Patent ID: 7466414

Claim:
A method of detecting a mark position as a position of a mark based on a position of a region corresponding to the mark within image data, the image data being obtained by a camera configured to receive an image of an object having the mark, and the image being formed by a scope, said method comprising: a first step of obtaining a first position of the region based on a first degree of correlation between a first template and the image data, the first template having a first feature point to obtain the first degree of correlation; a second step of obtaining a second position of the region based on a second degree of correlation between a second template and the image data, the second template having a second feature point, of which a position is different from that of the first feature point, to obtain the second degree of correlation; and a third step of detecting the mark position based on the first and second degrees of correlation, wherein the first feature point and the second feature point are different in polarity of the edge, and wherein each of the positions of the first and second feature points corresponds to a position of an edge of the mark.