折射率

Through the further research to the theory of the high-accuracy achromatism phase retarders,the changing curve of retardation under the different center refracting rate and different precision are obtained.

通过对高精度消色差相位延迟器理论设计的再研究，分别得到在不同中心折射率下和不同延迟精度下，延迟量随折射率改变的变化曲线。

The result indicates that in the designed center of the wavelength, the retarder is not only confined within the low dispersive medium, but high-index material with higher dispersion can also obtain good achromatism, and at the same time the bigger angle of total reflection can improve achromatism of the phase retarder.

从全内反射相变方程出发，以菲涅尔菱体为例，分析了消色差相位延迟器的相位延迟量随折射率变化的光谱特性，结果表明：在所设计的中心波长处，延迟器件不仅仅局限于选择低色散的材料，色散较大的高折射率材料制作的延迟器件也可以具有良好的消色差性，且较大的全内反射角有利于改善延迟器件的消色差性。

As a result, if the iridescence is produced by thin-film interference, not only the thickness of lamellar structure must be defined within a certain nanometer, but also the refractive index need to be different between lamellar structure. In other words, the chemical composition, refractive index and thickness of exsolution lamellae need form to trinity, such as labradorite, albite, andradite and orthoamphibole. If the iridescent color is produced by grating-diffraction, the lamellar structure just needs to be arrayed regularly, the spacing of the edges of lamellar structure needs to be regular and narrow, but not necessarily within the range of the wavelength of visible light, such as shell of abalone, pearl and opal.

薄膜干涉式晕彩不仅要求宝石内部结构层的厚度必须在一定的纳米范围内，而且结构层内部的折射率也必须有所差别，也即，当结构层由两相组分出溶而成，其化学成分、折射率和结构层厚度形成三位一体时，符合薄膜干涉式晕彩，如拉长石、钠长石、石榴石和角闪石；而光栅式衍射晕彩则仅要求结构层排列规则，边缘狭窄但不需要窄到可见光波长范围内，能使入射光的振幅或位相，或两者同时产生周期性空间调制的结构即可，如鲍贝壳、珍珠和欧泊。

Based on the method of minimum deviation angle, man can obtain the accuracy of measuring refractive index of glass at 3×10-6 with fine apparatus for measuring angle, but the classical princip1e formula quote...

计算表明，用经典公式计算标准试样折射率虽然对光学系统象差影响很小，但作为折射率基准测量，这样大的原理公式误差是不允许的。

In terms of the refraction angle measured at the metal/air interface, we quantitatively obtained the relationship between the value of pseudo refractive index and incidence angle.

改进的途径是设法寻找到负折射率材料，与正折射率材料匹配在一起，预期可形成完美光学透镜。

The first liquid crystal material has birefraction index approximately equal to one half of that of the second liquid crystal material.

其中，第一液晶材料层的双折射率约略等于第二液晶材料层的双折射率的一半。

Because the vapor and water have different refractive indexes, the vapor-to-water ratio can be deduced from the response characteristic of refractive index of two-phase flow.

由于干蒸气和水的折射率不同，汽液的比例可以从汽液两相流的折射率响应特性反映出来。

The theoretic results show that retroreflective intensity increases gradually with accretion of refractive index when refractive index is less than two, but decreases when refractive index is great than two.

研究结果表明，折射率增大，折射率小于2时，回向反射性能逐渐增强，相反，在折射率大于2时，回向反射性能减弱；反射层面积的大小会影响入射光线的完整回向反射过程；最后定义了有效回向反射角度，并给出了玻璃微珠在激光照射下的二维回向反射光照度分布。

Analytical formulae are presented for the first time to describe the shift in the resonance wavelength of LPG in response to etching of the fiber cladding or a change in the external refractive index. The accuracy of the formula is confirmed by comparision with numerical simulations and experimental results. We demonstrated that the resonance wavelengths of an etched LPG are more sensitive refractive index than those of an unetched grating. The bending properties of long period fiber grating written in different type fiber are studied experimentally. The transmission peaks and the central wavelength of LPG change with the bending of the fiber. A new peak appears at the shorter wavelength when the fiber is being bent. The changes of the peaks are different for different photosensitive fiber. Those properties have broad application foreground in fiber sensors and tunable filters.

分别从理论和实验上对长周期光栅的折射率特性以及光纤包层半径对长周期光栅特性的影响进行了研究，首次给出了描述光纤包层半径腐蚀和外界折射率改变与长周期光栅共振波长关系的理论表达式，实验与理论和数据模拟的结果很好符合，利用腐蚀光纤包层的方法可以有效地提高LPG的折射率灵敏度；对不同光纤中写入的长周期光栅的弯曲特性进行了实验研究，LPG的透射峰形状及其中心波长随光纤弯曲而发生变化，并且随着弯曲将在短波方向出现新的透射峰，其透射峰的变化规律因所用光敏光纤的不同而不同，这一特性在光纤传感和可调谐滤波器方面有重要的应用前景。

The model of photon-induced refractive index change based on GaAs materials is presented briefly, then the model based on GaAs/AIGaAs quantum wells materials is deeply analyzed by treating the effects of photon-excited carriers self-consistently. Furthermore, the propagation characteristics of multi-quantum well waveguide is invested, and the low-loss multi-quantum well rib waveguide deeply etched is also designed by using the spectral index method.

在简要分析了基于GaAs材料的光致折射率模型的基础上，通过自洽的方法，重点研究了基于GaAs/AlGaAs多量子阱材料的光致折射率模型；其次分析了量子阱波导传输特性，利用谱折射率法设计低损耗的深刻蚀脊形量子阱波导。

Cynanchum Lingtai apricot production in the average weight 65 grams, the brightly-colored fruit, juicy rich, sweet-sour taste, sweet from the nucleolus, when the late Qing Dynasty famous Shaanxi, Gansu provinces, the Qing imperial court Tongzhi tribute for years.

灵台生产的牛心杏平均单果重65克，果实色泽鲜艳，汁多味浓，甜酸适口，离核仁甜，清末时就驰名陕、甘两省，清同治年间曾为朝廷贡品。

Chenopodium album,Solanum nigrum, and Amaranthus retroflexus were very susceptible to the herbicides. Polygonum persicaria and Abutilon theophrasti were relatively less susceptible to the herbicides, and Lycopersicon esculentum was not susceptible to it. The relationship between reduction rates of weed biomass and PPM values of weed leaves 2,4, and 6 days after treatment was established.

供试的6种杂草对该混剂的敏感性存在显著差异：红心藜Chenopodium album、龙葵Solanum nigrum和反枝苋Amaranthus retroflexus对该混剂最敏感，ED90值分别为47.65、71.67和29.17g/hm2；春蓼Polygonum persicaria和苘麻Abutilon theophrasti敏感，ED90值分别为96.91、114.20g/hm2；而番茄不敏感。