In order to study the generation of the vector beams by using the polarization modulation of the spatial variant wave-plate, the Jones vectors and Jones matrix are used to further discuss the process, in which an arbitrary Laguerre-Gaussian beam can be transformed into vector beam. Based on the mathematical mode, the far-field intensity distributions of the generated vector beams have been simulated by numerical method. The simulated results show that, the line-polarized and circularly polarized beams with basic mode can be converted to vector beams by using spatial variant half-wavelength plate and quarter wavelength plate respectively, and the dark core of the output beam increases with an increase of the order of the spatial variant wave-plate. The effects of the spatial variant wave-plate on the helical beams can be equivalent to the superposition of two mutually orthogonal circularly polarized helical beams. The polarization test of the orbital angular momentum confirms the practicability of this method.
