摘要
具有远场超分辨聚焦特性、消色差、小尺寸和易加工的光学聚焦器件在光学成像、光学显微和光刻等领域具有巨大应用潜力.本文提出了一种基于光学超振荡基本原理,结合角谱衍射理论和二进制粒子群算法的二值振幅型远场超分辨消色差聚焦器件设计方法.为了验证所提出设计方法,首先针对波长λ1=405 nm,λ2=532 nm和λ3=632.8 nm的径向偏振光对二值振幅型远场超分辨聚焦器件振幅进行优化设计,再对三者振幅分布进行逻辑"与"操作,使其同时含有3个工作波长远场超分辨聚焦的振幅分布信息.仿真结果表明:在3个波长入射条件下相应的峰值半高全宽分别为0.441λ1(0.179 μm),0.469λ2(0.249 μm)和0.427λ3(0.270 μm),低于阿贝衍射极限,实现了远场超分辨消色差聚焦,且同时聚焦较小的旁瓣比率(＜15％).此类器件具有易加工、消色差和超分辨等优点,适用于光学系统微型化、集成化.所提出的设计方法可拓展至其他光学波段,并为相关光学研究领域提供核心聚焦器件.
Abstract
The far-field super-resolution focusing devices possess characteristics such as super-resolution focusing,achromatic,small size and easy machining,which make them highly promising in optical imaging,optical microscopy and lithography.In this work,we propose a binary-amplitude modulation-based method for generating far-field super-resolution achromatic focusing.By using the principles of optical super-oscillation,combined with angular spectral diffraction theory and binary particle swarm optimization(BPSO),we optimize the binary amplitude-type far-field super-resolution focusing devices,which have an identical radius of 100λ but different focal lengths:λ1=405 nm,λ2=532 nm and λ3=632.8 nm,respectively.Additionally,an achromatic metalens is integrated by using Boolean AND operation.To assess the feasibility of our proposed approach,numerical simulations are conducted via COMSOL Multiphysics employing FEM analysis.The simulation results demonstrate that the generated spots are located at 25.105λ,25.106λ,and 25.105λ,respectively.The corresponding full width at half maximum(FWHM)values are 0.441λ1(0.179 μm),0.469λ2(0.249 μm)and 0.427λ3(0.270 μm),which are smaller than the Abbe diffraction limit,and the far-field super-resolution achromatic focusing is realized.The sidelobe ratios are at low levels,i.e.12.5％,12.6％,and 14.2％.The binary amplitude-type far-field super-resolution achromatic devices have the advantages of easy machining,achromatism and super-resolution,and are suitable for miniaturization and integration of optical systems.
基金项目
国家自然科学基金(62105271)
四川省科技厅科技支撑计划(2020YJ0160)
西安近代化工研究所开放基金(SYJJ20210411)
西南科技大学博士基金(19zx7160)
维普
万方数据