共查询到20条相似文献,搜索用时 15 毫秒
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本文提出并分析了一种新型的光纤干涉仪,该仪器对Mach-Zehnder干涉仪作了适当的改进,使灵敏度提高近6倍.通过对干涉仪臂长的适当调节,还可以实现对“共模”噪声的抑制,减小光源波长波动及环境干扰对系统的影响. 相似文献
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采用有限元法对实验室自制的非线性微结构光纤进行理论分析, 表明该光纤具有良好的非线性和色散波产生的相位匹配特性. 为实现微结构光纤非线性的全光纤化, 本实验采用中心波长为1032 nm的光纤飞秒激光器作为抽运源, 获得了753–789 nm 的近红外色散波. 实验中发现色散波中心波长和带宽随着抽运功率的改变会产生明显变化, 并且在不同光纤长度时, 色散波的频移量不同, 脉冲展宽及频谱也会有明显的变化. 实验结果与理论分析一致. 这些结果对实现微结构光纤非线性的全光纤化具有良好的借鉴作用, 为生物医疗应用特别是非线性光学显微成像术的近红外光源研究打下基础. 相似文献
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We present an overview of our investigation of the spectral properties and photostabilities of squaraine derivatives. The objective was to identify long-wavelength probes with reasonable quantum yields, reasonably long lifetimes, and good photostabilities for use in fluorescence-based assays and/or imaging. Both symmetrical and unsymmetrical squaraines were studied. Based on this investigation the most suitable probes for use in a biological application were found to be the symmetrical indolenine derivatives of the squaraines, which display the highest photostability. Importantly, their quantum yields and lifetimes increase significantly upon covalent and noncovalent binding to proteins (bovine serum albumin, antibodies), demonstrating the usefulness of the squaraines as long wavelength probes. The squaraine absorbance maxima between 630 and 650 nm allows the use of the new commercially available 635- and 650-nm diode lasers. 相似文献
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利用温度对相位调制的全光纤Mach-Zehnder结构型温度传感器,采用CCD摄像头与小型电视连接的办法来观察干涉条纹的移动,并给出温度变化与干涉条纹移动数的关系,以及敏感长度与灵敏度的关系,进一步了解干涉仪作为温度传感器的参数特性及其作为一台测量仪器的定标。 相似文献
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通过温度梯度法制备了Bi2O3:BaF2以及BiF3:BaF2晶体.在Bi2O3:BaF2晶体中观察到了发光峰位于961 nm,半高宽202 nm的超宽带红外发光.在BiF3:BaF2晶体中检测到Bi2+和Bi3+可见区的发光,但是没有观察到红外发光.通过γ射线辐照实现了BiF3:BaF2晶体的近红外发光, 发光峰位于1135 nm,半高宽192 nm.讨论了Bi2O3和BiF3掺杂BaF2晶体的红外发光的机理.
关键词:
近红外发光
铋
氟化钡晶体
γ辐照 相似文献
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为使测量加速度计的传感器小型化、不受电磁干扰 ,根据GRIN透镜在 1 / 4波节处具有入射光线与出射光线成中心对称的特性[1 ] ,首次提出并研制了采用GRIN透镜的微型光纤加速度计。闭环负反馈电路设计技术被应用于该加速度计中 ,使之成为一个具有调宽脉冲再平衡性能的新颖加速度测量系统。通过对该系统进行数字仿真和精度定量分析 ,结果表明 ,该光纤加速度计具有测量线性范围宽、精度高的特点 ,可广泛应用于惯性测控系统中 相似文献
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陀螺是光电系统瞄准线稳定的重要元器件,介绍了一种基于光电系统的光纤陀螺冗余安装方法。在冗余安装陀螺数量确定的前提下,考虑到工程实际应用的安装空间、体积、重量和成本等因素,设计了4个陀螺的八边形金字塔冗余安装方式,对此冗余安装方式的精度和可靠性进行了分析和仿真,并与无冗余安装进行了对比。同时,该安装方式可用于陀螺与磁流体动力学角速率传感器的冗余安装。结果表明,该方法使角速度测量的噪声标准差下降约25.3%,可靠性提升约1.75倍。该方法能有效解决某光电系统受安装空间限制而陀螺精度不够的问题,提升了光电系统可靠性;同时也可应用于三轴陀螺稳定光电系统中,对工程应用有一定的指导作用。 相似文献
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The near-infrared spectra and distribution of excited states of electrodeless discharge rubidium vapour lamps 下载免费PDF全文
The population ratio between the excited states of rubidium in the electrodeless discharge rubidium vapour lamp is calculated according to the near-infrared spectra in the region of 780-1550 nm. By using a 1529 nm laser, we measure the density of natural rubidium atoms at the 5P3/2 level. The populations of different excited states are then clarified. 相似文献
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《光谱学快报》2012,45(10):671-676
AbstractThis article proposes a method for quickly detecting the total aromatics content of diesel fuels based on a deep learning algorithm and near-infrared spectroscopy. First, extract the features of the diesel fuel spectral data and eliminate redundant information through the deep belief nets. Second, use a new extreme learning machine to build a prediction model. The experimental results show that the root-mean-square error of prediction value is 0.715 and the coefficient of determination value is 0.988, which proves that the method has good performance. Compared with other typical prediction methods, this method has better predictive ability. 相似文献
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The near-infrared spectra and distribution of excited states of electrodeless discharge rubidium vapour lamps 下载免费PDF全文
The population ratio between the excited states of rubidium in the electrodeless discharge rubidium vapour lamp is calculated according to the near-infrared spectra in the region of 780-1550 nm.By using a 1529 nm laser,we measure the density of natural rubidium atoms at the 5P 3/2 level.The populations of different excited states are then clarified. 相似文献
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描述了一种车辆寻北车长镜的设计,采用2个光纤陀螺和2个加速度计,解决了惯性测量组件力学编排结构设计与寻北、瞄准线稳定共享陀螺信息的问题,设计系统控制流程和组合算法,在保障车长镜瞄准线稳定精度的同时,增加了车体方位平台非调平状态下任意位置的寻北功能,寻北方法是:车长镜方位固定四位置转动,每个位置点停止、延迟、数据采样、存储,四位置转动完毕后,对存储数据组合、滤波、解算,输出寻北结果。对方案设计、实现途径和解算推导方法作了详细论述,性能测试验证设计实现达到预期效果。 相似文献
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Effect of initial chirp on near-infrared supercontinuum generation by a nanosecond pulse in a nonlinear fiber amplifier 下载免费PDF全文
Theoretical and experimental research on the effect of initial chirp on near-infrared supercontinuum generation by a nanosecond pulse in a nonlinear fiber amplifier is carded out. The complex Ginzburg-Landau equation is used to simulate the propagation of the pulse in the fiber amplifier and the results show that pulses with negative initial chirp produce the widest supercontinuum and pulses with positive initial chirp produce the narrowest supercontinuum when the central wavelength of the pump lies in the normal dispersion region of the gain fiber. A self-made line width narrowing system is utilized to control the initial chirp of the nanosecond pump pulse and a four-stage master oscillator power amplifier configuration is adopted to produce a high power near-infrared suppercontinuum. The experimental results are in good agreement with simulations which can provide some guidance on further optimization of the system in future work. 相似文献
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介绍了一种利用钽酸锂热释电探测器实现的实用化双波长光纤测温仪。测温仪由光学接收系统、信号放大与处理系统及显示系统三部分组成。依照探测器系统的温度分辨率、R(T)~T曲线的线性度及温度灵敏度与各主要技术参数之间的关系,在考虑光路中的选择性吸收气体的影响及探测器的最小可探测功率的基础上,对其工作波长及波长带宽进行了优化设计。分析了仪器的工作波长及波长带宽对温度分辨率及测温灵敏度的影响。结果表明,在测温范围400~1300℃内,当λ1=2 1μm、λ2=2 3μm、Δλ3=20nm时,其测温精度高于0 20%。 相似文献
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According to the phase shift response of a ring resonator, the role of a fiber-optic ring resonator as a multi-path light-wave circuit in white-light fiber-optic interferometric sensors is analyzed. Formulas related to the maximum intensity of the interference fringes and the system parameters are derived by exact mathematic deduction. The main factors affecting the multiplexing capability of the sensor array are discussed. The analysis method not only gives an explicit explanation for the enhancement of multiplexing capability but also can be applied to other structural white-light sensor systems, in which the ring resonator is used as a multi-path light-wave circuit. 相似文献