Optomechanical limits of tubular optofluidics

本课题的目的是研究全液体光流成像系统的光学性能极限。主要的光学性能考虑是像差控制和驱动速度。在项目结束时，我们打算展示像差校正流体成像系统，该系统可以以与经典的大块光学机械组件竞争的速度驱动。管状光流体技术是基于对许多液体的控制操作，具有精确定义的折射率，密度和不混溶性，包装在一个完全充满流体的圆柱形管中。相位前沿（半月板）的驱动是通过电润湿，由施加在管内表面的结构箔上的电压控制。在高空间频率波前调制中，增强像差控制和更精确地操纵液相前沿的关键是实现高电极密度。将对系统的流体静力学进行详细分析，并对液/液和液/表面界面进行详细设计。通过64个方位分布电极的实现，确定了相位前高空间频率定义的限制。此外，流体成像和扫描系统的高速驱动将需要新型的液体和介质界面材料，以优化电压和电场分布并降低驱动时间常数。通过对全液体成像系统的流体静力学和流体动力学分析，期望得到适合各种应用的驱动速度。作为高性能全液体成像和扫描系统的演示，可调变形成像仪；360度光学扫描仪，没有机械运动部件；实现了一种像差校正可调透镜系统。我们期望这些结果将产生足够的科学和技术影响，使光流体元件和系统在实际应用中变得更加接近可用性。

The objective of the current project is to research the optical performance limits of all-liquid optofluidic imaging systems. The primary optical performance considerations are aberration control and actuation speed. At the conclusion of the project, we intend to demonstrate aberration-corrected fluidic imaging systems which can be actuated at speeds which make them competitive with classical, bulk opto-mechanical components.The tubular optofluidic technology is based on controlled manipulation of numerous liquids, with precisely defined refractive indices, densities and immiscibility, packaged in a completely fluid-filled cylindrical tube. Actuation of the phase fronts (menisci) is through electrowetting, controlled by applied voltages on a structured foil on the inside surface of the tube.Key to enhanced aberration control and a more precise manipulation of the liquid phase fronts for high-spatial-frequency wavefront modulation is realization of a high electrode density inside this fluidic tube. Detailed analysis of the hydrostatics of the system will be undertaken, as will a detailed design of the liquid/liquid and liquid/surface interfaces. Through realization of 64 azimuthally-distributed electrodes, the limits to high-spatial-frequency definition of the phase fronts will be determined.In addition, high-speed actuation of fluidic imaging and scanning systems will require new and novel liquid and dielectric interface materials, to optimize voltage and electric field distributions and reduce actuation time constants. Through hydrostatic and hydrodynamic analysis of the all-liquid imaging systems, it is expected that actuation speeds suitable for a wide variety of applications will result.As demonstrators for high-performance all-liquid imaging and scanning systems, a tunable anamorphic imager; a 360-degree optical scanner with no mechanically-moving parts; and an aberration-corrected tunable lens system will be realized.We expect that these results will make sufficient scientific and technological impact so that optofluidic components and systems will become significantly closer to usability in real-world applications.