Electron holograms for subångström point resolution

Abstract Using the Mollenstedt-type electron biprism [Mollenstedt and Duker, Z. Phys. 145 (1956) 377] in a Philips EM 420/ST with field emission gun we succeed in taking image holograms with a fringe spacing of 0.032 nm. This is the finest fringe spacing hitherto reported allowing the transfer of periods smaller than 0.1 nm by means of electron holography hence giving a point resolution below 0.1 nm after correction of aberration.