利用Talbot效应测定光的波长

作为Ｔａｌｂｏｔ效应的一种新应用，本文提出一种测定光波长的方法；该方法以Ｔａｌｂｏｔ效应为基础，借助于叠栅条纹技术来判断Ｔａｌｂｏｔ像面的位置。文中给出了实验结果及讨论     

Talbot像对谱面的对称性分析及焦距测量

分析了光栅的泰伯（Ｔａｌｂｏｔ）像和透镜焦面的关系，提出了Ｔａｌｂｏｔ像对谱面的对称性原理。并将其用于透镜焦距的测量，方法简单，精度高。     

用莫尔计算机层析技术诊断三维电弧温度场

结合光栅Ｔａｌｂｏｔ效应和莫尔技术，利用有限角计算机层析算法，借助电弧等离子体物理方程，对自由电弧三维温度场进行了诊断研究。     

晶体双折射测量的干涉条纹重迭法

本文介绍用干涉条纹的重迭与否测量晶体双折射。作者用干涉条纹取代光栅的Ｔａｌｂｏｔ像，主要优点是条纹的对比度好。     

泰伯效应的共轭现象

介绍了观察泰伯（Ｔａｌｂｏｔ）像的共轭虚像的实验原理及方法，并给出实验结果及扼要的理论解释，作者首次提出可把泰伯自成像公式的ｍ值扩展的负值。     

一种测量透镜焦距的方法

一种测量透镜焦距的方法王成，武晓东（中科院长春光机所，国家光学机械质量检测中心１３００２２）一、理论分析透镜的焦距是透镜的重要参数之一，通常是采用几何光学的方法进行测量，本文采用一种波动光学的方法——Ｔａｌｂｏｔ方法进行测量，测量精度较高，且使用方便...     

一种测量光栅常数的新方法

一种测量光栅常数的新方法华文深（华南理工大学应用物理系广州５１０６４１）一、测量原理如图１所示，当用点光源或线光源产生的发散光束照射光栅时，将产生Ｔａｌｂｏｔ效应［１－３］．即在某些位置上将得到光栅的衍射自成像，这些像相当于光栅的几何投影的放大像，而...     

基于泰伯效应的高斯光束尺寸测量

光栅用在高斯光束参数测量中的突出优点是方法简单，成本较低，全息光栅由于其制备容易，无周期误差而比一般光栅具有更多的优点。在用光栅进行光斑测量的实验中，观察到由全息光栅引起的泰伯（Ｔａｌｂｏｔ）效应携带有关光斑参数的有用信息，本文提出了一种基于泰伯效应的测量方法，只需测定条纹间隔就能确定高斯光束尺寸，因此降低了对光源或光栅定位精度，电路和光源稳定性的要求，文中聚焦高斯光束照明全息光栅时光场分布，及其     

基于莫尔理论的双波长全息干涉术分析

当用双波长全息干涉术通过单次曝光法或双曝光法对物体进行测量时 ,其效果相当于用一个等效波长λeq=λ1 λ2 /|λ1 -λ2 |对物体进行测量 ,扩大了测量波长的可选范围。采用莫尔理论从一个全新的角度对双波长全息干涉术的基本原理进行了分析和探讨 ,不仅揭示出了二者之间存在着的必然内在联系 ,而且还进一步证明了双波长全息干涉术的准确性和可行性 ,从而扩展了双波长全息干涉术的应用领域     

原子、分子以及电荷的原子力显微术操纵及其应用

原子力显微术在原子级分辨表征、化学键识别、探测电荷密度分布等领域都有重要的应用.本文在介绍原子力显微术基本工作原理的基础上,着重介绍其在室温原子操纵、对原子/分子操纵过程的表征、以及绝缘基底上的电荷操纵三个方面的工作进展.主要内容有:1)原子力显微术的成像原理及其对典型分子的化学键分辨表征; 2)原子力显微术在室温下的力学操纵和原子识别能力; 3)用原子力显微术操纵分子表面异构或吸附构型变化并表征该过程中的相互作用力; 4)在绝缘基底上通过原子力显微术对单分子及多分子的电荷操纵.原子力显微术操纵在这些领域内的工作拓展了扫描隧道显微镜在原子/分子操纵方面的工作范围,为理解并精确控制操纵过程及构造纳米尺度器件提供了新的思路.     

Single-beam self-referenced phase-sensitive surface plasmon resonance sensor with high detection resolution

A versatile and low-cost single-beam self-referenced phase-sensitive surface plasmon resonance(SPR)sensing system with ultra-high resolution performance is presented.The system exhibits a root-mean-square phase fluctuation of ±0.0028.over a period of 45 min.i.e.a resolution of±5.2×10-9 refractive index units.The enhanced performance has been achieved through the incorporation of three design elements:a true single-beam configuration enabling complete self-referencing so that only the phase change associated with SPR gets detected,a differential measurement scheme to eliminate spurious signals not related to the sensor response,and the elimination of retardation drifts by incorporating temperature stabilization in the liquid crystal phase modulato .Our design should bring the detection sensitivity of non-labeling SPR biosensing closer to that achievable by conventional fluorescence-based techniques.     

Effect ofγ-radiation on the spectral luminescence characteristics of impure cadmium tungstate crystals

Results of a study of the effect of γ-radiation on the spectral luminescence properties of cadmium tungstate crystals doped with silver, bismuth, and molybdenum cations are presented. Spectral characteristics of the nondnnnoped crystals are briefly described. Absorption and photo and X-ray luminescence spectra of the crystals taken before and after exposure to γ-radiation (5.5·10⁴ Gy) are compared. It is found that the spectral characteristics of the crystals doped with silver, bismuth, and molybdenum cations do not change markedly after the exposure. The relation between the type of impurity-induced defects, individual characteristics of the impurity cations, and the character of the effect of γ-radiation on the spectral luminescence properties of impure crystals is analyzed (preliminarily). Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 1, pp. 55–60, January–February, 1997.     

Cavitation in trees

Sap is transported under tension (i.e. negative pressure) in trees, according to the tension-cohesion theory. Since water is physically instable under negative pressure, a risk of cavitation is possible. Techniques have been developed during the past two decennia to study cavitation in trees. Trees appear remarkably immune to cavitation events. Cavities form only when extreme water stresses occur or when sap freezes. Nucleation is heterogeneous in trees, presumably caused by the aspiration of air bubbles through conduit walls. Threshold xylem pressures for cavitation vary greatly between species, in concordance with the great functional and ecological diversity of trees. To cite this article: H. Cochard, C. R. Physique 7 (2006).     

A stereo matching algorithm using multi-peak candidate matches and geometric constraints

Gray cross correlation matching technique is adopted to extract candidate matches with gray cross correla- tion coefficients less than some certain range of maximal correlation coefficient called multi-peak candidate matches. Multi-peak candidates are extracted corresponding to three closest feature points at first. The corresponding multi-peak candidate matches are used to construct the model polygon. Correspondence is determined based on the local geometric relations between the three feature points and the multi-peak candidates. The disparity test and the global consistency checkout are applied to eliminate the remaining ambiguous matches that are not removed by the local geometric relational test. Experimental results show that the proposed algorithm is feasible and accurate.     

Optical Pulse Compression Schemes That Use Nonlinear Bragg Gratings

Nonlinear optical pulse compression of picosecond pulses typically requires long lengths of optical fiber and multiple components. Periodic structures, such as fiber Bragg gratings, are highly dispersive at wavelengths outside of the photonic bandgap. This implies that such gratings can be used as very short all-fiber compressors. In this paper a number of such compression schemes are reviewed involving uniform and nonuniform fiber Bragg gratings, relying on both soliton and nonsoliton compression principles. Experimental results supporting the corresponding underlying theory are also presented. Finally, an extension of one of the compression schemes is shown, which allows the generation of adjustable high-repetition rate soliton trains.     

Conductively cooled all-solid-state zigzag slab laser

A diode pumped, Q-switched Nd：YAG zigzag slab laser is developed using passive conduction cooling. Flat-flat and unstable resonators are adopted in this experiment. The 150-mJ multi-mode and 100-mJ single-mode laser outputs with pulse width of 10 ns are achieved, corresponding to optical efficiencies of 19% and 13%, respectively. The experimental result demonstrates that the laser has the property of compact structure, high efficiency, reliability, and high beam quality. The design of laser has a potential application in space environment.     

The nature of empirical constants in the equation relating the frequency of the stretching vibration of oh-groups to parameters of the [MO n ]-polyhedrons coordinating these groups

Institute of Physicoorganic Chemistry, Academy of Sciences of Belarus, 220603, Minsk, Ul. Surganova, 13, Belarus. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 62, No. 1, pp. 104–107, January–February, 1995.     

Quantitative analysis results of CE-1 X-ray fluorescence spectrometer ground base experiment

As the nearest celestial body to the earth, the moon has become a hot spot again in astronomy field recently. The element analysis is a much important subject in many lunar projects. Remote X-ray spectrometry plays an important role in the geochemical exploration of the solar bodies. Because of th equasi-vacuum atmosphere on the moon, which has no absorption of X-ray, the X-ray fluorescence analysis is an effective way to determine the elemental abundance of lunar surface. The CE-1 X-ray fluorescence spectrometer (CE-1/XFS) aims to map the major elemental compositions on the lunar surface. This paper describes a method for quantitative analysis of elemental compositions. A series of ground base experiments are done to examine the capability of XFS. The obtained results, which show a reasonable agreement with the certified values at a 30% uncertainty level for major elements, are presented.     

A new tuning procedure for the DTL RF field pattern

The DTL tank is a multi-cell cavity.In a fabricated tank,the measured average axial field E0 for each cell may obviously deviate from the designed value.It is generally thought the deviation is due to the errors in fabrication and assembly.But it is not always true.In this paper,it is shown that the deviation may already exist before fabrication in some cases.It is partly due to the imperfection of the current design procedures.A new design method is introduced to reduce the deviation in the design stage.     

Effect of oxygen on the optical properties of ZnSe in the region of 0.44–20 μm

Moscow Power Engineering Institute, 14, Krasnokazarmennaya Str., Moscow, GSP, 105835, Russia. Translated from Zhurnal Prikladnois Spektroskopii, Vol. 63, No. 4, pp. 646–651, July–August, 1996.