| 摘要 |
PROBLEM TO BE SOLVED: To adjust the quantity of light of irregular reflection light sources/regular reflection light sources and a transmitting light source and thereby improve the ability to detect the defect of printed matter by providing irregular reflection light sources and regular reflection light sources which are simultaneously turned ON during inspection and illuminate the surface of printed matter from the camera side and a transmitting light source which illuminates the rear face of printed matter from the opposite side. SOLUTION: This illumination device is equipped with an upper and a lower irregular reflection light sources 12A, 12B and a regular reflection light source 14 which illuminate the front face of a continuous printed matter S from the camera 10 side and a transmitting light source 16 which illuminates the rear face of the printed matter S from the opposite side to the camera 10. All these light sources are turned ON for use during inspection. In addition, the quantity of light of the irregular/regular reflection light sources and the transmitting light source 12A, 12B, 14, 16 is adjusted using each of adjusters. In this case, the irregular reflection light sources 12A, 12B contribute mainly to an inspection for the defect of the printed matter, the regular reflection light source 14 for the defective luster of a metal such as aluminum and the transmitting light source 16 for the defects such as pinholes in the printed matter S and The bleaching of the transparent film respectively. Thus, the balanced quantity of light of each of the light sources enables the high accuracy detection of defects to be performed per printed matter S. |
