Hybrid Aspherical Liquid-Tunable Optical Systems

与在软件和电子方面取得的巨大进步形成对比的是，光学系统的设计和实施基本上遵循传统方法，主要是由于对传统光学元件的持续依赖。Halos Long Term Vision是通过提供一种系统的方法来设计和制造能够有效控制像差的复杂光学部件而不诉诸复杂的多元素设计来改变光学系统设计。具体地说，Halo的目标是开发一种由集成静电致动器驱动的新型液体可调、消色差和非球面透镜，并通过创新的成像系统展示其多功能性。与需要许多透镜来控制像差的传统成像系统相比，Halo系统将包括一个可调透镜和一个图像传感器。这种单透镜将具有可调非球面折射面和衍射面，以分别控制大焦距范围内的球差和色差。通过将这种新型组件与最先进的图像处理技术相结合，Halo旨在开发一种从系统设计和实际实施方面都适用的成像技术，从而最大限度地发挥其潜在影响。HALLOS的成功将取决于以下科技成就的支柱：-设计球面和色差无像差可调谐透镜的可靠方法。-开发与可调谐透镜单片集成的片上致动器-用于单片晶圆级制造的稳健和高成品率制造工艺-具有通过焦距调谐进行实时数值场曲率校正的单透镜成像系统。在HALO中，我们的目标是开发一种新的可调谐透镜设计方法，以解决所有这些问题，采用一种由最先进的微制造技术实现的集成方法。这一选择遵循了在实际使用的设备中实现上述创新的目标。内窥镜成像和先进的消费电子成像系统被认为是Halo透镜的主要焦点。通过将尽可能多的硬件复杂性转化为高效的计算方法，Halo的目标是用一个镜头获得最先进的成像性能。由于场曲率校正是现代成像系统这种复杂性的最主要来源，我们将利用光晕透镜独特的无像差焦距调节能力，在曝光过程中动态调整焦平面，以便记录在不同径向位置具有最佳焦距的单独图像。这些图像的数字组合将提供没有场曲率的图像。围绕可调谐透镜设计的成像系统概念将作为演示，展示这种组件将为光学系统设计带来的多功能性。

In contrast to the immense progress made in software and electronics, optical system design and implementation essentially follows the traditional methods, predominantly due the ongoing reliance on conventional optical components. HALOs long term vision is to transform optical system design by providing a systematic method to design and manufacture sophisticated optical components capable of effective aberration control without resorting to complex multi-element designs. Specifically, HALO aims to develop a novel liquid-tunable, achromatic and aspherical lens driven by an integrated electrostatic actuator and demonstrate its versatility through an innovative imaging system. Compared to conventional imaging systems that require numerous lenses to control aberrations, the HALO system will comprise a single tunable lens and an image sensor. This single lens will feature a tunable aspherical refractive surface and a diffractive surface in order to control spherical and chromatic aberrations over a large focal length range, respectively. By combining this novel component with state-of-the-art image processing techniques, HALO aims to develop a versatile imaging technology both in terms of system design and its practical implementation, such that its potential impact is maximized. HALOs success will rest on the following pillars of scientific and technical achievements:– A reliable method to design spherical and chromatic aberration-free tunable lenses.– Development of an on-chip actuator monolithically integrated with the tunable-lens – A robust and high-yield fabrication process for monolithic wafer-level manufacturing– A single-lens imaging system with real-time numerical field-curvature correction through focal length tuningIn HALO, we aim to develop a new approach to tunable lens design to address all these issues following an integrated approach, enabled by state-of-the-art microfabrication techniques. This choice follows the objective of realizing the above-listed innovations in a device of real practical use. Endoscopic imaging and advanced imaging systems for consumer electronics are envisioned to be primary focus of the HALO lens. By transferring as much hardware complexity as possible into efficient computational methods, HALO aims to attain state-of-the-art imaging performance with a single lens. Since field curvature correction is the foremost source of such complexity for modern imaging systems, we will exploit the unique aberration-free focal length tuning capability of the HALO lens to dynamically adapt the focal plane during exposure, such that separate images with optimum focus at different radial positions are recorded. A digital combination of these images will provide an image without field-curvature. The imaging system concept to be designed around the tunable lens will act as a demonstrator, showcasing the versatility that such a component would bring into optical system design.