Figure 2

Charges of vector beams generated by superposition of scalar vortices.
The calculated OAM charge for the vector beams generated with equation (8) of and
at different zenith angle in spherical coordinate (the Poincaré sphere). Green dots of OAM charges are calculated with our formula, which are corresponding to cases shown in Fig. 1(a–d), respectively. Solid lines are calculated by mode expansion method according to equation (8).