| 摘要 |
A device projecting a reference line, wherein at least one part of the reference path may be detected upon passing through by the human eye and/or detectors as a reference line. In conjunction with passing through the reference path, a distance measurement occurs to at least one point on the reference path by transmitting a measurement beam that is parallel or coaxial to the reference beam or using the reference beam as a measurement beam. After receipt of portions of the reflected measurement beam, a signal is derived from said portions and a distance from at least one point is determined from the signal, wherein the guidance along the reference path is repeated at least once more and, upon each instance of passing through the reference path, a distance or distance-related variable is determined for each point. |
