登录

双语推荐:柱矢量光束

本文提出了一种基于Metasurface产生任意柱矢量光束的方法.采用的Metasurface是在熔融石英上刻蚀空间变化的非周期光栅构成.非周期光栅会形成空变的有效双折射,从而对光场的偏振态空间分布进行调制.通过琼斯矩阵的方法分析得出这样的Metasurface可以将入射线偏振光转换为柱矢量光束,并且只需要改变入射线偏振光的偏振方向即可获得高阶庞加莱球赤道上任意一点的柱矢量光束.最后,用Metasurface搭建了一套简单、高效的柱矢量光束产生系统,实验结果与理论分析一致.
A method of generating cylindrical vector beams based on metasurface is presented in this paper. The metasurface is a fused silica with a space-variant non-periodic grating which is written by laser. The non-periodic grating induces a space-variant effective birefringence that modulates the space distribution of polarization state. It is shown that an incident linearly polarized light can be converted to a cylindrical vector beam by the method of Jones matrix. We can obtain an arbitrary cylindrical vector beam on the equator of the higher-order Poincaré sphere. A simple and efficient experimental system is established with a metasurface. Experimental results are in agreement with the theoretical analysis.

[ 可能符合您检索需要的词汇 ]

本文从理论和实验上系统研究了利用半波片实现高阶邦加球上柱矢量光束变换的方法.通过琼斯矩阵的方法理论分析得出变换前后柱矢量光束在高阶邦加球上两个对应点的纬度相反,经度随半波片的光轴方向角的不同而改变.最后,基于空间光调制器搭建了一套柱矢量光束产生及其变换系统,实验结果证明了这种方法的可行性.
A conversion approach for cylindrical vector beams on the high-order Poincaré sphere based on half-wave plate is studied theoretically and experimentally in this paper. The theoretical analysis using the Jones matrix method shows that the latitudes of two corresponding points produced by the cylindrical vector beams on the high-order Poincaré sphere before and after conversion are situated oppositely, and the longitudes are changed with different azimuth angles of the half-wave plate. Finally, an experimental system for the generation and conversion of the cylindrical vector beams is established with the spatial light modulator, and the experimental results demonstrate the feasibility of this approach.

[ 可能符合您检索需要的词汇 ]

为了求解坐标系下非傍轴矢量波动方程,得到光束的电场解析表达式,基于轴对称情况下沿角向偏振的电场,将非傍轴近似情况下的矢量波动方程进行了抛物线坐标的转化,利用分离变量法进行了相应求解,并给出了相应的数值计算。结果表明,非傍轴近似情况下,矢量波动方程的解能描述一种光束的电场,该场的解析表达式与合流超几何函数以及梅杰函数的解有关;光束的光强分布与第1类零阶贝塞尔模式光束类似;光束在近光轴处的光强表现为无限大并且沿边缘方向急剧衰减;在焦平面上沿着径向方向光强急剧减小。所得结果对于探究非傍轴近似情况下矢量光束的传输特性有一定的意义。
In order to solve the nonparaxial vector wave equation in the cylindrical coordinates and obtain electric field expression of the beams , based on the electric field along the azimuthal polarization under the axisymmetric circumstance , the vector wave equation under the nonparaxiality similar circumstances was transformed to the parabolic coordinates and was solved appropriately with the separation variables method .The corresponding numerical calculation was made .The results show that the new analytical solution of the nonparaxial vector wave equation is discussed to describe the propagation of a laser beam.The electric field of such a beam is found to be based on the solutions of the confluent hypergeometric function and the Meijer functions .The intensity distribution of beam is similar to the first-class zero-order Bessel beam mode.The intensity of the light beam near the optical axis is nearly infinite , and decays rapidly along the peripheral direction and decreases sharply alo
柱矢量光束具有对称性的偏振分布,其独特的光场分布和聚焦特性被广泛应用于光学微操纵及光学成像等领域,并迅速向亚波长尺度拓展。通常,亚波长尺度聚焦采用等离激元透镜实现,但存在光场调控的偏振态局限性。而借助光子晶体的负折射效应,不仅能够实现亚波长聚焦或成像,而且应对正交偏振态同时有效。采用对电磁波具有更强调控能力的一维金属光子晶体结构,计算得到的能带结构和等频曲线表明其负折射效应在特定波段对正交偏振态同时有效。在此基础上设计出一维金属光子晶体对称平凹镜结构,通过有限元算法模拟显示了可见光波段的径向和旋向偏振光的同时亚波长聚焦行为。进一步的结果表明,改变柱矢量光束的偏振组分能够直接有效地调节焦场空间分布及偏振分布特性。所提出的平凹镜结构能够实现对任意偏振组分的柱矢量光束的亚波长尺度聚焦,且该结构的设计对于各波段情况均有参考意义。该研究结果对小尺度粒子的光学微操纵、超分辨率成像等相关领域具有潜在的应用价值。
Cylindrical vector beams (CVB) can exhibit a unique optical field distribution and focusing characteristic, due to the cylindrical symmetry in polarization. They are widely used in optical micro-manipulation, super-resolution imaging etc. and can be extended to subwavelength scale applications rapidly. Usually, the focusing CVB in subwavelength dimensions is realized by using plasmonic lens. However, this method is restricted by the state of polarization of electromagnetic waves. Nevertheless, when the negative refraction effect of photonic crystals is utilized, subwavelength focusing or imaging can be achieved in orthogonal states of polarization simultaneously. In this paper, the one-dimensional metallic photonic crystal (1D-MPC) with stronger manipulation ability is discussed. The calculated band structure and equi-frequency surfaces show negative refraction for both orthogonal states of polarization in a specific wavelength band. A cylindrical 1D-MPC plano-concave lens is

[ 可能符合您检索需要的词汇 ]

采用矢量角谱的方法分析了Airy-Gaussian光束矢量结构,运用静态相位法得出了光束远场矢量结构的解析表达式.根据得到的TE项和TM项的解析表达式,分别研究了TE项和TM项及整个光束的能流分布.更好地阐明了Airy-Gaussian光束的物理图像,从而为操控光束提供潜在的新方法.
Based on the vector angular spectrum of the electromagnetic beam and the method of stationary phase, the analytical vectorial structure of the Airy-Gaussian beam in the far field has been presented. According to the analytical electromagnetic representations of the TE and TM terms, the energy flux distributions of the TE term, the TM term, and the whole beam in the far field are investigated respectively. The formulas obtained are applicable not only in the paraxial case, but also in the nonparaxial case. The physical pictures of Airy-Gaussian beams are well illustrated from the vectorial structure, which may provide a new approach to manipulate laser beams.

[ 可能符合您检索需要的词汇 ]

提出了利用π相位板产生矢量空心光束的新方案,两个偏振方向互相垂直的线偏振光波分别通过π相位板调制后进行强度叠加,得到椭圆空心光束,用矩形光阑调节相位板的几何尺寸,可以实时调节椭圆的离心率;调节π相位板的方位,能够实现径向矢量空心光束到角向矢量空心光束的转换。分析、讨论了方案的可行性和在原子光学中的潜在应用,结果表明:本方案在原子光学中有很好的应用前景。
A new scheme for generating a vector hollow beam is proposed by usingπphase plates, in which two linearly polarized light beams with perpendicular polarizations pass through twoπphase plates respectively, and then an elliptical hollow beam is generated by the superposition of two diffracted waves. The eccentricity of the ellipse can be adjusted by varying the geometric size of phase plates with rectangular diaphragm. And the conversion from the radial vector beam into the angular vector beam can be realized by adjusting directions of phase plates. The feasibility and potential applications in atom optics are analysed and discussed showing that our scheme has a good potential application in atom optics.

[ 可能符合您检索需要的词汇 ]

提出了一种组合非球面反射型太阳能聚光镜并给出了设计方法。聚光镜由38片非球面组成,每一片非球面都由一组特定系数C,a2,a4,a6,a8,a10的偶次非球面方程决定,是此特定非球面的一部分。根据非球面方程和光反射定律矢量形式,导出了非球面内壁上太阳反射光束的方向矢量与非球面系数C,a2,a4,a6,a8,a10的关系,适当地选择这些非球面系数,即适当地调整非球面面型,可以使太阳反射光束具有特定的方向矢量,使入射到非球面内壁上的太阳光束反射后全部聚焦在某一特定的区域内,形成小的光斑。每组特定系数都用粒子群优化算法求得,并经计算机模拟和实验证明其聚焦效果。聚光镜的光束压缩比为330∶1,其聚焦光斑可作为一种高温热源,而此聚光镜可以用在太阳能加热装置中。
In this paper , a build-up aspherical solar concentrating mirror and its design method are presented . It is composed of 38 pieces of revolution surfaces , and each piece of revolution surface is the part of the as-pheric surface defined by a set of specific coefficients C,a2 ,a4 ,a6 ,a8 ,a10 .According to the even aspherical e-quation and the law of reflection in vector form , the relationship between the direction vectors of rays of light reflected from the inner wall of aspheric surface and the coefficients of an aspherical equation , C,a2 ,a4 ,a6 , a8 ,a10 , has been derived .By appropriately choosing these aspherical coefficients , namely, appropriately ad-justing an aspherical surface type , the reflected light beam can have specific direction vectors , which can make the sunbeams incident on an aspherical inner wall focus on a particular area and form a small spot .Each group of specific coefficients is obtained by using particle swarm optimization algorithm .The focus

[ 可能符合您检索需要的词汇 ]

由于光楔在高精度微孔加工中起着对激光光束引导作用,为了提高激光微细孔加工质量,给出了一种提高光楔对激光微加工精度分析的方法。首先提出了单光楔矢量等效概念,基于单光楔矢量定义对双光楔矢量模型进行了建立与分析,并得出了多个光楔进行矢量叠加的新方法;其次,应用Matlab编写了仿真软件,仿真得出了激光束经过两个相同光楔后的轨迹,并指出了由于运动系统的不同步对激光微孔加工中打孔质量的影响,进行了误差定量分析并给出了误差计算公式。文中结论对高精度激光微孔加工控制系统设计时的性能指标提供参考。
The optical wedge plays a guiding and key role on the processing of high-precision micro-hole drilling by laser pulses. In order to improve the laser micro-hole processing quality, a method was presented to improve the analysis on the impact of the optical wedge on accuracy of laser micro-manufacturing. First the concept of the equivalent of a single wedge vector was proposed. The double wedge vector model was established and analyzed based on the definition of a single wedge vector, and the new method of the vector superposition of the multiple wedges was came up with. Secondly, the simulation software was programmed by using Matlab. The simulation results show the trail of the laser pulses through the double optical wedge. The effect of the quality of the micro-hole caused by the un-synchronization of the motion system is investigated. The deviation quantitative analysis is carried and the formula of calculation the deviation is given. The conclusion is of great value to the performa

[ 可能符合您检索需要的词汇 ]

利用瑞利—索末菲矢量衍射公式导出偏振光波矩孔矢量夫琅禾费衍射的解析计算式,通过模拟实验研究了椭圆偏振光的一般孔和亚波长孔的矢量夫琅禾费衍射情形,可应用于偏振光波偏振度检测和偏振成像等方面,表明所得计算式的有效性和可靠性,可在微光学、近场光学、衍射成像、光束传输变换以及光信息处理等方面发挥作用。
The analytic calculation formula of the vector Fraunhofer diffraction of polarized light wave through-out rectangular aperture is derived with Rayleigh-Sommerfeld vector diffraction formula. Then Fraunhofer vector dif-fraction of elliptically polarized light throughout general aperture or sub-wavelength aperture cases are studied with simulation experiments, these can be used for the detection of the polarization degree of polarized light and polariza-tion imaging, etc. the vector diffraction and the diffraction situation of general aperture and sub-wavelength aperture is discussed. The simulations show that the calculation formula is valid and reliable, it can play a role in micro-op-tics, near-field optics, diffraction imaging, light beam transmission and transformation, and light information process-ing and so on.

[ 可能符合您检索需要的词汇 ]

在相干反斯托克斯拉曼散射(coherent anti-Stokes Raman scattering, CARS)显微镜中,共线传输的紧聚焦高斯光束激发具有不同形状和尺寸的待测样品所产生的CARS信号场的空间分布决定了整体系统的结构特点。建立了紧聚焦条件下球形样品产生CARS信号场的理论模型。利用矢量波动方程分析了紧聚焦条件下线偏振的高斯光束的光场强度和相位分布。利用格林函数求解该模型中CARS信号场的矢量波动方程,模拟计算得到了不同直径球形样品的远场CARS信号场的空间分布。理论分析和模拟计算结果表明,对于小体积的球形样品,前向和背向传输的CARS信号场强度接近,因此采用大数值孔径物镜背向探测方式即可获得高对比度图像。对于大体积球形样品, CARS 信号场的强度大幅增强,且发射方向主要集中在前向的一定立体角内。因此,采用小数值孔径物镜即可有效收集前向传输的CARS信号。
In a coherent anti-Stokes Raman scattering (CARS) microscope, when samples with different shapes and dimensions are excitated by collinearly introduced and tightly focused Gaussian beams, the microscopic structure will be determined by the spatial distributions of generated CARS signals. Therefore, we build a theoretical model for CARS signals from spherical sample under the tightly focused condition. The intensity and phase distributions of tightly focused linear polarization Gaussian beams are analyzed with vector wave equations. The vector wave equation of CARS signals is derived from Green’s function. The far-field CARS radiation patterns of spherical scatters with different diameters are simulatively calculated. Theoretical analysis and simulative calculation results show that the intensities of forward and backward CARS signals from the small spherical sampler are similar. The images with high contrast can be obtained by backward detection method from an objective with