浅谈大尺寸预制棒表面预处理

进入成熟期的光纤光缆行业选择大尺寸预制棒高速拉丝技术是提高生产效率、降低生产成本的主要发展方向之一.大尺寸预制棒表面预处理是大尺寸预制棒高速拉丝技术中的重要环节,其直接影响光纤的质量.本文主要探讨大尺寸预制棒表面预处理的工艺选择与设备控制,及处理效果的分析.     

浅析大尺寸光纤预制棒(OVD法)的制备工艺

光纤预制棒的大型化是降低光纤拉丝成本的必要手段,本文介绍了利用OVD法生产大尺寸光纤预制棒的工艺方法,主要包括大尺寸光纤预制棒在沉积、烧结、保温过程中的设备与工艺介绍.     

拉丝工艺对光纤性能的影响

分析了不同折射率结构预制棒的拉丝结果,探讨了拉丝工艺与光纤折射率的关系。基于扩散原理和玻璃材料光弹效应特性,阐述了折射率对光纤性能的影响以及通过调节预制棒拉丝张力和炉温来调整光纤折射率,进而实现优化光纤模场直径(MFD)、截止波长(λc)、衰减等参数的目标。     

大尺寸光棒高速拉制技术的精细化探索

通过对光纤拉制工艺进行改进,将高温炉、送棒系统、冷却系统、固化系统和收丝系统进行适应性改进,并严格拉丝过程控制,烽火通信在大尺寸光棒高速拉制技术方面进行了精细化改善的有益探索,实现了长达2m,直径达150mm以上的大尺寸光纤预制棒的高质量拉制,可实现一次性稳定拉制光纤长度达到2500km的水平,有力提升了光纤的产出效率,大幅提高了光纤的产品质量。     

半导体锗芯光纤拉丝过程中的芯-包层流速差异研究

半导体芯光纤因其特殊的光电特性而受到广泛关注。由于纤芯和包层材料之间的性质差异,制备高质量的半导体芯光纤比传统掺杂石英玻璃光纤更为困难。以锗芯光纤为研究对象,通过有限元法,模拟仿真了激光拉制锗芯光纤的动态过程,研究了拉制过程中芯层锗和包层石英玻璃材料的流速差异,以及不同拉丝速度对其流速差异的影响。仿真结果表明:在预制棒颈缩区,芯层锗和包层石英玻璃材料的流速差异最大,且不同拉丝速度对预制棒芯层锗和包层石英玻璃材料的流速影响不同。     

高功率光纤激光器用20/400双包层掺镱光纤

采用改进化学气相沉积结合溶液掺杂法制造出了掺镱石英光纤预制棒,预制棒轴向上芯径波动小于5%,折射率差波动小于8%。研磨加工后拉制出20/400双包层掺镱光纤,光纤纤芯不圆度为2%,芯包同心度偏差为0.87 μm。双包层掺镱光纤在1095 nm的包层损耗为2.1 dB/km。采用拉制的掺镱双包层光纤作为直接振荡结构全光纤化激光器的增益光纤实现了1195 W的1080 nm激光输出,斜率效率达82%。     

降低单模光纤损耗的工艺研究

结合光纤散射机理分析,从光纤预制棒折射率分布、掺杂浓度、拉丝张力和拉丝热处理等方面着手研究,通过优化预制棒沉积工艺和改善拉丝条件来制备低损耗单模光纤,并采用光时域反射仪(OTDR)进行检测,结果表明,单模光纤在满足ITU-T G.652标准的同时,在1 550nm波长的衰减可进一步降低。     

单模光纤光缆的性能与检测

介绍了单模光纤的传输性能（衰减、色散）和光学几何特性（截止波长、模场直径、包层直径、模场同心度误差、包层不圆度）及其测试；光缆的机械性能（拉伸、压扁、冲击、反复弯曲、抗弯折）和环境性能（衰减温度特性等）及其检测。     

单模光纤光缆的性能与检测

介绍了单模光纤的传输性能(衰减、色散)和光学几何特性(截止波长、模场直径、包层直径、模场同心度误差、包层不圆度)及其测试；光缆的机械性能(拉伸、压扁、冲击、反复弯曲、抗弯折)和环境性能(衰减温度特性等)及其检测。     

微结构聚合物光纤套管法拉丝工艺

通过对微结构聚合物光纤拉丝工艺的研究,提出微结构聚合物光纤二次预制棒套管拉丝技术.为了降低光纤拉伸过程中微孔坍塌率,从光纤拉伸力和材料表面张力之间平衡的角度考虑,对拉丝炉中热区温度和长度进行控制,得到了预制棒拉丝炉和光纤拉丝炉中热区温度分布曲线.最后,通过对本体聚合法制备的椭圆芯六角对称微结构聚合物光纤预制棒的拉丝实践...     

High-speed high-strength fiber drawing

A review of high-speed drawing and coating of optical waveguide fiber, and related work is given. This paper also includes a discussion on the effects of fiber pulling at a high draw rate on the optical and mechanical properties of the silica fiber. The coating mechanics that describes high-speed coating application in terms of process variables is explained. Finally, recent achievements with fibers coated at high speeds are presented.     

光纤拉丝机一机两炉的设计改造

改造方案是在原进口中频感应加热炉拉丝机上再加装一台石墨加热炉,使之成为一机两炉工作状态,同时在一台电脑控制下,使用同一拉丝控速系统,可在同一主体设备上分别将大,小直径规格的预制棒拉制成光纤.     

Microstructure analysis in the coupling region of fiber coupler with a novel electrical micro-heater

Fused-tapered fiber coupler is widely used in optical-fiber communication, optical-fiber sensor and optical signal processing. Its optical performance is mainly determined by the glass properties in the coupling region. In this study, the effect of fused biconical taper (FBT) process on glass microstructure of fiber coupler was investigated by testing the microstructure of the cross-section of coupling region. The fiber coupler is fabricated with a novel home-designed electrical heater. Our experimental results show that the boundary between fiber core and fiber cladding become vague or indistinct after FBT under transmission electron microscopy (TEM) and Ge²⁺ in fiber core diffuses into fiber cladding. Crystallizations are observed in coupling region under scanning electron microscope (SEM) and microscopic infrared (IR), and the micro crystallizations become smaller with the drawing speed increasing. The wave number of fiberglass increases after FBT and it is in proportion to the drawing speed. The analysis of the microstructure in the coupling region explored the mechanism of the improvement in the performance of fiber couplers which can be used for the guidance of fabrication process.     

大尺寸气孔微结构光纤在光纤光栅中的应用

将微结构光纤分为光子晶体光纤和大尺寸气孔微结构光纤两种。详细介绍了大尺寸气孔微结构光纤。其包层的气孔硅结构（或者聚合物硅结构）影响了包层模式的空间分布以及包层模式的有效折射率，使其表现出与传统光纤不同的光学特性。基于这种微结构光纤的光纤光栅对外部折射率的变化显示了很好的稳定性。偏振特性（对长周期光纤光栅）可以大大加强。基于聚合物硅包层的长周期光纤光栅显示了优良的温度调谐性能。     

折射率引导型微结构光纤的奇异非线性效应和应用

折射率引导型微结构光纤不但有很多新颖的色散特性,而且还有很高的等效非线性系数,这两者相结合赋予RG-MOF很多独特的基于非线性特性的应用。介绍这种光纤中所产生的强非线性效应,如超连续谱生成、三次谐波生成和光学孤子生成等,然后参照最新的研究报道介绍其最新应用,如MOF波长转换器、高速信号分离器、基于SC分离的多信道脉冲源。     

一种耐高温光纤的制备方法

耐高温光纤涂料聚酰亚胺采用电炉加热,固化的时间长,不能满足大预制棒高速拉丝中长距离涂覆和快速固化的要求。本文介绍一种利用MCVD＋VAD工艺制作预制棒,在高速拉丝机上进行聚酰亚胺涂覆、快速固化的长距离耐高温光纤的制备方法。     

Cladding Layer Impedance Reduction to Improve Microwave Propagation Properties in p-i-n Waveguides

The cladding layer effect on microwave propagation properties of semiconductor p-i-n waveguides is investigated in this letter. Through the optical excitation in quantum wells of p-i-n waveguides, high-speed photocurrent is used to examine the microwave propagation. Two devices of p-i-n waveguides with different cladding layers are fabricated and measured, showing that a higher speed is found in the waveguide of wider cladding width. Verified by the microwave propagation properties, the higher speed is mainly attributed to lower microwave propagation loss due to the lower impedance in the wider cladding layer, suggesting this kind of structure can be applied to high-speed waveguide-based devices     

High-birefringence polarizing fiber with flat cladding

This paper presents the theoretical and experimental investigations on polarization characteristics of PANDA fiber with flat cladding. It is theoretically shown that the modal birefringence in the flat-clad fiber is almost the same as that in the circular-clad fiber. The flat-clad PANDA fiber has been fabricated by grinding off the preform cladding on the opposite faces and then drawing with a low furnace temperature. The modal birefringence of the fiber isB = 5.9 times 10^{-4}and the separation of the bending loss edges for the two polarization modes isDeltaupsilon = 0.51in the normalized frequency. The polarizing region can be tuned from 1.3 to 1.56 μm by varying the fiber-bending diameter from 3.5 to 4.5 cm. A 1.5-m length of polarizing fiber exhibits extinction ratios of 44.9 and 44.4 dB with insertion losses for the guided mode of 0.25 and 0.41 dB at 1.3 and 1.56 μm, respectively.