紫外三元复合消色差相位延迟器优化设计的分析

为了设计在紫外波段消色差性能优良的三元复合λ／4波片,根据复合波片理论,利用同一波长（300nm）的2个λ0／4波片和1个λ0／2波片组合成复合波片,研究了复合波片的相位延迟量随波长的变化,得出复合波片在250-350nm的光谱范围内是消色差的;在此基础上对三元复合消色差λ／4波片进行了优化设计,即通过改变中间波片的相位延迟量和精确调整复合角,使消色差范围拓宽到200-400nm,相位延迟计算偏差在5％左右．通过改变中间波片的材料,即氟化镁晶体代替石英晶体,用上述同样方法设计出UVC波段消色差λ／4波片,其相位延迟计算偏差在2％以内．这种优化设计对拓宽紫外波段消色差范围,提高延迟量精度具有实用价值．     

440nm-665nm消色差二分之一波片的二元设计

为了设计适用于可见光波段的消色差二分之一波片,根据复合波片理论,选用石英和氟化镁材料利用最小二乘拟合法,设计出了440 nm～665 nm范围的消色差λ/2复合波片。理论研究和实验检测结果均表明,依据此方案设计的消色差λ/2复合波片相位延迟精度可达λ/50,满足实际使用的需求。     

消色差复合延迟片

让在某一波长的1/4波片和1/2波片的两快轴的夹角为60°,组成复合1/4波片,则该复合片在该波长附近是消色差的;类似地,也得到了消色差1/2波片,并被实验所证实。     

全光纤的级联光纤系统琼斯弥勒矩阵测量

基于系统估值理论, 提出并实现采用光纤波片的光纤系统琼斯弥勒矩阵测量. 光纤波片和光纤系统有良好的适配性, 且简单易行. 针对光纤波片的环境敏感性, 提出并实现基于系统方程矩阵自相似特点的波片延迟校准方法. 此外, 还通过系统优化, 实现光纤波片旋转角度的调整. 经实验验证, 光纤波片延迟的校准和旋转角度的调整使系统误差得到了明显改善. 最后, 测量了1 520~1 620 nm波长范围内两段级联光纤的偏振参数及其弥勒矩阵谱.     

双λ／2相位延迟片的复合效应

基于现有复合波片研究的基础上,利用琼斯矩阵给出了由2个λ/2相位延迟片的组合理论.通过自行搭建偏光参数自动测量系统,测量了复合波片各种复合状态下的光强连续变化曲线,由此验证了复合波片组合理论的正确性.     

全内反射消色差相位延迟器的设计新方案

通过对高精度消色差相位延迟器理论设计的再研究,分别得到在不同中心折射率下和不同延迟精度下,延迟量随折射率改变的变化曲线.并设计出一种以632.8nm为中心波长的高精度相位延迟器,经实验验证,其消色差精度在±0.05°范围内的波长区域约为:350.0.nm-1200 nm.     

菱体型消色差相位延迟器的光谱特性分析

从全内反射相变方程出发,以菲涅尔菱体为例,分析了消色差相位延迟器的相位延迟量随折射率变化的光谱特性,结果表明：在所设计的中心波长处,延迟器件不仅仅局限于选择低色散的材料,色散较大的高折射率材料制作的延迟器件也可以具有良好的消色差性,且较大的全内反射角有利于改善延迟器件的消色差性. 从而为优化菱体型相位延迟器的消色差性,扩大材料的选取范围提供理论指导.     

基于亚波长光栅消色差相位延迟器的研究

通过对亚波长光栅相位特性的研究,基于严格耦合波理论和遗传算法,设计了一种应用在光通信波段(1350~1750nm)范围内的亚波长光栅宽光谱消色差1/4相位延迟器,相位延迟量控制在90°±2°,衍射效率在80%以上。并对该光栅结构的工艺容差进行了分析,分析结果表明,所设计的光栅结构相位延迟量在合理范围内,符合工业生产相位延迟器的要求。     

二元复合波片退偏器的理论分析

根据理想退偏器的米勒矩阵形式,分析讨论了不同组合的复合波片的米勒矩阵．得出了以下结论：让两波片以不同的角速度绕光线为轴旋转,当复合波片为一个1／4波片和一个1／2波片组合时,只要它们的角速度满足一定的比例时,可以组合成一个比较理想的退偏器;当复合波片为两个1／4波片组合或为两个1／2波片组合时无论怎样旋转都不能组合成理想退偏效．这些理论结果对复合波片退偏器的设计具有好的参考价值．     

Fresnel菱体型消色差延迟器的研究

为了提高Fresnel菱体延迟器的消色差性能,通过对各个参数进行分析,得出了结构角α的关系式。结果表明,设计的延迟器件在550nm-1240nm的光谱范围内最大延迟误差小于1°,这一结果对设计λ/4消色差廷迟器是非常有帮助的。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with     

Journal of Donghua University ( English Edition) Contents of Volume 31

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