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运用非傍轴光束传输的矢量矩理论,对任意线偏振高斯光束的非傍轴传输进行了系统的研究,给出了定量计算偏振对束腰、横向远场发散角和光束传输因子贡献的解析通式. 并对高度非傍轴和傍轴两种极端情形,简化了相应的计算式. 在高斯光源线度趋向于零的极限情形下,两个横向的最大发散角均为90°,与偏振态无关. 在高度非傍轴情形下,可以通过所给出的解析通式设计高斯光源的半宽度与激射光波长之比值以及线偏振态来达到所期望的光束传输特性. 对于傍轴情形,不同偏振对束腰和横向远场发散角稍有影响,但这种影响一般可以忽略不计;而光束传输因子却始终保持不变,与偏振态无关. 若介于这两种极端情形之间,则可以根据高斯光源的半宽度之值和所期望的计算精度,确定解析式中级数的项数进而确定任意线偏振高斯光束的非傍轴传输特性.
关键词:
高斯光束
非傍轴传输
偏振
二阶矩 相似文献
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运用非傍轴光束传输的矢量矩理论,对非傍轴矢量高斯光束的传输特性进行了系统的研究.结果表明,基于二阶矩定义的横向光束宽度在光束传播过程中满足简单的双曲线变化规律,并且给出了光束传输因子的解析表达式.就高度非傍轴情形,进一步给出了简洁的计算公式,在高斯光源线度趋向零的极限情形下,横向的最大发散角为90°.同时,还推广到了傍轴情形,得到了与原有傍轴公式稍有区别的结果,而且光束传输因子始终保持略大于1最后,对非傍轴矢量高斯光束和非傍轴标量高斯光束的传输进行了比较,结果显示对于线度在两个波长范围之内的高斯光源发散
关键词:
矢量高斯光束
光束传输
非傍轴
二阶矩 相似文献
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矢量可控空心光束的非傍轴传输 总被引:1,自引:1,他引:0
提出了矢量可控空心光束概念,可控空心光束可以很好地描写中心光强不完全为零的圆对称窄心光束,具有可用多个参最米控制中央暗斑尺寸、形式简单易于分析、其传输变换特性更接近于实际等特点.利用矢量瑞利-索末菲衍射积分公式,导出了矢量可控空心光束的非傍轴传输解析公式,从所得结果可退化得到傍轴近似结果.利用导出的公式计算分析了矢量可控空心光束在自由空间的非傍轴传输特性,并与傍轴结果进行了比较分析.结果表明矢量可控空心光束在近场很好地保持其空心光场分布特性;参量f和传输距离决定了矢量可控空心光束的非傍轴特性. 相似文献
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非傍轴截断平顶光束的质量因子 总被引:1,自引:0,他引:1
使用功率密度的二阶矩方法和Li提出的平顶光束模型,推导出了非傍轴截断平顶光束的束腰宽度、远场发散角和光束质量因子的解析表达式。计算结果表明:非傍轴截断平顶光束的质量因子不仅与截断参数、光束阶数有关,而且与初始束腰宽度和波长之比有关;当截断参数趋近于0时,远场发散角趋于渐近值63.435°;对于光束阶数为1和截断参数趋于无穷大的特例,计算结果分别退化为非傍轴截断高斯光束和非傍轴无截断平顶光束的结果;功率密度的二阶矩方法可用于截断光束,并克服了光束质量因子的发散困难。 相似文献
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By using the second-order moment of the power density, the beam width, far-field divergence angle and M2 factor of nonparaxial truncated flattened Gaussian (FG) beams are derived analytically. It is shown that the M2 factor of nonparaxial truncated FG beams depends not only on the truncation parameter δ and beam order N, but also on the initial waist-width to wavelength ratio w0/λ. The far-field divergence angle approaches an asymptotic value of θmax=63.435° when the truncation parameter δ → 0. For the special cases of N = 0 and δ → ∞ our results reduce to those of nonparaxial truncated Gaussian beams and nonparaxial untruncated FG beams, respectively. 相似文献
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Scalar Approximation of Super-Gaussian Beams 总被引:1,自引:0,他引:1
CHEN Huilong CAO Qing FAN Dianyuan 《Chinese Journal of Lasers》1998,7(6):515-519
1IntroductionThemodesofacavitywithsuperGausianreflectivityareknownassuperGausianbeams,theydescribeawholefamilyoffielddistri... 相似文献
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The propagation characteristics of TM polarized Gaussian beam, which is the rigorous solution of an eigenfunction problem for a confocal resonator, have been investigated using the nonparaxial vectorial moment theory of light beam propagation. The analytical expressions of the beam propagation factors are given by means of Fourier transform. Both the transversal second-order moment beam widths follow a simple hyperbolic variational law. For nonparaxial case, however, beam has different propagating features in the two transversal directions. As to paraxial case, its propagation approximately reduces to that of scalar Gaussian beam TEM00 mode. 相似文献
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Propagation and polarization properties of hollow Gaussian beams in uniaxial crystals 总被引:1,自引:0,他引:1
Based on the paraxial vectorial theory of beams propagating in uniaxially anisotropic media, we have derived the analytical propagation equations of hollow Gaussian beams (HGBs) in uniaxial crystals, and given the typical numerical example to illustrate our analytical results. Due to the anisotropy crystals, the ordinary and extraordinary beams originated by incident HGBs propagate with different diffraction lengths, thus the linear polarization state and axial symmetry of incident HGBs do not remain during propagating in crystals. 相似文献