A method is presented for simultaneously inferring both the refractive index and the size of a particle with extended interferometric particle imaging technique. The optical system of extended IPI with opposite two-sheet illumination at dual scattering angles is laid out for the experiment. The size of a particle is evaluated by the interference fringe recorded at the scattering angle of 90°, which is from the two reflected lights with two counter-propagating sheet illuminations. And then the refractive index is calculated by the fringe pattern recorded in the side scattering angle region with one of two-sheet illumination when combined with droplet size determined. Experiments on the polystyrene microsphere and water droplet suggest that the method presented herein is promising for many relevant applications, such as fuel combustion and environmental monitoring, in accurately measuring both the particle size and its refractive index.

中文翻译：

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通过扩展干涉粒子成像技术同时获取粒径和折射率。

提出了一种利用扩展干涉粒子成像技术同时推断粒子的折射率和尺寸的方法。为实验设计了扩展IPI的光学系统，该光学系统在双散射角下具有相反的两片照明。颗粒的大小通过以90°散射角记录的干涉条纹来评估，该干涉条纹来自两次反射光和两次反向传播的片状照明。然后，当结合确定的液滴尺寸时，通过记录在侧面散射角区域中的条纹图案（具有两张照明之一）来计算折射率。在聚苯乙烯微球和水滴上进行的实验表明，本文介绍的方法可用于许多相关应用，