Patent ID: 7110105

Claim:
An apparatus for inspecting pattern defects, comprising: a laser beam source for emitting a laser beam; an adjuster for adjusting a light-amount of the laser beam emitted from said laser beam source; a coherence reducer for lowering coherency of the laser beam; an illumination system for irradiating upon a sample the coherence reduced laser beam; an image-former for forming an image of reflection light reflected from the sample by the irradiation of the coherence reduced laser beam; a detector which includes an image sensor for receiving the image of the reflection light formed by the image-former and for converting it into a detected image signal; and an image processor for detecting defects on patterns formed on the sample by processing the detected image signal; wherein the image-former includes an objective lens unit and an imaging lens unit, and the imaging lens unit includes plural lenses, at least one of the plural lenses being movable along an optical axis of the imaging lens unit so that a magnification of the image is changeable.