PURPOSE: To execute a satisfactory inspection up to th outside peripheral part of a pattern and to eliminate the influence of an image of a sample and a TV camera itself by executing an inspection, based on image pickup data so that a movement of the outside peripheral part of a periodic pattern part does not appear on an image.

CONSTITUTION: A mask 3 is provided on the reverse side (illuminating part 4 side) of a body to be inspected 2, so that a movement of an edge of a periodic pattern does not enter into an opening of the mask 3, at the time of executing an image pickup by illuminating by the illuminating part 4. That is, in case of executing an image pickup before the movement, the upper end of the pattern is allowed to coincide with the opening of the mask 3, and subsequently, the pattern is moved to the upper part and its lower end is allowed to coincide with the opening of the mask, and the image pickup is executed in its two positions. In such a way, a satisfactory inspection is executed to the vicinity of the outside periphery from a difference of both screens. Also, by forming the illuminating part 4 to a rough surface, the influence of an image of a sample and a TV camera itself is eliminated.