A surface inspecting apparatus is provided with an illuminating means for
illuminating a repeated pattern formed on the surface of an object to be
inspected by linear polarization; a setting means for setting an angle
formed by a direction on the surface of an incidence plane of the linear
polarization and a repeating direction of the repeated pattern at a
prescribed value other than 0; an extracting means for extracting
polarization components vertical to an oscillation surface of the linear
polarization, from light generated in a specular direction from the
repeated pattern; a light receiving means for receiving the light
extracted by the extracting means, and outputting light intensity of the
specular reflection light; and a detecting means for detecting defects of
the repeated pattern, based on the light intensity of the specular
reflection light outputted from the light receiving means. The setting
means sets the angle formed by the direction on the surface of the
incidence plane of the linear polarization and the repeating direction of
the repeated pattern so that a difference between the intensity of light
from a normal portion on the surface and the light intensity of light
from a defective portion on the surface is at maximum.