To review minute defects that were buried in roughness scattered light with an observation device provided with a dark-field microscope, a scanning electron microscope (SEM), and a control unit, the present invention configures the dark-field microscope by installing a filter for blocking a portion of the scattered light, an imaging lens for focusing the scattered light that has passed through the filter, and a detector for dividing the image of the scattered light focused by the imaging lens into the polarization directions converted by a wavelength plate and detecting the resulting images, and the control has a calculation unit for determining the position of a defect candidate detected by another inspection device using the plurality of images separated into polarization directions and detected by the detector.