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实时全息干涉计量中时问序列条纹位相的测量方法 总被引:1,自引:1,他引:0
针对实时全息干涉计量的特点,结合相移位相测量技术,提出一种利用物体本身变化产生的位相变化来实现实时全息干涉计量中时间序列条纹位相的测量方法,通过分析得到不同时刻位相变化及整个变化过程中位相累计变化的计算公式。 相似文献
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全息干涉计量和散斑技术已广泛应用于机械位移、振动、应力和变形测量。在全息干涉计量术方面,已采用了双曝光、多次曝光、时间平均曝光,以及光束调制和频闪曝光等技术。另外,已研究了条纹定位和三维条纹图形分析技术。最近,在条纹分析中采用了矩阵法和张量计算,从而产生了若干种应变分析技术。利用外差干涉计量术,使相位检测精度提高到千分之一。在散斑干涉计量和照相方面,已经过了研究阶段,开始走向实用。散斑技术是对全息干 相似文献
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一、引言 四边固定的矩形板广泛应用在工程技术的各个领域中。研究它们在外力作用下的变形,对于工程设计和部件的检验都是很重要的。 不少作者曾用经典的方法和全息干涉计量术的方法测量了四边固定的方形板在均匀应力作用下的变形。本文利用全息干涉计量术的二次曝光法测量了四边固定的矩形板在点力作用下的变形,并把测量结果与理论计算结果作了比较。 二、原理 在全息干涉计量术的二次曝光法中,再现象的光强分布 相似文献
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目前对于多通道全息术已经作了比较充分的研究。这种技术对多种不同物体的记录和比较或对同一物体的多种状态的记录与比较是十分有用的。已经成功地用于干涉计量的多通道全息术有对记录干板进行区域编码记录和采用多路参考光进行编码记录技术,实时全息术和夹层全息术也可以进行多状态全息干涉计量,但需要有精确的复位装置和特殊的编码装置,技术上也很复杂。这里提出一种实现多通道全息干涉计量的简易方法。 相似文献
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聚对苯撑苯并双(口恶)唑发光及其器件制备 总被引:2,自引:0,他引:2
采用光谱技术,研究了聚对苯撑苯并双(口恶)唑(PBO)溶液的光敏发光特性,并用相对法估算出溶液发光效率在50%范围.结合光谱技术、半导体电学和电化学等研究手段,具体研究了以PBO为发光层的单层电致发光器件,研究结果显示,电致发光与薄膜的光致发光有具有相同的发光中心,峰值位于510 nm左右.同时发现,由于存制备过程中不同处理条件使得不同厚度薄膜残留的掺杂物质浓度不同,从而引起薄膜的导电性的不同.使得器件的阈值场强随PBO厚度的减小而逐渐增加. 相似文献
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Aluminium was a primary material for interconnection in integrated circuits (ICs) since their inception. Later, copper was introduced as interconnect material which has better metallic conductivity and resistance to electromigration. As the aggressive technology scaling continues, the copper resistivity increased because of size effects, which causes increase in delay, power dissipation and electromigration. The need to reduce the resistor-capacitor??????? delay, dynamic power utilisation and the crosstalk commotion is as of now the fundamental main impetus behind the presentation of new materials. The purpose of this paper is to do a survey of interconnect material used in IC from introduction of ICs to till date. This paper studies and reviews new materials available for interconnect application which are optical interconnects, carbon nanotube (CNT), graphene nanoribbons (GNRs) and silicon nanowires which are alternatives to copper. While doing a survey of interconnect material, it is found that multiwalled CNTs, multilayer GNR and mixed CNT bundles are promising candidates and are ultimate choice that can strongly address the problems faced by copper but on integration basis copper would last for coming years. 相似文献
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We demonstrate a novel scheme to generate ultrawideband (UWB) monocycle and doublet pulses byinputting a dark return-to-zero (RZ) signal into a delay interferometer (DI), which accords with the general features in future applied UWB system, namely, single optical source input, simple configuration and passive device. The two polarized interferential beams have a time delay and a phase difference when they propagate through the DI. By adjusting polarization controllers (PCs), the total phase difference, i.e., the sum of the relative opticalphase difference between two orthogonally polarized components caused by PCs and the optical-phase shift due to birefringence of the polarization-maintaining fiber (PMF), the orientation angle of the polarization beamsplitter (PBS) relative to the two axes of the PMF are able to be changed and controlled. When the appropriate conditions are met, UWB monocycle and doublet pulses are generated conveniently. 相似文献
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在银胶体系中罗丹明B单分子水平上拉曼光谱研究 总被引:1,自引:1,他引:0
采用表面增强托曼散射(SERS)技术,比较了单分子水平上银胶纳米体系中罗丹明B(RhB)浓度为10^-11mol/L以下的拉曼光谱和通常单分子水平上罗丹明6G(Rh6G)浓度在10^-11mol/L的拉曼光谱,无论自由沉积在玻璃表面还是在液体环境下的结果显示,单分子水平上Rh B的拉曼光谱灵敏度是Rh 6G的2倍多。因此,利用RhB作为探测试剂将能够提供更加丰富的信息,这对单分子的光谱研究以及高灵敏度探测试剂的应用研究具有重要的意义。 相似文献
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OBIST methodology incorporating modified sensitivity of pulses for active analogue filter components
In this paper, oscillation-based built-in self-test method is used to diagnose catastrophic and parametric faults in integrated circuits. Sallen–Key low pass filter and high pass filter circuits with different gains are used to investigate defects. Variation in seven parameters of operational amplifier (OP-AMP) like gain, input impedance, output impedance, slew rate, input bias current, input offset current, input offset voltage and catastrophic as well as parametric defects in components outside OP-AMP are introduced in the circuit and simulation results are analysed. Oscillator output signal is converted to pulses which are used to generate a signature of the circuit. The signature and pulse count changes with the type of fault present in the circuit under test (CUT). The change in oscillation frequency is observed for fault detection. Designer has flexibility to predefine tolerance band of cut-off frequency and range of pulses for which circuit should be accepted. The fault coverage depends upon the required tolerance band of the CUT. We propose a modification of sensitivity of parameter (pulses) to avoid test escape and enhance yield. Result shows that the method provides 100% fault coverage for catastrophic faults. 相似文献
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石墨烯基电子学研究进展 总被引:3,自引:0,他引:3
综述了石墨烯晶体的能带结构和独特的电子性质,如双极性电场效应、单双层石墨烯效应、衬底效应、石墨烯纳米带(GNR)带隙等特殊效应的研究现状。介绍了石墨剥落技术、外延生长和化学气相淀积(CVD)等石墨烯材料的制备以及表征方法。列举了石墨烯在电子、显示、太阳电池、传感器和氢存储等方面的应用,如在石墨烯场效应管、石墨烯纳米带场效应管(SET)、石墨烯单电子晶体管、石墨烯金属晶体管、石墨烯基纳米电子机械系统(NEMS)、石墨烯分子开关以及石墨烯基高电子迁移率晶体管(HEMT)制备方面的应用。人们已经研究出不同栅长的n/p型顶栅石墨烯场效应管(GFET),并采用标准的S参数直接表征器件的高频性能。理论和实验表明,所有石墨烯纳米带场效应管(GNRFET)在室温下工作的前提是GNR的带宽尺寸小于10nm,并具有半导体场效应管的性能。 相似文献