中红外2 μm Tm∶YLF激光热效应分析

基于2 μm Tm∶YLF激光器的实际工作条件建立了各向异性激光晶体的稳态热模型,通过解析法得到了Tm晶体内温度场分布的解析表达式;模拟并分析了泵浦功率、光斑半径、晶体端面尺寸对Tm晶体内温度场分布的影响。最终得到了在不同条件下晶体内部温度分布,结果表明：掺杂浓度的增加加剧了晶体的温升,增加了晶体热畸变不均匀性,产生更明显的热效应;而晶体长度的适度增加降低了晶体的温升,缓解了晶体热畸变不均匀性,削弱了晶体的热效应。所得结论可以为LD抽运Tm∶YLF激光器的腔型及散热系统设计提供理论支持。     

光参量放大拼接晶体加工误差补偿系统设计

晶体拼接技术能够解决光参量啁啾脉冲放大(OPCPA)过程中非线性晶体口径受限问题,从而有效地提高放大器的输出能力。晶体加工误差补偿是晶体拼接要解决的核心问题之一。对拼接晶体加工误差对光束质量的影响进行了分析,设计了拼接晶体加工误差补偿方案,设计并加工完成拼接晶体加工误差补偿能动反射镜。通过实验验证了拼接晶体加工误差补偿方案的可行性和稳定性,同时证明了该系统满足晶体拼接要求。     

助熔剂法生长GaPO4晶体

采用助熔剂法生长了GaPO4晶体。热重-差热(TG-DSC)分析得到晶体的熔点为1 070℃,采用紫外-可见分光光度计测量了晶体的室温紫外-近红外透过谱,采用红外光谱分析仪测量了晶体的红外透过谱。结果表明,GaPO4晶体透光波段很宽,采用助熔剂法生长晶体有效地抑制了晶体中OH-基团的产生。     

光子晶体及其在光通信中的应用研究

介绍了光子晶体的概念,分析了光子晶体在光通信中的主要应用,讨论了光子晶体光纤的光传输性质以及由光子晶体构造的光通信器件,指出了光子晶体对未来光通信技术发展的重要意义。     

模式识别的光子晶体光纤传感器误差校正研究

为了克服当前光子晶体光纤传感器误差校正方法存在的不足,提出了模式识别的光子晶体光纤传感器误差校正方法。首先分析光子晶体光纤传感器误差产生原因,然后采集光子晶体光纤传感器误差历史数据,引入模式识别技术对光子晶体光纤传感器误差进行学习,并对光子晶体光纤传感器误差进行校正,最后并与其它方法进行了光子晶体光纤传感器误差校正仿真实验。结果表明,本文方法提升了光子晶体光纤传感器误差校正准确性,能够刻画光子晶体光纤传感器误差变化趋势,光子晶体光纤传感器误差校正效果明显好于对比方法,验证了本文方法的优势。     

电光晶体用于快速变焦的设计

在利用晶体的电光效应实现快速变焦时,需要合理地设计电光晶体及电极结构。基于晶体电光效应的基本原理,提出了其设计的基本原则和思路,并通过对一次电光晶体(铌酸锂晶体)和二次电光晶体(钽铌酸钾晶体)内部非均匀电场及其总附加光程的模拟和比较,获得了优化的电光晶体及电极设计结果。在此基础上,开展了电光晶体用于快速变焦设计的性能分析,并讨论了电光晶体长度、外加电压等参数对总附加光程的影响。结果表明:电光晶体的附加光程调制的曲率半径随控制电压增大而减小,在加载电压不变的情况下随晶体厚度的增大而增大。因此,在实际应用中,需要对晶体厚度和加载电压综合进行考虑,以获得最佳的变焦效果。     

Gd∶PbWO_4晶体的生长及其闪烁性能研究

在 Ｐｂ Ｗ Ｏ４ 晶体中掺进 Ｇｄ２ Ｏ３,采用 Ｃｚｏｃｈｒｏｌｓｋｉ法生长 Ｇｄ∶ Ｐｂ Ｗ Ｏ４ 晶体。测试晶体的透射光谱,激光发射光谱,抗辐照损伤能力和发光效率。 Ｇｄ∶ Ｐｂ Ｗ Ｏ４ 晶体的透过率,抗辐照损伤能力和发光效率皆优于纯 Ｐｂ Ｗ Ｏ４ 晶体。 Ｇｄ∶ Ｐｂ Ｗ Ｏ４ 晶体的吸收边紫移,提高了透过率,从而提高了发光效率。 Ｇｄ３＋ 掺入 Ｐｂ Ｗ Ｏ４ 晶体中,抑制了 Ｐｂ３＋ 的存在,提高了晶体抗辐照损伤能力。 Ｇｄ∶ Ｐｂ Ｗ Ｏ４ 晶体是比 Ｐｂ Ｗ Ｏ４ 晶体性能更为优良的闪烁晶体。     

激光晶体的微观缺陷与宏观光学性质

激光晶体的微观结构与其宏观光学性质密切相关。晶体的宏观光学性质是其微观结构的表现。晶体的微观缺陷,直接影响晶体的物理和光学性质。本文用固体理论对常用的几种激光晶体的微观缺陷和宏观光学性质的关系进行了分析和论证,并与实验作了比较。一、晶体微观缺陷的宏观表现晶体的微观结构与其宏观性质密切相关。晶体的微观缺陷,直接影响晶体的物理和光学性质。例如,理想的Nd~(3 ):YAG激光晶体,是具有空间对称性的立方晶体,它的各向异性     

基于边界对流传热的LD端面抽运圆柱形晶体的热效应

通过对激光二极管(LD)端面抽运棒状Nd:YAG晶体的热效应进行理论分析,考虑晶体内部抽运光束分布及连续抽运过程中晶体周边与冷却液之间的对流传热,建立了更为合理的边界条件,得出更符合实际的晶体温度分布场,同时计算了晶体半径以及晶体散热面积对热效应的影响.研究结果表明,考虑边界对流传热后,计算的晶体中心温度升高,晶体边界温度也相应升高,相应的晶体热焦距稍有增加;减小晶体半径,晶体中心与表面的温度差均减小,热焦距增大,晶体热效应降低;增大晶体散热面积虽然降低晶体内部温度场,但由于端面抽运的特点导致晶体中心附近温度变化率增加,反而使热焦距减小,加剧了晶体热效应.     

用垂直布里奇曼法生长CdTe晶体

用垂直布里奇曼法生长了CdTe晶体,并检验了晶体的质量。发现,在最佳条件下,能获得缺陷密度较低和晶体完整性较高的晶体。     

Technology innovation and process integrations for sub-100nm gate patterning

This paper presents a brief overview of the Applied Centura(R)DPS(R)system,configured with silicon etch DPS Ⅱ chamber, with emphasis on discussing tuning capability for CD uniformity control. It also presents the studies of etch process chemistry and film integration impact for an overall successful gate patterning development. Discussions will focus on resolutions to key issues, such as CD uniformity, line-edge roughness, and multilayer film etching integration.     

White organic light-emitting devices based on fac tris（2- phenylpyridine） iridium sensitized 5,6,11,12-tetraphenylnap -hthacene

We have fabricated the white organic light-emitting devices （WOLEDs） based on 4,4＇ -bis（2,2 -diphenyl vinyl）-1,1＇ - biphenyl （DPVBi） and phosphorescence sensitized 5,6,11,12,-tetraphenylnaphthacene （rubrene）. The device structure is ITO/2T-NATA （20 nm）/NPBX （20 nm）/CBP： x%Ir（ppy）3：0.5% rubrene （8 nm）/NPBX （5 nm）/DPVBi （30 nm）/Alq（30 nm）/LiF（0.5 nm）/A1. In the devices, DPVBi acts as a blue light-emitting layer, the rubrene is sensitized by a phosphorescent material, fac tris （2-phenylpyridine） iridium [Ir（ppy）3], acts as a yellow light-emitting layer, and N,N＇ -bis- （1-naphthyl）- N,N＇ -diphenyl -1, 1＇ -biphenyl-4,4＇ -diamine （NPBX） acts as a hole transporting and exciton blocker layer, respectively. When the concentration of Ir （PPY）3 is 6wt%, the maximum luminance is 24960 cd/m^2 at an applied voltage of 15 V, and the maximum luminous efficiency is 5.17 cd/A at an applied voltage of 8 V.     

Complete approach to automatic identification and subpixel center location for ellipse feature

To meet the need of automatic image features extraction with high precision in visual inspection, a complete approach to automatic identification and sub-pixel center location for similar-ellipse feature is proposed. In the method, the feature area is identified automatically based on the edge attribute, and the sub-pixel center location is accomplished with the leastsquare algorithm. It shows that the method is valid, practical, and has high precision by experiment. Meanwhile this method can meet the need of instrumentation of visual inspection because of easy realization and without man-machine interaction.     

小角度扩展相关性近似算法分析

本论文提出一种在多天线MIMO信道相关性建模中小角度扩展近似理论算法,并应用于分析MIMO系统性能。分析中分别对三种不同角能量分布情况下的空间相关性研发快速近似计算法,并同时提出双模(Bi-Modal)角能量分布情况下的近似运算。通过分析这些新方法的近似效率,可以得到计算简单、复杂度低、而且符合实际的MIMO相关信道矩阵,对系统级的快速高效计算法的研究和系统级的评估以及误差分析具有重要的意义。     

A Versatile Mixed-Signal Pin Approach for Cost-Effective Test of Automotive ICs

Integrated circuits (ICs) intended for increasingly sophisticated automotive applications bring unique test demands. Advanced ICs for applications such as highly integrated automatic braking system (ABS) and airbag controllers combine high voltage digital channels, significant VI demands and precise timing capability. Along with continued missioncritical reliability concerns, the trend toward higher voltage operation and increased device integration requires specialized test capabilities able to extend across the wide operating ranges found in automotive applications. Among these capabilities, automotive test requirements increasingly dictate a need for a cost-effective versatile mixed-signal pin electronics with very high data rates reaching up to 50MHz with a voltage swing of-2 V to +28 V.     

Optical vibration and deviation measurement of rotating machine parts

It is of interest to get appropriate information about the dynamic behaviour of rotating machinery parts in service. This paper presents an approach of optical vibration and deviation measurement of such parts. Essential of this method is an image derotator combined with a high speed camera or a laser doppler vibrometer （LDV）.     

社长序言（英文）

正Happy New Year!As we step into a new year,we take a look back at the key feature topics covered in China Communications over the past 12 months and set out our expecta-     

Call for Papers

正Introduction Jointly sponsored by the China Institute of Communications(CIC)and the IEEE Communications Society(IEEE ComSoc)since the year 2013,China Communications,currently,is aiming to gradually realise the transition from journal to magazine content and style.     

INTEGRATION OF OPTICAL AND WIRELESS NETWORKS

正For a long time,optical and wireless systems/net-works are developed in separate communities witha few attempts for in-depth convergence.In fact,it prom-ises many advantages to combine the optical and wire-less technologies in the levels of systems and networks.Recently,both academia and industry have made manyefforts to enter a new phase of development to take op-tical and wireless systems as fully integrated networks.To provide high bandwidth and reliable service for bothfixed and mobile users,a well-designed network must     

Call for Papers—Feature Topic,Vol.12,No.3,2015

正Smart Grid Communications The electric power industry is undergoing profound changes as the industry aims to capture the promise of a smart grid for a sustainable energy future.Enabled by the advanced sensing devices such as Phasor Measurement Units(PMUs),increasingly powerful