关于迈克尔逊干涉仪测气体折射率的研究

<正> 物质折射率的测量或比较,在科学研究与工业应用上有很重要的意义。在固体材料中,测量各种光学玻璃或其他光学材料的折射率和色散曲线是很重要的。对于气体或液体,折射率的测定和色散现象的研究,也有重要的工业上的应用和科学研究的意义。在矿井中,要经常分析空气中混杂的有害气体(如沼气)的浓度。在锅炉设备中,为了确定燃烧的情况,也需要不断检查烟道气体中CO_2     

用迈克尔逊干涉仪测波长实验的改进

一、原实验简单介绍在图(1)中,S为单色光源,M_1和M_2为两反射镜,P_1为半镀膜分光板,P_2为补偿板.当由光源S发出的光经P_1分光后得光束(1)和光束(2),若两束光各与M_1和M_2垂直,则经M_1和M_2反射后,两光束在a点相会后其光程差为     

用分光计测液体折射率

根据分光计测定棱镜折射率的方法,提出了可以用分光计测定透明液体的折射率,从理论上推导出最小偏向角及此时入射角、折射角满足的条件,并且得出光线通过平板玻璃时不会发生折射,只会平移的结论.     

基于迈克尔逊干涉仪测金属线胀系数

金属线胀系数的测量是大学物理实验中一个重要的实验项目,提出一种新的结合迈克尔逊干涉仪测量金属线胀系数的新方法。利用迈克尔逊干涉仪可以测量微小长度的特点,测定金属在环境温度变化时细微的伸长量,通过高速摄像机记录干涉条纹变化的个数,并且利用常用的视频编辑软件premiere对干涉条纹的变化进行了数字化的处理,避免了迈克尔逊干涉仪同心圆形环条纹数变化太快而引起的测量误差,大幅度提高了测量精度,是光学和热学实验的有机的结合。     

迈克尔逊干涉仪测角度改变量

讨论了迈克尔逊干涉仪补偿板的作用和补偿板角度改变量的测量方法。补偿板的转动会引起光程差的变化，产生干涉条纹数目的变化。通过测量条纹的改变数目，算出补偿板的角度改变量。文中所述方法新颖，精确度较高。     

用等厚干涉测液体折射率

采用劈尖实验装置在不改变劈尖膜条件下,同时测得空气膜和液体膜的干涉条纹宽度,并进一步计算出实验结果,从而得到一种方便求出液体折射率的新方法.     

迈克尔逊干涉仪测量平行透明物厚度或折射率

迈克尔逊干涉仪可较方便的获得稳定的等倾干涉现象。光路中介质特性的变化直接影响等倾干涉条纹的分布状况。用等倾干涉测量介质厚度或折射率,一般须避免对难于测量的入射光倾角和干涉条纹绝对级次等量的确定,传统的方法往往采取移动反射镜或改变被测介质的几何位置以获得等倾条纹中心级次改变来实现。如果合理利用透镜的成像原理和入射光小角度下良好的近似关系,则可简便地通过测定等倾干涉条纹直径,来确定平行透明物的厚度或折射率。     

利用迈克尔逊干涉仪测杨氏弹性模量的方法

提出一种借助于迈克尔逊干涉仪对金属丝杨氏弹性模量高准确度的测量方法。通过计量迈克尔逊干涉仪产生的干涉条纹变化数目,能准确测得金属丝微小长度变化量,进而测得其杨氏弹性模量。相比于传统的光杠杆法测微小位移,仪器结构简单,可操作性强。测得的数据计算结果表明:测量精度高,结果可靠。     

用Flash 5模拟迈克尔逊干涉仪

Flash5是最新推出的网页电影动画软件，它配合Dreamweaver和Fireworks，可以制作出顶级的网页。文中应用F1ash5制作物理课件，最后制成独立影片发布。     

一个研究型实验项目的探讨--利用迈克耳逊干涉仪测气体折射率

“研究型”物理实验的开设对激发学生的求知欲、拓宽其知识面、培养其创新思维能力等方面具有重要意义.文章以迈克耳逊干涉仪实验为例,通过在实验装置中增设可调压强的气室和CCD图像采集系统,实现对干涉图样的实时观察和气体折射率的较精确测量.实验设计还考虑到了实验内容及其难度的可深入与拓展空间,具有很强的研究型实验特点,并且可以根据适当的教学设计将此实验开设成综合性或设计性实验.     

空气折射率测量实验的改进

普通的迈克尔逊干涉仪测量空气折射率遇到的主要问题是由于光程差太大,使得干涉条纹很密无法计数。该文介绍的用测微目镜将干涉条纹放大,再进行测量的方法很好地解决了这个问题。     

分光计测三棱镜折射率的探讨

介绍了如何用分光计精确确定三棱镜顶角和最小偏向角,以及测量方法.结合分光计测三棱镜折射率的例子,进行了具体分析,给出了其测量不确定度的最终评定.     

测定薄透镜曲率半径和折射率的简单方法

介绍了薄透镜焦距测定中观察到的一种反射成像现象,指出利用薄透镜正反两次反射成像可较好地测定其折射率和前后表面的曲率半径。     

棱镜玻璃折射率测定实验中的一个问题

测一梯形棱镜的折射率时，找不到最小偏向角的位置，分析其原因，提出测量方法，分析总结折射率测定实验中玻璃棱镜角的选择原则。     

液体折射率的干涉法测量

液体折射率的测量在工农业生产中非常重要,利用牛顿环干涉原理测量液体的折射率的方法,能够方便、准确地测量出液体的折射率,测量结果准确,测量过程简单。     

A terahertz metamaterial with unnaturally high refractive index

Controlling the electromagnetic properties of materials, going beyond the limit that is attainable with naturally existing substances, has become a reality with the advent of metamaterials. The range of various structured artificial 'atoms' has promised a vast variety of otherwise unexpected physical phenomena, among which the experimental realization of a negative refractive index has been one of the main foci thus far. Expanding the refractive index into a high positive regime will complete the spectrum of achievable refractive index and provide more design flexibility for transformation optics. Naturally existing transparent materials possess small positive indices of refraction, except for a few semiconductors and insulators, such as lead sulphide or strontium titanate, that exhibit a rather high peak refractive index at mid- and far-infrared frequencies. Previous approaches using metamaterials were not successful in realizing broadband high refractive indices. A broadband high-refractive-index metamaterial structure was theoretically investigated only recently, but the proposed structure does not lend itself to easy implementation. Here we demonstrate that a broadband, extremely high index of refraction can be realized from large-area, free-standing, flexible terahertz metamaterials composed of strongly coupled unit cells. By drastically increasing the effective permittivity through strong capacitive coupling and decreasing the diamagnetic response with a thin metallic structure in the unit cell, a peak refractive index of 38.6 along with a low-frequency quasi-static value of over 20 were experimentally realized for a single-layer terahertz metamaterial, while maintaining low losses. As a natural extension of these single-layer metamaterials, we fabricated quasi-three-dimensional high-refractive-index metamaterials, and obtained a maximum bulk refractive index of 33.2 along with a value of around 8 at the quasi-static limit.     

液体折射率的干涉法测量

液体折射率的测量在工农业生产中非常重要,利用牛顿环干涉原理测量液体的折射率的方法,能够方便、准确地测量出液体的折射率,测量结果准确,测量过程简单.     

Three-dimensional optical metamaterial with a negative refractive index

Metamaterials are artificially engineered structures that have properties, such as a negative refractive index, not attainable with naturally occurring materials. Negative-index metamaterials (NIMs) were first demonstrated for microwave frequencies, but it has been challenging to design NIMs for optical frequencies and they have so far been limited to optically thin samples because of significant fabrication challenges and strong energy dissipation in metals. Such thin structures are analogous to a monolayer of atoms, making it difficult to assign bulk properties such as the index of refraction. Negative refraction of surface plasmons was recently demonstrated but was confined to a two-dimensional waveguide. Three-dimensional (3D) optical metamaterials have come into focus recently, including the realization of negative refraction by using layered semiconductor metamaterials and a 3D magnetic metamaterial in the infrared frequencies; however, neither of these had a negative index of refraction. Here we report a 3D optical metamaterial having negative refractive index with a very high figure of merit of 3.5 (that is, low loss). This metamaterial is made of cascaded 'fishnet' structures, with a negative index existing over a broad spectral range. Moreover, it can readily be probed from free space, making it functional for optical devices. We construct a prism made of this optical NIM to demonstrate negative refractive index at optical frequencies, resulting unambiguously from the negative phase evolution of the wave propagating inside the metamaterial. Bulk optical metamaterials open up prospects for studies of 3D optical effects and applications associated with NIMs and zero-index materials such as reversed Doppler effect, superlenses, optical tunnelling devices, compact resonators and highly directional sources.