| 摘要 |
PURPOSE:To increase the degree of freedom in the disposition of a camera while enhancing the measurement accuracy of edge position by correcting the depth of a board member depending on each edge position of the board member with respect to an image pickup camera. CONSTITUTION:At first, the opposite edge positions (Xt, Y) (Xb, Y) are compared with the projected position (O, Y) of a camera unit 3 on a carrying roll 1. When the opposite edge positions are spaced apart in same direction from the projected position (O, Y), one edge (Xt, Y) detects the upper end of a thick plate slab 2 whereas the other edge position (Xb, Y) detects the lower end of the stab 2. Consequently, only the edge position (Xt, Y) remote from the projected position (O, Y) is corrected depending on the depth (h) of the slab 2. In other words, correct distance X' between the projected position (O, Y) and the edge (Xt', Y) can be determined according to a formula; X'=X(H-h)/H, where H represents the distance between the camera and the carrying roll 1. |
