DEFECT INSPECTION METHOD AND DEFECT INSPECTION DEVICE

摘要

PROBLEM TO BE SOLVED: To precisely extract pixels with continuity as a pixel group corresponding to one defect part and to improve the judgement precision of the presence or absence of a defect as a result by executing a processing which is hardly affected by noise. SOLUTION: A space area containing an inspection object is image-picked up (S1). An inspection area is set in an obtained density picture and spatial differentiation is executed (S3). The differential absolute values and the differential direction values of the pixels are calculated. A defect candidate pixel is executed based on the differential absolute values of the pixels (S4). Thus, nose is removed. Then, the defect candidate pixel is enlarged based on the continuity of the defect part and a defective candidate land where the continuity of the original defect part is reflected is obtained (S5-S10). The number of the pixels on the obtained defect candidate land is compared with the threshold. The presence or absence of the defect is judged (S11-S13).