高级检索

Ince-Gaussian矢量光场束腰位置对紧聚焦特性影响的研究

Research on the effect of waist position changing of Ince-Gaussian vectorial beam on tightly focusing characteristics

  • 摘要: 为了获得Ince-Gasussian矢量光场束腰位置对紧聚焦特性的影响规律,采用正交偏振的奇偶模式叠加理论和Richards-Wolf矢量衍射积分理论,对不同束腰位置的Ince-Gaussian矢量光场紧聚焦特性进行了研究。结果表明,在高数值孔径聚焦条件下,入射Ince-Gaussian矢量场的束腰距离透镜位置zi在一定瑞利长度zR范围内(zi < 0.5zR)改变时,其聚焦场的横向场结构即光强与偏振态分布,依然可以保持稳定;通过聚焦场相位结构分析,给出了在束腰距离透镜位置zi超过一定瑞利长度zR范围(zi>0.5zR)时,影响横向场结构不稳定的原因;聚焦场纵向偏振分量作为聚焦场的一个自由度,被证明可以用来构建更加丰富的矢量结构光场。此研究结果对复杂结构矢量光场在光学微操控与光信息存储方面的研究有重要参考价值。

     

    Abstract: In order to research the influence of the beam waist position on the tightly focusing of the Ince-Gaussian vectorial beam, the superposition theory of orthogonally polarized even and odd modes and the Richards-Wolf vector diffraction integral theory were utilized in this study and the tightly focusing feature of the Ince-Gaussian vectorial beam at the different waist position was analyzed. The results show that under the condition of high numerical aperture focusing, the transverse field structure of the focusing field possessing distribution of light intensity and polarization state can still remain stable when the distance zi between the beam waist position of the Ince-Gaussian vectorial field and the lens changes within a certain Rayleigh length zR (zi < 0.5zR). By analyzing the phase structure of the focusing field, the reason of the instability of the transverse field structure is given when the distance zi between the beam waist position and the lens exceeds a certain Rayleigh length zR (zi>0.5zR). At the same time, the longitudinal polarization component of the focusing field, as a degree of freedom of the focusing field, can be used to construct a more abundant vector structured light field. The results can provide great value for the research of complex structure vector optical field in optical micromanipulation and optical information storage.

     

/

返回文章
返回