Foreign substance/defect inspection device, image generation device in foreign substance/defect inspection, and foreign substance/defect inspection method

A foreign substance/defect inspection method, comprising the steps of:

• scanning with a light beam by an illumination optical system including optical scanning means, a plurality of light sources, and collimator lens, wherein the optical scanning means performs scanning with a) a light beam obtained by collimating light emitted from the plurality of light sources arranged to be separated linearly, or a light beam obtained by further substantially concentrating a collimated light beam obtained by collimating light emitted from the plurality of light sources arranged to be separated linearly, with respect to at least one or more an inspection surfaces in an inspection object having light scattering property, or b) a light beam obtained by adjustment of narrowing or spreading light emitted from the plurality of light sources arranged to be separated linearly with respect to at least one or more the inspection surfaces in the inspection object having light scattering property;
• receiving a light beam by a light receiving optical system including a plurality of light receiving elements and a lens system, wherein light receiving optical system is arranged in parallel with a scanning direction of the illumination optical system comprising a plurality of pixel units including at least one photodiode such that each light source and each pixel unit have a one-to-one correspondence, the plurality of light receiving elements receiving scattered light, diffused light, or light having intensity after absorption/diffuse reflection, and transmission and diffusion from a foreign substance or a defect in the inspection object after the foreign substance or the defect is irradiated with the light beam transmitted through the inspection surface of the inspection object;
• and causing, by a control unit, a light beam from each light source at any position in a main scanning direction of the illumination optical system to be detected only by a corresponding pixel unit, wherein, a spatial resolution of each pixel unit including the at least one photodiode is equal to or higher than a spatial resolution of the light beam formed by the illumination optical system on the inspection surface of the inspection object.