摘要
基于近轴光束传输理论,对多色径向偏振光束(PRPB)传输中的光强及光谱分别进行了研究。结果表明:在近场区,光源的谱宽增加会使得PRPB的光斑尺寸有微小增大;在远场区,光源的谱宽增加会使得PRPB的光斑尺寸有微小减小。在光谱特性方面,观测平面上总存在一个临界位置,其内部点光谱表现为蓝移,外部点表现为红移;无论在近场还是远场,光源谱宽的增加都会使得临界位置远离光束中心。在光源谱宽确定的情况下,远场区观测点的光谱谱移量要明显高于近场区;从PRPB与多色线偏振高斯光束的对比中发现,在相同传输距离处,多色径向偏振光束的临界位置的半径明显大于多色线偏振高斯光束。
Based on paraxial approximation of beam propagation, intensity and spectra of polychromatic radially polarized beam （PRPB） are investigated during propagation. It is found that, in near field, the increase of the original spectral width introduces a little increase of the beam width of PRPB; however in the far field, the increase of the original spectral width can cause a little decrease of the beam width of PRPB. As to spectral property, there always exists a critical position on observing plane, inside of the critical position, the observed spectrum is blue-shifted, and outside of the critrcal position, the observed spectrum is red-shifted. The increase of original Spectral width will push the critical position away from the beam center wherever in the near field or far field. For the case of certain original spectral width, the observed spectral shift width in far field is bigger than that in the near field. Besides, while comparing the PRPB with the polychromatic linearly polarized Gaussian beam, it is found that at the same propagation distance, the radius of the critical position of PRPB is obviously bigger than that of the polychromatic linearly polarized Gaussion beam.
出处
《中国激光》
EI
CAS
CSCD
北大核心
2015年第4期304-310,共7页
Chinese Journal of Lasers
基金
国家自然科学基金(61307001
61178015)
福建省自然科学基金(2013J05094
2014J05007)
关键词
物理光学
多色径向偏振光束
光强
光谱
临界位置
physical optics
polychromatic radially polarized beam
intensity
spectra
critical position
