| 摘要 |
PURPOSE:To avoid malfunction due to noise and to designate accurate read position by applying confirmation processing through the check as to whether an edge has a prescribed width or not in the case of edge detection. CONSTITUTION:When a white line is detected, the line is shifted one by one line each in the subscanning direction and retrieved till a black line is detected repetitively. This is the processing to recognize the edge of a mark 24c. when a black line is detected, the line is detected by one by one line shift further in the subscanning direction so as to detect a black line of a prescribed width in order to warrant the edge of the mark 24c repetitively. After a prescribed width of black line is detected, the black line detected early is confirmed as a 1st edge of the mark. Then the processing to retrieve a 2nd (reverse) edge of the mark is implemented. A white line is shifted from the first detection line in the reverse direction to above one by one line each till a black line is detected repetitively. |
