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 apodizer 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.