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1.
固-液结构平板掺杂声子晶体的滤波特性   总被引:1,自引:0,他引:1  
为了研究一维固-液结构平板掺杂声子晶体的滤波特性,利用一维固-液结构平板掺杂声子晶体中弹性波横向受限的条件,推导出弹性波在一维固-液结构平板掺杂声子晶体中各个模式满足的关系式。研究了弹性波各模式的缺陷模随模式量子数和杂质厚度的变化规律。这些结果可用于声子晶体滤波器的设计。  相似文献   

2.
一维微粗糙面与其上方金属平板的复合电磁散射研究   总被引:3,自引:0,他引:3  
研究了一维导体随机粗糙面与其上方金属平板的复合电磁散射。应用互易性原理使求解复合目标的二次散射场简化为求解包含平板上的极化电流和微粗糙面散射场的积分方程。利用物理光学近似和粗糙面微扰法分别计算了平板上的感应电流和粗糙面的电磁散射场,导出了复合散射模型单、双站散射的计算公式并给出了单站数值计算结果,讨论了后向复合散射截面随入射频率及平板尺寸、位置的变化关系。  相似文献   

3.
采用Cole-Hopf变换法,将平板光波导导模所满足的二阶常微分方程(Helmholtz方程)变换成一阶常微分方程(Riccati方程),用较简单且有效的方法分析导模的特性。给出了多层阶跃型及渐变型平板波导导模的精确解析解和数值解法及实例;给出了非线性平板波导传播特性的数值计算法及实例。  相似文献   

4.
无机电致发光(EL)平板显示是一项有着广泛应用前景的自发光型平板显示技术。本文简单介绍了无机EL平板显示器的结构、原理和实现全彩色显示的方法,阐述了所使用的电极、介质和发光材料的作用、要求及研究现状,分析了存在的问题,并展望了其产业化的前景。  相似文献   

5.
一种面向分布式网络管理的自适应可扩展模型   总被引:6,自引:2,他引:4  
王平  赵宏  李莉 《通信学报》2002,23(12):118-128
本文针对大规模分布式网络的特点,提出了一种灵活、动态、自适应伸展性网络管理方案。它采和层次型体系结构,支持多个管理域的分布式网络管理,适应了大规模网络的规模可变性和弹性的特点。为了解决网络事件大量性、多样性和相关性的问题,本文将网络事件分为简单事件和复合事件两种类型,采用层次型事件处理机制和基于动态时间窗的事件合成方法,保证了事件检测的可靠性,平衡了系统负载,降低了网络资源的占有率。  相似文献   

6.
金属包层渐变折射率平板波导传播特性   总被引:1,自引:0,他引:1  
本文采用多层线型分割近似,结合欧姆损耗微扰法,分析了金属包层渐变折射率平板波导的传播特性。按此方法计算了几类典型波导的传播常数数值,结果均与精确值相吻合,且物理概念清楚,计算方法简单。  相似文献   

7.
用激光测量平行平面透明介质折射率的一种方法张长君(大连大学师范学院,大连116024)本文概括地介绍了从单层到多层平行平面透明介质折射率的一种简单测量方法。1.单层平板透明介质。取一块平板透明介质,例如玻璃,把一块经水浸湿的白纸贴到玻璃上,让He—N...  相似文献   

8.
本文采用多层线型分割近似,结合欧姆损耗微扰法,分析了金属包层渐变折射率平板波导的传播特性,按此方法计算了几类典型波的传播常数数值,结果均与精确值相吻合,且物理概念清楚,计算方法简单。  相似文献   

9.
卢有祥 《光电技术》2005,46(4):11-15,24
本文介绍了一种新型的无汞平板放电灯。该灯使用无电极的介质阻挡层,在平板内充入Ne-xe(氖-氙)混合气体。在相对较低的气压下。产生等离子体,激发荧光粉发光。该灯结构简单,使用了一种特殊的电极结构,通过调整脉冲电压和波形,即可以获得均匀放电。当优化了气体浓度和驱动条件时。光效可达到100多流明/W;通过与基本元件的简单重复连接,可以制造出大尺寸的平板光源。  相似文献   

10.
平板扬声器产生于1998年,它使用由Neosonica开发的复合层压结构材料的声板和由NXT技术制成的振动板(表面声)来产生声音.而传统的扬声器是使用振膜或振盆来产生声音。因此平板扬声器比传统振盆的扬声器传送声音更远、更均匀,而且对声音的传送或重放所需的功率较低。平板扬声器还有响度均匀的优点,但缺点是低音不足。  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.
Waveguide multilayer optical card (WMOC) is a novel storage device of three-dimensional optical information. An advanced readout system fitting for the WMOC is introduced in this paper. The hardware mainly consists of the light source for reading, WMOC, motorized stages addressing unit, microscope imaging unit, CCD detecting unit and PC controlling & processing unit. The movement of the precision motorized stage is controlled by the computer through Visual Basic (VB) language in software. A control panel is also designed to get the layer address and the page address through which the position of the motorized stages can be changed. The WMOC readout system is easy to manage and the readout result is directly displayed on computer monitor.  相似文献   

17.
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   

18.
The collinearly phase-matching condition of terahertz-wave generation via difference frequency mixed in GaAs and InP is theoretically studied. In collinear phase-matching, the optimum phase-matching wave hands of these two crystals are calculated. The optimum phase-matching wave bands in GaAs and lnP are 0.95-1.38μm and 0.7-0.96μm respectively. The influence of the wavelength choice of the pump wave on the coherent length in THz-wave tuning is also discussed. The influence of the temperature alteration on the phase-matching and the temperature tuning properties in GaAs crystal are calculated and analyzed. It can serve for the following experiments as a theoretical evidence and a reference as well.  相似文献   

19.
Composition dependence of bulk and surface phonon-polaritons in ternary mixed crystals are studied in the framework of the modified random-element-isodisplacement model and the Bom-Huang approximation. The numerical results for Several Ⅱ - Ⅵ and Ⅲ- Ⅴ compound systems are performed, and the polariton frequencies as functions of the compositions for ternary mixed crystals AlxGa1-xAs, GaPxAS1-x, ZnSxSe1-x, GaAsxSb1-x, GaxIn1-xP, and ZnxCd1-xS as examples are given and discussed. The results show that the dependence of the energies of two branches of bulk phonon-polaritons which have phonon-like characteristics, and surface phonon-polaritons on the compositions of ternary mixed crystals are nonlinear and different from those of the corresponding binary systems.  相似文献   

20.
An insert layer structure organic electroluminescent device(OLED) based on a new luminescent material (Zn(salen)) is fabricated. The configuration of the device is ITO/CuPc/NPD/Zn(salen)/Liq/LiF/A1/CuPc/NPD/Zn(salen)/Liq/LiF/A1. Effective insert electrode layers comprising LiF(1nm)/Al(5 nm) are used as a single semitransparent mirror, and bilayer cathode LiF(1 nm)/A1(100 nm) is used as a reflecting mirror. The two mirrors form a Fabry-Perot microcavity and two emissive units. The maximum brightness and luminous efficiency reach 674 cd/m^2 and 2.652 cd/A, respectively, which are 2.1 and 3.7 times higher than the conventional device, respectively. The superior brightness and luminous efficiency over conventional single-unit devices are attributed to microcavity effect.  相似文献   

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