Defect detection apparatus and defect detection method of the periodic structure object

摘要

PURPOSE: To detect a defect promptly with a high reliability by dividing shape parts corresponding to the island part of 1-D picture data into multiple attributes, detecting characteristics quantity of these and comparing them with the reference value of corresponding characteristics quantity. ;CONSTITUTION: At every one scan, picture signal is, by binarizing circuit 3, etc., sent to a characteristics quantity supply block 5 as run length data representing the address of island which is the continuous part of binary data zero. The block 5 performs preliminary decision on island attribute and supplies temporal characteristics quantity, and the data are sent to a line buffer memory 6, and the data of one-scan earlier are sent to the line buffer memory 7. A logical sum calculation block 8 performs logical calculation of the data in the memories 6 and 7 in pixel units, and detects such coupling states as combination, continuation, etc., and then the result is sent to an attribute updating block 9. A characteristics quantity updating block 10, based on the data from the memory 7, etc., updates corresponding characteristics quantity, then it is sent to a characteristics quantity comparison block 11, and compared with the reference value set for each characteristics quantity of each attribute, for the result to be outputted.;COPYRIGHT: (C)1995,JPO