| 摘要 |
PROBLEM TO BE SOLVED: To provide an appearance inspection device that can detect a crack of a surface of an inspected body with high sensitivity even if the crack thereof is shallow.SOLUTION: An appearance inspection device according to the present invention is a device that inspects a surface of a planar inspected body, and the appearance inspection device comprises: (a) a light source that irradiates the surface of the inspected body with a plurality of mutually adjacent parallel linear light; and (b) a linear light reception unit that is arranged at a location where any of the plurality of mutually adjacent parallel linear light reflected upon the surface of the inspected body or passing through the inspected body is received or at a location in the vicinity of the location, and is parallel to the linear light. If there is a surface crack of the inspected object, when the plurality of linear light with which the surface of the inspected body irradiated is reflected at a portion of the crack or passes through the portion thereof to enter the light reception unit, the plurality of linear light is incident upon the light reception unit at a mutually different angle. Thus, even if the crack is shallow, a defect of the crack can be detected by any of reflection light/transmission light, which in turn can detect a defect of the surface of the inspected body with high sensitivity as a whole. |
