The diffraction propagation properties of double-half inverse Gaussian hollow beams

• We propose a new style hollow beams–double-half inverse Gaussian hollow beams.
• We simulate the distribution of the optical field with different initial spot size and different propagating distance.
• We show a laser beam with flat-top.

In the paper, double-half inverse Gaussian hollow beams, which are a new type of hollow beams, have been proposed. In the paraxial approximation, the propagation model of double-half inverse Gaussian hollow beams in free space is deduced by utilizing the Collins formula. The distribution of the optical field is simulated with different initial spot sizes (ω0=1 mm and 5 mm) and different propagating distances (z=10 mm, 6×102 mm, 1.5×103 mm, 1×104 mm and z=10 mm, 1.5×104 mm, 3×104 mm and 10×104 mm). And the simulated results demonstrate that the Airy pattern is derived after propagating some distance. Meanwhile, the focusing property appears visibly and the energy is redistributed intricately. In the research, the focusing distance could be controlled by transforming the initial spot size and the intensity inequality is also shown.