AUTOMATIC DETECTION DEVICE FOR PRINT DEFECT ON METALIZED STRIP OR OTHER OPTIONAL PRINT BASE MAINLY COMPOSED OF SURFACE IN MIRROR REFLECTING COLOR

摘要

PROBLEM TO BE SOLVED: To provide an automatic detection device for an initial print defect on a metalized strip. SOLUTION: This print defect automatic detection device 1 is equipped with a video camera 55 having a varifocal lens 56, and has an illumination unit 10 automatically movable on an arm 30. The video camera 55 photographs continuously a part comprising a variable-size format 7 of a metalized strip 3 through a translucent filter 47 installed obliquely before the lens 56. Illumination of the strip 3 part is executed by direct illumination flash lamps 12, 14 and indirect illumination flash lamps 11, 13. The flash lamp 13 has a translucent flat diffuser 27 trained in the filter 57 direction. The flash lamp 11 is trained in the surface direction of an opaque concave diffuser 25 for encircling the translucent filter 57. The diffuser 25 and the lens 56 are combined mechanically and optically by a sleeve 26.