| 摘要 |
<P>PROBLEM TO BE SOLVED: To achieve high sensitivity in detection while suppressing generation of a pseud defect by correcting threshold values when distribution of a gray level difference differs from the ordinary distribution in an image defect inspection method and a device in which the gray level difference of corresponding parts for two images is detected, the threshold value is automatically set up based on this distribution, these threshold values are compared with the gray level difference, and the defect is judged when the gray level difference is larger than the threshold values. <P>SOLUTION: Cumulative frequency of the gray level difference for the corresponding parts for the two images is calculated (S103), in the assumed designated distribution, the cumulative frequency is converted so that the cumulative frequency becomes a linear relationship to the gray level difference and the converted frequency is calculated (S104), an approximate straight line is calculated in each area where the gray level difference is positive and negative (S105), when the difference in tilt for each of the approximate straight lines is larger than a designated value (S106), the approximate straight line with the smaller tilt is corrected so that the tilt increases (S107), the threshold is determined based on this approximate straight line in accordance with the designated calculation method from the value for the designated cumulative frequency. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
