超宽带折线圆极化器的优化设计

本文利用折线栅的等效电纳对多层折线圆极化器进行等效，根据其等效网络，采用罚函数当和变尺度法对四层板折线圆极化器进行优化设计，得出了不同频率范围内极化器的结构尺寸，并计算了相应的轴比，计算机模拟结果表明，在２－１８ＧＨｚ，频率范围内，所７设计的圆极化器轴比低于１ｄＢ，具有较好的实用价值。     

宽频偏光棱镜的视场角与设计

本文通过分析偏光棱镜视场角在宽频使用情况下变化关系，提出了从紫外至近红外光频区内偏光棱镜视场角的几种设计方法。     

一种高功率波导圆极化器的设计方法

介绍了一种高功率波导圆极化器的设计及调试方法。它采用渐变型波导,具有结构简单、易于加工及安装的优点。理论分析和实测结果比较吻合.现已用于某工程中。     

Glan－Taylor偏光棱镜的设计

本文介绍的Ｇｌａｎ－Ｔａｙｌｏｒ棱镜是一种重要的Ｇｌａｎ型冰洲石偏光棱镜，广泛用于各种光学系统中。本文从半视场角与棱镜切割角的关系入手，分析了影响Ｇｌａｎ－Ｔａｙｌｏｒ棱镜结构的若干参量，并介绍了一种棱镜设计方法，可以对用于任一波段起偏的这种棱镜实现结构的优化设计。     

Direct imprinting on a polycarbonate substrate with a compressed air press for polarizer applications

In this study, simple two-step processes were used to fabricate the wire-grid polarizer (WGP) on a polycarbonate (PC) sheet. The PC gratings were fabricated by direct imprinting of the PC sheet onto a silicon mold with a compressed air press (CAP). No additional imprinted polymer was required in the imprinting step. The applied pressure of 5 bar was much lower than the pressure reported in the literature, which was due to the use of the CAP. The WGP was further fabricated with an oblique aluminum (Al) sputtering on the PC grating. The rigorous coupled-wave analysis (RCWA) was performed to explain and verify the experimental results. The fabricated WGP should have potential application in the infrared region.     

射电天文X波段极化网络一体化设计与研究

射电天文望远镜中极化网络一般由极化器、波导同轴转换器、耦合器等几部分组成,为了获取最高限度的系统灵敏度,极化网络在射电天文低温接收机中会置于低温真空杜瓦20 K 温区,使其对接收机噪声温度的贡献降到最低。通过对极化网络的深入研究设计了一种基于隔板结构的X 波段极化器、耦合器和波导同轴转换器一体化结构。该设计既实现了极化器的线圆转换功能又实现了-30 dB 噪声耦合。测试结果表明该设计拥有良好的轴比、耦合度和驻波特性。同时一体化设计进一步减小了无源器件之间的级联,使低温低噪声放大器之前的馈源网络插入损耗进一步降低,提升了射电望远镜的接收灵敏度。     

基于部分保偏器件的干涉型光纤传感器

在单模光纤构成的干涉型光纤传感器中,存在偏振衰落问题,将导致干涉效率降低.而为了消偏振衰落采用全保偏器件的光纤传感器成本过于高昂,影响其实用性.以马赫.泽德干涉仪为基础,用反馈信号控制偏振控制器加起偏器的结构消除了偏振衰落,构造了基于部分保偏器件的干涉型光纤传感器.实验得到系统输出信噪比稳定在60 dB左右.     

基于偏振消光的全光纤衰减器

提出了一种基于偏振消光原理的新型连续可调全光纤衰减器,用琼斯矩阵方法分析了保偏光纤偏振器组合的衰减器的衰减原理,模拟分析了偏振器的消光比对衰减器的动态范围的影响.实验证明用分辨率为5 000 step/rotation的伺服电机和两个消光比为30 dB的保偏光纤偏振器组成的衰减器能获得27 dB的衰减动态范围、0.126%的光强分辨率和0.5 dB的损耗,并具有结构简单、可靠性高、稳定性好、不改变光束特性等特点.该器件已经在惯性约束核聚变(ICF)的时间脉冲整形系统中获得应用.     

Optics of sheared liquid‐crystal polarizer based on aqueous dispersion of dichroic‐dye nano‐aggregates

Abstract— The initial results on the optical properties of lyotropic liquid crystals under shear and following the cessation of flow are presented in the paper. Disk‐shaped aromatic molecules that self‐assemble into columnar nano‐stacks in the water form the supramolecule — the basic structural element of these liquid crystals. The nature of the flow is an important factor determining the material microstructure, providing a global order and initial conditions for the drying process. The dried coating exhibits the properties of an E‐type broadband polarizer. Understanding the dynamics of texture evolution and its interaction with the flow is of crucial importance to any development of polarizers coated with the liquid crystals.     

TFT LCD中常用的材料及其工作原理

TFT LCD是平板显示器的一种。本文介绍了TFT LCD常用的材料及其工作原理。