Phase-shifting electron holography by beam tilting

A phase-shifting method to directly measure the amplitude and phase distribution of specimen in an electron holographic microscope without the introduction of large number of carrier fringes is proposed. The initial phase of electron holograms is shifted by tilting the incident electron beam with a digital voltage/current supply. Several holograms of a specimen with properly different phase shifts are recorded digitally and used to calculate the amplitude and phase distributions of the specimen. Experimental result of observing the phase distribution of a cubic MgO crystal is shown.