| 摘要 |
PURPOSE: To realize a plurality of illumination methods by one optical system, and exact classification of defects and to realize a judging function similar to the human ability of inspection by visual observation. CONSTITUTION: In the equipment for detecting a defect by casting an illuminating light on the surface S of an object of inspection whereon a lattice pattern is formed, an illuminating optical system 2 which casts on the surface of the object of inspection the illuminating light in the direction intersecting the aforesaid pattern perpendicularly in a prescribed sphere of illumination of the surface from an oblique position and converges a diffracted light generated on the surface to a prescribed position is provided. This equipment has image input means 3 and 4 which pick up an image of the aforesaid sphere of illumination from a position being apart from the aforesaid surface of the object of inspection in such a degree as not to be illuminated by the illuminating light and excluding the position of convergence of the diffracted light and/or the point of convergence thereof, and a display means 7 which visualized image signals of a diffracted light zone outputted from the image input means 3 and 4. |
