摘要 |
A defect inspection apparatus and method includes utilizing an irradiation optical system that focuses a beam flux emitted from a laser light source and formed into a slit-shaped beam so as to irradiate the beam onto the surface of the substrate to be inspected, utilizing a detection optical system that detects light from the substrate that has been irradiated with the slit-shaped beam, and utilizing a signal processor that processes a signal output from the detection optical system. The irradiation optical system includes a cylindrical lens for focusing the beam that has been emitted from the laser light source onto the substrate to be inspected, as the slit-shaped beam, wherein the cylindrical lens is disposed so as to obtain a distance between an incidence surface or emitting surface thereof and the slit-shaped beam upon the substrate to be inspected to be equal to a focal distance of the cylindrical lens. |