METHOD AND APPARATUS FOR INPUT OF IMAGE OF FLAT SURFACE

摘要

PROBLEM TO BE SOLVED: To provide a method and an apparatus wherein an image can be input with high accuracy when illumination light with reference to the surface of an object to be inspected is diffused by a diffuser panel so that the surface of the object can be image-input with high resolution. SOLUTION: While the object W comprising a flat surface is being irradiated with the illumination light from a light source (an illumination part) 14, the surface is imaged by a camera 10 so as to input the image. At this time, the diffuser panel 16 which diffuses the illumination light from the light source is arranged between the surface of the object W and the light source 14, and the diffuser panel 16 is set in a position at an optical limit distance in which irregularities in a luminance generated in the input image caused by the surface roughness of a blank are substantially eliminated with reference to the surface of the object.