PURPOSE: To execute quickly and with high accuracy an inspection of a defect by deciding in detail a defect candidate which has been extracted by the first means, by the second means.
CONSTITUTION: An input image pattern is supplied to a defect roughly extracting part 4 through an image input device 2, and A/D converter 3, image patterns of the corresponding parts of two bodies to be inspected are compared, and a defect candidate is extracted roughly. When the rough extraction processing is repeated by a prescribed number of times, and no defect candidate is detected at all, the inspection is ended. On the contrary, if the defect candidate is detected even once, a position where the defect candidate has been generated is stored by a position detecting circuit 5. Subsequently, by a defect minutely extracting part 6, and a feature extracting and comparing circuit 7, only the defect candidate of the position stored before hand is brought to a minute decision processing. In this way, even if the minute decision processing is not executed to all the input image patterns, an inspection of a defect based on the input image pattern can be executed quickly and with a high accuracy.
EJIRI MASAKAZU
YODA HARUO
SAKAWA YUTAKA
SAKAMOTO YUZABURO
