PATTERN CHECKING DEVICE AND METHOD

摘要

PROBLEM TO BE SOLVED: To provide the pattern checking device and method which can accurately check the completeness of a circular pattern. SOLUTION: A pattern segmentation part 24 extracts the image data on an area having a size large enough to include a through hole out of the pattern image data PD based on the center coordinate and the diameter which are calculated at a center coordinate/diameter calculation part 23. A circle recognition part 26 decomposes and extracts the boundary edge set between a pattern and the through hole via an edge extraction filter for the normalized image data in every prescribed direction component as the edge image data. Then plural edge image data are integrated by a hierarchical AND-OR filter while both gradation and thinning processing are carried out, and the output value indicating the degree of circle completeness is calculated. A threshold decision part 27 compares the output value of the part 26 with the prescribed threshold to decide the presence or absence of an opening angle error.