A method which visualizes the distribution of a local electric field formed near a sample 2 is disclosed. A primary electron beam 1 which passes through the local electric field formed near the sample 2 is deflected by the local electric field, secondary electrons which are generated and emitted from a detection element provided downstream of an orbit of the deflected primary electron beam 1 are detected by a secondary electron detector 6, and an image formed based on the detected signal and a scanning electron beam image obtained by scanning the sample 2 are synthesized thus visualizing the distribution of the local electric field in multiple tones. Due to such an operation, it is possible to provide a method for visualizing the distribution of a local electric field in which the distribution of a local electric field can be obtained in multiple tone and in real time by performing image scanning one time using a usual electron beam scanning optical system.
