Patent ID: 6847444

Claim:
A surface inspection apparatus comprising: a light source section for emitting a first luminous flux and a second luminous flux irradiated on the surface of an inspected object; a first irradiation optical system in which the first luminous flux is irradiated on the surface of the inspected object at a first irradiation angle; a second irradiation optical system in which the second luminous flux is irradiated on the surface of the inspected object at a second irradiation angle different from the first irradiation angle; a displacement section for relatively displacing the inspected object and irradiation luminous fluxes of the first and second irradiation optical systems; a light receiving optical system for receiving scattered light of the first luminous flux irradiated by the first irradiation optical system and produced from inspection on the surface of the inspected object and scattered light of the second luminous flux irradiated by the second irradiation optical system and produced from the inspection on the surface of the inspected object; a first light receiving section for converting scattered light of the first luminous flux received by the light receiving optical system into a first light receiving signal; a second light receiving section for converting scattered light of the second luminous flux received by the light receiving optical system into a second light receiving signal; and a signal forming section for forming a measuring data including the positions of foreign matters on the basis of the first light receiving signal and the second light receiving signal, wherein the first light receiving section and the second light receiving section respectively form the first light receiving signal and the second light receiving signal which are different in sensitivity or dynamic range from each other, wherein, in case that data of foreign matter of the first light receiving signal and data of foreign matter of the second light receiving signal exist in a predetermined range, the signal forming section forms data of foreign matter as same foreign matter on the basis of the first light receiving signal and the second light receiving signal.