ELECTRON HOLOGRAPHY WITH A SUPERCONDUCTING OBJECTIVE LENS

The design of a transmission electron microscope with a super conducti ng objective lens and a field-emission gun operating at 80-100 kV is d escribed. The microscope, equipped with an electrostatic biprism is de signed for the holographic analysis of objects at liquid helium temper atures, e.g. to make use of the cryoprotection of biological objects f rom radiation damage. Special care was taken to achieve a high electri cal and mechanical stability of the microscope. Fundamental phase reso lution limits are discussed as well as the construction and performanc e of the instrument.