置入级联拉锥结构的新型光纤器件研究

发布时间：2018-02-10 05:56

本文关键词： 级联锥形光纤滤波器传感器光纤环镜滤波器　出处：《苏州科技大学》2017年硕士论文　论文类型：学位论文

【摘要】：随着对光通信容量、通信距离及传输速率等要求越来越高,光纤后处理工艺及光电子器件得到了发展。光纤滤波器作为关键器件之一,在现代光纤系统中起到重要作用,其中光纤环镜滤波器是目前最为实用的。其主要滤波原理是一束光信号通过3dB耦合器后被分成两束光并沿着相反方向在光纤环镜腔中传播,最后又会在耦合器处相遇并发生干涉。在环镜腔内置入高双折射光纤、不同突变锥结构光纤及级联锥结构马赫-曾德尔(M-Z)干涉仪等,可以改善滤波器的输出特性。常规光纤中的锥形区,改变了光纤本身物理参数,使得光功率重新分配,纤芯中的部分光能量以倏逝场的形式激发到包层中以高阶模形式传播,这是其调制光场的基础。本文在分析锥区模场特性基础上利用光纤拉锥机和光纤熔接机研制了两类不同突变锥结构的锥形光纤,得到了基于细锥和粗锥的马赫-曾德尔(M-Z)干涉仪,提高了其性能可控性。将其作为传感器实现折射率和温度的测量,将其置入光纤环镜滤波器中,实现输出谱的稳定可调,也可作为波长选择器用于调谐激光器的输出。论文主要工作如下:1.分析了单模锥形光纤基本结构与传输特性,理论分析了锥结构的模式激发耦合原理得到模场半径和纤芯半径的关系。着重介绍了基于拉锥机和熔接机的突变锥耦合点的制作以及制作过程中的注意事项和关键技术。2.基于细锥和粗锥制作了两种不同锥结构的级联对称型光纤。通过比较单锥与级联锥透射谱性能,研究了不同锥间隔下的透射谱效果,并得到最佳效果的级联锥结构参数:细锥型光纤锥腰直径50um,过渡区约为5mm,锥间隔L=13.1cm,粗锥型光纤锥腰直径165um,锥长为450um,锥间隔L=10cm。锥间隔与透射谱波峰间隔呈反比,包层模有效折射率变化会导致干涉谱波长偏移,基于此原理可用于外界折射率和温度的测量。3.将研制的M-Z干涉仪分别用于折射率和温度传感,酒精溶液折射率测量中,对实验数据的拟合分析得到基于细锥和粗锥的光纤M-Z传感器的灵敏度分别为-120nm/RIU和-152nm/RIU。将M-Z干涉仪的传感臂作腐蚀或熔接处理后进行温度传感,调节环境温度并跟踪透射谱的两个峰值点1、2。当传感器环境温度在25~40℃之间变化时,实验得到细锥型光纤M-Z峰1、2处对应的温度响应灵敏度分别为0.04nm/℃和0.023nm/℃;当环境温度在40~55℃之间变化时,峰1、2处对应温度响应灵敏度分别为0.247nm/℃和0.117nm/℃。粗锥的光纤M-Z传感器峰值1、2对应温度响应灵敏分别为0.096nm/℃和0.070nm/℃。4.将高双折射率光纤、单锥型光纤以及级联锥形光纤分别置入光纤环镜的滤波器,理论和实验研究了其输出谱特性变化。研究发现将光纤单锥置入光纤环镜滤波器后品质因数提高约2倍,调节偏振控制器实现调制深度范围11dB~37dB。将级联锥形光纤M-Z的干涉仪置入光纤环镜滤波器后,得到的输出谱为两种滤波器干涉谱的非相干叠加,在自由谱范围1425~1550nm内,置入级联细锥和级联粗锥后的新型滤波器的调制深度分别为5dB和10dB。透射谱包络形状随着偏振控制器旋转角的调整而改变,在一定波长范围内实现可调谐滤波,调谐范围超过60nm。
[Abstract]:With the optical communication capacity, communication distance and transmission rate requirements more and more high, fiber postprocessing technology and optoelectronic devices has been developed. As one of the key components of optical fiber filters, which plays an important role in the modern optical system, the fiber loop mirror filter is the most practical. Its main principle is a filter light signal through the 3dB coupler is divided into two beams along the opposite direction of the optical fiber ring mirror transmission cavity, and finally will meet and interference in the coupler. In the built-in loop mirror in high birefringence fiber, different mutation cone structure fiber and cone structure of Maher - Del had a cascade (M-Z) interferometer the output characteristics, can improve the filter. The tapered region in normal fiber, change the fiber physical parameters, the optical power redistribution, part of the light energy in the core to form the evanescent field excitation to cladding In the high order form of communication, which is based on the modulation of light field. Based on the analysis of cone mode field characteristics based on the fiber pulling machine and optical fiber splicer developed two different types of mutations of the tapered fiber cone structure, the fine and coarse cone cone - Maher (M-Z) was based on Del interferometer instrument, improve the performance of controllability. As the sensor to realize the measurement of refractive index and temperature, into the fiber loop mirror filter, to achieve the output spectrum is stable and adjustable, can also be used as wavelength selector for tunable laser output. The main work is as follows: 1. analysis of the basic structure of optical fiber and tapered single-mode transmission the characteristics, theoretical analysis of cone structure mode excitation principle of coupling relationship between mode field radius and the radius of the core. This article discusses the matters needing attention in pulling machine and welding machine making and cone coupling point mutation in the manufacturing process based on And the key technology of.2. fine and coarse cone cone made two cascaded symmetrical optical fiber with different cone structure based on spectrum. Through the performance comparison of single cone and cone cascade transmission, transmission spectrum under different cone spacing effect on cascade cone structure parameters and get the best results: fine tapered fiber cone waist diameter 50um. The transition zone is about 5mm, the cone interval L=13.1cm, coarse tapered fiber cone waist diameter 165um, length 450um cone, cone cone interval L=10cm. interval and transmission spectrum peak interval is inversely proportional to the change of effective refractive index of cladding mode will cause the interference spectrum wavelength shift, this principle can be used to measure the.3. temperature and refractive index of the the development of M-Z interferometer used for refractive index and temperature sensing based on alcohol solution refractive index measurement, fitting analysis of experimental data obtained based on the sensitivity of optical fiber M-Z sensor and coarse fine cone cone were -120nm/RIU and -152nm/RIU. M- The sensing arm of Z interferometer for corrosion or welding processing after temperature sensing, regulating temperature and track the transmission spectrum of two 1,2. peak when the change of environmental temperature sensor at 25~40 DEG C, the fine taper fiber M-Z 1,2 peak corresponding to the temperature sensitivity of respectively 0.04nm/ and 0.023nm/ DEG C when the ambient temperature changes; at 40~55 DEG C, 1,2 peak corresponding to the temperature response sensitivity were 0.247nm/ and 0.117nm/. C C fiber M-Z sensor peak coarse cone 1,2 corresponding to the temperature sensitive response were 0.096nm/ and 0.070nm/ C.4. C Gao Shuang index fiber, single taper fiber and tapered fiber are respectively arranged in the optical fiber filter cascade loop mirror, theoretical and experimental studies on the output spectral characteristics change. The study discovered that the single cone fiber placement of fiber loop mirror filter quality factor increased by about 2 times, adjusting the polarization controller. The modulation depth of 11dB~37dB. cascade tapered fiber M-Z interferometer in fiber loop filter, the output spectrum of coherent superposition of two kinds of filter interference spectrum, the free spectral range of 1425~1550nm modulation depth filter placement cascade and cascade coarse fine cone cone after respectively 5dB and 10dB. transmission spectrum the envelope shape change with the rotation angle of the polarization controller, realize tunable filter in a certain wavelength range, the tuning range of more than 60nm.

【学位授予单位】：苏州科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN253;TN713

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