Focusing properties of vector Bessel-Gauss beam with multiple-annular phase wavefront

Focusing properties of vector Bessel-Gauss (BG) beam with multiple-annular phase wavefront is investigated by vector diffraction theory in this article. The multiple-annular phase wavefront modulation is given by a function of radial direction angle and m. It was found that the focal properties can be altered considerably by the multiple-annular phase wavefront modulation parameter m, including the shape, size and focus shifts are variable with the change of parameters. There is an remarkable phenomenon that both the focal region and the gradient force distribution are symmetrical about the horizontal axis. In a word, the properties of the vector Bessel-Gauss (BG) beam with multiple-annular phase wavefront are considerably altered by the multiple-annular phase wavefront parameters, especially influenced the shape of focal region, and the quantity of intensity peak, but having no influence on the symmetry.