共查询到20条相似文献,搜索用时 15 毫秒
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SC-type single-mode optical fiber connectors 总被引:1,自引:0,他引:1
SC-type single-mode optical fiber connectors specifically developed for subscriber loop networks are discussed. The properties and design of precision zirconia ceramic ferrules which have been found to be ideal for high-performance, low-cost single-mode optical fiber connectors are described. A design approach featuring a plastic-molded rectangular connector housing using a push-pull coupling mechanism which has also been found to be suitable for durable, compact, and low-cost connectors is presented. SC connectors used with 10/125 single-mode fibers exhibit insertion loss of 0.06 dB and return loss of 38.6 dB, with no degradation during and after mechanical and environmental tests. To realize higher packaging density, duplex-ferrule connectors, quadruple-ferrule connectors and optical attenuators have also been developed on the basis of the SC connector design 相似文献
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An approximate analytical model is developed for calculating the out-of-plane coupling efficiency between an elliptical Gaussian beam from a laser diode and an angled single-mode fiber. The simulation results obtained from the model indicate that when a laser diode has no tilt the coupling efficiency varies with relative rotation angle at a period of π rather than remains constant, and the period changes from π toward 2π as the tilt angle of laser diode increases. A proof-of-principle experiment is performed to demonstrate the validity of the model as the elliptical factor becomes large. Potential applications by employing the model are discussed 相似文献
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Mossadegh R. Sanghera J.S. Schaafsma D. Cole B.J. Nguyen V.Q. Miklos R.E. Aggarwal I.D. 《Lightwave Technology, Journal of》1998,16(2):214-217
Long lengths (>150 m) of single-mode chalcogenide optical fiber were fabricated by a double crucible technique. Single-mode transmission through 10 m of continuous fiber was demonstrated using an F-center laser at 2.7 μm. The optical loss of this fiber was measured by a standard cutback technique using an FTIR spectrometer and also using an F-center laser, A minimum loss of less than 1 dB/m was obtained 相似文献
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Random coupling theory of single-mode optical fibers 总被引:1,自引:0,他引:1
Tian Feng Wu Yizun Ye Peida 《Lightwave Technology, Journal of》1990,8(8):1235-1242
A random coupling theory is developed for analyzing the propagation characteristics of the polarization state of light in single-mode optical fibers (including conventional and polarization maintaining fibers) under random disturbances. The basic idea is that the disturbances that a fiber suffers in practice continuously change with time and space, so time-varying coupling will occur along the fiber between two linearly polarized modes HE11 that may propagate in the fiber. A coupled-mode equation of single-mode fibers under random disturbances is derived and solved rigorously with few assumptions. A random coupled-mode equation is derived considering time and space variation. Analytic solutions are obtained and used for analyzing the effect of random birefringence, polarization dispersion, polarization fluctuation, and evolution of the degree of polarization in single-mode fibers and for characterizing fiber properties 相似文献
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A single-mode optical fiber model is proposed with discrete mode-coupling centers having random coupling coefficients at regular intervals. The degree of polarization in a single-mode fiber with random-mode coupling does not approach zero with increasing fiber length. Numerical results show that the ensemble average of the degree of polarization approaches a nonzero value the magnitude of which depends on the coupling intensity, the light source spectrum, the fiber birefringence, and the spatial frequency of coupling centers, The theoretical and numerical results clarify the limitation of the perturbation iteration method for long optical fibers. 相似文献
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由于多模光纤的纤芯直径远大于单模光纤的纤芯直径,且多模先纤的数值孔径也大于单模光纤的数值孔径,因此多单模转换效率极低.为了提高多模光纤到单模光纤的耦合效率,采用自聚焦透镜对从多模光纤出射的光束进行汇聚,使其半径大小尽量与单模光纤的芯径大小相匹配,然后再利用球透镜来减小被汇聚过的光束的发散角,在不考虑各种连接损耗的前提下,通过ZEMAX来求解多模光纤到单模先纤的耦合效率.采用这种新型组合透镜耦合的方法可以极大提高多单模耦合的耦合效率,其最高耦合效率可达到38.7%.因此,这种组合透镜法是可行的. 相似文献
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A precise method of measuring core center dispersion in single-mode fiber arrays is presented. This approach dispenses with the use of high-precision linear translation stages and is based on a direct comparison of the fiber core center position to a simple lithographically patterned template. Combining image recognition and efficient processing algorithm, the fiber-core center positions of fiber arrays can be determined with precision of order of 0.1 /spl mu/m, in both longitudinal and transversal directions. Complementary information about the position of fibers within v-grooves as well as bending of multifiber arrays can be also obtained. 相似文献
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Polarization fluctuation characteristics of single-mode optical fiber output are examined theoretically and experimentally. A fiber model for studying these characteristics from the perspective of probability on the Poinare sphere is proposed. The relationship of the degree of polarization fluctuation to time and fiber length is shown theoretically. Measurements of submarine and underground cables and long-haul fibers up to 270 km in length generally support the proposed model 相似文献
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Raman amplifier model in single-mode optical fiber 总被引:2,自引:0,他引:2
I. Mandelbaum M. Bolshtyansky 《Photonics Technology Letters, IEEE》2003,15(12):1704-1706
Equations to describe the process of Raman amplification in single-mode optical fiber and Stokes and anti-Stokes spontaneous emission generation with conservation of photon number are derived from first principles. The numerical simulation of Stokes and anti-Stokes spontaneous emission is in good agreement with experimental results. The importance of the sometimes-omitted anti-Stokes spontaneous emission terms in wavelength-division-multiplexed situations for optical signal-to-noise ratio is demonstrated by the simulation of light propagation through transmission fiber with and without Raman amplification. 相似文献
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近年来由于单模光纤研究的极大成功,促进了单模光纤通信系统和单模光纤应用技术的迅速发展。单模光纤的实际损耗已降到接近理论值,因此为进一步改善单模光纤传输系统的信噪比,提高激 相似文献
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Snowbell M. Strasman N. Fischer B. Cronin-Golomb M. 《Lightwave Technology, Journal of》1995,13(1):55-61
We present and demonstrate a method for efficient coupling of many beams into a single-mode fiber. Using the phase conjugating property for mutually incoherent beams of the double phase conjugate mirror (DPCM), we achieved coupling for a full 6×6 matrix of beams into a single-mode fiber. In principle, this number of input channels can be increased manyfold beyond the 36 used in our experiment. Of the phase conjugate generated by the DPCM in the direction of the fiber, over 97% (Fresnel corrected) entered the fiber, thus giving a highly accurate coupling. The DPCM transmission efficiency itself was measured at 40% (Fresnel corrected), thus giving an overall coupling efficiency of 39%. By optimizing the DPCM parameters, a significantly higher overall coupling could be achieved. An additional advantage of this method is that the DPCM will reconfigure if there are small changes in the system, thus making the system very robust. This multichannel coupling method can be of importance in the coupling of the output beams of a vertical cavity surface emitting laser (VCSEL) into a single-mode fiber where each channel may carry independently modulated information. This technique can be further generalized to a bidirectional multisingle-mode fiber interconnection system, of which a basic 3×2 system is demonstrated 相似文献
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空间光到光纤的耦合是自由空间光通信的关键技 术,针对光纤纤芯直径很小,给耦合 带来很大困难这一问题,文章先分析了空间光到单光纤的耦合模型,然后提出了采用锥形光 纤阵列提高耦合效率的接收方法,之后,在实验室试制了锥形光纤阵列样品,并在微振动环 境下采用两种方法测量接收光功率,第一种方法是采用一个大靶面雪崩光电二极管(APD) 同时接收九根光纤光功率,第二种方法是采用熔融拉锥型光分路器将9根光纤中的光合并进 入一根光纤,然后用光功率计进行测量,测量结果表明,采用第一种方法比第二种方法得到 的光功率稍高,这是因为熔融拉锥后的光纤会有能量泄露。从总体上看,两种接收方法均说 明锥形光纤阵列样品达到了预期的接收效果。 相似文献
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M. Wada K. Yoshino M. Yamada J. Temmyo 《Photonics Technology Letters, IEEE》1991,3(11):953-955
An investigation of epitaxial-layer structures has yielded narrow ridge waveguide structure lasers capable of coupling high optical power into single-mode fiber (SMF). An optical power of well over 60 mW in SMF was obtained for a 2- mu m-wide ridge waveguide laser with a guided separate-confinement-heterostructure (SCH) epitaxial structure. Calculated results indicate that the stringent limit imposed on 0.98- mu m wavelength detuning is relaxed for such high optical power coupled into a SMF. The 0.98- mu m strained-quantum-well lasers thus show considerable promise as a practical low-noise pumping source for Er-doped optical-fiber amplifiers.<> 相似文献
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单模光纤非线性系数n2/Aeff的测量方法 总被引:2,自引:0,他引:2
通信距离的延长和WDM通道数的增加使光纤非线性效应日益显著,如何准确地测量非线性系数的大小成了人们关注的问题,文章介绍了几种非线性系数的测量方法,并对它们的优缺点进行了较全面的分析和比较。 相似文献
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An effective method for coupling optical signals from single-mode fibers to thin-film waveguides is proposed. The authors show that this method provides high coupling efficiency for connecting fibers of different core diameters to thin-film waveguides of different film thicknesses or refractive indexes. The authors summarize the theoretical treatment of the coupler. Examples of couplers designed for SiO2 -based materials as well as iron garnets are presented. Fabrication of the proposed coupler and its experimental results are described 相似文献
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A method for obtaining permanent low-loss couping between arrys of single-mode fiber and Ti:LiNbO3 waveguides is described. The technique, based on the use of silicon chip V-grooves, simplifies the coupling problem by simultaneously aligning the entire array and by providing a large surface area for a higher integrity adhesive bond. Atlambda = 1.3 mu m, we measure an average 1.9-dB coupling loss (exclusive of propagation loss) for the assembled array. The average excess loss due to the fiber array is 0.8 dB. We present an analysis of the effect of various types of array misalignment on coupling efficiency. Angular alignment and array periodicity are found to be critical. If the fiber and waveguide periodicities are matched exactly, the fibers need only be placed withinpm 1.3mu m of their optimum position to maintain coupling efficiencies greater than 90 percent. 相似文献