The electron gun, charge part of the same gun and charge part chen beam device with the use of the electron gun and the charge part of the same gun

摘要

The electron gun, containing:a needle-like electron source (1), which as a field emission - electron source acts. an accelerating electrode (3) in order to accelerate the of the electron source (1) emitted electrons;a control electrode (2), which is located closer to the side of the electron source (1) than at the side of the acceleration electrode (3) and is disposed at a larger opening diameter than a diameter of opening of the acceleration electrode (3); anda control section (6) for controlling a to the control electrode (2) on the basis of a potential which is applied to the acceleration electrode (3) applied potential, characterized in that, under the condition that the diameter of opening of the control electrode (2) as the d is defined and a distance between the electron source (1) and the acceleration electrode (3) is defined as l, a ratio of d to l of d / l & 1 is provided, and the distance between the electron source (1) and the acceleration electrode (3) than 6 mm & l 20 mm is defined.