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编码电磁超表面构成信息超材料研究领域的一个分支. 文中提出了基于编码电磁超表面的Bessel波束产生设计方法,为Bessel波束的产生与调控提供了新的解决方案;同时对基于电磁超表面的Bessel波束产生与设计的基本方法进行了梳理总结. 首先通过反射型编码电磁超表面分别设计了不同类型的Bessel波束,包括单波束零阶Bessel波束、双波束零阶Bessel波束、单波束高阶Bessel波束以及双波束高阶Bessel波束;然后对于每一种类型的Bessel波束分别对应给出了有关的设计理论和方法,并通过全波电磁仿真的方法进行了相应的仿真验证;最后,鉴于信息超材料技术的发展,基于编码电磁超表面的Bessel波束设计可以进一步地应用于信息超材料有关的系统设计,如近场无线信息/能量传输、近场雷达探测与成像,这也为信息超材料提供了一种可供选择的应用场景. 相似文献
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A new way for generating Bessel beams at mm and sub mm-wavelengths is presented in this paper, in which diffractive optical
elements (DOE’s) are designed for converting incident Gaussian beams into Bessel beams. In order to reduce the computational
burden and therefore improve the design efficiency, two measures are adopted in our design. One is a body-of-revolution finite-difference
time-domain (BOR-FDTD) method that uses a two-dimensional (2-D) solution space instead of a full 3-D space and thereby saves
tremendous computational resources, and that is utilized to calculate the fields diffracted by the DOE’s. The other is a microgenetic
algorithm (MGA) that has been proved to be more effective than the conventional GA, and that is employed for accelerative
optimization. The utility of the present design tool, which combines a MGA with a BOR-FDTD method, is demonstrated by three
examples. Numerical simulation results indicate that the designed DOE’s can not only flexibly generate zero- or higher- order
Bessel beams when compared with axicons, but also have higher diffraction efficiencies when compared with amplitude holograms.
An erratum to this article can be found at 相似文献
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用改进的模拟退火算法设计二元光学阵列器件 总被引:3,自引:2,他引:1
为提高收敛速率,本文对模拟退火(SA)算法进行改进,并用此改进算法设计用于产生大扇出系数、任意形状分布光阵列的二元光学器件,其衍射效率设计值达85%以上,输出阵列不均匀性小于3%。 相似文献
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非相干光源产生无衍射光束的实验中,入射光束的均匀性对产生无衍射光束的质量有很大影响。文中以非相干光源白光LED为例,通过对LED自身发光特性的分析,对光线传播过程进行数学建模,用非成像光学光通量守恒原理,对均匀照明设计方法进行理论推导,得到了一种基于非成像光学产生均匀光束的透镜设计方法。用三维建模软件进行建模并用光学仿真软件进行光线追迹,确定用该方法设计的透镜能满足实验对入射光束均匀度的要求,并初步实验获得较高质量的零阶无衍射Bessel光,验证了该设计方法的合理性。 相似文献
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涡旋光束经过轴棱锥后的聚焦特性 总被引:1,自引:0,他引:1
研究了涡旋光束通过轴棱锥聚焦后的聚焦特性。利用惠更斯-菲涅耳衍射积分理论推导了涡旋光束经过轴棱锥聚焦后所获得的聚焦光强分布。数值模拟结果表明,涡旋光束经过轴棱锥聚焦后可获得高阶贝塞尔光束。研究了不同锥角的轴棱锥对涡旋光束聚焦特性的影响以及不同拓扑电荷数对聚焦特性的影响。结果表明,在轴棱锥对应的最大准直距离内,所获得的高阶贝塞尔光束保持了原有的无衍射特性。 相似文献
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介绍一种二元光学元件的设计方法。为了克服达曼光栅在二维设计上的局限性,采取均匀采样的矩形孔径编码方式进行优化设计。结果表明:与达曼光栅相比,不仅可将总衍射效率提高10 %以上,还可得到更多样的二维设计图样,只是输出点阵均匀度略低于达曼光栅。因此,在均匀度要求不太高的高强光束变换中,这种二值型位相光栅的设计方法对于设计二维衍射图样十分简便有效,且其计算结果易于加工制作,具有很高的应用价值。 相似文献
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A true Bessel beam is a family of diffraction-free beams. Thus the most interesting and attractive characteristic of such
beam is non-diffracting propagation. In optics, the comparisons of maximum propagation distance had been done between Bessel
and Gaussian beams by Durnin and Sprangle, respectively. However, the results obtained by them are conflict due to the difference
between their criteria. Because Bessel beams have many potential applications in millimeter wave bands, therefore, it is necessary
and significant that the comparison is carried out at these bands. A new contrast criterion at millimeter wavelengths is proposed
in our paper. Under this criterion, the numerical results are presented and a new conclusion is drawn. 相似文献
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G.S. Sokolovskii V.V. Dudelev S.N. Losev K.K. Soboleva A.G. Deryagin K.A. Fedorova V.I. Kuchinskii W. Sibbett E.U. Rafailov 《Progress in Quantum Electronics》2014
We report on recent progress in the generation of non-diffracting (Bessel) beams from semiconductor light sources including both edge-emitting and surface-emitting semiconductor lasers as well as light-emitting diodes (LEDs). Bessel beams at the power level of Watts with central lobe diameters of a few to tens of micrometers were achieved from compact and highly efficient lasers. The practicality of reducing the central lobe size of the Bessel beam generated with high-power broad-stripe semiconductor lasers and LEDs to a level unachievable by means of traditional focusing has been demonstrated. We also discuss an approach to exceed the limit of power density for the focusing of radiation with high beam propagation parameter M2. Finally, we consider the potential of the semiconductor lasers for applications in optical trapping/tweezing and the perspectives to replace their gas and solid-state laser counterparts for a range of implementations in optical manipulation towards lab-on-chip configurations. 相似文献
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Zhi Li Wenwei Liu Guangzhou Geng Zhancheng Li Junjie Li Hua Cheng Shuqi Chen Jianguo Tian 《Advanced functional materials》2020,30(23)
Metasurfaces and planar photonic nanostructures have drawn great interest from the optical scientific community due to their diverse abilities of manipulating electromagnetic waves and high integration. Most metasurfaces launch diffracting waves, and thus suffer from divergence, short working distance, and instability. Although much effort has been devoted to researching nondiffracting metasurfaces which can launch electromagnetic waves with constant transverse intensity profiles in free‐space propagation, the number of working channels is inherently limited as these meta‐devices are implemented in the linear optical regime. Here, the multiplexed nondiffracting nonlinear metasurfaces are theoretically proposed and experimentally realized, which can generate the representative nondiffracting Bessel beam and Airy beam. Three Bessel beams with different numerical apertures and topological charges and three Airy beams with different propagation curves and focal lengths can be generated by a combination of different spins and wavelengths. The complex properties of the nondiffracting beams can be designed and detected in a more comprehensive and concise way with Fourier analysis. This proof‐of‐concept represents a new strategy for realizing multiplexed nondiffracting metasurfaces with advantages of ultracompactness, high‐pixelation, and easy integration and paves the way for multi‐channel optical communication and manipulation. 相似文献
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贝塞尔光束通过环形硬边光阑的ABCD光学系统传输 总被引:1,自引:1,他引:0
通过把环形光阑函数展开为复高斯函数的方法,推导出贝塞尔光束通过有环形光阑限制的近轴ABCD光学系统的传输近似解析公式。通过数值计算,对贝塞尔光束通过环形光阑的传输特性进行了详细的研究,给出了光阑内、外半径等参数对光强分布的影响规律。 相似文献
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无衍射贝塞尔光束的实现方法 总被引:3,自引:0,他引:3
无衍射光束是一种新兴的光束,它具有很好的应用前景,本文给出了无射贝塞尔光束的理论背景、实现方法及相应实验结果,比较了这些方法的优缺点,提出了无衍射光束的应用范围。 相似文献
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大型ICF装置靶场传输光路排布研究 总被引:1,自引:0,他引:1
大型惯性约束聚变(ICF)装置靶场将从主放大系统输出的平行激光阵列转换为靶室附近的球形阵列,并以特定的角度进入终端光学系统。靶场传输光路排布作为靶场光传输系统总体结构设计的依据,在满足物理和光学等要求的基础上,还应重点考虑工程建设成本和系统维护性能。随着ICF装置规模的增大,打靶激光光束数量增加,靶场传输光路排布难度增加。结合目前国内外大型ICF装置,分析了靶场传输光路排布的特点,讨论了传输光路排布与光传输系统布局、光机结构设计和系统维护性能的关系,为我国更多束激光打靶的ICF装置的靶场传输光路排布提出建议。 相似文献