| 摘要 |
PURPOSE:To keep up with the change of a pitch and to detect a defect of clogging of a hole by calculating the number, the position and the like of through holes in the visual field based on the photographed green sheet flat glass, and detecting the defect. CONSTITUTION:A green sheet 2 to be inspected is supplied onto an X-Y table 3 by 12 of a control device 8. The X-Y table 3 moves the sheet 2 towards a photographing camera 5 and further in X, Y directions to position the sheet so that the first inspecting area of the upper surface of the sheet 2 comes right below the camera 5. The illuminating light is cast to the lower face of the sheet 2 by 4, and a plane image 11 of the sheet 2 in the first inspecting area is photographed by 5 in the visual field 50 of the camera 5. An image processor T to which the image 11 is input computes the number, position and area of through holes 9 in the inspecting area based on the image 11. Either when the number is not coincident with the regulating number, or when the position or area of each hole is not within the allowable range, it is so evaluated that the holes 9 in the visual field 50 are defective. |
