【摘 要】
：
We study the high numerical aperture focusing properties and typical applications of axially-symmetric polarized beams (ASPBs) with high polarization orders. We calculate the field distribution near focus of an aplanatic system for incident ASPBs with dif
【机 构】
：
StateKeyLaboratoryofPrecisionMeasurementTechnologyandInstruments,TsinghuaUniversity,Beijing100084,Ch
【出 处】
：
ChineseOpticsLetters
论文部分内容阅读
We study the high numerical aperture focusing properties and typical applications of axially-symmetric polarized beams (ASPBs) with high polarization orders. We calculate the field distribution near focus of an aplanatic system for incident ASPBs with different polarization orders and initial azimuthal angles, and based on the simulation results, we find some unique focusing properties of the beams, such as ever on-axis energy null, strong longitudinal field, and flowerlike intensity distribution at focus. In addition, we can manipulate the three-dimensional (3D) focused field distribution flexibly by use of diffractive optical elements (DOEs), which will give rise to some interesting applications, and we also discuss possible applications and present an example of a 3D optical chain at last.
其他文献
用氩离子激光泵浦的连续波染料激光选择性激发钠原子,观察到钠原子3s-5s态的双光子跃迁。激发波长为6022.3埃(相当于3s-5s态跃迁频率的一半)。可调谐染料激光在选定的波长范围内输出功率低于1毫瓦,带宽为0.5埃。
Laser induced damage threshold (LIDT) testing is the effective methods to research the lifetime of optical elements. According to ISO 11254 standards, a LIDT testing system of ArF excimer laser is established. The laser beam size on the sample surface can
The liquid-core fiber with relatively high refractive index difference between the core and cladding is proven to be bending insensitive. The single mode condition and bending loss of the fiber with a mixture of toluene and chloroform as its core material
Dissipative solitons emerge as stable pulse solutions of nonintegrable and nonconservative nonlinear physical systems, owing to a balance of nonlinearity, dispersion, and loss/gain. A considerable research effort has been dedicated to characterizing ampli
使用了氦气中的7次谐波转换，从266.1亳微米的激光脉冲产生38.0亳微米的相干光。叙述了5次和7次谐波信号随氦气压的变化。
基于激光诱导炽光(LII)法和光腔衰荡光谱(CRDS)技术,搭建了用于研究火焰碳烟颗粒的测量平台,并对其性能参数进行了表征。碳烟颗粒路径积分衰减系数测量结果表明,双色LII测试系统和CRDS系统相互独立。同时运行双色LII和CRDS系统,测量得到的路径积分衰减系数随着火焰高度的增加先增大后减小,两个系统的测量结果具有较好的相关性。通过优化拟合模型及去除系统噪音,获得了较好的光腔衰荡信号拟合结果。
Measurement of light distribution in biological tissue contributes to selecting strategy and optimizing dose for biomedical application. In this letter, a photoacoustic method combined with Monte Carlo simulation was used to estimate the three-dimensional
提出了一种基于双弹光差频调制的中红外相位延迟精确测量方法。通过两个硒化锌型弹光调制器(PEM)的差频降低系统调制频率,产生载有被测相位延迟的低频调制信号,调制后的1倍差频幅值和2倍差频幅值相除可求得被测波片的相位延迟。该方法可有效抑制光强波动及PEM相位延迟波动对测量的影响,提高测量精度。对测量原理进行了理论推导,设计了硒化锌型PEM和实验系统。实验结果表明,相位延迟测量误差不大于0.004%,灵敏度可达5×10
-4 rad。
泊松算法在重建时物体边缘容易产生未封闭的曲面,最终建成的物体存在表面粗糙、孔洞等问题。基于此,提出一种改进的三维点云重建算法。该方法首先用统计滤波器对点云简化去噪,消除重建表面的锯齿状现象;然后建立点云间拓扑结构,对点云法向量进行法向重定向,以减少法向指向的二义性;最后将具有磁盘拓扑结构的点云映射到平面,将二维三角剖分方法应用于平面参数化,给二维点提供三角形连通性,并将其传输回三维点云形成网格曲面