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光纤准直器高回波损耗的理论分析与研究 总被引:5,自引:0,他引:5
在高斯光束传输理论的基础上,利用矩阵光学 原理和高斯光束耦合理论得出了斜面耦合自聚焦透镜型光纤准直器的回波损耗的数学表达式。分析了发迹光纤准直器的参数而引起回波损耗变化的原因。实验结果与理论分析比较吻合。 相似文献
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提出了一种新型光学接收天线的设计和制作方法,利用干涉和衍射原理在全息材料上制成具有聚集光束和滤除环境光双重功能的全息反射镜.通过耦合波理论与k矢量闭合法分析了这种光学接收天线的角度选择性、光谱选择性以及任意点的衍射效率,模拟结果表明:全息反射镜在不同点的视场角和光谱带宽分别为0.8°~13.4°和4.4nm~7.4nm,并且整体衍射效率在95.3%以上.与由聚光镜和滤波片组合成的传统光学接收天线相比,全息反射镜体积小、重量轻、成本低、能作为光学接收天线用于室内可见光通信系统中. 相似文献
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原子反射镜是人们从事原子光学实验研究的重要器件之一.本文将简单综述采用冷原子磁、光操控技术发展起来的诸如消逝波原子反射镜、半高斯光束原子反射镜、周期性磁化的磁带反射镜、周期性排列的永久磁铁反射镜和载流导线磁反射镜等各种原子反射镜的基本原理、实验方案及其最新进展,并就原子反射镜在原子光学实验中的应用作一简单介绍. 相似文献
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提出了一种用来描述空心光束的新理论模型——空心高斯光束模型,通过控制光束参数可以方便地调制空心光束黑斑的大小.导出了空心高斯光束经傍轴光学系统的解析传输变换公式.利用导出的公式计算分析了空心高斯光束在自由空间的传输特性.在实验上利用矩阵本征值方法设计了能输出空心高斯光束的光学谐振腔,对实验上得到的空心高斯光束进行了传输特性的研究.结果表明,理论和实验相吻合.该空心高斯光束产生的光势阱为控制冷原子提供了一条新途径.
关键词:
空心高斯光束
光学谐振腔
传输特性 相似文献
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As a complementary scheme to a coupling-hole type laser, a walk-off ring coupling type laser is proposed to extract a donut shaped beam by shrinking the diameter of one of the stable resonator mirrors. This was successfully applied to a conventional slow axial-flow CO laser. First, finding the intensity distribution close to the Gaussian profile by using a partially transparent mirror in a hemispherical configuration for coupling, we obtain the relationship between the mirror radius and the effective transmittance. Then, using several mirrors with a diameter smaller than the Gaussian profile above instead of the partially transparent mirror, the output power with the donut shape was optimized to yield the maximum power, together with theoretical treatments. This resulted in an optimum mirror diameter of 4.2 mm, which corresponds to the optimum transmittance of 5-6% for the CO laser having the gain parameter G≅0.34, the inherent loss ā ≅ 0.07, and the measure of partial homogeneity m¯ =; 0.5. This value is exactly the same as that of the coupling-hole mirror. Some application feasibilities are also discussed. 相似文献
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Huiyun Wu Haotong Ma Xiaojun Xu Jinbao Chen Yijun Zhao 《Optical and Quantum Electronics》2013,45(1):1-9
Improving power coupling efficiency of beam uplink propagation in a relay mirror system is under extensive research in recent years. A typical model of the relay mirror system is established and theory of beam shaping used to improve power coupling efficiency of the relay mirror system is analyzed in detail. A reduced-scale experimental relay mirror system is founded, which has the same Fresnel number as uplink propagation in the relay mirror system with 1.0 m-caliber transmitter and 30?km propagation distance. Phase distribution of the source is optimized by using the stochastic parallel gradient descent algorithm. The experimental results showed that power coupling efficiency of uplink propagation in the reduced-scale relay mirror system was improved from 72.67 to 87.88 % by beam shaping and the bucket power proportion in 5 pixels at the target was improved from 45.49 to 52.78 %. 相似文献
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为了降低高斯光束与谐振腔耦合过程中失调量和失配量对基于无源谐振腔测量技术精度的影响, 采用高斯光束变换规律、模式耦合有关理论以及光束传播坐标变换等相关理论, 就失调量和失配量对基模耦合效率的影响分别进行分析和模拟, 并据此给出了一般情况下两个参考量同时存在时基模耦合效率的表达式. 分析表明: 失配量的存在主要影响激光器与谐振腔的耦合效率, 而对高阶模式的激发影响较小, 因此对谐振腔的衰减线型影响较小; 失调量的存在对谐振腔高阶模式的激发起主要作用, 给测量带来严重误差. 该结论为利用腔出射光信号来确定误调参量值的实验方案提供了依据. 因此, 在考虑光源光谱线宽的情况下, 就光源光谱线宽的特性提出两种装调校准方案: 基于法布里-珀罗干涉仪法和基于多维象限探测器探测谐振腔出射光的调节回路, 这将为分析基于无源谐振腔的相关技术测量误差来源以及实现测量系统的高精度装调提供理论指导. 相似文献
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N. Umamageswari M. Udhayakumar K. B. Rajesh Z. Jaroszewicz 《Optical and Quantum Electronics》2017,49(5):191
Focusing properties of the cylindrical vector axisymmetric Bessel-modulated Gaussian beam with quadratic radial phase dependence (QBG beam) in high numerical aperture parabolic mirror system is investigated theoretically by vector diffraction theory. Results show that intensity distribution in focal region can be altered considerably by beam parameter μ and polarization angle. The tightly focused cylindrically polarized axial symmetric Bessel-modulated Gaussian beams by a high numerical aperture parabolic mirror have possible applications in particle acceleration, optical trapping and manipulating, single molecule imaging and high resolution imaging microscopy. 相似文献
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Huiyun Wu Haotong Ma Xiaojun Xu Jinbao Chen Wuming Wu Yijun Zhao 《Optics & Laser Technology》2011,43(3):488-490
The model of two-Cassegrain-telescopes system used in a relay mirror system is established and the theory of beam shaping for the relay mirror system as well as optimization control algorithm is analyzed. Experiment of the reduced-scale relay mirror system with 3 mm-caliber transmitter and 0.27 m propagation distance was done. The results show that power coupling efficiency of the system without beam shaping is 72.67% and power coupling efficiency of the system with beam shaping is 84.14%. 相似文献
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Based on scalar diffraction theory, propagation properties of beam generated by Gaussian mirror resonator were investigated. Explicit expressions for the field distribution of the beam that propagate through a paraxial optical ABCD system were derived and numerical examples were given to illustrate our analytical results. 相似文献
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A general formula for evaluating Gaussian beam coupling characteristics on a MEMS mirror array was developed, with consideration of parameters such as beam size, mirror width and mirror gap. Based on the formula, the influence of each parameter on the spectral response was simulated for MEMS mirror array employed in a wavelength selective switch and a tunable optical filter. The simulation results are helpful for the design of MEMS mirror array in optical devices. 相似文献
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N. G. C. Astrath F. B. G. Astrath J. Shen J. Zhou C. E. Gu L. C. Malacarne P. R. B. Pedreira A. C. Bento M. L. Baesso 《Applied physics. B, Lasers and optics》2009,94(3):473-481
A complete theoretical model is presented for the thermal mirror technique under top-hat laser excitation. Considering the
attenuation of the top-hat excitation laser intensity along the thickness of a sample due to its optical absorption coefficient,
we calculate the laser-induced temperature and surface deformation profiles. A simplified theoretical model for a high absorption
sample is also developed. The center intensity of a probe beam reflected from the thermal mirror at a detector plane is derived.
Numerical simulation shows that the thermal mirror under the top-hat laser excitation is as sensitive as that under Gaussian
laser excitation. With top-hat laser excitation, the experimental results of thermo-physical properties of opaque samples
are found to be well consistent with literature values, validating the theory. 相似文献
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D. V. Vinogradov 《International Journal of Infrared and Millimeter Waves》1995,16(11):1945-1963
The surface of an inclined mirror, which converts Gaussian beams with simple astigmatism hase been found within the quasi-optical approximation. The beam reflected from the found mirror was examined. Power losses of the reflected beam, when the beam is incident on a selective system, which transmits a Gaussian beam of one polarization only have been found. 相似文献