Hybrid Aspherical Liquid-Tunable Optical Systems
Optics, Quantum Optics and Physics of Atoms, Molecules and Plasmas
Polymer Materials
Final Report Abstract
In contrast to the remarkable advances in software and electronics, the field of optical system design and implementation has largely stuck to traditional methodologies. This is largely due to the continued reliance on conventional optical elements. The HALO project was conceived with the aim of developing a novel approach to the fabrication and design of hybrid tunable optical components. These components would have the novel ability to effectively manage aberrations without the need for complex multi-element configurations. Central to HALO’s objective was the development of an inventive liquid-tunable lens that embodied both achromatic and aspheric properties. This lens would be driven by an integrated actuator, demonstrating its adaptability within an innovative imaging framework. Unlike conventional imaging setups that rely on an array of lenses to mitigate aberrations, the HALO system sought to offer an alternative to this approach. It aimed to achieve aberration control through a single tunable lens coupled to an image sensor. Through the synergy of this breakthrough component and cutting-edge image processing methods, HALO envisioned the creation of a versatile imaging technology that balanced simplicity with high optical performance. As of the submission date of this report, the main technical results of the project can be summarized as follows: • Development of a new liquid tunable aspherical lens concept with integrated electromagnetic actuator • A new hybrid liquid-tunable aspherical lens concept featuring a diffractive optical element for chromatic aberration correction over the entire visible range • A novel lens fabrication process based on polymer molding • A prototype design of a three-lens camera objective featuring the hybrid liquid-tunable aspherical lens. We have performed extensive modeling work to analyze various actuation schemes, and identified electromagnetic actuation as the most suitable approach for the project. In addition to its large force density, EM actuators also easier to manufacture, with the disadvantage of larger size, compared to electro-active polymer actuation as envisioned in the proposal. To reduce the power consumption, we devised a novel mechanism, that allowed biasing the lens at its optimum operation point. We have also enhanced this lens design by an integrated DOE to substantially reduce chromatic aberration within the operation range of interest. The most time and resource consuming aspect of the project was the development of the manufacturing process, as we converged to a stable solution after many variants. The project is yet to produce any journal publications. There are however, two journal publications under development. Compared to its initial goals, the project can be considered as partially successful. We have made significant progress in all major research directions, and demonstrated the feasibility of the optical concepts conceived in the original project proposal. However, the target performance figures for the conceived devices are yet to be reached. There were two main challenges the impeded the project progress. The first major factor was personnel issues, which led to major delays. The second was technical, and concerns the reliability an yield of lens fabrication.
