发展了背光阴影成像技术, 用于诊断透明ICF冷冻靶冰层内表面质量。分析了单层球壳阴影图像中形成亮环的物理机制。用光学追迹软件Tracepro模拟产生了透明单层球壳的阴影图像, 用于研究亮环位置与球壳厚度及折射率的关系。建立了背光阴影成像实验装置, 获得了透明单层球壳具有明显亮环的实验阴影图像。编制了阴影图像处理软件, 获得了靶丸内表面1维功率谱曲线, 并据此计算出靶丸内表面均方根粗糙度。理论分析、软件模拟及实验研究均表明, 背光阴影成像技术是透明冷冻靶冰层内表面质量的有效诊断方法。

A backlit shadowgraphy technique has been developed, which can be used for nondestructive characterization of ice layer’s inner surface quality for transparent ICF capsules. The physics of the bright band formation for single-layer shell is analyzed by optical theory. With raytrace code, Tracepro, simulated shadowgraphs of transparent single-layer shells are produced to investigate the relation between bright-band position and thickness or refractive index of shells. A setup has been established for backlit shadowgraphy, and experimental shadowgraphs of transparent single-layer shells are obtained, which have a distinct bright band. A code has been developed to analyze shadowgraphs, and the shell’s inner surface power spectrum (1-D) is obtained, then its RMS surface roughness is calculated. These analyses in theory, simulation and experimental results prove the validity of the technique.