A 1178 J near diffraction limited 527 nm laser is realized in a complete closed-loop adaptive optics (AO) controlled off-axis multi-pass amplification laser system. Generated from a fiber laser and amplified by the pre-amplifier and the main amplifier, a 1053 nm laser beam with the energy of 1900 J is obtained and converted into a 527 nm laser beam by a KDP crystal with 62% conversion efficiency, 1178 J and beam quality of 7.93 times the diffraction limit (DL). By using a complete closed-loop AO configuration, the static and dynamic wavefront distortions of the laser system are measured and compensated. After correction, the diameter of the circle enclosing 80% energy is improved remarkably from 7.93DL to 1.29DL. The focal spot is highly concentrated and the 1178 J, 527 nm near diffraction limited laser is achieved.

中文翻译：

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基于完整闭环自适应光学控制的离轴多通放大激光系统的1178 J、527 nm近衍射限制激光器

在一个完整的闭环自适应光学 (AO) 控制的离轴多通放大激光系统中实现了 1178 J 近衍射限制 527 nm 激光器。由光纤激光器产生，经前置放大器和主放大器放大，得到能量为1900 J的1053 nm激光束，经KDP晶体转换成527 nm激光束，转换效率为62%，1178 J光束质量为衍射极限 (DL) 的 7.93 倍。通过使用完整的闭环 AO 配置，可以测量和补偿激光系统的静态和动态波前畸变。修正后，包围80%能量的圆的直径由7.93DL显着提高到1.29DL。焦点高度集中，实现了 1178 J、527 nm 近衍射限制激光。