Doughnut beam generation using acousto-optic cell

Spatial characteristics of diffracted beams produced by an acousto-optic cell from an incident Gaussian beam are studied theoretically. The complex amplitude distribution of a diffracted beam is described using Collins integral and ABCD matrix formalism. Obtained results show that the output intensity profile differs from the incident Gaussian beam shape and takes a form of doughnut beam for a specific values of the acoustic pressure inside the acousto-optic cell and the truncature parameter, defined as the ratio of the acoustic wavelength and the laser beam width.