| 摘要 |
PURPOSE:To ensure the automatic detection of defect parts such as flaws in original paper bubbles and foreign materials, which have entered when an emulsion layer is formed, simply without yielding fog, by scanning the surface of color photographic paper by visible light within a specified range of wavelengh, and detecting the change in color of the emulsion layer. CONSTITUTION:Color photographic paper A is conveyed, with the conveying speed being detected by a detecting roll 6 in which a rotary encoder is provided. A signal is outputted so that a shutter 8 is closed in order to prevent the fog at a low speed. To the surface of the photographic paper A, visible light of 550-635nm is sent from an He-Ne laser light source 10. The intensity of the light is decreased by an ND filter 11, and the light is polarized by a rotary scanner 12. The paper is scanned by the light through an Ftheta lens 13. When a defective part 9 exists, the color of the surface of an emulsion layer is changed into the color different from the normal part. Said coloring is detected by a light receiving unit comprising a light receiving part for the diffused reflected light 17 and a light receiving part for proper reflected light 18. The light receiving parts 17 and 18 are operated by a high voltage power source 19, convert the light into electricity, and detects the defect. Thus the inspection is performed without destruction. |
