Reda Francesco, Salvatore Marcella, Borbone Fabio, Maddalena Pasqualino, Ambrosio Antonio, Oscurato Stefano Luigi
Opt Express. 2022 Apr 11;30(8):12695-12711. doi: 10.1364/OE.455520.
Flat optical elements enable the realization of ultra-thin devices able to either reproduce or overcome the functionalities of standard bulky components. The fabrication of these elements involves the structuration of material surfaces on the light wavelength scale, whose geometry has to be carefully designed to achieve the desired optical functionality. In addition to the limits imposed by lithographic design-performance compromises, their optical behavior cannot be accurately tuned afterward, making them difficult to integrate in dynamic optical systems. Here we show the realization of fully reconfigurable flat varifocal diffractive lens, which can be in-place realized, erased and reshaped directly on the surface of an azopolymer film by an all-optical holographic process. Integrating the lens in the same optical system used as standard refractive microscope, results in a hybrid microscope capable of multi-depth object imaging. Our approach demonstrates that reshapable flat optics can be a valid choice to integrate, or even substitute, modern optical systems for advanced functionalities.
平面光学元件能够实现超薄设备，这些设备能够重现或超越标准大型组件的功能。这些元件的制造涉及在光波长尺度上对材料表面进行结构化处理，其几何形状必须经过精心设计以实现所需的光学功能。除了光刻设计性能折衷所带来的限制外，它们的光学行为之后无法精确调整，这使得它们难以集成到动态光学系统中。在此，我们展示了完全可重构的平面变焦衍射透镜的实现，该透镜可以通过全光学全息过程在偶氮聚合物薄膜表面直接原位实现、擦除和重塑。将该透镜集成到用作标准折射显微镜的同一光学系统中，可得到能够进行多深度物体成像的混合显微镜。我们的方法表明，可重塑的平面光学器件可以成为集成甚至替代具有先进功能的现代光学系统的有效选择。
