| 摘要 |
<p>With an attention paid to a specified area having characteristic surface conditions in a mark formed area or its surrounding area, an area computing apparatus (33) computes, while scanning a window with a width reflecting the specified area over the entire measuring area, characteristic quantities based on measured signals in the window. And, it specifies the position of measured signal area reflecting the specified area based on the positional distribution of the computed characteristic quantities to thereby extract a measured signal area reflecting a mark. A position computing apparatus (35) performs such operations as pattern matching in the extracted signal area, whereby a mark position is detected quickly and accurately.</p> |
