| 摘要 |
PURPOSE:To widen the application range of the detection of a defect by detecting the defect by an image pickup element, obtaining a discrimination reference from the size of the defect and the length of the defect in a specific direction, and making a decision according to the kind of the discrimination reference. CONSTITUTION:When a defect of, for example, a seal member is detected, a defect 1 is thin and long, a defect 2 is circular, and a defect 3 is made in a finishing process. Then, the X-directional length aX of a defect and the size AD of the defect are measured and the length aX and size AD are combined to obtain the discrimination reference. Further, there is a specific relation between the length aX and size AD of the defect according to the kinds of the shapes 1, 2, and 3 of the defects and a decision reference is provided previously according to the kind of a defect. Then, the decision reference based upon the kind of the defect is applied for the measured discrimination reference and the defect is detected. At this time,the decision reference is made severe for the defect 1 having the high degree of criticalness. Thus, the discrimination reference is applied according to the kind of the defect, so it is decide correctly whether the surface is normal or not. |
