(a) Maximum THz electric field amplitude, normalised to the mean value, as the polarization angle is varied over a 360° range by changing the relative bias voltages between horizontal and vertical pixels. The inset shows the bias voltage applied for each target polarization angle. (b) Comparison of the experimentally measured orientation angle to the target angle at each step. The dashed line represents an exact match between the two. (c) Polar representation of the orientation angle and amplitude of the THz pulses at each step. (d) Ellipticities of the generated THz radiation at each orientation angle, at 1 THz (blue) and averaged from 0.3-5.0 THz (red). The shaded areas represent the variation over the 360° rotation.