摘要 |
A method of and an apparatus for detecting a pattern defect in such a manner that a difference between a pair of patterns is detected by two-dimensionally comparing a first binary signal obtained by scanning and imaging one of the patterns, with a second binary signal corresponding to the other pattern and obtained by scanning and imaging the other pattern or previously stored in storage means, is disclosed. The apparatus for detecting a pattern defect comprises means (23, 24) for delaying two binary signals corresponding to a pair of patterns by a predetermined amount, and means (22) for detecting a positioning error between the patterns, in a period when the binary signals are delayed by the predetermined amount, by comparing each of picture elements included in a predetermined area of a two-dimensional image corresponding to one of the patterns which has been two-dimensionally delayed, with a specified picture element included in an image corresponding to the other pattern which has been delayed, and by summing the result of comparison at each of the former picture elements. |