Abstract

Ring-shaped focus, such as focused vortex beam, has played an important role in microfabrication and optical tweezers. The shape and diameter of ring-shaped focus can be easily adjusted by the topological charge of vortex. However, the flow energy is also related to the topological, making the individual control of diameter and flow energy of vortex beam is impossible. Meanwhile, the shape of focus vortex beam remains to the hollow ring. Expanding the shape of focus structural light broadens the applications of vortex beam in the field of microfabrication.

Here, we proposed a ring-shaped focus with controllable gaps by multiplexing the vortex beam and annular beam. The multiplexed beam has the several advantages, such as the diameter and flow energy of the focal point can be individually controlled, is not affected by the zero-order beam, and the gap size and position are controllable.