Modeling and simulations of a three-dimensional ghost imaging method with differential correlation sampling.

The quality of depth maps acquired by a time-of-flight three-dimensional ghost imaging (3DGI) system is limited by dynamic ambient light and electrical noise. We developed a novel method that integrates the differential-correlation-sampling (DCS) method and a modulated continuous-wave laser source to realize the 3DGI and reduce the noise influence. The simulation results for the proposed method, DCS-3DGI, verify its feasibility. The analysis of mean-square-error, peak signal-to-noise ratio, structural similarity index measure, and edge preservation index demonstrates a superior anti-interference performance than conventional 3DGI methods.

A Fast Calibration Method for Photonic Mixer Device Solid-State Array Lidars.

The photonic mixer device (PMD) solid-state array lidar, as a three-dimensional imaging technology, has attracted research attention in recent years because of its low cost, high frame rate, and high reliability. To address the disadvantages of traditional PMD solid-state array lidar calibration methods, including low calibration efficiency and accuracy, and serious human error factors, this paper first proposes a calibration method for an array complementary metal⁻oxide⁻semiconductor photodetector using a black-box calibration device and an electrical analog delay method; it then proposes a modular lens distortion correction method based on checkerboard calibration and pixel point adaptive interpolation optimization. Specifically, the ranging error source is analyzed based on the PMD solid-state array lidar imaging mechanism; the black-box calibration device is specifically designed for the calibration requirements of anti-ambient light and an echo reflection route; a dynamic distance simulation system integrating the laser emission unit, laser receiving unit, and delay control unit is designed to calibrate the photodetector echo demodulation; the checkerboard calibration method is used to correct external lens distortion in grayscale mode; and the pixel adaptive interpolation strategy is used to reduce distortion of distance images. Through analysis of the calibration process and results, the proposed method effectively reduces the calibration scene requirements and human factors, meets the needs of different users of the lens, and improves both calibration efficiency and measurement accuracy.