power balance is necessary to icf, including the energy balance and pulse shape uniformity at the target . 90 percent of the output energy of " sg-ii " comes from its double-pass coaxial array main amplifiers, and pulse shape distortion caused by gain saturation also occurs mostly in there . therefore precise control of gain performance of the main amplifiers by avm ( angular variable mirror ) is the key to the precise power balance of " shenguang-ii " “神光?”裝置90的激光能量由同軸雙程主放大器提供,同時增益飽和效應產生脈沖波形畸變也主要發生在主放大器階段,因此應用組合式角變反鏡(avm,angularvariablemirror)獨立精密控制主放大器各路的增益性能是實現“神光?”裝置精密化功率平衡的關鍵。