Patent ID: 6571196
Filing Date: 2003-05-27
Classification: G01B

Abstract:
A method of inspecting or measuring size of an object, comprising the steps of:setting contour registration areas of at least two locations of a reference object; detecting and registering contour positions of said reference object at each of said contour registration areas; setting an inspection area or a measurement area for an inspection or measurement object; registering contour positions of said inspection or measurement object within said inspection or measurement area of said inspection or measurement object; obtaining respective values of correlation between said contour positions of said inspection or measurement object and said contour positions of said reference object; detecting a position relating to the highest one of said values of correlation at each of said contour positions of said inspection or measurement object; and obtaining the size of the object based on the registered contour positions of said inspection or measurement object, wherein said steps of detecting contour positions of said reference object and registering said contour positions of said inspection or measurement object include the step of calculating a position of an a-th pixel as n+(Vnâˆ’VsL)/(Vnâˆ’Vn+1), wherein VsL indicates a luminance level of the a-th pixel and is 50% of a maximum level, and Vn and Vn+1 indicate luminance levels of n-th and (n+1) pixels, respectively.