平顶高斯光束经含失调圆孔光阑的失调光学系统的传输特性

为分析平顶高斯光束通过光学系统传输时圆孔光阑失调和光学元件失调对平顶高斯光束传输特性的影响,利用失调圆孔光阑的近似展开式和适用于失调光学系统的广义衍射公式,得出了平顶高斯光束经含失调圆孔光阑的失调光学系统传输的近似解析式,给出了输出光束场分布与光束参量、光阑孔径尺寸、光阑和光学元件失调量等的定量关系.针对特定光学系统定量分析了各失调量对输出光束场分布的影响,结果表明各元件失调都对输出光束强度分布产生较大影响.但在各失调量较小的情况下,透镜失调对输出光束传输特性的影响比光阑失调对输出光束传输特性的影响更明显.     

扩束准直光学系统中光学元件失调对高斯光束传输变换的影响分析

基于广义惠更斯-菲涅尔衍射积分公式, 以高斯光束为激光束模型,推导了激光光束通过失调扩束准直光学系统的传输公式,分析了光学元件失调对扩束准直光学系统输出光束传输特性的影响,并在此基础上进行了仿真。实验结果表明,高斯光束通过失调扩束准直光学系统时,出射光束变为偏心高斯光束,光学元件失调程度越大,输出光束越偏离光轴,光束质量越差。在同样的失调下,长焦距光学元件对输出光束影响更大,因此在激光扩束准直光学系统中,调整长焦距光学元件更为重要。     

平顶高斯光束经含失调圆孔光阑的失调光学系统的传输特性

为分析平顶高斯光束通过光学系统传输时圆孔光阑失调和光学元件失调对平顶高斯光束传输特性的影响,利用失调圆孔光阑的近似展开式和适用于失调光学系统的广义衍射公式,得出了平顶高斯光束经含失调圆孔光阑的失调光学系统传输的近似解析式,给出了输出光束场分布与光束参量、光阑孔径尺寸、光阑和光学元件失调量等的定量关系.针对特定光学系统定量分析了各失调量对输出光束场分布的影响,结果表明各元件失调都对输出光束强度分布产生较大影响.但在各失调量较小的情况下,透镜失调对输出光束传输特性的影响比光阑失调对输出光束传输特性的影响更明显.     

厄米-高斯光束通过正弦和矩形浮雕光栅传输特性的比较研究

使用严格的傅里叶模式理论和反射-透射系数矩阵递推算法(RTCM)，对不同阶数的厄米-高斯光束通过特征尺寸与波长可比拟的正弦和矩形浮雕光栅中的传输特性做了详细的研究和比较.结果表明，入射光束的初始场分布和浮雕光栅的结构影响浮雕光栅内的光强分布.矩形浮雕光栅对光束匀滑效果优于正弦形浮雕光栅.     

高功率激光装置中局部波前畸变的非线性传输

 根据高功率激光装置中强激光束传输的特点，建立了描述光束通过光学元件时引入的局部波前畸变模型，并利用纹波传输的线性化处理方法，研究了带有局部波前畸变的高强度光束的传输规律。以一个连续的非增益激光介质为例，用该模型进行数值模拟，给出了不同空间尺度的局部波前畸变的频谱分布、不同空间频率的纹波引起的振幅非线性增长曲线、不同B积分的非线性增益随光束传输距离的变化曲线,光束振幅非线性增益达到最大时光束的传输距离和标准传输距离不同时由局部波前畸变引入的振幅分布。研究表明为了防止光学元件损坏，应避免光学元件表面出现半径为0.5~2.0 mm的局部瑕疵。     

基于石英晶体天平和微纳光纤的有机污染物在线监测

为了监测高功率激光驱动器中有机污染物的挥发特性以及其在光学元件表面的沉积特性,研究了基于石英晶体微量天平和微纳光纤传感器的真空腔体内有机物在线监测技术.首先测试了不同分子态污染物浓度时石英晶体天平的响应性能,然后采用视角因子等分法对微纳光纤传感器和石英晶体天平进行对比实验,模拟有机污染物在光学表面沉积的特性.实验结果表明,石英晶体天平和微纳光纤测试有机物在光学表面沉积时响应一致,均可用于高功率激光驱动器有机污染物的在线监测;当污染物面密度大于0.5×10-5g/cm2时,微纳光纤传感器有较高精度和响应速度;有机污染物浓度越高,其更容易吸附沉积在光学元件表面.     

聚焦光在亚表面损伤介质中的散射特性

针对光学元件的亚表面缺陷,结合基于激光共焦层析的亚表层检测方法,建立聚焦光束在亚表面损伤介质中的传输模型,并采用有限元分析方法,仿真研究K9玻璃光学元件亚表层缺陷对聚焦光束的散射调制特性,特别对颗粒状和微裂纹两类特殊缺陷的光学调制特性进行研究和分析,探索了波长、缺陷大小、缺陷折射率及缺陷方向对聚焦光束散射特性的影响规律,通过分析包含亚表面损伤缺陷信息的光场分布图和强度变化曲线,获得了亚表面损伤缺陷的信息,并对其进行评价。     

光束控制系统组件化仿真及运动解耦方法研究

利用激光系统组件化仿真软件构建了光束控制系统的组件化仿真框架,对几何/波动光学传输、光束定向器机架与其内部光学元件的耦合运动进行了仿真,提出了目标脱靶量数据和传感器图像自动更新、光束定向器机架与其内部多块快速倾斜镜控制驱动量自动解耦的数值仿真新方法,并在动态跟踪控制可视化过程中完成了光束定向器机架、多块快速倾斜镜驱动控制以及光学传输成像的仿真,满足了光束控制系统建模仿真的普适性、灵活性、易用性设计目标。最后,大气传输校正联合仿真实例证明:利用精跟踪、自适应光学技术能有效抑制大气低频扰动幅值,校正高频扰动的影响。     

一维非均匀Kerr介质的传输矩阵算法

研究了一维非均匀Kerr介质的子层逆向递推传输矩阵算法,给出了数值实现方案.此方法可以方便而精确地模拟非均匀Kerr介质的传输行为.应用此算法模拟一维Kerr缺陷光子晶体的光学双稳开关过程时, 得出了和非线性时域有限差分方法相一致的结果.     

用于光束整形的衍射光学元件设计的混合算法

提出了一种用于衍射光学元件优化设计的混合遗传迭代爬山算法,该算法将迭代量化傅里叶变换算法融入到遗传算法中,然后在整体遗传算法结束后,对找到的当前最优解再用爬山法进行局部寻优,从而得到最优的衍射光学元件表面相位分布.用该混合方法设计了衍射光学元件,可以将入射的高斯光束整形成方形的均匀光斑.模拟结果表明:该混合算法具有收敛速度快、设计准确度高等优点.相比于其它设计方法,本文提出的方法能较好地改善整形效果,特别适用于光束整形的衍射元件设计.     

Propagation of partially polarized, partially coherent beams in uniaxial crystals orthogonal to the optical axis

The propagation of partially polarized and partially coherent beams in uniaxial crystals orthogonal to the optical axis is investigated. The analytical formulae for the elements of the cross-spectral density matrix of partially polarized and partially coherent beams propagating through uniaxial crystals orthogonal to the optical are derived. The numerical results show that the degree of polarization decreases with the increase of the ratio of extraordinary to ordinary refractive indices at a certain propagation distance, and the influence of uniaxial crystals on the degree of coherent is not so evident. And the beams spread more rapidly in the direction parallel to the optical axis than orthogonal to the optical axis in positive crystal with the propagation distance increasing.     

螺旋光束经过振幅型衍射光学元件的传输特性及其拓扑电荷数的测量

本文提出了一种利用空间光调制器生成杨氏双缝和三角孔等振幅型衍射光学元件的方法. 利用平面波角谱衍射公式和柯林斯公式研究了螺旋光束经过这两种衍射元件后的传输特性, 并利用杨氏双缝和三角孔实现了螺旋光束拓扑电荷数的测量. 由于空间光调制器可以方便和高精度地改变光学器件的几何尺寸和所在的空间位置, 因此可便捷地实现螺旋光束拓扑电荷数的测量.     

Transformation problem for radiation with radial polarization

The propagation and transportation of laser beams with radial polarization (RP beam), possessing a high efficiency in their interaction with matter, are studied. The effect of different elements of an optical system on the polarization state of RP beams is analyzed. It is shown that optical systems with radial symmetry do not disturb the polarization of an RP beam and that the negative effect of a mirror on the state of polarization can be counterbalanced.     

无衍射光束的特性和生成方法

介绍了无衍射光束的概念和传输性质，描述了应用常规的光学元件和计算机产生的全息图生成无衍射光束的方法及其潜在的应用价值。     

一种新空心光束的理论及实验研究

提出了一种用来描述空心光束的新理论模型——空心高斯光束模型，通过控制光束参数可以方便地调制空心光束黑斑的大小.导出了空心高斯光束经傍轴光学系统的解析传输变换公式.利用导出的公式计算分析了空心高斯光束在自由空间的传输特性.在实验上利用矩阵本征值方法设计了能输出空心高斯光束的光学谐振腔，对实验上得到的空心高斯光束进行了传输特性的研究.结果表明，理论和实验相吻合.该空心高斯光束产生的光势阱为控制冷原子提供了一条新途径. 关键词： 空心高斯光束 光学谐振腔 传输特性     

The connection of geometrical optics with the propagation of gaussian beams and the theory of optical resonators

The propagation of light near the axis of astigmatic optical systems may be described by the geometrical-optics approximation with the aid of ray-matrices. The application of the theory of diffraction to the propagation of light in such systems leads to integrals containing essentially the elements of the ray-matrices as parameters. The ABCD-law is derived by evaluating these integrals for gaussian beams. Integral equations applicable to astigmatic optical resonators, having nearly vanishing diffraction losses, are set up. They are only valid under certain conditions, which are comprehensively discussed. The eigensolutions and the eigenvalues of these integral equations are given. The spot-sizes at the resonator mirrors are derived from the eigensolutions, and the eigenvalues lead to the resonance condition. Spot-sizes and resonance condition appear as functions of the elements of the characteristic resonator matrices. The methods described here are applied to the propagation of gaussian beams through gas-lenses and to a resonator containing an internal gas-lens.     

M~2-factor of high-power laser beams through a multi-apertured ABCD optical system

Based on the generalized truncated second-order moments, an approximate analytical formula of the beam propagation factor M~2 of high-power laser beams passing through the optical system with multiple hard-edged apertures is deduced. Numerical examples of the beams passing through an aperture-spatial filter are enclosed, and the influences of amplitude modulations(AMs) and phase fluctuations(PFs) on the beam propagation quality of high-power laser beams passing through the multi-apertured ABCD optical system are considered and discussed. It is shown that PFs are able to degrade the beam propagation quality of laser beams more than AMs when the high-power laser beams passing through the aperture-spatial filter, furthermore, one or two aperture-lens optical systems configured appropriate aperture parameters are both able to upgrade the beam propagation quality of high-power laser beams. The M~2 factor of Gaussian beam passing through the multi-aperture optical system is a special case in this paper.     

Off-axial elliptical Hermite-cosh-Gaussian beams

A new kind of light beams named the off-axial elliptical Hermite-cosh-Gaussian beams (EHChGBs) is introduced in this paper by use of tensor method. An analytical propagation expression for an off-axial EHChGB passing through an axially nonsymmetrical optical ABCD system is derived by use of vector integration. The derived formula can be easily reduced to the propagation formulas of off-axial elliptical cosh-Gaussian beams and elliptical Hermite-cosh-Gaussian beams. Some numerical simulations are illustrated for the propagation properties of off-axial EHChGBs passing through a free space and a focusing optical system, and further extensions are suggested.     

Generalized Helmholtz-Gauss beam and its transformation by paraxial optical systems

We introduce the generalized Helmholtz-Gauss (gHzG) beam and analyze its propagation through optical systems described by ABCD matrices with real and complex elements. The transverse mathematical structure of the gHzG beam is form invariant under paraxial transformations and reduces to those of ordinary HzG and modified HzG beams as special cases. We derive a closed-form expression for the fractional Fourier transform of gHzG beams.     

基于纳米天线的多通道高强度定向表面等离子体波激发

设计了一种带有纳米天线的金属微腔结构, 以实现高强度表面等离子的定向激发. 在利用双狭缝结构实现表面等离子体波定向激发的基础上, 分别结合共振增强和干涉相长原理, 在传统结构的入射端面上添加纳米天线结构, 并增加狭缝通道数, 实现了定向激发的表面等离子体波的能量增强. 基于纳米天线的多通道高强度定向表面等离子体波激发装置结构简单, 系统紧凑, 并能够有效提高定向传播的表面等离子体波的能量密度和传播距离, 其对微纳光学传输和高密度光学集成领域等方面的研究具有重要意义.