0.2秒分光计测量玻璃折射率操作方法的改进

一、最小偏向角法测量玻璃折射率的基本原理用最小偏向角法测量玻璃折射率是几种折射率测量方法中精度最高的一种,其测量不确定度最高可达1×10~(-6)量级。在0.2秒分光计上测量玻璃折射率即采用此法,基本原理如图1所示。     

两种高准确度测量光学玻璃折射率方法的比较

实验使用德国Trioptics公司生产的SpectroMaster HR UV-VIS-IR型折射率测量设备,采用最小偏向角法和封闭式直角照射法,对多种材料玻璃的不同谱线进行折射率测量,并分析比较这两种方法。实验结果为最小偏向角法不确定度1.1×10~(-6),封闭式直角照射法不确定度2.2×10~(-6)。最小偏向角法优于封闭式直角照射法,但如果能解决平行光管出射光的平行度等因素,封闭式直角照射法同样有前景。精密测量光学玻璃材料折射率对于航天、航空领域有重要意义。     

C#语言在玻璃材料折射率计量技术研究中的应用

为开展高精度的玻璃材料折射率计量技术研究,实验室购置德国Triotics公司生产的SpectroMaster HR UV-VIS-IR型折射率测量设备,对7种标准物质在253～2325nm波段下进行高精度折射率的测量.针对玻璃材料折射率计算,设计了C#语言计算软件,能对最小偏向角法和封闭式直角照射法进行折射率计算和通过...     

红外材料低温折射率测定:不确定度分析

文章从常见的折射率测定方法入手,分析了最小偏向角法和垂直入射法的误差灵敏度和合成不确定度,得出在相同顶角和偏向角的情况下最小偏向角法测量的不确定度约为垂直入射法1/2 的结论.同时,分析了折射率测定时光源带宽引起的色散对测量精度的影响,利用Herzberger 色散方程估计了ZnSe 的色散情况,获得了在5～10μm 波段的色散约为5×10-4 μm-1,从而确定了折射率测量的光源带宽需小于20 nm 的要求.本文从误差控制角度出发,对比了最小偏向角法和垂直入射法的精度,为我们红外材料低温折射率测量的下一步工作奠定了基础.     

JC—1型精密测角仪的研制

本文介绍了一种高精度、积木式、多功能的能进行动态测量的精密测角仪,动态测角不确定度小于0.19角秒;该机能测角、测光栅、测量光学材料折射率等,测折射率能自动寻找最小偏向角自动测样品顶角,并打印测量结果。     

标准光楔偏向角的测量

PJ—1光电光楔测角仪是利用干涉原理直接测量光线通过光楔时产生的偏向角,而不必通过测量光楔的楔形角和折射率间接地计算出偏向角,因而避免了折射率测量误差的影响,提高了测量精度。同时,由于本仪器采用光电动态对准和激光测长、电子数显等先进技术,操作方便,测量迅速,从而大大避免了测量环境波动的影响,测量结果稳定。最大测角误差为0″.1。     

液体折射率测量的一种有效途径

本文介绍了一种利用迈克尔逊干涉仪光路加入楔形样吕池进行液体折射率测量的方法，并用此方法精确测量了液态ＳＣＮ－Ｂｔｈ合金的折射率，该方法简单易行，测量精度高，易于温度控制，适用于不同温度下的各种液体折射率的精确测量。     

特高折射率玻璃微珠的制备及折射率测量方法

采用高温吹制工艺制备出直径３０～５５μｍ、特高折射率玻璃微珠。以近轴光线成像的理论为基础，提出了用光学显微镜测量玻璃微珠折射率的简便方法。测得所制备玻璃微珠的平均折射率为２．４７；分析和讨论了测量方法的误差和实用性。     

一种液体折射率的薄膜干涉测量方法

理论分析表明在镀有金属分光膜的玻璃介质和金属介质构成的几何楔形成的斐索干涉条纹中,相长干涉并不位于相邻的两相消干涉的中央,而是存在一明显偏移,这一偏移与引入几何楔中待测液体的折射率相关.基于该原理,提出了一种新的折射率测量的方法,并对该方进行了实验验证.该方法不需要利用标准液对光学几何量进行标定,测量范围广.     

高精度全自动V棱镜折射仪的改进

利用CCD成像与图像处理的机器视觉自动对准技术,在考虑了空气折射率对V棱镜折射仪测量精度影 响的基础上,对V棱镜折射仪原有的原理公式重新进行数学建模,提出了一种改进全自动V棱镜折射仪的方案。 用已知折射率的玻璃标准样块对改进后的仪器进行了评定,测试结果与标定值绝对误差不超过± 3 X 10^-6,测量重 复性优于1 x10^-6。     

Using minimum deviation of a secondary rainbow and its application to water analysis in a high-precision, refractive-index comparator for liquids

A new method for measuring the refractive-index difference of a liquid has been developed. The liquid to be measured is contained in a 60-mm-diameter, cylindrical glass cell, and a He-Ne laser light is passed into the cell so that the laser light incidence fulfills the condition of minimum deviation. In this condition, the beam emerging from the cell has a fine interference fringe. The position of the interference fringe is read out as a marker to measure the deflection of the laser light. Directly reading the peak shift of the interference fringe makes it easy to obtain the refractive index difference of the liquid with a fairly high precision of at least 6 x 10(-6). Further high precision is potentially expected to be realized by use of an improved data analysis treatment of the overall interference fringe pattern.     

一种测量透明平行平板折射率的新方法

通过测量激光细光束经平行平板玻璃所产生的位移,可确定平行平板的的折射率。本文阐述了该方法的测量原理,给出了测量公式,并详细分析了测量误差。计算机模拟计算结果表明,当平板厚度为50mm时,如果入射角测量标准偏差为1”,平板厚度和光线位移量测量标准偏差均为0.001mm,则折射率测量的标准偏差可达6×10~(-5),此时入射角约55°。     

代稀土无Pb高折射率光学玻璃（TiF700／350）的研究

研究了实用的ＢａＯ－ＴｉＯ２－ＳｉＯ２系代稀土无铅光学玻璃，运用玻璃物理性质的计算方法来拟合玻璃组织，并讨论了可形成稳定玻璃的组成范围，这种玻璃具有高折射率（ｎｄ＝１．７０），低密度（ｐ＝３．０３）与适中的色散系数（Ｖ＝３５），适于实用，Ａｌ２Ｏ３及ＭｇＯ的存在使该系统析晶倾向增大。     

TiO2\FTO镀膜玻璃色饱和度的数值模拟

本文以具有较高折射率的材料——二氧化钛(TiO2)替代自身折射率较低的材料——SiCOx作为氟掺杂氧化锡(FTO)镀膜玻璃中间层薄膜,通过数值模拟计算的方法主要研究了TiO2\FTO镀膜玻璃的表面色饱和度控制表现,并与传统的SiCOx\FTO镀膜玻璃就色饱和度控制表现进行了对比,结果发现TiO2\FTO镀膜玻璃具有更加优异的表面色饱和度控制表现,适合进行实际应用推广。     

Simulation study on refractometry by the rainbow method

To realize a high-precision refractive-index measurement by the rainbow method by use of multifringes, the characteristics of several orders of supernumerary bow fringes are made clear by a simulation based on the Huygens-Fresnel principle. The fringe intervals computed are precisely coincident with those obtained in experiments. As a result a suitable combination of the diameter of the cylinder containing the sample and the beam size of the laser has been determined. By use of the characteristic curve of the deviation angle versus the refractive index for each fringe and by the statistical treatment, measurement with high precision was demonstrated.     

PbSe量子点掺杂玻璃折射率的实验测量

为了明确PbSe量子点掺杂硅酸盐玻璃的光学特性,利用阿贝折射仪和带激光光源的分光计测量了其折射率,多次重复测量表明,该组分的量子点掺杂玻璃具有较稳定的折射率（nD=1．5981±0．0027）,是非常理想的光纤制备材料。实验还表明,阿贝折射仪可以用来快速准确地测量某些固体材料的折射率,为研究新材料的折射率特性提供了一种快速测量方法。     

Spectrometric determination of the refractive index of optical wave guiding materials used in lab-on-a-chip applications

The design and optimization of light-based analytical devices often require optical characterization of materials involved in their construction. With the aim of benefiting lab-on-a-chip applications, a transmission spectrometric method for determining refractive indices, n, of transparent solids is presented here. Angular dependence of the reflection coefficient between material-air interfaces constitutes the basis of the procedure. Firstly, the method is studied via simulation, using a theoretical algorithm that describes the light propagation through the sample slide, to assess the potentially attainable accuracy. Simulations also serve to specify the angles at which measurements should be taken. Secondly, a visible light source and an optical fiber spectrometer are used to perform measurements on three commonly used materials in optical lab-on-a-chip devices. A nonlinear regression subroutine fits experimental data to the proposed theoretical model and is used to obtain n. Because the attainable precision using this method of refractive index determination is dictated by the uncertainty in the transmission measurements, the precision (with 95% confidence) for mechanically rigid samples, namely glass and poly(methyl methacrylate) (PMMA), is higher than those estimated for the elastomer sample (in-house-molded poly(dimethylsiloxane) (PDMS)). At wavelengths with the highest signal-to-noise ratio for the spectrometer setup, the estimated refractive indices were 1.43+/-0.05 (580 nm) for PDMS, 1.54+/-0.02 (546 nm) for glass, and 1.485+/-0.005 (656 nm) for PMMA. Accurate refractive index estimations with an average precision equal to 0.01 refractive index units (RIU) were obtained for PMMA and glass samples, and an average precision of 0.09 RIU for the PDMS molded slide between 550 and 750 nm was obtained.     

Origin of crystallization-induced refractive index changes in photo-thermo-refractive glass

Photo-thermo-refractive (PTR) glass is a multi-component silicate that undergoes localized refractive index decrease after UV-exposure and thermal treatment for partial crystallization. Based on this refractive index change, high efficiency volume Bragg gratings have been developed in PTR glass and have been successfully used for laser beam control. However, despite the fact that this type of glass has been widely studied and used over the last 20 years, the origin of the refractive index change upon crystallization is poorly understood. In this paper, we introduce three possible mechanisms (the precipitation of nano-sized NaF crystals and the associated local chemical changes of the glass matrix, the volumetric changes due to relaxation, and the local residual stresses) for the refractive index decrement in PTR glass and estimate the partial refractive index change due to each mechanism. Refractive index measurements are compared with high temperature XRD experiments and a general approach for the simulation of the refractive index change in PTR glass is proposed. We show that among the studied variables the residual stresses surrounding the crystals are the main responsible for the local refractive index decrement in this glass.     

The structure and optical dispersion of the refractive index of tellurite glass

The structure and optical properties of a 80TeO₂-(20−x)Li₂O-xTiO₂ glass system where x = 0, 5, 10, and 15 mol% has been investigated using FTIR spectroscopy and Brewster angle measurements. The sample preparation, linear refractive index and density measurements, and infrared spectroscopic analysis are described. The refractive index and density of the studied tellurite glass samples increase when the amount of Ti in the glass is increased. The dispersion of the phase refractive index was analyzed using Wemple’s model. The dispersion energy E_d is significantly affected by the addition of Ti to TeO₂-based glass. The analysis of FTIR spectra indicate a Te coordination change that is in agreement with the increase of the Te coordination number determined from dispersion data using Wemple’s equation.     

Optical method for measuring optical rotation angle and refractive index of chiral solution

Based on the phenomena of Brewster's angle and the principles of common-path heterodyne interferometry, we present an optical method for measuring the optical rotation angle and the refractive index of a chiral solution simultaneously in one optical configuration. A heterodyne light beam and a circularly polarized heterodyne light beam are separately guided to project onto the interface of a semicircle glass and a chiral solution. One of the beams is transmitted through the solution, and the other is reflected near Brewster's angle at the interface. Then the two beams pass through polarization components respectively for interference. The phase differences of the two interference signals used to determine the rotation angle and the refractive index become very high with the proper azimuth angles of some polarization components, hence achieving an accurate rotational angle and a refractive index. The feasibility of the measuring method was demonstrated by our experimental results. This method should bear the merits of high accuracy, short sample medium length, and simpler operational endeavor.