APPARATUS FOR MEASURING A DEFECT OF SURFACE PATTERN OF TRANSPARENT SUBSTRATE

摘要

The present invention relates to an apparatus to measure a defect in a surface pattern of a transparent substrate. More specifically, a substance having small reflectance is patterned on a transparent substrate to make reflectance of the transparent substrate close to 0, even if the reflectances of the transparent substrate and the patterned substance do not have a great difference, to relatively bring about an increase in the reflectance of the patterned substance and increase the reflectance contrast of the patterned substance and the transparent substrate, thereby measuring a surface pattern with higher detection accuracy or measuring the defect of the pattern.