基于白光干涉的ICF靶丸表面缺陷测量方法

Measurement Method for Surface Defects on ICF Capsules Based on White Light Interferometry

针对激光惯性约束聚变实验中的靶丸等微球表面缺陷的真实高度测量问题,为解决现有测量方法存在的缺陷跃变处2π整数倍相位缺失问题,提出一种基于垂直扫描白光干涉技术的零位显微干涉测量方法。该方法采用白光球面零位干涉思想,通过垂直扫描球面干涉获取全视场白光干涉图,然后运用七步移相算法及蝙蝠翼校正算法实现靶丸表面缺陷的形貌计算,最后将白光干涉测量法与激光干涉测量法进行对比实验。结果表明,白光干涉法能够有效解决激光干涉法在缺陷跃变处的2π整数倍相位缺失问题,实现靶丸表面缺陷的真实高度测量,从而扩展靶丸类微球表面缺陷的测量范围。

According to the real height measurement of defects on the surface of microspheres such as capsules in laser inertial confinement fusion(ICF)experiments,a null microscopy interferometric measurement method based on vertical scanning white light interferometry is proposed to solve the problem of missing integer multiples of phase 2πat the defect jumps in existing measurement methods.The method adopts the concept of white light spherical null interferometric microscopy,and obtains the full field of view white light interferograms through vertical scanning spherical interference.Then,the seven-step phase-shifting algorithm and the bat-wing correction algorithm are used to calculate the surface defect morphology of ICF capsules.Finally,the white light interferometry is compared with the laser interferometry through experiments and the results show that the white light interferometry can effectively solve the problem of missing integer multiples of phase 2πat the defect jumps,realize the real height measurement of the ICF capsule surface defects,and extend the measurement range of microsphere surface defects.