Patent ID: 7248352

Claim:
A method for inspecting defects comprising the steps of: illuminating light to an inspection object containing repetitive circuit patterns formed on a surface thereof; detecting an image signal corresponding to transmission light by selectively shielding a diffraction light pattern generated from said repetitive circuit patterns when the illuminating light is reflected from the surface of said inspection object; and detecting the defects existing on the surface of the inspection object by processing the detected image signal, wherein: said selective shielding of said diffraction light pattern in said detecting step is performed by using a micro-mirror array device, each micro-mirror operation of the micro-mirror array device selectively shields the diffraction light patterns by reflecting the diffract light in a direction where a sensor for detecting the image signal corresponding to the transmission light reflected by each micro-mirror operation cannot receive the selective shielding diffracted light patterns, and said selective shielding of said diffraction light pattern in said detecting step includes observing a Fourier transform image as the selective shielding diffracted light patterns in a Fourier transform plane and controlling each micro-mirror operation of the micro-mirror array device in accordance with the Fourier transform image as the selective shielding diffracted light patterns.