With the increasing demand for 3D depth information in various industrial applications, light detection and ranging (LiDAR) has been emerged as one of the solutions to measure the distance of objects. However, existing AMCW-based indirect ToF sensors have problems with measurement accuracy since the measured depth is sensitive to unwanted error sources such as ambient light, wide-band random noises, and stray light. In this paper, the effects of such stray light i.e. systematic error source are thoroughly analyzed in a cause-and-effect manner in terms of the signal’s amplitude and measured phase changes. Furthermore, a pre-compensation method to remove the effects of stray light is validated under various practical experimental conditions. According to the experimental results, the proposed pre-compensation method improves the measurement accuracy with mm-level depth error.
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