DETECTING METHOD OF ALIGNMENT MARK

摘要

PURPOSE: A method for detecting an alignment mark is provided to accurately check the central coordinate value of a mark by using pixel values that change continuously in images. CONSTITUTION: An alignment mark image is obtained. A test image (25) is extracted from the alignment mark image. A virtual test region (40) is set in the test image. At least two boundary lines are set as each test line (50). The pixel value of the image is confirmed on each test line.