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1 Introduction Opticalfibergratingsensors(FGSs)havegeneratedgreatinterestinrecentyearsbecauseoftheirpotentialuseinwiderangeofapplications,particularlyinmonitoringthestructuralintegrityofbuildings,bridgesandadvancedcompositematerials.However,mostFGSsare… 相似文献
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为验证光轴指向误差对光学姿态测量精度的影响程度,并为后续实况类设备实现姿态测量提供理论依据,以中轴线法为依据,对算法步骤进行拆分,并对光轴指向误差的影响进行溯源,得出指向误差影响姿态处理结果可从两个方面进行分析。同时对模型内交会算法的直接影响和模型外动态基准的间接影响进行推导分析,将仿真计算和实测数据进行结合验证,获取了在典型中长远光学姿态测量中指向误差200″对姿态角误差不超过0.1°的结论,为现有姿态测量可靠性分析以及后续靶场设备能力拓展奠定了理论基础。 相似文献
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Instantaneous frequency measurement using two parallel I/Q modulators based on optical power monitoring
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A scheme for instantaneous frequency measurement(IFM)using two parallel I/Q modulators based on optical power monitoring is proposed.The amplitude comparison function(ACF)can be constructed to establish the relationship between the frequency of radio frequency(RF)signal and the power ratio of two optical signals output by two I/Q modulators.The frequency of RF signal can be derived by measuring the optical power of the optical signals output by two I/Q modulators.The measurement range and measurement error can be adjusted by controlling the delay amount of the electrical delay line.The feasibility of the scheme is verified,and the corresponding measurement range and measurement error of the system under different delay amounts of the electrical delay line are given.Compared with previous IFM schemes,the structure of this scheme is simple.Polarization devices,a photodetector and an electrical power meter are not used,which reduces the impact of the environmental disturbance on the system and the cost of the system.In simulation,the measurement range can reach 0 GHz-24.5 GHz by adjusting the delay amount of the electrical delay lineτ=20 ps.The measurement error of the scheme is better at low frequency,and the measurement error of low frequency 0 GHz-9.6 GHz can reach-0.1 GHz to+0.05 GHz. 相似文献
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为了研究探测光波长的漂移对能见度测量的影响。从Koschmieder经验公式的定义出发,根据实验测得400 nm~1 100 nm波段的气溶胶透过率,分析研究探测光波长漂移对能见度测量结果的影响。结果表明,能见度测量的相对误差与探测光波长和波长的漂移范围以及气溶胶消光特性有关,能见度测量的相对误差随着探测光的波长漂移范围线性增大,随着波长漂移范围的增大,各个波长的能见度测量相对误差线性增大的速率不同,对于相同的波长漂移范围,使用不同的探测光波长产生的能见度测量相对误差不同。对于某一大气环境,使用特定的波长而且中心波长稳定的光作为探测光可以明显减小由于探测光波长漂移引起的能见度测量相对误差。 相似文献
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中国科技大学国家同步辐射实验室"光谱辐射标准与计量实验站"上的反射率计主要用于测量各种光学元器件在X射线、真空紫外波段的反射率.为保证测试结果的精确性和可靠性,在大量实验数据的基础上,结合必要的理论推导,对反射率计测试误差来源及影响程度进行了分析,确定影响反射率计测试精度的主要因素包括光源、探测器、样品安装等.总结了光源波动、探测器损坏的几种典型形式,定性、定量地分析了这些因素和样品安装、光斑尺寸对测试精度的影响,针对性地提出了应对办法,把测试误差控制在2%以内,从而有效地保证了测试精度. 相似文献
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A novel scheme to the area measurement of multiple objects is proposed. This scheme is suitable for the simultaneous and exact measurement of multiple objects’ surface areas with different shapes. A geodesic active contour is applied and this scheme consists of three steps. Firstly, the active contour converges to the object's contour edge from an initial position via the iteration of level set functional ?. Secondly, for the convergent active contour, the sub-pixel area measurement and centroid measurement are applied to compute every object's area and centroid simultaneously. Finally, a centroid-self-calibration technology is applied, which measures the pixel's size equivalence with the computed centroid and a dual-frequency laser to measure every object's true surface area. Experiments indicate that this scheme's measurement repetition error can decrease to ±0.4% and that its single measurement error can decrease to ±0.2%. Compared to conventional area measurement schemes, this scheme is highly efficient (i.e., simultaneous measurement of multiple objects’ areas) and highly accurate. 相似文献
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A novel scheme to measure the true boundary perimeters of multiple planar objects is proposed. This scheme is suitable for the simultaneous and accurate measurement of multiple objects’ boundary perimeters with different shape. A geodesic active contour is applied and this scheme consists of three steps. First, the active contour converges to the object's contour edge from an initial position via the iteration of the level set functional . Second, for the convergent active contour, the sub-pixel edge detection and the centroid measurement are applied to obtain every object's edge and centroid coordinate simultaneously. Finally, a centroid-self-calibration technology is applied, which measures the pixel's size equivalence with the computed centroid and a dual-frequency laser to measure every object's true boundary perimeter. Experiments indicate that this scheme's measurement repetition error decreases to ±0.4% and that its single measurement error decreases to ±0.2%. Compared to conventional perimeter measurement schemes, this scheme is highly efficient (i.e., simultaneous measurement of multiple objects’ boundary perimeters) and highly accurate. 相似文献
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In the field of quantum information,the acquisition of information for unknown quantum states is very important.When we only need to obtain specific elements of a state density matrix,the traditional quantum state tomography will become very complicated,because it requires a global quantum state reconstruction.Direct measurement of the quantum state allows us to obtain arbitrary specific matrix elements of the quantum state without state reconstruction,so direct measurement schemes have obtained... 相似文献
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基于光学测棒的立体视觉坐标测量系统的研究 总被引:7,自引:2,他引:5
提出了一种基丁测量与校准功能合一的光学测棒的立体视觉坐标测最系统.采用光学测棒作为成像目标,通过任意放置的两台摄像机获取测棒上的发光特征点的图像实现被测物体三维坐标的测量,同时利用测量数据定期对两台摄像机外部方位参数进行校准.深入研究了两台摄像机内部参数和外部方位参数校准过程中的校准件和校准算法的设计,以及系统测量建模等关键技术,提出了相应的解决方案,减小了摄像机内外参数校准及测量模型对测量结果的影响,提高系统的测量精度.实验结果表明.该系统的最大测量误差为0.11 mm. 相似文献
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为测量高能激光传输系统中大口径高反射率光学元件的反射率,设计了一种大口径光学元件二维扫描的精密测量系统。介绍了该系统的结构及其工作原理,分析了影响系统测量精度的因素,从理论上分析了扫描系统的系统误差对测量精度的影响,结果表明在垂直于光束传播方向上,水平偏差在0.29 mm时,测量误差在10-6量级;腔长的变化量较小时,可通过对衰荡腔腔镜的调节,实现对旋转轴偏差的补偿及对系统的精细调节。通过拟合处理光强与时间的数据得到对应的一次指数函数拟合曲线,并通过计算得到衰荡时间和反射率,经过对比分析可知,该误差分析方法能比较有效地测量腔镜的反射率,并能减小实验数据本身带来的误差。 相似文献
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斜光轴面内位移测量的数字散斑相关法研究 总被引:2,自引:0,他引:2
以工程环境中远距离位移和位移场的光学测量为研究课题,分析了远距离斜光轴成像时,像模糊和成像位置变化对白光数字散斑相关方法产生的影响,给出了这两种影响的误差理论计算公式。提出使用参考测量技术克服斜光轴成像位置变化带来影响,给出一种新的远距离斜光轴高精度测量面内位移的方法,在2~50m处作静载挠度测量,其最大相对误差小于1%,测量精度在实验室环境和工程测量环境中都得到了验证。该方法无需共轴光路的测量环境要求,特别适用于桥梁、高速公路立交桥的静载挠度测量等工程应用。使用高速图像采集卡,该方法可应用于斜光轴动态位移测量,拓展了数字散斑相关方法的应用范围。 相似文献
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大口径元件反射率的镜面扫描精密测量系统 总被引:4,自引:2,他引:2
为了测量高功率激光传输系统中大口径高反射率元件,研制了一种镜面扫描的精密测量系统。介绍了该系统的结构及其工作原理,分析了影响系统测量精度的因素,理论上估算的测量精度为2×10-5。在直腔下对该系统的性能进行了实验测试,分析表明,系统的测量不确定度优于2.052 28×10-5,最大测量误差为3.554 04×10-5,与理论预计结果吻合较好。对大口径元件进行的多次实验扫描测试,结果显示,镀膜加工误差导致反射率分布是关于镜面中心呈旋转对称。该系统的使用大大简化了元件表面反射率分布的测量。 相似文献
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针对传统基于正弦波磁光调制的方位失调角测量系统存在测量精度不高的问题,提出了一种新的系统方位失调角测量模型以提高系统测量精度。通过分析传统的基于正弦波磁光调制的方位失调角测量原理发现,由于采用省略高阶项的贝塞尔函数展开式表示磁光调制后的信号,引入了信号截断误差和方法误差,影响了系统测量精度。在分析基础上推导建立了一种基于纯三角函数表示的无理论误差的方位失调角测量新模型并进行了仿真。仿真结果表明,利用推导建立的失调角测量新模型,系统测量精度明显高于传统方法,这对重新理解基于正弦波磁光调制的方位失调角测量系统原理、提高系统测量精度具有一定的参考意义。 相似文献