Electron holography is holography with electron waves. Dennis Gabor invented holography in 1948 when he tried to improve resolution in electron microscope. The first attempts to perform holography with electron waves were made by Haine and Muley in 1952; they demonstrated recorded with 60keV electrons holograms of zinc oxide crystals and their reconstructions at about 1 nm resolution. In 1955 G. Möllenstedt and H. Düker invented biprism for electrons and recording of electron holograms in off-axis scheme became possible. Cowley has described 20 configurations for electron holography. Usually, high spatial and temporal coherence (i.e. energy spread) of electron beam are required to perform holographic measurements.
Read more about Electron Holography: High-energy Electron Holography in Off-axis Scheme, Electron Holography in In-line Scheme, Electromagnetic Fields, Applications