General design basis for a final optics assembly to decrease filamentary damage
Sun Xiao-Yana), b) , Lu Xing-Qianga)† 
, Lü Feng-Niana) , Zhang Guo-Wena) , Zhang Zhena) , Yin Xian-Huaa) , Fan Dian-Yuana)
, Lü Feng-Nian