AOI inspection to today's machine vision advanced biological mechanisms vision algorithms to simulate the human eye perceives be closed contour detection algorithms, contour line to obtain information on the PCB, and the establishment of contour detection logic-based. This machine for testing during the manufacturing process (bare board) circuit open, short, copper slag, copper protrusions, notches or the like defects. It has a complete line of inspection parameters, strong core defect detection capabilities; false point control, super error correction and so on.