| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a defect detection apparatus for obtaining indices of categories of types or degree of defects and complexity of shapes of the defects. <P>SOLUTION: The defect detection apparatus for optically detecting the defects on a surface of a product and judging the defects is provided with an image pre-processing means for extracting edges of an image signal or filtering the image signal and normalizing the image signal, a means for binarizing the image signal, a means for calculating a fractal dimension about the binary image and a means for determining the defect by using the fractal dimension as a characteristic quantity of the complexity of the shapes of the defects. The defect detection apparatus judges the defects by using a residual pixel number measurement means and the characteristic quantity of the complexity of the shapes of the defects. The image pre-processing means is a filtering processing means for scanning by using a Laplacian filter. The defect detection apparatus is provided with a means for measuring entropy of intensity of the image before binarization, or judges the defects by applying the maximum likelihood determination method to the determined characteristic quantity. <P>COPYRIGHT: (C)2004,JPO |
