Collaborative Research: Dynamic Manipulation of Micro-scale Liquid-Liquid Interfaces within Complex Droplets for Tunable Optics

可以实时调谐和调整的光学材料在许多应用中变得重要。这些包括显示技术、紧凑型成像设备、生物医学传感器和医疗点诊断工具。液体具有许多对可调谐光学有利的性质。液体是可变形的，具有广泛的可调特性，并且具有具有可变曲率的超光滑表面。这些特性在可调谐微透镜中可能特别有益。在这个项目中，研究人员将研究复杂的液滴如何作为可调光学材料。在这里，复杂的液滴将由两到三个不相容的油在一个含水的外部相中组成。将使用实验以及分析和计算建模相结合的方法。其目的是全面了解实现基于流体的新型光学技术的机会。微米级光学元件对器件和仪器的小型化做出了重要贡献。它们已被用于集成成像和3D显示器、空间光调制器、内窥镜、全光相机和太阳能聚光器。基于数字微镜显示器和由液晶显示器实现的连续可重新配置的吸收像素技术的动态可切换反射微光学使光学技术取得了革命性的进步。同样，动态折射微光学有望补充和扩展现有微光学器件的能力。虽然液体还不是光学工程师工具箱中的主要产品，但在需要可调的应用中，液体具有极大的灵活性、设计优势、小型化前景和制造优势。尽管在光学设备中使用液体很有希望，但液体的延展性和对许多刺激的敏感性使得液体对于可调光学元件来说是如此宝贵，这也使得它们很难以光学应用所需的精度进行控制。深入了解液体界面操作策略以微调流体光学元件，以及控制复杂多相系统中的流体-流体界面的新方法，对于光流控器件的发展至关重要。在这项合作工作中，研究人员旨在证明，仔细设计多相乳胶液滴的组成和形态为形成可调透镜和微尺度全内反射模块提供了一种强大的策略。这项研究通过探索如何使用包含多个可重新配置的流体界面的液滴来控制透镜、校正光学像差并通过全内反射实现高效的光谱色散，从而突破了当前液体光学的界限。了解如何独立或串联处理液体界面，以动态调整复杂液滴的光学行为，将使流体作为光学元件得到应用。通过这次合作，该团队的目标是将光学理论与增强对如何操纵多相液体的理解结合在一起，目标是扩大复杂流体在动态光学材料领域中所起的作用。考虑到本提案中使用的复杂液滴可以很容易地制造和重新配置，研究人员将使用流体光学材料作为教学工具，向K-12学生和教育工作者介绍表面科学的概念。预计该研究计划将通过在护理点诊断中的应用而产生更广泛的社会影响。开发更敏感、更定量和更低成本的健康监测平台将对医疗保健产生深远的全球影响。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Optical materials that can be tuned and adjusted in real time have become important in many applications. These include display technology, compact imaging devices, biomedical sensors, and point-of-care diagnostic tools. Liquids have many properties that would be beneficial for tunable optics. Liquids are deformable, have a broad range of adjustable properties, and have ultra-smooth surfaces with variable curvature. These characteristics could be particularly beneficial in tunable micro-lenses. In this project, the investigators will examine how complex droplets behave as tunable optical materials. Here, the complex droplets will be composed of two or three immiscible oils within an aqueous outer phase. A combination of experiments and analytical and computational modeling will be used. The aim is to provide a comprehensive understanding of the opportunities for realizing novel fluid-based optical technologies.Micron-scale optical elements have contributed significantly to the miniaturization of devices and instrumentation. They have been used in integral imaging and 3D displays, spatial light modulators, endoscopes, plenoptic cameras, and solar concentrators. Dynamically switchable reflective micro-optics, based on digital micro-mirror displays and continuously reconfigurable absorptive pixel technology enabled by liquid crystal displays, have enabled transformative advances in optical technology. Similarly, dynamic refractive micro-optics are poised to complement and extend the capabilities of present micro-optical devices. Although not yet a staple in the optical engineer's toolbox, liquids offer tremendous flexibility, design advantages, miniaturization promise, and manufacturing benefits in applications that require tunability. Despite the promise of using liquids within optical devices, the same malleability and sensitivity to many stimuli that make liquids so valuable for tunable optics can also make them difficult to control with the precision required for optical applications. A deeper fundamental understanding of strategies for liquid interface manipulation to fine-tune a fluid optical element and new approaches for controlling fluid-fluid interfaces within complex multiphase systems are critical for the advancement of optofluidic devices. In this collaborative effort, researchers aim to demonstrate that careful design of the composition and morphology of multiphase emulsion droplets provides a powerful strategy to form tunable lenses and micro-scale total internal reflection modules. This research pushes the boundaries of current liquid optics by exploring how droplets containing multiple reconfigurable fluid interfaces can be used to control lensing, correct for optical aberrations, and enable efficient spectral dispersion through total internal reflection. Understanding how liquid interfaces can be addressed independently or in tandem to dynamically tune the optical behavior of complex droplets will enable applications of fluids as optical components. Through this collaboration, the team aims to bring together optical theory with an enhanced understanding of how to manipulate multiphase liquids with the goal of broadening the role that complex fluids play in the realm of dynamic optical materials. Given the ease by which the complex droplets used in this proposal can be fabricated and reconfigured, the researchers will use fluid optical materials as a teaching tool to introduce K-12 students and educators to concepts in surface science. Broader societal impact of the research program is expected through applications in point-of-care diagnostics. Development of more sensitive, quantitative, and low cost platforms for health monitoring will have far-reaching global impact on healthcare.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.