A Multiexposure Technology for Sampled Bragg Gratings and its Applications in Dual-Wavelength Lasing Generation and OCDMA En/Decoding

In this letter, a multiexposure technology for sampled Bragg gratings is proposed and investigated for the first time. Combined with reconstruction-equivalent-chirp technology, the useless zeroth-order channel can be eliminated and the $pm$1st-order channels can be enhanced significantly. The proposed method is applied experimentally to achieve a dual-wavelength fiber laser and is studied both numerically and experimentally in two ways for the optical code-division multiple access en/decoding system. Its properties may lead to more efficient design and fabrication of grating-based optical devices.      

取样啁啾光纤光栅的时延抖动抑制

研究了用于多通道色散补偿器的取样啁啾光纤光栅时延抖动问题,分析了产生时延抖动的腔效应及抑制时延抖动的切趾技术,分析、比较了切趾前后取样啁啾光纤光栅的时延抖动情况,研究结果表明:取样啁啾光纤光栅的时延抖动与其折射率包络调制形成的外腔效应有关,与取样调制形成的多腔效应无关,对取样啁啾光纤光栅进行包络切趾能够有效地抑制时延抖动.     

弱非周期性相位取样啁啾光栅的优化方法

取样光栅可以同时对多个信道进行滤波或色散补偿，所以在波分复用(WDM)系统中有广泛的应用，其中周期相位取样光栅是一种很有前途的设计方法，但周期取样的方法会使取样光栅的所有信道具有相同的色散补偿能力。提出设计弱非周期性相位取样啁啾光栅的优化方法，通过引入一组与信道色散补偿量有关的啁啾控制参数，可使不同信道的色散补偿量存在差异。运用该方法设计出弱非周期的取样光栅后，可用传输矩阵法来模拟该光栅的复反射谱，结果显示通过调整啁啾控制参数，可方便地控制不同信道的色散补偿能力，从而能实现对光纤链路色散与色散斜率的同时补偿，而且取样函数的幅度值的起伏则被完全消除。     

基于马赫-曾德尔干涉仪和取样光纤光栅的全光纤梳状滤波器

提出了一种基于光纤马赫 曾德尔干涉仪和取样光纤光栅的新型全光纤梳状滤波器。通过对器件的工作原理的理论分析 ,发现耦合器的分束比、取样光纤光栅的光谱特性和干涉臂长差是决定这种全光纤梳状滤波器性能的三个主要因素。并对器件性能进行了模拟计算。实验上获得了信道间隔为 1 0 0GHz的初步实验结果。     

Optical Arbitrary Waveform Generation Based on Sampled Fiber Bragg Gratings

Two approaches are proposed for generating optical arbitrary waveforms using sampled fiber Bragg gratings (FBGs). The manipulation of the optical spectrum of an input pulse is achieved by a sampled FBG which is fabricated using a novel technique based on the reconstruction-equivalent-chirp (REC) method. The key advantage of the REC technique is that it can produce FBGs with various phase profiles using a fabrication system having only micrometer precision. Two examples for the generation of Gaussian doublet pulses are demonstrated, which would find applications in ultra-wideband over fiber systems.     

Dynamic OADM Using Tunable Sampled Bragg Gratings Based on Vernier Effect

A novel dynamic optical add-drop multiplexer（OADM） scheme using tunable sampled fiber Bragg gratings（SFBG） by Vernier effect is firstly proposed. In this scheme, broad wavelength tuning range is achieved by only slightly adjusting the SFBG, the wavelength tuning of OADM will be faster than traditional dynamic OADM.     

取样光栅的特性仿真及其在光纤系统中的应用

基于耦合模理论,运用传输矩阵法对取样光栅的反射谱进行了数值计算,着重分析了光栅长度、占空比及光栅取样周期对取样光栅反射谱的影响规律,基于特性分析讨论了取样光栅在光纤系统中的应用,为以后具体应用提供了理论指导和参考.     

Study of Multichannel Parallel Anti-Symmetric Waveguide Bragg Gratings for Telecom Applications

We theoretically demonstrate the viability of parallel anti-symmetric waveguide Bragg gratings within a two-mode waveguide. These gratings produce reflections with mode conversions. This is the functional equivalent of superimposed Bragg gratings in silica-on-silicon without requiring multilevel etches. Also, due to their weaker coupling constant, these gratings allow for devices with narrow spectral full-width at half-maximum that can process multiple wavelength channels for applications such as optical add-drop multiplexers and optical encoders in optical communication systems     

Multiwavelength Actively Mode-locked Fiber Laser with a Double-ring Configuration and Integrated Cascaded Sampled Fiber Bragg Gratings

A modified multiwavelength actively mode-locked fiber ring laser is proposed and experimentally demonstrated. In this kind of laser, stable multiwavelengths lasing is achieved by integrating cascaded sampled fiber Bragg gratings（SFBGs） into the laser cavity. To implement actively mode-locking technique, a doublering cavity configuration is used to assure that the cavity lengths for all wavelengths lasing are identical. Thus, simultaneous mode locking of all wavelengths has been successfully achieved by using the same mode-locking signal.     

A Note Concerning Modes in Dielectric Waveguide Gratings for Filter Applications

Peng and Oliner, and others have shown that TM-to-TE or TE-to-TM mode conversions occur when a single, lowest order surface wave is incident obliquely onto a wide dielectric grating and that the lowest order converted modes of this sort can cause spurious stopbands which are especially troublesome because they are so close to the desired stopband, In this note it is observed that the spurious response situation is not as bad in the case of a grating cut into a dielectric waveguide (which can be thought of as having two, obliquely incident waves present). In this latter case, the fields have even or odd symmetry which eliminates part of the mode couplings includhrg the lowest order TM-to-TE or TE-to-TM couplings. Experimental and theoretical results indicate that gratings can be made to be free from spurious responses or appreciable radiation over sizeable bands so that they can be useful in at least some kinds of dielectric waveguide filter structures.     

长周期光纤光栅的研究进展及在现代通信中的应用

利用光纤可以制作成光纤布拉格光（FBG）及长周期光纤光栅（LPFG）。FBG和LPFG在现代光纤通信和传感器技术中有着极其重要的应用。文中介绍了LPFG的研究方法和最新研究进展,分析了LPFG的特性并运用其特征给出了LPFG在通信中的应用模式及需克服的问题。展示了LPFG对现代光纤通信的深远影响。     

切趾光纤光栅的切趾深度分析

主要从平均色散、插入损耗、群时延波动(group delay ripple)的幅度和周期随切趾深度的变化等方面,分析了切趾线性啁啾光纤光栅的切趾深度对其特性的影响。并以补偿100km、光纤色散系数Df为17ps/nm·km(1550nm处)的标准单模光纤的色散为例,定量地分析了切趾深度对光纤光栅特性的影响,获得了切趾深度的最优化值。     

切趾光纤光栅的切趾深度分析

主要从平均色散、插入损耗、群时延波动（group delay ripple）的幅度和周期随切趾深度的变化等方面，分析了切趾线性啁啾光纤光栅的切趾深度对其特性的影响。并以补偿100km、光纤色散系数Df为17ps／nm-km（1550nm处）的标准单模光纤的色散为例，定量地分析了切趾深度对光纤光栅特性的影响，获得了切趾深度的最优化值。     

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。     

聚合物光纤光栅的研究进展及应用前景

阐述了聚合物光纤光栅的研究进展，介绍了它的主要特性、制作方法及可能应用。     

聚合物光纤光栅的研究进展及应用前景

阐述了聚合物光纤光栅的研究进展,介绍了它的主要特性、制作方法及可能应用。     

长周期莫尔光栅的理论研究

长周期光纤光栅作为一种损耗型的带阻滤波器，在光纤通信和光纤传感器领域有着广泛的应用。结合长周期光纤光栅的传输特性，利用传输矩阵法对多种长周期莫尔光栅的透射谱进行了理论模拟。分析结果表明，莫尔光栅技术在制作高性能的相移长周期光栅和变迹长周期光栅上有着很好的应用前景。     

相移光纤光栅的反射谱特性分析

应用传输矩阵法对相移光纤光栅(FBG)的反射光谱特性作了详细的理论分析,给出了相应的数学模型,并进行了验证.结果表明,相移的引入导致光纤光栅反射谱产生分裂,分裂点波长与相移大小呈线性正比关系并具有用期性;分裂点反射率与相移位置、光栅中心波长之间具有一定的对称性,且符合双曲正切关系.     

金属化光纤光栅内应力的分析和实验研究

通过化学镀的方法,在光纤光栅表面得到了不同厚度的均匀金属镍镀层。由于材料热膨胀系数的差异,金属镍镀层将会在光栅内部形成内应力,这种内应力将随着镀层厚度的改变而改变。理论上分析了金属镀层的厚度对光栅中心波长漂移的影响,获得相关的理论曲线;实验上通过对化学镀镍全过程光纤光栅反射光谱的在线监测,获得了不同镀镍层厚度的光纤光栅中心波长的改变量,实验数据与理论分析结果吻合较好。