1. A scanning electron microscope system comprising: a scanning electron microscope including a sampling stage capable of mounting the specimen for observation and moving to change the observation position of the specimen; an image input device to obtain the signals measured by the scanning electron microscope as images; a storage device to store the images that were input; an arithmetic logic unit (ALU) to process the image and make various types of corrections; an input device to enter the conditions for making corrections; and an output device to output the corrected image, wherein the scanning electron microscope system measures a correction reference image in a shorter time than the observation image: and detects distortion in the observation image caused by drift of the sampling stage that occurred during specimen observation in line units on the applicable observation image by comparing the observation image with the correction reference image, and corrects the detected distortion in line units, and outputs an image with lower distortion.