Generation of Bessel Beams at mm- and submm-Wave Bands Using Binary Optical Elements

We apply binary optical elements (BOE's), designed by using a genetic algorithm (GA) for global optimization and a two-dimension finite-difference time-domain (2-D FDTD) method for rigorous electromagnetic computation, to generate Bessel beams at mm and submm-wave bands. Numerical results demonstrate that the designed BOE's can not only successfully produce arbitrary order Bessel beams, but also have higher diffraction efficiencies when compared with amplitude holograms.