阮仁杰 1,2,3曹银花 1,2,3王晓帆 1,2,3马艳红 1,2,3[ ... ]兰天 1,2,3,*
1 北京工业大学 北京市激光应用技术工程技术研究中心， 北京 100124
2 北京工业大学 跨尺度激光成型制造技术教育部重点实验室， 北京 100124
3 北京工业大学 材料与制造学部 先进半导体光电技术研究所， 北京 100124
为解决现有点阵结构光投影装置中准直透镜会导致较强的零级衍射而造成投影点阵光强分布不均匀的问题，提出了一种基于底发射垂直腔面发射激光器的片上点阵光投影装置结构，并给出了衍射光学元件设计思路。首先对目标光场进行光强调整和坐标变换，在无准直透镜情况下利用基于瑞利-索末菲衍射积分的Gerchberg-Saxton改进算法获得片上衍射光学元件的相位分布，并最终对该点阵投影装置的投影效果进行评估。结果表明：在衍射光学元件设计过程中采用高斯光束作为光源时，该结构能更好地抑制零级衍射，获得光强分布更加均匀的投影点阵。此外，该结构不仅可省去透镜的安装，减小投影装置尺寸，还可通过流片工艺实现光源和衍射光学元件一体化集成。
衍射光学 片上结构光 瑞利-索末菲衍射积分 衍射光学元件 Gerchberg-Saxton算法 底发射VCSEL diffractive optics on-chip structured light Rayleigh-Sommerfeld diffraction integral diffractive optical element Gerchberg-Saxton algorithm bottom-emitting VCSEL 红外与激光工程
2022, 51(6): 20210640
Author Affiliations
Abstract
Centre for Micro-Photonics, Faculty of Engineering, Science and Technology, Swinburne University of Technology, John Street, Hawthorn, VIC 3122, Australia
Graphene oxide (GO) ultrathin flat lenses have provided a new and viable solution to achieve high resolution, high efficiency, ultra-light weight, integratable and flexible optical systems. Current GO lenses are designed based on the Fresnel diffraction model, which uses a paraxial approximation for low numerical aperture (NA) focusing process. Herein we develop a lens design method based on the Rayleigh-Sommerfeld (RS) diffraction theory that is able to unambiguously determine the radii of each ring without the optimization process for the first time. More importantly, the RS design method is able to accurately design GO lenses with arbitrary NA and focal length. Our design is experimentally confirmed by fabricating high NA GO lenses with both short and long focal lengths. Compared with the conventional Fresnel design methods, the differences in ring positions and the resulted focal length are up to 13.9% and 9.1%, respectively. Our method can be further applied to design high performance flat lenses of arbitrary materials given the NA and focal length requirements, including metasurfaces or other two-dimensional materials.
ultrathin flat lens graphene oxide Rayleigh-Sommerfeld diffraction Fresnel diffraction Opto-Electronic Advances
2018, 1(7): 180012
1 中国科学院重庆绿色智能技术研究院, 重庆 400714
2 中国科学院大学, 北京 100049
3 军械工程学院 电子与光学工程系, 石家庄 050003
提出了一种基于瑞利-索末菲衍射理论的设计方法, 用于近场大衍射角衍射光学元件的设计.研究在大衍射角条件下, 衍射光学元件面和输出面采样点之间应满足的空间位置关系.采用无远场和傍轴近似的正、逆向衍射计算方法对传统盖师贝格-撒克斯通算法进行改进, 得到近场大衍射角衍射光学元件的设计方法.以“田”字形目标光强为例, 将传统设计方法、现有大衍射角衍射光学元件设计方法和本文提出的设计方法进行对比, 结果表明: 在近场区域, 本文方法可以准确重构出大衍射角衍射光学元件的目标光场, 其他两种方法则会导致重构光场产生明显的畸变或者模糊化.
光学设计 衍射光学 衍射光学元件 瑞丽-索末菲积分 计算全息 相位恢复 迭代算法 Optical design Diffractive optics Diffractive optical element Rayleigh-Sommerfeld diffraction theory Computer holography Phase retrieval Iterative algorithm 光子学报
2017, 46(11): 1122003
Author Affiliations
Abstract
1 中国科学院上海光学精密机械研究所高功率激光物理联合实验室, 上海 201800
2 中国科学院大学, 北京 100049
Aiming at morphology of laser induced damage mitigation pit on the rear surface of 3ω silica optical component, the mitigated area and its downstream intensity distributions with different morphologies are simulated by finite-difference time-domain method (FDTD) and Rayleigh-Sommerfeld (R-S) diffraction integral method, respectively. The results show that when the angle between the tangent line of endpoints on the section contour of the pit and incident light is over 70°, the maximum intensity inside the mitigated optics is less than 1.66, and mitigation effect is better than that of other angles. The maximum downstream intensities of a pit in shape of parabolic surface, cone and truncated cone are all less than 1.46 with an angle of 70° and a width of 200 μm. But when the width of pit increases to 1 mm, for instance, the maximum downstream intensity is as high as 9.31 and area with high intensity covers a long range. Thus, taking the difficulty of laser machining technology into account, a conical pit with an angle larger than 70° is the first choice for the damage mitigation on the rear surface of silica optical component.
激光技术 激光损伤修复 时域有限差分法 瑞利索末菲衍射积分 laser technique laser induced damage mitigation finite-difference time-domain method Rayleigh-Sommerfeld diffraction integral Collection Of theses on high power laser and plasma physics
2016, 14(1): 0602009
1 华中科技大学 光学与电子信息学院, 武汉 430074
2 中国工程物理研究院 激光聚变研究中心, 绵阳 621900
为了提高传统球面镜腔3kW射频板条CO2激光器光束质量, 设计了新型抛物面镜负支非稳-波导混合腔; 结合标量光束的瑞利-索末菲衍射理论与特征向量法, 研究了大菲涅耳数下镜面类型对非稳波导混合腔光场传输特性的影响; 利用矩形波导理论、1维近似分析得出了波导传输损耗及偏振情况。结果表明, 将非稳方向输出镜和尾镜改为与光轴交点处曲率半径为R1=951.32mm和R2=1088.68mm的抛物镜面, 能够避免尾镜漏光, 可有效改善模式鉴别特性; 常用波导电极镀膜材料中, 镀铝电极内波导方向传输损耗最小, 传输光场为x偏振的EH1模。采用电极镀铝的抛物面非稳波导腔能够降低损耗、提升光束质量。
激光器 射频板条CO2激光器 非稳波导混合腔 抛物面镜 瑞利-索末菲衍射 大菲涅耳数 lasers radio frequency slab CO2 laser unstable-waveguide hybrid cavity parabolic mirror Rayleigh-Sommerfeld diffraction large Fresnel number
1 中国科学院上海光学精密机械研究所高功率激光物理联合实验室, 上海 201800
2 中国科学院大学, 北京 100049
针对三倍频光学元件后表面的损伤修复形貌，分别采用时域有限差分法（FDTD）和瑞利索末菲（R-S）衍射积分法，来模拟不同形貌下元件修复区域内以及其后续的光场分布。结果表明，当修复坑截面轮廓线端点切线与光束传播方向夹角大于70°时，元件内部光强极大值小于1.66，修复效果优于其他角度。夹角为70°、宽200 μm的抛物面型、圆锥型和圆台型凹坑的后续光强极大值小于1.46。但是当修复坑宽度较大如达到1 mm时，圆台型凹坑的后续光强极大值高达9.31，且作用区间长。因此，考虑实际激光修复工艺的难度，夹角大于70°的圆锥型凹坑是石英元件后表面损伤修复的首选形貌。
激光技术 激光损伤修复 时域有限差分法 瑞利索末菲衍射积分
Author Affiliations
Abstract
Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Science, Shanghai 201800, China
The physical meaning and essence of Fresnel numbers are discussed, and two definitions of these numbers for offaxis optical systems are proposed. The universal Fresnel number is found to be N=(a2/λz)*C1+C2. The Rayleigh–Sommerfeld nonparaxial diffraction formula states that a simple analytical formula for the nonparaxial intensity distribution after a circular aperture can be obtained. Theoretical derivations and numerical calculations reveal that the first correction factor C1 is equal to cosθ and the second factor C2 is a function of the incident wavefront and the shape of the diffractive aperture. Finally, some diffraction phenomena in off-axis optical systems are explained by the off-axis Fresnel number.
correction factor off-axis Fresnel number off-axis optical system Rayleigh–Sommerfeld diffraction integral Collection Of theses on high power laser and plasma physics
2014, 12(1): e17
Author Affiliations
Abstract
Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Science, Shanghai 201800, China
The physical meaning and essence of Fresnel numbers are discussed, and two definitions of these numbers for offaxis optical systems are proposed. The universal Fresnel number is found to be N=(a2/λz)*C1+C2. The Rayleigh–Sommerfeld nonparaxial diffraction formula states that a simple analytical formula for the nonparaxial intensity distribution after a circular aperture can be obtained. Theoretical derivations and numerical calculations reveal that the first correction factor C1 is equal to cosθ and the second factor C2 is a function of the incident wavefront and the shape of the diffractive aperture. Finally, some diffraction phenomena in off-axis optical systems are explained by the off-axis Fresnel number.
correction factor off-axis Fresnel number off-axis optical system Rayleigh–Sommerfeld diffraction integral High Power Laser Science and Engineering
2014, 2(3): e17
温州大学物理与电子信息工程学院, 浙江 温州 325035
用矢量Rayleigh-Sommerfeld(VRS)衍射理论分析计算了高数值孔径多台阶相幅型菲涅耳波带片(M-SHFZP)的聚焦场分布。当线性偏振光垂直入射到M-SHFZP，结果显示: 1) 由于薄膜透射率随着刻蚀台阶深度发生变化，致使实际的M-SHFZP 的聚焦强度小于多台阶纯相位型菲涅耳波带片(M-SPFZP)的聚焦强度，但是M-SHFZP 的聚焦光斑大小基本上与M-SPFZP 的相同；2) 聚焦光的强度随着台阶数的增加而增加，但聚焦光斑的大小不随台阶数变化；3) 对于低数值孔径的M-SHFZP，光轴上的强度呈现一个多焦点分布，但是对于高数值孔径的M-SHFZP，高级焦点的强度被大大抑制。台阶数愈多，数值孔径愈大，抑制高级次焦点的能力愈强。VRS 矢量衍射理论的计算结果与时域有限差分法(FDTD)模拟结果基本一致。
物理光学 聚焦 矢量Rayleigh-Sommerfeld 衍射理论 多台阶相幅型菲涅耳波带片 高数值孔径 激光与光电子学进展
2014, 51(6): 060501
1 中国科学院上海光学精密机械研究所， 上海 201800
2 zlj@siom.ac.cn
基于矢量瑞利索末菲衍射积分，建立了非傍轴条件下四瓣高斯光束经过偏心圆孔光阑在自由空间传输的矢量场模型。选取倾斜光轴作为参考光轴，借助于硬边圆孔的复高斯级数分解，得到了近场模型下衍射场分布的矢量解析式。通过数值计算和模拟，详细讨论了f参数、光束阶次、衍射孔位置和截断参数对像场分布的影响，包括衍射场主瓣强度的位置和光束宽度。这些结论有助于更好地理解四瓣高斯光束在离轴非对称光学系统中的传输特性。
物理光学 四瓣高斯光束 矢量瑞利索末菲衍射积分 硬边圆孔光阑
