| 摘要 |
PURPOSE:To prevent the misconception on defects by sufficiently reducing the difference at corner sections between a reference image pattern obtained from the design data and a pattern of an object to be inspected without introducing uncertain factors such as the trial-and-error selection of the weighting factor. CONSTITUTION:The binary design image data prepared from the design data of a printed wiring board are corrected by a correcting circuit to obtain the reference image data. The correcting circuit is connected with rounding circuits C1-CN in series, and each rounding circuit is constituted of a corner section correcting operator circuit CCO detecting and rounding corner sections by applying a prescribed mask pattern to a design image pattern and a 3X3 majority decision filter circuit MF smoothing the corrected image pattern. The reference image data obtained by the correcting circuit are compared with the binary image data obtained by reading the wiring pattern of the printed wiring board, and defects of the printed wiring board are detected. |
