ELECTRON BEAM APPARATUS

An electron beam (4) to be irradiated onto a sample (10) is two-dimensionally scanned by a scanning coil (9), and secondary electrons generated from the sample (10) by the scanning are detected by a secondary electron detector (13). A deflection coil (15) for image shifting is used for electrically deflecting the primary electron beam to shift a field of view for image shift in an arbitrary direction by an arbitrary amount. By the image shift, the primary electron beam (4) to be irradiated onto the sample is energy dispersed to degrade the resolution. However, an ExB field producer (30) for dispersion control gives the primary electron beam energy dispersion in the opposite direction and having the equal magnitude. Therefore, the energy dispersion produced in the primary electron beam by the image shift is automatically corrected.