In conventional electron microscopes, orthogonality has been defined for each electron microscope individually in such a manner that a lattice sample is observed, and correction is applied to a control circuit so that the sample is observed as being orthogonal on a screen. Further, the correction has been determined by visual observation on a screen, and manually performed by a human operator. However, in this method, due to manufacturing variation of a lattice sample, the orthogonality may vary between devices. Further, there has been a problem in that the accuracy of correction varies by manually performing the correction. In order to solve the above problems, a particulate sample is used instead of a lattice sample for defining orthogonality, and adjustment is performed so that an image that should be a circle is observed as a circle, thereby making it possible to define the orthogonality.