Laser beam shaping in an apodizer with a rectangular serrated aperture

Profile transformation of a uniform monochromatic beam with a flat wavefront after the propagation through an apodizer comprising a square serrated aperture and a spatial filter is theoretically considered at the apodizer exit and behind it. Main differences from the case of the circular apo-dizer geometry are shown. Roles of the square serrated aperture angles, the phase in Fresnel diffraction, the shape of the aperture serrations and serration height-to-period ratio are analyzed.