DEVICE FOR INSPECTION OF SURFACE DEFECT

摘要

A surface defect inspection apparatus is provided to measure defects of an object with high precision by visualizing the defect using the amplitude and phase components of light. A surface defect inspection apparatus comprises a line scan camera(300) imaging the contrast generated through a differential interference microscope(200), converting it into digital signal and outputting the digital signal; a piezoelectric element(400) which minutely moves an objective lens(240) at nanometer scale according to the depth of an object; a controller(500) which minutely moves the objective lens up and down; and an analysis unit(600) determining the presence of defect on the object surface by comparing the contrast inputted to the line scan camera with that of the normal product.