Range precision prediction model for three-dimensional laser gated range-intensity correlation imaging

Three-dimensional laser gated range-intensity correlation imaging (GRICI) can obtain long-range 3D images in real time with high resolution by suppressing backscatter and background noise outside the 3D depth of field. Range precision is crucial for evaluating the performance of 3D GRICI. However, traditional range precision models can only estimate it from experimental results, or cannot accurately predict it theoretically due to over-simplified analysis or insufficient theoretical modeling capability. In this paper, we present a range precision prediction model for 3D GRICI based on the law of error propagation and stochastic process analysis. Particularly, we take into account the photo-electronic process and the temporal jitter of a 3D GRICI system. Based on the classic laser range-gated imaging model, the signal-to-noise model, and the compound random distribution, the mean intensity value and the shot noise can be solved. Thus, the range precision within the 3D depth of field can be accurately predicted. We conducted experiments to validate this model. The results demonstrate that its predictions are more consistent with the experimental results compared to the traditional models. The relative error of the traditional models at 13.45 m is 76.9%, while the relative error of the proposed prediction model is only 3.1%. This research can support the design of 3D gated imaging systems.