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1.
采用稀释硬脂酸和高温质子交换技术,研究了单偏振α相铌酸锂光波导的制备工艺。开发了一种高温密闭装置,通过提高蒸汽压的方法实现了350℃质子交换。波导折射率分布测试采用了棱镜薄膜耦合m线技术结合统计迭代法拟合的方法,晶相分析采用了红外吸收光谱技术。实验结果表明,掺入1.1%硬脂酸锂质量比例的硬脂酸作为缓冲质子源,经350℃/6h高温质子交换,可以形成α相铌酸锂光波导,稀释度为1.3%时,同样的温度/时间条件下,可以获得632.8nm单模α相铌酸锂光波导。  相似文献   

2.
退火质子交换LiNbO3光波导的工艺研究   总被引:7,自引:1,他引:6  
夏翔  袁一方 《光学仪器》2002,24(2):27-31
介绍了质子交换 Li Nb O3 光波导的制作工艺及光学特性测试 ,制作单模光波导的工艺条件及退火工艺。  相似文献   

3.
尽管可以采用光折变技术制备硫化砷条波导,但工艺参数控制复杂,且传输损耗较大。为了解决这一问题,提出了一种用于光阻断效应的新型B270-As2S8复合光波导结构。该设计根据光波导模式耦合的基本原理,借助波束传播法(BPM)仿真软件,主要通过对离子交换波导交换时间和As2S8薄膜厚度的匹配设计,实现了632.8nm波段导波模场分布集中在As2S8薄膜中传输,并始终维持单模特性。这个特点为有效实现光阻断效应提供了条件,非常具有实用价值。  相似文献   

4.
开发了一种新的自动调芯方法,在光纤-波导-光纤的自动对接中导入了遗传算法原理。数值仿真表明该方法达到了小于0.0001dB的插入损耗。完成了调芯系统样机,单模光纤-单模波导-单模光纤的自动对接实验显示,在1310nm和1550nm波长上,光纤-波导端面耦合损耗平均值分别为0.134dB和0.109dB,标准误差分别为0.009dB和0.012dB,调芯时间累计不超过8m in。  相似文献   

5.
离子交换单模条波导的折射率分布控制与制备   总被引:2,自引:2,他引:0  
为了控制离子交换条波导的折射率分布,提出并实施了离子交换等效扩散系数和表面折射率增量的实验确定方法,导出了离子交换条波导制备过程涉及的两维扩散方程的一般解,拟合推定了离子交换条波导的折射率分布。利用等效折射率法给出了单模波导条件,设计了相应的工艺参数,在0.1%AgNO_3—99.9%NaNO_3混合熔融盐中实验制备了单模条波导,模场分布测试结果显示了良好的单模特性。  相似文献   

6.
用氨水中和氟铌酸和氟氧铌酸制备的氢氧化铌表面强烈吸附氨,红外光谱分析在1400cm-1处有NH4+的v4(F4)简正振动模式特征峰。热重分析以及在不同温度下热处理的红外光谱分析结果表明,在500℃左右才能将NH3彻底从氢氧化铌表面脱除。因此,用氨中和方法制备氢氧化铌的正确化学表达式为NbOx(OH)y(NH4)x。在室温下用不同浓度的无机酸水溶液处理氢氧化铌后的红外光谱分析结果进一步证实了上述结论。用HNO3水溶液处理氢氧化铌可将NH4+交换下来,得到的氢氧化铌样品在300℃左右失重结束;用H2SO4水溶液处理氢氧化铌也可将NH4+交换下来,但SO42-在其表面发生了微弱的吸附作用,用稀H3PO4水溶液只能将部分NH4+交换下来,但同时PO34-在其表面发生了强烈的吸附作用。  相似文献   

7.
周霞  陈抱雪 《光学仪器》2012,34(3):87-90
为了制备As2S8波导,提出一种兼顾导波和光子作用的复合波导结构,叙述了B270-As2S8复合平面光波导的制备工艺。实验制备了复合平面光波导,采用双棱镜耦合的方法激励复合平面波导的导模,实现导模在波导中的传输,并且在复合平面波导上实现光阻断效应。结果表明该复合平面波导具有良好的传输特性,可应用于制备光开关等波导器件,具有一定的应用潜力。  相似文献   

8.
刘瑾  陈抱雪  杨海马 《光学精密工程》2011,19(10):2342-2348
设计并制备了离子交换单模条波导,用于激发等离子体表面波.研究了波导设计过程中相关参数的确定方法、条波导制备过程涉及的二维扩散问题,折射率分布以及等离子体表面波的激发等.基于Ag+-Na+离子交换技术在德国B270光学玻璃上制备出渐变型平面波导,采用余误差函数拟合其折射率分布,得到了一定工艺参数下的光波导扩散系数Deff...  相似文献   

9.
质子交换Z切LiNbO3光波导电光效应的研究   总被引:1,自引:1,他引:0  
电光效应是LiNbO3光波导的重要特性。但质子交换对LiNbO3光波导的电光系数γ33有较大的损失,当经过一定时间的退火处时后,其值得到一定程度的恢复。采用相位检测法,测量电光系数γ33值。分别对质子交换和退火后的LiNbO3光波导进行测试。并用对测试结果进行了分析,得出了合理的结论。  相似文献   

10.
张威  陈抱雪 《光学仪器》2017,39(4):66-69
设计了一种新的光路结构,用于提高LiNbO_3波导相位调制器的偏振消光比。光路特点是,在质子交换波导3dB功分器的输入端同基构造了Ti-LiNbO_3波导模式分离定向耦合的结构以实现TE导模与TM模分离,Y分支波导位置下沉以避免前向TM辐射模的窜扰。效果表现为,与保偏光纤端耦合寄生的TM辐射模得到了有效抑制,寄生的TM导模被定向疏散。1 550nm波长的BPM仿真运行表明,设计光路的偏振消光比达到87dB以上。  相似文献   

11.
An engineering system may consist of several different types of components,belonging to such physical"domains"as mechanical,electrical,fluid,and thermal.It is t...  相似文献   

12.
The intersection of Quantum Technologies and Robotics Autonomy is explored in the present paper.The two areas are brought together in establishing an interdisci...  相似文献   

13.
黑棣  郑美茹 《机电工程》2016,(11):1315-1321
针对具有进油孔的有限长滑动轴承油膜力求解问题,采用变分原理和分离变量法,求得了有限长滑动轴承油膜压力分布的近似解析表达式。将油膜压力分布的近似解析表达式在油膜存在区域上进行积分,即得到了油膜力。将提出的计算有限长滑动轴承油膜力方法与无限长轴承模型、有限元方法的计算结果进行了比较,发现了提出的方法与有限元方法的计算结果很接近。最后,研究了进油孔位置和进油压力对油膜存在区域、油膜力等的影响,研究结果表明进油孔位置和进油压力对油膜存在区域和油膜力有较大的影响。  相似文献   

14.
The strength of composite plate with different hole-shapes is always one of the most important but complicated issues in the application of the composite material. The holes will lead to mutations and discontinuity to the structure. So the hole-edge stress concentration is always a serious phenomenon. And the phenomenon makes the structure strength decrease very quickly to form dangerous weak points. Most partial damage begins from these weak points. According to the complex variable functions theory, the accurate boundary condition of composite plate with different hole-shapes is founded by conformal mapping method to settle the boundary condition problem of complex hole-shapes. Composite plate with commonly hole-shapes in engineering is studied by several complex variable stress fimction. The boundary integral equations are founded based on exact boundary conditions. Then the exact hole-edge stress analytic solution of composite plate with rectangle holes and wing manholes is resolved. Both of offset axis loadings and its influences on the stress concentration coefficient of the hole-edge are discussed. And comparisons of different loads along various offset axis on the hole-edge stress distribution of orthotropic plate with rectangle hole or wing manhole are made. It can be concluded that hole-edge with continuous variable curvatures might help to decrease the stress concentration coefficient; and smaller angle of outer load and fiber can decrease the stress peak value.  相似文献   

15.
The use of hand gestures can be the most intuitive human-machine interaction medium.The early approaches for hand gesture recognition used device-based methods....  相似文献   

16.
The fraction defective of semi-finished products is predicted to optimize the process of relay production lines, by which production quality and productivity ar...  相似文献   

17.
马立新  王宏宇 《机电工程》2015,32(1):118-122
针对传统的电力系统多目标粒子群优化算法采用权重系数法将多目标转化为单目标,从而忽视了各目标函数间的竞争关系这一问题,提出将非支配解提取法运用到电力系统多目标无功优化中,并设定了一套提取规则,以电力系统中的有功网损、电压偏差和电压稳定裕度为目标,使目标在充分竞争的情况下得出Pareto最优解,利用IEEE-14节点系统对多目标非支配解提取法的电力系统无功优化进行了仿真测试。研究结果表明,该算法一次运行可以得出多组非支配解,既有偏向单个目标的解也有兼顾所有目标的解,克服了权重系数法的盲目性和单一性,可使电力决策者根据实际问题选择最优解,具有较好的灵活性与多样性。  相似文献   

18.
针对实际电网存在着大量的三绕组变压器,但国际上一些著名商业软件,如BPA仿真软件、Matpower这一权威潮流计算开源软件,均只提供双绕组变压器模型,限制了其在具有三绕组变压器的电力系统中的应用的问题,潮流计算是自主开发的电力系统各种应用软件的核心模块,因此依托国际权威开源程序进行二次开发,是一种较好的选择。对Matpower要求的数据格式进行了归纳,对变压器的一般的等值电路及带理想变压器的等值电路和带标幺值的等值电路进行了分析研究,提出了三绕组变压器转换为双绕组等效模型的建模方法,使得原先只适应双绕组变压器的潮流计算软件可以适用于三绕组变压器电网的潮流计算;最后以Matpower软件为例进行了案例计算,并用PSASP仿真软件进行对比验证。研究结果证明,所提出的建模方法是有效的。  相似文献   

19.
A computer simulation model for the contact between longitudinally-oriented rough surfaces has been formulated. This model closely duplicates the actual surf ace contact deformation behavior by taking into account the elastic interactions between the asperities. There were no assumptions made about the shapes, or any deformation behavior of the asperities, except for their obeying the laws of elasticity. The plastic deformations on the high asperity peaks were taken into account by setting a ceiling on their contact pressures at the material hardness value. The simulations used real surface profiles which were digitized from unworn circumferentially ground steel surfaces. Each pair of these profiles was mathematically combined to form an equivalent rough profile pressing against an infinitely rigid flat and having the appropriately adjusted elastic modulus. A total of 28 different pairs of profiles were used in the simulations. Each contacting pair was subjected to 30 different load levels and the local contact pressures and deformations were calculated. The contact simulations yielded some important mathematical relationships between parameters, such as the real area of contact, average gap, and average asperity load through statistical curve fitting. Two analytical functions were generated to relate the average load to average gap and the real area of contact to load.  相似文献   

20.
A graph as the new engineering method for estimate the safety of bulging deformation of coke tower is proposed. Through stresses analysis of circumferential weld of coke tower and comparing the stresses produced by pressure with heat stress of steady state, residual stress, bending stress produced by both itself weight and wind loads, it showed that the stresses produced by pressure on the angle distortion are the main factor of equivalent stress of the combined stress. After comparing four kinds of stress controlling conditions, the relation to stress with depth of angular distortion, grade of curvature of angular distortion and half of region of angular distortion has been inferred. Graph of deformation allowable value of coke tower for different condition by angular distortion and half of region of angular distortion has been plotted. The five steps for its engineering use have been explained. The lighter the grade of curvature is, the larger of bulge allowance, may be, and the bigger of depth of angular distortion may pose too. For the coke tower with a popular structure of Dg 5 400 mm×28 mm, the result by graph is nearly more than the result of two formulas formed by other research, the error is less than 7.0%. But, the graph can be easily applied to different size of angular distortion.  相似文献   

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