TITLE:
Focal shift of radially polarized bessel-modulated gaussian beam by phase shifting
AUTHORS:
Xiu-Min Gao, Ming-Yu Gao, Song Hu, Han-Ming Guo, Jian Wang, Song-Lin Zhuang
KEYWORDS:
Focal Shift; Bessel-Modulated Gaussian Beam; Vector Diffraction Theory
JOURNAL NAME:
Natural Science,
Vol.1 No.3,
December
15,
2009
ABSTRACT: Focal shift of radially polarized Bessel-modu- lated Gaussian (QBG) beam by phase shifting is investigated theoretically by vector diffraction theory. The phase shifting distribution is the function of the radial coordinate. Calculation results show that intensity distribution in focal region can be altered considerably by the topo- logical charge of QBG beam and the phase pa-rameter that indicates the vary degree of the phase shifting along radial coordinate. Topolo- gical charge induces the focal shift in trans-verse direction, while phase parameter leads to the focal shift along optical axis of the focusing system. More interesting, the focal shift may be incontinuous in certain case.