SYSTEM FOR RECOGNIZING POLARITY MARK

PURPOSE:To recognize a polarity mark without receiving the influence of a character shape in a mold. CONSTITUTION:The memory 10 of a picture processor 1 stores picture data inputted from an overhead camera 2. A picture data segmenting part 11 takes out a part lighter than a threshold in the allowable range of picture data stored in the memory 10. A peripheral length calculating part 12 calculates the peripheral length of the part taken out by the picture data segmenting part 11. An area calculating part 13 calculates the area of the part taken out by the picture data segmenting part 11. A peripheral length comparing part 16 compares peripheral length calculated by the peripheral length calculating part 12 with the peripheral length of the polarity mark stored in a polarity mark peripheral length register 14. An area comparing part 17 compares the area calculated by the area calculating part 13 with the area of the polarity mark stored in a polarity mark area register 15. A normal/defective discriminating part 18 discriminates whether an object to be inspected is normal or defective from compared result in the peripheral length comparing part 16 and compared result in the area comparing part 17.