1. A method of judging a photo mask defect corrected portion, comprising: obtaining contour data of a photo mask whose defect has been corrected; obtaining information of a corrected region of the photo mask irradiated with a beam at the time of defect correction; synthesizing the contour data with information of the corrected region to obtain a transferred image onto a substrate, the contour data being provided with information of transmittance and phase and the information of the corrected region being provided with information of transmittance and phase change amount; and judging whether the corrected portion of the photo mask passes/fails from the image transferred onto the substrate.