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191.
The problem of computing light scattering by cylindrical fibers with high aspect ratio in the framework of the Null‐Field method with discrete sources is treated. Numerical experiments for investigating the scattering properties of two fiber geometries are performed using distributed spherical vector wave functions as discrete sources. 相似文献
192.
谢家麟 庄杰佳 黄永章 张令翊 林绍波 赵春农 李立华 吴钢 王钢 李承泽 傅恩生 苏憬 钟元元 王言山 李永贵 应润杰 杨学平 李有猛 韩斌 吴庆武 张玉珍 潘卫民 王建伟 张黎文 郭康柱 畅祥云 李亚南 戴立盛 徐金强 陆辉华 汪伯嗣 任廉重 田瑞生 《中国物理 C》1994,18(8):763-768
北京自由电子激光(BFEL)装置于1993年底在10.68μm处实现了饱和振荡.输出激光能量为3mJ,饱和平顶宽度2μs.对应饱和振荡平均功率为210kW(宏脉冲),峰值功率约为20MW,比自发辐射高8个量级,单程小讯号净增益为24%,转换效率为0.45%,与理论预期结果相符.光束质量接近衍射极限.目前装置可工作于9-11μm. 相似文献
193.
本文得到了沿一线性介质与非线性介质界面传输的TM波精确的色散关系和传播常数的解析计算公式,导出了计算非线性介质中传输功率流的积分公式。本文方法计算传播常数及功率流的优点是可不必先知道电场分布。 相似文献
194.
Yoshio Umezawa 《化学:亚洲杂志》2006,1(3):304-312
Lately, scientists have explored approaches to developing fluorescent and/or bioluminescent indicators to pinpoint cellular processes in single living cells. These analytical methods have become a key technology for visualizing and detecting what was otherwise unseen in live cells. The target signaling included second messengers, protein phosphorylations, protein–protein interactions, and protein localizations. 相似文献
195.
R.A. Gunasekaran M. Agarwal A. Singh P. Dubasi P. Coane K. Varahramyan 《Optics and Lasers in Engineering》2005,43(6):1086
A novel small fluid controlled optical lens system that is capable of displaying dynamic variation of its focal length and field-of-view (FOV) is designed and fabricated. In this active lens system, appropriate volume of the optical fluid can be pumped into or out of the lens chamber to provide double-convex (DCX) or double-concave (DCV) lens effect. Simple optical imaging experiments were performed using different sets of glass lenses with fixed focal lengths to determine the optimum lens configuration required for designing a dynamic optical lens system. The experimental results obtained from the glass lenses demonstrate that a combination of a single DCX lens with three DCV lenses provides a wider FOV. The flexible membranes for fluid controlled lenses were fabricated using polydimethylsiloxane polymer material, which has good optical transparency and elasticity. A simple fluid injection system is used to vary the radius of curvature of the lenses, and thereby to change the focal length. A dynamic optical lens system with a combination of one DCX and multiple variable focal length DCV lenses as designed here can image an object with a wide range of focal length and FOV. With this fluid controlled optical system, the FOV and focal length could be continuously varied and a maximum FOV of 118.3° could be achieved. The smallest f-number (f/#) for this fluid controlled single lens system was found to be 1.3, which corresponds to the numerical aperture value of 0.35. 相似文献
196.
197.
本文在Skyr}e相互作用、核物质近似和自洽半经典方法的基础上,将微观光学势的自洽研究推J“到中能区(60-r300MeV),研究了”+907r在该能区光学势的径向形状和温度效应 相似文献
198.
J.-Q. Shen H.-Y. Zhu P. Chen 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2003,23(2):305-313
There exist a number of typical and interesting systems and/or models, which possess three-generator Lie-algebraic structure,
in atomic physics, quantum optics, nuclear physics and laser physics. The well-known fact that all simple 3-generator algebras
are either isomorphic to the algebra sl (2, C) or to one of its real forms enables us to treat these time-dependent quantum systems in a unified way. By making use of
both the Lewis-Riesenfeld invariant theory and the invariant-related unitary transformation formulation, the present paper
obtains exact solutions of the time-dependent Schr?dinger equations governing various three-generator Lie-algebraic quantum
systems. For some quantum systems whose time-dependent Hamiltonians have no quasialgebraic structures, it is shown that the exact solutions can also be obtained by working in a
sub-Hilbert-space corresponding to a particular eigenvalue of the conserved generator (i.e., the time-independent invariant that commutes with the time-dependent Hamiltonian). The topological property of geometric phase factors and its adiabatic limit in time-dependent systems is briefly
discussed.
Received 6 July 2002 / Received in final form 21 October 2002 Published online 11 February 2003 相似文献
199.
Low-threshold, high-efficiency, high-repetition-rate optical parametric generator based on periodically poled LiNbO3
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We report a high-repetition-rate optical parametric generator (OPG) with a periodically poled lithium niobate (PPLN) crystal pumped by an acousto-optically Q-switched CW-diode-end-pumped Nd:YVO_4 laser. For the maximum 1064nm pump power of 970mW, the maximum conversion efficiency is 32.9% under the conditions of 250℃, 1064nm pulse repetition rate of 22.6kHz and pulse width of 12ns, and the PPLN OPG threshold in the collinear case is less than 23.7μJ. The output power increases with the increase of the crystal temperature. The 1485-1553nm signal wave and 3383-3754nm idler wave are obtained by changing the temperature and the angle of the PPLN crystal. 相似文献
200.
分析非晶硅薄膜晶体管在a-SiTFT-LCD中的开关特性,讨论这种开关结构中的主要功能膜材料尺寸与性能参量、光刻制备工艺,存储电容以及栅脉冲延迟效应等对a-SiTFT-LCD的通断电流比,信号响应与保持特性,图像亮度与对比度等光学特性的影响。 相似文献