共查询到20条相似文献,搜索用时 218 毫秒
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利用白光干涉原理,借助迈克耳孙干涉仪对肥皂膜的厚度进行了非接触测量.在干涉条纹宽窄相同的条件下,对不同层数的肥皂膜进行对比测量;在干涉条纹宽窄不同的条件下,对相同层数的肥皂膜进行对比测量;通过计算给出了膜的中心厚度和不确定度,对比分析了各种条件下测量时误差产生的原因.结果表明:单层、双层膜适合在宽条纹下测量,四层膜适合在窄条纹下测量. 相似文献
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提出了使用用迈克尔逊干涉仪,改变光源入射方式及观测方式以获得稳定、清晰等厚干涉现象的方法.探究了在光路中插入的被测透明介质如何对等厚干涉条纹产生影响,并导出了被测介质厚度、折射率及旋转角度与等厚干涉条纹移动量之间的关系.实现对透明介质厚度、折射率进行简练、快速的同时测量. 相似文献
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本文应用薄板纯弯曲理论,导出薄板变形后的中面为鞍形曲面。在变形的透明平板玻璃条中央放一玻璃片巧妙地形成了空气膜,通过干涉装置则能看到平时不多见的双曲线等厚干涉条纹。通过对双曲线干涉条纹两顶点间的距离的测量,可求出相应的 相似文献
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利用785 nm波长激光作为激发源,测量了超二代微光像增强器Na2KSb(Cs)多碱光电阴极的荧光谱.试验中发现该荧光谱不是一条光滑的高斯型曲线,而是一条在高斯型荧光谱上叠加了一定频率间隔小锯齿峰的曲线.经实验验证和理论分析证明该荧光谱上的小锯齿峰是一种干涉条纹,与超二代微光像增强器的结构有关.干涉条纹之间的间距与相邻两干涉峰波长的乘积成正比,与超二代微光像增强器的近贴聚焦距离成反比.干涉条纹调制度大小与Na2KSb(Cs)多碱光电阴极的厚度成反比.通过测量超二代微光像增强器Na2KSb(Cs)多碱光电阴极荧光谱上两相邻干涉条纹的间距和调制度,就可以测量或比较出不同超二代微光像增强器Na2KSb(Cs)多碱光电阴极的膜厚、近贴聚焦距离.研究结果对提高超二代微光像增强器阴极灵敏度和分辨力提供了一个有效的分析手段. 相似文献
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一般国内的大学物理和大学物理实验教材都只介绍干涉圆条纹和直线干涉条纹,用迈克耳孙干涉仪可以调制出椭圆和双曲线干涉条纹;但对条纹形成的理论推导很少涉及.本文根据点光源双光束干涉理论,分析基于点光源照明的迈克耳孙干涉实验中所产生的各种可能的干涉条纹:双曲线形干涉条纹、圆形干涉纹、椭圆形干涉纹及直线形干涉纹的形成条件.本文也对等倾干涉条纹、等厚干涉条纹与既非等倾也非等厚干涉条纹的机理进行分析和比较.通过对每一种干涉图样的解析分析和比较,旨在对迈克耳孙干涉实验有更全面和更深刻的了解. 相似文献
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关于用干涉仪测膜厚问题的两点讨论郑永星(天津大学应用物理学系)一、干涉条纹突变移动量的测量问题本刊1993年第6期《用迈克尔孙干涉仪测薄膜厚度》一文断言,在迈氏干涉仪的一臂上置人折射率为n的薄膜,因“导致干涉条纹的移动是个突变过程,无法测出干涉条纹移... 相似文献
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Determination of Thickness and Optical Constants of ZnO Thin Films Prepared by Filtered Cathode Vacuum Arc Deposition 下载免费PDF全文
ZnO thin films are prepared on glass substrates by filtered cathode vacuum arc (FCVA) deposition technique. A new method is demonstrated to extract the refractive index, thickness and optical band gap of ZnO thin films from the transmission spectrum alone. The refractive index is calculated from the extremes of the interference fingers. The transmission spectrum is divided into two terms, non-interference term and interference effect term. The thickness of thin films is calculated by simulating the interference term, and the non-interference term is used to calculate optical band gap with the gained thickness. The results are compared with measurements by using an ellipsometry and a scanning electron microscope. 相似文献
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V. V. Filippov 《Optics and Spectroscopy》2006,101(3):458-462
For determining the optical constants and the thickness of thin films (including strongly absorbing films) by the spectrophotometric method, we propose to deposit them on intermediate films formed on strongly reflecting substrates. Due to this, an interference pattern depending on the optical constants and the thickness of the film under study will be observed in the reflectance spectrum. The method of envelopes of the extrema in the reflectance spectrum that is based on the iterative approach is developed for studying two-film systems. 相似文献
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Fringes of equal chromatic order in transmission across a thin liquid or a thin solid sample inside a wedge interferometer, followed with a grating spectrograph, are produced. A single-shot interferogram of the air and sample regions is recorded. Locations of fringes maxima in the air region are fitted in a numerical procedure based on Cauchy's dispersion function. Then it is used for measuring the interferometric gap thickness. The order of interference in the sample region is represented by a third-order polynomial in the wavenumber for deducing the sample group refractive index. An error analysis of the measured group refractive index is given. The method is applied for measuring the group refractive index of water and mica samples across the visible spectrum. The method measures both the sample thickness and its group refractive index. It is static with no moving parts and suitable for thin liquid or solid samples without immersion liquids. 相似文献
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Waves interference inside thin films creates fine structures in the thermal emission spectrum of film when the magnitude of film thickness is of the same order than the coherence length of light. Here, we present an alternative to the theory of partially coherent light to explain these ripples pattern and easily predict the radiative properties of films in intermediate regime. The starting point of this theory is based on the observation that unlike vacuum, matter supports the presence of unstable electromagnetic waves with a finite lifetime. For thin absorbing films, we demonstrate that many of these metastable states are quantified and can be excited by an external radiation field. A direct connection is then established between the peaks of emission and these modes. These results open new prospects for the theoretical study and modelling of radiative exchanges inside and between microscale media. 相似文献
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We have studied the dependence of the photoluminescence (PL) spectrum on the doping level and the film thickness of n-GaAs thin films, both experimentally and theoretically. It has been shown theoretically that modification of the PL spectrum of p-type material by p-type doping is very small due to the large valence-band hole effective mass. The PL spectrum of n-type material is affected by two factors: (1) the electron concentration which determines the Fermi level in the material; (2) the thickness of the film due to re-absorption of the PL signal. For the n-type GaAs thin films under current investigation, the doping level as well as the film thickness can be very well calibrated by the PL spectrum when the doping level is less than 2×1018 cm-3 and the film thickness is in the range of the penetration length of the PL excitation laser. PACS 78.20.-e; 78.55.Cr; 78.66.Fd 相似文献
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由于普通的化学气相沉积法制作高掺Sn的二氧化硅薄膜比较容易产生结晶,而溶胶-凝胶法制备薄膜化学组成比较容易控制,可以制作出掺Sn浓度较大的材料。文章采用了溶胶-凝胶的方法制备出了66 mol%和75 mol%两种不同浓度的掺Sn的SiO2薄膜,用浸渍法多次提拉薄膜以增加薄膜的厚度,之后用紫外-可见分光光度计测量了薄膜的透射光谱。之前基于透射光谱的方法计算玻璃基底上薄膜的光学参数都是针对单面薄膜,该文针对浸渍法产生的双面薄膜,建立了相对应的薄膜模型,并分别用包络线法计算出了两种不同薄膜样品的光学参数。计算结果表明两种不同薄膜样品的折射率随着波长的增加而增加,薄膜的厚度都为900 nm左右。 相似文献
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Crystallization and annealing effects of sputtered tin alloy films on electromagnetic interference shielding 总被引:1,自引:0,他引:1
Sn, Al and Cu not only possess electromagnetic interference (EMI) shield efficiency, but also have acceptable costs. In this study, sputtered Sn-Al thin films and Sn-Cu thin films were used to investigate the effect of the crystallization mechanism and film thickness on the electromagnetic interference (EMI) characteristics. The results show that Sn-xAl film increased the electromagnetic interference (EMI) shielding after annealing. For as-sputtered Sn-xCu films with higher Cu atomic concentration, the low frequency EMI shielding could not be improved. After annealing, the Sn-Cu thin film with lower Cu content possessed excellent EMI shielding at lower frequencies, but had an inverse tendency at higher frequencies. For both the Sn-xAl and Sn-xCu thin films after crystallization treatment, the sputtered films had higher electrical conductivity, however the EMI shielding was not enhanced significantly. 相似文献
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Antonín Vašíček 《Czechoslovak Journal of Physics》1954,4(2):204-219
Formulas for the reflection of light from glass (i. e. a dielectric) coated with a thin non-metallic film are generalized for the case of the reflection of light from a metal coated with a thin non-metallic film, e. g. a film of aluminium oxide on aluminium. It is shown how the refractive index and the thickness of the aluminium oxide film on an aluminium mirror can be determined by measurements in polarized light. In conclusion the results of Drude's classical theory of thin non-metallic films on metallic mirrors are compared with the results obtained by the author on the basis of the interference of light in thin films. 相似文献