METHOD AND DEVICE FOR INSPECTING UNEVENNESS IN CYCLIC PATTERN

摘要

PROBLEM TO BE SOLVED: To accurately and quickly inspect a cyclic pattern in an image for inspection obtained by imaging a subject to be inspected, and containing large amount of electric noise. SOLUTION: An image data (C) of extracted noise regions is obtained by extracting noise areas (noise caused by dust and electric noise) from inspection subject image data (A), (B) obtained by imaging an subject to be inspected. Areas for individual noise regions are measured in (D). Electric noise is identified assuming that noises have a measured area more than one pixel in (E). The inspection subject image data (A) corresponding to remaining noise regions (noise caused by dust) obtained by removing the identified electrical noise are substituted by representative values of pixels around the remaining noise regions to create an image data with removed remaining noise regions. A defect in the inspection subject is extracted based on the image data with removed remaining noise regions.