Device for visual control of position adjustment of cathode of electron gun of electron microscope e.g. scanning microscope, has glasses with diametrically arranged apertures formed corresponding to cathode in working position

摘要

The device has an annular base (1) on which an anode executed as glass with a central aperture is detachably set up. A position adjustment device adjusts position of cathode (4) with respect to annular base. The diametrically arranged apertures (9,10) are formed in the walls of glasses (7), such that positions of apertures correspond to the position of upper point of cathode in working position.