| 摘要 |
PURPOSE:To automize the visual inspection easily and detect the specimen defect quantitatively, by a method wherein fluorescent pattern of defect can be solely detected at high S/N by attaching at incident ray side of a photo-electric conversion element. CONSTITUTION:If image of specimen is received directly using a photo-electric conversion element, the output ray is reflected at the specimen surface and quantity of the reflected ray is greater than that of fluorescent secondary ray, thereby halation occurs and the fluorescent pattern cannot be discriminated. Therefore near ultra-violet ray of wave length less than 480nm in the output ray is attenuated using an optical filter to absorb wave length less than 480nm. Further visible ray of wave length except for 530-570nm is attenuated using an optical filter to transmit wave length 530-570nm and absorb other wave length, thereby the fluorescent secondary ray is solely detected at high S/N ratio. In this constitution, the fluorescent pattern in defect is solely detected thereby the defect can be discriminated in a simple image processing irrespective of influence of the background noise. |
