Defects/Contamination Detection Measurement

Color changes within the measurement region are used to find defects such as scratches, contamination, and chipping.
After measurement region is drawn, a rectangle (defect detection region) is automatically formed in this region.While moving the defect detection region around, calculate average density for each area to determine the difference between the original area and the surrounding area. This difference is called the defect level. Calculate the defect level for all defect detection areas. If the maximum value exceeds the judgement value, it is judged that there are defects in the measurement region.
Illustration of defect detection size
Increasing "Defect size" allows for shortening of processing time, but this will reduce measurement accuracy.
Setting item
Description
Upper limit
Lower limit
Specify the upper and lower limits of defect detection size based on the size of scratch or contamination to be detected.
The larger the difference between upper and lower limits, the easier it is to detect scratches or contamination of various sizes.
For both upper and lower limits, higher values for defect detection size limits leads to weaker detection sensitivity and shorter processing time.
Illustration of defect detection size