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161.
1 Introduction Alongperiodfibergrating (LPFG)isanovelpassivefiberelementarisinginrecentyears[1] .SeveralapplicationsofLPFGhavebeenfound ,suchas gain profileflattenedfilter,band rejectionfilter,andtemperature ,strainornewchemicalsensors[2 ,3] .ItcanbeUV writtenor… 相似文献
162.
一种基于光纤萨尼亚克环的新型传感结构 总被引:1,自引:0,他引:1
提出了一种实现全光纤多扰动测量的基于光纤萨尼亚克环的新型传感结构。该传感结构采用新型的双萨尼亚克环结构并用波分复用技术代替了传统的双光源结构,减小了系统损耗,实现了对多扰动的位置的测量。分析了传感原理,推导了数学模型,表明测量误差与解调电路的频率响应有关,并进行了单频和多频扰动的实验研究,实验证明了理论分析的正确性。 相似文献
163.
Using Hefei Synchrotron radiation as X-ray source and photoresist PMMA as recording medium, soft X-ray contact microscopic imaging experiment on hydrated leaf epidermal cells of a kind of dicotyledon is performed and its latent image is read out by a light microscope. Several main factors degrading the resolution of the image are discussed in detail. 相似文献
164.
Optical multistability of a Fabry-Perot semiconductor laser is analyzed when multi-optical inputs detuned from the cavity-resonant wavelength of a semiconductor laser are injected. Many split branches are shown to be produced in the optical output versus optical input characteristics for different detuned optical inputs. It is also shown that optical outputs can be switched in any one of the optical input wavelengths by optical input pulses, based on the optical output versus input characteristics with multi-split branches. 相似文献
165.
In this paper, the chromatic dispersion and chromatic dispersion slope of two kinds of triple-clad single-mode fibers with a depressed index inner cladding named WI- and WII-type were examined. A feasible approach to calculate chromatic dispersion and higher-order dispersion was established successfully, and the influences made by the optical parameters and geometric parameters on the chromatic dispersion coefficient and its slope were analyzed in detail. The calculated results show that the optical parameter R2, which symbolizes the third cladding effect, has a strong impact on the chromatic dispersion coefficient and the chromatic dispersion slope, and the degrees of such impact are closely related to the other parameters. 相似文献
166.
167.
1.IntroductionInthepastfe\\'ycarsltllcil1tcnsity-momentsmethodandtheM2factorhavebeenre-vea1edtobeveryuscfulrotlcscribethepropagationlawandthebeamqualityofastaticlightbeam[l~Jj.Rccent1y,1ncji:1sctal.generalizedtheintensitymomentsmethodfortheSCLQ(speetral1y`"el1-centcrcdandlocallyquasi-monochromatic)pulsedlightboms[5j.Itisapparentthatthosercsu]tsubtainedinreferenceL5]areon1yvalidfortheso-calledquasi-monochromaticlightbeamsandarenotvalidforgeneralpolychromaticpulsedlightbeams,esPeciallyaredono… 相似文献
168.
169.
非晶态HoP5O14的蓝绿波段上转换发光的分析 总被引:2,自引:0,他引:2
本文报道了脉冲DCM染料激光导致的非晶态HoP5O14的兰绿波段的上转换发光现象,从实验和理论上对其上转换发光的现象,机理和能道行了测量,分析和计算;结果表明对^5F3和S2能级,其上转换发光主要由离间能量传递机理导致;对5G4和(5G3G)5能级,则步进双光子吸收和离子间能量传递共同参与导致了它们的上转换发光。 相似文献
170.
A major obstacle in realizing fast packet switching in all-optical networks is the large tuning delays of tunable optical devices. This article proposes a multiaccess scheme for all-optical local area networks that employs both wavelength and code concurrency. In this scheme, several users share a wavelength channel through code multiplexing. The delay performance of hybrid wavelength/code division multiaccess is obtained under a simple, suboptimal access protocol based on cyclic search. Due to the reduction in the number of wavelength channels without an associated reduction in transmission concurrency, hybrid multiaccess is robust against tuning delays. At a given network throughput, the hybrid scheme achieves considerably lower delays than that of Wavelength Division Multiple Access even with a small amount of code concurrency. Conversely, the hybrid network can support a higher load when there is a maximum allowable value for the average packet delay. 相似文献