INSPECTION DEVICE

PROBLEM TO BE SOLVED: To provide an inspection device capable of performing defect inspection in a dark field inspection mode based on a confocal optical system.SOLUTION: An inspection device includes: an objective lens (10) which projects a scanning beam toward a sample to be inspected and forms a light spot on the sample; light detecting means (16) for detecting reflectance emitted from the sample via the objective lens; phase shifting means (15) which introduces a phase difference by or by an odd-number multiple of in a half side of an optical path in a direction corresponding to a beam scanning direction, and emits a composite beam consisting of two mutually phase-reversed beam portions; and slit means (17) disposed in the optical path between the phase shifting means and the light detecting means and having a slit-shaped opening. Since the light detecting means detects the composite beam emitted from the phase shifting means and passing through the opening of the slit means, the reflectance from the sample is not incident on the light detecting means when scanning a normal portion of the sample, and thus a dark field inspection mode is realized.