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1.
针对材料发射率数据日益增长的需求,建立了超高温傅里叶变换(FT)光谱发射率测量系统.为校准材料光谱发射率的测量结果,建立了包含辐射传交换、固体热传导、辐射测温在内的发射率校准模型.通过校准模型定量分析了试样辐射热损、厚度、热导率等因素引起的发射率测量误差.结果表明,这些因素均导致试样测量温度偏高,而发射率测量结果偏低.测量了真空环境下2000℃时纯度为99.99%石墨的光谱发射率曲线.采用模型校准后的发射率曲线与文献比较,取得了比较一致的结果.该方法在超高温发射率测量技术中可以有效地提高测量精度.  相似文献   

2.
建立了基于集成黑体法的材料高温红外光谱发射率测量理论模型,重点讨论了不等温集成黑体空腔有效发射率、观测因子、样品材料外推温降因素的影响.基于集成黑体法搭建了以傅里叶红外光谱仪为红外辐射探测系统的高温红外光谱发射率测量装置.基于蒙特卡罗光线追迹法数值开展了集成黑体有效发射率数值模拟,并进行了实验验证.讨论了辐射源尺寸效应...  相似文献   

3.
建立了基于集成黑体法的材料高温红外光谱发射率测量理论模型,重点讨论了不等温集成黑体空腔有效发射率、观测因子、样品材料外推温降因素的影响。基于集成黑体法搭建了以傅里叶红外光谱仪为红外辐射探测系统的高温红外光谱发射率测量装置。基于蒙特卡罗光线追迹法数值开展了集成黑体有效发射率数值模拟,并进行了实验验证。讨论了辐射源尺寸效应、光谱响应度线性度等非理想因素对集成黑体法高温光谱发射率测量的影响。开展了石墨材料在1 000℃、1 300℃、1 500℃的红外光谱发射率实验研究,并与已公开发表的测量结果进行了比对。本文结果与文献数据优于5%的良好一致性,验证了集成黑体方法在高温发射率测量中的可行性。  相似文献   

4.
脉冲加热材料热物性多光谱动态测量装置的研制   总被引:2,自引:0,他引:2       下载免费PDF全文
提出一种将多光谱测温法和积分球反射法相结合的脉冲加热技术测量材料热物性的新方法。基于积分球反射法,利用多光谱测温法获得材料在多个光谱下的辐射信息,可同时获得试样在多个光谱下的法向光谱发射率。介绍了利用该方法的脉冲加热瞬态热物性测量装置的各组成部分及其工作原理,该装置能 同时测量带状试样的比热、电阻率、全波长半球发射率及多个光谱下的法向光谱发射率。  相似文献   

5.
材料表面的发射率特性与许多因素有关,温度是影响发射率最重要的因素之一,由于测量条件的限制,只能测量有限温度范围内发射率,对其他温度与发射率的关系不能准确得出。通过大量文献的发射率与温度测量数据,利用Matlab软件仿真出发射率与温度曲线。从曲线的走势分析,建立了线性和指数两种数学模型。选用文献提供的测量数据,分别计算出两种模型的未知参量,分别模拟出发射率与温度的曲线,与原始的测量曲线比较分析,发现指数发射率模型适合该材料。分别用两种数学模型对其他文献提供的数据进行模拟仿真,模型与实际测量的相对误差均小于2%,总结了适合两种模型的材料特性。  相似文献   

6.
红外光谱发射率是战机蒙皮重要的红外隐身参数之一,为消除大气等外界因素对红外辐射特性测试结果的干扰,建立一种基于小波神经网络的目标红外辐射亮度模型,利用这种模型对测试样本进行网络训练,建立3~5 μm 和8~12 μm 波段红外辐射亮度模型,进而计算不同波长下目标的光谱发射率。通过与标准黑体对比,验证所建小波神经网络模型的光谱发射率与黑体实际的光谱发射率相比,最大相对误差约为2%,并将该方法应用于飞机蒙皮的光谱发射率计算。  相似文献   

7.
光谱发射率测量技术   总被引:3,自引:1,他引:3  
论述了光谱发射率在航天、航空、国防、军事及国民经济各领域中的实际应用和重要意义.材料光谱发射率的影响因素很多,且应用背景差异较大,各国分别建立了各具特色的发射率测量装置.根据测量特点及应用范围,发射率测量方法分4大类:量热法、反射法、能量法和多波长法.针对每种测量方法介绍了基本原理、装置特点、技术指标和发展现状.简单介绍了基于红外傅里叶分析光谱仪建立的光谱发射率测量系统,进而描述了材料发射率在重要领域的具体应用情况.分析了我国目前在发射率测量技术方面存在的问题,展望了我国发射率测量技术的发展趋势和发射率数据库方面的进一步工作.  相似文献   

8.
光纤式20波长辐射高温计的研制   总被引:2,自引:0,他引:2  
基于多光谱辐射测温理论,研制了20波长光纤辐射高温计.利用多光谱辐射测温法获得材料在多个光谱下的辐射信息,从而计算出试样的真温和在多个光谱下的法向光谱发射率.利用光学光纤将光学探头接收到的光信号进行远距离传输,增加了测量的便利性和整套装置对测量环境的适应能力;精密的多量程自动切换电路扩大了温度测量范围,并降低了环境噪声对测量结果的影响;专用的微型工控机控制系统提高了这套装置独自工作及与其它设备进行协调合作的能力.整套装置可测量的温度范围是800-3500℃,测量精度小于1%.  相似文献   

9.
材料法向光谱发射率测量方法研究   总被引:1,自引:0,他引:1  
本文报道利用红外分光光度计和微机系统,采用二次测量技术,测量材料表面法向光谱发射率的基本原理和测试方法。推导出光谱发射率的计算公式,对引起测量误差的诸因素进行讨论,并实测了几种材料法向光谱发射率曲线。  相似文献   

10.
基于多光谱辐射测温技术,提出一种无需假设发射率模型的梯度投影算法,并对6种发射率模型进行了仿真计算.结果表明:梯度投影法反演结果误差小于20 K,发射率反演结果的趋势与模型吻合.梯度投影法属约束优化算法,与多光谱辐射测温技术结合可避开发射率无法确定需要假设模型的难题,开辟了多光谱辐射测温新的研究思路.  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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