Abstract: A polarizing screen for altering a polarization state of a radio frequency waveform radiated from a parallel plate waveguide (PPW) wherein the waveform has a centre frequency and a bandwidth, the polarizing screen comprising a plurality of developable sheets arranged stacked in parallel to each other in direction of a local normal vector of a first sheet at respective inter-sheet spacings, each sheet comprising an electrically conductive pattern forming a one-dimensional periodic structure of unit-cells in an extension direction, wherein the periodic structure is associated with a height measured orthogonally to the extension direction and orthogonally to the local normal vector of the shat, where each cell comprises an aperture configured to transmit the radio frequency waveform at a predetermined polarization state, wherein the height is determined in dependence of the centre frequency and/or the bandwidth of the radio frequency waveform such that the pre-determined polarization state is provided as well as