an automated opto - electronic test system for quality control of two - dimensional elements with high geometric figure density , such as printed circuits , intermediate printed circuit products , and printing tools has a semiconductor image sensor disposed above a compound table having a position sensor which moves the test specimen beneath a lens in a meandering path at a velocity which is known relative to the semiconductor image sensor . the signals from the image sensor are first analyzed in an analog signal pre - precessor to which are connected a number of error recognition circuits operating in parallel each of which produces an error report which is transmitted to an error coordinating circuit . the error reports are therein associated with position coordinates on the test specimen which are supplied by the position sensor of the compound table and stored until a complete scan of the test specimen has been undertaken and are subsequently employed to move the test specimen to the positions at which the errors occur for visual examination such as by magnification . if the test specimen is a printed circuit , tests which are undertaken are a minimum geometry test measuring respective track and insulation widths , a solder eye test and a special geometry test for open and short circuits .