Fig. 3: Spectral response of broadband unidirectional visible imagers.

a Output image of PCC values as a function of the illumination wavelength for both the forward and backward directions. b Diffraction efficiency as a function of the illumination wavelength for both the forward and backward directions. The dashed curves represent the performance of the two-layer unidirectional imager design shown in Fig. 1b, while the solid curves represent the performance of the three-layer unidirectional imager design shown in Fig. S1. The gray areas mark the illumination wavelengths used during the training of the diffractive optical processors