利用硅压阻式力敏传感器测定液体膨胀系数

根据液体膨胀系数与温度、密度相关的性质,利用硅压阻式力敏传感器设计了测定液体膨胀系数实验.通过测量不同温度下的输出电压,计算液体的膨胀系数,实现了对非电学量力的电测.     

多元有机混合液声速特性与非线性声参量B/A的数值计算

根据Jacobson的液体分子自由程理论和液体声速与分子自由程的关系,推导出多元有机混合液声速的温度系数、压力系数和非线性声参量B/A的计算公式,并根据组成多元有机混合液各组分特性参量(密度、自由程、非线性声参量B/A、等压膨胀系数、等温压缩系数等),利用给出的公式对声速的温度系数、压力系数、非线性声参量B/A进行了数值计算,并将计算结果与实验结果进行了比较.     

薄膜滤光片的光学稳定性研究

薄膜滤光片中心波长的稳定性是非常重要的参量.这不仅取决于膜层的聚集密度,而且与薄膜材料和基板的折射率温度系数及线性膨胀系数有着紧密的关系.本文根据滤光片的实验参量,分析计算了它们对滤光片中心波长漂移影响的大小,并提出了改善稳定性的途径.     

利用光子晶体测量透明液体折射率

设计了用反Opal结构光子晶体测量透明液体折射率的实验.根据布拉格公式推导了用反Opal光子晶体测量透明液体折射率的公式.利用紫外-可见分光光度计分别测得光子晶体处于空气和透明液体中的透射谱,由透射谱分别确定光子晶体处于2种介质中的禁带中心波长,将中心波长代入测量公式即可得到透明液体折射率.实验测量了水和甘油的折射率,得到了与公认值相吻合的结果.     

方形容器测量液体折射率和色散率

介绍了一种利用激光测液体折射率的简易方法.通过测量光线穿过垂直棱镜角后发生全反射时的入射临界角,进而求出液体的折射率.再利用折射率与临界角的关系,结合科希经验公式求出液体色散率.     

用光拍法研究葡萄糖溶液密度和折射率的关系

实验根据葡萄糖溶液浓度不同对折射率的影响,采用光拍法测定液体的折射率,计算出液体的密度,并采用最小二乘法进行线性拟合,最后发现葡萄糖溶液的密度和折射率几乎呈线性关系.     

“干涉逼近法”测量液体折射率

提出了一种高精度测量液体折射率的新方法一“干涉逼近法”.这种方法可以在测量过程中监视被测液体温度不均匀性给测量带来的误差.由于受温度测量的限制,其测量液体折射率的不确定度在1×10~(-6)到4×10~(-5)(2σ)之间,具体值取决于液体折射率的温度系数.     

波分复用薄膜带通滤光片的中心波长温度稳定性

讨论了影响波分复用薄膜滤光片中心波长漂移的因素 ,着重分析了滤光片的温度稳定性。根据实验结果 ,借助于高桥模型 ,分析计算了滤光片的折射率温度系数、线膨胀系数和泊松比以及它们对温度漂移的影响。得到了Ta2 O5/SiO2 滤光片薄膜的折射率温度系数、线膨胀系数、泊松比分别为 1× 10 -5℃-1,5× 10 -7℃-1和 0 12 ,指出了这三个参量是影响温度稳定性最重要的因素 ,特别是薄膜的折射率温度系数。对特定的基板热膨胀系数 ,通过调节滤光片的干涉级次和间隔层材料 ,可望得到零温度漂移的稳定滤光片。     

测量液体折射率随温度的变化

本文根据温度变化对液体折射率的影响，通过实验测量了液体折射率随温度的变化，从而获得对折射率的更全面了解。     

透明液体质量分数与折射率关系的居家实验

基于折射定律和光杠杆原理设计了透明液体质量分数与折射率关系研究的居家实验,通过多边形容器的2个面折射,采用光杠杆原理将因液体质量分数变化而引起的折射光线偏移量放大,再利用折射定律和光杠杆的几何关系得到液体折射率和光线偏移量之间的关系.以NaCl溶液为例,分别用方形容器和三角形容器进行了测量,实验结果表明液体的质量分数与折射率呈线性关系,与经验公式吻合,且方形容器的测量精度更高.     

液体折射率随温度改变的研究

利用阿贝折射仪配合水浴缸控温对液体折射率进行测量。测量液体包括金龙鱼调和油、金龙鱼玉米油、福临门调和油以及过期的金龙鱼调和油。根据数据分析得到了所有实验材料折射率随温度变化规律、四种油类材料的折射率间的相对大小关系、四种油类材料的折射率随温度升高而降低的情况对比等实验结论。并结合相关理论分析现象产生的原因。     

Optical properties of a liquid crystal with small ordinary and extraordinary refractive indices and small optical anisotropy

Optical properties of a nematic liquid crystal with small refractive index and small birefringence were studied. The ordinary and extraordinary refractive indices and birefringence were measured as functions of temperature by using an Abbe refractometer and wedge nematic cells. From values of these indices the nematic orientational order parameter was calculated by using several methods and corresponding mathematical models. Kuczyński et al. method was found to be suitable for determining the order parameter also for materials featuring small ordinary refractive index, with unknown density.     

Experimental determination of superheated liquid density by the optical fiber method

An experimental approach to determination of the density of liquid superheated with respect to the liquid-vapor equilibrium temperature, including the range of high degrees of superheating, is developed. The approach is based on application of an optical fiber method combined with a pure bubble chamber. Performance of the method for investigation of the refractive index and density for superheated liquids as functions of temperature and pressure is illustrated in experiments with n-hexane as a reference substance for thermophysical measurements. The relative density measurements are performed with a resolution up to 10^?4 at a characteristic time of 1 ms. For absolute measurements, the setup should be calibrated by the known data on the liquid density for the saturation line.     

Liquid refractive index sensor with three-cascaded microchannels in single-mode fiber fabricated by femtosecond laser-induced water breakdown

Liquid refractive index sensor with three-cascaded microchannels in single-mode fiber was fabricated by femtosecond laser-induced water breakdown. When the liquid is filled in three microchannels across the fiber core, the transmission spectrum of the sensor shows interference peaks. The refractive index of liquid can be sensed accurately based on both the wavelength shift and loss change of interference peaks. The refractive index sensitivities of wavelength shift and loss change reach to as high as ?2,406.1 nm/RIU and ?156.8 dB/RIU, respectively. The sensor is insensitive to the refractive index change of liquid caused by environmental temperature. It can be used for liquid refractive index sensing with high sensitivity, especially for water pollution monitoring.     

Investigation of thermal influence on the bandgap properties of liquid-crystal photonic crystal fibers

We have analyzed the thermal influence on the bandgap properties of liquid-crystal photonic crystal fibers. The bandgap parameters which affect the transmission conditions have been investigated. It is observed that the photonic bandgap can be thermally tuned, i.e. the red or blue shift of the bandgap results from the temperature dependence of the refractive index of the liquid crystal. For the planar alignment of liquid-crystal filled cladding, the ordinary refractive index plays a major role in determining the bandgap properties; the extraordinary refractive index comes into influence while the ordinary refractive index is relatively constant of temperature. The analyses agree well with the experiments results.     

Investigation of first and second ionization on optical properties of atmospheric plasmas

In this paper, the relation between refractive index and other atmospheric plasma properties including electron, ion and molecule number densities and temperature are calculated. Considering the first and second ionization and the atmospheric air composition, the temperature dependence of the atmospheric plasma on refractive index is obtained by Saha equation. Also, in contrast to conventional models for evaluating electron number density by optical techniques, in which the refractive index of plasmas is approximately assumed equal to electron refractive index, this work is proposed for accurate and absolute measurement of electron density profile and determination of plasma region.     

Simultaneous Measurement of Temperature and Refractive Index of Liquid Using Cladding-Etched Double-Core Fiber Bragg Grating

Abstract

This study proposed and demonstrated a fiber Bragg grating sensor for simultaneous detection of the temperature and refractive index of a liquid. The fiber Bragg grating is composed of three index layers: an inner core, an outer core, and a cladding. The cladding was etched for evanescent wave coupling between the outer core mode and an external liquid. The Bragg wavelength of the inner core mode is used for obtaining temperature data, while the refractive index for the liquid was determined by using the difference between the Bragg wavelength of the inner core mode and that of outer core mode.     

Tunable Dielectric Metasurfaces Based on the Variation of the Refractive Index of the Environment

A dielectric metasurface at the variation of the refractive index of the environment has been numerically simulated. The optical response of the metasurface contacting both a homogeneous medium with different refractive indices and a liquid crystal controlled by the temperature and applied electric field has been considered. The results can be used to produce optical devices for various aims. Numerical simulations have been performed for the parameters of the liquid crystal E7 widely used in industry.     

槽沉法制备球透镜

根据光通信耦合器件发展的趋势,研制了一种新型光学玻璃。依据在表面张力的作用下的液滴冷凝,得到透明玻璃微球理论[1],首次使用槽沉法来制备球透镜。结果表明:玻璃的最佳退火温度为570℃、折射率为1.5198、透过率大于90%。得到直径为0.8mm的球透镜最佳成球温度为1250℃、折射率为1.5190光谱透过率大于90%。