Electron holography of individual DNA molecules

High-contrast holograms of unstained DNA molecules, deposited on a dedicated sample holder fabricated by silicon micromachining techniques, have been obtained in the low-energy electron point-source microscope. Recording at television rates allows dynamic processes to be observed. Numerical reconstruction of the holograms reveals the structure of the molecules depicted as the magnitude of the electron object wave front. © 1997 Optical Society of America.