Upper right: simulated image at λ = 560 nm of the nulled PSF, which considers the measured phase unaccuracy on the transmissive chessboard. Upper left: the measured PSF obtained by scanning the SMFO. One pixel corresponds to one step of displacement of the SMFO of 200 nm. Middle panel: same as upper panel but at the wavelength of 650 nm. Lower panel: same as upper panel but in a broad wavelength range of about 450–840 nm.