A universal electron diffraction microscope, as we call it, consists of three stage electron lens and two specimen chambers and functions both as an electron microscope and as an electron diffraction unit. This instrument can be used in the following seven ways:
(1) Electron microscope; range of magnification between 800 and 20 000 times can be covered continuously.
(2) Electron microdiffraction unit; electron diffraction pattern characteristic of any small area of a specimen under microscopic observation can be revealed by a switch.
(3) Dark‐field electron microscopic image.
(4) High‐resolution electron diffraction unit.
(5) Effective camera length of electron diffraction is variable from 0 to 250 cm.
(6) Shadow micrographs of the specimen used in (4) can be directly obtained.
(7) Shadow microdiffraction (probe diffraction); dark‐field microscopic image appears in each diffraction spot.
The specimen in the second chamber can be heated at any temperature up to about 800°C and on which two kinds of substances can be evaporated, and this evaporation gun can also be used for charge neutralization.