Abstract: A parallel plate beam forming lens is formed form at least three parallel plates, and includes a plurality of beam port waveguides, each coupled to a beam port divider with a step increase in waveguide height. The beam port divider comprises a first divider having two outputs separated by a resistive septum, each of which is coupled to a second divider having two outputs separated by a resistive septum, with all of the second divider outputs coupled to a lens region through beam port apertures. On the opposite end from the beam port waveguides is a plurality of array port waveguides forming a transformer, thereafter to a section of waveguide, and thereafter to an array port divider including a resistive septum coupled to the lens region and a step decrease in waveguide height. Also positioned at the extents of the beam port apertures and the array port apertures are a plurality of dummy ports.