| 摘要 |
PURPOSE:To peform common defect detection at little misdetection, by a method wherein the pattern of a first sheet is compared to the pattern of a second sheet or subsequent sheets in prescribed coordinate region about defect coordinate of the first patterns, and common defect is found. CONSTITUTION:Defect signal of pattern in a first sheet is detected by a detect discrimination circuit 15b. The defect signal is correlated to address signal from X-Y coordinate signal generating unit 14 and the coorelation signal is stored in RAM 107 of a defect recognition system 16. Defect signal of pattern in a second sheet is detected, and the defect signal is correlated to the address signal and the correlation signal is stored in the RAM 107. The defect data of pattern in the first sheet and the defect data of pattern in the second sheet both stored in the RAM 107 are compared by CPU 105 so as to determine whether common defect exists or not. The decision is effected regarding whether defect coordinate of pattern of the second sheet exists in prescribed coordinate region, for example, in 3X3 coordinate region about defect coordinate of pattern of the first sheet. In this constitution, misdetection is prevented. |
