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1.
如果在折射率较高的电介质基底上镀一层折射率较低的电介质薄膜(介质膜的另一侧为折射率更低的介质,如空气),并且恰当选择基底内光束的入射角,使得光束在基底-介质膜界面上折射到薄膜内、在薄膜-空气界面上全反射,那么反射光束的Goos-Ha¨nchen(GH)位移在一定条件下会得到共振增强。采用微波技术直接地测量了这种Goos-Ha¨nchen位移随电介质膜厚度的变化,测量结果与理论预言吻合得较好。  相似文献   

2.
电介质膜增强的Goos-H(a)nchen位移的微波测量   总被引:5,自引:1,他引:4  
如果在折射率较高的电介质基底上镀一层折射率较低的电介质薄膜(介质膜的另一侧为折射率更低的介质,如空气),并且恰当选择基底内光束的入射角,使得光束在基底-介质膜界面上折射到薄膜内、在薄膜-空气界面上全反射,那么反射光束的Goos-H(a)nchen(GH)位移在一定条件下会得到共振增强.采用微波技术直接地测量了这种Goos-H(a)nchen位移随电介质膜厚度的变化,测量结果与理论预言吻合得较好.  相似文献   

3.
基于古斯汉欣效应的皮米级位移传感器的实验研究   总被引:1,自引:0,他引:1  
本文利用光束在对称双面金属包覆波导表面反射时古斯一汉欣(Goos—Hanchen)位移具有极大的增强效应,提出一种灵敏度的极高的新型位移传感器。与传统的光强传感器相比,这种传感器消除了光源的能量波动对灵敏度的影响,从而能够观测更加微小的位移变化。在实验上实现了8pm微小位移传感。研究表明,该器件测量实时性强、精确度较高...  相似文献   

4.
提出一种基于液晶光阀(LCLV)和光束分析仪(LBP)直接测量Goos-Hänchen(GH)位移的新方法。在文中我们首先研究了LCLV对光偏振态调制的特性,结果发现,当控制电压发生变化时,光的偏振态也随之变化。然后利用LCLV对光偏振态的调制和LBP记录光斑的重心位置的变化,直接测量出TE和TM两种偏振态入射时棱镜单界面反射光束的GH位移差。这个探测方法简单,不需要复杂的外部处理电路,且实验结果与理论结果很吻合,这个方法也可以进一步直接测量二维位移。  相似文献   

5.
薄膜增强的Goos-H(a)nchen位移   总被引:1,自引:1,他引:1  
在单界面的全反射和双棱镜结构的受抑全内反射中,Goos-Hanchen(GH)位移量只能达到波长的量级,在实验中很难对其进行探测.在镀有薄膜的玻璃棱镜界面上,当入射角小于但接近于棱镜与薄膜(其折射率小于棱镜的折射率)界面的临界角时,全反射光束的GH位移共振增强现象.分析表明,在入射角给定的情况下,共振峰的峰值随着薄膜厚度的增加而增加,峰值位移量可以达到光波长的100~1000倍,且位移量可通过改变入射角和薄膜厚度来调节.最后给出了为使反射光束的轮廓不变,薄膜的厚度应满足的条件.  相似文献   

6.
在光谱椭偏测量中,玻璃基底的背反射会给测量结果造成较大影响。针对平板显示器件玻璃基底表面氮化硅镀膜进行了椭偏测量和模型计算。采用相干背反射模型“空气基底空气”计算并拟合得到与厂商数据符合较好的玻璃基底折射率。对氮化硅薄膜采用Tauc Lorentz色散模型进行了分析拟合,讨论了薄膜与基底界面层、表面粗糙度对光学常数及模型拟合的影响,表明在薄膜与基底间晶格失配的情况下,界面层的引入对改善拟合度是必要的。给出了薄膜体系的光学常数、薄膜结构的分析结果。  相似文献   

7.
为了降低高精密使用场合下多层介质高反射薄膜的表面散射,首先从多层介质薄膜双向反射分布函数(BRDF)出发,理论分析了双向反射分布函数与薄膜界面电场强度的关系。在入射光为正入射且中心波长632.8nm处的反射率大于99%的要求下,采用SiO2、Ta2O5两种材料设计了膜系G/(HL)8/A和膜系G/(HL)8 H/A,并分析了两种膜系界面的电场强度分布。然后以膜系G/(HL)8 H/A界面的电场分布为基础对场强进一步优化,得到了膜系G/(HL)60.4L1.6H1.5L0.5H/A。理论计算了正入射条件下三种膜系的双向反射分布函数,发现当散射角为-45°~45°时,膜系G/(HL)6 H0.4L1.6H1.5L0.5H/A表面的BRDF小于膜系G/(HL)8/A和膜系G/(HL)8 H/A。同时计算了三种膜系表面的总散射损耗(S),与膜系G/(HL)8/A和膜系G/(HL)8 H/A相比,优化膜系G/(HL)6 H0.4L1.6H1.5L0.5H/A的S降低了91.44%、37.98%。实验验证了利用膜层界面电场强度调控薄...  相似文献   

8.
潘永强  陈佳 《红外与激光工程》2016,45(1):118007-0118007(5)
为了降低光学薄膜的表面散射损耗,依据微粗糙面的一阶微扰理论,在不考虑多重散射效应的情况下,利用电磁场边界条件给出的光学薄膜任一界面粗糙度引起的散射场在入射介质中的表达式,重点讨论了单层光学薄膜实现零散射的条件以及实现减散射的条件,理论研究结果表明:当膜层的光学厚度为/4的偶数倍时,单层薄膜要实现减散射就必须使单层膜的折射率大于基底的折射率,且空气-薄膜界面的微粗糙度必须小于薄膜-基底界面之间的微粗糙度。当膜层的光学厚度为/4的奇数倍时,单层薄膜的折射率小于基底的折射率,且膜层两个界面的粗糙度必须满足特定条件,才能实现减散射的效果。  相似文献   

9.
YbF3和ZnS薄膜的折射率和厚度的分光光度法测定   总被引:1,自引:0,他引:1  
乔明霞  黄伟  张彬 《激光杂志》2006,27(1):24-25
本文给出了一种简单而准确地确定光学薄膜折射率和厚度的方法。利用分光光度计分别测量光学薄膜样品以及基底透射率曲线,采用柯西(Cauchy)色散模型以及非线性单纯形优化法对透射率测量曲线进行拟合,从而确定薄膜的光学常数和厚度。采用电子束热蒸发和电阻热蒸发方法,分别在CaF2基底上镀制ZnS薄膜和在Al2O3基底上镀制YbF3薄膜,通过测量其在400nm-2600nm波段内的透射率曲线,计算出ZnS和YbF3薄膜材料的折射率色散曲线以及膜层厚度。  相似文献   

10.
傅里叶合成法设计渐变折射率薄膜   总被引:1,自引:0,他引:1  
傅里叶合成方法是一种可以根据期望的光谱特性曲线设计渐变折射率薄膜的方法.叙述了该方法的原理和Q函数的选择.介绍了修正方法使设计膜层折射率在可获得薄膜材料折射率范围内和把膜层匹配到入射介质和基底两端界面的技术.并用该方法设计ZnSe基底3~12μm红外增透渐变折射率薄膜,在设计波段平均透射率达到95%.最后对该方法作了相关评论.  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.
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   

13.
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   

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.
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   

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.
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   

18.
It is well known that adding more antennas at the transmitter or at the receiver may offer larger channel capacity in the multiple-input multiple-output(MIMO) communication systems. In this letter, a simple proof is presented for the fact that the channel capacity increases with an increase in the number of receiving antennas. The proof is based on the famous capacity formula of Foschini and Gans with matrix theory.  相似文献   

19.
The effect of laser microbeam trapping the bioparticles has been appfied widely in the biology .However the micromechanism of the acting that realizes the laser-microbeam trapping bioparticles is still lacking. In this paper ,the act microchenism of the gradiant force of laser microbeam for the bioparticles is analysed by means of quantum theory ,The result accords with our experiment.  相似文献   

20.
In order to diagnose the laser-produced plasmas, a focusing curved crystal spectrometer has been developed for measuring the X-ray lines radiated from a laser-produced plasmas. The design is based on the fact that the ray emitted from a source located at one focus of an ellipse will converge on the other focus by the reflection of the elliptical surface. The focal length and the eccentricity of the ellipse are 1350 mm and 0.9586, respectively. The spectrometer can be used to measure the X- ray lines in the wavelength range of 0.2-0.37 nm, and a LiF crystal (200) (2d = 0.4027 nm) is used as dispersive element covering Bragg angle from 30° to 67.5°. The spectrometer was tested on Shengnang- Ⅱ which can deliver laser energy of 60-80 J/pulse and the laser wavelength is 0.35 μm. Photographs of spectra including the 1 s2p ^1P1-1s^2 ^1S0 resonance line(w), the 1s2p ^3P2-1s^2 1S0 magnetic quadrupole line(x), the 1s2p ^3P1-1 s^2 ^1S0 intercombination lines(y), the 1 s2p ^3S~1-1 s^2 ^1S0 forbidden line(z) in helium-like Ti Ⅹ Ⅺ and the 1 s2s2p ^2P3/2-1 s622s ^2S1/2 line(q) in lithium-like Ti Ⅹ Ⅹhave been recorded with a X-ray CCD camera. The experimental result shows that the wavelength resolution(λ/△ 2) is above 1000 and the elliptical crystal spectrometer is suitable for X-ray spectroscopy.  相似文献   

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