PURPOSE: To facilitate selection of a desired visual field by taking a sample in and by displaying it as a TV image by an optical camera device, and by having its coordinates corresponded to the coordinates of a sample stage of an electron microscope having a readable stage.

CONSTITUTION: The intersection of X-axis and Y-axis is determined on a sample stage 4 on the lower part of a scanning electron microscope cylinder 1, and the point becomes an origin of coordinates. Specific points A, B, C are determined on the X and Y axes for a sample 3 on a sample holder 2 on the stage 4, and their coordinates are thus found. The sample 3 is displayed by a display device 6 of an optical camera device 5, and is stored in an image intake memory part 7. Cross coordinate axes are drawn on the device 6, and the stage 4 of the electron microscope corresponds with an image screen by giving coordinates of each point on X and Y axes for the specific points A, B, C. The coordinates of optional points on the device 6 are read and the stage 4 is moved, thereby observation is facilitated by means of the electron microscope image.