Patent ID: 8854613

Claim:
A surface defect inspection apparatus comprising: a light source that emits light to a first position on a surface of a target at an angle inclined with respect to the surface of the target; a first photodetector that detects first reflected light of the light from the light source, the first reflected light being reflected at the first position, a second photodetector that detects second reflected light of the light from the light source, the second reflected light being reflected at a second position on the surface of the target, the second position being different from the first position and closer to the light source than the first position and being separated vertically from the surface of the target by a given distance; and a determining unit that determines whether or not foreign matter is present on the surface of the target on a basis of detection results obtained from the first photodetector and the second photodetector, the determining unit determining that the foreign matter with a predetermined height or more is present on the surface of the target when the first reflected light is not detected by the first photodetector and the second reflected light is detected by the second photodetector.