Design of a self-referenced laser scanning and ranging system

Abstract

The laser scanning and ranging system is a pivotal technology for conducting high-precision multi-dimensional measurements, with diverse applications in remote sensing, satellite formation flying, and surface profilometry. However, the capability to achieve accurate measurement of the current system is limited by the beam-pointing mechanism. Specifically, the rotation angle of the beam-pointing mechanism is too small to achieve zero-position self-calibration, and this mechanism can introduce errors that exceed the precision of distance measurement. Herein, we propose a self-referenced laser scanning and ranging system that can directly determine the measurement origin and avoid motion-induced optical path length errors into the interferometric arms. This system is achieved by placing the reference arm of the measurement system after the beam-pointing mechanism in the optical path. Using a dual-comb ranging system with a precision of ~0.8 μm, we validated the performance of our design through scanning experiments with hollow retroreflectors and surface profile reconstruction of a gauge-block assembly. The experimental results demonstrate that our design achieves accurate measurements without pre-calibration or post-compensation, thereby enhancing its applicability to next-generation space missions.