Surface inspecting apparatus

A surface inspecting apparatus for inspecting a surface of an object to be inspected, the surface inspecting apparatus comprising:

• an illuminating unit for emitting illumination light to the surface of the object;
• an imaging unit for taking a picture of the surface of the object illuminated by the illumination light to form an illuminated image of the surface;
• an image processing unit for detecting a defect existing on the surface on a basis of the illuminated image obtained by the imaging unit to output detected information about the defect;
• a surface-sort inputting unit for inputting a sort of the surface to be inspected;
• a surface-position detecting section for detecting positional information about a position of the surface in a transporting direction to transport the object to be inspected;
• a surface-information specifying section for specifying a curved profile of the surface and angular information about an angle of inclination of the surface, corresponding to the sort of the surface obtained by the surface-sort inputting unit and the positional information obtained by the surface-position detecting section;
• and
• positional relationship controlling section for controlling a positional relationship among the illuminating unit, the imaging unit and the surface to be inspected, on the basis of the angular information specified by the surface-information specifying section and the positional information detected by the surface-position detecting section;
• wherein the positional relationship controlling section controls the positional relationship among the illuminating unit, the imaging unit and the surface to be inspected in such a manner that an incident angle of the illumination light on the surface falls within a definite range and the imaging unit receives diffused reflection light of the illumination light reflected by the surface at a reflection angle which is smaller than the incident angle of the illumination light.