A concurrent low resolution/high resolution parallel scanning system is provided as an improvement in the scanning process of an inspection system for planar objects, such as large flat plates employed in panel displays, whereby lower resolution defect detection efficiently overlaps and parallels higher resolution defect review and classification stages in which defects are automatically defined and resolved. Although the invention is a valid solution for the more general problem of optically inspecting the surface of a flat article for defects, the invention is particularly useful for detecting pattern defects on large glass plates deposited with integrated-circuits for forming LCD flat panel displays.