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1.
利用二波耦合实验研究了C60掺杂垂直排列向列相液晶(5CB)中全息光栅衍射信号的脉冲现象,实验发现没有相干光预照与有相干光预照的样品的衍射信号表现出不同的脉冲现象。折射率光栅瞬间增强产生的脉冲要比折射率光栅瞬间减弱时产生的脉冲显著得多。为了解释实验中观察到的这种现象,给出了液晶分子取向力矩平衡方程。  相似文献   

2.
偏振光下向列相液晶(5CB:C60)取向光折变特性的研究   总被引:1,自引:1,他引:0  
通过实验研究了外加电场对C60掺杂的向列相液晶(5CB)的取向光折变特性及水平和竖直偏振光对样品二波耦合和自相位调制现象的影响。通过测量样品的增益系数和光束耦合率可以看出,在水平偏振光照射下两束透射光有较强的能量转移而在垂直偏振光照射时几乎观察不到明显的能量耦合现象。可见,液晶盒中的分子取向与光束的偏振方向有很强的依赖关系。  相似文献   

3.
通过实验研究了C60掺杂的向列相液晶(5CB)在低光强下的自相位调制现象。样品经过二波耦合实验之后液晶分子进行一定的取向,这时在水平和竖直偏振光的照射下可观察到明显的自相位调制现象。改变入射光的偏振方向可以看到自相位调制的衍射图样也随之改变,原因就是液晶折射率变化的各向异性。可见,液晶盒中的分子取向与光束的偏振方向有很强的依赖关系。  相似文献   

4.
0306983用最佳偏振角泵浦光提高晶体中两波耦合增益[刊]/刘宏利//光电子·激光.—2002,13(11).—1135~1137(C) 摩擦强度对取向膜表面液晶取向度的影响[刊]/乌日娜//液晶与显示.—2002,17(6).—450~454(C)利用红外二向色性吸收实验,定量分析了不同摩擦强度的取向处理后取向膜表面的流晶分子取向度。实验结果表明,取向膜表面的液晶分子取向度随摩擦  相似文献   

5.
基于单片机设计了一套紫外线波长选择、定时控制和光强测量系统,用于研究紫外线照射下维生素D含量提升的试验。系统包括控制装置和测量装置,控制装置采用STC12C5A60S2单片机驱动液晶触摸屏完成人机交互操作,以继电器控制不同波长的紫外线灯管工作,实现控制波长和照射时间。测量装置采用UVM-30A紫外线传感器模块,利用STC12C5A60S2单片机采集传感器输出信号,将测量结果以紫外线光强指数显示在LCD1602液晶屏上,实现紫外线光照强度测量功能。系统有效地解决了紫外线照射蘑菇试验中对紫外线波长、光强测量以及照射时间控制的问题。实验测试表明该系统具有良好的稳定性和实用性,可广泛推广。  相似文献   

6.
利用Z扫描技术,分别测量了五种C60聚氨酯胺薄膜(C60含量分别为0%、0.16%、0.30%、0.42%、0.52%,厚度均为0.3mm)的非线性光学吸收系数和折射系数,并研究了该薄膜的光限幅特性。实验表明:随着样品中C60的含量由0增加到0.52%,薄膜的透射率可由70%逐渐减小到10%,且透射光功率可限制在25mJ/cm^2以下。薄膜的透射率或透射功率可以随C60含量不同而改变,即薄膜的光限幅性能可以通过调节C60含量的方式加以控制。最后,基于C60分子的五能级模型,采用激发态吸收(反饱和吸收)物理机理解释了薄膜的非线性光学特性及光限幅性能。  相似文献   

7.
向列相液晶中手性剂的含量对TN显示模式的显示效果起着至关重要的作用。通过对两种不同体系的液晶中加入不同含量的手性剂进行实验测定得出:添加手性剂对液晶分子的排列取向有序具有一定的作用;手性剂的含量不同,液晶的阈值电压也有所不同,手性剂含量增多则阈值电压增大,液晶的陡度值增大;手性剂含量不同,面板中的对比度有所不同,手性剂含量增多则对比度下降。通过从微观角度对液晶分子在面板中的排列状态进行理论分析,对以上实验结果的成因机理进行了解释,手性剂的合理添加能更好地使液晶与面板IC驱动相匹配,达到更高的对比度,改善液晶面板中出现的碎亮点显示不良,使液晶面板显示画面更鲜明、细腻、逼真。  相似文献   

8.
宽温型(SCL)液晶的剖析   总被引:4,自引:4,他引:0  
用(EI、CI)GC-MS,GC-IR多种分析技术对国外某公司宽温型(SCL:液晶相温度范围宽)液晶混合物组份进行了剖析,通过实验已全部确定了该混合物液晶里的16种成份,并用GC-MS的总离子流色谱图色面积归一法确定了其含量。  相似文献   

9.
液晶折射率与电压关系的研究   总被引:5,自引:0,他引:5  
液晶的一个重要特性是:液晶的折射率会随所加于液晶上的电压的变化而变化。本文正是对这一规律进行了研究实验,并得出了实验结果。  相似文献   

10.
聚合物分散液晶膜中液晶分子的电场取向效应   总被引:3,自引:2,他引:3  
制备了液晶微滴在聚合物基体中呈独立分散且具有不同尺度的PDLC复合膜,利用偏光显微镜实时地观察了微滴内液晶织构在适度电场作用下的变化特性,获得了有关微滴内液晶分子的动态取向信息。实验发现,当施加的电压由饱合值降低时,不同尺度的微滴内液晶分子呈不同的电场取向效应,对直径大于十几微米的微滴,液晶分子易呈现较强的取向滞后效应,而直径在微米量级的液滴其液晶分子的电场取向滞后效应相对减少。微滴内液晶分子的这种取向滞后效应正是PDLC膜在宏观上呈现光透过率滞后现象的反映。从作用能的角度出发,讨论了影响微滴内液晶分子取向滞后效应的因素,如微滴与基体的界面作用、液晶微滴的形状、电容效应以及工作温度等。  相似文献   

11.
DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.  相似文献   

12.
From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.  相似文献   

13.
The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.  相似文献   

14.
The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.  相似文献   

15.
Today, micro-system technology and the development of new MEMS (Micro-Electro-Mechanical Systems) are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.  相似文献   

16.
This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel's.  相似文献   

17.
A new quantum protocol to teleport an arbitrary unknown N-qubit entangled state from a sender to a fixed receiver under M controllers(M < N) is proposed. The quantum resources required are M non-maximally entangled Greenberger-Home-Zeilinger (GHZ) state and N-M non-maximally entangled Einstein-Podolsky-Rosen (EPR) pairs. The sender performs N generalized Bell-state measurements on the 2N particles. Controllers take M single-particle measurement along x-axis, and the receiver needs to introduce one auxiliary two-level particle to extract quantum information probabilistically with the fidelity unit if controllers cooperate with it.  相似文献   

18.
A continuous-wave (CW) 457 nm blue laser operating at the power of 4.2 W is demonstrated by using a fiber coupled laser diode module pumped Nd: YVO4 and using LBO as the intra-cavity SHG crystal With the optimization of laser cavity and crystal parameters, the laser operates at a very high efficiency. When the pumping power is about 31 W, the output at 457nm reaches 4.2 W, and the optical to optical conversion efficiency is about 13.5% accordingly. The stability of the out putpower is better than 1.2% for 8 h continuously working.  相似文献   

19.
Call for Papers     
正Wireless Body-area Networks The last decade has witnessed the convergence of three giant worlds:electronics,computer science and telecommunications.The next decade should follow this convergence in most of our activities with the generalization of sensor networks.In particular with the progress in medicine,people live longer and the aging of population will push the development of wireless personal networks  相似文献   

20.
正Information Centric Networking Information-Centric Networking(ICN) is an emerging direction in Future Internet architecture research,gaining significant tractions among academia and industry.Aiming to replace the conventional host-to-host communication model by a data-centric model,ICN treats data content as the first  相似文献   

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