ADVANCES IN COHERENT ELECTRON-DIFFRACTION

Commercial transmission electron microscopes equipped with a field emission gun now produce a focused coherent probe smaller than the projected cell of many crystals. When the probe is slightly defocused, coherent fringe contrast is observed on the overlaps between discs in convergent beam patterns. Some recent results and future prospects are discussed, including coherent large angle patterns, the absence of coherent contrast in inelastic patterns and the phasing of zone axis patterns to recover the image wavefunction.