基于工艺的连续相位板设计

为改善惯性约束聚变(ICF)系统中聚焦光束质量,降低元件的加工难度,建立了基于工艺的连续相位板(CPP)理论设计模型,并从初相选取、相位展开、滤波、焦斑频谱控制等多方面改进了传统的G-S算法,比较分析了传统设计方法和基于工艺设计方法设计的CPP的加工特性和焦斑性能.基于工艺设计的CPP面型光滑,其产生的焦斑顶部均方根(RMS)和能量利用率η分别从传统G-S的62.8%和98.0%改进到16.9%和98.6%,而且有效抑制了10～100 μm的频谱成分.结果表明,基于工艺的CPP设计方法能够较好满足现有工艺约束条件和物理需求.

Process-Based Design of Continuous Phase Plates

A theoretical design model for continuous phase plates (CPP) used in inertial confinement fusion is built to improve the focus beam quality and reduce the difficulty of CPP's fabrication. Moreover, the traditional G-S algorithm is modified through choosing continuous initial phase, phase unwrapping, phase filtering and controlling the frequency spectrum of focal spot. The operational characteristic and the focal spot's performance caused by the CPP designed by traditional G-S algorithm and modified G-S algorithm are analyzed comparatively. The surface designed by the modified method is smoother than the traditional G-S algorithm, and the root mean square (RMS) and capacity usage ratio of the focal spot caused by modified G-S algorithm are 16.9% and 98.6% respectively, which are all better than the traditional method's 62.8% and 98.0%. The 10～100 μm modulations of focal spot are suppressed very well. It shows that the CPP designed by the modified method meets the process restriction and physical specifications very well.