Cai Houzhi, Ye Zeng, Yao Fangding, Lv Chao, Cheng Xiaohan, Xiang Lijuan
Key Laboratory of Optoelectronic Devices and Systems of Education and Guangdong Province, Shenzhen Key Laboratory of Photonics and Biophotonics, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China.
Sensors (Basel). 2025 Aug 28;25(17):5348. doi: 10.3390/s25175348.
Streak cameras, essential for ultrahigh temporal resolution diagnostics in laser-driven inertial confinement fusion, underpin the streak tube imaging LiDAR (STIL) system-a flash LiDAR technology offering high spatiotemporal resolution, precise ranging, enhanced sensitivity, and wide field of view. This study establishes a theoretical model of the STIL system, with numerical simulations predicting limits of temporal and spatial resolutions of ~6 ps and 22.8 lp/mm, respectively. Dynamic simulations of laser backscatter signals from targets at varying depths demonstrate an optimal distance reconstruction accuracy of 98%. An experimental STIL platform was developed, with the key parameters calibrated as follows: scanning speed (16.78 ps/pixel), temporal resolution (14.47 ps), and central cathode spatial resolution (20 lp/mm). The system achieved target imaging through streak camera detection of azimuth-resolved intensity profiles, generating raw streak images. Feature extraction and neural network-based three-dimensional (3D) reconstruction algorithms enabled target reconstruction from the time-of-flight data of short laser pulses, achieving a minimum distance reconstruction error of 3.57%. Experimental results validate the capability of the system to detect fast, low-intensity optical signals while acquiring target range information, ultimately achieving high-frame-rate, high-resolution 3D imaging. These advancements position STIL technology as a promising solution for applications that require micron-scale depth discrimination under dynamic conditions.
条纹相机是激光驱动惯性约束聚变中超高时间分辨率诊断的关键设备,它是条纹管成像激光雷达(STIL)系统的基础——这是一种闪光激光雷达技术,具有高时空分辨率、精确测距、增强的灵敏度和宽视场。本研究建立了STIL系统的理论模型,数值模拟预测其时间分辨率和空间分辨率极限分别约为6皮秒和22.8线对/毫米。对来自不同深度目标的激光后向散射信号进行动态模拟,结果表明距离重建的最佳精度为98%。开发了一个实验性的STIL平台,其关键参数校准如下:扫描速度(16.78皮秒/像素)、时间分辨率(14.47皮秒)和中心阴极空间分辨率(20线对/毫米)。该系统通过条纹相机检测方位分辨强度分布实现目标成像,生成原始条纹图像。特征提取和基于神经网络的三维(3D)重建算法能够根据短激光脉冲的飞行时间数据进行目标重建,最小距离重建误差为3.57%。实验结果验证了该系统在获取目标距离信息的同时检测快速、低强度光信号的能力,最终实现了高帧率、高分辨率的3D成像。这些进展使STIL技术成为动态条件下需要微米级深度分辨的应用的一种有前景的解决方案。