| 摘要 |
PROBLEM TO BE SOLVED: To provide a technique that enables highly accurate positioning even when elements that make errors subject to spatial dispersion during imaging and elements that make errors stay at local positions coexist in a target area to be inspected.SOLUTION: An inspection device 1 divides a target image and a reference image into a plurality of blocks. Corresponding block areas of the target image and the reference image are compared on pixel-by-pixel basis while the block areas are being shifted to create a similarity map MB. As map points UR representing shift positions P (Δx, Δy) where similarity becomes high are contained in the similarity map, a minimum rectangle area Smin is set on the similarity map MB. Distribution index values Dx, Dy identified as widths of the minimum rectangle area Smin in X and Y directions, respectively, are compared with threshold values Dx0, Dy0, and determination as to whether the target block containing the minimum rectangle area Smin is a valid block is made. For calculation of fixed shift position for positioning, effective blocks only are used. |
