| 摘要 |
PURPOSE:To efficiently inspect the wiring patterns of a printed wiring board having the wiring patterns on its both surfaces or of a plurality of kinds of printed wiring boards CONSTITUTION:Two kinds of reference picture patterns which are to be compared with the wiring patterns on both main surfaces of a printed wiring board 2 are stored in advance in two semiconductor memories SM1 and SM2 from which the wiring patterns can be read out at high speeds. When the wiring patterns are inspected for defects, one appropriate reference pattern is selectively read out from the memories SM1 and SM2. During the defect inspection, the number of defects is counted and, when the number exceeds a prescribed reference value, the defect detection is stopped and the defect detection is restarted after reading out the other reference pattern from the memories. Therefore, the defect inspection can be performed efficiently even when the picture pattern to be inspected does not match one of the reference picture patterns. |
