Probing Human Vision with Orbital Angular Momentum of Light

“导言：激光和光学在生物医学应用中得到了广泛的应用，特别是在眼部健康方面。偏振光已经得到了广泛的研究，但在将偏振光的波前模式加工成螺旋结构，以研究其在生物医学应用中的功效方面，还存在着深刻的研究空白。具有轨道角动量（OAM）的偏振光可以具有更高的灵敏度和分辨率，使这种光的特性优于传统使用的偏振光。特别是与眼健康有关，黄斑内浊状介质散射特性尚未深入研究。方法：本项目的主要目的包括研究和理解具有轨道角动量的偏振光，以及如何为其目的操纵偏振光，以及确定眼部医学成像的最佳参数。将探讨螺旋结构的微小变化对生物细胞的影响以及在灵敏度和分辨率方面的进展。数学建模：为了探索波前变化对显示不同螺旋尺寸的影响，代数公式将描述分布在空间内的OAM变换，包括涉及时间尺度、脉冲宽度和时间重复率尺度的参数。因此，波前形状随时间的演变可以与空间和脉冲在非均匀介质中的重复相结合，以复制传播如何在生物物质中自然发生。因此，在生物相互作用的背景下，可以探索光的OAM对行为的影响。实验研究：使用具有OAM特性的偏振光源将安装在基于Mach-Zehnder的干涉仪中，以研究其对浊状散射介质的影响。为了推进这种方法，制造一个幽灵将被用来演示这种偏振光对真实生物物质的影响。尺寸和属性应与人眼平行，并将通过CAD软件和3D打印设备制造，以验证前一步的理论数学模型。要考虑的幻像属性有：预定义的手性双折射属性。散射特性。吸收特性。结合上述步骤的理论研究和实验研究结果，可以评估偏振光与OAM的使用在生物医学方法中的应用，特别是在眼健康方面的应用。对一种新的光学成像技术进行了评价。该装置可用于组织的诊断和表征，具有最佳的灵敏度和分辨率。在研究光的OAM对黄斑的结构影响后，可以对视网膜和黄斑进行筛查，以诊断DR和AMD，并可能对其进行治疗。意义：在生物医学应用中使用光的OAM的探索将得到证实，以及黄斑内发现的浊状散射介质特性及其对OAM偏振光的响应的确定。DR和AMD是严重影响生活质量的疾病，因此一种能够通过改变光波阵面来有效诊断和治疗这些疾病的成像设备将对眼科领域产生巨大影响。结论：通过理论和物理模型的合作，实验将展示OAM偏振光的革命性发现，以及它如何诊断和治疗视网膜疾病，如AMD和DR，随后可以开发成一种新的光学成像设备，具有很高的特异性。”

"Introduction: Lasers and optics have been applied in biomedical applications frequently and at great lengths particularly for ocular health. Polarised light has been researched extensively yet there is a profound research gap within manipulating the wavefront pattern into helical structures, to investigate their efficacy for biomedical applications. Polarised light with orbital angular momentum (OAM) can have greater sensitivity and resolution making this light property superior to conventionally used polarised light. Specifically in relation to ocular health, turbid-like media scattering properties located within the macular have not been investigated in depth.Method: The main objectives concerning the project includes the research and comprehension of polarised light with orbital angular momentum and how it can be manipulated for its purpose as well as determining the optimal parameters for ocular medical imaging. The small alterations in the helical structure effect on biological cells and the advancement in sensitivity and resolution will be explored. Mathematical Modelling: To explore the effect of alterations of wavefronts to manifest varying helical sizes, algebraic formulations will describe the OAM transformation which are distributed within space and including parameters involving time scales, pulse width and time repetition rate scales. Consequently, wavefront shape evolution against time can be depicted coupled with space and repetition of pulses within inhomogeneous media to replicate how the propagation would naturally occur in biological matter. Thus, the behavioural influence of OAM of light within a biological interaction context can be explored. Experimental studies: Using a polarised light source with OAM characteristics will be installed within a Mach-Zehnder based interferometer to study its effect on turbid-like scattering media. To propel this method, the fabrication of a phantom will be used to demonstrate the effects such polarised light will have on real biological matter. The size and properties shall run parallel to the human eye and will be fabricated via a CAD software and 3D printing facility to validate the theoretical mathematical model from the previous step. The properties to consider for the phantom are: Predefined chiral Birefringence properties. Scattering properties. Absorption properties. Evaluation of OAM of light for diagnosis of retinal diseases Coupling the results of theoretical studies and experimental studies of the steps mentioned, the usage of polarised light with OAM can be evaluated for its application in biomedical approaches, particularly for ocular health. An assessment for a new optical imagining technique can be addressed. The device can be used in diagnosis and characterisation of tissues with optimal sensitivity and resolution. The retina and macular can be screened to diagnose DR and AMD and perhaps treat them also, after investigating the structural impact on the macular due to OAM of light. Significance: The exploration of using OAM of light in biomedical applications will be substantiated as well as the determination of turbid-like scattering media properties found within the macular and its response to polarised light with OAM. DR and AMD are diseases which drastically effect quality of life and thus an imaging device which can effectively diagnose and treat these diseases via alteration of the optical wavefronts will impact the ophthalmology field tremendously. Conclusion: With the collaboration of theoretical and physical models, the experimentations conducted will demonstrate the revolutionary findings of polarised light with OAM and how it may diagnose and treat retinal diseases such as AMD and DR, which can subsequently be developed into a new optical imaging device with great specificity. "