Opt Lett. 2018 Jun 15;43(12):2945-2948. doi: 10.1364/OL.43.002945.
The image of the photonic jet (also called caustic) formed by a large, transparent, and spherical particle, reconstructed by digital in-line holography, is shown to be similar to the Airy pattern observed at the focus of a diffraction-limited lens. The analysis of this image, real or virtual depending on whether the particle relative refractive index is above or below one, allows characterizing the particle composition via its refractive index. Experiments clearly demonstrate the value of this method for the simultaneous 3D characterization and differentiation of the dynamics, size, and composition of gas, liquid, and solid particles in multiphase flows.
由大尺寸透明球形粒子产生的光子喷流（也称为焦散）的图像，通过数字共线全息术进行重建，其结果类似于在衍射受限透镜的焦点处观察到的艾里（Airy）斑。对该图像的分析（真实或虚拟，这取决于粒子的相对折射率是大于还是小于 1）允许通过其折射率来表征粒子的组成。实验清楚地证明了这种方法的价值，它可以同时对多相流中气体、液体和固体粒子的动力学、尺寸和组成进行 3D 特征化和区分。
