The Study Of Receiving Experimental System Of Array Imaging Three Dimensional Lidar

Three dimensional imaging lidar has many advantages, such as active imaging, high accuracy, large quantity of information and so on. So, it can be widely used in target identification and tracking, terrain mapping, obstacle avoidance, precision non-destructive testing and many other areas. Three-dimensional imaging lidar has broad prospects for military and civilian. Long-distance, high resolution rapid 3-D imaging lidar has been a hot topic. The range gating technology has greatly improved the system range accuracy and real-time, and promotes the development of high-resolution lidar. However, it is still in the early stages of development. Study on long distance rapid high resolution imaging lidar is of great significance for promoting the development of laser remote sensing technology and mastering key technologies of imaging lidar.Consideration the documentation and key domestic device manufacturing and outsourcing situation, the author proposes a polarization modulation range-gated imaging lidar system, which based on the principle of KDP electro-optic crystal polarization modulation. Firstly, it discusses the principles of KDP crystal phase modulator and the three-dimensional image reconstruction method in detail. Then, the optical design and tolerance analysis for the optical receiving system of the lidar system has been made. Furthermore, in the receiving optical system the large aperture optical element’s mounting machine structural characteristics is introduced. The large aperture optical element self-weight deformation and temperature gradients how to affecting the lidar system performance is analyzedfor using the thermal-structural-optical integrated analysis method. Finally, we set up the experimental system and did a three-dimensional imaging verification experimental.Simulation results show that the large aperture optical element’s self-weight deformation does not constitute a hazard to the three-dimensional lidar performance. But, the element radial and axial temperature gradient causes the receiving optical system image quality degradation, which will affect the longitudinal and lateral resolution of lidar system. Within a certain temperature range, select the appropriate detector binning mode, the longitudinal resolution can be guaranteed by sacrificing lateral resolution: axial and radial temperature does not exceed 1℃, detector using 2 × 2binning mode, lateral resolution falling by half, longitudinal distance contrast greater than 0.95.We’re choosing a building as a target to do a three-dimensional imaging experiment. The building isabout one kilometer from the Lidar system. And we obtained it 3-D information with the Lidar system.