PURPOSE: To achieve a higher measuring accuracy, by varying the magnification of orthogonal two axes in a measuring view composed of electron beam scans over an object to be inspected at a display section.

CONSTITUTION: A sample 2 to be measured is placed on an XY table 1 and then, the table 1 is moved to hold a specified portion of the sample 2 within the irradiation range of electron beams 7 from an electron beam source 6. Then, the specified portion of the sample 2 is scanned by the electron beams 7 to compose a measuring view range. In this case, the magnitude of x and y in the longitudinal and laterial way of the measuring view are made unequal in sides as shown by x>y with an electron beam source control section 11 and the values thereof are held at a main control section 16. On the other hand, secondary electrons 8 released from the sample 2 with the scanning of the electron beams 7 are trapped with secondary electron detectors 9 and 10 and the number of the electrons trapped at the secondary electron detectors 9 and 10 are converted into electronical signals respectively with signal conversion section 12 and 13. Then, the signals are synthesized with a image processing section 14 into an image and an image equal in sides is outputted to a display section 15 from the measuring view unequal in sides based on the values of x and y held at the main control section 16.