共查询到19条相似文献,搜索用时 345 毫秒
1.
2.
3.
介绍了光纤Mach-Zehnder(MZ)干涉仪系统的结构.给出了光纤Mach-Zehnder干涉仪系统中信号光与参考光的干涉原理以及影响干涉光强的因素.同时也分析了光纤耦合器的交叉耦合,另外也给出了PZT的作用.阐述了光纤偏振控制器结构、工作原理以及其对光纤Mach-Zehnder干涉仪系统传感臂偏振态的控制,最后给出了光纤Mach-Zehnder干涉仪系统的应用. 相似文献
4.
光纤干涉仪中的偏振态保持或控制技术是干涉型光纤传感器研究中极为重要的一个问题.特别当干涉光的两臂中的偏振态正交时,干涉仪输出的干涉信号为零,这时传感信号将完全消失.这原则上可以采用保偏光纤技术解决,但目前保偏光纤和保偏光纤耦合器成本高、技术不完善,人们对光纤水声传感器等干涉型光纤传感器中的偏振衰落问题的解决一般采用低双折射率光纤加消偏振态衰落或偏振控制的方式.经过研究分析,可以认为光纤干涉仪中的两臂偏振态的变化总体效果等同于从第一只耦合器输入光波的偏振态变化,当该输入偏振态的变化等于光纤干涉仪中两臂偏振态的反变化时,输入偏振态补偿了干涉仪中的偏振变化,因此有可能通过控制输入端光纤的偏振态达到对光纤偏振控制的目的.
对光纤干涉仪输入偏振态的反馈控制机理做了较深入的理论分析,推导出反馈系统的反馈信号与输入偏振态的关系式,建立并根据系统闭环控制物理模型,分析了光纤偏振控制器电压初始值要求及该反馈系统可能存在的稳定点,对消偏振衰落系统的设计和制作有较大的指导意义.(PD12) 相似文献
5.
介绍了光纤Mach-Zehnder(MZ)干涉仪系统的结构,阐述了该系统中信号光与参考光的干涉原理以及影响干涉光强的因素,分析了光纤耦合器的交叉耦合和PZT的作用,描述了光纤偏振控制器的结构、工作原理及其对光纤Mach-Zehnder干涉仪系统传感臂偏振态的控制,最后介绍了光纤Mach-Zehnder干涉仪系统的应用。 相似文献
6.
光纤干涉仪消光比调谐方法 总被引:1,自引:0,他引:1
简要介绍了目前超长距离光纤干涉传感系统的发展现状,并在理论上分析了光纤传感系统中的偏振态对消光比的影响以及能够影响光波偏振态的各种因素.将基于光弹效应的挤压型偏振控制器应用于该系统的消光比调谐,给予光纤干涉臂径向应力,动态调谐系统光波偏振态,实现了长距离光纤传感系统的消光比在一点上的调谐.提出了长距离光纤传感系统灵敏度... 相似文献
7.
针对低双折射光纤双光束干涉型传感器两臂偏振态随机变化引起的信号衰落,提出了一种新型消偏振方式,它可以在可见度略有下降的情况下,较好地消除偏振态变化引起的信号可见度的随机变化。该方案是通过相互正交的两个偏振态来补偿由于其中一个偏振态变化导致的干涉信号衰落。通过自动增益控制电路可以使传感信号稳定,能够在信噪比有所下降的情况下消除偏振衰落的影响,实现了干涉型光纤传感器的消偏振衰落。 相似文献
8.
9.
双光束干涉型光纤传感器抗偏振消衰落技术 总被引:4,自引:0,他引:4
对干涉型光纤传感器中光波偏振态的随机变化导致待检测信号衰落的原理进行了理论分析,系统地总结了目前国内外关于双光束干涉型光纤传感器抗偏振消衰落措施的最新研究成果。 相似文献
10.
干涉式光纤陀螺(IFOG)中光波偏振态的变化对输出信号的质量会产生很大的影响,本文从原理上分析了保偏和消偏这两种消除偏振误差的方法,其中基于光纤环的消偏器具有很高的性能和实用价值. 相似文献
11.
Experimental demonstration of an all-fiber endless polarization controller based on Faraday rotation
J. Prat J. Comellas G. Junyent 《Photonics Technology Letters, IEEE》1995,7(12):1430-1432
An all-fiber device for the control of the state of polarization (SOP) is presented. The controller is high speed (its time response is less than 50 ms in the worst case), low loss (insertion losses are 2.5 dB independently of the input SOP), and low cost (is constructed with standard single-mode fiber). The polarization controller has been implemented using two Faraday rotators and works at 1550 nm. We have also designed an algorithm that confers an endless performance to the device. The controller has been included in a 2.5 Gb/s CPFSK optical coherent system and results are presented here. 相似文献
12.
《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》1987,75(11):1498-1511
A variety of optical components have been made directly from single-mode fibers. These components can be combined to construct in-line all-fiber systems such as fiber gyroscopes, fiber Raman lasers, local area networks, or coherent lightwave systems. This paper reviews the present state of passive and active single-mode fiber components. Passive components are polarizers, directional couplers, filters, and Faraday rotators. Active components require external control or optical power and include modulators, polarization controllers, frequency shifters, and amplifiers. Polarization is usually important in fiber components and discussions of polarization-maintaining and ordinary single-mode fibers are included. 相似文献
13.
We describe an all-fiber Fourier transform spectrometer for decoding the wavelength shifts from a series of Bragg grating sensors. The system described uses an optical fiber Michelson interferometer with one arm wrapped on a piezoelectric driven stretcher capable of inducing a ~10 cm fiber length change. Passive polarization compensation is utilized which eliminates the possibility of random polarization fading in the interferometer causing apodization of the interferogram. This permits an all-fiber design without the need for speciality optical fiber or external polarization adjustments. A reference Nd:YAG laser is used to stabilize the interferometric scan in a phase-locked loop configuration by way of slow and fast feedback correction elements. A spectral resolution of <0.07 cm-1 was obtained, which corresponds to a Bragg wavelength shift of ~0.015 nm in the 1.55 μm region. The simultaneous wavelength determination capacity of the device also permits it to be used in a variety of other applications for analysis of optical spectra 相似文献
14.
We present a detailed study of the polarization properties of a reflective fiber amplifier composed of a circulator, a normal single-mode Er-doped fiber and a Faraday rotator mirror. The amplifier can preserve an arbitrary input state of polarization regardless of any external perturbations, and is completely free from polarization effects. The effect of imperfections of the Faraday rotator mirror is also discussed. Finally, we demonstrate experimentally the polarization-stability of the amplifier and its ability to compensate polarization mode dispersion both in the circulator and in the single-mode Er-doped fiber 相似文献
15.
An all-fiber polarization state controller, which overcomes the problems associated with the temperature dependence of the stress-optic coefficient in previously reported fiber devices is described. The controller consists of two short sections of linearly birefringent monomode fiber oriented with their eigenaxes at 45° with respect to each other. Polarization control is achieved by applying axial strain to each fiber element using piezoelectric transducers. The system is demonstrated by generating polarization states which are made to evolve along trajectories on the surface of the Poincaré sphere. 相似文献
16.
讨论了利用法拉第镜补偿光在光纤中传输的偏振波动,介绍了量子密码术中基于法拉第镜的即插即用系统,并对即插即用系统进行简单相位编码分析。在系统中干涉脉冲遵循确切相同的路径,确保非常高的稳定性和自我补偿,使用法拉第镜自动补偿光纤中的任何双折射效应和偏振相关损耗。 相似文献
17.
Herda R. Kivist S. Okhotnikov O.G. Kosolapov A.F. Levchenko A.E. Semjonov S.L. Dianov E.M. 《Photonics Technology Letters, IEEE》2008,20(3):217-219
We exploit the anomalous dispersion generated by an index-guided photonic crystal fiber (PCF) for dispersion compensation in an ytterbium fiber laser passively mode-locked with a semiconductor saturable absorber. A PCF, reasonably compatible with standard fiber, and a Faraday rotator in the cavity allow for robust all-fiber subpicosecond operation at 1 m, insensitive to environmental disturbance. 相似文献
18.
双光路全光纤电流互感器的研究 总被引:1,自引:0,他引:1
为了使光纤电流互感器具有快速、准确地测量出电流值的能力,本文在分析法拉第电磁感应效应的偏振调制型全光纤电流互感器的基础上引入双光路检测法,将光纤中输出的线偏振光分成振动方向相互垂直、传播方向成一定夹角的两束光。经光信号转换器转换成电信号后系统对其进行放大、滤波处理后得到无噪正弦波信号,结合TMS320F28335测试平台对输出的两路信号进行同步采集、解调,通过运算求出法拉第旋转角,并拟合法拉第旋角与参考电流值得出两者关系式,最终使测量系统能够在高压环境下快速、准确地测量电流值。由此可见,本系统适用于高压环境下对大电流进行检测。 相似文献