| 摘要 |
PURPOSE:To accurately calculate each cross-sectional shape of a tunnel directly after blasting, by reflecting laser light from a laser oscillation tube at the wall surface of the tunnel and measuring the angle of a solid image pick-up camera receiving the reflected beam. CONSTITUTION:The titled apparatus is constituted of a laser transit 1, a pentagonal prism 10, an operation apparatus 20 and a tunnel cross-sectional distance measuring machine 30. A laser oscillation tube 37, a prism 38 and a solid image pick-up camera 39 are arranged on a stand 34 on one line and laser light B emitted from the laser oscillation tube 37 is refracted at a right angle by the prism 38 and reflected by the laser mark set to the appropriate position of a tunnel while the reflected laser light is caught by the camera 39. |
