| 摘要 |
PURPOSE:To perform measurement efficiently and accurately, by performing triangulation by utilizing a laser range finderprovided with an image sensor device, which collimates laser light and its projected spot. CONSTITUTION:The reflecting point of laser light on a fixed mirror 11 in a reflecting mechanism 9 is made to be a laser-light projecting point. The center of a lens 15 of an image sensor device 7, which is separated from said point in the axial direction of a tubular body 6, is made to be a collimating point. The laser light is projected to the excavating wall of a tunnel from the laser-light projecting point. The actual projected spot at this time is collimated by the image sensor device 7. The image is formed at a position on a photo sensor in correspondence with the collimating angle of the projected spot. The image sensor device 7 outputs the amount of displacement between the imaginary image position corresponding to the collimating angle with respect to a point, which is separated by an imaginary distance from the laser-light projecting point, and the actual image position, as the change in image output. The distance from the laser-light projecting point to the actual projected spot is measured by an operating expression in triangulation. |
