SISAM interferometer for distance measurements

We measure short distances with a spectromètre interférentiel à sélection par l'amplitude de la modulation (SISAM) (interferential spectrometer by selection of amplitude modulation) interferometer that correlates optical fields. We present the method and the resolution of the system. A test with a Michelson interferometer shows SISAM's ability to detect phase change in one arm of the Michelson interferometer.     

DRM接收机射频前端芯片的频率规划设计

基于DRM标准,研究并设计了一种DRM广播接收机射频前端芯片的结构,该射频前端选用了上边注入、固定中频的二次正交混频低中频结构。经理论推导,给出了该结构的4种镜像抑制比（IRR）与相位误差或幅度误差的定量关系。经综合考虑镜像干扰、互调干扰、低频本振谐波干扰、寄生低频噪声等因素与中频频率的定量或定性关系,确定了系统频率规划。该结构中除射频滤波器外其它模块均为片上实现,继承了低中频结构的所有优点。理论分析与仿真结果表明,采用该频率规划的接收机射频前端完全满足DRM接收机射频前端的设计要求。此频率规划设计为射频前端芯片的电路级设计成功奠定了理论基础。     

Temperature Distributions in Piezoelectric Photothermal Spectroscopy

Piezoelectric photothermal spectroscopy is a method in which the stress and strain of a sample due to the absorption of electromagnetic radiation is detected by a piezoelectric transducer. The temperature distribution in the sample is the basis to obtain the theoretical amplitude and phase of photothermal piezoelectric spectra. In contrast to microphone detection, which needs only the temperature at one of the sample surfaces, in the piezoelectric one, it is necessary to know the spatial temperature distribution. The distributions given by Blonskij and by the modified interferential model of Malinski are applied. The influence of defect states in a volume and at the surfaces on the character of the amplitude and phase piezoelectric spectra is analyzed. The comparison of these approximate models and the two-layer one of Fernelius is presented.     

Efficiency of polarimetric z probing in optical multilayers

Numerical calculation is performed to validate the principles of a single optical technique devoted to real time probing or imaging of submultilayers within interferential coatings.     

光电干扰系统基于UML的C3I系统软件建模

将C^3I系统实时获取信息、传输信息、处理信息进行态势分析与估计,然后自动决策应用于光电干扰系统软件设计,能大幅度提高光电干扰系统的效能,从而提高战区C^3I系统的攻击与防卫效能。首先描述光电干扰系统的功能需求,利用C^4ISR与UML体系结构的高层处理过程提出UML建模的框架;接着应用UML遵循RUP的核心思想和基本原则对光电干扰系统软件进行了建模,逐步进行了需求收集、系统分析与系统设计,在每个过程均用一系列UML图来形象化地表示;最后提出了在建模过程中应注意的问题。利用已成为事实上标准并且符合人们思维习惯的UML进行系统建模,开发周期相对短,产品较丰富并且保证了系统开发和维护人员对系统的理解,系统分析、系统设计以及系统维护的一致性,更重要的是模型建立后可直接编程实现。     

利用空域采样相移干涉计量法测量微小位移

提出了一种利用空域采样实现相移干涉计量的新方法和实验演示装置。演示装置使用倾斜镜或阶梯镜作为相移器件,线阵CCD做为光学传感器。实验表明:此方法非常适用于测量快速变化的目标或动态过程,其测量精度与传统时域采样相移技术相当但具有更好的稳定性和更高的测量速度,而测量范围是离焦量的2倍。     

Realization of a radiometric head for measurements of ultraviolet total erythemal effective irradiance

An innovative sensor with a spectral response equivalent to the erythemal action curve for ultraviolet total effective irradiance measurements is presented. Optical and sensor components have been selected after the characterization of different samples. The design is based on an innovative interferential filter, which has been realized and tested. A first prototype has been assembled and characterized. Our measurements demonstrate the feasibility and potential of this instrument.     

Polychromatic Self-imaging

Abstract

The necessary condition for self-imaging in incoherent polychromatic light is derived from the McCutchen and central-slice theorems. Two types of self-imaging pupils are analysed: a pupil produced by a diffracting mask which gives self-images at positions depending on the wavelength, and an interferential pupil using a Fabry-Perot etalon which produces achromatic self-images. Experimental verifications are presented.     

Electron beam irradiation induced metastable phase in a Mg-9.8 wt％Sn alloy

Aberration-corrected scanning transmission electron microscopy has been used to study a novel metastable phase,designated as β"phase,induced to form by electron beam irradiation in a Mg-9.8 wt.％Sn alloy.This phase is spherical in three dimensions,having a DO19 structure with the lattice param-eters of a=0.642 nm,c=0.521 nm and space group of P63/mmc.Its chemical formula is Mg3Sn,like the β'metastable precipitate phase.The orientation relationship between the β"phase and the α-Mg matrix is such that[2(1)(1)0]β"//[2(1)(1)0]α and(0001)β"//(0001)α.Its formation involves solely the ordering of Sn atoms in the solid solution magnesium matrix.First-principles calculations indicate that the formation of the β"phase is energetically favored.     

固溶时效处理对TM60合金组织和力学性能的影响

通过对8型钛合金TM60进行不同制度的固溶时效处理,研究了各制度下其显微组织、相结构和力学性能的变化。研究结果表明：α相的含量和体积分数对合金性能有较大影响,固溶处理温度选择在700℃,时效处理温度应选择在400℃~450℃,β型钛合金TM60具有最佳的强塑性。     

Properties of optical transition radiation for charged particle inclined flight through a finite thick plate IX

In this paper the OTR angular distributions are considered in the general case of inclined particle incidence on a finite width plate with strong absorption. A sufficient increase of the OTR intensity in the case of grazing flight through a thin (as compared to λ) plate is shown to be caused by the Vavilov-Cherenkov radiation emitted from metal to vacuum. Attention is paid to peculiar interferential effects occurring in the OTR angular distributions in the plate case.     

Radiometric and signal-to-noise ratio properties of multiplex dispersive spectrometry

Recent theoretical investigations have shown important radiometric disadvantages of interferential multiplexing in Fourier transform spectrometry that apparently can be applied even to coded aperture spectrometers. We have reexamined the methods of noninterferential multiplexing in order to assess their signal-to-noise ratio (SNR) performance, relying on a theoretical modeling of the multiplexed signals. We are able to show that quite similar SNR and radiometric disadvantages affect multiplex dispersive spectrometry. The effect of noise on spectral estimations is discussed.     

除油液中烷基酚聚氧乙烯醚类表面活性剂的定量分析

利用紫外光谱法,对金属表面除油处理用除油液中的表面活性剂（OP－10）的定量分析进行了研究,分析了除油液中其他成分对OP－10测量的影响,讨论油污类型对OP－10测量的影响及消除方法。结果表明,测量数值准确度高,稳定,灵敏度也高,对除油液中表面活性剂的含量分析有重要的实用意义。     

双波长分光光度法连续测定锌镍合金镀液中Zn2+与Ni2+的含量

采用分光光度计和比色管,研究了以XO为显色剂并用双波长分光光度法测定电镀Zn-Ni合金溶液中的Zn^2 与Ni^2 含量的方法,分析了测量波长与参比波长的选择、溶液酸度与显色条件、测量的线性范围以及有机络合剂和Fe^3 等干扰因素的排除对测量结果的影响。实验结果证明,该方法是可行的,能连续测定镀液中的Zn^2 与Ni^2＋的含量。     

Vibration transducer using an optical cavity comprising birefringent mirrors

We have developed an optical-cavity system comprising birefringent mirrors for a vibration transducer. To obtain a dispersive-shape signal necessary for reading out the information of mirror vibration, we measure the polarization change of the cavity transmission light caused by the natural birefringence appearing on interferential mirrors; this effect is enhanced by the cavity resonance. Since there are no additional polarization-changing elements inside the cavity, we can achieve the high finesse that is indispensable for a highly sensitive vibration measurement. The principle and an experimental demonstration of the system are reported here.     

甲醛快速测定仪测试性能研究

通过考察甲醛快速测定仪分析方法的线性范围、灵敏度、准确度、精密度及方法扩展不确定度等技术指标，研究环境因素如空气中干扰物、温度、湿度、风速等的影响，比较甲醛快速测定仪与国家标准方法在测试甲醛标准气体或室内空气测试结果的差异。结果证实甲醛快速测定仪分析方法的特性优异、测试结果受环境因素影响小与国家标准方法测试结果相关性好，适合测试室内空气中的甲醛气体。     

基于主动照射式的人脸定位

对于人脸定位问题,国内外的研究方法概括起来有基于特征和基于图像两种.本文提出了一种主动照射的人脸定位算法.该算法采用主动结构光照射的方法,同时使用积分投影的结果来分析人脸的几何结构,最后利用鼻子的特征定位人脸.从而做到在背景比较复杂、干扰物体(如杯子,水桶等等)比较多的情况下快速定位人脸中心位置,对摄像头采集到的最大分辨率640×480的有效图像的实时定位速度达到10帧/秒.打破了常规要求图像背景相对简单的缺陷, 从而可以在复杂背景条件下对人脸进行定位.     

Three-dimensional simulation of diffraction and absorption losses in all-fiber multilayer filters

A rigorous modal three-dimensional calculation method is used to analyze the diffraction and absorption losses in Fabry-Perot (FP) multilayer interferential filters between both single-mode input and output fibers. With an ordinary personal computer, this method affords accurate calculation of the absorption losses and the diffraction into the cladding modes of both fibers as well as the reflectance into the input fiber. The calculation results show that absorption losses and diffraction are troublesome for high-finesse FP filters.     

基于波长移相的改进加权多步算法

在斐索干涉仪中测量光学平板受到多面反射光束的影响,而波长移相干涉技术是通过光源波长的改变来实现干涉信号的移相,原理上可以实现各个干涉信号的分离,在算法上要求能对多次谐波进行较好的抑制,加权多步移相算法可以实现这样的目的.笔者提出了加权多步移相算法的改进算法,可以提高算法对误差的抑制能力,最后用实验验证了改进算法的有效性.