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971.
A novel transflective liquid crystal display architecture and its system driving schemes are proposed. In the reflective mode, the ambient light is used to readout the displayed images. While in the transmissive mode, a color-sequential light emitting diode backlight is used to eliminate the color filters. Under such device configuration, several advantages such as increased brightness and maximized color saturation for both transmissive and reflective modes can be achieved 相似文献
972.
High-Performance Optical 3R Regeneration for Scalable Fiber Transmission System Applications 总被引:1,自引:0,他引:1
Zuqing Zhu Funabashi M. Zhong Pan Paraschis L. Harris D.L. Yoo S.J.B. 《Lightwave Technology, Journal of》2007,25(2):504-511
This paper proposes and demonstrates optical 3R regeneration techniques for high-performance and scalable 10-Gb/s transmission systems. The 3R structures rely on monolithically integrated all-active semiconductor optical amplifier-based Mach-Zehnder interferometers (SOA-MZIs) for signal reshaping and optical narrowband filtering using a Fabry-Peacuterot filter (FPF) for all-optical clock recovery. The experimental results indicate very stable operation and superior cascadability of the proposed optical 3R structure, allowing error-free and low-penalty 10-Gb/s [pseudorandom bit sequence (PRBS) 223-1 ] return-to-zero (RZ) transmission through a record distance of 1 250 000 km using 10 000 optical 3R stages. Clock-enhancement techniques using a SOA-MZI are then proposed to accommodate the clock performance degradations that arise from dispersion uncompensated transmission. Leveraging such clock-enhancement techniques, we experimentally demonstrate error-free 125 000-km RZ dispersion uncompensated transmission at 10 Gb/s (PRBS 223-1) using 1000 stages of optical 3R regenerators spaced by 125-km large-effective-area fiber spans. To evaluate the proposed optical 3R structures in a relatively realistic environment and to investigate the tradeoff between the cascadability and the spacing of the optical 3R, a fiber recirculation loop is set up with 264- and 462-km deployed fiber. The field-trial experiment achieves error-free 10-Gb/s RZ transmission using PRBS 223-1 through 264 000-km deployed fiber across 1000 stages of optical 3R regenerators spaced by 264-km spans 相似文献
973.
为了克服传统的通信电源效率测量方法在实际操作中的困难,提出了一种基于增量负载扰动和最小二乘拟合的通信电源效率测量方法。对于工作在"效率—输出负载电流"曲线中段的通信电源,对其施加增量负载扰动,并运用最小二乘拟合去除测量中奇异点对结果的影响,最终得到通信电源的效率。本文列出了运用该方法测得的实验结果,并讨论了实验结果的相对误差。通过该方法也可以对通信电源的欠载或过载状态进行定性的判断。最后本文提出了该方法在通信电源规模生产的自动化测试中的应用。因此该方法是一种实用的新型通信电源效率测量方法。 相似文献
974.
采用热注入法制备了Cu2ZnSnS4(CZTS)纳米颗粒,并形成高分散、稳定的"墨水",采用滴注方法形成CZTS前驱体薄膜。利用X射线衍射(XRD)、拉曼光谱(Raman)、透射电子显微镜(TEM)和紫外-可见光谱(UV-VIS)对CZTS纳米颗粒的晶体结构、表面形貌和带隙进行了表征。Raman数据显示合成的纳米颗粒为纯的CZTS,不存在ZnS和Cu2SnS3等杂相。傅里叶红外光谱(FTIR)和UV-VIS表明合成的CZTS纳米颗粒表面被油胺(OLA)包覆,并且其带隙为1.52 eV。对CZTS前驱体薄膜在硫化氢气氛和固态硒气氛中退火处理,得到铜锌锡硫硒(CZTSSe)薄膜。结果表明,经硫化氢处理后薄膜表面平整但CZTS晶粒并没长大,而经过固态硒处理后得到了结晶质量较好的CZTSSe薄膜。 相似文献
975.
976.
This letter deals with blind identification of nonlinear discrete Hammerstein system under the input signal that is cyclostationary. The first-order moment of the specific input as well as the inverse nonlinear mapping of the Hammerstein model are combined to establish a relationship between the system output and the system parameters, which implies an approach to identifying the system blindly. Simulation results demonstrate the effectiveness of this approach to blind identification of a class of nonlinear systems. 相似文献
977.
郎格罕氏细胞(Lange Hans cell.LC)是从骨髓中的前体细胞衍化而来的树突状细胞,主要位于表皮基层上方.有摄取抗原、处理抗原和传递抗原的功能,起着免疫系统外围前哨的作用.LC的功能可受各种理化因子的影响,是否也会受到激光照射的影响?鲜见文献报道.本文探讨低功率CO2激光照射后,表皮LC的数目形态和分布的情况. 相似文献
978.
Guomei Zhu Geng-Sheng Kuo 《Lightwave Technology, Journal of》2008,26(5):560-568
Due to the emergence of high-capacity wavelength-division multiplexing transmission systems, new optical cross-connect (OXC) architectures that make a large number of fiber/wavelength counts to switch the signal in the optical domain are needed. Optical microelectromechanical system (MEMS) switches are regarded as the most promising optical switch technology to achieve such functionalities. In this paper, we propose a novel integrated multistage two-dimensional (2-D) MEMS optical switch design with Spanke-Benes architecture and compare it with the conventional crossbar architecture, the L-switching architecture, and Shuffle-Benes architecture. Our proposed architecture is very suitable for building large-port-count 2-D MEMS switches and achieves much better performance in terms of beam divergence loss, longest optical path, mirror radius, substrate size, port-to-port repeatability, and power consumption than the other three architectures. Furthermore, compared with the 2-D conventional crossbar switch commercially available now, the proposed architecture can save 50% mirrors, shorten 87.5% longest optical path, minify 65% mirror radius, and shrink 90% substrate size. 相似文献
979.
An asymmetrically-loaded interdigital coupled line is proposed for design of wideband microstrip bandpass filters with good out-of- band performance. This interdigital coupled line with three fingers is formed by stretching one of two outer arms with one two-stage open-ended stub. Its characteristics are analysed in terms of admittance matrix to exhibit simultaneous emergence of extra transmission zeros in lower and upper stopbands. A wideband filter with two half-wavelength resonators is then designed and fabricated. Measured results show low-loss wide passband in the range 2.95-5.15 GHz and highly attenuated stopbands at DC to 2.2 GHz and 6.6-10.0 GHz, respectively. 相似文献
980.