| 摘要 |
PURPOSE:To perform highly accurate measurement for a long distance, in the measurement of the cross sectional shape of the plate shaped body, by sequentially moving luminous flux which scans the plate shaped body in the thickness direction, in the longitudinal direction, and measuring the shape from the value of the discontinuous point of the outputs from a light spot position measuring device. CONSTITUTION:A light source 2 and the like spot position measuring device 4 are arranged on both sides of a steel plate 1 having the longitudinal direction X which is perpendicular to the surface of paper, so that they can be moved in the direction X by rails 6 and 7. The light source 2 comprises a laser source 11, a scanner 12, and a concave mirror 13. The position of spot light 14 is changed in correspondence with the rotary angle of the scanner as shown by alternate long and two short dashes lines in the Figure. Therefore, the spot light scans the side of the steel plate in the direction Y. When the spot light is shielded, the light does not reach the light spot position measuring device, and the output of said measuring device becomes discontinuous at this time. When the value of the discontinuous point is obtained with the light source and said measuring device being scanned in the direction X, the cross sectional shape can be measured. |
