| 摘要 |
PURPOSE:To detect black defect in in-line manner by, while a lenticular lens sheet is moved, imaging under bright transmission field-of-sight lighting by linear area imaging means on the front side and both sides, for focussing on the imaging plane of respective imaging means, by imaging means, so that the imaged signal is image-processed. CONSTITUTION:The lenticular lens sheet 4 is moved at constant speed in the direction of arrow in the figure. With a lens 2a, the image of the sheet 4 is imaged on the imaging plane of a CCD camera 1a, and the camera 1a images imaging field-of-sight 6 on the straight line in the width direction of the sheet 4 from its front side. With lenses 2b and 2c, CCD cameras 1b and 1c swing- image the imaging field-of-sight 6 on the straight line in the width direction of the sheet 4 from the left and right, for focusing on respective imaging planes, and a light source 3 lights the sheet 4 in the manner of bright transmission field-of-sight. The picture signals obtained as such of the cameras 1a and 1b are processed with primary and secondary differentiating processes, so that defect is specified based on the changes in signals. With this, the in-line inspection for the black defect of sheet 4 viewed in three directions at the same becomes possible. |
