Popescu G, Dogariu A
Appl Opt. 2001 Aug 20;40(24):4215-21. doi: 10.1364/ao.40.004215.
For describing the fluctuating signal scattered from a multiple-scattering system, diffusive-wave spectroscopy makes use of a diffusion model that provides the path-length distribution of scattered waves for a specific geometry. Using the recently introduced optical path-length spectroscopy, we show that the diffusion model fails to describe wave propagation in the low-order multiple-scattering regime. We propose a new methodology with which to obtain information about the dynamic properties of nondiffusive scattering systems. We use optical path-length spectroscopy to obtain experimentally the path-length distribution of optical waves scattered from dynamic colloids, which are multiply scattering but not in the diffusion limit. The experimental results show that, with this new technique, the accuracy of dynamic measurements is significantly improved in subdiffusive scattering regimes.
为了描述从多重散射系统散射的波动信号，扩散波谱学利用了一个扩散模型，该模型为特定几何结构提供散射波的光程分布。通过使用最近引入的光程谱学，我们表明扩散模型无法描述低阶多重散射 regime 中的波传播。我们提出了一种新方法，用于获取关于非扩散散射系统动态特性的信息。我们使用光程谱学通过实验获得从动态胶体散射的光波的光程分布，这些胶体是多重散射但不在扩散极限内。实验结果表明，使用这种新技术，在亚扩散散射 regime 中动态测量的精度得到了显著提高。
