PURPOSE: To enable a visual field searched at high speed by electromagnetic deflection to be automatically located right under the optical axis by only pushing a key by providing a means of storing the position relative to the optical axis of a visual field moved by electromagnetic deflection, and a means of moving a sample stage.

CONSTITUTION: When an ON/OFF key 24a is pushed, an electron ray 3 scans an area (A) located right under an optical axis (C), and an image of the area (A) is displayed on a CRT13. When a Run key 24b is pushed, the visual field moves over areas (N1), (N2)... and (N8) in that order at given time intervals. Then, when a HALT key 24c is pushed, the designated area is continuously displayed on the CRT13. Next, when the RUN key 24 is pushed again, the visual field moves around the area (A) anticlockwise. Then, when a SHIFT key 24d is pushed, a controlling part 10 moves a stage 7 until the visual field comes right under the optical axis (C) according to the position of the visual field relative to the optical axis (C), and makes the outputs of output circuits 21X and 21Y zero.