to the image of two crystals superposed, i. e. moiré pattern of crystal lattice.