A technique for developing an inspection program for a circuit board to be
run on an AOI system includes determining a characteristic, such as
average gray level, of each window of the circuit board. The positions of
the windows are varied slightly to simulate expected errors in the
placement of the windows relative to the circuit board. After varying the
positions of the windows, the characteristic of each window is determined
again. Different values of the characteristic corresponding to slightly
different positions are compared for each window. Values that
substantially change for a window indicate a strong sensitivity to
position. These windows may be reported to a programmer for corrective
action.