波导阵列与光纤阵列的遗传算法自动对接

设计了一种新的阵列对接方法,即将遗传算法导入光纤、光波导分支耦合器、光纤阵列的自动对接。数值仿真结果表明,常规的八通道波导分支耦合器的对接耦合能实现各通道小于9.1dB的插入损耗,最大值与最小值之差小于0.1dB,即自动对接方案具有良好的性能。     

光波导-光纤自动调芯系统研究

设计了两种适用于光波导高精度自动对接耦合的调芯方案，从原理上克服了常规调芯过程中微变信号精确测试的困难。完成了调芯系统的光机电一体化、控制程序和接口界面。单模光纤作为标准波导的端面耦合自动凋芯试验显示，平均耦合损耗分别为0．075 dB(1310nm波长)和0．062 dB(1550nm波长)，相应的标准误差分别为0．0099 dB和0．0066 dB．调芯过程在2min内完成。单模光纤-单模波导-单模光纤的对接耦合实验结果表明，端面耦合损耗平均值分别为0．140 dB(1310nm波长)和0．109 dB(1550nm波长)，标准误差分别为0．0082dB和0．0107dB，调芯时间累计不超过8min。     

波导阵列与光纤阵列的智能算法自动对接

开发了一种遗传算法和中心寻优算法相结合的阵列自动对接方法,试制了调芯系统,实现了光纤-光波导1×8分支耦合器-光纤阵列系统的自动对接.实验中8个通道的插入损耗平均值为-10.5 dB,均匀性小于0.5 dB,自动调芯时间小于10 min.实验结果表明该方法及其系统具有实现自动高效、低损耗对接的良好性能.     

光波导-光纤耦合对接自动化系统的研究

开发设计了三种适用于光波导自动对接耦合的调芯方案：半值法、质心法、遗传法.完成了自动对接系统样机.通过了两类波导－光纤自动端面对接的实测.结果表明，该自动对接系统具有高效率低损耗对接的良好性能.     

多孔硅通道型光波导的制备及传输损耗的测量

利用多孔硅在阳极腐蚀过程中外加的光照度与孔隙率的对应关系,提出了一种利用光照控制多孔硅折射率的方法制备通道型光波导技术.对制备出的多孔硅波导损耗进行了分析.由于多孔硅波导层中孔状结使得波导端面较为粗糙,耦合损耗大是多孔硅光波导传输损耗测量中遇到的的问题,对此采用了一种非破坏性的简便的优化端面耦合传输损耗测量方法,可以实现入射光束与波导的完全耦合,消除了因光波与波导中导波模式间失配引起的损耗.较精确的测量出实验中制备的通道型多孔硅光波导的传输损耗为16.2dBcm,波导端面的散射损耗为3.6dB.     

基于遗传算法的集成光子器件对准

设计了一种基于遗传算法的集成光子器件自动对准方法.该算法克服了对准搜索中的早熟现象,改善了简单遗传算法搜索后期收敛速度慢的缺陷.仿真实验表明,在平面光波导与单模光纤自动对准过程中,该改进的遗传算法平均检测207个空间点时达到了0.01 dB的对准功率损耗.     

SOI波导光传输损耗和端面耦合损耗的精确测量与理论分析（英文）

采用法布里-珀罗(Fabry-Perot)谐振腔(也称F-P腔)方法测试SOI波导光传输损耗及其与光纤的端面耦合损耗的测量精度,对具有相同尺寸长度为8.37 mm的三条SOI波导通道进行测量,得到SOI波导光传输损耗和端面耦合损耗的平均值与测量精度值,且测量精度偏差值很小。通过温度的自动控制扫描仪对另一条长度为12.5 mm的SOI波导进行三次重复测量,获得的传输损耗值和端面耦合损耗值相同,说明采用F-P腔方法获得的测量精度值很稳定。建立了SOI波导传输损耗测量精度da/a与F-P腔谐振输出功率极限值消光比的相对误差dtM/tM和SOI波导端面菲涅耳反射系数的相对误差d R/R之间关系的理论模型。模拟结果表明:改变SOI波导上、下包层和芯层折射率,对光传输损耗和波导-光纤端面耦合损耗的测试精度无影响。数值模拟结果与实验测试结果相一致。     

面向光印刷电路板的聚合物光波导制备及性能研究

选用紫外固化型环氧树脂,采用光刻技术在FR-4基板上制备了平行排布的多模聚合物光波导。波导具有阶跃折射率分布,相邻波导间隔为250μm,可与并带后的50μm芯径多模光纤实现多通道低损耗耦合。通过搭建测试平台,对波导的插入损耗、串扰及错位容限进行了测量与分析。实验结果表明,所制备光波导的损耗小于0.05dB/cm,串扰小于-60dB。波导在错位容限方面性能良好,当输入端错位±5μm时,系统增加的插入损耗小于0.2dB。同时根据实际波导建立仿真模型,采用光束传播法分析了不同入射条件下的模式能量分布、差分模式延时及耦合效率。计算结果表明,使用与波导具有相近纤芯尺寸的入射光纤不仅可以减小耦合损耗和串扰,还能减少激发起的高阶模式数,提高波导的距离带宽积,优化光波导的综合传输性能。所制备的聚合物光波导作为组成光印刷电路板的核心光器件具有良好的应用前景。     

光纤／波导器件／光纤系统的损耗分析

测试分析光纤／波导器件／光纤系统的损耗，并介绍几种减小端面耦合损耗的对准方法。     

电光聚合物波导中的锥形结构

提出并设计了一种基于电光聚合物的锥形波导,可用于单模光纤与电光聚合物波导器件之间的连接.锥形波导中采用了宽度锥形和折射率锥形结构.宽度锥形采用劈形形状,通过宽度和折射率的缓慢变化实现模场转换.劈形形状的宽度锥形具有较小的损耗且易于制作,折射率锥形可采用灰度掩膜光刻技术制作.研究了锥形波导的传输损耗与锥形波导的长度、波导宽度和厚度、材料吸收损耗等参数的关系及其优化,分析了锥形波导中的功率传输、模场分布与模式转换效率.结果显示锥形波导的传输损耗小于0.37 dB,光纤-波导-光纤的连接损耗优于1.62 dB,对插入损耗的改善达到8.78 dB,模场转换效率达到了83.7%.     

Automatic optic waveguide chip packaging system based on center-integration algorithm

In order to realize efficient automatic packaging of the waveguide chip and reduce its cost, an integrated optic waveguide chip packaging system based on center-integration algorithms is designed and fabricated, which realizes 11-dimension position adjustment and fewer operation times. The integration center position is obtained through the sampling data. The system can avoid local optimum and reduce packaging time as well as packaging loss. The automated alignment of a single-core fiber with channel waveguide and single-core fiber system is completed in less than 2 min. The packaging experiment of a single-core fiber array with 1 × 8 splitter coupler and 8-core fiber array is completed in less than 5 min with an insert-loss of less than 10.5 dB and homogenization of less than 0.4 dB. The system is validated with good efficiency and practicability.     

光通信中的玻璃无源器件的制备与研究

本文报道了以高质量的BK7光学玻璃为衬底,通过稀释Ag+-Na+离子交换技术,制备出低损耗的表面条波导,并用近场法测量出条波导的模场分布曲线。给出光纤与波导耦合的失配损耗为0.54dB,条波导传输损耗为0.21dB/cm.以及在此工作基础上,成功地研制了适用于大容量相于光通信系统的1×2和1×4单模波导分束器。     

一种基于机器视觉的平面光波导器件封装手动耦合系统

 对平面光波导器件封装手动耦合系统进行了改进,增加了3个黑白摄像头,3张AV转USB采集卡,通过采集卡采集对准图像,利用LabVIEW8.2和IMAQ vision软件编程,将图片进行BCG调节、反转、闭合、边缘提取、手动阈值、形态学变化、直线拟合等一系列处理和识别后,实现了对光波导分路器与输入、输出光纤阵列的平行度和像素距离的检测,以一个熟练工封装1×32路平面光波导来说平均节省了对接封装时间10 min,减少了操作者的劳动量,减小了对准损耗,减小了人为误差。     

Design for beam splitting components employing silicon-on-insulator rib waveguide structures

We present a new design for beam splitting components employing a silicon-on-insulator rib waveguide structures. In the new design, a high-index thin-film layer is deposited in the rib section to reduce the wave field dispersive tails in the slab section and accordingly render the mode field a confined spot. This in turn improves the beam splitting performance of some conventional waveguide components such as y branches and multimode interference couplers (MMICs), in terms of the excess loss, fiber coupling loss, and compactness of these components. For a 1 x 2 y-branch beam splitter, the excess loss can be as small as 0.43 dB in the new design, which is much lower than that for a conventional rib waveguide structure (which is 1.28 dB). For a 1 x 2 MMIC in our example, the new rib waveguide structure presents an excess loss of 0.064 dB for the TE mode and 0.046 dB for the TM mode, with negligible nonuniformity in dimensions of 30 microm x 1040 microm, whereas its counterpart (i.e., the one with the same dimensions but without a thin-film layer) presents an excess loss of approximately 0.86 dB for both modes. A conventional MMIC must have dimensions larger than 70 microm x 5650 microm to maintain almost the same low excess loss.     

Hybrid Integration of 1 × 12 Metal-Semiconductor-Metal Photodetector and Polyimide Waveguide Array

We report here a demonstration of hybrid integration of a 1 × 12 metal-semiconductor-metal (MSM) photodetector array and polyimide channel waveguides via 45° total-internal-reflection (TIR) micro-couplers. The two-layer polyimide waveguide array was constructed using Ultradel 9120D for the core and Ultradel 9020 for the lower cladding layer. The coupling loss and propagation loss of the waveguide are 0.2dB and 0.21 dB/cm, respectively. The cross talk of the adjacent channels is -32 dB. The MSM photodetector array was fabricated on a semi-insulated GaAs wafer. The photodetectors are integrated to operate in the conventional vertical illumination mode. We measured the external quantum-efficiency and 3 dB bandwidth of the integrated MSM photodetectors at 0.4 A/W and 2.648 GHz, respectively. The aggregate 3 dB bandwidth of the 12-channel integrated system is 32 GHz.     

Design and fabrication of a three-dimensional polymer optical waveguide polarization splitter

We present a design and fabrication of a three-dimensional polymer optical waveguide polarization splitter by taking into consideration of the induced birefringence effect of the polymer. We show that it is not possible to couple TM light from one waveguide to the other but evanescent coupling for TE light is possible. Hence the polarization splitter can be designed by considering TE mode coupling alone. This has an advantage of short interaction length of the device. Based on this consideration, we fabricated a polarization splitter with a TE extinction ratio of 15 dB and TM extinction ratio of 21 dB.     

基于达曼光栅的动态光耦合器

提出了一种基于达曼光栅的动态光耦合器,通过控制装置中达曼光栅位移参量,可实现入射光束的分束或合束以及两者之间的动态转换。适当选择达曼光栅类型可实现任意N×M的动态光耦合。实验中以1550 nm光波长为例,对1×8达曼动态光耦合器进行测量,测得其实现光开关功能时插入损耗为0.43 dB,实现光分束功能时均匀性达到0.03,单路插入损耗均值为10.5 dB。该实验装置易于调节、体积小、能耗低,且关键元件达曼光栅制作工艺成熟,易于批量化生产。特别是在实现中大规模光交换阵列时,该方案就具有更明显的优越性,有实用意义。