Polarized light assessment of multiply scattering heterogenous birefringent media

多重散射异质双折射介质的偏振光评估

• 批准号: RGPIN-2018-04930
• 负责人: Vitkin, Alex
• 金额: $ 3.64万
• 依托单位: University of Toronto
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=713362
• 关键词: Polarized; light; assessment; multiply; scattering

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. Polarization measurements have long been used in TRANSPARENT media or thin materials (thin films) to probe the details of their structure and composition. The proposed work is novel in its use of polarized light for quantifying optically thick TURBID media. 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 still be retained even after a significant number of (multiple) scattering events. Sensitive measurement and accurate quantification of this surviving polarization signal then yields unique characteristics and "signatures" of the interrogated material. The proposed methodology will thus further optimize measurements and analysis of polarization effects in such interesting but technically challenging turbid media. The long-term goal of the research is to perform accurate polarized light assessment of biological tissues. Although not explicitly pursued here, the developed polarized methods may also find applications in non-biological domains such as remote sensing of turbulent flows and planetary atmospheres, underwater characterization of objects, and inspection in harsh (e.g., radiation damage) environments. The proposed scientific and technical developments will thus (1) optimize polarimetric imaging methods as a rapid guidance technology for accurate assessment of tissue pathology (e.g., tumour margin detection via polarimetrically-guided mass spectrometry during cancer surgery), (2) report on tissue functional status and viability in difficult-to-reach body locations (e.g., inside of the bladder wall in urology), and (3) enable further understanding of linear and non-linear polarized light turbid media (biological tissue) interactions for improved tissue microscopy. Overall, this research program will further advance the promising optical technology based on the unique strengths and information content of polarized light, towards enabling a variety of exciting and important biomedical applications.

Light为我们提供了有关周围环境的许多有用的信息。除了其波长（颜色）和强度外，光束的另一个有用的特性是其极化状态，或垂直于传播方向的电场矢量的方向。当光与对象相互作用时，其极化状态将被更改。因此，可以通过测量此更改来获得对象的属性。 极化测量长期以来一直用于透明介质或薄材料（薄膜），以探测其结构和组成的细节。提出的工作是使用偏振光来量化光学较厚的浑浊介质的新颖新颖的。这些材料中光经历的众多偏转将大大扰乱其极化。但是，我们和其他人表明，即使在大量（多个）散射事件发生后，仍然可以保留大量有用的极化信息。然后，对该存活的极化信号的敏感测量和准确量化会产生询问材料的独特特征和“特征”。 因此，所提出的方法将进一步优化这种有趣但技术上具有挑战性的浑浊介质中极化效应的测量和分析。该研究的长期目标是对生物组织进行准确的极化光评估。尽管在这里没有明确追求，但开发的两极化方法也可能在非生物域中找到应用，例如湍流流和行星气氛的遥感，物体的水下表征以及在严酷的环境（例如辐射损害）环境中进行检查。 The proposed scientific and technical developments will thus (1) optimize polarimetric imaging methods as a rapid guidance technology for accurate assessment of tissue pathology (e.g., tumour margin detection via polarimetrically-guided mass spectrometry during cancer surgery), (2) report on tissue functional status and viability in difficult-to-reach body locations (e.g., inside of the bladder wall in urology), and (3) enable further understanding of线性和非线性偏振光浊度介质（生物组织）相互作用，以改善组织显微镜。 总体而言，该研究计划将基于两极光的独特优势和信息内容进一步推进有希望的光学技术，以实现各种令人兴奋和重要的生物医学应用。