It is possible to inspect a liquid crystal panel and find a kind of defect without skill in a short time by the present disclosure. A part is inspected by using an extracted reference part which is extracted by i) calculating a vector data starting from a characteristic point on a contour of a part which is judged to be defectless, ii) determining the contour of a reference part according to the vector data obtained in i), and iii) extracting a reference part on the contour in ii). The kind of a part is judged by classifying the distribution of the two-dimensional static value of a defective part according to the distribution map of the two-dimensional static value of the histogram of a defective part obtained by experience.