Vorontsov Mikhail, Filimonov Grigory, Ovchinnikov Vladimir, Polnau Ernst, Lachinova Svetlana, Weyrauch Thomas, Mangano Joseph
Appl Opt. 2016 May 20;55(15):4170-85. doi: 10.1364/AO.55.004170.
The performance of two prominent laser beam projection system types is analyzed through wave-optics numerical simulations for various atmospheric turbulence conditions, propagation distances, and adaptive optics (AO) mitigation techniques. Comparisons are made between different configurations of both a conventional beam director (BD) using a monolithic-optics-based Cassegrain telescope and a fiber-array BD that uses an array of densely packed fiber collimators. The BD systems considered have equal input power and aperture diameters. The projected laser beam power inside the Airy size disk at the target plane is used as the performance metric. For the fiber-array system, both incoherent and coherent beam combining regimes are considered. We also present preliminary results of side-by-side atmospheric beam projection experiments over a 7-km propagation path using both the AO-enhanced beam projection system with a Cassegrain telescope and the coherent fiber-array BD composed of 21 densely packed fiber collimators. Both wave-optics numerical simulation and experimental results demonstrate that, for similar system architectures and turbulence conditions, coherent fiber-array systems are more efficient in mitigation of atmospheric turbulence effects and generation of a hit spot of the smallest possible size on a remotely located target.
通过波光学数值模拟，针对各种大气湍流条件、传播距离和自适应光学（AO）缓解技术，分析了两种著名的激光束投影系统类型的性能。对使用基于单片光学的卡塞格伦望远镜的传统光束导向器（BD）和使用密集排列的光纤准直器阵列的光纤阵列BD的不同配置进行了比较。所考虑的BD系统具有相等的输入功率和孔径直径。目标平面上艾里斑尺寸圆盘内的投射激光束功率用作性能指标。对于光纤阵列系统，考虑了非相干和相干光束合成方式。我们还展示了在7公里传播路径上使用配备卡塞格伦望远镜的AO增强光束投影系统和由21个密集排列的光纤准直器组成的相干光纤阵列BD进行并排大气光束投影实验的初步结果。波光学数值模拟和实验结果均表明，对于类似的系统架构和湍流条件，相干光纤阵列系统在减轻大气湍流影响以及在远程目标上生成尽可能小尺寸的命中点方面更有效。
