A system includes an imaging optical system that forms an optical image of an observed object; a control apparatus that switches between a superresolution observation mode and a normal observation mode; and a rotatable disk located at a position conjugate to a front focal position of the imaging optical system and having a plurality of apertures. The imaging optical system changes a projection magnification of an intermediate image that is a point image of a portion of the observed object that is formed on the disk. The control apparatus sets, during the superresolution observation mode, the projection magnification in a manner such that the intermediate image becomes at least twice as large as the apertures and sets, during the normal observation mode, the projection magnification in a manner such that the projection magnification becomes lower than the projection magnification in the superresolution observation mode.