ELECTRON GUN, AND ELECTRON MICROSCOPE

摘要

PROBLEM TO BE SOLVED: To provide an electron gun and an electron microscope, capable of improving observation efficiency (throughput) by making it easy to readjust the electron gun and an electron optical system, where the electron gun and the electron microscope are a field emission type electron gun and an electron microscope equipped with the electron gun, respectively, and a focal distance of the electron gun does not vary in the case of varying extraction voltage during observation.SOLUTION: A field emission type electron gun has a configuration including a magnetic field lens using a permanent magnet which is positioned at an adjustment potential other than an extraction voltage potential and to which a variable adjustment potential relative to an electron source is given.