Patent ID: 7847928

Claim:
An inspection device for inspecting defects or foreign matters on a surface of an inspection object, comprising: a light source for irradiating a luminous flux to said inspection object; an optical system for guiding reflected and scattered light reflected from said inspection object; a photoelectric image sensor having a plurality of photoelectric cells arranged, for converting said reflected and scattered light guided to electric detection signals; a detection signal transfer unit having channels each constituted by a signal correction unit, an A/D converter and an image formation unit, and corresponding to each of a plurality of regions formed by dividing said photoelectric image sensor, respectively; and an image synthesis unit for forming an image of the surface of said inspection object by synthesizing partial images outputted by said detection signal transfer unit; said inspection device inspecting defects or foreign matters of the surface of said inspection object by processing said synthesized image; wherein said detection signal transfer unit has a detection signal correction function capable of bringing a detection signal from said photoelectric cell close to a reference target value of a reference detection signal intensity determined for each of said channels.