ELECTRON HOLOGRAPHY AVAILABLE IN A NON-BIPRISM TRANSMISSION ELECTRON-MICROSCOPE

A method for taking electron holograms with a single crystal instead o f an electron biprism is described. The method is so simple that only a single crystal needs to be placed on the specimen grid in the specim en holder. Then, the crystal lattice fringes are focused on the record ing photographic film to form an off-axis Fresnel hologram. The proced ures for both hologram formation and reconstruction are described. Exp erimental results show that holograms can also be achieved with a conv entional transmission electron microscope having a low-coherence elect ron source.