Polarimetric Mueller matrix imaging in multiply scattering inhomogeneous birefringent media

光为我们提供了许多关于我们周围环境的有用信息。除了它的波长(颜色)和强度之外，光束的另一个有用的特性是它的偏振态，即垂直于传播方向的电场矢量的方向。当光与物体相互作用时，其偏振态会发生变化。因此，可以通过测量这种变化来获得对象的属性。在这里，我们建议将我们的研究扩展到偏振光与混浊材料的相互作用。这项研究的长期目标是对生物组织进行偏振光评估。光在这种材料中所经历的大量偏转将显著扰乱它的偏振。然而，我们和其他人已经证明，在这样的多次散射中，仍然可以保留惊人数量的有用偏振信息。因此，所提出的方法将优化混浊介质中偏振效应的测量和分析。然后，这些方法可以用来表征混浊系统，如行星大气、生物组织或无定形半导体。还建议研究介质“双折射”的影响。这指的是一些材料的结构不对称/微建筑组织，这导致它们以不同的方式与偏振光相互作用。长期以来，偏振测量一直被用于透明介质或薄膜材料，以探索其结构的细节。这项拟议的工作是新颖的，因为它的意图是量化光学厚度浑浊介质中的这些结构不对称。在生物医学领域的重要意义源于许多生物组织的不对称性质，以及由于疾病进展或治疗而导致的微结构重排。然后，我们的偏振光方法可以报告泌尿外科(膀胱壁各向异性，梗阻性膀胱疾病中的结构-功能关系)、心脏病(梗死和干细胞再生治疗后的心肌重构)和肿瘤学(乳腺癌沿肿瘤细胞外基质中各向异性路线的转移)的组织功能状态和组织存活率。

Light provides us with much useful information about our surroundings. In addition to its wavelength (colour) and intensity, another useful property of an optical beam is its polarization state, or the orientation of the electric field vector perpendicular to the propagation direction. When light interacts with an object, its polarization state will be changed. Hence the properties of the object can be obtained by measuring this change. Here, we propose to extend our research into polarized light interactions with turbid materials. The long-term goal of the research is to perform polarized light assessment of biological tissues. The numerous deflections experienced by the light in such materials will significantly scramble its polarization. However, we and others have shown that a surprising amount of useful polarization information can be still retained upon such multiple scattering. The proposed methodology will thus optimize measurements and analysis of polarization effects in turbid media. These methods can then be used to characterize turbid systems such as planetary atmospheres, biological tissues, or amorphous semiconductors. It is also proposed to investigate the effects of the medium "birefringence". This refers to the structural asymmetry / microarchitectural organization of some materials, which causes them to interact with polarized light in distinctive ways. Polarization measurements have long been used in TRANSPARENT media or thin materials (thin films) to probe the details of its structure. The proposed work is novel in its intent to quantify these structural asymmetries in optically thick TURBID media. Significance in the biomedical arena stems from the asymmetric nature of many biological tissues, and microstructural rearrangements as a result of disease progression or treatments. Our polarized light approach can then report on tissue functional status and tissue viability in urology (bladder wall anisotropy, structure-function relationship in obstructed bladder disease), cardiology (heart muscle remodelling following infarct and stem-cell regenerative therapies) and oncology (breast cancer metastatic spread along anisotropic routes in the tumour extracellular matrix).