Apparatus for detecting irregularities in the surfaces of materials

摘要

An apparatus for detecting surface irregularities in a moving web is disclosed. The apparatus includes a laser light source, the output beam of which is divided into a plurality of zone scanning beams by an optical network. The plural beams are reflected by a rotating scanner to a series of reflecting surfaces, each oriented at a different angle to stagger the scanning beams. The staggered beams are again reflected from two groups of reflecting surfaces inclined in opposite directions relative to one another for separating the scanning zones covered by the scanning beams.