单光子探测器量子效率的绝对自身标定方法

提出一种单光子探测器量子效率的绝对自身标定方案，利用光参量下转换过程中产生的光子对在时间上的相关性，先将参量光束分为两路，然后引入相对延时，使同时产生的孪生光子先后进入单光子探测器，然后将探测器之后的电路分为三路，其中一路直接进入计数器得到探测器所探测到的光子的总计数率，另两路用电路方法引入和光路相当的相对延时，经符合电路后进入计数器，得到前后到达探测器的光子对之间的符合计数率.这样，从符合计数率与总光子计数率之比即可在不需要任何其他探测器或者参照标准的情况下获得探测器的量子效率.文中给出两种方案，分别适     

A Water-Stable Lanthanide Coordination Polymer as Multicenter Platform for Ratiometric Luminescent Sensing Antibiotics

As a hot topic of global concern, the distinguishing and detecting of antibiotic pollution is crucial owing to its adverse effect on ecosystems and human health stemming from excessive use and poor management. Herein, a water-stable lanthanide coordination polymer sensor (Dy-TCPB) with multiple emitting centers is prepared. The versatile Dy-TCPB can conveniently differentiate various antibiotics, and displays a self-calibration luminescent response to nitrofurazone (NFZ) and furazolidone (FZD). Each antibiotic exhibits notable correlation to a unique combination of the two ligand-to-Dy ion emission intensity ratios, enabling two-dimensional fingerprint recognition. Furthermore, the novel self-calibration sensor demonstrates effective recognition of NFZ and FZD with excellent sensitivity and selectivity, and detection limits as low as 0.0476 and 0.0482 μm for NFZ and FZD, respectively. The synthetic approach for the fabrication of a singular coordination polymer exhibiting multiple emissions provides a promising strategy for the development of facile and effective ratiometric sensors.     

彩虹自标定方法对混合喷雾比例的原位测量

传统彩虹测量技术标定复杂、精度可重复性差且难以适应密闭空间。一种基于多彩虹谱线自标定方法,可省去原有的标定系统装置,将标定过程内化于对彩虹信号的处理,以水为例的测量偏差仅为0.13%。将该技术应用于混合喷雾液滴组分浓度测量中,探究并优化了参与混合的两种液体组分的方案。实验采用60%乙醇-水混合喷雾,原位测量了混合喷雾场多点组分浓度,测量结果差别可以控制在0.5%以内,表明该方法技术在相关领域的应用潜力。     

一种自校准光纤珐珀动态应变检测系统的实验研究

针对工程中光纤珐珀传感器的工作点容易偏离线性工作区而使解调系统无法正常工作的实际问题,设计了一种可实现自动校准工作点的动态应变检测系统。该系统利用数字信号处理器控制可调珐珀滤波器自动输出波长满足工作点要求的窄带光,同时还通过软件校准的办法消除了因光源的不稳定、系统老化等缓变因素引起的信号波动对测量结果的影响。实验结果表明该动态应变检测系统能完成工作点自动校准,并且在500με范围内线性度可达99．79％,实验分辨率约为±0．5με。     

基于双轴旋转惯导的激光陀螺仪与g有关偏置自标定法

标定激光陀螺仪与g有关偏置可以进一步提高双轴旋转惯导的定位精度。在传统的六位置标定方法上增加四个倾斜的位置,形成一套十位置自标定算法。该算法不仅可以标定惯性器件的常值偏置,比例因数误差和失准角,还能标定陀螺仪的与g有关偏置。静态试验表明,在标定和补偿了陀螺仪与g有关偏置项后,经纬度误差(尤其是经度误差)随着时间的变化量明显减小。与传统的六位置法相比,经度误差随着时间发散速度明显降低。该自标定法在静态时至少可以提高50%的系统精度。     

混合式光纤陀螺惯导系统在线自主标定

混合式光纤陀螺惯导系统IMU的安装误差、光纤陀螺的漂移及标度因数等参数会随着时间发生变化,对系统误差产生影响,使系统在使用一段时间之后精度发生变化,因而需要重新标定。在混合式系统中,通过台体旋转调制,惯性元件常值漂移误差对系统的影响得到抑制,但安装误差和标度因数误差对系统的影响无法得到完全调制,这些误差会与地速及旋转角速率耦合,引起锯齿形速度误差,降低了系统的各项性能。针对混合式惯导系统,建立了IMU误差模型,设计出一种在线自主标定方法,并进行了可观性分析。该方法采用"速度+位置"匹配,对惯导系统30项相关误差项进行在线标定。系统实验结果表明,系统级在线标定参数较分立式标定参数在导航定位精度上提高了半个数量级。     

Online self-calibration for mobile vision based on laser imaging and computer algorithms

A self-calibration technique for mobile three-dimensional vision is presented. This technique determines the vision parameters during the vision task based on computer algorithms and image processing. The three-dimensional vision is performed by a Bezier network based on laser line projection. This network provides the data to perform the online self-calibration when the vision system is modified. Here, the changes of the extrinsic and intrinsic parameters are determined. The structure of the network is performed by the line shifting provided by the surface depth. From this structure, the data for the initial calibration and online self-calibration are deduced. In this manner, the calibrated references and physical measurements are avoided to perform the online self-calibration. Therefore, calibration limitations caused by online modifications are overcome to perform the mobile vision. Thus, the proposed self-calibration improves the accuracy and performance of the mobile vision. It is because online data of calibrated references are not passed to the vision system. This procedure represents a contribution in the field of the online recalibration, which is performed based on calibrated references. To elucidate this contribution, an evaluation is performed based on the self-calibration methods, which are reported in the recent years. Also, the time processing is described.     

基于声矢量水听器阵列误差的自校正算法

对声矢量水听器阵列的各类误差进行了分类,推导了各类误差对阵列信号模型的影响因子,通过Monte Carlo实验分析对比了各类误差对阵列DOA估计性能的影响,然后将方向性误差和位置误差归结为幅度误差和相位误差,在传统声压阵列误差校正模型和算法的基础上,得到矢量阵列误差自校正的优化模型及自校正算法,最后,通过仿真实验和外场实验的数据处理表明,自校正算法具有良好的参数估计性能,具有一定的工程实用性.     

激光陀螺捷联惯导系统参数稳定性与外场自标定

惯导系统参数稳定性是决定系统精度的重要因素。基于激光陀螺捷联惯导系统参数稳定性统计分析,建立了适合激光陀螺捷联惯导系统外场自标定的加速度计组件误差参数模型。以惯性组合转动后重新调平的水平姿态修正量以及静态下重力测量误差为观测量,不依赖外界方向姿态转角等基准信息,实现了加速度计组件主要误差参数在外场条件下的自标定,并给出了标定参数的修正方法。实验表明,常温下加速度计组件的标定参数发生明显变化,采用外场标定方法可对其进行修正,相应的水平姿态最大误差由65″减小到10″。该方法标定精度好,标定时间短,操作简便,且对基座不稳造成的瞬时姿态小扰动影响有抑制能力。     

Self-calibration wavelength modulation spectroscopy for acetylene detection based on tunable diode laser absorption spectroscopy

The expressions of the second harmonic(2f) signal are derived on the basis of absorption spectral and lock-in theories.A parametric study indicates that the phase shift between the intensity and wavelength modulation makes a great contribution to the 2f signal.A self-calibration wavelength modulation spectroscopy(WMS) method based on tunable diode laser absorption spectroscopy(TOLAS) is applied,combining the advantages of ambient pressure,temperature suppression,and phase-shift influences elimination.Species concentration is retrieved simultaneously from selected 2f signal pairs of measured and reference WMS-2f spectra.The absorption line of acetylene(C_2H_2) at 1530.36 nm near-infrared is selected to detect C_2H_2 concentrations in the range of 0-400 ppmv.System sensitivity,detection precision and limit are markedly improved,demonstrating that the self-calibration method has better detecting performance than the conventional WMS.