激光惯性约束聚变驱动器终端光学系统中束匀滑器件前置的条件研究  

Study on the frontal condition for continuous phase plate in inertial confinement fusion driver

作　　者：姚欣[1] 高福华[1] 张怡霄[1] 温圣林[2] 郭永康[1] 林祥棣[1] 

机构地区：[1]四川大学物理科学与技术学院,成都610064 [2]成都精密光学工程研究中心,成都610041

出　　处：《物理学报》2009年第5期3130-3134,共5页Acta Physica Sinica

基　　金：国家高技术研究发展计划(863)项目(批准号:804)资助的课题~~

摘　　要：对激光惯性约束聚变(ICF)驱动器终端光学系统中连续相位板(CPP)的位置优化进行了研究.根据高强度激光非线性及微扰传输理论计算了CPP前置时激光通过频率转换系统以后的近远场光束特性和系统的三倍频转换效率.研究发现,前置于基频光路的CPP对三倍频转换效率和出射光束特性均有影响,但只要远场圆形焦斑直径小于0.5mm,三倍频转换效率的下降与出射光束通量对比度的上升均在容许范围之内,同时远场焦斑形态和能量集中度也符合设计要求.对于实现远场小焦斑匀滑的CPP前置于ICF的基频光路中进行光束匀滑和整形,不会对ICF系统的正常运行产生影响.Optimal placement for continuous phase plate （CPP） in terminal optical system of the Inertial Confinement Fusion （ICF） driver has been studied. Based on non-linear perturbation and transmitting theory of high power laser, the optical characteristics in near and far fields as well as third harmonic conversion efficiency after passing throngh the frequency conversion system has been calculated. As a result, the third harmonic conversion efficiency and optical characteristics of the emergent light beam are influenced by the CPP which is placed before the frequency conversion system. But if the diameter of the round focal spot in far field is smaller than 0.5 mm, the decline of the third harmonic conversion efficiency and the rise of contrast ratio are within permitted range, the shape of focal spot in far field and the encircled energy of focal spot also accord with the design requirement at the same time. The CPP which enables small focal spot in far field, when located in the beam path of fundamental frequency of ICF system to smooth and shape the light beam, will not exert influence on the normal running of ICF system.

关 键 词：连续相位板 束匀滑元件 惯性约束聚变 光束通量对比度 

分 类 号：TL632.1[核科学技术—核技术及应用]