INSPECTING APPARATUS FOR FOREIGN MATTER

摘要

PURPOSE:To enhance the detection ratio of foreign matter by magnifying the light detecting range of a back scattering light detecting part to an object to be inspected in a foreign matter inspecting apparatus. CONSTITUTION:Back scattering light detecting parts 5a-5d are arranged at several places on both sides of the irradiation position of the surface of an object 1 to be inspected with laser beam 3 at a predetermined angular interval. By this constitution, the back scattering beam emitted from the foreign matter on the object 1 to be inspected by the irradiation with the laser beam 3 from a projection part is detected over a wide range and the detection ratio of the foreign matter on the object to be inspected can be enhanced.